Issue 7982: initialValue attribute only exists for a ParameterType or ArgumentType (issues) Source: (, ) Nature: Severity: Summary: Resolution: Revised Text: Actions taken: Discussion: End of Annotations:===== m: webmaster@omg.org Date: 30 Sep 2004 06:03:56 -0400 To: Subject: Issue/Bug Report -------------------------------------------------------------------------------- Name: Simona Bernardi Company: Universita di Torino mailFrom: bernardi@di.unito.it Notification: No Specification: UML Profile for Modeling Quality of Service and Fault Tolerance Characteristics and Mechanisms Section: Section 8.2 FormalNumber: Ptc/2004-06-01 Version: Draft RevisionDate: 7/21/2004 Page: 10 Nature: Enhancement Severity: Significant HTTP User Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1) Description For performance/dependability analysis the models are usually stochastics. How to specify distributions ? The "statisticalQualifier" attribute associated to a <> attribute allows to declare that the type of value of the attribute is a distribution but not the "type of distribution". On the other hand, a syntax is not given for the specification of the type of distribution as well as, in general, for complex timing values. To illustrate a possible solution let us consider a system UML model in which we want to specify the service time for two resources COM and MEM as random variables distributed according to the uniform PdF and to the negative exponential PdF, respectively. The annotation has to be as simple as possible but at the same time detailed enough to be useful for the construction of a stochastic model.