Mechanics Quantity Kind
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

QUDT Quantity Ontology Version 1.1
uses non imported resource: creator
description: The 'Quantity' Ontology provides a schema for defining quantities. A quantity is a measure of an observable phenomenon, that, when associated with something, becomes a property of that thing; a particular object, event, or physical system. A quantity has meaning in the context of a measurement (i.e. the thing measured, the measured value, the accuracy of measurement, etc.) whereas the underlying quantity kind is independent of any particular measurement. Thus, length is a quantity kind while the height of a rocket is a specific quantity of length; its magnitude that may be expressed in meters, feet, inches, etc. Or, as stated at Wikipedia, in the language of measurement, quantities are quantifiable aspects of the world, such as time, distance, velocity, mass, momentum, energy, and weight, and units are used to describe their measure. Many of these quantities are related to each other by various physical laws, and as a result the units of some of the quantities can be expressed as products (or ratios) of powers of other units (e.g., momentum is mass times velocity and velocity is measured in distance divided by time).
last updated: $LastChangedDate: 2011-06-01 13:34:19 -0700 (Wed, 01 Jun 2011) $
creator: James E. Masters
uses non imported resource: contributor
contributor: Irene Polikoff
subject: Quantities, Units, and Dimensions
uses non imported resource: description
with attribution to: TopQuadrantAttribution
with attribution to: NASA-ARC-Attribution
uses non imported resource: subject
uses non imported resource: exactMatch
has catalog entry: QUDT-QUANTITY-SchemaCatalogEntry
uses non imported resource: title
version info: $Id: OSG_quantity-(v1.1).ttl 4988 2011-06-01 20:34:19Z RalphHodgson $
has aspect scope: Basic treatment of quantities and units. No dimensional treatment in this graph.
contributor: David Price
uses non imported resource: CC-SHAREALIKE 3PT0-US
date created: 2011-01-04T14:44:26
type: Ontology
has domain scope: Science, Medicine and Engineering
uses non imported resource: rights
rights: The QUDT Ontologies are issued under a Creative Commons Attribution Share Alike 3.0 United States License. Attribution should be made to NASA Ames Research Center and TopQuadrant, Inc.
version IRI: quantity
specificity: 1
label: Quantity Schema
contributor: Daniel Mekonnen
namespace prefix: quantity
revision number: 1.1
acronym: QUDT
uses non imported resource: closeMatch
contributor: Ralph Hodgson
has license type: CC-SHAREALIKE 3PT0-US
has role: SchemaGraph
uses non imported resource: author
intent: The intent of the QUDT Quantity Ontology is to specify an OWL schema for describing the attributes and fundamental relationships of quantities. A quantity is a kind of property which exists as a magnitude or multitude with a unit of measure. When a quantity is associated with some thing it becomes a property of that thing.
has discipline scope: All disciplines
imports: vaem
imports: dtype
imports: qudt

Continuum Mechanics Quantity Kind
subclass of: Mechanics Quantity Kind
type: Class

Radiology
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Electricity and Magnetism
subclass of: Quantity Kind
type: Class
type: QuantityKindCategory

Biology
subclass of: Quantity Kind
type: Class
type: QuantityKindCategory

Constant of Proportionality
description: Two quantities proportional if they vary in such a way that one of the quantities is a constant multiple of the other. The multiple is the constant of proportionality between the two quantities. Constants of proportionality may be dimensioned in some quantity systems and dimensionless in others. For example, in the SI system, the permittivity of a vacuum has the dimensions L^-3 M^-1 T^4 I^2 and is measured in Farads per Meter; in the CGS-EMU system it has dimensions L^-2T^2 and is measured in Abfarads per Centimeter; in the CGS-ESU system it is dimensionless. Constants of proportionality are important in the definition of systems of natural units, where units are chosen in order to make certain constants of proportionality dimensionless and equal to 1.
subclass of: Quantity
type: Class

Quantity Kind
description: A Quantity Kind is an aspect common to mutually comparable quantities.
subclass of: Restriction
  on property: generalization
  max cardinality: 1
subclass of: Restriction
  on property: generalization
  all values from: Quantity Kind
subclass of: EnumeratedValue
type: Class

Financial
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Communications
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Optics
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Chemistry quantity kind
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Quantity value
description: A quantity value expresses the numerical value of a quantity with respect to a chosen 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.
subclass of: Restriction
  on property: unit
  all values from: Unit
subclass of: Restriction
  on property: numericValue
  all values from: numericUnion
subclass of: Restriction
  on property: numericValue
  cardinality: 1
subclass of: Restriction
  on property: valueQuantity
  all values from: Quantity
subclass of: Restriction
  on property: relativeStandardUncertainty
  max cardinality: 1
subclass of: Restriction
  on property: standardUncertainty
  max cardinality: 1
subclass of: Restriction
  on property: standardUncertainty
  all values from: double
type: Class
subclass of: Thing
subclass of: Restriction
  on property: relativeStandardUncertainty
  all values from: double
subclass of: Restriction
  on property: valueQuantity
  max cardinality: 1
subclass of: Restriction
  on property: unit
  cardinality: 1

Physical Constant
description: A physical constant is a physical quantity that is generally believed to be both universal in nature and constant in time. It can be contrasted with a mathematical constant, which is a fixed numerical value but does not directly involve any physical measurement. There are many physical constants in science, some of the most widely recognized being the speed of light in vacuum c, Newton's gravitational constant G, Planck's constant h, the electric permittivity of free space ε0, and the elementary charge e. Physical constants can take many dimensional forms, or may be dimensionless depending on the system of quantities and units used.
subclass of: Quantity
type: Class

Thermodynamics
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Information
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Quantum Mechanics Quantity Kind
subclass of: Mechanics Quantity Kind
type: Class

Constant value
subclass of: Quantity value
type: Class

Fluid Dynamics Quantity Kind
subclass of: Continuum Mechanics Quantity Kind
type: Class

System of Quantity Kinds
type: Class
subclass of: Restriction
  on property: baseDimensionEnumeration
  all values from: Enumeration
subclass of: Restriction
  on property: baseDimensionEnumeration
  max cardinality: 1
subclass of: Restriction
  on property: systemQuantityKind
  min cardinality: 1
description: 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.
subclass of: Restriction
  on property: systemDimension
  all values from: Dimension
subclass of: Restriction
  on property: unitSystem
  all values from: SystemOfUnits
subclass of: Restriction
  on property: systemQuantityKind
  all values from: Quantity Kind
subclass of: Thing

Solid Mechanics Quantity Kind
subclass of: Continuum Mechanics Quantity Kind
type: Class

Space and Time
subclass of: Quantity Kind
type: QuantityKindCategory
type: Class

Atomic Physics
subclass of: Quantity Kind
type: QuantityKindCategory

Quantity type
description: A quantity type is an enumeration of units that are measures of the same quantity kind.
subclass of: Restriction
  on property: default
  all values from: Unit
subclass of: Restriction
  on property: elementKind
  all values from: Quantity Kind
subclass of: Restriction
  on property: element
  all values from: Unit
subclass of: Restriction
  on property: elementKind
  cardinality: 1
subclass of: Enumeration
type: Class

Photometry quantity kind
description: Photometry is the science of the measurement of light, in terms of its perceived brightness to the human eye. It is distinct from radiometry, which is the science of measurement of radiant energy (including light) in terms of absolute power.
subclass of: Optics
type: Class

Quantity
description: A quantity is the measurement of an observable property of a particular object, event, or physical system. A quantity is always associated with the context of measurement (i.e. the thing measured, the measured value, the accuracy of measurement, etc.) whereas the underlying quantity kind is independent of any particular measurement. Thus, length is a quantity kind while the height of a rocket is a specific quantity of length; its magnitude that may be expressed in meters, feet, inches, etc. Examples of physical quantities include physical constants, such as the speed of light in a vacuum, Planck's constant, the electric permittivity of free space, and the fine structure constant. Or, as stated at Wikipedia, in the language of measurement, quantities are quantifiable aspects of the world, such as time, distance, velocity, mass, momentum, energy, and weight, and units are used to describe their measure. Many of these quantities are related to each other by various physical laws, and as a result the units of some of the quantities can be expressed as products (or ratios) of powers of other units (e.g., momentum is mass times velocity and velocity is measured in distance divided by time). These relationships are discussed in dimensional analysis. Those that cannot be so expressed can be regarded as "fundamental" in this sense.
subclass of: Restriction
  on property: description
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subclass of: Restriction
  on property: quantityKind
  all values from: Quantity Kind
subclass of: Restriction
  on property: quantityValue
  all values from: Quantity value
  description: a reference to the dimension that quantifies the property
subclass of: Restriction
  on property: quantityValue
  min cardinality: 1
subclass of: Thing
type: Class

Radiometry quantity kind
description: Photometry is the field that studies the measurement of electromagnetic radiation, including visible light. Note that light is also measured using the techniques of photometry, which deal with brightness as perceived by the human eye, rather than absolute power.
subclass of: Optics
type: Class