Table of contents
  1. Story
  2. Spotfire Dashboard
  3. Research Notes
  4. Slides
    1. Title Slide
      1. Slide 1 NASA QUDT Handbook
    2. Introductions
      1. Slide 2 Roadmap
      2. Slide 3 Introductions
      3. Slide 4 What is QUDT?
      4. Slide 5 Motivations for "Model Driven" QUDT 1
      5. Slide 6 Motivations for "Model Driven" QUDT 2
      6. Slide 7 Motivations for "Model Driven" QUDT 3
      7. Slide 8 Motivations for "Model Driven" QUDT 4
      8. Slide 9 Motivations for "Model Driven" QUDT 5
      9. Slide 10 QUDT: "Real World" Benefits 1
      10. Slide 11 QUDT: "Real World" Benefits 2
    3. Quantities, Units and Dimensions 101
      1. Slide 12 Roadmap
      2. Slide 13 Kinds of Physical Quantities
      3. Slide 14 of Measure
      4. Slide 15 Dimensions and Dimensional Analysis
      5. Slide 16 Quantities Need a Standard Vocabularly
    4. NASA QUDT Handbook
      1. Slide 17 Roadmap
      2. Slide 18 NASA QUDT Handbook HDBK-1003R
      3. Slide 19 Formal Model: Quantities and Units in OWL
      4. Slide 20 What is an Ontology? 1
      5. Slide 21 What is an Ontology? 2
      6. Slide 22 Key Requirements: QUDT Ontologies
      7. Slide 23 Benefits of QUDT Ontologies
    5. NASA QUDT Handbook
      1. Slide 24 Roadmap
      2. Slide 25 NASA QUDT Handbook HDBK-1003R
      3. Slide 26 QUDT Scope
      4. Slide 27 QUDT: "Real World" Benefits
      5. Slide 28 Applicability
      6. Slide 29 NASA QUDT Handbook: Content
      7. Slide 30 NASA QUDT Handbook: Quantity Kind Domains
      8. Slide 31 NASA QUDT Handbook: Example Propulsion Quantity Kinds
      9. Slide 32 NASA QUDT Handbook: Example An ISO-80000 QuantityKind
      10. Slide 33 QUDT Name, Identifier and Usage Rules
      11. Slide 34 Example of a Rule
      12. Slide 35 Model-Driven Traceability
      13. Slide 36 QUDT Industry & Standards Alignment
      14. Slide 37 QUDT Models ISO-80000
    6. QUDT Ontology Models
      1. Slide 38 Roadmap
      2. Slide 39 Conceptual Model of QUDT
      3. Slide 40 Conceptual Model of QUDT (Notes)
      4. Slide 41 QUDT Information Architecture
      5. Slide 42 Ontology Example: Quantity Kinds and Units (1)
      6. Slide 43 Ontology Example: Quantity Kinds and Units (2)
    7. How the QUDT Handbook Was Produced
      1. Slide 44 Roadmap
      2. Slide 45 How the QUDT Handbook Was Produced
      3. Slide 46 Example of Semantic Markup
    8. Next Priorities
      1. Slide 47 Roadmap
      2. Slide 48 Next Priorities
      3. Slide 49 How To Find Out More
      4. Slide 50 Thank You
  5. QUDT
    1. Overview
      1. Status
      2. Goals
    2. QUDT Ontologies and Vocabularies
      1. Ontology Class Structure
        1. Quantities, Quantity Kinds, and Quantity Values
        2. Quantity Kinds
        3. Unit of Measure
        4. Quantity Value
        5. Numerical Quantity Value
        6. Quantity Symbol
        7. Systems of Quantities and Units
        8. Base and Derived Quantity Kinds
        9. Quantity Dimensions
        10. Dimensionless Quantities and Units
        11. Allowed Units
        12. Example Quantity Kind and Unit Systems
        13. The SI System
        14. The CGS System
        15. CGS Units for Electricity and Magnetism
          1. EMU Derived Units
          2. ESU Derived Units
      2. Glossary
      3. Acknowledgements
      4. References
  6. Instances
    1. Instances of qudt:AtomicPhysicsQuantityKind
      1. quantity:AtomicCharge: Atomic Charge
      2. quantity:GyromagneticRatio: Gyromagnetic Ratio
      3. quantity:LinearEnergyTransfer: Linear Energy Transfer
    2. Instances of qudt:BiologyQuantityKind
      1. quantity:HeartRate: Heart Rate
      2. quantity:MicrobialFormation: Microbial Formation
      3. quantity:RespiratoryRate: Respiratory Rate
      4. quantity:SerumOrPlasmaLevel: Serum or Plasma Level
    3. Instances of qudt:ChemistryQuantityKind
      1. quantity:AmountOfSubstance: Amount of Substance
      2. quantity:AmountOfSubstancePerUnitMass: Amount of Substance per Unit Mass
      3. quantity:AmountOfSubstancePerUnitVolume: Amount of Substance Per Unit Volume
      4. quantity:CatalyticActivity: Catalytic Activity
      5. quantity:Concentration: Concentration
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:EnergyAndWorkPerMassAmountOfSubstance: Energy and Work per Mass Amount of Substance
      8. quantity:InverseAmountOfSubstance: Inverse Amount of Substance
      9. quantity:LengthMolarEnergy: Length Molar Energy
      10. quantity:MassAmountOfSubstance: Mass Amount of Substance
      11. quantity:MassAmountOfSubstanceTemperature: Mass Amount of Substance Temperature
      12. quantity:MolarEnergy: Molar Energy
      13. quantity:MolarMass: Molar Mass
      14. quantity:MolarVolume: Molar Volume
      15. quantity:MoleFraction: Mole Fraction
      16. quantity:MolecularMass: Molecular Mass
      17. quantity:TemperatureAmountOfSubstance: Temperature Amount of Substance
      18. quantity:Turbidity: Turbidity
    4. Instances of qudt:CommunicationsQuantityKind
      1. quantity:RF-Power: RF-Power
      2. quantity:SignalDetectionThreshold: Signal Detection Threshold
      3. quantity:SignalStrength: Signal Strength
    5. Instances of qudt:ElectricityAndMagnetismQuantityKind
      1. quantity:AuxillaryMagneticField: Auxillary Magnetic Field
      2. quantity:Capacitance: Capacitance
      3. quantity:CubicElectricDipoleMomentPerSquareEnergy: Cubic Electric Dipole Moment per Square Energy
      4. quantity:ElectricCharge: Electric Charge
      5. quantity:ElectricChargeLineDensity: Electric Charge Line Density
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:ElectricChargePerArea: Electric Charge per Unit Area
      8. quantity:ElectricChargePerMass: Electric Charge per Mass
      9. quantity:ElectricChargeVolumeDensity: Electric Charge Volume Density
      10. quantity:ElectricConductivity: Electric Conductivity
      11. quantity:ElectricCurrent: Electric Current
      12. quantity:ElectricCurrentDensity: Electric Current Density
      13. quantity:ElectricCurrentPerAngle: Electric Current per Angle
      14. quantity:ElectricCurrentPerUnitEnergy: Electric Current per Unit Energy
      15. quantity:ElectricCurrentPerUnitLength: Electric Current per Unit Length
      16. quantity:ElectricDipoleMoment: Electric Dipole Moment
      17. quantity:ElectricDisplacementField: Electric Displacement Field
      18. quantity:ElectricField: Electric Field
      19. quantity:ElectricFlux: Electric Flux
      20. quantity:ElectricPotential: Electric Potential
      21. quantity:ElectricPower: Electric Power
      22. quantity:ElectricQuadrupoleMoment: Electric Quadrupole Moment
      23. quantity:ElectromotiveForce: Electromotive Force
      24. quantity:EnergyPerAreaElectricCharge: Energy per Area Electric Charge
      25. quantity:EnergyPerElectricCharge: Energy per Electric Charge
      26. quantity:EnergyPerSquareMagneticFluxDensity: Energy per Square Magnetic Flux Density
      27. quantity:ForcePerElectricCharge: Force per Electric Charge
      28. quantity:Inductance: Inductance
      29. quantity:InverseMagneticFlux: Inverse Magnetic Flux
      30. quantity:InversePermittivity: Inverse Permittivity
      31. quantity:LengthPerUnitElectricCurrent: Length per Unit Electric Current
      32. quantity:LengthPerUnitMagneticFlux: Length per Unit Magnetic Flux
      33. quantity:MagneticDipoleMoment: Magnetic Dipole Moment
      34. quantity:MagneticField: Magnetic Field
      35. quantity:MagneticFlux: Magnetic Flux
      36. quantity:MagneticFluxPerUnitLength: Magnetic Flux per Unit Length
      37. quantity:MagnetizationField: Magnetization Field
      38. quantity:MagnetomotiveForce: Magnetomotive Force
      39. quantity:MassPerElectricCharge: Mass per Electric Charge
      40. quantity:Permeability: Permeability
      41. quantity:Permittivity: Permittivity
      42. quantity:Polarizability: Polarizability
      43. quantity:PolarizationField: Polarization Field
      44. quantity:PowerPerElectricCharge: Power per Electric Charge
      45. quantity:QuarticElectricDipoleMomentPerCubicEnergy: Quartic Electric Dipole Moment per Cubic Energy
      46. quantity:Resistance: Resistance
    6. Instances of qudt:FinancialQuantityKind
      1. quantity:Asset: Asset
      2. quantity:Currency: Currency
    7. Instances of qudt:FluidMechanicsQuantityKind
      1. quantity:AtmosphericPressure: Atmospheric Pressure
      2. quantity:Circulation: Circulation
      3. quantity:DynamicPressure: Dynamic Pressure
      4. quantity:DynamicViscosity: Dynamic Viscosity
      5. quantity:KinematicViscosity: Kinematic Viscosity
      6. quantity:MolecularViscosity: Molecular Viscosity
      7. quantity:Pressure: Pressure
      8. quantity:ReynoldsNumber: Reynolds Number
      9. quantity:StaticPressure: Static Pressure
      10. quantity:TotalPressure: Total Pressure
      11. quantity:Viscosity: Viscosity
      12. quantity:Vorticity: Vorticity
    8. Instances of qudt:InformationQuantityKind
      1. quantity:Capacity: Capacity
      2. quantity:DataRate: Data Rate
      3. quantity:InformationEntropy: Information Entropy
      4. quantity:VideoFrameRate: Video Frame Rate
    9. Instances of qudt:MechanicsQuantityKind
      1. quantity:AngularMomentum: Angular Momentum
      2. quantity:AreaPerTime: Area per Time
      3. quantity:Density: Density
      4. quantity:EnergyAndWork: Energy and Work
      5. quantity:EnergyDensity: Energy Density
      6. quantity:EnergyInternal: Internal Energy
      7. quantity:EnergyKinetic: Kinetic Energy
      8. quantity:EnergyPerArea: Energy per Area
      9. quantity:Force: Force
      10. quantity:ForceMagnitude: Force Magnitude
      11. quantity:ForcePerArea: Force Per Area
      12. quantity:ForcePerAreaTime: Force Per Area Time
      13. quantity:ForcePerLength: Force per Unit Length
      14. quantity:Friction: Friction
      15. quantity:GravitationalAttraction: Gravitational Attraction
      16. quantity:InverseEnergy: Inverse Energy
      17. quantity:InverseSquareEnergy: Inverse Square Energy
      18. quantity:KineticEnergy: Kinetic Energy
      19. quantity:LengthByForce: Length Force
      20. quantity:LengthEnergy: Length Energy
      21. quantity:LengthMass: Length Mass
      22. quantity:LinearMomentum: Linear Momentum
      23. quantity:Mass: Mass
      24. quantity:MassPerArea: Mass per Area
      25. quantity:MassPerAreaTime: Mass per Area Time
      26. quantity:MassPerLength: Mass per Length
      27. quantity:MassPerTime: Mass per Time
      28. quantity:MolarAngularMomentum: Molar Angular Momentum
      29. quantity:MomentOfInertia: Moment of Inertia
      30. quantity:Momentum: Momentum
      31. quantity:PolarMomentOfInertia: Polar moment of inertia
      32. quantity:PotentialEnergy: Potential Energy
      33. quantity:Power: Power
      34. quantity:PowerArea: Power Area
      35. quantity:PowerAreaPerSolidAngle: Power Area per Solid Angle
      36. quantity:PowerPerArea: Power per Area
      37. quantity:PowerPerAreaAngle: Power per Area Angle
      38. quantity:SpecificEnergy: Specific Energy
      39. quantity:SpecificImpulseByMass: Specific Impulse by Mass
      40. quantity:SpecificImpulseByWeight: Specific Impulse by Weight
      41. quantity:SpecificVolume: Specific Volume
      42. quantity:SquareEnergy: Square Energy
      43. quantity:StandardGravitationalParameter: Standard Gravitational Parameter
      44. quantity:Thrust: Thrust
      45. quantity:ThrustToMassRatio: Thrust to Mass Ratio
      46. quantity:Torque: Torque
      47. quantity:Weight: Weight
    10. Instances of qudt:PhotometryQuantityKind
      1. quantity:Illuminance: Illuminance
      2. quantity:Luminance: Luminance
      3. quantity:LuminousEfficacy: Luminous Efficacy
      4. quantity:LuminousEmmitance: Luminous Emmitance
      5. quantity:LuminousEnergy: Luminous Energy
      6. quantity:LuminousFlux: Luminous Flux
      7. quantity:LuminousFluxPerArea: Luminous Flux per Area
      8. quantity:LuminousIntensity: Luminous Intensity
    11. Instances of qudt:QuantityKind
      1. quantity:AbsoluteHumidity: Absolute Humidity
      2. quantity:Dimensionless: Dimensionless
      3. quantity:DimensionlessRatio: Dimensionless Ratio
      4. quantity:Gain: Gain
    12. Instances of qudt:QuantumMechanicsQuantityKind
      1. quantity:Action: Action
      2. quantity:Activity: Activity
    13. Instances of qudt:RadiologyQuantityKind
      1. quantity:AbsorbedDose: Absorbed Dose
      2. quantity:AbsorbedDoseRate: Absorbed Dose Rate
      3. quantity:DoseEquivalent: Dose Equivalent
      4. quantity:Exposure: Exposure
    14. Instances of qudt:RadiometryQuantityKind
      1. quantity:Irradiance: Irradiance
      2. quantity:Radiance: Radiance
      3. quantity:RadiantEmmitance: Radiant Emmitance
      4. quantity:RadiantEnergy: Radiant Energy
      5. quantity:RadiantFlux: Radiant Flux
      6. quantity:RadiantIntensity: Radiant Intensity
      7. quantity:Radiosity: Radiosity
      8. quantity:FirstMomentOfArea: First Moment of Area
      9. quantity:SecondMomentOfArea: Second Moment of Area
      10. quantity:Strain: Strain
      11. quantity:StrainEnergyDensity: Strain Energy Density
      12. quantity:Stress: Stress
      13. quantity:Tension: Tension
    15. Instances of qudt:SpaceAndTimeQuantityKind
      1. quantity:Acceleration: Acceleration
      2. quantity:Angle: Angle
      3. quantity:AngularAcceleration: Angular Acceleration
      4. quantity:AngularFrequency: Angular Frequency
      5. quantity:AngularVelocity: Angular Velocity
      6. quantity:Area: Area
      7. quantity:AreaAngle: Area Angle
      8. quantity:AreaTime: Area Time
      9. quantity:Curvature: Curvature
      10. quantity:DryVolume: Dry Volume
      11. quantity:Frequency: Frequency
      12. quantity:InverseLength: Inverse Length
      13. quantity:InverseVolume: Inverse Volume
      14. quantity:Length: Length
      15. quantity:LinearAcceleration: Linear Acceleration
      16. quantity:LinearVelocity: Linear Velocity
      17. quantity:LiquidVolume: Liquid Volume
      18. quantity:MachNumber: Mach Number
      19. quantity:NumberDensity: Number Density
      20. quantity:PlaneAngle: Plane Angle
      21. quantity:SolidAngle: Solid Angle
      22. quantity:Speed: Speed
      23. quantity:StochasticProcess: Stochastic Process
      24. quantity:Time: Time
      25. quantity:TimeSquared: Time Squared
      26. quantity:Velocity: Velocity
      27. quantity:Volume: Volume
      28. quantity:VolumePerUnitTime: Volume per Unit Time
    16. Instances of qudt:SystemOfQuantities
      1. quantity:SystemOfQuantities_CGS: CGS System of Quantities
      2. quantity:SystemOfQuantities_CGS-EMU: CGS-EMU System of Quantities
      3. quantity:SystemOfQuantities_CGS-ESU: CGS-ESU System of Quantities
      4. quantity:SystemOfQuantities_CGS-Gauss: CGS-Gauss System of Quantities
      5. quantity:SystemOfQuantities_Planck: Planck System of Quantities
      6. quantity:SystemOfQuantities_SI: International System of Quantities
      7. quantity:SystemOfQuantities_USCustomary: US Customary System of Quantities
    17. Instances of qudt:ThermodynamicsQuantityKind
      1. quantity:AreaTemperature: Area Temperature
      2. quantity:AreaThermalExpansion: Area Thermal Expansion
      3. quantity:AreaTimeTemperature: Area Time Temperature
      4. quantity:CoefficientOfHeatTransfer: Coefficient of Heat Transfer
      5. quantity:CompressibilityFactor: Compressibility Factor
      6. quantity:EnergyPerTemperature: Energy per Temperature
      7. quantity:Enthalpy: Enthalpy
      8. quantity:Heat: Heat
      9. quantity:HeatCapacity: Heat Capacity
      10. quantity:HeatCapacityRatio: Heat Capacity Ratio
      11. quantity:HeatFlowRate: Heat Flow Rate
      12. quantity:HeatFlowRatePerUnitArea: Heat Flow Rate per Unit Area
      13. quantity:InverseLengthTemperature: Inverse Length Temperature
      14. quantity:InverseTimeTemperature: Inverse Time Temperature
      15. quantity:LengthTemperature: Length Temperature
      16. quantity:LengthTemperatureTime: Length Temperature Time
      17. quantity:LinearThermalExpansion: Linear Thermal Expansion
      18. quantity:MassTemperature: Mass Temperature
      19. quantity:MolarHeatCapacity: Molar Heat Capacity
      20. quantity:PowerPerAreaQuarticTemperature: Power per Area Quartic Temperature
      21. quantity:SpecificHeatCapacity: Specific Heat Capacity
      22. quantity:SpecificHeatPressure: Specific Heat Pressure
      23. quantity:SpecificHeatVolume: Specific Heat Volume
      24. quantity:TemperaturePerMagneticFluxDensity: Temperature per Magnetic Flux Density
      25. quantity:TemperaturePerTime: Temperature per Time
      26. quantity:ThermalConductivity: Thermal Conductivity
      27. quantity:ThermalDiffusivity: Thermal Diffusivity
      28. quantity:ThermalEfficiency: Thermal Efficiency
      29. quantity:ThermalEnergy: Thermal Energy
      30. quantity:ThermalEnergyLength: Thermal Energy Length
      31. quantity:ThermalInsulance: Thermal Insulance
      32. quantity:ThermalResistance: Thermal Resistance
      33. quantity:ThermalResistivity: Thermal Resistivity
      34. quantity:ThermodynamicEntropy: Thermodynamic Entropy
      35. quantity:ThermodynamicTemperature: Temperature
      36. quantity:TimeTemperature: Time Temperature
      37. quantity:VolumeThermalExpansion: Volume Thermal Expansion
      38. quantity:VolumetricHeatCapacity: Volumetric Heat Capacity
  7. NEXT

QUDT

Last modified
Table of contents
  1. Story
  2. Spotfire Dashboard
  3. Research Notes
  4. Slides
    1. Title Slide
      1. Slide 1 NASA QUDT Handbook
    2. Introductions
      1. Slide 2 Roadmap
      2. Slide 3 Introductions
      3. Slide 4 What is QUDT?
      4. Slide 5 Motivations for "Model Driven" QUDT 1
      5. Slide 6 Motivations for "Model Driven" QUDT 2
      6. Slide 7 Motivations for "Model Driven" QUDT 3
      7. Slide 8 Motivations for "Model Driven" QUDT 4
      8. Slide 9 Motivations for "Model Driven" QUDT 5
      9. Slide 10 QUDT: "Real World" Benefits 1
      10. Slide 11 QUDT: "Real World" Benefits 2
    3. Quantities, Units and Dimensions 101
      1. Slide 12 Roadmap
      2. Slide 13 Kinds of Physical Quantities
      3. Slide 14 of Measure
      4. Slide 15 Dimensions and Dimensional Analysis
      5. Slide 16 Quantities Need a Standard Vocabularly
    4. NASA QUDT Handbook
      1. Slide 17 Roadmap
      2. Slide 18 NASA QUDT Handbook HDBK-1003R
      3. Slide 19 Formal Model: Quantities and Units in OWL
      4. Slide 20 What is an Ontology? 1
      5. Slide 21 What is an Ontology? 2
      6. Slide 22 Key Requirements: QUDT Ontologies
      7. Slide 23 Benefits of QUDT Ontologies
    5. NASA QUDT Handbook
      1. Slide 24 Roadmap
      2. Slide 25 NASA QUDT Handbook HDBK-1003R
      3. Slide 26 QUDT Scope
      4. Slide 27 QUDT: "Real World" Benefits
      5. Slide 28 Applicability
      6. Slide 29 NASA QUDT Handbook: Content
      7. Slide 30 NASA QUDT Handbook: Quantity Kind Domains
      8. Slide 31 NASA QUDT Handbook: Example Propulsion Quantity Kinds
      9. Slide 32 NASA QUDT Handbook: Example An ISO-80000 QuantityKind
      10. Slide 33 QUDT Name, Identifier and Usage Rules
      11. Slide 34 Example of a Rule
      12. Slide 35 Model-Driven Traceability
      13. Slide 36 QUDT Industry & Standards Alignment
      14. Slide 37 QUDT Models ISO-80000
    6. QUDT Ontology Models
      1. Slide 38 Roadmap
      2. Slide 39 Conceptual Model of QUDT
      3. Slide 40 Conceptual Model of QUDT (Notes)
      4. Slide 41 QUDT Information Architecture
      5. Slide 42 Ontology Example: Quantity Kinds and Units (1)
      6. Slide 43 Ontology Example: Quantity Kinds and Units (2)
    7. How the QUDT Handbook Was Produced
      1. Slide 44 Roadmap
      2. Slide 45 How the QUDT Handbook Was Produced
      3. Slide 46 Example of Semantic Markup
    8. Next Priorities
      1. Slide 47 Roadmap
      2. Slide 48 Next Priorities
      3. Slide 49 How To Find Out More
      4. Slide 50 Thank You
  5. QUDT
    1. Overview
      1. Status
      2. Goals
    2. QUDT Ontologies and Vocabularies
      1. Ontology Class Structure
        1. Quantities, Quantity Kinds, and Quantity Values
        2. Quantity Kinds
        3. Unit of Measure
        4. Quantity Value
        5. Numerical Quantity Value
        6. Quantity Symbol
        7. Systems of Quantities and Units
        8. Base and Derived Quantity Kinds
        9. Quantity Dimensions
        10. Dimensionless Quantities and Units
        11. Allowed Units
        12. Example Quantity Kind and Unit Systems
        13. The SI System
        14. The CGS System
        15. CGS Units for Electricity and Magnetism
          1. EMU Derived Units
          2. ESU Derived Units
      2. Glossary
      3. Acknowledgements
      4. References
  6. Instances
    1. Instances of qudt:AtomicPhysicsQuantityKind
      1. quantity:AtomicCharge: Atomic Charge
      2. quantity:GyromagneticRatio: Gyromagnetic Ratio
      3. quantity:LinearEnergyTransfer: Linear Energy Transfer
    2. Instances of qudt:BiologyQuantityKind
      1. quantity:HeartRate: Heart Rate
      2. quantity:MicrobialFormation: Microbial Formation
      3. quantity:RespiratoryRate: Respiratory Rate
      4. quantity:SerumOrPlasmaLevel: Serum or Plasma Level
    3. Instances of qudt:ChemistryQuantityKind
      1. quantity:AmountOfSubstance: Amount of Substance
      2. quantity:AmountOfSubstancePerUnitMass: Amount of Substance per Unit Mass
      3. quantity:AmountOfSubstancePerUnitVolume: Amount of Substance Per Unit Volume
      4. quantity:CatalyticActivity: Catalytic Activity
      5. quantity:Concentration: Concentration
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:EnergyAndWorkPerMassAmountOfSubstance: Energy and Work per Mass Amount of Substance
      8. quantity:InverseAmountOfSubstance: Inverse Amount of Substance
      9. quantity:LengthMolarEnergy: Length Molar Energy
      10. quantity:MassAmountOfSubstance: Mass Amount of Substance
      11. quantity:MassAmountOfSubstanceTemperature: Mass Amount of Substance Temperature
      12. quantity:MolarEnergy: Molar Energy
      13. quantity:MolarMass: Molar Mass
      14. quantity:MolarVolume: Molar Volume
      15. quantity:MoleFraction: Mole Fraction
      16. quantity:MolecularMass: Molecular Mass
      17. quantity:TemperatureAmountOfSubstance: Temperature Amount of Substance
      18. quantity:Turbidity: Turbidity
    4. Instances of qudt:CommunicationsQuantityKind
      1. quantity:RF-Power: RF-Power
      2. quantity:SignalDetectionThreshold: Signal Detection Threshold
      3. quantity:SignalStrength: Signal Strength
    5. Instances of qudt:ElectricityAndMagnetismQuantityKind
      1. quantity:AuxillaryMagneticField: Auxillary Magnetic Field
      2. quantity:Capacitance: Capacitance
      3. quantity:CubicElectricDipoleMomentPerSquareEnergy: Cubic Electric Dipole Moment per Square Energy
      4. quantity:ElectricCharge: Electric Charge
      5. quantity:ElectricChargeLineDensity: Electric Charge Line Density
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:ElectricChargePerArea: Electric Charge per Unit Area
      8. quantity:ElectricChargePerMass: Electric Charge per Mass
      9. quantity:ElectricChargeVolumeDensity: Electric Charge Volume Density
      10. quantity:ElectricConductivity: Electric Conductivity
      11. quantity:ElectricCurrent: Electric Current
      12. quantity:ElectricCurrentDensity: Electric Current Density
      13. quantity:ElectricCurrentPerAngle: Electric Current per Angle
      14. quantity:ElectricCurrentPerUnitEnergy: Electric Current per Unit Energy
      15. quantity:ElectricCurrentPerUnitLength: Electric Current per Unit Length
      16. quantity:ElectricDipoleMoment: Electric Dipole Moment
      17. quantity:ElectricDisplacementField: Electric Displacement Field
      18. quantity:ElectricField: Electric Field
      19. quantity:ElectricFlux: Electric Flux
      20. quantity:ElectricPotential: Electric Potential
      21. quantity:ElectricPower: Electric Power
      22. quantity:ElectricQuadrupoleMoment: Electric Quadrupole Moment
      23. quantity:ElectromotiveForce: Electromotive Force
      24. quantity:EnergyPerAreaElectricCharge: Energy per Area Electric Charge
      25. quantity:EnergyPerElectricCharge: Energy per Electric Charge
      26. quantity:EnergyPerSquareMagneticFluxDensity: Energy per Square Magnetic Flux Density
      27. quantity:ForcePerElectricCharge: Force per Electric Charge
      28. quantity:Inductance: Inductance
      29. quantity:InverseMagneticFlux: Inverse Magnetic Flux
      30. quantity:InversePermittivity: Inverse Permittivity
      31. quantity:LengthPerUnitElectricCurrent: Length per Unit Electric Current
      32. quantity:LengthPerUnitMagneticFlux: Length per Unit Magnetic Flux
      33. quantity:MagneticDipoleMoment: Magnetic Dipole Moment
      34. quantity:MagneticField: Magnetic Field
      35. quantity:MagneticFlux: Magnetic Flux
      36. quantity:MagneticFluxPerUnitLength: Magnetic Flux per Unit Length
      37. quantity:MagnetizationField: Magnetization Field
      38. quantity:MagnetomotiveForce: Magnetomotive Force
      39. quantity:MassPerElectricCharge: Mass per Electric Charge
      40. quantity:Permeability: Permeability
      41. quantity:Permittivity: Permittivity
      42. quantity:Polarizability: Polarizability
      43. quantity:PolarizationField: Polarization Field
      44. quantity:PowerPerElectricCharge: Power per Electric Charge
      45. quantity:QuarticElectricDipoleMomentPerCubicEnergy: Quartic Electric Dipole Moment per Cubic Energy
      46. quantity:Resistance: Resistance
    6. Instances of qudt:FinancialQuantityKind
      1. quantity:Asset: Asset
      2. quantity:Currency: Currency
    7. Instances of qudt:FluidMechanicsQuantityKind
      1. quantity:AtmosphericPressure: Atmospheric Pressure
      2. quantity:Circulation: Circulation
      3. quantity:DynamicPressure: Dynamic Pressure
      4. quantity:DynamicViscosity: Dynamic Viscosity
      5. quantity:KinematicViscosity: Kinematic Viscosity
      6. quantity:MolecularViscosity: Molecular Viscosity
      7. quantity:Pressure: Pressure
      8. quantity:ReynoldsNumber: Reynolds Number
      9. quantity:StaticPressure: Static Pressure
      10. quantity:TotalPressure: Total Pressure
      11. quantity:Viscosity: Viscosity
      12. quantity:Vorticity: Vorticity
    8. Instances of qudt:InformationQuantityKind
      1. quantity:Capacity: Capacity
      2. quantity:DataRate: Data Rate
      3. quantity:InformationEntropy: Information Entropy
      4. quantity:VideoFrameRate: Video Frame Rate
    9. Instances of qudt:MechanicsQuantityKind
      1. quantity:AngularMomentum: Angular Momentum
      2. quantity:AreaPerTime: Area per Time
      3. quantity:Density: Density
      4. quantity:EnergyAndWork: Energy and Work
      5. quantity:EnergyDensity: Energy Density
      6. quantity:EnergyInternal: Internal Energy
      7. quantity:EnergyKinetic: Kinetic Energy
      8. quantity:EnergyPerArea: Energy per Area
      9. quantity:Force: Force
      10. quantity:ForceMagnitude: Force Magnitude
      11. quantity:ForcePerArea: Force Per Area
      12. quantity:ForcePerAreaTime: Force Per Area Time
      13. quantity:ForcePerLength: Force per Unit Length
      14. quantity:Friction: Friction
      15. quantity:GravitationalAttraction: Gravitational Attraction
      16. quantity:InverseEnergy: Inverse Energy
      17. quantity:InverseSquareEnergy: Inverse Square Energy
      18. quantity:KineticEnergy: Kinetic Energy
      19. quantity:LengthByForce: Length Force
      20. quantity:LengthEnergy: Length Energy
      21. quantity:LengthMass: Length Mass
      22. quantity:LinearMomentum: Linear Momentum
      23. quantity:Mass: Mass
      24. quantity:MassPerArea: Mass per Area
      25. quantity:MassPerAreaTime: Mass per Area Time
      26. quantity:MassPerLength: Mass per Length
      27. quantity:MassPerTime: Mass per Time
      28. quantity:MolarAngularMomentum: Molar Angular Momentum
      29. quantity:MomentOfInertia: Moment of Inertia
      30. quantity:Momentum: Momentum
      31. quantity:PolarMomentOfInertia: Polar moment of inertia
      32. quantity:PotentialEnergy: Potential Energy
      33. quantity:Power: Power
      34. quantity:PowerArea: Power Area
      35. quantity:PowerAreaPerSolidAngle: Power Area per Solid Angle
      36. quantity:PowerPerArea: Power per Area
      37. quantity:PowerPerAreaAngle: Power per Area Angle
      38. quantity:SpecificEnergy: Specific Energy
      39. quantity:SpecificImpulseByMass: Specific Impulse by Mass
      40. quantity:SpecificImpulseByWeight: Specific Impulse by Weight
      41. quantity:SpecificVolume: Specific Volume
      42. quantity:SquareEnergy: Square Energy
      43. quantity:StandardGravitationalParameter: Standard Gravitational Parameter
      44. quantity:Thrust: Thrust
      45. quantity:ThrustToMassRatio: Thrust to Mass Ratio
      46. quantity:Torque: Torque
      47. quantity:Weight: Weight
    10. Instances of qudt:PhotometryQuantityKind
      1. quantity:Illuminance: Illuminance
      2. quantity:Luminance: Luminance
      3. quantity:LuminousEfficacy: Luminous Efficacy
      4. quantity:LuminousEmmitance: Luminous Emmitance
      5. quantity:LuminousEnergy: Luminous Energy
      6. quantity:LuminousFlux: Luminous Flux
      7. quantity:LuminousFluxPerArea: Luminous Flux per Area
      8. quantity:LuminousIntensity: Luminous Intensity
    11. Instances of qudt:QuantityKind
      1. quantity:AbsoluteHumidity: Absolute Humidity
      2. quantity:Dimensionless: Dimensionless
      3. quantity:DimensionlessRatio: Dimensionless Ratio
      4. quantity:Gain: Gain
    12. Instances of qudt:QuantumMechanicsQuantityKind
      1. quantity:Action: Action
      2. quantity:Activity: Activity
    13. Instances of qudt:RadiologyQuantityKind
      1. quantity:AbsorbedDose: Absorbed Dose
      2. quantity:AbsorbedDoseRate: Absorbed Dose Rate
      3. quantity:DoseEquivalent: Dose Equivalent
      4. quantity:Exposure: Exposure
    14. Instances of qudt:RadiometryQuantityKind
      1. quantity:Irradiance: Irradiance
      2. quantity:Radiance: Radiance
      3. quantity:RadiantEmmitance: Radiant Emmitance
      4. quantity:RadiantEnergy: Radiant Energy
      5. quantity:RadiantFlux: Radiant Flux
      6. quantity:RadiantIntensity: Radiant Intensity
      7. quantity:Radiosity: Radiosity
      8. quantity:FirstMomentOfArea: First Moment of Area
      9. quantity:SecondMomentOfArea: Second Moment of Area
      10. quantity:Strain: Strain
      11. quantity:StrainEnergyDensity: Strain Energy Density
      12. quantity:Stress: Stress
      13. quantity:Tension: Tension
    15. Instances of qudt:SpaceAndTimeQuantityKind
      1. quantity:Acceleration: Acceleration
      2. quantity:Angle: Angle
      3. quantity:AngularAcceleration: Angular Acceleration
      4. quantity:AngularFrequency: Angular Frequency
      5. quantity:AngularVelocity: Angular Velocity
      6. quantity:Area: Area
      7. quantity:AreaAngle: Area Angle
      8. quantity:AreaTime: Area Time
      9. quantity:Curvature: Curvature
      10. quantity:DryVolume: Dry Volume
      11. quantity:Frequency: Frequency
      12. quantity:InverseLength: Inverse Length
      13. quantity:InverseVolume: Inverse Volume
      14. quantity:Length: Length
      15. quantity:LinearAcceleration: Linear Acceleration
      16. quantity:LinearVelocity: Linear Velocity
      17. quantity:LiquidVolume: Liquid Volume
      18. quantity:MachNumber: Mach Number
      19. quantity:NumberDensity: Number Density
      20. quantity:PlaneAngle: Plane Angle
      21. quantity:SolidAngle: Solid Angle
      22. quantity:Speed: Speed
      23. quantity:StochasticProcess: Stochastic Process
      24. quantity:Time: Time
      25. quantity:TimeSquared: Time Squared
      26. quantity:Velocity: Velocity
      27. quantity:Volume: Volume
      28. quantity:VolumePerUnitTime: Volume per Unit Time
    16. Instances of qudt:SystemOfQuantities
      1. quantity:SystemOfQuantities_CGS: CGS System of Quantities
      2. quantity:SystemOfQuantities_CGS-EMU: CGS-EMU System of Quantities
      3. quantity:SystemOfQuantities_CGS-ESU: CGS-ESU System of Quantities
      4. quantity:SystemOfQuantities_CGS-Gauss: CGS-Gauss System of Quantities
      5. quantity:SystemOfQuantities_Planck: Planck System of Quantities
      6. quantity:SystemOfQuantities_SI: International System of Quantities
      7. quantity:SystemOfQuantities_USCustomary: US Customary System of Quantities
    17. Instances of qudt:ThermodynamicsQuantityKind
      1. quantity:AreaTemperature: Area Temperature
      2. quantity:AreaThermalExpansion: Area Thermal Expansion
      3. quantity:AreaTimeTemperature: Area Time Temperature
      4. quantity:CoefficientOfHeatTransfer: Coefficient of Heat Transfer
      5. quantity:CompressibilityFactor: Compressibility Factor
      6. quantity:EnergyPerTemperature: Energy per Temperature
      7. quantity:Enthalpy: Enthalpy
      8. quantity:Heat: Heat
      9. quantity:HeatCapacity: Heat Capacity
      10. quantity:HeatCapacityRatio: Heat Capacity Ratio
      11. quantity:HeatFlowRate: Heat Flow Rate
      12. quantity:HeatFlowRatePerUnitArea: Heat Flow Rate per Unit Area
      13. quantity:InverseLengthTemperature: Inverse Length Temperature
      14. quantity:InverseTimeTemperature: Inverse Time Temperature
      15. quantity:LengthTemperature: Length Temperature
      16. quantity:LengthTemperatureTime: Length Temperature Time
      17. quantity:LinearThermalExpansion: Linear Thermal Expansion
      18. quantity:MassTemperature: Mass Temperature
      19. quantity:MolarHeatCapacity: Molar Heat Capacity
      20. quantity:PowerPerAreaQuarticTemperature: Power per Area Quartic Temperature
      21. quantity:SpecificHeatCapacity: Specific Heat Capacity
      22. quantity:SpecificHeatPressure: Specific Heat Pressure
      23. quantity:SpecificHeatVolume: Specific Heat Volume
      24. quantity:TemperaturePerMagneticFluxDensity: Temperature per Magnetic Flux Density
      25. quantity:TemperaturePerTime: Temperature per Time
      26. quantity:ThermalConductivity: Thermal Conductivity
      27. quantity:ThermalDiffusivity: Thermal Diffusivity
      28. quantity:ThermalEfficiency: Thermal Efficiency
      29. quantity:ThermalEnergy: Thermal Energy
      30. quantity:ThermalEnergyLength: Thermal Energy Length
      31. quantity:ThermalInsulance: Thermal Insulance
      32. quantity:ThermalResistance: Thermal Resistance
      33. quantity:ThermalResistivity: Thermal Resistivity
      34. quantity:ThermodynamicEntropy: Thermodynamic Entropy
      35. quantity:ThermodynamicTemperature: Temperature
      36. quantity:TimeTemperature: Time Temperature
      37. quantity:VolumeThermalExpansion: Volume Thermal Expansion
      38. quantity:VolumetricHeatCapacity: Volumetric Heat Capacity
  7. NEXT

  1. Story
  2. Spotfire Dashboard
  3. Research Notes
  4. Slides
    1. Title Slide
      1. Slide 1 NASA QUDT Handbook
    2. Introductions
      1. Slide 2 Roadmap
      2. Slide 3 Introductions
      3. Slide 4 What is QUDT?
      4. Slide 5 Motivations for "Model Driven" QUDT 1
      5. Slide 6 Motivations for "Model Driven" QUDT 2
      6. Slide 7 Motivations for "Model Driven" QUDT 3
      7. Slide 8 Motivations for "Model Driven" QUDT 4
      8. Slide 9 Motivations for "Model Driven" QUDT 5
      9. Slide 10 QUDT: "Real World" Benefits 1
      10. Slide 11 QUDT: "Real World" Benefits 2
    3. Quantities, Units and Dimensions 101
      1. Slide 12 Roadmap
      2. Slide 13 Kinds of Physical Quantities
      3. Slide 14 of Measure
      4. Slide 15 Dimensions and Dimensional Analysis
      5. Slide 16 Quantities Need a Standard Vocabularly
    4. NASA QUDT Handbook
      1. Slide 17 Roadmap
      2. Slide 18 NASA QUDT Handbook HDBK-1003R
      3. Slide 19 Formal Model: Quantities and Units in OWL
      4. Slide 20 What is an Ontology? 1
      5. Slide 21 What is an Ontology? 2
      6. Slide 22 Key Requirements: QUDT Ontologies
      7. Slide 23 Benefits of QUDT Ontologies
    5. NASA QUDT Handbook
      1. Slide 24 Roadmap
      2. Slide 25 NASA QUDT Handbook HDBK-1003R
      3. Slide 26 QUDT Scope
      4. Slide 27 QUDT: "Real World" Benefits
      5. Slide 28 Applicability
      6. Slide 29 NASA QUDT Handbook: Content
      7. Slide 30 NASA QUDT Handbook: Quantity Kind Domains
      8. Slide 31 NASA QUDT Handbook: Example Propulsion Quantity Kinds
      9. Slide 32 NASA QUDT Handbook: Example An ISO-80000 QuantityKind
      10. Slide 33 QUDT Name, Identifier and Usage Rules
      11. Slide 34 Example of a Rule
      12. Slide 35 Model-Driven Traceability
      13. Slide 36 QUDT Industry & Standards Alignment
      14. Slide 37 QUDT Models ISO-80000
    6. QUDT Ontology Models
      1. Slide 38 Roadmap
      2. Slide 39 Conceptual Model of QUDT
      3. Slide 40 Conceptual Model of QUDT (Notes)
      4. Slide 41 QUDT Information Architecture
      5. Slide 42 Ontology Example: Quantity Kinds and Units (1)
      6. Slide 43 Ontology Example: Quantity Kinds and Units (2)
    7. How the QUDT Handbook Was Produced
      1. Slide 44 Roadmap
      2. Slide 45 How the QUDT Handbook Was Produced
      3. Slide 46 Example of Semantic Markup
    8. Next Priorities
      1. Slide 47 Roadmap
      2. Slide 48 Next Priorities
      3. Slide 49 How To Find Out More
      4. Slide 50 Thank You
  5. QUDT
    1. Overview
      1. Status
      2. Goals
    2. QUDT Ontologies and Vocabularies
      1. Ontology Class Structure
        1. Quantities, Quantity Kinds, and Quantity Values
        2. Quantity Kinds
        3. Unit of Measure
        4. Quantity Value
        5. Numerical Quantity Value
        6. Quantity Symbol
        7. Systems of Quantities and Units
        8. Base and Derived Quantity Kinds
        9. Quantity Dimensions
        10. Dimensionless Quantities and Units
        11. Allowed Units
        12. Example Quantity Kind and Unit Systems
        13. The SI System
        14. The CGS System
        15. CGS Units for Electricity and Magnetism
          1. EMU Derived Units
          2. ESU Derived Units
      2. Glossary
      3. Acknowledgements
      4. References
  6. Instances
    1. Instances of qudt:AtomicPhysicsQuantityKind
      1. quantity:AtomicCharge: Atomic Charge
      2. quantity:GyromagneticRatio: Gyromagnetic Ratio
      3. quantity:LinearEnergyTransfer: Linear Energy Transfer
    2. Instances of qudt:BiologyQuantityKind
      1. quantity:HeartRate: Heart Rate
      2. quantity:MicrobialFormation: Microbial Formation
      3. quantity:RespiratoryRate: Respiratory Rate
      4. quantity:SerumOrPlasmaLevel: Serum or Plasma Level
    3. Instances of qudt:ChemistryQuantityKind
      1. quantity:AmountOfSubstance: Amount of Substance
      2. quantity:AmountOfSubstancePerUnitMass: Amount of Substance per Unit Mass
      3. quantity:AmountOfSubstancePerUnitVolume: Amount of Substance Per Unit Volume
      4. quantity:CatalyticActivity: Catalytic Activity
      5. quantity:Concentration: Concentration
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:EnergyAndWorkPerMassAmountOfSubstance: Energy and Work per Mass Amount of Substance
      8. quantity:InverseAmountOfSubstance: Inverse Amount of Substance
      9. quantity:LengthMolarEnergy: Length Molar Energy
      10. quantity:MassAmountOfSubstance: Mass Amount of Substance
      11. quantity:MassAmountOfSubstanceTemperature: Mass Amount of Substance Temperature
      12. quantity:MolarEnergy: Molar Energy
      13. quantity:MolarMass: Molar Mass
      14. quantity:MolarVolume: Molar Volume
      15. quantity:MoleFraction: Mole Fraction
      16. quantity:MolecularMass: Molecular Mass
      17. quantity:TemperatureAmountOfSubstance: Temperature Amount of Substance
      18. quantity:Turbidity: Turbidity
    4. Instances of qudt:CommunicationsQuantityKind
      1. quantity:RF-Power: RF-Power
      2. quantity:SignalDetectionThreshold: Signal Detection Threshold
      3. quantity:SignalStrength: Signal Strength
    5. Instances of qudt:ElectricityAndMagnetismQuantityKind
      1. quantity:AuxillaryMagneticField: Auxillary Magnetic Field
      2. quantity:Capacitance: Capacitance
      3. quantity:CubicElectricDipoleMomentPerSquareEnergy: Cubic Electric Dipole Moment per Square Energy
      4. quantity:ElectricCharge: Electric Charge
      5. quantity:ElectricChargeLineDensity: Electric Charge Line Density
      6. quantity:ElectricChargePerAmountOfSubstance: Electric Charge per Amount of Substance
      7. quantity:ElectricChargePerArea: Electric Charge per Unit Area
      8. quantity:ElectricChargePerMass: Electric Charge per Mass
      9. quantity:ElectricChargeVolumeDensity: Electric Charge Volume Density
      10. quantity:ElectricConductivity: Electric Conductivity
      11. quantity:ElectricCurrent: Electric Current
      12. quantity:ElectricCurrentDensity: Electric Current Density
      13. quantity:ElectricCurrentPerAngle: Electric Current per Angle
      14. quantity:ElectricCurrentPerUnitEnergy: Electric Current per Unit Energy
      15. quantity:ElectricCurrentPerUnitLength: Electric Current per Unit Length
      16. quantity:ElectricDipoleMoment: Electric Dipole Moment
      17. quantity:ElectricDisplacementField: Electric Displacement Field
      18. quantity:ElectricField: Electric Field
      19. quantity:ElectricFlux: Electric Flux
      20. quantity:ElectricPotential: Electric Potential
      21. quantity:ElectricPower: Electric Power
      22. quantity:ElectricQuadrupoleMoment: Electric Quadrupole Moment
      23. quantity:ElectromotiveForce: Electromotive Force
      24. quantity:EnergyPerAreaElectricCharge: Energy per Area Electric Charge
      25. quantity:EnergyPerElectricCharge: Energy per Electric Charge
      26. quantity:EnergyPerSquareMagneticFluxDensity: Energy per Square Magnetic Flux Density
      27. quantity:ForcePerElectricCharge: Force per Electric Charge
      28. quantity:Inductance: Inductance
      29. quantity:InverseMagneticFlux: Inverse Magnetic Flux
      30. quantity:InversePermittivity: Inverse Permittivity
      31. quantity:LengthPerUnitElectricCurrent: Length per Unit Electric Current
      32. quantity:LengthPerUnitMagneticFlux: Length per Unit Magnetic Flux
      33. quantity:MagneticDipoleMoment: Magnetic Dipole Moment
      34. quantity:MagneticField: Magnetic Field
      35. quantity:MagneticFlux: Magnetic Flux
      36. quantity:MagneticFluxPerUnitLength: Magnetic Flux per Unit Length
      37. quantity:MagnetizationField: Magnetization Field
      38. quantity:MagnetomotiveForce: Magnetomotive Force
      39. quantity:MassPerElectricCharge: Mass per Electric Charge
      40. quantity:Permeability: Permeability
      41. quantity:Permittivity: Permittivity
      42. quantity:Polarizability: Polarizability
      43. quantity:PolarizationField: Polarization Field
      44. quantity:PowerPerElectricCharge: Power per Electric Charge
      45. quantity:QuarticElectricDipoleMomentPerCubicEnergy: Quartic Electric Dipole Moment per Cubic Energy
      46. quantity:Resistance: Resistance
    6. Instances of qudt:FinancialQuantityKind
      1. quantity:Asset: Asset
      2. quantity:Currency: Currency
    7. Instances of qudt:FluidMechanicsQuantityKind
      1. quantity:AtmosphericPressure: Atmospheric Pressure
      2. quantity:Circulation: Circulation
      3. quantity:DynamicPressure: Dynamic Pressure
      4. quantity:DynamicViscosity: Dynamic Viscosity
      5. quantity:KinematicViscosity: Kinematic Viscosity
      6. quantity:MolecularViscosity: Molecular Viscosity
      7. quantity:Pressure: Pressure
      8. quantity:ReynoldsNumber: Reynolds Number
      9. quantity:StaticPressure: Static Pressure
      10. quantity:TotalPressure: Total Pressure
      11. quantity:Viscosity: Viscosity
      12. quantity:Vorticity: Vorticity
    8. Instances of qudt:InformationQuantityKind
      1. quantity:Capacity: Capacity
      2. quantity:DataRate: Data Rate
      3. quantity:InformationEntropy: Information Entropy
      4. quantity:VideoFrameRate: Video Frame Rate
    9. Instances of qudt:MechanicsQuantityKind
      1. quantity:AngularMomentum: Angular Momentum
      2. quantity:AreaPerTime: Area per Time
      3. quantity:Density: Density
      4. quantity:EnergyAndWork: Energy and Work
      5. quantity:EnergyDensity: Energy Density
      6. quantity:EnergyInternal: Internal Energy
      7. quantity:EnergyKinetic: Kinetic Energy
      8. quantity:EnergyPerArea: Energy per Area
      9. quantity:Force: Force
      10. quantity:ForceMagnitude: Force Magnitude
      11. quantity:ForcePerArea: Force Per Area
      12. quantity:ForcePerAreaTime: Force Per Area Time
      13. quantity:ForcePerLength: Force per Unit Length
      14. quantity:Friction: Friction
      15. quantity:GravitationalAttraction: Gravitational Attraction
      16. quantity:InverseEnergy: Inverse Energy
      17. quantity:InverseSquareEnergy: Inverse Square Energy
      18. quantity:KineticEnergy: Kinetic Energy
      19. quantity:LengthByForce: Length Force
      20. quantity:LengthEnergy: Length Energy
      21. quantity:LengthMass: Length Mass
      22. quantity:LinearMomentum: Linear Momentum
      23. quantity:Mass: Mass
      24. quantity:MassPerArea: Mass per Area
      25. quantity:MassPerAreaTime: Mass per Area Time
      26. quantity:MassPerLength: Mass per Length
      27. quantity:MassPerTime: Mass per Time
      28. quantity:MolarAngularMomentum: Molar Angular Momentum
      29. quantity:MomentOfInertia: Moment of Inertia
      30. quantity:Momentum: Momentum
      31. quantity:PolarMomentOfInertia: Polar moment of inertia
      32. quantity:PotentialEnergy: Potential Energy
      33. quantity:Power: Power
      34. quantity:PowerArea: Power Area
      35. quantity:PowerAreaPerSolidAngle: Power Area per Solid Angle
      36. quantity:PowerPerArea: Power per Area
      37. quantity:PowerPerAreaAngle: Power per Area Angle
      38. quantity:SpecificEnergy: Specific Energy
      39. quantity:SpecificImpulseByMass: Specific Impulse by Mass
      40. quantity:SpecificImpulseByWeight: Specific Impulse by Weight
      41. quantity:SpecificVolume: Specific Volume
      42. quantity:SquareEnergy: Square Energy
      43. quantity:StandardGravitationalParameter: Standard Gravitational Parameter
      44. quantity:Thrust: Thrust
      45. quantity:ThrustToMassRatio: Thrust to Mass Ratio
      46. quantity:Torque: Torque
      47. quantity:Weight: Weight
    10. Instances of qudt:PhotometryQuantityKind
      1. quantity:Illuminance: Illuminance
      2. quantity:Luminance: Luminance
      3. quantity:LuminousEfficacy: Luminous Efficacy
      4. quantity:LuminousEmmitance: Luminous Emmitance
      5. quantity:LuminousEnergy: Luminous Energy
      6. quantity:LuminousFlux: Luminous Flux
      7. quantity:LuminousFluxPerArea: Luminous Flux per Area
      8. quantity:LuminousIntensity: Luminous Intensity
    11. Instances of qudt:QuantityKind
      1. quantity:AbsoluteHumidity: Absolute Humidity
      2. quantity:Dimensionless: Dimensionless
      3. quantity:DimensionlessRatio: Dimensionless Ratio
      4. quantity:Gain: Gain
    12. Instances of qudt:QuantumMechanicsQuantityKind
      1. quantity:Action: Action
      2. quantity:Activity: Activity
    13. Instances of qudt:RadiologyQuantityKind
      1. quantity:AbsorbedDose: Absorbed Dose
      2. quantity:AbsorbedDoseRate: Absorbed Dose Rate
      3. quantity:DoseEquivalent: Dose Equivalent
      4. quantity:Exposure: Exposure
    14. Instances of qudt:RadiometryQuantityKind
      1. quantity:Irradiance: Irradiance
      2. quantity:Radiance: Radiance
      3. quantity:RadiantEmmitance: Radiant Emmitance
      4. quantity:RadiantEnergy: Radiant Energy
      5. quantity:RadiantFlux: Radiant Flux
      6. quantity:RadiantIntensity: Radiant Intensity
      7. quantity:Radiosity: Radiosity
      8. quantity:FirstMomentOfArea: First Moment of Area
      9. quantity:SecondMomentOfArea: Second Moment of Area
      10. quantity:Strain: Strain
      11. quantity:StrainEnergyDensity: Strain Energy Density
      12. quantity:Stress: Stress
      13. quantity:Tension: Tension
    15. Instances of qudt:SpaceAndTimeQuantityKind
      1. quantity:Acceleration: Acceleration
      2. quantity:Angle: Angle
      3. quantity:AngularAcceleration: Angular Acceleration
      4. quantity:AngularFrequency: Angular Frequency
      5. quantity:AngularVelocity: Angular Velocity
      6. quantity:Area: Area
      7. quantity:AreaAngle: Area Angle
      8. quantity:AreaTime: Area Time
      9. quantity:Curvature: Curvature
      10. quantity:DryVolume: Dry Volume
      11. quantity:Frequency: Frequency
      12. quantity:InverseLength: Inverse Length
      13. quantity:InverseVolume: Inverse Volume
      14. quantity:Length: Length
      15. quantity:LinearAcceleration: Linear Acceleration
      16. quantity:LinearVelocity: Linear Velocity
      17. quantity:LiquidVolume: Liquid Volume
      18. quantity:MachNumber: Mach Number
      19. quantity:NumberDensity: Number Density
      20. quantity:PlaneAngle: Plane Angle
      21. quantity:SolidAngle: Solid Angle
      22. quantity:Speed: Speed
      23. quantity:StochasticProcess: Stochastic Process
      24. quantity:Time: Time
      25. quantity:TimeSquared: Time Squared
      26. quantity:Velocity: Velocity
      27. quantity:Volume: Volume
      28. quantity:VolumePerUnitTime: Volume per Unit Time
    16. Instances of qudt:SystemOfQuantities
      1. quantity:SystemOfQuantities_CGS: CGS System of Quantities
      2. quantity:SystemOfQuantities_CGS-EMU: CGS-EMU System of Quantities
      3. quantity:SystemOfQuantities_CGS-ESU: CGS-ESU System of Quantities
      4. quantity:SystemOfQuantities_CGS-Gauss: CGS-Gauss System of Quantities
      5. quantity:SystemOfQuantities_Planck: Planck System of Quantities
      6. quantity:SystemOfQuantities_SI: International System of Quantities
      7. quantity:SystemOfQuantities_USCustomary: US Customary System of Quantities
    17. Instances of qudt:ThermodynamicsQuantityKind
      1. quantity:AreaTemperature: Area Temperature
      2. quantity:AreaThermalExpansion: Area Thermal Expansion
      3. quantity:AreaTimeTemperature: Area Time Temperature
      4. quantity:CoefficientOfHeatTransfer: Coefficient of Heat Transfer
      5. quantity:CompressibilityFactor: Compressibility Factor
      6. quantity:EnergyPerTemperature: Energy per Temperature
      7. quantity:Enthalpy: Enthalpy
      8. quantity:Heat: Heat
      9. quantity:HeatCapacity: Heat Capacity
      10. quantity:HeatCapacityRatio: Heat Capacity Ratio
      11. quantity:HeatFlowRate: Heat Flow Rate
      12. quantity:HeatFlowRatePerUnitArea: Heat Flow Rate per Unit Area
      13. quantity:InverseLengthTemperature: Inverse Length Temperature
      14. quantity:InverseTimeTemperature: Inverse Time Temperature
      15. quantity:LengthTemperature: Length Temperature
      16. quantity:LengthTemperatureTime: Length Temperature Time
      17. quantity:LinearThermalExpansion: Linear Thermal Expansion
      18. quantity:MassTemperature: Mass Temperature
      19. quantity:MolarHeatCapacity: Molar Heat Capacity
      20. quantity:PowerPerAreaQuarticTemperature: Power per Area Quartic Temperature
      21. quantity:SpecificHeatCapacity: Specific Heat Capacity
      22. quantity:SpecificHeatPressure: Specific Heat Pressure
      23. quantity:SpecificHeatVolume: Specific Heat Volume
      24. quantity:TemperaturePerMagneticFluxDensity: Temperature per Magnetic Flux Density
      25. quantity:TemperaturePerTime: Temperature per Time
      26. quantity:ThermalConductivity: Thermal Conductivity
      27. quantity:ThermalDiffusivity: Thermal Diffusivity
      28. quantity:ThermalEfficiency: Thermal Efficiency
      29. quantity:ThermalEnergy: Thermal Energy
      30. quantity:ThermalEnergyLength: Thermal Energy Length
      31. quantity:ThermalInsulance: Thermal Insulance
      32. quantity:ThermalResistance: Thermal Resistance
      33. quantity:ThermalResistivity: Thermal Resistivity
      34. quantity:ThermodynamicEntropy: Thermodynamic Entropy
      35. quantity:ThermodynamicTemperature: Temperature
      36. quantity:TimeTemperature: Time Temperature
      37. quantity:VolumeThermalExpansion: Volume Thermal Expansion
      38. quantity:VolumetricHeatCapacity: Volumetric Heat Capacity
  7. NEXT

Story

Data Science for QUDT

The QUDT Ontologies, and derived XML Vocabularies, are being developed by TopQuadrant and NASA. Originally, they were developed for the NASA Exploration Initiatives Ontology Models (NExIOM) project, a Constellation Program initiative at the AMES Research Center (ARC). They now are the basis of the NASA QUDT Handbook to be published by NASA Headquarters.

The results are:

  • QUDT - Quantities, Units, Dimensions and Data Types Ontologies: http://www.qudt.org/
    • Last UPDATED August 24, 2013
  • QUDT -Quantities, Units, Dimensions and dataTypes - public repository: https://github.com/qudt/qudt-public-repo
    • Last updated: May 4, 2014
  • NASA QUDT Handbook PowerPoint Slides
    • October 10, 2013

Data Science can repurpose this into a NASA Data Science Data Publication. The results are:

Knowledge Base (this page): Use Google Chrome Find

Spreadsheet: Use Excel Find

Spotfire: Use Spotfire Find

Additional Refinements:

  • Add Unit Instances: DONE
  • Redirect the Internal URLs: IN PROCESS
  • Other: Slides

Conclusions and Recommendations

  • Since 2009, NASA has been developing a machine-processable representation of Quantities, Units of Measure and Data Types (QUDT). Source: Hodgson, 2014, Presentation.
  • The NASA QUDT Handbook (HDBK-1003R) which, now over 3,500 pages, is generated from the QUDT models. Source: Hodgson, 2014, Presentation.
  • The TopQuadrant work on QUDT and the NASA QUDT Handbook work seems to have stalled.
  • The Semantic Community Data Science Audit of the TopQuadrant work on QUDT found some gaps and errors, which we are currently trying to understand and fix.
  • The QUDT needs to be rendered in a MindTouch, Excel, and Spotfire Data Science Data Publication to be more reuseable, which we have started.

Spotfire Dashboard

For Internet Explorer Users and Those Wanting Full Screen Display Use: Web Player Get Spotfire iPad App

Research Notes

http://www.qudt.org/

https://github.com/qudt/qudt-public-repo

http://ontolog.cim3.net%2Ffile%2Fwork%2FOntologyBasedStandards%2F2013-10-10_Case-for-QUOMOS%2FNASA-QUDT-Handbook-v10--RalphHodgson_20131010.pdf

http://ontolog.cim3.net/cgi-bin/wiki...UDT&dosearch=1

http://ontolog.cim3.net/cgi-bin/wiki.pl?RalphHodgson

Slides

Slides (PDF)

Title Slide

Slide 1 NASA QUDT Handbook

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Introductions

Slide 2 Roadmap

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Slide 3 Introductions

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Slide 4 What is QUDT?

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Slide 5 Motivations for "Model Driven" QUDT 1

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Slide 6 Motivations for "Model Driven" QUDT 2

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Slide 7 Motivations for "Model Driven" QUDT 3

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Slide 8 Motivations for "Model Driven" QUDT 4

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Slide 9 Motivations for "Model Driven" QUDT 5

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Slide 10 QUDT: "Real World" Benefits 1

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Slide 11 QUDT: "Real World" Benefits 2

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Quantities, Units and Dimensions 101

Slide 12 Roadmap

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Slide 13 Kinds of Physical Quantities

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Slide 14 of Measure

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Slide 15 Dimensions and Dimensional Analysis

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Slide 16 Quantities Need a Standard Vocabularly

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NASA QUDT Handbook

Slide 17 Roadmap

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Slide 18 NASA QUDT Handbook HDBK-1003R

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Slide 19 Formal Model: Quantities and Units in OWL

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Slide 20 What is an Ontology? 1

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Slide 21 What is an Ontology? 2

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Slide 22 Key Requirements: QUDT Ontologies

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Slide 23 Benefits of QUDT Ontologies

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NASA QUDT Handbook

Slide 24 Roadmap

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Slide 25 NASA QUDT Handbook HDBK-1003R

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Slide 26 QUDT Scope

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Slide 27 QUDT: "Real World" Benefits

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Slide 28 Applicability

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Slide 29 NASA QUDT Handbook: Content

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Slide 30 NASA QUDT Handbook: Quantity Kind Domains

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Slide 31 NASA QUDT Handbook: Example Propulsion Quantity Kinds

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Slide 32 NASA QUDT Handbook: Example An ISO-80000 QuantityKind

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Slide 33 QUDT Name, Identifier and Usage Rules

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Slide 34 Example of a Rule

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Slide 35 Model-Driven Traceability

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Slide 36 QUDT Industry & Standards Alignment

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Slide 37 QUDT Models ISO-80000

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QUDT Ontology Models

Slide 38 Roadmap

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Slide 39 Conceptual Model of QUDT

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Slide 40 Conceptual Model of QUDT (Notes)

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Slide 41 QUDT Information Architecture

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Slide 42 Ontology Example: Quantity Kinds and Units (1)

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Slide 43 Ontology Example: Quantity Kinds and Units (2)

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How the QUDT Handbook Was Produced

Slide 44 Roadmap

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Slide 45 How the QUDT Handbook Was Produced

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Slide 46 Example of Semantic Markup

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Next Priorities

Slide 47 Roadmap

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Slide 48 Next Priorities

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Slide 49 How To Find Out More

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Slide 50 Thank You

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QUDT

Source: http://www.qudt.org/

Quantities, Units, Dimensions and Data Types Ontologies

March 18, 2014

Authors:
Ralph Hodgson, TopQuadrant, Inc.
Paul J. Keller, NASA AMES Research Center
Jack Hodges
Jack Spivak

Overview

The QUDT Ontologies, and derived XML Vocabularies, are being developed by TopQuadrant and NASA. Originally, they were developed for the NASA Exploration Initiatives Ontology Models (NExIOM) project, a ConstellationPROGRAM initiative at the AMES Research Center (ARC). They now for the basis of the NASA QUDT Handbook to be published by NASA Headquarters.

Status

The current release of the QUDT ontologies is version 1.1 and may be DOWNLOADED from the QUDT Catalog, which can also be accessed from LinkedModel.org.

Release 2 of QUDT will be published incrementally. Currently the content, in the form of the NASA QUDT Handbook, is being reviewed by NASA.

A presentation on QUDT can be found at scribd.com/ralphtq.

Goals

The goals of QUDT are to provide:

  1. A standardized consistent vocabulary, focused on terminology used in science and engineering.
    1. The vocabulary in this standard consists of standardized terminology, definitions, identifiers, and information models.
    2. The intent is to use this vocabulary with a variety of encodings, formats, and data definitions, so it is defined independent of those forms.
    3. Some or all portions of this vocabulary will be of interest to various users and applications, depending on the use case and policy mandates.
    4. It is expected that a large set of existing corpus will not be changed, and so this standard serves as a critical “Rosetta Stone” to reference existing uses of quantities, units, dimensions, and types to a consistent base.
  2. A set of consistent coded identifiers, for human and machine use.
    1. In the same way that modern digital COMPUTERS could not represent and process meaningful information without the use of standards such as ASCII and Unicode, this standard also introduces a similar coding scheme, for a like purpose.
    2. Assigning an explicit designator (e.g. ASCII uses a numerical value for each letter of the alphabet, numbers, and punctuation) to quantities, units, dimensions, and types is used to provide a robust, unequivocal method of identification of digital information by computer SOFTWARE and hardware.
    3. This definitional approach provides generalized usability for both humans and machines, avoiding problems with uncertainty and misinterpretation.
  3. A collection of foundational vocabularies that can serve a variety of applications. Some examples include:
    1. providing terminology and vocabulary definitions for Documents and Publications. Define consistent terminology for general PROGRAM and Project documentation, technical reports, conference papers, guides, drawings, technical specifications, engineering and process documentation, etc.
    2. defining SOFTWARE code documentation, pragmas and/or comments, and independent reference documentation. Referencing system and software variables and constants provides explicit, unambiguous definitions that can be used for data exchanges, semantic consistency, automated checking, software reuse, and more robust search and discovery.
    3. improving the quality of SOFTWARE interfaces, web services, and data exchanges. The model basis of this standard can be used by other SOFTWARE, or to build software, for a variety of purposes; model creation, validation, compilation and run-time checking, translation and transformation, data exchange definitions, etc.
    4. generating schema specifications and data definitions in other formalisms. Examples include database, data file (ex, XML) schema, software application data structures, code-lists, and other controlled vocabularies.
    5. enabling files, datasets, messages, communications and Data Exchange Packages to use consistent terms and constructs when defining elements of datasets and messages in a variety of forms and formats.
  4. A framework designed for extensibility and evolution, but model-based (instead of just a typical dictionary) and governed.
    1. The authors recognize that any given release will not have every possible quantity, unit, dimension, or type that a user may need.
    2. The framework has been designed to grow in a consistent manner.

QUDT Ontologies and Vocabularies

The QUDT Specification is more than a list of quantities, units, dimensions, data types, enumerations, and structures. In order to provide for interoperability and data exchange between information systems, the specification needs to be available in a machine processable form, with no ambiguities.

For these reasons, the QUDT approach to specifying quantities, units, dimensions, data types, enumerations, and other data structures is to use precise semantically grounded specifications in an ontology model with translation into machine-processable representations.

Ontologies provide the object-oriented strengths of encapsulation, inheritance, and polymorphism, strengths which are unavailable in other structured modeling approaches. The characteristics modeled in QUDT require a model-based approach because they are functionally dependent.

Modeling one without modeling its dependency on the other requires that the understanding of those dependencies be carried by the observer, which injects ambiguity into the modeling approach. These models (dimensions, coordinate systems, etc.), like everything else, are hierarchical, so using a language to model them which doesn't support inheritance imposes constraints on the models and their use which, again, results in ambiguity.

QUDT semantics are based on dimensional analysis expressed in the OWL Web Ontology Language (OWL). The dimensional approach relates each unit to a system of base units using numeric factors and a vector of exponents defined over a set of fundamental dimensions. In this way, the role of each base unit in the derived unit is precisely defined. A further relationship establishes the semantics of units and quantity kinds. By this means, QUDT supports reasoning over quantities as well as units.

All QUDT models may be translated into other representations for machine processing, or other programming language structures according to need.

An overview of the ontological structure of QUDT is provided below.

Ontology Class Structure

The diagram below, exported from TopBraid Composer, illustrates the main class structure of the QUDT ontology in OWL.

QUDT-MainSystemDiagram1.jpg

Quantities, Quantity Kinds, and Quantity Values

Quantity is an observable property of an object, event or system that can be measured and quantified numerically. Quantities are differentiated by two attributes which together comprise the essential parameters needed to formalize the structure of quantities: kind andmagnitude. The kind attribute of a quantity identifies the observable property quantified, e.g. length, force, frequency; the magnitude of the quantity expresses its relative size compared to other quantities of the same kind.

For example, the speed of light in a vacuum and the escape velocity of the Earth are both quantities of the kind speed but are of different magnitudes. The speed of light in a vacuum is greater than the escape velocity of the Earth. More generally, the speed of light in a vacuum is comparable to the escape velocity of the Earth. Thus, if two quantities are of the same kind, their magnitudes can be compared and ordered. However, the same is not true if the quantities are of different kinds. There is no intrinsic way to compare the magnitude of a quantity of mass with the magnitude of a quantity of length.

Quantities may arise from definition or convention, or they may be the result of one or a series of experiments and measurements. In the first case, the quantity is exact; in the second case, measurement uncertainty cannot be discounted so the expression of a quantity's magnitude must account for the parameters of uncertainty.

Quantity Kinds

Quantity Kind is any observable property that can be measured and quantified numerically. Familiar examples include physical properties such as length, mass, time, force, energy, power, electric charge, etc. Less familiar examples include currency, interest rate, price to EARNING ratio, and information capacity.

Unit of Measure

Unit of Measure or Unit is a particular quantity of a given kind that has been chosen as a scale for measuring other quantities of the same kind. For example, the Meter is a quantity of length that has been empirically defined by the BIPM. Any quantity of length can be expressed as a number multiplied by the unit meter.

More formally, the value of a quantity Q with respect to a unit (U) is expressed as the scalar multiple of a real number (n) and U:

Q = nU

Quantity Value

A quantity value expresses the magnitude and kind of a quantity and is given by the product of a numerical value n and a unit of measure U. The number multiplying the unit is referred to as the numerical value of the quantity expressed in that unit. Refer to NIST SP 811 section 7 for more on quantity values.

Numerical Quantity Value

The numerical value of a quantity is the numerical value without the unit of measure. For example, the value of Planck's constant in Joule-Seconds (J s) is approximately 6.62606896E-34, whereas the value in Erg-Seconds (erg s) is approximately 6.62606896E-27. The numerical value of a quantity n is a mere scaling factor for the unit U. It is the product of the two, n X U, that expresses the value (magnitude and quantity kind) of the unit.

Quantity Symbol

In the same way that a unit has a symbol, a quantity also has a symbol. For example a quantity of the (quantity) kind mass usually has the symbolm. Each quantity kind has a recommended symbol associated with it. For example, t for time, Q for charge, v for velocity, T for temperature, P for power and p for pressure. A quantity usually receives a symbol that consists of the symbol of its quantity kind and an optional subscript. Symbols for quantities should be chosen ACCORDING to the international recommendations from ISO/IEC~80000, the IUPAP red book and the IUPAC green book.

The OWL model for the classes qudt:QuantityKindqudt:Quantityqudt:QuantityValuequdt:Unit is shown below.

QUDT-QuantityDiagram.jpg

Systems of Quantities and Units

The art and science of defining, standardizing, and organizing quantity kinds and units is ancient and modern. Today, scientific boards and standards bodies maintain rigorous definitions for quantity kinds and units. The definitions of quantity kinds and their relationships are derived from physical laws and mathematical transformations. Units are defined by experimental observations, by the application of physical laws, as ratios of fundamental physical constants, or by reference. One significant advance in the modern treatment of metrology has been the use of logic and mathematics to organize quantity kinds and units into systems and to analyze the relationships between them.

A system of quantity kinds is a set of one or more quantity kinds together with a set of zero or more algebraic equations that define relationships between quantity kinds in the set. In the physical sciences, the equations relating quantity kinds are typically physical laws and definitional relations, and constants of proportionality. Examples include Newton’s First Law of Motion, Coulomb’s Law, and the definition of velocity as the instantaneous change in position.

In almost all cases, the system identifies a subset of base quantity kinds. The base set is chosen so that all other quantity kinds of interest can be derived from the base quantity kinds and the algebraic equations.

A system of units is a set of units which are chosen as the reference scales for some set of quantity kinds together with the definitions of each unit. Units may be defined by experimental observation or by proportion to another unit not included in the system. If the unit system is explicitly associated with a quantity kind system, then the unit system must define at least one unit for each quantity kind.

Base and Derived Quantity Kinds

Many systems of quantity kinds identify a special subset of the included quantity kinds called the base quantity kinds. Base quantity kinds are typically chosen so that no base quantity kind can be expressed as an algebraic relation of one or more other base quantity kinds using only the constituent equations included in the system. A quantity kind that can be expressed as an algebraic relation of one or more base quantity kind is called a derived quantity kind. Thus, in any quantity kind system, the base set and derived set are disjoint.

Similarly, unit systems may distinguish between base units and derived units. A base unit is a unit of measurement for a base quantity, and a derived unit is a unit of measurement for a derived quantity. Unit systems define at least one base unit for each base quantity and at least one derived unit for each derived quantity.

Quantity Dimensions

Quantity kind systems that define base and derived sets have certain mathematical properties that permit quantity kinds to be manipulated symbolically. The construction goes as follows: Assign a distinct dimension symbol to each base quantity kind. For each derived quantity kind, take the formula that expresses it in terms of the base quantity kinds and replace every occurrence of a base quantity with its symbol. This is the dimension symbol for the derived quantity kind. In this way, every quantity kind maps to a dimension symbol of the form:

dim Q = (B1)d1(B2)d2…(Bn)dn

Here {B1,…,Bn} are the dimension symbols for the base quantities and {d1,…,dn} are rational numbers. Typically, the values of the di are between -3 and 3, however magnitudes as high as 7 are required to cover the range of quantity kinds currently defined. Using the multiplication identity for exponents AnAm = An+m one can show that the set of dimension symbols is homomorphic to an n-dimensional vector space over the rational numbers. Multiplication of quantity kinds corresponds to vector addition, division corresponds to vector subtraction, and inverting a quantity kind corresponds to COMPUTING the additive inverse of its dimension vector.

In some cases, distinct quantity kinds may have the same dimension symbol. This often occurs in cases where physical laws are discovered and formalized independently of each other, but reduce to the same base quantity kinds. A commonly quoted example is the dimensional equivalence of mechanical torque and energy. Both have the same dimensions (L2M1T-2) but are defined very differently.

One consequence of the equivalence is that the same units of measure are applicable to both. A salient difference between the two in this example is that torque is a pseudo-vector while energy is a scalar. However, this distinction (value type) is not accounted for in the quantity kind system formalism.

The OWL model of Dimensions is illustrated below.

QUDT-QuantityDimensionsDiagram.jpg

Dimensionless Quantities and Units

Dimensionless Quantities, or quantities of dimension 1, are those for which all the exponents of the factors corresponding to the base quantities in its quantity dimension are zero. Counts, ratios and plane angles are examples of dimensionless quantities.

Allowed Units

Some unit systems identify units that are not defined within the system but are allowed to be used in combination with units that are defined within the system. Allowed units must be commensurable with some defined unit of the system, so that quantities expressed in the allowed unit may be converted to a defined unit. The SI System explicitly allows a number of non-SI units.

Example Quantity Kind and Unit Systems

This section contains tables of several of the quantity kind and unit systems that are currently defined in the ontology. The table columns are:

  • Category – Either “Base᾿, “Derived᾿, or “TBD᾿

  • Quantity Kind – The name of the quantity kind

  • Quantity QName – The QName of the quantity kind

  • Dimension Symbol – The dimension symbol for the quantity kind. For derived quantity kinds, the symbol is a linear combination of the base quantity symbols, as described above.

  • Unit – The name of a unit in the unit system that is the defined unit for the quantity kind

  • Unit QName – The QName of the unit

  • Unit Symbol – A common symbol or abbreviation for the unit

The SI System

SI Base and Derived Quantities and Units

Category

Quantity Kind

QName

Dimension Symbol

Unit

QName

Unit Symbol

Base

Dimensionless

quantity:Dimensionless

U

Unity

unit:Unity My Note: Did Not Find

U

Length

qunatity:Length

L

Meter

unit:Meter

m

Mass

quantity:Mass

M

Kilogram

unit:Kilogram

kg

Time

quantity:Time

T

Second

unit:SecondTime

s

Electric Current

quantity:ElectricCurrent

I

Ampere

unit:Ampere My Note: Tested Re-Links to Here

A

Temperature

quantity:ThermodynamicTemperature

Θ

Kelvin

unit:Kelvin

K

Amount of Substance

quantity:AmountOfSubstance

N

Mole

unit:Mole

mol

Luminous Intensity

quantity:LuminousIntensity

J

Candela

unit:Candela

cd

Derived

Absorbed Dose

quantity:AbsorbedDose

L2T-2

Gray

unit:Gray

Gy

Absorbed Dose Rate

quantity:AbsorbedDoseRate

L2T-3

Gray per second

unit:GrayPerSecond

Gy/s

Activity

quantity:Activity

T-1

Becquerel

unit:Becquerel

Bq

Amount of Substance Per Unit Volume

quantity:AmountOfSubstancePerUnitVolume

L-3N1

Mole per cubic meter

unit:MolePerCubicMeter

mol/m^3

Amount of Substance per Unit Mass

quantity:AmountOfSubstancePerUnitMass 

M-3N1

Mole per kilogram

unit:MolePerKilogram

mol/kg

Angular Acceleration

quantity:AngularAcceleration

U1T-2

Radian per second squared

unit:RadianPerSecondSquared

rad/s^2

Angular Mass

quantity:AngularMass My Note: Did Not Find

L2M1

Kilogram Meter Squared

unit:KilogramMeterSquared

kg-m^2

Angular Momentum

quantity:AngularMomentum

L2M1T-1

Joule Second

unit:JouleSecond

J s

Angular Velocity

quantity:AngularVelocity

U1T-1

Radian per second

unit:RadianPerSecond

rad/s

Area

quantity:Area

L2

Square meter

unit:SquareMeter

m^2

Area Angle

quantity:AreaAngle

U1L2

Square meter steradian

unit:SquareMeterSteradian

m^2-sr

Area Temperature

quantity:AreaTemperature

L2Θ1

Square meter kelvin

unit:SquareMeterKelvin

m^2-K

Area Thermal Expansion

quantity:AreaThermalExpansion

L2Θ-1

Square meter per kelvin

unit:SquareMeterPerKelvin

m^2/K

Capacitance

quantity:Capacitance

L-2M-1T4I2

Farad

unit:Farad

F

Catalytic Activity

quantity:CatalyticActivity

T-1N1

Katal

unit:Katal

kat

Coefficient of Heat Transfer

quantity:CoefficientOfHeatTransfer

M1T-3Θ-1

Watt per square meter kelvin

unit:WattPerSquareMeterKelvin

W/(m^2-K)

Density

quantity:Density

L-3M1

Kilogram per cubic meter

unit:KilogramPerCubicMeter

kg/m^3

Dose Equivalent

quantity:DoseEquivalent

L2T-2

Sievert

unit:Sievert

Sv

Dynamic Viscosity

quantity:DynamicViscosity

L-1M1T-1

Pascal second

unit:PascalSecond

Pa-s

Electric Charge

quantity:ElectricCharge

T1I1

Coulomb

unit:Coulomb

C

Electric Charge Line Density

quantity:ElectricChargeLineDensity

L-1T1I1

Coulomb per meter

unit:CoulombPerMeter

C/m

Electric Charge Volume Density

quantity:ElectricChargeVolumeDensity

L-3T1I1

Coulomb per cubic meter

unit:CoulombPerCubicMeter

C/m^3

Electric Charge per Amount of Substance

quantity:ElectricChargePerAmountOfSubstance

T1I1N-1

Coulomb per mole

unit:CoulombPerMole

C/mol

Electric Current Density

quantity:ElectricCurrentDensity

L-2I1

Ampere per square meter

unit:AmperePerSquareMeter

A/m^2

Electric Current per Angle

quantity:CurrentPerAngle My Note: Did Not Find

U-1I1

Ampere per radian

unit:AmperePerRadian

A/rad

Electric Dipole Moment

quantity:ElectricDipoleMoment

L1T1I1

Coulomb meter

unit:CoulombMeter

C-m

Electric Field Strength

quantity:ElectricFieldStrength My Note: Did Not Find

L1M1T-3I-1

Volt per Meter

unit:VoltPerMeter

V/m

Electric Flux Density

quantity:ElectricFluxDensity My Note: Did Not Find

L-2T1I1

Coulomb per Square Meter

unit:CoulombPerSquareMeter

C/m^2

Electrical Conductivity

quantity:ElectricalConductivity My Note: Did Not Find

L-2M-1T3I2

Siemens

unit:Siemens

S

Electromotive Force

quantity:ElectromotiveForce

L2M1T-3I-1

Volt

unit:Volt

V

Energy Density

quantity:EnergyDensity

L-1M1T-2

Joule per cubic meter

unit:JoulePerCubicMeter

J/m^3

Energy and Work

quantity:EnergyAndWork

L2M1T-2

Joule

unit:Joule

J

Energy per Unit Area

quantity:EnergyPerUnitArea My Note: Did Not Find

M1T-2

Joule per square meter

unit:JoulePerSquareMeter

J/m^2

Exposure

quantity:Exposure

M-1T1I1

Coulomb per kilogram

unit:CoulombPerKilogram

C/kg

Force

quantity:Force

L1M1T-2

Newton

unit:Newton

N

Force per Electric Charge

quantity:ForcePerElectricCharge

L1M1T-3I-1

Newton per coulomb

unit:NewtonPerCoulomb

N/C

Force per Unit Length

quantity:ForcePerUnitLength My Note: Did Not Find

M1T-2

Newton per meter

unit:NewtonPerMeter

N/m

Frequency

quantity:Frequency

T-1

Hertz

unit:Hertz

Hz

Inverse second time

quantity:InverseSecondTime

s^-1

Gravitational Attraction

quantity:GravitationalAttraction

L3M-1T-2

Cubic meter per kilogram second squared

unit:CubicMeterPerKilogramSecondSquared

m^3/(kg-s^2)

Heat Capacity and Entropy

quantity:HeatCapacityAndEntropy My Note: Did Not Find

L2M1T-2Θ-1

Joule per kelvin

unit:JoulePerKelvin

J/K

Heat Flow Rate

quantity:HeatFlowRate

L2M1T-3

Watt

unit:Watt

W

Heat Flow Rate per Unit Area

quantity:HeatFlowRatePerUnitArea

M1T-3

Watt per square meter

unit:WattPerSquareMeter

W/m^2

Illuminance

quantity:Illuminance

U1L-2J1

Lux

unit:Lux

lx

Inductance

quantity:Inductance

L2M1T-2I-2

Henry

unit:Henry

H

Inverse Amount of Substance

quantity:InverseAmountOfSubstance

N-1

Per mole

unit:PerMole

mol^(-1)

Inverse Permittivity

quantity:InversePermittivity

L3M1T-4I-2

Meter per farad

unit:MeterPerFarad

m/F

Kinematic Viscosity

quantity:KinematicViscosity

L2T-1

Square meter per second

unit:SquareMeterPerSecond

m^2/sec

Length Mass

quantity:LengthMass

L1M1

Meter kilogram

unit:MeterKilogram

m-kg

Length Temperature

quantity:LengthTemperature

L1Θ1

Meter kelvin

unit:MeterKelvin

m-K

Linear Acceleration

quantity:LinearAcceleration

L1T-2

Meter per second squared

unit:MeterPerSecondSquared

m/s^2

Linear Momentum

quantity:LinearMomentum

L1M1T-1

Kilogram Meter Per Second

unit:KilogramMeterPerSecond

kg-m/s

Linear Thermal Expansion

quantity:LinearThermalExpansion

L1Θ-1

Meter per kelvin

unit:MeterPerKelvin

m/K

Linear Velocity

quantity:LinearVelocity

L1T-1

Meter per second

unit:MeterPerSecond

m/s

Luminance

quantity:Luminance

L-2J1

Candela per square meter

unit:CandelaPerSquareMeter

cd/m^2

Luminous Flux

quantity:LuminousFlux

U1J1

Lumen

unit:Lumen

lm

Magnetic Dipole Moment

quantity:MagneticDipoleMoment

L2I1

Joule per Tesla

unit:JoulePerTesla

J/T

Magnetic Field Strength

quantity:MagneticFieldStrength My Note: Did Not Find

L-1I1

Ampere Turn per Meter

unit:AmpereTurnPerMeter

At/m

Ampere per meter

quantity:AmperePerMeter

A/m

Magnetic Flux

quantity:MagneticFlux

L2M1T-2I-1

Weber

unit:Weber

Wb

Magnetic Flux Density

quantity:MagneticFluxDensity My Note: Did Not Find

M1T-2I-1

Tesla

unit:Tesla

T

Magnetomotive Force

quantity:MagnetomotiveForce

U1I1

Ampere Turn

unit:AmpereTurn

At

Mass Temperature

quantity:MassTemperature

M1Θ1

Kilogram kelvin

unit:KilogramKelvin

kg-K

Mass per Time

quantity:MassPerUnitTime My Note: Did Not Find

M1T-1

Kilogram per second

unit:KilogramPerSecond

kg/s

Mass per Unit Area

quantity:MassPerUnitArea My Note: Did Not Find

L-2M1

Kilogram per square meter

unit:KilogramPerSquareMeter

kg/m^2

Mass per Unit Length

quantity:MassPerUnitLength My Note: Did Not Find

L-1M1

Kilogram per meter

unit:KilogramPerMeter

kg/m

Molar Energy

quantity:MolarEnergy

L2M1T-2N-1

Joule per mole

unit:JoulePerMole

J/mol

Molar Heat Capacity

quantity:MolarHeatCapacity

L2M1T-2Θ-1N-1

Joule per mole kelvin

unit:JoulePerMoleKelvin

J/(mol-K)

Permeability

quantity:Permeability

L1M1T-2I-2

Henry per meter

unit:HenryPerMeter

H/m

Permittivity

quantity:Permittivity

L-3M-1T4I2

Farad per meter

unit:FaradPerMeter

F/m

Plane Angle

quantity:PlaneAngle

U1

Radian

unit:Radian

rad

Power

quantity:Power

L2M1T-3

Watt

unit:Watt

W

Power per Angle

quantity:PowerPerAngle My Note: Did Not Find

U-1L2M1T-3

Watt per steradian

unit:WattPerSteradian

W/sr

Power per Area Angle

quantity:PowerPerAreaAngle

U-1M1T-3

Watt per square meter steradian

unit:WattPerSquareMeterSteradian

W/(m^2-sr)

Power per Unit Area

quantity:PowerPerUnitArea My Note: Did Not Find

M1T-3

Watt per square meter

unit:WattPerSquareMeter

W/m^2

Pressure or Stress

quantity:PressureOrStress My Note: Did Not Find

L-1M1T-2

Pascal

unit:Pascal

Pa

Resistance

quantity:Resistance

L2M1T-3I-2

Ohm

unit:Ohm

Ohm

Solid Angle

quantity:SolidAngle

U1

Steradian

unit:Steradian

sr

Specific Energy

quantity:SpecificEnergy

L2T-2

Joule per kilogram

unit:JoulePerKilogram

J/kg

Specific Heat Capacity

quantity:SpecificHeatCapacity

L2T-2Θ-1

Joule per kilogram kelvin

unit:JoulePerKilogramKelvin

J/(kg-K)

Specific Heat Pressure

quantity:SpecificHeatPressure

L3M-1Θ-1

Joule per kilogram kelvin per pascal

unit:JoulePerKilogramKelvinPerPascal

J/(km-K-Pa)

Specific Heat Volume

quantity:SpecificHeatVolume

L-1T-2Θ-1

Joule per kilogram kelvin per cubic meter

unit:JoulePerKilogramKelvinPerCubicMeter

J/(kg-K-m^3)

Temperature Amount of Substance

quantity:TemperatureAmountOfSubstance

Θ1N1

Mole kelvin

unit:MoleKelvin

mol-K

Thermal Conductivity

quantity:ThermalConductivity

L1M1T-3Θ-1

Watt per meter kelvin

unit:WattPerMeterKelvin

W/(m*K)

Thermal Diffusivity

quantity:ThermalDiffusivity

L2T-1

Square meter per second

unit:SquareMeterPerSecond

m^2/sec

Thermal Insulance

quantity:ThermalInsulance

M-1T3Θ1

Square meter Kelvin per watt

unit:SquareMeterKelvinPerWatt

(K^2)m/W

Thermal Resistance

quantity:ThermalResistance

L-2M-1T3Θ1

Kelvin per watt

unit:KelvinPerWatt

K/W

Thermal Resistivity

quantity:ThermalResistivity

L-1M-1T3Θ1

Meter Kelvin per watt

unit:MeterKelvinPerWatt

K-m/W

Thrust to Mass Ratio

quantity:ThrustToMassRatio

L1T-2

Newton per kilogram

unit:NewtonPerKilogram

N/kg

Time Squared

quantity:TimeSquared

T2

Second time squared

unit:SecondTimeSquared

s^2

Torque

quantity:BendingMomentOrTorque My Note: Did Not Find

L2M1T-2

Newton meter

unit:NewtonMeter

N-m

Volume

quantity:Volume

L3

Cubic Meter

unit:CubicMeter

m^3

Volume Thermal Expansion

quantity:VolumeThermalExpansion

L3Θ-1

Cubic meter per kelvin

unit:CubicMeterPerKelvin

m^3/K

Volume per Unit Time

quantity:VolumePerUnitTime

L3T-1

Cubic meter per second

unit:CubicMeterPerSecond

m^3/s

Volumetric heat capacity

quantity:VolumetricHeatCapacity

L-1M1T-2Θ-1

Joule per cubic meter kelvin

unit:JoulePerCubicMeterKelvin

J/(m^3 K)


 


 

The CGS System

CGS Base and Derived Quantity Kinds and Units

Category

Quantity Kind

QName

Dimension Symbol

Unit

QName

Unit Symbol

Base

Dimensionless

quantity:Dimensionless

U

Unity

unit:Unity

U

Length

quantity:Length

L

Centimeter

unit:Centimeter

cm

Mass

quantity:Mass

M

Gram

unit:Gram

g

Time

quantity:Time

T

Second

unit:SecondTime

s

Derived

Angular Momentum

quantity:AngularMomentum

L2M1T-1

Erg second

unit:ErgSecond

erg s

Area

quantity:Area

L2

Square centimeter

unit:SquareCentimeter

cm^2

Dynamic Viscosity

quantity:DynamicViscosity

L-1M1T-1

Poise

unit:Poise

P

Energy Density

quantity:EnergyDensity

L-1M1T-2

Erg per cubic centimeter

unit:ErgPerCubicCentimeter

erg/cm^3

Energy and Work

quantity:EnergyAndWork

L2M1T-2

Erg

unit:Erg

erg

Force

quantity:Force

L1M1T-2

Dyne

unit:Dyne

dyn

Frequency

quantity:Frequency

T-1

Inverse second time

unit:InverseSecondTime

s^-1

Linear Acceleration

quantity:LinearAcceleration

L1T-2

Centimeter per second squared

unit:CentimeterPerSecondSquared

cm/s^2

Linear Velocity

quantity:LinearVelocity

L1T-1

Centimeter per second

unit:CentimeterPerSecond

cm/s

Power

quantity:Power

L2M1T-3

Erg per second

unit:ErgPerSecond

erg/s

Power per Unit Area

quantity:PowerPerUnitArea My Note: Did Not Find

M1T-3

Erg per square centimeter second

unit:ErgPerSquareCentimeterSecond

erg/(cm^2-s)

Pressure or Stress

quantity:PressureOrStress My Note: Did Not Find

L-1M1T-2

Dyne per square centimeter

unit:DynePerSquareCentimeter

dyn/cm^2

Time Area

quantity:TimeArea My Note: Did Not Find

L2T1

Square centimeter second

unit:SquareCentimeterSecond

cm^2-s

Torque

quantity:BendingMomentOrTorque My Note: Did Not Find

L2M1T-2

Dyne centimeter

unit:DyneCentimeter

dyn-cm

Volume

quantity:Volume

L3

Cubic Centimeter

unit:CubicCentimeter

cm^3


 

CGS Units for Electricity and Magnetism

There are two different approaches to defining electric and magnetic quantities using the base CGS mechanical quantities of length, mass and time. The Electromagnetic Unit (EMU) approach derives electric charge from Coulomb’s Law, while the Electrostatic Unit (ESU) approach derives electric charge from Ampere’s Law.

EMU Derived Units

Coulomb’s Law states that the force exerted between two charged particles, q1 and q2, is inversely proportional to the square of their distance, r.

F=k(q1q2)/r2

Retaining only the terms of the quantity kinds involved (force, electric charge, distance), this equation can be rearranged to express electric charge as length multiplied by the square root of force. The CGS Electromagnetic Unit is called the Abcoulomb. The table below contains the dimension symbols and corresponding units of other electricity and magnetism quantity kinds in terms of the base CGS quantity kinds and the definition of electric charge above.

CGS EMU Derived Units for Electricity and Magnetism

Quantity Kind

QName

Dimension Symbol

Unit

QName

Unit Symbol

Capacitance

quantity:Capacitance

L-1T2

Abfarad

unit:Abfarad

abF

Electric Charge

quantity:ElectricCharge

L0.5M0.5

Abcoulomb

unit:Abcoulomb

abC

Electric Current

quantity:ElectricCurrent

L0.5M0.5T-1

Abampere

unit:Abampere

abA

Electric Field Strength

quantity:ElectricFieldStrength My Note: Did Not Find

L0.5M0.5T-2

Abvolt per Centimeter

unit:AbvoltPerCentimeter

abV/cm

Electric Flux Density

quantity:ElectricFluxDensity My Note: Did Not Find

L-1.5M0.5

Abcoulomb per square centimeter

unit:AbcoulombPerSquareCentimeter

abC/cm^2

Electrical Conductivity

quantity:ElectricalConductivity My Note: Did Not Find

L-1T1

Absiemen

unit:Absiemen

aS

Electromotive Force

quantity:ElectromotiveForce

L1.5M0.5T-2

Abvolt

unit:Abvolt

abV

Inductance

quantity:Inductance

L1

Abhenry

unit:Abhenry

abH

Magnetic Field Strength

quantity:MagneticFieldStrength My Note: Did Not Find

L-0.5M0.5T-1

Abtesla

unit:Abtesla

abT

Magnetic Flux

quantity:MagneticFlux

L1.5M0.5T-1

Abvolt Second

unit:AbvoltSecond

abV-s

Magnetic Flux Density

quantity:MagneticFluxDensity My Note: Did Not Find

L-0.5M0.5T-1

Abtesla

unit:Abtesla

abT

Magnetomotive Force

quantity:MagnetomotiveForce

L0.5M0.5T-1

Gilbert

unit:Gilbert

Gi

Permeability

quantity:Permeability

U1

Relative permeability

unit:RelativePermeability

μ r

Permittivity

quantity:Permittivity

L-2T2

Abfarad per centimeter

unit:AbfaradPerCentimeter

abF/cm

Resistance

quantity:Resistance

L1T-1

Abohm

unit:Abohm

abOhm

ESU Derived Units

Ampere’s Law of Magnetic Induction states that the force per unit length exerted between two infinite parallel wires at a distince, d, and carrying electric currents I1 and I2 is proportional to their product divided by the distance between them. I.e.

dF/dl = k(I1I2/d)

Retaining only the terms of the quantity kinds involved (force, electric current, distance), this equation can be rearranged to express electric current as the square root of force. The CGS Electrostatic Unit of electric current is called the Statampere. The table below contains the dimension symbols and corresponding units of other electricity and magnetism quantity kinds in terms of the base CGS quantity kinds and the definition of electric current above.

CGS ESU Derived Units for Electricity and Magnetism

Quantity Kind

QName

Dimension Symbol

Unit

QName

Unit Symbol

Capacitance

quantity:Capacitance

L1

Statfarad

unit:Statfarad

statF

Electric Charge

quantity:ElectricCharge

L1.5M0.5T-1

Statcoulomb

unit:Statcoulomb

statC

Electric Current

quantity:ElectricCurrent

L1.5M0.5T-2

Statampere

unit:Statampere

statA

Electric Field Strength

quantity:ElectricFieldStrength My Note: Did Not Find

L-0.5M0.5T-1

Statvolt per centimeter

unit:StatvoltPerCentimeter

statV/cm

Electric Flux Density

quantity:ElectricFluxDensity My Note: Did Not Find

L-0.5M0.5T-1

Statcoulomb per square centimeter

unit:StatcoulombPerSquareCentimeter

statC/cm^2

Electromotive Force

quantity:ElectromotiveForce

L0.5M0.5T-1

Statvolt

unit:Statvolt

statV

Inductance

quantity:Inductance

L-1T2

Stathenry

unit:Stathenry

statH

Magnetic Field Strength

quantity:MagneticFieldStrength My Note: Did Not Find

L0.5M0.5T-2

Oersted

unit:Oersted

Oe

Magnetic Flux

quantity:MagneticFlux

L0.5M0.5

Maxwell

unit:Maxwell

Mx

Magnetic Flux Density

quantity:MagneticFluxDensity My Note: Did Not Find

L-1.5M0.5

Gauss

unit:Gauss

G

Magnetomotive Force

quantity:MagnetomotiveForce

L1.5M0.5T-2

Oersted centimeter

unit:OerstedCentimeter

Oe-cm

Permeability

quantity:Permeability

L-2T2

Stathenry per centimeter

unit:StathenryPerCentimeter

statH/cm

Permittivity

quantity:Permittivity

U1

Relative permittivity

unit:RelativePermittivity

ε r

Resistance

quantity:Resistance

L-1T1

Statohm

unit:Statohm

statOhm

Glossary

NExIOM
NASA Exploration Intiatives Ontology Models
TBD
To Be Done
TBR
To Be Revised

Acknowledgements

[TBR]

  1. NASA AMES Research Center for sponsoring and content for different engineering disciplines
  2. TopQuadrant, Inc., for Ontology Architecture, foundation ontologies and tooling support
  3. European Space Agency (ESA), for constructive dialog and input to the ontology models

Instances

Instances of qudt:ChemistryQuantityKind

quantity:MolecularMass: Molecular Mass

The molecular mass, or molecular weight of a chemical compound is the mass of one molecule of that compound, relative to the unified atomic mass unit, u. Molecular mass should not be confused with molar mass, which is the mass of one mole of a substance.

quantity:MolecularMass
Property Value
qudt:description The molecular mass, or molecular weight of a chemical compound is the mass of one molecule of that compound, relative to the unified atomic mass unit, u. Molecular mass should not be confused with molar mass, which is the mass of one mole of a substance.
qudt:generalization quantity:Mass
qudt:symbol M

quantity:Turbidity: Turbidity

Turbidity is the cloudiness or haziness of a fluid, or of air, caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air. Turbidity in open water is often caused by phytoplankton and the measurement of turbidity is a key test of water quality. The higher the turbidity, the higher the risk of the drinkers developing gastrointestinal diseases, especially for immune-compromised people, because contaminants like virus or bacteria can become attached to the suspended solid. The suspended solids interfere with water disinfection with chlorine because the particles act as shields for the virus and bacteria. Similarly suspended solids can protect bacteria from UV sterilisation of water. Fluids can contain suspended solid matter consisting of particles of many different sizes. While some suspended material will be large enough and heavy enough to settle rapidly to the bottom container if a liquid sample is left to stand (the settleable solids), very small particles will settle only very slowly or not at all if the sample is regularly agitated or the particles are colloidal. These small solid particles cause the liquid to appear turbid.

quantity:Turbidity
Property Value
qudt:description Turbidity is the cloudiness or haziness of a fluid, or of air, caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air. Turbidity in open water is often caused by phytoplankton and the measurement of turbidity is a key test of water quality. The higher the turbidity, the higher the risk of the drinkers developing gastrointestinal diseases, especially for immune-compromised people, because contaminants like virus or bacteria can become attached to the suspended solid. The suspended solids interfere with water disinfection with chlorine because the particles act as shields for the virus and bacteria. Similarly suspended solids can protect bacteria from UV sterilisation of water. Fluids can contain suspended solid matter consisting of particles of many different sizes. While some suspended material will be large enough and heavy enough to settle rapidly to the bottom container if a liquid sample is left to stand (the settleable solids), very small particles will settle only very slowly or not at all if the sample is regularly agitated or the particles are colloidal. These small solid particles cause the liquid to appear turbid.

Instances of qudt:ElectricityAndMagnetismQuantityKind

quantity:AuxillaryMagneticField: Auxillary Magnetic Field

Magnetic Fields surround magnetic materials and electric currents and are detected by the force they exert on other magnetic materials and moving electric charges. The electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic field. A pure electric field in one reference frame is observed as a combination of both an electric field and a magnetic field in a moving reference frame. The Auxillary Magnetic Field, H characterizes how the true Magnetic Field B influences the organization of magnetic dipoles in a given medium.

quantity:AuxillaryMagneticField
Property Value
qudt:abbreviation H
qudt:description Magnetic Fields surround magnetic materials and electric currents and are detected by the force they exert on other magnetic materials and moving electric charges. The electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic field. A pure electric field in one reference frame is observed as a combination of both an electric field and a magnetic field in a moving reference frame. The Auxillary Magnetic Field, H characterizes how the true Magnetic Field B influences the organization of magnetic dipoles in a given medium.
qudt:generalization quantity:ElectricCurrentPerUnitLength

quantity:Capacitance: Capacitance

Capacitance is the ability of a body to hold an electrical charge; it is quantified as the amount of electric charge stored for a given electric potential. Capacitance is a scalar-valued quantity.

quantity:Capacitance
Property Value
qudt:description Capacitance is the ability of a body to hold an electrical charge; it is quantified as the amount of electric charge stored for a given electric potential. Capacitance is a scalar-valued quantity.

quantity:ElectricCharge: Electric Charge

Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields. The electric charge on a body may be positive or negative. Two positively charged bodies experience a mutual repulsive force, as do two negatively charged bodies. A positively charged body and a negatively charged body experience an attractive force.

quantity:ElectricCharge
Property Value
qudt:description Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields. The electric charge on a body may be positive or negative. Two positively charged bodies experience a mutual repulsive force, as do two negatively charged bodies. A positively charged body and a negatively charged body experience an attractive force.
qudt:symbol Q

quantity:ElectricConductivity: Electric Conductivity

Electric conductivity or specific conductance is a measure of a material's ability to conduct an electric current. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity ? is defined as the ratio of the electric current density J to the electric field E: J = ?E In isotropic materials, conductivity is scalar-valued, however in general, conductivity is a tensor-valued quantity.

quantity:ElectricConductivity
Property Value
qudt:description Electric conductivity or specific conductance is a measure of a material's ability to conduct an electric current. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity ? is defined as the ratio of the electric current density J to the electric field E: J = ?E In isotropic materials, conductivity is scalar-valued, however in general, conductivity is a tensor-valued quantity.
qudt:symbol ?

quantity:ElectricCurrent: Electric Current

Electric Current is the flow (movement) of electric charge. The amount of electric current through some surface, e.g., a section through a copper conductor, is defined as the amount of electric charge flowing through that surface over time. Current is a scalar-valued quantity.

quantity:ElectricCurrent
Property Value
qudt:description Electric Current is the flow (movement) of electric charge. The amount of electric current through some surface, e.g., a section through a copper conductor, is defined as the amount of electric charge flowing through that surface over time. Current is a scalar-valued quantity.
qudt:symbol I

quantity:ElectricDipoleMoment: Electric Dipole Moment

The Electric Dipole Moment is a measure of the separation of positive and negative electrical charges in a system of (discrete or continuous) charges. It is a vector-valued quantity. If the system of charges is neutral, that is if the sum of all charges is zero, then the dipole moment of the system is independent of the choice of a reference frame; however in a non-neutral system, such as the dipole moment of a single proton, a dependence on the choice of reference point arises. In such cases it is conventional to choose the reference point to be the center of mass of the system or the center of charge, not some arbitrary origin. This convention ensures that the dipole moment is an intrinsic property of the system.

quantity:ElectricDipoleMoment
Property Value
qudt:description The Electric Dipole Moment is a measure of the separation of positive and negative electrical charges in a system of (discrete or continuous) charges. It is a vector-valued quantity. If the system of charges is neutral, that is if the sum of all charges is zero, then the dipole moment of the system is independent of the choice of a reference frame; however in a non-neutral system, such as the dipole moment of a single proton, a dependence on the choice of reference point arises. In such cases it is conventional to choose the reference point to be the center of mass of the system or the center of charge, not some arbitrary origin. This convention ensures that the dipole moment is an intrinsic property of the system.

quantity:ElectricField: Electric Field

The space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. This electric field exerts a force on other electrically charged objects. In the idealized case, the force exerted between two point charges is inversely proportional to the square of the distance between them. (Coulomb's Law)

quantity:ElectricField
Property Value
qudt:abbreviation E
qudt:description The space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. This electric field exerts a force on other electrically charged objects. In the idealized case, the force exerted between two point charges is inversely proportional to the square of the distance between them. (Coulomb's Law)

quantity:ElectricFlux: Electric Flux

The Electric Flux through an area is defined as the electric field multiplied by the area of the surface projected in a plane perpendicular to the field. Electric Flux is a scalar-valued quantity.

quantity:ElectricFlux
Property Value
qudt:description The Electric Flux through an area is defined as the electric field multiplied by the area of the surface projected in a plane perpendicular to the field. Electric Flux is a scalar-valued quantity.

quantity:ElectricPotential: Electric Potential

The Electric Potential is a scalar valued quantity associated with an electric field. The electric potential ?(x) at a point, x, is formally defined as the line integral of the electric field taken along a path from x to the point at infinity. If the electric field is static, i.e. time independent, then the choice of the path is arbitrary; however if the electric field is time dependent, taking the integral along different paths will produce different results.

quantity:ElectricPotential
Property Value
qudt:description The Electric Potential is a scalar valued quantity associated with an electric field. The electric potential ?(x) at a point, x, is formally defined as the line integral of the electric field taken along a path from x to the point at infinity. If the electric field is static, i.e. time independent, then the choice of the path is arbitrary; however if the electric field is time dependent, taking the integral along different paths will produce different results.
qudt:generalization quantity:EnergyPerElectricCharge
qudt:symbol ?

quantity:ElectricPower: Electric Power

Electric power is the rate at which electrical energy is transferred by an electric circuit. In the simple case of direct current circuits, electric power can be calculated as the product of the potential difference in the circuit (V) and the amount of current flowing in the circuit (I): P = VI where P is the power V is the potential difference I is the current. However, in general electric power is calculated by taking the integral of the vector cross-product of the electrical and magnetic fields over a specified area.

quantity:ElectricPower
Property Value
qudt:description Electric power is the rate at which electrical energy is transferred by an electric circuit. In the simple case of direct current circuits, electric power can be calculated as the product of the potential difference in the circuit (V) and the amount of current flowing in the circuit (I): P = VI where P is the power V is the potential difference I is the current. However, in general electric power is calculated by taking the integral of the vector cross-product of the electrical and magnetic fields over a specified area.
qudt:generalization quantity:Power

quantity:ElectricQuadrupoleMoment: Electric Quadrupole Moment

The Electric Quadrupole Moment is a quantity which describes the effective shape of the ellipsoid of nuclear charge distribution. A non-zero quadrupole moment Q indicates that the charge distribution is not spherically symmetric. By convention, the value of Q is taken to be positive if the ellipsoid is prolate and negative if it is oblate. In general, the electric quadrupole moment is tensor-valued.

quantity:ElectricQuadrupoleMoment
Property Value
qudt:description The Electric Quadrupole Moment is a quantity which describes the effective shape of the ellipsoid of nuclear charge distribution. A non-zero quadrupole moment Q indicates that the charge distribution is not spherically symmetric. By convention, the value of Q is taken to be positive if the ellipsoid is prolate and negative if it is oblate. In general, the electric quadrupole moment is tensor-valued.
qudt:symbol Q

quantity:Inductance: Inductance

Inductance is an electromagentic quantity that characterizes a circuit's resistance to any change of electric current; a change in the electric current through induces an opposing electromotive force (EMF). Quantitatively, inductance is proportional to the magnetic flux per unit of electric current.

quantity:Inductance
Property Value
qudt:description Inductance is an electromagentic quantity that characterizes a circuit's resistance to any change of electric current; a change in the electric current through induces an opposing electromotive force (EMF). Quantitatively, inductance is proportional to the magnetic flux per unit of electric current.
qudt:symbol L

quantity:MagneticDipoleMoment: Magnetic Dipole Moment

The magnetic moment of a system is a measure of the magnitude and the direction of its magnetism. Magnetic moment usually refers to its Magnetic Dipole Moment, and quantifies the contribution of the system's internal magnetism to the external dipolar magnetic field produced by the system (that is, the component of the external magnetic field that is inversely proportional to the cube of the distance to the observer). The Magnetic Dipole Moment is a vector-valued quantity.

quantity:MagneticDipoleMoment
Property Value
qudt:description The magnetic moment of a system is a measure of the magnitude and the direction of its magnetism. Magnetic moment usually refers to its Magnetic Dipole Moment, and quantifies the contribution of the system's internal magnetism to the external dipolar magnetic field produced by the system (that is, the component of the external magnetic field that is inversely proportional to the cube of the distance to the observer). The Magnetic Dipole Moment is a vector-valued quantity.
qudt:symbol ?

quantity:MagneticField: Magnetic Field

The Magnetic Field, denoted B, is a fundamental field in electrodynamics which characterizes the magnetic force exerted by electric currents. It is closely related to the auxillary magnetic field H (see quantity:AuxillaryMagneticField).

quantity:MagneticField
Property Value
qudt:abbreviation B
qudt:description The Magnetic Field, denoted B, is a fundamental field in electrodynamics which characterizes the magnetic force exerted by electric currents. It is closely related to the auxillary magnetic field H (see quantity:AuxillaryMagneticField).
qudt:symbol B

quantity:MagnetomotiveForce: Magnetomotive Force

Magnetomotive Force (mmf) is the ability of an electric circuit to produce magnetic flux. Just as the ability of a battery to produce electric current is called its electromotive force or emf, mmf is taken as the work required to move a unit magnet pole from any point through any path which links the electric circuit back the same point in the presence of the magnetic force produced by the electric current in the circuit.

quantity:MagnetomotiveForce
Property Value
qudt:description Magnetomotive Force (mmf) is the ability of an electric circuit to produce magnetic flux. Just as the ability of a battery to produce electric current is called its electromotive force or emf, mmf is taken as the work required to move a unit magnet pole from any point through any path which links the electric circuit back the same point in the presence of the magnetic force produced by the electric current in the circuit.

quantity:Permeability: Permeability

Permeability is the degree of magnetization of a material that responds linearly to an applied magnetic field. In general permeability is a tensor-valued quantity.

quantity:Permeability
Property Value
qudt:description Permeability is the degree of magnetization of a material that responds linearly to an applied magnetic field. In general permeability is a tensor-valued quantity.
qudt:symbol ?

quantity:Permittivity: Permittivity

Permittivity is a physical quantity that describes how an electric field affects, and is affected by a dielectric medium, and is determined by the ability of a material to polarize in response to the field, and thereby reduce the total electric field inside the material. Permittivity is often a scalar valued quantity, however in the general case it is tensor-valued.

quantity:Permittivity
Property Value
qudt:description Permittivity is a physical quantity that describes how an electric field affects, and is affected by a dielectric medium, and is determined by the ability of a material to polarize in response to the field, and thereby reduce the total electric field inside the material. Permittivity is often a scalar valued quantity, however in the general case it is tensor-valued.
qudt:symbol ?

quantity:Polarizability: Polarizability

Polarizability is the relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, which may be caused by the presence of a nearby ion or dipole. The electronic polarizability ? is defined as the ratio of the induced dipole moment of an atom to the electric field that produces this dipole moment. Polarizability is often a scalar valued quantity, however in the general case it is tensor-valued.

quantity:Polarizability
Property Value
qudt:description Polarizability is the relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, which may be caused by the presence of a nearby ion or dipole. The electronic polarizability ? is defined as the ratio of the induced dipole moment of an atom to the electric field that produces this dipole moment. Polarizability is often a scalar valued quantity, however in the general case it is tensor-valued.
qudt:symbol ?

Instances of qudt:FluidMechanicsQuantityKind

quantity:AtmosphericPressure: Atmospheric Pressure

The pressure exerted at a point due to the presence of an atmosphere. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location. Similarly, as elevation increases there is less overlying atmospheric mass, so that pressure decreases with increasing elevation. [Wikipedia]

quantity:AtmosphericPressure
Property Value
qudt:description The pressure exerted at a point due to the presence of an atmosphere. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location. Similarly, as elevation increases there is less overlying atmospheric mass, so that pressure decreases with increasing elevation. [Wikipedia]
qudt:generalization quantity:Pressure

quantity:DynamicPressure: Dynamic Pressure

Dynamic Pressure (indicated with q, or Q, and sometimes called velocity pressure) is the quantity defined by: q = 1/2 * ?v^2 where (using SI units): q = dynamic pressure in pascals ? = fluid density in kg/m3 (e.g. density of air) v = fluid velocity in m/s

quantity:DynamicPressure
Property Value
qudt:description Dynamic Pressure (indicated with q, or Q, and sometimes called velocity pressure) is the quantity defined by: q = 1/2 * ?v^2 where (using SI units): q = dynamic pressure in pascals ? = fluid density in kg/m3 (e.g. density of air) v = fluid velocity in m/s
qudt:generalization quantity:Pressure
qudt:symbol q

quantity:KinematicViscosity: Kinematic Viscosity

quantity:KinematicViscosity
Property Value
qudt:abbreviation The Kinematic Viscosity of a fluid is the dynamic viscosity divided by the fluid density.
qudt:generalization quantity:AreaPerTime

quantity:Pressure: Pressure

Pressure is an effect which occurs when a force is applied on a surface. Pressure is the amount of force acting on a unit area. Pressure is distinct from stress, as the former is the ratio of the component of force normal to a surface to the surface area. Stress is a tensor that relates the vector force to the vector area.

quantity:Pressure
Property Value
qudt:description Pressure is an effect which occurs when a force is applied on a surface. Pressure is the amount of force acting on a unit area. Pressure is distinct from stress, as the former is the ratio of the component of force normal to a surface to the surface area. Stress is a tensor that relates the vector force to the vector area.
qudt:generalization quantity:ForcePerArea

quantity:StaticPressure: Static Pressure

Static Pressure is the pressure at a nominated point in a fluid. Every point in a steadily flowing fluid, regardless of the fluid speed at that point, has its own static pressure P, dynamic pressure q, and total pressure P_0. The total pressure is the sum of the dynamic and static pressures, i.e. P_0 = P + q.

quantity:StaticPressure
Property Value
qudt:description Static Pressure is the pressure at a nominated point in a fluid. Every point in a steadily flowing fluid, regardless of the fluid speed at that point, has its own static pressure P, dynamic pressure q, and total pressure P_0. The total pressure is the sum of the dynamic and static pressures, i.e. P_0 = P + q.
qudt:generalization quantity:Pressure

quantity:Viscosity: Viscosity

Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In general terms it is the resistance of a liquid to flow, or its "thickness". Viscosity describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction. [Wikipedia]

quantity:Viscosity
Property Value
qudt:description Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In general terms it is the resistance of a liquid to flow, or its "thickness". Viscosity describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction. [Wikipedia]

quantity:Vorticity: Vorticity

In the simplest sense, vorticity is the tendency for elements of a fluid to "spin." More formally, vorticity can be related to the amount of "circulation" or "rotation" (or more strictly, the local angular rate of rotation) in a fluid. The average vorticity in a small region of fluid flow is equal to the circulation C around the boundary of the small region, divided by the area A of the small region. Mathematically, vorticity is a vector field and is defined as the curl of the velocity field.

quantity:Vorticity
Property Value
qudt:description In the simplest sense, vorticity is the tendency for elements of a fluid to "spin." More formally, vorticity can be related to the amount of "circulation" or "rotation" (or more strictly, the local angular rate of rotation) in a fluid. The average vorticity in a small region of fluid flow is equal to the circulation C around the boundary of the small region, divided by the area A of the small region. Mathematically, vorticity is a vector field and is defined as the curl of the velocity field.
qudt:generalization quantity:AngularVelocity
qudt:symbol ?

Instances of qudt:InformationQuantityKind

quantity:Capacity: Capacity

In computer operations, (a) the largest quantity which can be stored, processed, or transferred; (b) the largest number of digits or characters which may regularly be processed; (c) the upper and lower limits of the quantities which may be processed. In other contexts, the amount of material that can be stored, such as fuel or food.

quantity:Capacity
Property Value
qudt:description In computer operations, (a) the largest quantity which can be stored, processed, or transferred; (b) the largest number of digits or characters which may regularly be processed; (c) the upper and lower limits of the quantities which may be processed. In other contexts, the amount of material that can be stored, such as fuel or food.
qudt:symbol TBD

quantity:DataRate: Data Rate

The frequency derived from the period of time required to transmit one bit. This represents the amount of data transferred per second by a communications channel or a computing or storage device. Data rate is measured in units of bits per second (written "b/s" or "bps"), bytes per second (Bps), or baud. When applied to data rate, the multiplier prefixes "kilo-", "mega-", "giga-", etc. (and their abbreviations, "k", "M", "G", etc.) always denote powers of 1000. For example, 64 kbps is 64,000 bits per second. This contrasts with units of storage which use different prefixes to denote multiplication by powers of 1024, e.g. 1 kibibit = 1024 bits.

quantity:DataRate
Property Value
qudt:description The frequency derived from the period of time required to transmit one bit. This represents the amount of data transferred per second by a communications channel or a computing or storage device. Data rate is measured in units of bits per second (written "b/s" or "bps"), bytes per second (Bps), or baud. When applied to data rate, the multiplier prefixes "kilo-", "mega-", "giga-", etc. (and their abbreviations, "k", "M", "G", etc.) always denote powers of 1000. For example, 64 kbps is 64,000 bits per second. This contrasts with units of storage which use different prefixes to denote multiplication by powers of 1024, e.g. 1 kibibit = 1024 bits.

Instances of qudt:MechanicsQuantityKind

quantity:AngularMomentum: Angular Momentum

Quantity of rotational motion. Linear momentum is the quantity obtained by multiplying the mass of a body by its linear velocity. Angular momentum is the quantity obtained by multiplying the moment of inertia of a body by its angular velocity. The momentum of a system of particles is given by the sum of the momenta of the individual particles which make up the system or by the product of the total mass of the system and the velocity of the center of gravity of the system. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium. In physics, the angular momentum of an object rotating about some reference point is the measure of the extent to which the object will continue to rotate about that point unless acted upon by an external torque. In particular, if a point mass rotates about an axis, then the angular momentum with respect to a point on the axis is related to the mass of the object, the velocity and the distance of the mass to the axis. While the motion associated with linear momentum has no absolute frame of reference, the rotation associated with angular momentum is sometimes spoken of as being measured relative to the fixed stars.

quantity:AngularMomentum
Property Value
qudt:description Quantity of rotational motion. Linear momentum is the quantity obtained by multiplying the mass of a body by its linear velocity. Angular momentum is the quantity obtained by multiplying the moment of inertia of a body by its angular velocity. The momentum of a system of particles is given by the sum of the momenta of the individual particles which make up the system or by the product of the total mass of the system and the velocity of the center of gravity of the system. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium. In physics, the angular momentum of an object rotating about some reference point is the measure of the extent to which the object will continue to rotate about that point unless acted upon by an external torque. In particular, if a point mass rotates about an axis, then the angular momentum with respect to a point on the axis is related to the mass of the object, the velocity and the distance of the mass to the axis. While the motion associated with linear momentum has no absolute frame of reference, the rotation associated with angular momentum is sometimes spoken of as being measured relative to the fixed stars.
qudt:generalization quantity:Momentum

quantity:Force: Force

Force is an influence that causes mass to accelerate. It may be experienced as a lift, a push, or a pull. Force is defined by Newton's Second Law as F = m · a, where F is force, m is mass and a is acceleration. Net force is mathematically equal to the time rate of change of the momentum of the body on which it acts. Since momentum is a vector quantity (has both a magnitude and direction), force also is a vector quantity.

quantity:Force
Property Value
qudt:description Force is an influence that causes mass to accelerate. It may be experienced as a lift, a push, or a pull. Force is defined by Newton's Second Law as F = m · a, where F is force, m is mass and a is acceleration. Net force is mathematically equal to the time rate of change of the momentum of the body on which it acts. Since momentum is a vector quantity (has both a magnitude and direction), force also is a vector quantity.

quantity:Friction: Friction

Friction is the force of two surfaces In contact, or the force of a medium acting on a moving object (i.e. air on an aircraft). When contacting surfaces move relative to each other, the friction between the two objects converts kinetic energy into thermal energy.

quantity:Friction
Property Value
qudt:description Friction is the force of two surfaces In contact, or the force of a medium acting on a moving object (i.e. air on an aircraft). When contacting surfaces move relative to each other, the friction between the two objects converts kinetic energy into thermal energy.
qudt:generalization quantity:Force

quantity:KineticEnergy: Kinetic Energy

The energy which a body possesses as a consequence of its motion, defined as one-half the product of its mass m and the square of its speed v, 1/2 mv^2. The kinetic energy per unit volume of a fluid parcel is the 1/2 p v2 , where p is the density and v the speed of the parcel. See potential energy. For relativistic speeds the kinetic energy is given by Ek = mc^2 - m0c^2 where c is the velocity of light in a vacuum, m0 is the rest mass, and m is the moving mass.

quantity:KineticEnergy
Property Value
qudt:description The energy which a body possesses as a consequence of its motion, defined as one-half the product of its mass m and the square of its speed v, 1/2 mv^2. The kinetic energy per unit volume of a fluid parcel is the 1/2 p v2 , where p is the density and v the speed of the parcel. See potential energy. For relativistic speeds the kinetic energy is given by Ek = mc^2 - m0c^2 where c is the velocity of light in a vacuum, m0 is the rest mass, and m is the moving mass.
qudt:generalization quantity:EnergyAndWork

quantity:Momentum: Momentum

Quantity of motion. Linear momentum is the quantity obtained by multiplying the mass of a body by its linear speed. Angular momentum is the quantity obtained by multiplying the moment of inertia of a body by its angular speed. The momentum of a system of particles is given by the sum of the momentums of the individual particles which make up the system or by the product of the total mass of the system and the velocity of the center of gravity of the system. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium.

quantity:Momentum
Property Value
qudt:description Quantity of motion. Linear momentum is the quantity obtained by multiplying the mass of a body by its linear speed. Angular momentum is the quantity obtained by multiplying the moment of inertia of a body by its angular speed. The momentum of a system of particles is given by the sum of the momentums of the individual particles which make up the system or by the product of the total mass of the system and the velocity of the center of gravity of the system. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium.

quantity:PolarMomentOfInertia: Polar moment of inertia

The polar moment of inertia is a quantity used to predict an object's ability to resist torsion, in objects (or segments of objects) with an invariant circular cross-section and no significant warping or out-of-plane deformation. It is used to calculate the angular displacement of an object subjected to a torque. It is analogous to the area moment of inertia, which characterizes an object's ability to resist bending.

quantity:PolarMomentOfInertia
Property Value
qudt:description The polar moment of inertia is a quantity used to predict an object's ability to resist torsion, in objects (or segments of objects) with an invariant circular cross-section and no significant warping or out-of-plane deformation. It is used to calculate the angular displacement of an object subjected to a torque. It is analogous to the area moment of inertia, which characterizes an object's ability to resist bending.

quantity:Power: Power

Power is the rate at which work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time. As a rate of change of work done or the energy of a subsystem, power is: P = W/t where P is power W is work t is time. [Wikipedia]

quantity:Power
Property Value
qudt:description Power is the rate at which work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time. As a rate of change of work done or the energy of a subsystem, power is: P = W/t where P is power W is work t is time. [Wikipedia]

quantity:Thrust: Thrust

Thrust is a reaction force described quantitatively by Newton's Second and Third Laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system. 1. The pushing or pulling force developed by an aircraft engine or a rocket engine. 2. The force exerted in any direction by a fluid jet or by a powered screw, as, the thrust of an antitorque rotor. 3. (symbol F). Specifically, in rocketry, F = mv where m is propellant mass flow and v is exhaust velocity relative to the vehicle. Also called momentum thrust.

quantity:Thrust
Property Value
qudt:description Thrust is a reaction force described quantitatively by Newton's Second and Third Laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system. 1. The pushing or pulling force developed by an aircraft engine or a rocket engine. 2. The force exerted in any direction by a fluid jet or by a powered screw, as, the thrust of an antitorque rotor. 3. (symbol F). Specifically, in rocketry, F = mv where m is propellant mass flow and v is exhaust velocity relative to the vehicle. Also called momentum thrust.
qudt:generalization quantity:Force

quantity:Torque: Torque

In physics, a torque (?) is a vector that measures the tendency of a force to rotate an object about some axis [1]. The magnitude of a torque is defined as force times its lever arm [2]. Just as a force is a push or a pull, a torque can be thought of as a twist. The SI unit for torque is newton meters (N m). In U.S. customary units, it is measured in foot pounds (ft lbf) (also known as 'pounds feet'). Mathematically, the torque on a particle (which has the position r in some reference frame) can be defined as the cross product: ? = r x F where r is the particle's position vector relative to the fulcrum F is the force acting on the particles, or, more generally, torque can be defined as the rate of change of angular momentum, ? = dL/dt where L is the angular momentum vector t stands for time. [Wikipedia]

quantity:Torque
Property Value
qudt:description In physics, a torque (?) is a vector that measures the tendency of a force to rotate an object about some axis [1]. The magnitude of a torque is defined as force times its lever arm [2]. Just as a force is a push or a pull, a torque can be thought of as a twist. The SI unit for torque is newton meters (N m). In U.S. customary units, it is measured in foot pounds (ft lbf) (also known as 'pounds feet'). Mathematically, the torque on a particle (which has the position r in some reference frame) can be defined as the cross product: ? = r x F where r is the particle's position vector relative to the fulcrum F is the force acting on the particles, or, more generally, torque can be defined as the rate of change of angular momentum, ? = dL/dt where L is the angular momentum vector t stands for time. [Wikipedia]

quantity:Weight: Weight

1. The force with which a body is attracted toward an astronomical body. 2. The product of the mass of a body and the acceleration acting on a body. In a dynamic situation, the weight can be a multiple of that under resting conditions. Weight also varies on other planets in accordance with their gravity.

quantity:Weight
Property Value
qudt:description 1. The force with which a body is attracted toward an astronomical body. 2. The product of the mass of a body and the acceleration acting on a body. In a dynamic situation, the weight can be a multiple of that under resting conditions. Weight also varies on other planets in accordance with their gravity.

Instances of qudt:PhotometryQuantityKind

quantity:Luminance: Luminance

Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.

quantity:Luminance
Property Value
qudt:description Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.

quantity:LuminousEfficacy: Luminous Efficacy

Luminous Efficacy is the ratio of luminous flux (in lumens) to power (usually measured in watts). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source.

quantity:LuminousEfficacy
Property Value
qudt:description Luminous Efficacy is the ratio of luminous flux (in lumens) to power (usually measured in watts). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source.

quantity:LuminousFlux: Luminous Flux

Luminous Flux or Luminous Power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.

quantity:LuminousFlux
Property Value
qudt:description Luminous Flux or Luminous Power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.
qudt:symbol F

quantity:LuminousIntensity: Luminous Intensity

Luminous Intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit solid angle. The weighting is determined by the luminosity function, a standardized model of the sensitivity of the human eye to different wavelengths.

quantity:LuminousIntensity
Property Value
qudt:description Luminous Intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit solid angle. The weighting is determined by the luminosity function, a standardized model of the sensitivity of the human eye to different wavelengths.
qudt:symbol J

Instances of qudt:QuantityKind

quantity:Gain: Gain

A general term used to denote an increase in signal power or signal strength in transmission from one point to another. Gain is usually expressed in decibels and is widely used to denote transducer gain. An increase or amplification. In radar there are two general usages of the term: (a) antenna gain, or gain factor, is the ratio of the power transmitted along the beam axis to that of an isotropic radiator transmitting the same total power; (b) receiver gain, or video gain, is the amplification given a signal by the receiver.

quantity:Gain
Property Value
qudt:description A general term used to denote an increase in signal power or signal strength in transmission from one point to another. Gain is usually expressed in decibels and is widely used to denote transducer gain. An increase or amplification. In radar there are two general usages of the term: (a) antenna gain, or gain factor, is the ratio of the power transmitted along the beam axis to that of an isotropic radiator transmitting the same total power; (b) receiver gain, or video gain, is the amplification given a signal by the receiver.
qudt:generalization quantity:DimensionlessRatio

Instances of qudt:RadiologyQuantityKind

quantity:AbsorbedDose: Absorbed Dose

Absorbed dose (also known as Total Ionizing Dose, TID) is a measure of the energy deposited in a medium by ionizing radiation. It is equal to the energy deposited per unit mass of medium, and so has the unit J/kg, which is given the special name Gray (Gy). Note that the absorbed dose is not a good indicator of the likely biological effect. 1 Gy of alpha radiation would be much more biologically damaging than 1 Gy of photon radiation for example. Appropriate weighting factors can be applied reflecting the different relative biological effects to find the equivalent dose. The risk of stoctic effects due to radiation exposure can be quantified using the effective dose, which is a weighted average of the equivalent dose to each organ depending upon its radiosensitivity. When ionising radiation is used to treat cancer, the doctor will usually prescribe the radiotherapy treatment in Gy. When risk from ionising radiation is being discussed, a related unit, the Sievert is used.

quantity:AbsorbedDose
Property Value
qudt:description Absorbed dose (also known as Total Ionizing Dose, TID) is a measure of the energy deposited in a medium by ionizing radiation. It is equal to the energy deposited per unit mass of medium, and so has the unit J/kg, which is given the special name Gray (Gy). Note that the absorbed dose is not a good indicator of the likely biological effect. 1 Gy of alpha radiation would be much more biologically damaging than 1 Gy of photon radiation for example. Appropriate weighting factors can be applied reflecting the different relative biological effects to find the equivalent dose. The risk of stoctic effects due to radiation exposure can be quantified using the effective dose, which is a weighted average of the equivalent dose to each organ depending upon its radiosensitivity. When ionising radiation is used to treat cancer, the doctor will usually prescribe the radiotherapy treatment in Gy. When risk from ionising radiation is being discussed, a related unit, the Sievert is used.
qudt:generalization quantity:SpecificEnergy

quantity:DoseEquivalent: Dose Equivalent

The equivalent dose to a tissue is found by multiplying the absorbed dose, in gray, by a dimensionless "quality factor" Q, dependent upon radiation type, and by another dimensionless factor N, dependent on all other pertinent factors. N depends upon the part of the body irradiated, the time and volume over which the dose was spread, even the species of the subject.

quantity:DoseEquivalent
Property Value
qudt:description The equivalent dose to a tissue is found by multiplying the absorbed dose, in gray, by a dimensionless "quality factor" Q, dependent upon radiation type, and by another dimensionless factor N, dependent on all other pertinent factors. N depends upon the part of the body irradiated, the time and volume over which the dose was spread, even the species of the subject.
qudt:generalization quantity:SpecificEnergy

Instances of qudt:RadiometryQuantityKind

quantity:Irradiance: Irradiance

Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.

quantity:Irradiance
Property Value
qudt:description Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.
qudt:generalization quantity:PowerPerArea

quantity:RadiantEmmitance: Radiant Emmitance

Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.

quantity:RadiantEmmitance
Property Value
qudt:description Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.
qudt:generalization quantity:PowerPerArea

quantity:RadiantFlux: Radiant Flux

Radiant Flux, or radiant power, is the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light). The power may be the total emitted from a source, or the total landing on a particular surface.

quantity:RadiantFlux
Property Value
qudt:description Radiant Flux, or radiant power, is the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light). The power may be the total emitted from a source, or the total landing on a particular surface.
qudt:generalization quantity:Power
qudt:symbol ?

quantity:SecondMomentOfArea: Second Moment of Area

The second moment of area is a property of a physical object that can be used to predict its resistance to bending and deflection. The deflection of an object under load depends not only on the load, but also on the geometry of the object's cross-section.

quantity:SecondMomentOfArea
Property Value
qudt:description The second moment of area is a property of a physical object that can be used to predict its resistance to bending and deflection. The deflection of an object under load depends not only on the load, but also on the geometry of the object's cross-section.

quantity:Strain: Strain

In any branch of science dealing with materials and their behaviour, strain is the geometrical expression of deformation caused by the action of stress on a physical body. Strain is calculated by first assuming a change between two body states: the beginning state and the final state. Then the difference in placement of two points in this body in those two states expresses the numerical value of strain. Strain therefore expresses itself as a change in size and/or shape. [Wikipedia]

quantity:Strain
Property Value
qudt:description In any branch of science dealing with materials and their behaviour, strain is the geometrical expression of deformation caused by the action of stress on a physical body. Strain is calculated by first assuming a change between two body states: the beginning state and the final state. Then the difference in placement of two points in this body in those two states expresses the numerical value of strain. Strain therefore expresses itself as a change in size and/or shape. [Wikipedia]
qudt:generalization quantity:Dimensionless

quantity:Stress: Stress

Stress is a measure of the average amount of force exerted per unit area of a surface within a deformable body on which internal forces act. In other words, it is a measure of the intensity or internal distribution of the total internal forces acting within a deformable body across imaginary surfaces. These internal forces are produced between the particles in the body as a reaction to external forces applied on the body.

quantity:Stress
Property Value
qudt:description Stress is a measure of the average amount of force exerted per unit area of a surface within a deformable body on which internal forces act. In other words, it is a measure of the intensity or internal distribution of the total internal forces acting within a deformable body across imaginary surfaces. These internal forces are produced between the particles in the body as a reaction to external forces applied on the body.
qudt:generalization quantity:ForcePerArea

Instances of qudt:SpaceAndTimeQuantityKind

quantity:Acceleration: Acceleration

Acceleration is the (instantaneous) rate of change of velocity. Acceleration may be either linear acceleration, or angular acceleration. It is a vector quantity with dimension length/time^2 for linear acceleration, or in the case of angular acceleration, with dimension angle/time^2. In SI units, linear acceleration is measured in meters/second^2 (m·s^-2) and angular acceleration is measured in radians/second^2. In common speech, the term acceleration is only used for an increase in speed. In physics, any increase or decrease in speed is referred to as acceleration and similarly, motion in a circle at constant speed is also an acceleration, since the direction component of the velocity is changing.

quantity:Acceleration
Property Value
qudt:description Acceleration is the (instantaneous) rate of change of velocity. Acceleration may be either linear acceleration, or angular acceleration. It is a vector quantity with dimension length/time^2 for linear acceleration, or in the case of angular acceleration, with dimension angle/time^2. In SI units, linear acceleration is measured in meters/second^2 (m·s^-2) and angular acceleration is measured in radians/second^2. In common speech, the term acceleration is only used for an increase in speed. In physics, any increase or decrease in speed is referred to as acceleration and similarly, motion in a circle at constant speed is also an acceleration, since the direction component of the velocity is changing.

quantity:Angle: Angle

The inclination to each other of two intersecting lines, measured by the arc of a circle intercepted between the two lines forming the angle, the center of the circle being the point of intersection. An acute angle is less than 90°; a right angle 90 °; an obtuse angle, more than 90° but less than 180 °; a straight angle, 180°; a reflex angle, more than 180° but less than 360°; a perigon, 360°. Any angle not a multiple of 90° is an oblique angle. If the sum of two angles is 90°, they are complementary angles; if 180°, supplementary angles; if 360°, explementary angles. Two adjacent angles have a common vertex and lie on opposite sides of a common side. A dihedral angle is the angle between two intersecting planes. A spherical angle is the angle between two intersecting great circles.

quantity:Angle
Property Value
qudt:description The inclination to each other of two intersecting lines, measured by the arc of a circle intercepted between the two lines forming the angle, the center of the circle being the point of intersection. An acute angle is less than 90°; a right angle 90 °; an obtuse angle, more than 90° but less than 180 °; a straight angle, 180°; a reflex angle, more than 180° but less than 360°; a perigon, 360°. Any angle not a multiple of 90° is an oblique angle. If the sum of two angles is 90°, they are complementary angles; if 180°, supplementary angles; if 360°, explementary angles. Two adjacent angles have a common vertex and lie on opposite sides of a common side. A dihedral angle is the angle between two intersecting planes. A spherical angle is the angle between two intersecting great circles.
qudt:generalization quantity:DimensionlessRatio

quantity:AngularAcceleration: Angular Acceleration

Angular acceleration is the rate of change of angular velocity over time. Measurement of the change made in the rate of change of an angle that a spinning object undergoes per unit time. It is a vector quantity. Also called Rotational acceleration. In SI units, it is measured in radians per second squared (rad/s^2), and is usually denoted by the Greek letter alpha.

quantity:AngularAcceleration
Property Value
qudt:description Angular acceleration is the rate of change of angular velocity over time. Measurement of the change made in the rate of change of an angle that a spinning object undergoes per unit time. It is a vector quantity. Also called Rotational acceleration. In SI units, it is measured in radians per second squared (rad/s^2), and is usually denoted by the Greek letter alpha.
qudt:generalization quantity:Acceleration

quantity:Area: Area

Area is a quantity expressing the two-dimensional size of a defined part of a surface, typically a region bounded by a closed curve.

quantity:Area
Property Value
qudt:description Area is a quantity expressing the two-dimensional size of a defined part of a surface, typically a region bounded by a closed curve.

quantity:Curvature: Curvature

The canonical example of extrinsic curvature is that of a circle, which has curvature equal to the inverse of its radius everywhere. Smaller circles bend more sharply, and hence have higher curvature. The curvature of a smooth curve is defined as the curvature of its osculating circle at each point. The osculating circle of a sufficiently smooth plane curve at a given point on the curve is the circle whose center lies on the inner normal line and whose curvature is the same as that of the given curve at that point. This circle is tangent to the curve at the given point. That is, given a point P on a smooth curve C, the curvature of C at P is defined to be 1/R where R is the radius of the osculating circle of C at P. The magnitude of curvature at points on physical curves can be measured in diopters (also spelled dioptre) — this is the convention in optics. [Wikipedia]

quantity:Curvature
Property Value
qudt:description The canonical example of extrinsic curvature is that of a circle, which has curvature equal to the inverse of its radius everywhere. Smaller circles bend more sharply, and hence have higher curvature. The curvature of a smooth curve is defined as the curvature of its osculating circle at each point. The osculating circle of a sufficiently smooth plane curve at a given point on the curve is the circle whose center lies on the inner normal line and whose curvature is the same as that of the given curve at that point. This circle is tangent to the curve at the given point. That is, given a point P on a smooth curve C, the curvature of C at P is defined to be 1/R where R is the radius of the osculating circle of C at P. The magnitude of curvature at points on physical curves can be measured in diopters (also spelled dioptre) — this is the convention in optics. [Wikipedia]

quantity:Frequency: Frequency

Frequency is the number of occurrences of a repeatiing event per unit time. The repetition of the events may be periodic (i.e. the length of time between event repetitions is fixed) or aperiodic (i.e. the length of time between event repetitions varies). Therefore, we distinguish between periodic and aperiodic frequencies. In the SI system, periodic frequency is measured in hertz (Hz) or multiples of hertz, while aperiodic frequency is measured in becquerel (Bq).

quantity:Frequency
Property Value
qudt:description Frequency is the number of occurrences of a repeatiing event per unit time. The repetition of the events may be periodic (i.e. the length of time between event repetitions is fixed) or aperiodic (i.e. the length of time between event repetitions varies). Therefore, we distinguish between periodic and aperiodic frequencies. In the SI system, periodic frequency is measured in hertz (Hz) or multiples of hertz, while aperiodic frequency is measured in becquerel (Bq).

quantity:MachNumber: Mach Number

Mach number (Ma) is the speed of an object moving through air, or any fluid substance, divided by the speed of sound as it is in that substance: M = V_o/V_s where M is the Mach number V_o is the velocity of the object relative to the medium and V_s is the velocity of sound in the medium The Mach number is commonly used both with objects traveling at high speed in a fluid, and with high-speed fluid flows inside channels such as nozzles, diffusers or wind tunnels. As it is defined as a ratio of two speeds, it is a dimensionless number. [Wikipedia]

quantity:MachNumber
Property Value
qudt:description Mach number (Ma) is the speed of an object moving through air, or any fluid substance, divided by the speed of sound as it is in that substance: M = V_o/V_s where M is the Mach number V_o is the velocity of the object relative to the medium and V_s is the velocity of sound in the medium The Mach number is commonly used both with objects traveling at high speed in a fluid, and with high-speed fluid flows inside channels such as nozzles, diffusers or wind tunnels. As it is defined as a ratio of two speeds, it is a dimensionless number. [Wikipedia]
qudt:generalization quantity:DimensionlessRatio

quantity:SolidAngle: Solid Angle

The solid angle subtended by a surface S is defined as the surface area of a unit sphere covered by the surface S's projection onto the sphere. A solid angle is related to the surface of a sphere in the same way an ordinary angle is related to the circumference of a circle. Since the total surface area of the unit sphere is 4*pi, the measure of solid angle will always be between 0 and 4*pi.

quantity:SolidAngle
Property Value
qudt:description The solid angle subtended by a surface S is defined as the surface area of a unit sphere covered by the surface S's projection onto the sphere. A solid angle is related to the surface of a sphere in the same way an ordinary angle is related to the circumference of a circle. Since the total surface area of the unit sphere is 4*pi, the measure of solid angle will always be between 0 and 4*pi.
qudt:generalization quantity:Angle

quantity:Time: Time

Time is a basic component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects.

quantity:Time
Property Value
qudt:description Time is a basic component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects.
qudt:symbol T

quantity:Volume: Volume

The volume of a solid object is the three-dimensional concept of how much space it occupies, often quantified numerically. One-dimensional figures (such as lines) and two-dimensional shapes (such as squares) are assigned zero volume in the three-dimensional space.

quantity:Volume
Property Value
qudt:description The volume of a solid object is the three-dimensional concept of how much space it occupies, often quantified numerically. One-dimensional figures (such as lines) and two-dimensional shapes (such as squares) are assigned zero volume in the three-dimensional space.

Instances of qudt:SystemOfQuantities

quantity:SystemOfQuantities_CGS: CGS System of Quantities

quantity:SystemOfQuantities_CGS
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_CGS
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AngularAcceleration
qudt:systemDerivedQuantityKind quantity:AngularMomentum
qudt:systemDerivedQuantityKind quantity:AngularVelocity
qudt:systemDerivedQuantityKind quantity:Area
qudt:systemDerivedQuantityKind quantity:AreaAngle
qudt:systemDerivedQuantityKind quantity:AreaTime
qudt:systemDerivedQuantityKind quantity:Curvature
qudt:systemDerivedQuantityKind quantity:Density
qudt:systemDerivedQuantityKind quantity:DynamicViscosity
qudt:systemDerivedQuantityKind quantity:EnergyAndWork
qudt:systemDerivedQuantityKind quantity:EnergyDensity
qudt:systemDerivedQuantityKind quantity:EnergyPerArea
qudt:systemDerivedQuantityKind quantity:Force
qudt:systemDerivedQuantityKind quantity:ForcePerArea
qudt:systemDerivedQuantityKind quantity:ForcePerLength
qudt:systemDerivedQuantityKind quantity:Frequency
qudt:systemDerivedQuantityKind quantity:LengthMass
qudt:systemDerivedQuantityKind quantity:LinearAcceleration
qudt:systemDerivedQuantityKind quantity:LinearMomentum
qudt:systemDerivedQuantityKind quantity:LinearVelocity
qudt:systemDerivedQuantityKind quantity:MassPerArea
qudt:systemDerivedQuantityKind quantity:MassPerLength
qudt:systemDerivedQuantityKind quantity:MassPerTime
qudt:systemDerivedQuantityKind quantity:MomentOfInertia
qudt:systemDerivedQuantityKind quantity:Power
qudt:systemDerivedQuantityKind quantity:PowerPerArea
qudt:systemDerivedQuantityKind quantity:PowerPerAreaAngle
qudt:systemDerivedQuantityKind quantity:Pressure
qudt:systemDerivedQuantityKind quantity:RadiantIntensity
qudt:systemDerivedQuantityKind quantity:SpecificEnergy
qudt:systemDerivedQuantityKind quantity:Stress
qudt:systemDerivedQuantityKind quantity:TimeSquared
qudt:systemDerivedQuantityKind quantity:Torque
qudt:systemDerivedQuantityKind quantity:Volume
qudt:systemDerivedQuantityKind quantity:VolumePerUnitTime
qudt:systemDimension dim:Dimension_CGS_L
qudt:systemDimension dim:Dimension_CGS_L-1
qudt:systemDimension dim:Dimension_CGS_L-1M
qudt:systemDimension dim:Dimension_CGS_L-1MT-1
qudt:systemDimension dim:Dimension_CGS_L-1MT-2
qudt:systemDimension dim:Dimension_CGS_L-2M
qudt:systemDimension dim:Dimension_CGS_L-3M
qudt:systemDimension dim:Dimension_CGS_L2
qudt:systemDimension dim:Dimension_CGS_L2M
qudt:systemDimension dim:Dimension_CGS_L2MT-1
qudt:systemDimension dim:Dimension_CGS_L2MT-2
qudt:systemDimension dim:Dimension_CGS_L2MT-3
qudt:systemDimension dim:Dimension_CGS_L2T
qudt:systemDimension dim:Dimension_CGS_L2T-2
qudt:systemDimension dim:Dimension_CGS_L3
qudt:systemDimension dim:Dimension_CGS_L3T-1
qudt:systemDimension dim:Dimension_CGS_LM
qudt:systemDimension dim:Dimension_CGS_LMT-1
qudt:systemDimension dim:Dimension_CGS_LMT-2
qudt:systemDimension dim:Dimension_CGS_LT-1
qudt:systemDimension dim:Dimension_CGS_LT-2
qudt:systemDimension dim:Dimension_CGS_M
qudt:systemDimension dim:Dimension_CGS_MT-1
qudt:systemDimension dim:Dimension_CGS_MT-2
qudt:systemDimension dim:Dimension_CGS_MT-3
qudt:systemDimension dim:Dimension_CGS_T
qudt:systemDimension dim:Dimension_CGS_T-1
qudt:systemDimension dim:Dimension_CGS_T2
qudt:systemDimension dim:Dimension_CGS_U
qudt:systemDimension dim:Dimension_CGS_U-1L2MT-3
qudt:systemDimension dim:Dimension_CGS_U-1MT-3
qudt:systemDimension dim:Dimension_CGS_UL2
qudt:systemDimension dim:Dimension_CGS_UT-1
qudt:systemDimension dim:Dimension_CGS_UT-2
qudt:unitSystem unit:SystemOfUnits_CGS

quantity:SystemOfQuantities_CGS-EMU: CGS-EMU System of Quantities

quantity:SystemOfQuantities_CGS-EMU
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_CGS
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AuxillaryMagneticField
qudt:systemDerivedQuantityKind quantity:Capacitance
qudt:systemDerivedQuantityKind quantity:ElectricCharge
qudt:systemDerivedQuantityKind quantity:ElectricConductivity
qudt:systemDerivedQuantityKind quantity:ElectricCurrent
qudt:systemDerivedQuantityKind quantity:ElectricCurrentDensity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitLength
qudt:systemDerivedQuantityKind quantity:ElectricDipoleMoment
qudt:systemDerivedQuantityKind quantity:ElectricDisplacementField
qudt:systemDerivedQuantityKind quantity:ElectricField
qudt:systemDerivedQuantityKind quantity:ElectricFlux
qudt:systemDerivedQuantityKind quantity:ElectricPotential
qudt:systemDerivedQuantityKind quantity:ElectromotiveForce
qudt:systemDerivedQuantityKind quantity:EnergyPerElectricCharge
qudt:systemDerivedQuantityKind quantity:Inductance
qudt:systemDerivedQuantityKind quantity:LengthPerUnitElectricCurrent
qudt:systemDerivedQuantityKind quantity:MagneticDipoleMoment
qudt:systemDerivedQuantityKind quantity:MagneticField
qudt:systemDerivedQuantityKind quantity:MagneticFlux
qudt:systemDerivedQuantityKind quantity:MagneticFluxPerUnitLength
qudt:systemDerivedQuantityKind quantity:MagnetizationField
qudt:systemDerivedQuantityKind quantity:MagnetomotiveForce
qudt:systemDerivedQuantityKind quantity:Permeability
qudt:systemDerivedQuantityKind quantity:Permittivity
qudt:systemDerivedQuantityKind quantity:Resistance
qudt:systemDimension dim:Dimension_CGS-EMU-L-1T
qudt:systemDimension dim:Dimension_CGS-EMU_L
qudt:systemDimension dim:Dimension_CGS-EMU_L-0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-EMU_L-1.5M0.5
qudt:systemDimension dim:Dimension_CGS-EMU_L-1.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-EMU_L-1T2
qudt:systemDimension dim:Dimension_CGS-EMU_L-2T2
qudt:systemDimension dim:Dimension_CGS-EMU_L0.5M0.5
qudt:systemDimension dim:Dimension_CGS-EMU_L0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-EMU_L0.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-EMU_L1.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-EMU_L1.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-EMU_LT-1
qudt:systemDimension dim:Dimension_CGS-EMU_M
qudt:systemDimension dim:Dimension_CGS-EMU_T
qudt:systemDimension dim:Dimension_CGS-EMU_U
qudt:unitSystem unit:SystemOfUnits_CGS-EMU

quantity:SystemOfQuantities_CGS-ESU: CGS-ESU System of Quantities

quantity:SystemOfQuantities_CGS-ESU
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_CGS
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AuxillaryMagneticField
qudt:systemDerivedQuantityKind quantity:Capacitance
qudt:systemDerivedQuantityKind quantity:ElectricCharge
qudt:systemDerivedQuantityKind quantity:ElectricCurrent
qudt:systemDerivedQuantityKind quantity:ElectricCurrentDensity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitLength
qudt:systemDerivedQuantityKind quantity:ElectricDipoleMoment
qudt:systemDerivedQuantityKind quantity:ElectricDisplacementField
qudt:systemDerivedQuantityKind quantity:ElectricField
qudt:systemDerivedQuantityKind quantity:ElectricFlux
qudt:systemDerivedQuantityKind quantity:ElectricPotential
qudt:systemDerivedQuantityKind quantity:ElectromotiveForce
qudt:systemDerivedQuantityKind quantity:EnergyPerElectricCharge
qudt:systemDerivedQuantityKind quantity:Inductance
qudt:systemDerivedQuantityKind quantity:LengthPerUnitElectricCurrent
qudt:systemDerivedQuantityKind quantity:MagneticDipoleMoment
qudt:systemDerivedQuantityKind quantity:MagneticField
qudt:systemDerivedQuantityKind quantity:MagneticFlux
qudt:systemDerivedQuantityKind quantity:MagneticFluxPerUnitLength
qudt:systemDerivedQuantityKind quantity:MagnetizationField
qudt:systemDerivedQuantityKind quantity:MagnetomotiveForce
qudt:systemDerivedQuantityKind quantity:Permeability
qudt:systemDerivedQuantityKind quantity:Permittivity
qudt:systemDerivedQuantityKind quantity:Resistance
qudt:systemDimension dim:Dimension_CGS-ESU_L
qudt:systemDimension dim:Dimension_CGS-ESU_L-0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-ESU_L-0.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-ESU_L-1.5M0.5
qudt:systemDimension dim:Dimension_CGS-ESU_L-1T
qudt:systemDimension dim:Dimension_CGS-ESU_L-1T2
qudt:systemDimension dim:Dimension_CGS-ESU_L-2T2
qudt:systemDimension dim:Dimension_CGS-ESU_L0.5M0.5
qudt:systemDimension dim:Dimension_CGS-ESU_L0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-ESU_L0.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-ESU_L1.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-ESU_L1.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-ESU_M
qudt:systemDimension dim:Dimension_CGS-ESU_T
qudt:systemDimension dim:Dimension_CGS-ESU_U
qudt:unitSystem unit:SystemOfUnits_CGS-ESU

quantity:SystemOfQuantities_CGS-Gauss: CGS-Gauss System of Quantities

quantity:SystemOfQuantities_CGS-Gauss
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_CGS
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AuxillaryMagneticField
qudt:systemDerivedQuantityKind quantity:Capacitance
qudt:systemDerivedQuantityKind quantity:ElectricCharge
qudt:systemDerivedQuantityKind quantity:ElectricCurrent
qudt:systemDerivedQuantityKind quantity:ElectricCurrentDensity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitLength
qudt:systemDerivedQuantityKind quantity:ElectricDipoleMoment
qudt:systemDerivedQuantityKind quantity:ElectricDisplacementField
qudt:systemDerivedQuantityKind quantity:ElectricField
qudt:systemDerivedQuantityKind quantity:ElectricFlux
qudt:systemDerivedQuantityKind quantity:ElectricPotential
qudt:systemDerivedQuantityKind quantity:ElectromotiveForce
qudt:systemDerivedQuantityKind quantity:EnergyPerElectricCharge
qudt:systemDerivedQuantityKind quantity:Inductance
qudt:systemDerivedQuantityKind quantity:LengthPerUnitElectricCurrent
qudt:systemDerivedQuantityKind quantity:MagneticDipoleMoment
qudt:systemDerivedQuantityKind quantity:MagneticField
qudt:systemDerivedQuantityKind quantity:MagneticFlux
qudt:systemDerivedQuantityKind quantity:MagneticFluxPerUnitLength
qudt:systemDerivedQuantityKind quantity:MagnetizationField
qudt:systemDerivedQuantityKind quantity:Permeability
qudt:systemDerivedQuantityKind quantity:Permittivity
qudt:systemDerivedQuantityKind quantity:Resistance
qudt:systemDimension dim:Dimension_CGS-Gauss_L
qudt:systemDimension dim:Dimension_CGS-Gauss_L-0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-Gauss_L-1T
qudt:systemDimension dim:Dimension_CGS-Gauss_L-1T2
qudt:systemDimension dim:Dimension_CGS-Gauss_L0.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-Gauss_L1.5M0.5T-1
qudt:systemDimension dim:Dimension_CGS-Gauss_L1.5M0.5T-2
qudt:systemDimension dim:Dimension_CGS-Gauss_M
qudt:systemDimension dim:Dimension_CGS-Gauss_T
qudt:systemDimension dim:Dimension_CGS-Gauss_U
qudt:unitSystem unit:SystemOfUnits_CGS-Gauss

quantity:SystemOfQuantities_Planck: Planck System of Quantities

quantity:SystemOfQuantities_Planck
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_Planck
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:ElectricCharge
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:ThermodynamicTemperature
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:Area
qudt:systemDerivedQuantityKind quantity:AuxillaryMagneticField
qudt:systemDerivedQuantityKind quantity:Density
qudt:systemDerivedQuantityKind quantity:ElectricCurrent
qudt:systemDerivedQuantityKind quantity:ElectricCurrentDensity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitLength
qudt:systemDerivedQuantityKind quantity:ElectricDipoleMoment
qudt:systemDerivedQuantityKind quantity:ElectricDisplacementField
qudt:systemDerivedQuantityKind quantity:ElectricField
qudt:systemDerivedQuantityKind quantity:ElectricFlux
qudt:systemDerivedQuantityKind quantity:ElectricPotential
qudt:systemDerivedQuantityKind quantity:ElectromotiveForce
qudt:systemDerivedQuantityKind quantity:EnergyAndWork
qudt:systemDerivedQuantityKind quantity:EnergyPerElectricCharge
qudt:systemDerivedQuantityKind quantity:Force
qudt:systemDerivedQuantityKind quantity:ForcePerArea
qudt:systemDerivedQuantityKind quantity:Frequency
qudt:systemDerivedQuantityKind quantity:LengthPerUnitElectricCurrent
qudt:systemDerivedQuantityKind quantity:LinearAcceleration
qudt:systemDerivedQuantityKind quantity:LinearMomentum
qudt:systemDerivedQuantityKind quantity:LinearVelocity
qudt:systemDerivedQuantityKind quantity:MagneticDipoleMoment
qudt:systemDerivedQuantityKind quantity:MagneticField
qudt:systemDerivedQuantityKind quantity:MagneticFlux
qudt:systemDerivedQuantityKind quantity:MagneticFluxPerUnitLength
qudt:systemDerivedQuantityKind quantity:MagnetizationField
qudt:systemDerivedQuantityKind quantity:Power
qudt:systemDerivedQuantityKind quantity:Pressure
qudt:systemDerivedQuantityKind quantity:Resistance
qudt:systemDerivedQuantityKind quantity:Stress
qudt:systemDerivedQuantityKind quantity:Torque
qudt:systemDerivedQuantityKind quantity:Volume
qudt:systemDimension dim:Dimension_Planck_L
qudt:systemDimension dim:Dimension_Planck_L-1MT-2
qudt:systemDimension dim:Dimension_Planck_L-2T-1Q
qudt:systemDimension dim:Dimension_Planck_L-3M
qudt:systemDimension dim:Dimension_Planck_L2
qudt:systemDimension dim:Dimension_Planck_L2MT-1Q-2
qudt:systemDimension dim:Dimension_Planck_L2MT-2
qudt:systemDimension dim:Dimension_Planck_L2MT-2Q-1
qudt:systemDimension dim:Dimension_Planck_L2MT-3
qudt:systemDimension dim:Dimension_Planck_L3
qudt:systemDimension dim:Dimension_Planck_LMT-1
qudt:systemDimension dim:Dimension_Planck_LMT-2
qudt:systemDimension dim:Dimension_Planck_LT-1
qudt:systemDimension dim:Dimension_Planck_LT-2
qudt:systemDimension dim:Dimension_Planck_M
qudt:systemDimension dim:Dimension_Planck_MT-1Q-1
qudt:systemDimension dim:Dimension_Planck_Q
qudt:systemDimension dim:Dimension_Planck_T
qudt:systemDimension dim:Dimension_Planck_T-1
qudt:systemDimension dim:Dimension_Planck_T-1Q
qudt:systemDimension dim:Dimension_Planck_U
qudt:systemDimension dim:Dimension_Planck_?
qudt:unitSystem unit:SystemOfUnits_Planck

quantity:SystemOfQuantities_SI: International System of Quantities

quantity:SystemOfQuantities_SI
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_SI
qudt:systemBaseQuantityKind quantity:AmountOfSubstance
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:ElectricCurrent
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:LuminousIntensity
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:ThermodynamicTemperature
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AbsorbedDose
qudt:systemDerivedQuantityKind quantity:AbsorbedDoseRate
qudt:systemDerivedQuantityKind quantity:Activity
qudt:systemDerivedQuantityKind quantity:AmountOfSubstancePerUnitMass
qudt:systemDerivedQuantityKind quantity:AmountOfSubstancePerUnitVolume
qudt:systemDerivedQuantityKind quantity:AngularAcceleration
qudt:systemDerivedQuantityKind quantity:AngularMomentum
qudt:systemDerivedQuantityKind quantity:AngularVelocity
qudt:systemDerivedQuantityKind quantity:Area
qudt:systemDerivedQuantityKind quantity:AreaAngle
qudt:systemDerivedQuantityKind quantity:AreaPerTime
qudt:systemDerivedQuantityKind quantity:AreaTemperature
qudt:systemDerivedQuantityKind quantity:AreaThermalExpansion
qudt:systemDerivedQuantityKind quantity:AreaTime
qudt:systemDerivedQuantityKind quantity:AuxillaryMagneticField
qudt:systemDerivedQuantityKind quantity:Capacitance
qudt:systemDerivedQuantityKind quantity:CatalyticActivity
qudt:systemDerivedQuantityKind quantity:CoefficientOfHeatTransfer
qudt:systemDerivedQuantityKind quantity:CubicElectricDipoleMomentPerSquareEnergy
qudt:systemDerivedQuantityKind quantity:Density
qudt:systemDerivedQuantityKind quantity:DoseEquivalent
qudt:systemDerivedQuantityKind quantity:DynamicViscosity
qudt:systemDerivedQuantityKind quantity:ElectricCharge
qudt:systemDerivedQuantityKind quantity:ElectricChargeLineDensity
qudt:systemDerivedQuantityKind quantity:ElectricChargePerAmountOfSubstance
qudt:systemDerivedQuantityKind quantity:ElectricChargePerArea
qudt:systemDerivedQuantityKind quantity:ElectricChargePerMass
qudt:systemDerivedQuantityKind quantity:ElectricChargeVolumeDensity
qudt:systemDerivedQuantityKind quantity:ElectricConductivity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentDensity
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerAngle
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitEnergy
qudt:systemDerivedQuantityKind quantity:ElectricCurrentPerUnitLength
qudt:systemDerivedQuantityKind quantity:ElectricDipoleMoment
qudt:systemDerivedQuantityKind quantity:ElectricDisplacementField
qudt:systemDerivedQuantityKind quantity:ElectricField
qudt:systemDerivedQuantityKind quantity:ElectricFlux
qudt:systemDerivedQuantityKind quantity:ElectricPotential
qudt:systemDerivedQuantityKind quantity:ElectricQuadrupoleMoment
qudt:systemDerivedQuantityKind quantity:ElectromotiveForce
qudt:systemDerivedQuantityKind quantity:EnergyAndWork
qudt:systemDerivedQuantityKind quantity:EnergyDensity
qudt:systemDerivedQuantityKind quantity:EnergyPerArea
qudt:systemDerivedQuantityKind quantity:EnergyPerAreaElectricCharge
qudt:systemDerivedQuantityKind quantity:EnergyPerElectricCharge
qudt:systemDerivedQuantityKind quantity:EnergyPerSquareMagneticFluxDensity
qudt:systemDerivedQuantityKind quantity:Exposure
qudt:systemDerivedQuantityKind quantity:Force
qudt:systemDerivedQuantityKind quantity:ForcePerArea
qudt:systemDerivedQuantityKind quantity:ForcePerAreaTime
qudt:systemDerivedQuantityKind quantity:ForcePerElectricCharge
qudt:systemDerivedQuantityKind quantity:ForcePerLength
qudt:systemDerivedQuantityKind quantity:Frequency
qudt:systemDerivedQuantityKind quantity:GravitationalAttraction
qudt:systemDerivedQuantityKind quantity:HeatCapacity
qudt:systemDerivedQuantityKind quantity:HeatFlowRate
qudt:systemDerivedQuantityKind quantity:HeatFlowRatePerUnitArea
qudt:systemDerivedQuantityKind quantity:Illuminance
qudt:systemDerivedQuantityKind quantity:Inductance
qudt:systemDerivedQuantityKind quantity:InverseAmountOfSubstance
qudt:systemDerivedQuantityKind quantity:InverseEnergy
qudt:systemDerivedQuantityKind quantity:InverseLength
qudt:systemDerivedQuantityKind quantity:InverseLengthTemperature
qudt:systemDerivedQuantityKind quantity:InverseMagneticFlux
qudt:systemDerivedQuantityKind quantity:InversePermittivity
qudt:systemDerivedQuantityKind quantity:InverseSquareEnergy
qudt:systemDerivedQuantityKind quantity:InverseTimeTemperature
qudt:systemDerivedQuantityKind quantity:InverseVolume
qudt:systemDerivedQuantityKind quantity:KinematicViscosity
qudt:systemDerivedQuantityKind quantity:LengthEnergy
qudt:systemDerivedQuantityKind quantity:LengthMass
qudt:systemDerivedQuantityKind quantity:LengthMolarEnergy
qudt:systemDerivedQuantityKind quantity:LengthPerUnitElectricCurrent
qudt:systemDerivedQuantityKind quantity:LengthPerUnitMagneticFlux
qudt:systemDerivedQuantityKind quantity:LengthTemperature
qudt:systemDerivedQuantityKind quantity:LinearAcceleration
qudt:systemDerivedQuantityKind quantity:LinearMomentum
qudt:systemDerivedQuantityKind quantity:LinearThermalExpansion
qudt:systemDerivedQuantityKind quantity:LinearVelocity
qudt:systemDerivedQuantityKind quantity:Luminance
qudt:systemDerivedQuantityKind quantity:LuminousEfficacy
qudt:systemDerivedQuantityKind quantity:LuminousEnergy
qudt:systemDerivedQuantityKind quantity:LuminousFlux
qudt:systemDerivedQuantityKind quantity:LuminousFluxPerArea
qudt:systemDerivedQuantityKind quantity:MagneticDipoleMoment
qudt:systemDerivedQuantityKind quantity:MagneticField
qudt:systemDerivedQuantityKind quantity:MagneticFlux
qudt:systemDerivedQuantityKind quantity:MagneticFluxPerUnitLength
qudt:systemDerivedQuantityKind quantity:MagnetizationField
qudt:systemDerivedQuantityKind quantity:MagnetomotiveForce
qudt:systemDerivedQuantityKind quantity:MassPerArea
qudt:systemDerivedQuantityKind quantity:MassPerAreaTime
qudt:systemDerivedQuantityKind quantity:MassPerElectricCharge
qudt:systemDerivedQuantityKind quantity:MassPerLength
qudt:systemDerivedQuantityKind quantity:MassPerTime
qudt:systemDerivedQuantityKind quantity:MassTemperature
qudt:systemDerivedQuantityKind quantity:MolarAngularMomentum
qudt:systemDerivedQuantityKind quantity:MolarEnergy
qudt:systemDerivedQuantityKind quantity:MolarHeatCapacity
qudt:systemDerivedQuantityKind quantity:MolarMass
qudt:systemDerivedQuantityKind quantity:MolarVolume
qudt:systemDerivedQuantityKind quantity:MomentOfInertia
qudt:systemDerivedQuantityKind quantity:Permeability
qudt:systemDerivedQuantityKind quantity:Permittivity
qudt:systemDerivedQuantityKind quantity:PlaneAngle
qudt:systemDerivedQuantityKind quantity:Polarizability
qudt:systemDerivedQuantityKind quantity:PolarizationField
qudt:systemDerivedQuantityKind quantity:Power
qudt:systemDerivedQuantityKind quantity:PowerArea
qudt:systemDerivedQuantityKind quantity:PowerAreaPerSolidAngle
qudt:systemDerivedQuantityKind quantity:PowerPerArea
qudt:systemDerivedQuantityKind quantity:PowerPerAreaAngle
qudt:systemDerivedQuantityKind quantity:PowerPerAreaQuarticTemperature
qudt:systemDerivedQuantityKind quantity:PowerPerElectricCharge
qudt:systemDerivedQuantityKind quantity:QuarticElectricDipoleMomentPerCubicEnergy
qudt:systemDerivedQuantityKind quantity:RadiantIntensity
qudt:systemDerivedQuantityKind quantity:Resistance
qudt:systemDerivedQuantityKind quantity:SolidAngle
qudt:systemDerivedQuantityKind quantity:SpecificEnergy
qudt:systemDerivedQuantityKind quantity:SpecificHeatCapacity
qudt:systemDerivedQuantityKind quantity:SpecificHeatPressure
qudt:systemDerivedQuantityKind quantity:SpecificHeatVolume
qudt:systemDerivedQuantityKind quantity:SpecificImpulseByMass
qudt:systemDerivedQuantityKind quantity:SpecificVolume
qudt:systemDerivedQuantityKind quantity:SquareEnergy
qudt:systemDerivedQuantityKind quantity:StandardGravitationalParameter
qudt:systemDerivedQuantityKind quantity:Stress
qudt:systemDerivedQuantityKind quantity:TemperatureAmountOfSubstance
qudt:systemDerivedQuantityKind quantity:TemperaturePerMagneticFluxDensity
qudt:systemDerivedQuantityKind quantity:TemperaturePerTime
qudt:systemDerivedQuantityKind quantity:ThermalConductivity
qudt:systemDerivedQuantityKind quantity:ThermalDiffusivity
qudt:systemDerivedQuantityKind quantity:ThermalInsulance
qudt:systemDerivedQuantityKind quantity:ThermalResistance
qudt:systemDerivedQuantityKind quantity:ThermalResistivity
qudt:systemDerivedQuantityKind quantity:ThrustToMassRatio
qudt:systemDerivedQuantityKind quantity:TimeSquared
qudt:systemDerivedQuantityKind quantity:TimeTemperature
qudt:systemDerivedQuantityKind quantity:Torque
qudt:systemDerivedQuantityKind quantity:Volume
qudt:systemDerivedQuantityKind quantity:VolumePerUnitTime
qudt:systemDerivedQuantityKind quantity:VolumeThermalExpansion
qudt:systemDerivedQuantityKind quantity:VolumetricHeatCapacity
qudt:systemDimension dim:Dimension_MT-3?-4
qudt:systemDimension dim:Dimension_SI_I
qudt:systemDimension dim:Dimension_SI_J
qudt:systemDimension dim:Dimension_SI_L
qudt:systemDimension dim:Dimension_SI_L-1
qudt:systemDimension dim:Dimension_SI_L-1I
qudt:systemDimension dim:Dimension_SI_L-1M
qudt:systemDimension dim:Dimension_SI_L-1M-1T2I
qudt:systemDimension dim:Dimension_SI_L-1M-1T3?
qudt:systemDimension dim:Dimension_SI_L-1M-2T7I3
qudt:systemDimension dim:Dimension_SI_L-1MT-1
qudt:systemDimension dim:Dimension_SI_L-1MT-2
qudt:systemDimension dim:Dimension_SI_L-1MT-2?-1
qudt:systemDimension dim:Dimension_SI_L-1MT-3
qudt:systemDimension dim:Dimension_SI_L-1T-2?-1
qudt:systemDimension dim:Dimension_SI_L-1TI
qudt:systemDimension dim:Dimension_SI_L-1?-1
qudt:systemDimension dim:Dimension_SI_L-2I
qudt:systemDimension dim:Dimension_SI_L-2J
qudt:systemDimension dim:Dimension_SI_L-2M
qudt:systemDimension dim:Dimension_SI_L-2M-1T2
qudt:systemDimension dim:Dimension_SI_L-2M-1T2I
qudt:systemDimension dim:Dimension_SI_L-2M-1T3I
qudt:systemDimension dim:Dimension_SI_L-2M-1T3I2
qudt:systemDimension dim:Dimension_SI_L-2M-1T3?
qudt:systemDimension dim:Dimension_SI_L-2M-1T4I2
qudt:systemDimension dim:Dimension_SI_L-2M-3T10I4
qudt:systemDimension dim:Dimension_SI_L-2MT-1
qudt:systemDimension dim:Dimension_SI_L-2TI
qudt:systemDimension dim:Dimension_SI_L-3
qudt:systemDimension dim:Dimension_SI_L-3M
qudt:systemDimension dim:Dimension_SI_L-3M-1T4I2
qudt:systemDimension dim:Dimension_SI_L-3N
qudt:systemDimension dim:Dimension_SI_L-3TI
qudt:systemDimension dim:Dimension_SI_L-4M-2T4
qudt:systemDimension dim:Dimension_SI_L2
qudt:systemDimension dim:Dimension_SI_L2I
qudt:systemDimension dim:Dimension_SI_L2M
qudt:systemDimension dim:Dimension_SI_L2M-1T2I2
qudt:systemDimension dim:Dimension_SI_L2MT-1
qudt:systemDimension dim:Dimension_SI_L2MT-1N-1
qudt:systemDimension dim:Dimension_SI_L2MT-2
qudt:systemDimension dim:Dimension_SI_L2MT-2I-1
qudt:systemDimension dim:Dimension_SI_L2MT-2I-2
qudt:systemDimension dim:Dimension_SI_L2MT-2N-1
qudt:systemDimension dim:Dimension_SI_L2MT-2?-1
qudt:systemDimension dim:Dimension_SI_L2MT-2?-1N-1
qudt:systemDimension dim:Dimension_SI_L2MT-3
qudt:systemDimension dim:Dimension_SI_L2MT-3I-1
qudt:systemDimension dim:Dimension_SI_L2MT-3I-2
qudt:systemDimension dim:Dimension_SI_L2MT-4I-1
qudt:systemDimension dim:Dimension_SI_L2T
qudt:systemDimension dim:Dimension_SI_L2T-1
qudt:systemDimension dim:Dimension_SI_L2T-2
qudt:systemDimension dim:Dimension_SI_L2T-2?-1
qudt:systemDimension dim:Dimension_SI_L2T-3
qudt:systemDimension dim:Dimension_SI_L2TI
qudt:systemDimension dim:Dimension_SI_L2?
qudt:systemDimension dim:Dimension_SI_L2?-1
qudt:systemDimension dim:Dimension_SI_L3
qudt:systemDimension dim:Dimension_SI_L3M-1
qudt:systemDimension dim:Dimension_SI_L3M-1T-2
qudt:systemDimension dim:Dimension_SI_L3M-1?-1
qudt:systemDimension dim:Dimension_SI_L3MT-2
qudt:systemDimension dim:Dimension_SI_L3MT-2N-1
qudt:systemDimension dim:Dimension_SI_L3MT-3I-1
qudt:systemDimension dim:Dimension_SI_L3MT-4I-2
qudt:systemDimension dim:Dimension_SI_L3N-1
qudt:systemDimension dim:Dimension_SI_L3T-1
qudt:systemDimension dim:Dimension_SI_L3T-2
qudt:systemDimension dim:Dimension_SI_L3?-1
qudt:systemDimension dim:Dimension_SI_L4M2T-4
qudt:systemDimension dim:Dimension_SI_L4MT-3
qudt:systemDimension dim:Dimension_SI_LI-1
qudt:systemDimension dim:Dimension_SI_LM
qudt:systemDimension dim:Dimension_SI_LMT-1
qudt:systemDimension dim:Dimension_SI_LMT-2
qudt:systemDimension dim:Dimension_SI_LMT-2I-1
qudt:systemDimension dim:Dimension_SI_LMT-2I-2
qudt:systemDimension dim:Dimension_SI_LMT-3I-1
qudt:systemDimension dim:Dimension_SI_LMT-3?-1
qudt:systemDimension dim:Dimension_SI_LT-1
qudt:systemDimension dim:Dimension_SI_LT-2
qudt:systemDimension dim:Dimension_SI_LTI
qudt:systemDimension dim:Dimension_SI_L?
qudt:systemDimension dim:Dimension_SI_L?-1
qudt:systemDimension dim:Dimension_SI_M
qudt:systemDimension dim:Dimension_SI_M-1N
qudt:systemDimension dim:Dimension_SI_M-1T2I?
qudt:systemDimension dim:Dimension_SI_M-1T3?
qudt:systemDimension dim:Dimension_SI_M-1T4I2
qudt:systemDimension dim:Dimension_SI_M-1TI
qudt:systemDimension dim:Dimension_SI_MN-1
qudt:systemDimension dim:Dimension_SI_MT-1
qudt:systemDimension dim:Dimension_SI_MT-1I-1
qudt:systemDimension dim:Dimension_SI_MT-2
qudt:systemDimension dim:Dimension_SI_MT-2I-1
qudt:systemDimension dim:Dimension_SI_MT-3
qudt:systemDimension dim:Dimension_SI_MT-3I-1
qudt:systemDimension dim:Dimension_SI_MT-3?-1
qudt:systemDimension dim:Dimension_SI_M?
qudt:systemDimension dim:Dimension_SI_N
qudt:systemDimension dim:Dimension_SI_N-1
qudt:systemDimension dim:Dimension_SI_T
qudt:systemDimension dim:Dimension_SI_T-1
qudt:systemDimension dim:Dimension_SI_T-1N
qudt:systemDimension dim:Dimension_SI_T-1?
qudt:systemDimension dim:Dimension_SI_T-1?-1
qudt:systemDimension dim:Dimension_SI_T2
qudt:systemDimension dim:Dimension_SI_TI
qudt:systemDimension dim:Dimension_SI_TIN-1
qudt:systemDimension dim:Dimension_SI_T?
qudt:systemDimension dim:Dimension_SI_U
qudt:systemDimension dim:Dimension_SI_U-1I
qudt:systemDimension dim:Dimension_SI_U-1L2MT-3
qudt:systemDimension dim:Dimension_SI_U-1L4MT-3
qudt:systemDimension dim:Dimension_SI_U-1MT-3
qudt:systemDimension dim:Dimension_SI_UI
qudt:systemDimension dim:Dimension_SI_UJ
qudt:systemDimension dim:Dimension_SI_UL-2J
qudt:systemDimension dim:Dimension_SI_UL-2M-1T3J
qudt:systemDimension dim:Dimension_SI_UL2
qudt:systemDimension dim:Dimension_SI_UT-1
qudt:systemDimension dim:Dimension_SI_UT-2
qudt:systemDimension dim:Dimension_SI_?
qudt:systemDimension dim:Dimension_SI_?N
qudt:unitSystem unit:SystemOfUnits_SI

quantity:SystemOfQuantities_USCustomary: US Customary System of Quantities

quantity:SystemOfQuantities_USCustomary
Property Value
qudt:baseDimensionEnumeration dim:SystemBaseDimensionEnumeration_USCustomary
qudt:systemBaseQuantityKind quantity:Dimensionless
qudt:systemBaseQuantityKind quantity:Length
qudt:systemBaseQuantityKind quantity:Mass
qudt:systemBaseQuantityKind quantity:ThermodynamicTemperature
qudt:systemBaseQuantityKind quantity:Time
qudt:systemDerivedQuantityKind quantity:AngularAcceleration
qudt:systemDerivedQuantityKind quantity:AngularVelocity
qudt:systemDerivedQuantityKind quantity:Area
qudt:systemDerivedQuantityKind quantity:AreaTemperature
qudt:systemDerivedQuantityKind quantity:AreaTime
qudt:systemDerivedQuantityKind quantity:AreaTimeTemperature
qudt:systemDerivedQuantityKind quantity:CoefficientOfHeatTransfer
qudt:systemDerivedQuantityKind quantity:Density
qudt:systemDerivedQuantityKind quantity:DryVolume
qudt:systemDerivedQuantityKind quantity:DynamicViscosity
qudt:systemDerivedQuantityKind quantity:EnergyAndWork
qudt:systemDerivedQuantityKind quantity:EnergyPerArea
qudt:systemDerivedQuantityKind quantity:Force
qudt:systemDerivedQuantityKind quantity:ForcePerArea
qudt:systemDerivedQuantityKind quantity:ForcePerLength
qudt:systemDerivedQuantityKind quantity:HeatCapacity
qudt:systemDerivedQuantityKind quantity:HeatFlowRate
qudt:systemDerivedQuantityKind quantity:HeatFlowRatePerUnitArea
qudt:systemDerivedQuantityKind quantity:KinematicViscosity
qudt:systemDerivedQuantityKind quantity:LinearAcceleration
qudt:systemDerivedQuantityKind quantity:LinearVelocity
qudt:systemDerivedQuantityKind quantity:LiquidVolume
qudt:systemDerivedQuantityKind quantity:MassPerArea
qudt:systemDerivedQuantityKind quantity:MassPerLength
qudt:systemDerivedQuantityKind quantity:MassPerTime
qudt:systemDerivedQuantityKind quantity:MassTemperature
qudt:systemDerivedQuantityKind quantity:PlaneAngle
qudt:systemDerivedQuantityKind quantity:Power
qudt:systemDerivedQuantityKind quantity:PowerPerArea
qudt:systemDerivedQuantityKind quantity:Pressure
qudt:systemDerivedQuantityKind quantity:SpecificEnergy
qudt:systemDerivedQuantityKind quantity:SpecificHeatCapacity
qudt:systemDerivedQuantityKind quantity:Stress
qudt:systemDerivedQuantityKind quantity:ThermalConductivity
qudt:systemDerivedQuantityKind quantity:ThermalDiffusivity
qudt:systemDerivedQuantityKind quantity:ThermalEnergy
qudt:systemDerivedQuantityKind quantity:ThermalEnergyLength
qudt:systemDerivedQuantityKind quantity:ThermalInsulance
qudt:systemDerivedQuantityKind quantity:ThermalResistance
qudt:systemDerivedQuantityKind quantity:ThermalResistivity
qudt:systemDerivedQuantityKind quantity:ThrustToMassRatio
qudt:systemDerivedQuantityKind quantity:TimeSquared
qudt:systemDerivedQuantityKind quantity:Torque
qudt:systemDerivedQuantityKind quantity:Volume
qudt:systemDerivedQuantityKind quantity:VolumePerUnitTime
qudt:systemDimension dim:Dimension_USCustomary_L
qudt:systemDimension dim:Dimension_USCustomary_L-1M
qudt:systemDimension dim:Dimension_USCustomary_L-1M-1T3?
qudt:systemDimension dim:Dimension_USCustomary_L-1MT-1
qudt:systemDimension dim:Dimension_USCustomary_L-1MT-2
qudt:systemDimension dim:Dimension_USCustomary_L-2M
qudt:systemDimension dim:Dimension_USCustomary_L-2M-1T3?
qudt:systemDimension dim:Dimension_USCustomary_L-3M
qudt:systemDimension dim:Dimension_USCustomary_L2
qudt:systemDimension dim:Dimension_USCustomary_L2MT-2
qudt:systemDimension dim:Dimension_USCustomary_L2MT-2?-1
qudt:systemDimension dim:Dimension_USCustomary_L2MT-3
qudt:systemDimension dim:Dimension_USCustomary_L2T
qudt:systemDimension dim:Dimension_USCustomary_L2T-1
qudt:systemDimension dim:Dimension_USCustomary_L2T-2
qudt:systemDimension dim:Dimension_USCustomary_L2T-2?-1
qudt:systemDimension dim:Dimension_USCustomary_L2T?
qudt:systemDimension dim:Dimension_USCustomary_L2?
qudt:systemDimension dim:Dimension_USCustomary_L3
qudt:systemDimension dim:Dimension_USCustomary_L3MT-2
qudt:systemDimension dim:Dimension_USCustomary_L3T-1
qudt:systemDimension dim:Dimension_USCustomary_LMT-2
qudt:systemDimension dim:Dimension_USCustomary_LMT-3?-1
qudt:systemDimension dim:Dimension_USCustomary_LT-1
qudt:systemDimension dim:Dimension_USCustomary_LT-2
qudt:systemDimension dim:Dimension_USCustomary_M
qudt:systemDimension dim:Dimension_USCustomary_M-1T3?
qudt:systemDimension dim:Dimension_USCustomary_MT-1
qudt:systemDimension dim:Dimension_USCustomary_MT-2
qudt:systemDimension dim:Dimension_USCustomary_MT-3
qudt:systemDimension dim:Dimension_USCustomary_MT-3?-1
qudt:systemDimension dim:Dimension_USCustomary_M?
qudt:systemDimension dim:Dimension_USCustomary_T
qudt:systemDimension dim:Dimension_USCustomary_T2
qudt:systemDimension dim:Dimension_USCustomary_U
qudt:systemDimension dim:Dimension_USCustomary_UT-1
qudt:systemDimension dim:Dimension_USCustomary_UT-2
qudt:systemDimension dim:Dimension_USCustomary_?
qudt:unitSystem unit:SystemOfUnits_USCustomary

Instances of qudt:ThermodynamicsQuantityKind

quantity:AreaThermalExpansion: Area Thermal Expansion

When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

quantity:AreaThermalExpansion
Property Value
qudt:description When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

quantity:CompressibilityFactor: Compressibility Factor

The compressibility factor (Z) is a useful thermodynamic property for modifying the ideal gas law to account for the real gas behaviour. The closer a gas is to a phase change, the larger the deviations from ideal behavior. Values for compressibility are calculated using equations of state (EOS), such as the virial equation and van der Waals equation. The compressibility factor for specific gases can be obtained, with out calculation, from compressibility charts. These charts are created by plotting Z as a function of pressure at constant temperature.

quantity:CompressibilityFactor
Property Value
qudt:description The compressibility factor (Z) is a useful thermodynamic property for modifying the ideal gas law to account for the real gas behaviour. The closer a gas is to a phase change, the larger the deviations from ideal behavior. Values for compressibility are calculated using equations of state (EOS), such as the virial equation and van der Waals equation. The compressibility factor for specific gases can be obtained, with out calculation, from compressibility charts. These charts are created by plotting Z as a function of pressure at constant temperature.
qudt:generalization quantity:DimensionlessRatio
qudt:symbol Z

quantity:Enthalpy: Enthalpy

Static enthalpy per unit mass. The specific enthalpy of a working mass is a property of that mass used in thermodynamics, defined as h=u+p . v where u is the specific internal energy, p is the pressure, and v is specific volume. In other words, h = H / m where m is the mass of the system. The SI unit for specific enthalpy is joules per kilogram. [Wikipedia]

quantity:Enthalpy
Property Value
qudt:description Static enthalpy per unit mass. The specific enthalpy of a working mass is a property of that mass used in thermodynamics, defined as h=u+p . v where u is the specific internal energy, p is the pressure, and v is specific volume. In other words, h = H / m where m is the mass of the system. The SI unit for specific enthalpy is joules per kilogram. [Wikipedia]
qudt:generalization quantity:EnergyAndWork

quantity:Heat: Heat

Energy transferred by a thermal process. Heat can be measured in terms of the dynamical units of energy, as the erg, joule, etc., or in terms of the amount of energy required to produce a definite thermal change in some substance, as, for example, the energy required per degree to raise the temperature of a unit mass of water at some temperature ( calorie, Btu).

quantity:Heat
Property Value
qudt:description Energy transferred by a thermal process. Heat can be measured in terms of the dynamical units of energy, as the erg, joule, etc., or in terms of the amount of energy required to produce a definite thermal change in some substance, as, for example, the energy required per degree to raise the temperature of a unit mass of water at some temperature ( calorie, Btu).
qudt:generalization quantity:ThermalEnergy

quantity:HeatCapacityRatio: Heat Capacity Ratio

The heat capacity ratio, or ratio of specific heats, is the ratio of the heat capacity at constant pressure (C_P) to heat capacity at constant volume (C_V). For an ideal gas, the heat capacity is constant with temperature (?). Accordingly we can express the enthalpy as H = C_P*? and the internal energy as U = C_V*?. Thus, it can also be said that the heat capacity ratio is the ratio between enthalpy and internal energy

quantity:HeatCapacityRatio
Property Value
qudt:description The heat capacity ratio, or ratio of specific heats, is the ratio of the heat capacity at constant pressure (C_P) to heat capacity at constant volume (C_V). For an ideal gas, the heat capacity is constant with temperature (?). Accordingly we can express the enthalpy as H = C_P*? and the internal energy as U = C_V*?. Thus, it can also be said that the heat capacity ratio is the ratio between enthalpy and internal energy
qudt:generalization quantity:DimensionlessRatio

quantity:LinearThermalExpansion: Linear Thermal Expansion

When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

quantity:LinearThermalExpansion
Property Value
qudt:description When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

quantity:ThermodynamicEntropy: Thermodynamic Entropy

Thermodynamic Entropy is a measure of the unavailability of a system’s energy to do work. It is a measure of the randomness of molecules in a system and is central to the second law of thermodynamics and the fundamental thermodynamic relation, which deal with physical processes and whether they occur spontaneously. Spontaneous changes, in isolated systems, occur with an increase in entropy. Spontaneous changes tend to smooth out differences in temperature, pressure, density, and chemical potential that may exist in a system, and entropy is thus a measure of how far this smoothing-out process has progressed. It can be seen that the dimensions of entropy are energy divided by temperature, which is the same as the dimensions of Boltzmann's constant (kB) and heat capacity. The SI unit of entropy is joule per kelvin. [Wikipedia]

quantity:ThermodynamicEntropy
Property Value
qudt:description Thermodynamic Entropy is a measure of the unavailability of a system’s energy to do work. It is a measure of the randomness of molecules in a system and is central to the second law of thermodynamics and the fundamental thermodynamic relation, which deal with physical processes and whether they occur spontaneously. Spontaneous changes, in isolated systems, occur with an increase in entropy. Spontaneous changes tend to smooth out differences in temperature, pressure, density, and chemical potential that may exist in a system, and entropy is thus a measure of how far this smoothing-out process has progressed. It can be seen that the dimensions of entropy are energy divided by temperature, which is the same as the dimensions of Boltzmann's constant (kB) and heat capacity. The SI unit of entropy is joule per kelvin. [Wikipedia]
qudt:generalization quantity:EnergyPerTemperature

quantity:VolumeThermalExpansion: Volume Thermal Expansion

When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

quantity:VolumeThermalExpansion
Property Value
qudt:description When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: * linear thermal expansion * area thermal expansion * volumetric thermal expansion These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications. Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]

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