Scalar quantity ORM diagram

This object-role modeling (ORM) diagram sample shows schema for scalar quantity. It was designed on the base of the Wikimedia Commons file: Schema for Scalar Quantity.gif. [commons.wikimedia.org/wiki/File:Schema_for_Scalar_Quantity.gif] "Scalar Quantities (Figure 2) are used throughout the model to specify numerical values. The Scalar Quantity concept modeled here allows several representations. The simplest is "quantity has a single numeric value and a measurement unit attribute'. Possible more complex representations include a single value with an uncertainty, or a minimum and maximum value with a specified default value to use if a single value representation is required. In all cases the Scalar Quantity has a specified unit of measurement attribute. Subtypes of Scalar Quantity in other Figures are identified by the use of QuantityID as the reference mode for a subtype entity." [pubs.usgs.gov/of/1999/of99-386/richard.html] The object-role model example "Scalar quantity ORM diagram" was designed using ConceptDraw PRO software extended with ORM Diagrams solution from Software Development area of ConceptDraw PRO Solution Park.