This paper reports on design of sequential software, which is one level higher than usual non-sequential software. The technical principle is a Finite State Machine model, while the humanistic principle is “Human intentional activity” based on natural language. The structure is a hierarchically expanding network of small FSM's, each of which has around three states, driven by an event driven OS. It features easy design, small software, high quality and short development period.

Current software engineering assumes that software is developed to meet the requirements of clients. Apart for this business model, there has been another and more universal business model. Namely, a person or a company develops their own commercial product/service of pure software or combined software and hardware, delivers it to a free and competing market and receives the revenue. Major systems vendors, big software vendors and embedded system vendors have been working with this business model. This paper explains the activities in the creation phase of the product or service, management requirements and development work in the new business model.

This reports an in-house development of an enterprise system, directed by top management. The background is explained, and it starts from the corporate-wide business model. This top down approach is better fitted than usual bottom up approach. Various backgrounds supporting this are explained.

This design method stands upon three bases. The first is to use a finite state machine (FSM) model of around three states, where the design is very easy. The second is to use an event driven OS, which enables direct execution from the specification level to the final implementation model. The third is the hierarchical architecture of the above-mentioned FSM's, which minimizes the software size. This method features high productivity and high quality. Although it is a development for embedded systems, it may be applicable to any systems as an ultimate design method.

The paper reports on results of a study aiming at establishing a fundamental basis for automating design of any kind of software. Considering the final object, an automatic design learning human designer has been taken. An excellent software organization with high maturity has been taken as the expert, and the hierarchical work process is the knowledge model. For detailing, the major operations are made by hierarchical detailing. Namely, a software design may be reduced hierarchically to various design rules, which are parent and children relationship of a human concept created during expansion of a piece of design to more detailed form. To know the inside of human mental operations generating a design rule, a more detailed study was made and it was found that a design rule may be further reduced hierarchically to some fundamental human mental operations, called micro design rules. They represent basic operations during a design. After reporting them, a discussion on further lower level structure used during them, which are dictionary type definitions is made.

Some major structures for improving the quality of software are described. It is noted that defects in software are the result of imperfections in the development process and that high quality is achieved through aiming for a better process. Structures are introduced in the product structure, the product architecture, and the work processes. As people constitute an essential part of the process, the human error problem and work time constancy are considered. Based on these, structures and general principles for improving quality are explained. Progress is attained by education in the broad sense. The present work is written for managers in software fields.>

Reports on the quality improvement activities of a Japanese telecommunication manufacturer, focusing on feedback from the field. The authors discuss actions taken when a problem occurs for the particular case of a maintenance system for communication products; the inservice quality improvement committee; and preventive actions. The importance of preventing the design error from occurring again is stressed.>