Abstract
ISO 15926 is a series of standards for the integration of life cycle data
for process plants. The scope of the standards includes all life cycle phases
include conceptual and detailed design, procurement construction and
commissioning, and operation and maintenance.
The standards have a formal basis with a top-level ontology that uses a 4D
approach to change over times, and a possible worlds approach to design. The
ontology was defined initially using the EXPRESS information modelling language,
but a representation in OWL has been standardised as part 12 of the series. The
top-level ontology is used alongside a taxonomy of activities and physical
objects relevant to process plants and their properties.
During the design of a process plant the functional requirements for a facility
within the plant are defined, and then the type of equipment item to be
installed is selected for procurement. The validity of a select equipment item
for its intended duty can be validated automatically by inferencing engines. If
it is not valid, then the reason why can be reported.
The rendering of the 4D possible worlds approach in OWL DL to support
inferencing presents challenges, because using this approach much property and
design data involves relationships between user defined instances of classes.
The way in which this can be hidden from OWL to produce a useful and
computationally tractable view is discussed.
#### Auteurs/Autrices
**David Leal** has worked on formal representations of engineering data for many
years. He was a developer and user of finite element analysis systems, and
produced early representations of analysis data as relational data bases.
Subsequently he worked within ISO committee TC 184/SC4 “Industrial data” on
EXPRESS data models in international standards for engineering analysis data and
for life-cycle data for process plants. Recently he has been involved in
transforming the data models in these standards into OWL ontologies.