Kunihiko Hiraishi Professor
School of Information Science（Department of Information Science・Theoretical Information Science）

■Degrees

B.E., M.E. and Ph.D.from Tokyo Institute of Technology (1983,1985,1990)

■Professional Career

Fujitsu Laboratories LTD (1985)

■Specialties

Formal modeling and analysis of concurrent systems, discrete event systems, and hybrid systems

■Research Keywords

concurrent systems, discrete event systems, hybrid systems

■Research Interests

Modeling and analysis of discrete event systems and hybrid systems
A discrete event system (DES) is a dynamic system such that the state of the system changes only at discrete instances of time instead of continuously. DESs arise in the domains of manufacturing, robotics, vehicular traffic, logistics, and computer and communication networks. We are studying modeling and analysis of DESs by means of various kinds of formal models, such as automata-based models, graph models, algebraic models, and logical models. We are also interested in hybrid systems, which are systems with both continuous dynamics and discrete dynamics.
Efficient analysis and verification of concurrent systems
In the analysis of concurrent systems, there are several problems that do not happen in sequential systems. For example, the size of the state space often increases exponentially in the size of the model. This phenomenon is called state space explosion and it makes the analysis very difficult. We are studying efficient analysis and verification techniques for such systems.
Modeling of complex processes in nursing and cargiving services
In 2010, JST/RISTEX in Japan started a new R&D program ``Service Science, Solutions and Foundation Integrated Research Program''. "Innovation for Service Space Communication by Voice Tweets in Nursing and Caring" is one of the selected projects by the above program. The aim of the project is to develop a stress-free information assisting system based on smart voice messaging. By providing voice messaging environment optimized for current situation of nurses, the system helps nurses in their cooperation, knowledge sharing, and making work records, and as a result the system reduces various kinds of stresses associated with their work. To estimate current situation of nurses, it is important to have detailed process models that described working schedules and how they behave in various situations. Moreover, computer simulation based on the process models is useful for quantitative evaluation of the system. In this article, we first clarify problems to be solved toward the modeling of nursing and caregiving processes, and give solutions to them.

■Publications

■Extramural Activities