In a research field of network-based control systems (NBCSs), the time delay problem is one of the most significant is- sues. Efficient stabilization methods of time delayed control sys- tems enable NBCSs to be flexibly applied to many kinds of situa- tions. A novel time delay compensation method based on the con- cept of network disturbance (ND) and communication disturbance observer (CDOB) has been proposed. The compensation method has the same effectiveness as that of the Smith predictor. In addi- tion, since the method is simple and does not need time delay model or time delay measurement, it can be easily implemented to various applications. However, the design method has not been concerned so far. This paper therefore presents stability analysis and studies a practical design procedure of the time delayed control systems with CDOB. At first, the concept of ND is introduced and the validity of the time delay compensation method is described. Then an analysis about the effects of parameters in control systems on stability is conducted. Characteristics of the effects of parameters on stability come out. Then we study a practical design procedure of the time delayed control systems. The validity of the design procedure is val- idated by experimental results. In the experiment, we also verify the performance of the system in the case of time-varying delay. Finally, comparative study of the method to the Smith predictor is presented

A large-scale, prospective study of tardive dyskinesia (TD) was performed in 11 psychiatric facilities in Japan. A total of 1595 psychiatric patients were enrolled in this study in 1987. The progress of these patients, with the exception of 490 dropouts, has now been followed up to 1988. The prevalence of TD at study entry was 7.6%, the annual incidence rate was 3.7% and the annual remission rate was 28.7%. Newly developed TD patients tended to be older, to have undergone more psychosurgery, and to have had lower neuroleptic doses than the patients who had not developed TD, whereas no specific variable could be detected as a factor associated with remission of TD. The results suggest that the incidence of TD is lower in Japan than that in Europe and North America.

This paper presents stability analysis and a novel design method of time delayed control systems. The time delayed control systems are constructed based on a time delay compensation method using the concept of network disturbance and communication disturbance observer. At first, the effect of time delay in control systems is described briefly and the effectiveness of the time delay compensation method is presented. Then analysis about the effects of parameters in control systems on stability of the time delayed control systems is analyzed. The main part of this paper is proposal of a novel design method of time delayed control systems according to the analytical results. Simulation results verify the validity of analytical results and proposed design method. The results also demonstrate the effectiveness of the time delay compensation method using the concept of network disturbance and communication disturbance observer

This paper presents a new approach to tracking the moving target with mobile robot. T h e task is difficult since t h e mobile robot has nonholonomic constraint. Considering the constraint of motion of t h e mobile robot, it is thought t h a t planning trajectory which t h e robot can follow is indispensable for wheeled type mobile robot control. Thus, in this research, the new control method for tracking t h e moving target based on trajectory planning is proposed. T h e N U R B S Curve is used for trajectory planning. T h e continuity to second derivative a n d convex hull which are t h e characteristics of t h e N U R B S Curve is t h e t h e best for trajectory planning of t h e mobile robot. By this method, higher efficient tracking is realized. T h e validity of t h e proposed method is confirmed by simulations.

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