﻿ gistUOM The gist Unit of Measure Ontology Created with e6Tools Graphical OWL Editor Fiirst term in a ratio unit of measure. (Distance in the ratio unit "speed"). Second unit in the ratio unit of measure (Duration (time) in "speed"). Which unit of measure are you using. All measures are in some uom, even if we don't know what it is initially used to convert from one unit of measure to another if they both have the same zero base. Note this is the conversion factor to multiply a unit by to get to the base. So the conversion factor for inch would be 0.0254. You divide by the convertToBase number to get from a base unit to another. Currencies are rounded to specified precision Used for tempreature conversion because Celicus and Fehrenheit have non zero zero bases. It's the kelvin temperature of zero in the other temperature scale Time, but not on time line. For instance one week, or seven days but not Jan 1, 2008 to Jan 7, 2008 (which is an interval). Intervals have durations but aren't durations. Units to measure passage of time, hours, days years. Two dimensional area A measure of distance which can either be distances over the earth, but could also be height, width, length, depth, girth etc. Units to measure linear distance such as feet and kilometers. Units of two dimensional area such as square inches and hectacres. A scalar value which is either measured, estimated or set as a refernece value. Magnitudes of the same dimenstional type ( ie duration or electric current) can be compared with a > or < operator, but can still have difference in their relationToTheWorld type (ie you can compare actuals to estimates or references as long as the dimension is the same). Units of weight, pounds, kilos etc. Magnitude of mass. Assumes near the earth's surface, so weight and mass are equivalent for our purposes. Three dimensional space or equivalent fluid measurement. Units of three dimensional volume (cubic inch) as well as fluid volume (ounces). Each unit has a base unit and a conversion factor to the base. The bases are from SI. Amount of a substance as counted molecules. It's here for completeness, if we bridge to an SI unit conversion ontology. It is unlikely a commercial system, with the possible exception of some involved in chemical research would use this. Note I left the disjointness with Count, Weight and Volume out as there is some ambiguity, at least in my mind as to whether they are mutually exclusive. Units of counting, especially each but also units such as dozens. Measures that involve countable amounts (eaches as well as cases, and the like) can be decimal Note: we did not make count disjoint will all the other magnitudes as there are some magnitudes that could conceivably be counted (say distance in rods, it's a bit of a stretch admittedly but shouldn't harm anything). This is a ratio class where the numerator and denominator are of the same unit of measure. This would have to be enforced as a SWRL rule. Note there are two conventions multiple by 100 or not (ie 50/100 could be .5 or 50) we are going with the .5 convention, despite the name, as it involves less additional conversion in its use. Ratio Units are composed of two units, a numerator and denominator (for instance miles/ hour) Conversion factor will not be on the ratios, but will be on the numerator and denominator (so there won't be a conversion factor from miles/hour to kilometers/sec, but there will be one to convert the miles to kilometers and the hours to second). Unlike other units of measure, temperatures have a different zero value and therefore need an offset for coversion (process is use the offset to get to Kelvin, convert to the degrees in new unit, then apply the new unit offset. It's a bit complex, but it is generalized this way and easier to add new units) Base of temperature is in Kelvin per SI to allow for all units to be expressed relative to a real (in this case absolute) zero. Voltage Units of electrical power (volt). Note that wattage, current and kilowatt hours are composed unts. Measure of light Measure of brightness (candles ). Units of money. Note this is the only unit whose conversion factors include time (ie the conversion rates change on a daily basis). Special type of magnitudde due to to way rounding is handled in math and temporal aspect of conversion 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000 1.000