This paper introduces an ontology-based method for checking requirements specification. Requirements ontology is a knowledge structure that contains functional requirements (FR), attributes of FR and relations among FR. Requirements specification is compared with functional nodes in the requirements ontology, then rules are used to find errors in requirements. On the basis of the results, requirements team can ask questions to customers and correctly and efficiently revise requirements. To support this method, an ontology-based checking tool for verification of requirements has been developed. Finally, the requirements checking method is evaluated through an experiment.

A communication model and a computer assisted communication method are introduced. With this model incorrect communications between humans are explained and then a method to lead successful communications with computer is illustrated. This method improves qualities of communications and can be applied to co-operative works. On the basis of the communication method, we have been developing a co-operative visual software requirements definition method via network with a visual requirements language named VRDL. Our method will improve quality of software requirements specification (SRS).

A software requirements specification (SRS) is a document at the first phase of software development. Since it is difficult to make an accurate SRS at the beginning of software development, we propose a supporting method to detect and interpret the inconsistency of SRS. First, we classify and define the inconsistency of SRS. Next, we describe how to detect and interpret the inconsistency of SRS. We use the Requirements Frame Model to detect the inconsistency of SRS. We apply the Dempster and Shafer's theory to interpret the inconsistency of SRS. We illustrate our method with an example.

As expert system technology gains wider acceptance in digital system design, the need to build and maintain a large scale knowledge base will assume greater importance. However, how to build a correct and efficient rule base is even a hard part in the knowledge-based system development. In this paper, we develop FARHDL (Frame-And-Rule-based Hardware Description Language) to form a knowledge base. The FARHDL is simple but powerful to specify the hardware requirements and can be directly simulated by PROLOG. Through the knowledge base transformed from FARHDL, a formal method can be developed to design, implement, and validate the digital hardware systems. Furthermore, behavioral properties, anomaly properties, structural properties, and timing properties are applied to analyze the requirements specification. The purposes of those properties are used to detect explicit/implicit incorrect specification clauses and to capture some desired requirements, such as completeness and consistency. Finally, the analysis results can be a useful tool for finding obscure problems in tricky digital system designs and can also aid in the development of formal specifications.

Requirements engineering refers to activities of gathering and organizing customer requirements and system specifications, making explicit representations of them, and making sure that they are valid and accounted for during the course of the design lifecycle of software. One very popular software development practice is the incremental development practice. The incremental development refers to practices that allow a program, or similarly specifications, to be developed, validated, and delivered in stages. The incremental practice is characterized by its depth-first process where focuses are given to small parts of the system in sequence to fair amounts of detail. In this paper, we present a development and validation of specifications in such an incremental style using a tool called ASADAL, a comprehensive CASE tool for real-time systems. ASADAL supports incremental and hierarchical refinements of specifications using multiple representational constructs and the evolving incomplete specifications can be formally tested with respect to critical real time properties or be simulated to determine whether the specifications capture the intended system behavior. In particular, we highlight features of ASADAL's specification simulator, called ASADAL/SIM, that plays a critical role in the incremental validation and helps users gain insights into the validity of evolving specifications. Such features include the multiple and mixed level simulation, real-value simulation, presentation and analysis of simulation data, and variety of flexible simulation control schemes. We illustrate the overall process using an example of an incremental specification development of an elevator control system.

In this paper we propose a method for generating Prolog program code and skeleton C code from a specification of requirements written in DFDs (Data Flow Diagram) and DD (Data Dictionary). This generation of code takes two transformation steps. The specification is transformed into a Prolog program and the transformed Prolog is used for generating skeleton C code so that the specification is directly expendable in the conventional programming environment. This work makes it possible to rapidly have a prototype by executing Prolog programs and remove the design stage from the software development life cycle. This has been implemented on UNIX workstation environment with a data flow diagram editor START system.