Intending to design the vibration isolator systems or to identify the vibration systems, the impulse response for two-layered hyperbolic distributed parameter systems are derived from the transient analysis. By calculating the response waves of the two-layered systems, the relation between response waves and system parameters is considered. The validity of the impulse response for two-layered hyperbolic distributed parameter systems has been confirmed by the results of the actual two-layered systems. It is also shown from the digital simulation that more effective isolation of vibrations can be obtained from combination of the first layer parameters and that of second ones.

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Recently, a new design method of optimal servo systems, called “ILQ Method”, has been developed by applying the pole placement method. This paper treats its generalization for relaxation of a restriction imposed on the system in its original version. By a natural extension of the selection method of design parameters as well as the pole placement algorithm, the restriction can be relaxed significantly. Under a relaxed condition, the design parameters can be chosen so as to specify each output response in a certain class, and in addition, the optimal gain achieving such specified output responses can be expressed explicitly in terms of the system matrices and the design parameters. Some numerical examples are also illustrated to show the validity of the design method.

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Electroencephalogram (EEG) analysis is an important means of obtaining detailed information on the brain functions which CT (computed tomography) or angiography cannot provide. To help grasp the brain functions visually and intuitively in diagnosis and treatment planning of brain diseases, the computerized topographic EEG (or topographic EEG mapping), giving a two-dimensional image of EEG amplitude or frequency distribution on the entire scalp through the use of a computer, has recently been used. At present, several types of interpolation methods are available for the. interpolation process required by the topographic EEG mapping. However, very few reports have been published regarding the evaluation of the current interpolation method.
This paper attempts to evaluate four interpolation methods from the viewpoints of interpolation accuracy and computational speed through experiments using actual EEG data. The four methods studied here are : “two-dimensional sampling function” “linear interpolation”, “bicubic lofted surface” and “Coons' bilinear curved surface”. As a result, the interpolation by Coons' bilinear curved surface is found to be most accurate among the four methods. So it is considered to be optimum when a sufficient length of time is available for computation. Accuracy of the linear interpolation method is slightly inferior compared with that of the Coons' bilinear curved surface method, but this would pose no problems in practical use. Furthermore, computational speed of the linear interpolation method is the highest among the four, then the method is considered to be most suitable when interpolation results are needed whithin a short time.

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This paper is concerned with stabilization of modified repetitive control systems with a low-pass filter in the servocompensator. Since the modified repetitive control system is a retarded-type delay system, the finite. spectrum assignment method is applicable for stabilization of the systen. The necessary and sufficient condition for spectral controllability of the modified repetitive control system is presented. A scheme of stabilization by finite spectrum assignment is presented. Furthermore, this stabilization method is applied to repetitive control system for plant with delay.

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