This paper describes a new information storage system named VASS (Value Added Storage System) which is designed to manage uniformly various data stored in different type of information systems. The data managed in VASS are represented in uniform strucrure of single table with 5 columns, value, data-type, attribute, entity and period. VASS can manage not only conventional data, numerals, texts, tables, but also data of new type, images, voice, and videos. In spite of simple storage structure of VASS, it is very flexible to change information structure, i.e. and schema evolution with easy operations. VASS can accept data with various formats and expose data with various formats, i.e., we can use VASS as a data transformation system. VASS can also play a role of historical data management system because it manages data with valid period. It is useful for management of office documents, research documents, human affairs. VASS supports distributed data management.
This paper also discusses requirements for information sharing in network and the efficiency of VASS to attain them. Finally, overview of proto-type system of VASS is introduced.

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In order to realize cooperation among various persons, it is required to establish reliable communication among them. Workflow diagrams have been used to represent complicated process by decomposing it into small unit tasks and relationships among them. Conventional workflow diagrams are not sufficient to represent human cooperative work, since modification of job flow is frequently required due to some unexpected conditions. For example, a person has to finish urgent work for his family. IDEFO is develolped as diagrams which are easy to understand. To handle such dynamic nature, we propose a generalized IDEFO diagrams, which can be easily translated to programs for active databases. Workflow simulator is also developed in order to handle cases when unexpected condition occurs. The methods are applied to represent medical examinations and diagnoses in a typical middle-size hospital. Process workflow is dynamically modified due to the waiting time of patients and availability of physicians. In order to prove the correctness of the workflow simulator, we examined the model using typical hospital data. The results almost coincide with the real hospital cases and thus we can assume that the simulator works correctly. We can further show that the model can handle problems caused by modifying the workflow dynamically.

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The spot size of CRT determines the resolution of the system. To improve the spot size, we proposed the new system by externally applied magnetic field, which was generated by the windings on the deflection yoke. The numerical simulation showed that the magnification of the system can be improved by 20% on the 17"-valve screen corner. And also the dynamic voltage, which was applied to the electro-quadrupole lens in the electron gun was reduced to 50% of an ordinal CRT.

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To increase a transmission capacity of existing OPGW in future, a coherent optical fiber communication is effective but it needs a control of polarization state of optical signal. In OPGW, the polarization state may be possibly fluctuated by alternative current or lightning and it may be severer than any other environments. But the optical polarization characteristics of OPGW have not been clarified.
This paper describes the experimental results of transient states of optical polarization by large impulse current in OPGW (200m length). The impulse current is maximum 16kA at peak with 1×10μs rise and tail time. Polarization states are measured by a real time stokes analyzer with 10MHz band width. As a result, the maximum change of polarization state on Poincare sphere is about 70degrees and the rise time is about 12μs, which is much longer than the impulse current rise time of 1μs. It is found that the polarization rise time depends on the inductance of spiral current along twisted conductor elements of OPGW, which makes magnetic field along the fiber in OPGW as occurs Faraday effect.

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This study describes an analysis method for central apnea episodes of newborns during sleep. It is very important to predict the central sleep apnea episodes, which are considered to be one of the major causes of sudden infant death. The cross-correlation between respiration and RR interval time series obtained from newborns is calculated. Employing the cross-correlation, the displacement between respiration and RR interval time series before central sleep apnea episodes was much larger than the displacement in the stationary state. Furthermore, we studied whether the analysis of spectrum components in EEGs can be evaluated by swaying circadian oscillation rhythm. Therefore it was considered that the occurrence mechanism of central sleep apnea syndrome by analyzing the cross-correlation between respiration and RR interval time series, and by the spectrum components analysis on EEGs.

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The safety issue of time-varying magnetic fields on cardiac activity was experimentally investigated. Strong pulsed magnetic fields were applied to several canine hearts from the outside body with differnt stimulating coils. The effect of the magnetic field was the induction of premature contraction (pc) immediately after the magnetic field. The threshold strength S induducing pc was determined as a function of the duration D when S was the peak electric field at the heart and D was the one-cycle period of the damped sinusoidal pulse. The threshold is expresed by the equation S=Srh/{1-exp(-D/k)} where Srh is the rheobase of 30V/m and k is the time constant of 2ms.

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Magnetoencephalography was measured during the understanding of kana word and kanji word. Six health Japanese males participated in the measurements. The subjects were instructed to press the button when the visual stimuli was non-word. T-statistical analysis revealed kana word had bigger magnetic responses than kanji word in the left temporal area at 300-340ms. The results indicate this area is important for kana word understanding. The equivalent current dipole was estimated this region. The dipole estimated around the left superior temporal sulcus. We conclude that the action in the left temporal lobe at the 300-340ms is related to phoneme process.

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Erbium-doped fiber amplifiers (EDFA) for use in bidirectional optical transmission systems requiring no or only a single repeater amplifier are investigated. Signal directions are discriminated by using two wavelengths: 1.535μm and 1.55μm. The optical gain difference between the two wavelengths is compensated by a subsidiary erbium-doped fiber installed in the 1.55μm channel. Each EDFA for the terminal equipment is designed to serve both as a postamplifier and as a preamplifier. The repeater amplifier, consisting of a unidirectional EDFA and a bridge circuit, combines and then separates the opposite directional signals. The power buget margins for a bit error rate of 10^-9 at 2.488Gbit/s are 49dB for non-repeater transmission and more than 42dB at both sides of the repeater for one-repeater transmission.

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We constructed a range finder that has two cameras and a laser slit marker. The range finder is a binocular stereo vision system that resolves the stereo matching problem in stereo vision illuminating a target by the laser slit.
In binocular stereo systems, the geometrical relation between two cameras affects the precision so that a precise calibration is needed. In addition, the calibration should be easy and require only simple operations. We propose an acculate and easy binocular stereo calibration method.

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In this paper, a computing method of higer order derivatives of Universal Learning Network (U. L. N.) is derived by forward propagation, and U. L. N. is extended so that Multi branches from node to node may be built in U. L. N..
It has been shown by theoretically comparing backward propagation with forward propagation that forward propagation is preferable to backward propagation in computation time when higer order derivatives with respect to time-invariant parameters should be calculated.
It is also suggested that robust control or chaotic control can be realized if higer order derivatives are available.

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A Hopfield network with self-feedbacks for the travelling salesman problem(TSP) is proposed. However, the self-feedback makes the network converge to a solution which is not feasible but has much information about the optimum solution. Therefore, in this paper, the influence of the self-feedback upon the solution is theoretically discussed and the method to improve feasibility by neuron outputs and activities is proposed.
Computational results on the TSP with 5_??_30 cities are reported, which show that the proposed method obtains higher performance than the conventional Hopfield method.

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In this paper we present a Dynamic Force Simulator (DFS) for force feedback in human-machine systems. We propose a virtual world model with two force flows: one is the force flow from human to an object, the other is the force flow from an object to human. To use this model, DFS simulates object dynamics, contact model and friction characteristics of the human hand interacting with the object in Virtual Reality. After derivation of kinematic and force relations between hand and object space, we balance the two forces: one from the human and the other from the object in the contact force space in Virtual World and then realize the adequate feedback forces to human operator. Interaction with DFS allows calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove we have developed. In this paper graping of a cylinder in the virtual world is presented During object grasping, we measure joint angles and torques using the sensor glove system. In the future we will use this system to analyze human dextrous manipulations called Human Skill.

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The purpose of this paper is to describe a method to constitute nonlinear control systems. First, homeomorphic mapping transforms the nonlinear systems in a rectangular co-ordinates into the linear systems in a curvilinear co-ordinates. Second, The control law is derived from the linear systems. Third, nonlinear control systems are constituted by the inverse mapping of the control law.

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To examine the possibility of electromagnetic precusor preceding an earthquake the vertical earth potential difference (EPD) has been observed continuously at an urban area. Iregularily continued pulses had been observed for several hours before and after the Off East Hokkaido earthquake. We have referred both a series of signals of the terrestrial magnetism and the lightning location (LLP) map. No significant signal is recognized on those of terrestrial magnetism, however, severe lightning flashes occured over the Japan Sea at this time. To clarify the cause of the EPD pulse signal, the LLP map and the radar echo map are shown in the case of (a) near lightning flashes (b) far lightning flashes (c) the Off East Hokkaido earthquake. The signals in the cases of (b) and (c) are similar, therefore, the pulses are detected by the far lightning electromagnetic change. The LLP map must be referred to examine electromagnetic precusors of an earthquake. The EPD signal generated by propagating seisamic wave is also recorded.

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