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Integrating four-dimensional ontology and systems requirements modelling



Conrad E. Bock, Charles Galey


Ontology has many applications to engineering but is not easily taken up by engineers. For example, specifying products in space and time together (four dimensions) enables more reliable modelling and analysis, but this work is primarily ontological and not accessible to most engineers. This paper summarises an existing method for integrating ontology and engineering, then applies it to four-dimensional requirements modelling, extending prior results. Requirements in this paper are treated as desired effects of a system on its operating environment. These effects are often respecified in multiple designs and tools, leading to redundancy and potential inconsistency. This can be addressed with centralised models of operating environment developed in systems engineering languages. These languages can specify the structure of operating environments formally enough to specify desired effects (except for spatial aspects), but cannot do the same for desired behaviour of those environments, because behaviours typically specify actions taken by a system to achieve those effects. This paper proposes new engineering-accessible extensions to logical system modelling for specifying intended environmental effects, including spatial relationships, without committing to the actions taken to achieve them. The proposed model supports centralised specifications of required system effects on their operating environments, enabling efficient integration with design.
Journal of Engineering Design


Ontologies, systems engineering, four-dimensional, requirements


Bock, C. and Galey, C. (2019), Integrating four-dimensional ontology and systems requirements modelling, Journal of Engineering Design, [online], (Accessed May 20, 2024)


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Created July 18, 2019, Updated February 24, 2020