Kunio Hiyama

Structural way of thinking as applied to data structure

The authors report the result of a quantitative analysis of the data structure of a relatively early electronic switching system and its evolution. The evolutionary process is a kind of total quality control (TQC). On the basis of quantitative studies of the existing system, it has been found that the data memory area (static aspect) and the access frequency to data (dynamic aspect) obeys Paretos principle, i.e. a few vitals consume a major part of the memory space and the real-time consumption. These and other studies lead to a clearer data structure and control structure.<<ETX>>

A Microprocessor-Based Multi-loop Network System

A microprocessor-based multi-loop network system (MLNET) has been developed. MLNET has been designed to be a flexible and reliable low cost local network suitable for small systems. MLNET consists of many nodes and a number of communication loops, whose control is distributed all over the nodes to increase its reliability. This paper describes MLNET, emphasizing on details of its network topology, intra-loop transmission and inter-loop communication schemes, and its hardware and software.

The group‐noted state transition method applied to a PC management system

To improve software productivity, my colleagues and I pointed out in a previous paper that the state transition method is suitable as the functional description and implementation method. In that paper we proposed the distributed state transition method, which was derived from the model of distributed sequential machines and showed results obtained by applying it to an electronic switching system. In this paper, to enlarge the application range of the state transition method, I consider applying it to a PC management database system, and propose a new integrated design method derived from the single sequential machine model as being suitable. First I propose the “group-noted state transition method” by introducing the sequential machine model. Then I propose this design method as follows. Initially, the function of the outer world of the system is classified into several groups, and management jobs are then divided into the same number of groups corresponding to them. The database information can also be classified in the same way and can support the design of the database system. After that, the state transition description is defined from the input/output information to/from the groups of the outer world. Furthermore, the method of notation in which the status group is added to the status name is proposed by classifying statuses using the concept of the management cycle. I also propose a new method for designing the software structure in which state transition diagram information is stored in the database system by converting it to table format. Results clarify that it is possible to make an integrated management database system by using this state transition method. They also clarify how to make a more advanced system by cooperating with the workflow system.