Noriaki Yoshiura

Using the Security Camera System Based on Individually Maintained Computers for Homeland Security: The e-JIKEI Network Project

We have already started a project for creating a community security structure spread worldwide that uses individually maintained home computers connected to the Internet. We call this project the e-JIKEI network project. JIKEI means Vigilante in Japanese. The basic concept of the project is that every individual person watches in and around his/her house using cheap cameras as his/her eyes, PC as his/her brain and Internet as his/her communication means by his/her own expense. In this paper, we discuss using the e-JIKEI project for construing homeland security infrastructure

Community security platform for individually maintained home computers: The Vigilante Network Project

This paper describes a project for developing a community security platform that uses individually maintained home computers. In the initial stage of the project, a preliminary system was developed, which consisted of a commercial camera, free-software and an operation manual. Using the preliminary system, an operational experiment has been conducted with the cooperation of private homes in the historic town of Kiryu. The first goal of the experiment was to verify the effectiveness of the concept for the prevention of crimes. Many other social and technical problems, such as the protection of privacy and the extension of the system nationwide, are also discussed. The purpose of the project is to recreate, in the present day, a mutual watch system which widely existed in ancient Japanese communities, but in a much more powerful and flexible form with the aid of computers and the internet. The future prospects are also discussed in detail.

Decision Procedures for Several Properties of Reactive System Specifications

Reactive systems, such as operating systems or elevator control systems, are systems that ideally never terminate and are intended to maintain some interaction with their environment. Temporal logic is one of the methods for formal specification descriptions of reactive systems. By describing the formal specifications of reactive systems we can check the consistency of the specifications and whether they contain defects. By using a synthesis algorithm we also obtain reactive system programs from the formal specifications and prevent programming bugs. Therefore, it is important to describe reactive system formal specifications to secure reactive system programs. However, it is difficult to describe realizable reactive system specifications and it is important to revise unrealizable reactive system specifications into realizable reactive system specifications. In previous research, three properties have been introduced into unrealizable reactive system specifications. By using these properties, we can acquire more detailed information about the cause of the defects of unrealizable reactive system specifications in the specification description process. In this paper, we propose decision procedures that judge whether a reactive system specification has these properties. We also prove the soundness and completeness of these procedures.

Finding the causes of unrealizability of reactive system formal specifications

Reactive systems are the systems that maintain some interaction with their environment. Temporal logic is one of the methods for formal specification descriptions of reactive systems. The formal specifications of reactive systems enables to check the consistency of the specifications and whether they contain defects. By using a synthesis algorithm we also obtain reactive system programs from the formal specifications and prevent programming bugs. Thus, it is important to describe reactive system formal specifications. However, it is difficult to describe realizable reactive system specifications and it is necessary to find the causes of unrealizable reactive system specifications. In previous research, three properties have been introduced into unrealizable reactive system specifications and we suppose that this classification gives the hists of finding the causes of unrealizability. In this paper we propose several heuristics of finding the causes of unrealizability of reactive system formal specifications. To find the causes, we use tableau methods and the classification of the reactive system specifications.

Evolution mechanism of reactive system programs

Reactive system, such as operating systems or elevator control systems, is a system which ideally never terminates and is intended to maintain some interaction with its environment. There are some researches of synthesis reactive system programs from specifications described in formal languages such as temporal logic. The synthesis methods proposed in these researches synthesize several reactive system programs from one specification. It becomes a problem how to choose a good reactive system program among several programs synthesized from one specification. However, which reactive system is good depends on the behaviors of the environment. That is, we can not decide which reactive system program is good until it interacts the environment. Thus, it is desirable that a reactive system program should evolve itself according to the behavior of the environment. In this paper, we propose an idea of reactive system program evolution.

Characteristic of crossover traffic in graphical representation of cellular networks

In this paper, we evaluate the communication performance of one-dimensional mobile cellular networks from the view point of the mobile nodes speed distributions with the simulation method changing the minimum and maximum speeds, the type of speed distributions and the type of holding time distributions. Simulation results are measured as total number of completed calls, mean holding time of completed calls and probability distribution of holding time of completed calls. We can observe the phenomenon that the total number of completed calls changes according to the type of holding time distributions when arrival rate increases in the heavy traffic situation.