Today (Feb 23, 2012), I was asked by a customer about the way to add SI prefixes to a unit. My customer knows that it is possible to create a new unit, but he or she does not know how to include the information that the new unit is related to the references unit with some multiplier. I wondered that I have not seen the information about using the QUDV library in any of my SysML books. It seem to be a missing part of them. So, I decided to write this article by hoping that it will help other SysML users to gain more understanding about such library. The SysML v1.2 Specification [1] has provided the information about quantities, units, dimension and value types in Annex C.5. However, the specification does not provide any examples about using the prefixed unit and other conversion based unit sub-types. This article will show the way to create a prefixed unit which has information about its reference unit and the multiplier. Figure 1 -- QUDV model of Units and QuantityKinds A
SysML user group in Thailand is non-profit, independent, member-run organizations that provide an open forum to promote information exchange between SysML expert and a practicing systems engineer. They also learn from their shared knowledge and experiences with the use of SysML language and enabling methods/tools.