川端 亮

Requirements analysis in systems development is an important phase to recognize what systems are needed. Petri Net is useful for analyzing the target system which includes collaboration tasks. However, it is difficult and troublesome to describe it from scratch even for software engineers. This paper clarifies methods for reusing Petri Nets described in the past to save the waste of describing them. In this paper, two methods are proposed as ways for the reuse of Petri Nets. One is the way that target diagrams are searched in terms of structure, and the other is that target diagrams are searched in terms of semantics. Finally, these methods are combined and implemented as a tool which is supported by a computer. This tool makes analysts easy to search the target diagram and modify it even if they do not understand the rules of describing Petri Net. In contrast, people who are not familiar with the tasks of the target system can find diagrams by using structural conditions for the search.

This paper shows the importance of introduction of domain ontology to systems analysis in order to represent domain-specific terminology effectively and proposes a method to construct and visualize the domain ontology. Common ontology in a domain and a related domain is systematized from the viewpoint of the Domain-Task and Domain-Term. Ontology of Domain Tasks (ODTasks) describes the procedure of the work according to the Case Grammar. Ontology of Domain Terms (ODTerms) describes the super-/sub conceptual relation of the term. This term is the element that exists in the specific domain. Our method uses the concept of the Commitment Network as a basic viewpoint for the organization of Ontology. The target system analyzed from the viewpoint of commission of task. Commitment Network facilitates to clarify the task in detail. For easily understanding and describing Ontology treated by this research, Diagram for ODTasks and ODTerms. The editor for ODTasks and ODTerms is also proposed.