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ETRTick
ETRTick
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aToDCount
An analog to digital count is a number produced by an analog-to-digital converter to measure a physical quantity. The measurement action counts the time for the measurement transducer to reach equilibrium.
A count represents a quantity kind that depends upon the analog process that is being measured. For this reason, the association between count and quantity kind should ideally not be fully specified in this ontology, but should wait until the time of describing a particular device. However, that specification may require additional syntax in a schema. The current strategy in this ontology is to leave the specification of quantity kind to the point of description of a device, and to expect the additional syntax in the schema that uses this concept. The alternative is to define a subclass of AToDCount for each quantity kind. The delayed specification of quantity kind may provide a model to simplify the definition of other units.
Typically, a count will be the basis for a conversion-based unit that converts the count into a physical quantity.
acousticPower
Acoustic power measures the energy of sound in matter.
amountOfMolecularSpeciesQK
The amount of a substance is correlated with the number of molecules of that substance that are present.
A
ampere
An ampere is one of the base units in the SI units of measure, corresonding to the quantity kind of electric current. It represents a coulomb of electrical charge flowing through a known cross section per time. The default interpretation of cross section is the cross section of a wire in an electrical circuit, perpendicular to the path of the wire. For current through other media, the cross section must be explained separately.
ampere-hour
3600.0
An ampere-hour is a measure of electric charge typically used to describe the capacity of an electric battery.
ampere-metre
A m
ampere meter
ampere-squareMetre
A m2
ampere metre squared
amperePerMetre
A/m
ampere per metre
amperePerSquareMetre
A/m2
ampere per square metre
ampere_Power1
1.0
-1.0
angleQK
Angle measures the arc separation of two rays at some standard radius from their common point of origin. There is a choice between two angles, each of which is the difference between a full revolution and the other.
1.0
angular rate
An angular rate is a measure of speed of rotation.
"
4.8481368E-6
arcsecond
An arcsecond is 1/3600 of a degree of angle.
"/s
arcsecond per second
1.0
area
Astronomical magnitude provides a logarithmic comparison of apparent magnitudes of stars and other visible objects.
astronomicalUnit
1.495978707E11
An astronomical unit is the nominal distance between Earth and Sun.
100000.0
bar
bar
A bar is approximately the same a the air pressure on Earth at sea level.
b
bit
A bit is a measure of information, uncertainty, or entropy.
bit_Power1
1.0
bitsPerSecond
bits per second
bps
candela
cd
A candela is the unit of luminous intensity in the international system of units.
capacitance
Capacitance is the amount of charge that can be stored in a capacitor per change in electrical potential across the input to the device.
coulomb
C
coulomb
coulombPerCubicMetre
C/m3
coulomb per cubic metre
coulombPerSquareMetre
C/m2
coulomb per square metre
1.0
cnt
count
A count is an integer that represents the number of individuals of the subject class.
cubic metre
m³/s
cubic metres per second
data rate
Data rate quantity kind is the rate of transfer of information per time.
day
86400.0
A day is the nominal time for the Earth to rotate from one noon to the next noon at the same geographic location.
debye
D
debye
20*log(x/2e-5Pa)
dB
decibel
A decibel is 10 times the base 10 logarithm of the ratio of a measured quantity to a reference quantity. The quantities are generally power or intensity. The reference quantity is often implicit in casual usage. In this ontology, the implicit form only refers to the sound pressure level reference near the threshold of human hearing, the sound of a mosquito flying three metres away. All other reference quantities must be stated in the name of the unit, such as dBW, in which the reference quantity is one Watt.
10log(x/1w)
dBW
decibel watt
A decibel watt is 10 times the base 10 logarithm of the ratio of a measured quantity to 1 watt.
0.017453293
degree
°
A degree of angle is 1/360 of one full rotation.
dynamicViscosityQK
electricChargeDensityQK
electric charge density
electricChargeQK
electric charge
1.0
electricConductancePerDistanceQK
electricConductanceQK
1.0
electric current density
Electric current density is the same as electric current, but normalized per cross section area through which the current flow.
electricCurrent
Electric current is a measure of the amount of electrical charge flowing through a known cross section per time. The default interpretation of cross section is the cross section of a wire in an electrical circuit, perpendicular to the path of the wire. For current through other media, the cross section must be explained separately.
electricCurrent_Power1
1.0
-1.0
electricDipoleMomentQK
electric dipole moment
electricDisplacementQK
electric displacement
electricPotentialGradientQK
An electric potential gradient can be used to estimate the chance of dielectric failure. This quantity kind is also known as electric field strength.
electrictPotentialQK
Electric potential measures the energy that would be gained by an electric charge moving from the point of measurement to the reference point, which has zero potential.
1.0
-1.0
electricResistanceQK
1.60217657E-19
eˉ
An electron is an elementary particle that carries an electric charge. The unit of electron is the measure of the charge of one electron.
1.0
electronsPerPixelPerSecond
eˉ/pixel·s
entropyQK
Entropy may also be called "heat capacity".
F
farad
A farad is the charge in Coulombs that a capacitor will accept for the potential across it to change by one volt.
F/m
faradPerMetre
forceQK
1.0
frameCountQK
A frame count represents the quantity of frames that have been imaged by a camera.
frequency
ω
Frequency measures the rate at which some implicitly defined event occurs. This ontology differentiates inverse seconds from frequency, because the former has no event associated with it.
H
henry
H/m
henryPerMetre
1.0
-1.0
Hz
hertz
Hertz is the frequency of 1 event per second. The event is not explicitly defined in the unit.
3600.0
An hour is one 24th of a day.
inductanceQK
1.0
informationQK
H
information
John von Neumann's advice to Claude Shannon about using the term "entropy" also carred the reason that "no one knows what entropy really is, so in a debate you will always have the advantage".
This quantity kind is also known as entropy. Claude Shannon is said to have considered calling it information or uncertainty, preferring the latter because the former seemed overused. John von Neumann advised calling it entropy, because it was already in use in statistical mechanics.
informationQK_Power1
1.0
1/H
inverseHenry
1/K
inverseKelvin
1/s
inverse second
J/K
joulePerKelvin
-1.0
kilogramMetreSquared
k·gm²
kilogramPerMetre
3.0
lengthQK_PowerMinus1
-1.0
lengthQK_PowerMinus2
-2.0
lengthQK_PowerMinus3
-3.0
0.001
L
litre
A litre is 1/1000 of a cubic metre.
0.001
L
litre
A litre is 1/1000 of a cubic metre.
luminosity per area
Luminance provides a measure of spectral flux density that is invariant along a light beam.
luminosityQK
Luminosity, or luminous intensity, measures the strength of electromagnetic radiation.
1.0
magneticDipoleMomentQK
magnetic dipole moment
magneticFieldStrengthQK
magneticFluxDensityQK
magnetic flux density
magneticFluxQK
1.0
magneticPoleStrengthQK
magnetic pole strength
1000000.0
M
mega
Mbps
megabitsPerSecond
m/s²
metre per second per second
3.0
metre_PowerMinus1
-1.0
metre_PowerMinus2
-2.0
metre_PowerMinus3
-3.0
0.001
m
milli
millisecond
ms
60.0
A minute is one 60th of an hour.
mol
mole
A mole is a base unit in the SI units of measure. It represents the quantity of a molecular species.
N·m
momentOfForce
N
newton
N·m
newtonMetre
N/m
newtonPerMetre
1.0
candela per square meter
cd/m^2
A nit is a measure of luminance, which is invariant along the propagation of a light beam. It is measured in candelas per square meter.
ohm
Ω
pascal
Pa
pascal
Pa·s
pascalSecond
1.0
%
percent
a percent is a ratio multiplied by 100
percentQK
%
percent
permeabilityQK
pixel
pixel
The pixel unit represents a count of 1 pixels.
pixelQK
The pixel quantity kind represents a count of pixels.
-1.0
1.0
pressureQK
force per area
1.0
quantityQK
The number of countable individuals of the subject class.
rad
radian
A radian is a natural measure of angle. It is the ratio of the length of the arc within the angle to the length of the radius of the arc. There are 2pi radians in a full rotation.
In SI units a radian would be unitless, because it is the ratio of two lengths. In this ontology it is treated as a fundamental concept, independent of interaction with length.
radians per second
A radian per second is an angular rate that rotates one radian each second of time.
1.0
second_Power1
1.0
S
siemens
S/m
siemensPerMetre
1.0
solidAngleQK
specificCapacitanceQK
square metre
6.75 - 2.5*log(x)
magnitude
stellar magnitude
Stellar magnitude provides a logarithmic scale for describing the brightness of stars in which the star Vega has magnitude zero, and dimmer stars have higher magnitudes.
sr
steradian
-1.0
surfaceTensionQK
T
tesla
-1.0
timeQK_Power1
1.0
torque
Torque has the same units as energy, which is a different quantity kind.
V
volt
A volt is the unit of energy gained by one coulomb of electrical charge moving from the point of measurement to the reference point, where the potential energy is zero.
V/m
voltPerMetre
1.0
-1.0
volumne
1.0
volumetric flow
Volumetric flow measures the rate of passage of incompressible fluid through a portal, or the rate of sweep of space by a moving scoop.
1.0
Wb
weber
Wb·m
weberMetre
Wb/m
weberPerMetre
Wb/m²
weberPerSquareMetre
A weber per square metre is also known as a tesla.
Wb/sr
weberPerSteradian
1.0
Energy is also known as work and quantity of heat.
Energy has the same units as torque, which is a different quantity kind.