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QUDT Units Vocabulary (without dimensions) Version 1.1
The QUDT Units Vocabulary is an RDF/OWL specifications of common units of measure in the science and engineering domains. All SI Units are included. Links, where possible, have been made to dbpedia using 'skos:closeMatch' and 'skos:exactMatch'.
To provide a vocabulary of commonly used units. This comprises the SI and many non-SI Units.
The abampere (aA), also called the biot after Jean-Baptiste Biot, is the basic electromagnetic unit of electric current in the emu-cgs system of units (electromagnetic cgs). One abampere is equal to ten amperes in the SI system of units. [Wikipedia]
The abcoulomb (abC or aC) or electromagnetic unit of charge (emu of charge) is the basic physical unit of electric charge in the cgs-emu system of units. One abcoulomb is equal to ten coulombs. [Wikipedia]
An abfarad is an obsolete electromagnetic (CGS) unit of capacitance equal to 10^9 farads (1,000,000,000 F or 1 GF). This very large unit is used in medical terminology only. [Wikipedia]
The ångström or angstrom (symbol Å) (the latter spelling, without diacritics, is now usually used in English) (pronounced /ˈæŋstrəm/; Swedish: [ˈɔŋstrøm]) is an internationally recognized unit of length equal to 0.1 nanometre or 1×10−10 metres. It is named after Anders Jonas Ångström. Although accepted for use, it is not formally defined within the International System of Units(SI). (That article lists the units that are so defined.) The ångström is often used in the natural sciences to express the sizes of atoms, lengths of chemical bonds and the wavelengths of electromagnetic radiation, and in technology for the dimensions of parts of integrated circuits. It is also commonly used in structural biology. [Wikipedia]
The unified atomic mass unit (symbol: u) or dalton (symbol: Da) is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound atom of carbon-12 in its nuclear and electronic ground state,[1] and has a value of 1.660538782(83)×10−27 kg.[2] One Da is approximately equal to the mass of one proton or one neutron. The CIPM have categorised it as a "non-SI unit whose values in SI units must be obtained experimentally".[1] [Wikipedia]
Australia, Australian Antarctic Territory, Christmas Island, Cocos (Keeling) Islands, Heard and McDonald Islands, Kiribati, Nauru, Norfolk Island, Tuvalu
A ban is a logarithmic unit which measures information or entropy, based on base 10 logarithms and powers of 10, rather than the powers of 2 and base 2 logarithms which define the bit. One ban is approximately 3.32 (log_2 10) bits.
In information theory, a bit is the amount of information that, on average, can be stored in a discrete bit. It is thus the amount of information carried by a choice between two equally likely outcomes. One bit corresponds to about 0.693 nats (ln(2)), or 0.301 hartleys (log10(2)).
British Thermal Unit - International Steam Table
The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1 055.05585 joules. It is approximately the amount of energy needed to heat 1 pound (0.454 kg) of water from 39 °F (3.9 °C) to 40 °F (4.4 °C). The unit is most often used in the power, steam generation, heating and air conditioning industries. In scientific contexts the BTU has largely been replaced by the SI unit of energy, the joule, though it may be used as a measure of agricultural energy production (BTU/kg). It is still used unofficially in metric English-speaking countries (such as Canada), and remains the standard unit of classification for air conditioning units manufactured and sold in many non-English-speaking metric countries.
British Thermal Unit - Thermochemical Calorie
BTU Foot per Square Foot Hour Degree Fahrenheit
BTU Inch per Square Foot Hour Degree Fahrenheit
BTU Inch per Square Foot Second Degree Fahrenheit
The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1 055.05585 joules. It is approximately the amount of energy needed to heat 1 pound (0.454 kg) of water from 39 °F (3.9 °C) to 40 °F (4.4 °C). The unit is most often used in the power, steam generation, heating and air conditioning industries. In scientific contexts the BTU has largely been replaced by the SI unit of energy, the joule, though it may be used as a measure of agricultural energy production (BTU/kg). [Wikipedia]
BTU per Square Foot Hour Degree Fahrenheit
BTU per Square Foot Second Degree Fahrenheit
Benin, Burkina Faso, C�te d'Ivoire, Guinea-Bissau, Mali, Niger, Senegal, Togo
Cameroon, Central African Republic, Congo, Chad, Equatorial Guinea, Gabon
French Polynesia, New Caledonia, Wallis and Futuna
A dioptre, or diopter, is a unit of measurement of the optical power of a lens or curved mirror, which is equal to the reciprocal of the focal length measured in metres (that is, 1/metres). For example, a 3 dioptre lens brings parallel rays of light to focus at 1/3 metre. The same unit is also sometimes used for other reciprocals of distance, particularly radii of curvature and the vergence of optical beams. Though the diopter is based on the SI-metric system it has not been included in the standard so that there is no international name or abbreviation for this unit of measurement—within the international system of units this unit for optical power would need to be specified explicitly as the inverse metre. [Wikipedia]
Anguilla, Antigua and Barbuda, Dominica, Grenada, Montserrat, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines
European Composite Unit (EURCO) (Bonds market unit)
European Monetary Unit (E.M.U.-6) (Bonds market unit)
European Unit of Account 17 (E.U.A.-17) (Bonds market unit)
European Unit of Account 9 (E.U.A.-9) (Bonds market unit)
The fundamental unit of magnetomotive force (mmf) in electromagnetic units is called a Gilbert. It is the mmf which will produce a magnetic field strength of one Gauss (Maxwell per Square Centimeter) in a path one centimeter long.
Gold franc (special settlement currency)
the tangent of an angle of inclination multiplied by 100
A hartree (symbol E_h) is the atomic unit of energy. The hartree energy is equal to the absolute value of the electric potential energy of the hydrogen atom in its ground state.
Joule per Kilogram Kelvin per Cubic Meter
Calorie per Centimeter Second Degree Celsius
Kilocalorie per Square Centimeter Minute
Kilocalorie per Square Centimeter Second
A unit of length defining the distance, in meters, that light travels in a vacuum in one year.
Mexican Unidad de Inversion (UDI) (Funds code)
The Mil unit of plane angle, as defined by NATO to be 1/6400 of a circle.
The millimeter of mercury is defined as the pressure exerted at the base of a column of fluid exactly 1 mm high, when the density of the fluid is exactly 13.5951 g/cm3, at a place where the acceleration of gravity is exactly 9.80665 m/s^2.
Millimeters of Mercury inclusive of atmospheric pressure
A nat is a logarithmic unit of information or entropy, based on natural logarithms and powers of e, rather than the powers of 2 and base 2 logarithms which define the bit. The nat is the natural unit for information entropy. Physical systems of natural units which normalize Boltzmann's constant to 1 are effectively measuring thermodynamic entropy in nats.
Taiwan and other islands that are under the effective control of the Republic of China (ROC)
Cook Islands, New Zealand, Niue, Pitcairn, Tokelau
An ounce of mass is 1/16th of a pound of mass, based on the international standard definition of the pound as exactly 0.45359237 kg.
An obsolete unit of mass; the Troy Ounce is 1/12th of a Troy Pound. Based on the international definition of a Troy Pound as 5760 grains, the Troy Ounce is exactly 480 grains, or 0.0311034768 kg.
The parsec (parallax of one arcsecond; symbol: pc) is a unit of length, equal to just under 31 trillion (31×1012) kilometres (about 19 trillion miles), 206265 AU, or about 3.26 light-years. The parsec measurement unit is used in astronomy. It is defined as the length of the adjacent side of an imaginary right triangle in space. The two dimensions that specify this triangle are the parallax angle (defined as 1 arcsecond) and the opposite side (defined as 1 astronomical unit (AU), the distance from the Earth to the Sun). Given these two measurements, along with the rules of trigonometry, the length of the adjacent side (the parsec) can be found. [Wikipedia]
A pound of mass, based on the international standard definition of the pound as exactly 0.45359237 kg.
An obsolete unit of mass; the Troy Pound has been defined as exactly 5760 grains, or 0.3732417216 kg. A Troy Ounce is 1/12th of a Troy Pound.
The radian is the standard unit of angular measure, used in many areas of mathematics. It describes the plane angle subtended by a circular arc as the length of the arc divided by the radius of the arc. The unit was formerly a SI supplementary unit, but this category was abolished in 1995 and the radian is now considered a SI derived unit. The SI unit of solid angle measurement is the steradian. The radian is represented by the symbol "rad" or, more rarely, by the superscript c (for "circular measure"). For example, an angle of 1.2 radians would be written as "1.2 rad" or "1.2c" (the second symbol is often mistaken for a degree: "1.2°"). As the ratio of two lengths, the radian is a "pure number" that needs no unit symbol, and in mathematical writing the symbol "rad" is almost always omitted. In the absence of any symbol radians are assumed, and when degrees are meant the symbol ° is used. [Wikipedia]
The register ton is a unit of volume used for the cargo capacity of a ship, defined as 100 cubic feet (roughly 2.83 cubic metres).
A unit of distance equal to 5.5 yards (16 feet 6 inches).
The number of discrete samples of some thing per second.
Although the sievert has the same dimensions as the gray (i.e. joules per kilogram), it measures a different quantity. To avoid any risk of confusion between the absorbed dose and the equivalent dose, the corresponding special units, namely the gray instead of the joule per kilogram for absorbed dose and the sievert instead of the joule per kilogram for the dose equivalent, should be used.
Square Foot Hour Degree Fahrenheit per BTU
The steradian (symbol: sr) is the SI unit of solid angle. It is used to describe two-dimensional angular spans in three-dimensional space, analogous to the way in which the radian describes angles in a plane.
Atomic units (au or a.u.) form a system of natural units which is especially convenient for atomic physics calculations. There are two different kinds of atomic units, which one might name Hartree atomic units[1] and Rydberg atomic units, which differ in the choice of the unit of mass and charge. [Wikipedia]
The electrostatic system of units is a system of units used to measure electrical quantities of electric charge, current, and voltage, within the centimeter gram second (or "CGS") metric system of units. In electrostatic units, electrical charge is defined via the force it exerts on other charges.
Planck units are unique among systems of natural units, because they are not defined in terms of properties of any prototype, physical object, or even elementary particle. [Wikipedia]
American Samoa, British Indian Ocean Territory, Ecuador, El Salvador, Guam, Haiti, Marshall Islands, Micronesia, Northern Mariana Islands, Palau, Panama, Puerto Rico, East Timor, Turks and Caicos Islands, United States, Virgin Islands
United States Dollar (next day) (funds code)
United States Dollar (same day) (funds code)
A magnetic pole is a unit pole if it exerts a force of one dyne on another pole of equal strength at a distance of 1 cm. The strength of any given pole in cgs units is therefore numerically equal to the force in dynes which it exerts on a unit pole 1 cm away.
An explicit unit to say something has no units.
Heat flux density, irradiance, power density
A sidereal year is the time taken for Sun to return to the same position with respect to the stars of the celestial sphere.
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