Issue 18692: SysML: Unts and QualityKind (sysml-rtf) Source: Lockheed Martin (Mr. Michael Jesse Chonoles, michael_chonoles2(at)omg.org) Nature: Uncategorized Issue Severity: Summary: Currently, QuanttiyKind can only be part of 1 SystemOfQuantities. This seems wrong. For example, wouldn’t the amp and abamp, one is the SI unit and other being the emu-cgs unit of current, have the same quantity kind, current, but they might be in different SystemofQuantities. This exclusive association would prevent reusing existing definitions of Units & QuantityKinds for custom systems. Resolution: Revised Text: Actions taken: May 1, 2013: received issue Discussion: End of Annotations:===== m: "Chonoles, Michael J" To: "sysml-rtf@omg.org" , "issues@omg.org" Subject: issue against SysML: Unts and QualityKind Thread-Topic: issue against SysML: Unts and QualityKind Thread-Index: Ac5GblfgLazVb5I6TmS1Fo3vuCUZaA== Date: Wed, 1 May 2013 13:18:19 +0000 Accept-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [158.186.156.81] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.10.8626,1.0.431,0.0.0000 definitions=2013-05-01_04:2013-04-30,2013-05-01,1970-01-01 signatures=0 X-Virus-Scanned: amavisd-new at omg.org X-Brightmail-Tracker: AAAAAR16Wag= X-Brightmail-Tracker: AAAAAA== Currently, QuanttiyKind can only be part of 1 SystemOfQuantities. This seems wrong. For example, wouldn.t the amp and abamp, one is the SI unit and other being the emu-cgs unit of current, have the same quantity kind, current, but they might be in different SystemofQuantities. This exclusive association would prevent reusing existing definitions of Units & QuantityKinds for custom systems. Michael Jesse Chonoles Lockheed Martin From: "Bock, Conrad" To: "sysml-rtf@omg.org" Date: Mon, 3 Jun 2013 14:25:07 -0400 Subject: RE: SysML RTF telecon, June 3, notes Thread-Topic: SysML RTF telecon, June 3, notes Thread-Index: Ac5gh0UekBjgdLc6SMCBhK1W6/Nxsg== Accept-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US X-Virus-Scanned: amavisd-new at omg.org Primitive typers, We discussed how to address the association problem in 18692 (Units and QuantityKind, see http://www.omg.org/archives/sysml-rtf/msg03907.html). The resolution of this issue enables units and quantity kinds to be reused in multiple systems of units and quantities, respectively. This requires the primary quantity kind for units to depend on which system of units a unite is in (the same unit can be in multiple systems), which in turn would need a ternary association, something SysML does not support. The definition and original requirement for the primary quantity kinds is unclear however, so we decided to remove Unit::primaryQuantityKind, unless someone can suggest a reason to keep it. Nicolas will send out an update with this and other changes for the Ballot 6 draft. Conrad