Possession of a property by a possible individual

5 Febr. 2012, 30 Jan. 2015


Introduction

In Part 2 a distinction is made between properties and indirect properties. The definitions given are:


Property

A Property is a ClassOfIndividual that is a member of a continuum of a ClassOfProperty. The Property may be quantified by mapping to a number on a scale.

NOTE 1 A member of a Property is a PossibleIndividual  that has the same degree or magnitude of the quality or characteristic represented by the Property as other members.

NOTE 2 The types of characteristic or quality, such as temperature or density, are instances of ClassOfProperty.

NOTE 3 Duplicate properties (e.g. that map to the same number on the same scale) should not be created within the same data store.

EXAMPLE A particular degree of hotness can be represented as an instance of Property.

EXPRESS specification:

ENTITY property  

    SUBTYPE OF (class_of_individual);  

END_ENTITY;  

Note - A property is something that usually is measured and shown on a P&ID with the proper instrumentation.


IndirectProperty

An IndirectProperty is a Relationship between a Property and a PossibleIndividual. The nature of the IndirectProperty is defined by its classification by a ClassOfIndirectProperty. A property is indirect when it does not directly apply to the PossibleIndividual it applies to, but is derived from some process.

NOTE A property is indirect because it does not directly apply. There can only be one temperature that a thing has (at a time), so a Maximum Allowable Working Temperature is not its temperature, but an indirect property derived from doing some tests or calculations to determine its value (as opposed to it being a current measurement). This is what makes it indirect.

EXAMPLE A Maximum Allowable Working Pressure of 50 barg for V101 is specified by an IndirectProperty between the pressure of 50 barg and V101, classified by the ClassOfIndirectProperty Maximum Allowable Working Pressure.

EXPRESS specification:

ENTITY indirect_property  

    SUBTYPE OF (relationship);  

    possessor   :   possible_individual;  

    property     :   property;  

END_ENTITY;  

Attribute definitions:

    possessor   :   The PossibleIndividual that possesses the IndirectProperty.  

    property     :   The Property that is indirectly possessed by the PossibleIndividual.  

The model for a completely quantified property is given in a separate topic.


Model

A temporal part of myVessel #MPO-439112, identified #MPO-439112-20070814T174605Z,

  • is classified with an instance of Property 'Pressure'
  • that is related by an instance of PropertyQuantification
  • that is classified with an instance of Scale 'barg'
  • with an instance of RealNumber
  • that is represented by an instance of ExpressReal
  • that has the content '30.5'

myVessel has a pressure of 50 barg

Template

The representation in template format is as follows: