Keiichi Katamine

A Case Study: Requirements Elicitation Processes throughout a Project

Requirements changes sometimes cause a project to fail. A lot of projects now follow incremental development processes so that new requirements and requirements changes can be incorporated as soon as possible.These processes are called integrated requirements processes which integrate requirements processes with other development processes. We have investigated the requirements processes of a project from beginning to end, both quantitatively and qualitatively. Our focus is to clarify the types of requirements based on the components contained within a certain portion of the software architecture. Each type reveals its typical requirements processes through its rationale. The case studied is a system to manage the orders and services of a restaurant. In this paper, we introduce the case and describe the types of requirements processes. Then we discuss the reasons why we could not elicit all the requirements in the early development processes.

Requirements Maturation Analysis by Accessibility and Stability

The success of any projects can be affected by requirements changes. We define requirements elicitation as the activity of adding, deleting, and modifying requirements. We here refer to the completion of requirements elicitation of a software component as requirements maturation. The requirements of the component will never be changed after 100% maturation. We introduce the requirements maturation efficiency (RME) in order to estimate the requirements maturation period for the component. The RME of the requirements represents how quickly the requirements of a component reach 100% maturation. The goal of this paper is to define a method of estimating the RME of each component. Since requirements analysts (RAs) elicit requirements by accessing requirement sources and stability is one of the characteristics of requirements, we can assume that the RME of a component must be derived from the accessibility of the requirements source and the stability of the requirements. We model accessibility as the number of information flows from the source of the requirements to the RA and model stability with the requirements maturation index (RMI). The results from multiple regression analysis for two cases indicate that RME can be derived by these two factors with a significant level of 5%. We also discuss a method by which to estimate the period for requirements maturation.

An analysis method with failure scenario matrix for specifying unexpected obstacles in embedded systems

This paper describes an analysis method with failure scenario matrix for specifying unexpected obstacles in order to improve the quality of embedded systems. Although embedded software has become increasingly large in scale and complexity, companies are requiring the software to be developed within shorter periods of time. Therefore, the quality of the software is bound to suffer. This problem is one of the most serious concerns in a coming age of ubiquitous embedded systems. In order to improve the quality, it is very important to specify the forbidden behavior of embedded systems. The forbidden behavior of unexpected obstacles is analyzed by using a matrix and scenarios. This paper provides a detailed description of the analysis method used, in particular the cause, phenomenon, and goal in the scenario, relating them to each other by using a matrix.

Enhancing the ESIM (Embedded Systems Improving Method) by Combining Information Flow Diagram with Analysis Matrix for Efficient Analysis of Unexpected Obstacles in Embedded Software

In order to improve the quality of embedded software, this paper proposes an enhancement to the ESIM (embedded systems improving method) by combining an IFD (information flow diagram) with an Analysis Matrix to analyze unexpected obstacles in the software. These obstacles are difficult to predict in the software specification. Recently, embedded systems have become larger and more complicated. Theoretically therefore, the development cycle of these systems should be longer. On the contrary, in practice the cycle has been shortened. This trend in industry has resulted in the oversight of unexpected obstacles, and consequently affected the quality of embedded software. In order to prevent the oversight of unexpected obstacles, we have already proposed two methods for requirements analysis: the ESIM using an Analysis Matrix and a method that uses an IFD. In order to improve the efficiency of unexpected obstacle analysis at reasonable cost, we now enhance the ESIM by combining an IFD with an Analysis Matrix. The enhancement is studied from the following three viewpoints. First, a conceptual model comprising both the Analysis Matrix and IFD is defined. Then, a requirements analysis procedure is proposed, that uses both the Analysis Matrix and IFD, and assigns each specific role to either an expert or non-expert engineer. Finally, to confirm the effectiveness of this enhancement, we carry out a description experiment using an IFD.

Translating Nondeterministic Functional Language Based on Attribute Grammars into Java

Knowledge-based systems are suitable for realizing advanced functions that require domain-specific expert knowledge, while knowledge representation languages and their supporting environments are essential for realizing such systems. Although Prolog is both useful and effective in this regard, the language interoperability with other implementation languages, such as Java, is often critical in practical application development. This paper describes the techniques for translating a knowledge representation language, a nondeterministic functional language based on attribute grammars, into Java. Translation is based on binarization and current techniques for Prolog to Java translation although the semantics are different from those of Prolog. A continuation unit is introduced to handle continuation efficiently, while variable and register management for backtracking is simplified by exploiting the single and unidirectional assignment features of variables. Experimental results for several benchmarks show that the code generated by the prototype translator is more than 25 times and 2 times faster than that of Prolog Cafe for nondeterministic programs and deterministic programs, respectively, and more than 2 times faster than B-Prolog for nondeterministic programs.

A suggestion for analysis of unexpected obstacles in embedded system

In order to improve the quality of embedded software by finding obstacles unanticipated by software specifications, this paper describes a requirement analysis method based on an Information Flow Diagram and experiments using this method, with discussion. Recently, embedded software has become more large-scale and complicated while the development cycle of the software has typically been shortened. This industry trend compromises the quality of embedded software. In order to improve the quality of the software, unexpected obstacles must be carefully analyzed in the specification and design phases. We propose a diagram-based analysis method to answer this need, and have performed an experiment using the analysis method with an actual product. The results of the experiment made it clear that 1) Novice engineers can construct an Information Flow Diagram under the lead of expert engineers; and 2) The methods by which experts lead novice engineers in the analysis of unexpected obstacles require further refinement.

Multi-threading inside prolog for knowledge-based enterprise applications

A knowledge-based system is suitable for realizing advanced functions that require domain-specific expert knowledge in enterprise-mission-critical information systems (enterprise applications). This paper describes a newly implemented multi-threaded Prolog system that evolves single-threaded Inside Prolog. It is intended as a means to apply a knowledge-based system written in Prolog to an enterprise application. It realizes a high degree of parallelism on an SMP system by minimizing mutual exclusion for scalability essential in enterprise use. Also briefly introduced is the knowledge processing server which is a framework for operating a knowledge-based system written in Prolog with an enterprise application. Experimental results indicated that on an SMP system the multi-threaded Prolog could achieve a high degree of parallelism while the server could obtain scalability. The application of the server to clinical decision support in a hospital information system also demonstrated that the multi-threaded Prolog and the server were sufficiently robust for use in an enterprise application.