This paper deals with experimental results for a cooling temperature control systems with an input time delay by using a joint design method of closed-loop identification and Internal model Control (IMC). The joint design method for systems with time delay have proposed. The results show that the closed-loop has good performance with easily parameter setting compared with ordinary PID control.

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The ability to describe a neural network depends greatly on the number of neurons. In this paper, we consider a method of obtaining an optimal neural network through a forgetting operation. It is shown that by using the proposed method, an optimum neural network can be constructed not only from neurons having large singular values of the coefficient matrix, but also from neurons having small singular values of the coefficient matrix.

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In this paper, we propose a new system identification method by using a genetic algorithm (GA) which has a hybrid structure. The hybrid structure means that a GA has 2 structures. One is the most popular chromosome type GA. That is, chromosomes have binary type genes. The other one is real coded GA. The former is used for determining a function type automatically. The latter is used for determining the coefficient of the function, time delay in the system and combination of the functions automatically. Finally, in order to show the effectiveness of the proposed method, computer simulations were done. Furthermore, in the computer simulations, 2-kinds of systems are identified. One is the hammer stain model. The other is a complex model. From these simulation results, the effectiveness of the proposed method is cleared.

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In this paper, we propose decision support systems (DSS) for dealing in the two indexes TOPIX & Nikkei-225 which utilize neural networks and genetic algorithms. In the proposed systems, the neural networks are utilized in order to make forecasts of the indexes four weeks in the future. Genetic algorithms are utilized in order to find effective ways of dealing. Several computer simulations have been carried out in order to compare the proposed DSS with the other approaches such as the DSS using traditional technical analysis and buy-and-hold method. These simulations confirm the effectiveness of the proposed DSS.

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In this paper, we propose a constitution method of game player agent that adopts a neural network as a state evaluation function for the game player, and evolves its weights and structure by Evolutionary Strategy (ES). In this method, we attempt to acquire better state evaluation function by evolving weights and structure simultaneously.

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This paper tries to recognize EMG signals by using neural networks. These EMG signals are classified into seven categories, such as neutral, up and down, right and left, wrist to inside and wrist to outside. The neural network learns FFT spectra to classify them. It is shown that our approach is effective to classify the EMG signals by means of computer simulations.

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In recent years, observation of a wide variety in the earth surface can be done by improvement of remote sensing technology. The purpose in this paper is to recognize a drift ice using synthetic aperture rader (SAR) images. The recognition of the drift ice is achieved by using neural networks (NN). The neural network applies two methods, a BP trained neural network and a Self-organizing map. Training data is image features extracted from SAR images. The number of methods of extracting the features are two, Fourier transform and high-order autocorrelation function (HACF). Furthermore, false color is given to a SAR image. Features are extracted from that imge and are recognized by the neural networks.

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This paper presents a method for image classification by neural networks that use characteristic data extracted from images. In order to extract characteristic data image pixels are divided by a clustering method on HSI 3-dimensional space and processed by labeling to select domains. The validity of this technique is verified by means of computer simulation.

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We have developed a food intake measuring system. This system measures food intake amount of each dish, which is put on the tray. Therefore, this system needs to extract dish image from the tray. In this paper, we propose neural network algorithm (the NN) for the dish extraction process. We expect the proposed method can extract dish image accurately, even if dish is over lapped partly each other. We develop the mechanism of dish extraction by the NN and simulate it by using real data to show its ability in practical use.

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Bidirectional Associative Memory (BAM) is a typical example of recurrent neural networks. Software implementation of BAM does not obtain sufficient speed in the operation. Therefore, hardware implementation, especially, FPGA implementation of BAM is very promising. Originally, the weights of BAM are calculated by patterns to be memorized. However, we adopt a recursive learning method via the simultaneous perturbation learning rule.

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We apply a neural network for the active noise control. Then, we use the simultaneous perturbation method as a learning rule of the neural network. This active noise control system does not require an estimation of the secondary-path. We observed that this system could reduce a 200Hz sinusoidal wave noise and a band-limited white noise.

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We conducted two experiments to analyze the influence of our social agent on interpersonal communication. In the first experiment, the agent supported cross-cultural communication. The agent’s behavior influenced people’s impressions of the agent and their conversation partners. In the second experiment, the agent tried to control human relations. The agent’s attitude influenced subjects’ sentiment toward the agent, and their relations.

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Situation Awareness (SA) is a key concept that is widely used to assess performance of human-artifact interaction. In this presentation, we discuss definition of TSA(Team Situation Awareness) to apply the notion of SA to cooperative team works and the underlying mechanism of TSA. Then we propose a new notion of TSA, which is reducible to mutual beliefs as well as individual SA in multi-layered structure. It defines the conditions, which need to be satisfied before team intention can be initiated. Finally, we develop the methodological framework of inferring TSA.

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This paper focuses on safety and security interfaces for emergency management of disaster. First, the problems in emergency management are investigated from the viewpoint of communication and human computer coordination. Then, we discuss on the necessary functions to realize interfaces to enhance safety and security, and propose three new types of human support systems for disaster management, the information filtering system with semi-structured messages, the group decision support system based on the trouble communication model, and the visual interface for real time decision making.

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Successful sales practices were experimentally examined by focusing on the interactions of salesperson with a client. Twenty superior and average salespeople watched a training video and indicated what they would have done in unsuccessful scenes. We found that successful practices strengthen the process whereby the client and salesperson collaborate to find goals to satisfy rather than exchanging needs and solutions.

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This paper addresses the aspect of human-agent interaction based on the classfication of problems. In design problems, a user expects an agent to stimulate his way-of-thinking, also in planning problems to execute complex procedures on behalf of a user and support decision-making. We evaluate various types of agents through experimental case study.

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This paper discusses teaching information understanding by an autonomous mobile robot. The authors have studied a system that has a function of input variable selection and rule extraction from data for the grounding of teaching information. The performance of acquired rules was often degraded in the new environment, and refinement of the rules became necessary. This paper discusses the refinement of the acquired rules. We call the refined rules “skill rules”. Through interactions with the new environment assisted by a human via the environment, the acquired rules are to be refined. Simulations are done to demonstrate the skill rule acquisition.

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Character agents were introduced to navigate users and to provoke the utterance in a community on the Internet. We had conducted the experiment to research the effectiveness of the character agents with respect to the affinity of a community, and found that the usefulness of the navigator would have relationship with the familiarity to the networked community.

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In this paper, instead of taking conventional artificial intelligence approaches for an interface agent, we propose a new designing method using the ecological approach, since we would like to stress the importance of the agent’s ability to create reciprocal relationships with the human user (i.e., a social ability), rather than its knowledgeable ability enclosed within the agent itself. We propose to use Brunswik’s Lens Model Analysis to model the agent’s meta-recognition mechanism. This is for measuring and quantifying sociality between the two decision-making agents (i.e., a human user and an interface agent). Based on this analysis, then, we designed an agent that can infer the coordination level with a particular human, identify his/her skill levels, and adjust the level of shared situation awareness with its human partner.

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Unit discharges and local field potentials (LFPs) were recorded simultaneously in primary auditory cortex (AI) of a guinea pig for cross-correlograms and cross correlation functions of LFPs were compared. From the results, the adequate periods of signals applied for cross correlation analysis were discussed. Consequently this application period must be selected correspondingly to temporally changing response periods.

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Using Bonhoeffer-van der Pol (BVP) equation extended to three variables, it is shown that this single neuron model can produce an extraordinarily slow oscillation through a Hopf bifurcation. The generation mechanism of such neuronal rhythm is analyzed from a viewpoint of a bifurcation theory.

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The automatic parameter identification method proposed by Doya et al. of the Hodgkin-Huxley-type equations is investigated in detail. An improved estimation method is proposed and it is shown that our method resolves the difficulties in estimating parameters of HH-type equations with complicated membrane potential waveforms such as a chaotic bursting and also much improves the parameter estimation (learning) speed.

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The present report introduce a method originally proposed by Collinds (1961) to analyze the potential field around a biological molecular particle having the non spherical hemisphere cap. The potential equation for the hemi spherical cap was expressed by Abel type integral equations. The solution was expressed by the series expansion of Legendre poly nomials. The expansion coefficient were determined by the continuous condition between the facing two boundaries. The inner and outer potential around the hemispherical cap was strongly influenced by the expansion angle and circumferential angles. The present method when extended will be available for computing the potential field around the transmitter approaching to the cellular receptor.

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This paper presents a Lyapunov function for power system considering with dynamics of induction machine characteristic by the state function method. In the composition process of proposed Lyapunov function, the slipping dynamic characteristic of the induction machine is implicitly expressed. As a result, the dynamic characteristic of induction machine becomes equivalent to a synchronous machine with the voltage adjustment mechanism.

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This paper is divided into two parts. In the first part, we establish a generalized Nyquist stability criterion to finite-dimensional linear continuous-time periodic systems by means of the 2-regularized determinant about the harmonic transfer operator, which is a Hilbert-Schmidt operator. The generalized Nyquist stability criterion can apply to most practical periodically time-varying continuous-time systems with standard assumptions about the system matrices.

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The paper is divided into two parts. In the second part, we consider the numerical implementation problem of the generalized Nyquist stability criterion of the first part [1] derived by means of the 2-regularized determinant about the harmonic return difference operators of finite-dimensional linear continuous-time periodic systems. Numerical implementation of this generalized Nyquist criterion is developed through the staircase truncation on the harmonic return difference operator. To illustrate the results of the second part, asymptotic stability of the lossy Mathieu differential equation is investigated.

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A novel method to measure two-component velocity profile simultaneously was developed by using the combined system of a CCD area image sensor (CAIS) and a multi-point LDV. The benefits of this method are shown by pursuing the compact and convenient over the system. Moreover, the results of some measurements such as the flow field behind the cylinder shows the reliability of the measurement for turbulence field. The basics techniques of this method are estabrished and the applicability for the measurement of flow field is shown.

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This paper presents the basic structure of the hydraulic Spool-in-Cylinder and its application on the 3 D.O.F rotational parallel link mechanism. Hydraulic Spool-in-Cylinder is an actuator, which is consisted of a hydraulic cylinder, a spool, a mechanical feedback mechanism and a stepping motor. The 3 D.O.F rotational parallel link mechanism is consisted of three Spool-in-Cylinder. We can simply realize the control of the high output hydraulic Spool-in-Cylinder by adjusting the input of stepping motor. The experiments display that the locomotion of the 3 D.O.F rotational parallel link mechanism can mimic the human wrist locomotion.

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When a care taker assists many handicapped people, the person sometimes feels backache because of holding up motion. Therefore, in order to heal the pain, some care takers attach a protection belt to lumbar part. However, since the compliance of the belt is constant, it is difficult to bend the waist to assist elderly people. In this paper, we propose a new type of actuator to apply to protection belt. The actuator has a structure that a sponge is covered with silicon rubber. Thus, it is possible to control stiffness of the actuator according to user’s posture. From some experimental results, the effectiveness of the actuator is clarified.

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The goal of this study is to develop a mechanical system that can display elastic characteristic of an object aiming at the application in the field of virtual reality. Pneumatic parallel manipulator is introduced as a driving mechanism, consequently, which brings capability of minute force displaying property owing to the air compressibility. Compliance control system without using force/moment sensor is constructed by introducing a disturbance observer and a compliance display scheme is proposed. The validity of the proposed scheme is verified experimentally.

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The construction of an ultrasonic gas flowmeter is difficult because the attenuation of ultrasonic waves and the effects of acoustic noises are considerably higher for a gas than for a liquid. The sound field of the proposed meter is stabilized by FM ultrasonic wave; however, the receiver eliminates the FM components. Therefore, the flow rate can be measured using a single frequeney signal. The flowmeter investigated in the present study yields near satisfactory performance.

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In recent years the water has been paid attention as a working fluid again, for the demand of the technology considering the global environmental problems. In this paper we compose the water hydraulic servo system by combining a servo valve and a hydraulic motor and we study the control performance of rotational angle. The problem in the system is the existence of unmodeled dynamics, e.g. large starting torque and friction force of water hydraulic servomotor, which cause the significant performance degradation. We composed the gain scheduled PID-controller that improves the large steady state error and overshoot. We are succeeding fairly in attenuating the steady state error of water hydraulic servomotor.

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In the flowing quantity instrumentation, it has been attracted various sensors using the technology of MEMS. A product excellent as for the cost performance came to be supplied by this situation. We thought it paid attention to the pitot type flow meter in the difference pressure type. In this time, we used these high performance pressure sensors and tried to measure the flow rate. In this repot, it introduces the measurement principle of this flow meter. And the basic characteristics of flow rate are confirmed through the experiments. In addition, some matters are considered based on these results, and the possibility of this meter is referred.

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A power assist chair helps the user to stand up. The force directly acts on the user and soft actuation is important. In this study, a virtual spring is proposed to realize the soft actuation. The seat is pushed up with a pneumatic cylinder so that assist force is controlled to be proportional to the seat angle. This leads to spring characteristics. Combination of a proportional pressure-reducing valve and a single rod cylinder is the key to realize the virtual spring characteristics. With its control, the seat behaves like a spring, and the spring constant and the pre-compression can be adjusted by the control.

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This paper clarifies the mechanism of the evolution of water vapor pressures in wet gas meter and shows expressions of compensation for water vapor pressures that we derived from our experimental approaches.

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The new project aims at establishing innovative science and technology by integrating two sciences in order to achieve our SSR society. First, human behaviors and their mental states will be analyzed quantitatively and systematically by the systems science. Then, the analyzed results will be applied in designing optimal systems and infrastructures and will be used in their operations. Finally, the systems and human science for the SSR society will be clearly established through these activities. The paper introduces three major research categories in the project.

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In this paper we try to extract various factors that prevent safety and security in our life. Then, we try to construct structural models among these factors using DEMATEL (Decision Making Trial and Evaluation Laboratory). For the purpose of analyzing priority among these factors we revised the DEMATEL and found effective factors to be resolved in order to realize future safe, secure and reliable (SSR) society.

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We consider a system controlled by a human operator. The system is modeled by a Petri net and its normal state is specified by a linear inequality on the set of reachable markings. Admissible behaviors of the operator are given by an invariance based control technique. We extend a failure diagnosis method proposed by Sampath et al. to the case that the system has self-recovery. We introduce a novel concept called weak diagnosability. We propose an error detector and show a condition for the system to be weakly diagnosable.

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In this paper we propose a new fault detection method for robust control systems. Our technique is based on the singular value analysis of system matrices which is intermittently updated by recursive subspace method. A threshold of system fault has been derived with respect to robust stability of the closed loop system independently of the measurement noise. The numerical examples demonstrate the validity of the proposed method.

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For creating safe, secure and reliable (SSR) society, a concept of human support system using humanoid robots is proposed; humanoid robots exist in our environment and protect us from dangers. A basic control method for humanoid robots of generating human support motion is developed. An evaluation system of human sense of security for coexisting robots is discussed.

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This paper proposes a method for finding and tracking people in input images which uses skin color information. Making color models for skin color and background enables us to find people easily and to track people without any discomfort. Our proposed method can track overlapped people by considering their mutual positions and textures. We use a omnidirectional image sensor for taking images in order to capture many people for a long time in this paper. We conduct experiments for evaluation of the proposed method.

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3-D Object motion tracking method without feature extraction is necessary for monitoring human action in an usual civil-life scene. To realize a fast and robust object tracking method, we propose a model-based method using intensity images. At first, the 3-D shape and reflectance of the object are measured by using a rangefinder constructed with a camera and projector. Then, several CG images with varied object pose and position are generated and then compared to the input image. The pose and position of the object are estimated by minimizing the residual of the CG and input images. We made a special CG generator which is a precise simulator of the real camera to generate a CG image identical to the input image. We confirmed the ability of our method and achieved a 3DOFs real-time object tracking system in 4.5frame/sec speed.

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We report our recent work about basic studies on crisis management systems for reliable communication/transportation network design and evacuation guidance of residents against large-scale disasters. First, we survey recent developments in modelling of evacuation problems. Next, we describe our efficient algorithm for evacuation and transportation network design to optimally locate facilities of safety.

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In case of emergency, we need to grasp the situation and make correct assessment quickly. The picture taken from monitoring camera is inportant information in the emergent situation. In our research, we attempt to build a support system for identifying the picture of the monitoring camera by dealing with the pictures as spatio-temporal data. We proposed a method, which displays those pictures on one virtual large wall. For this presentation, the search key in our system is the location and the size of this large screen and from which direction to look. First we developed a general algorithm to index spatio-temporal data to get an idea for developing the algorithm for this search key.

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The Driving Safety Support Systems (DSSS) is an intelligent system that can enhance safety in car traffics and prevent traffic accidents by coordinating a highly advanced traffic management system and intelligent vehicles. This system is one of important subsystems within the Universal Traffic Management System (UTMS) currently being developed by National Police Agency of Japan and Universal Traffic Management Society of Japan. The verification tests are almost finished now, and standard specifications for practical operation are being developed. This paper reports a series of DSSS research & development woks, as well as the future DSSS development plans.

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Presented and discussed in this paper are mathematical model used for expressing ship motions, application of Decoupling Control Methodology to construct the automatic control system and corresponding designing issues. Simulation results for a Very Large Crude Carriage in several harbor maneuvers under various strong environmental disturbances are given to illustrate the application and show excellent effectiveness of the system.

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This paper describes an Expression of Dynamical System Connection in Decentralized Autonomous Control for Complex Induction Motor Control Systems¹⁾. Decentralized autonomous system has several elements which conduct autonomously and interact among them to realize the desired total motion or to reduce the number of elements of the system mathematically. In the dynamical approach, it is preferable that the system connection changes according to the environmental condition. It is very useful for the new conditions corresponding to the new technological improvements both software and hardware ones in such an our daily complex system for Electro-Magnetic Interference (EMI) active filter which is considered. Thus, EMI active filter approximation is studied on new Triple-LISN circuit structure especially for CM currents that can suppress EMI noises in some extend in the motor drive system.

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An angular mometum control of a tumbling spacecraft by applying repetitive impulses from a space robot arm is discussed. By assuming inputs by the arm, the direction, size and timing of the input forces are relatively free to chose. At each control cycle, however, torques parallel to the contact direction cannot be generated. Therefore, the design of controller is not straightforward. To solve this defficulty, the equations of rotational motion are rewritten into simpler forms by applying appropriate coordinates transformation. Then a discrete controller is designed so that the component of the angular momentum parallel to the contact direction is damped out by choosing the directions of input forces property. Numerical simulations are given to show that the angular momentum is efficiently damped.

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This paper proposes a new digital redesign method for a linear state-feedback control system where the discretization of the closed-loop control input signal is carried out based on the principle of equivalent areas. The proposed method is applied to decoupled CCV flight control and simulated to assess its control performance. Simulation results are presented to reveal a potential problem in using this principle as is for digital control.

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We consider adaptive estimation of stability derivatives of aircrafts from flight data. An adaptive estimation scheme which utilizes multiple observers is applied. The multiple observers are designed for representative models derived by rewriting the state equation of the system. Under a certain condition, the output signal is described by output estimates generated by the multiple observers. Using this property, the estimates can be computed from input and output data.

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