Making rational policy decisions for complex problems typically requires model-based support for comprehensive analyses of relations between decisions and various measures of consequences resulting their implementations. The paper summarizes the lessons from applications of advanced modeling techniques to complex environmental problems, and outlines the Structured Modeling Technology, which has been developed for model-based decision-making support for such problems.

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Sensing and measurement provides interesting and essential problems of physical phenomena and man-made systems in real-worlds. This article describes various types of mathematical problems which we have encountered in developing the sensing and measurement technologies: 1) super resolution, 2) sound source localization, 3) self-similarity in sensors, 4) consistency in gradient measurements, and 5) collaborative calibration architecture.

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Electromagnetic flowmeters are applied to tomographic imaging of flow velocity field through the proper design of the magnetic field. This paper describes a new design of the 3-D field excitation with two sets of eight magnetic poles and of eight signal pick-up electrodes. From the simulation study under a laminar swirling flow, reconstruction of 3-D distribution has been achieved.

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The paper proposes an effective non-destructive inspection using an electromagnetic wave (radar) which detects the defects such as cracks or cavities in concrete structures and measures their accurate positions, and also thicknesses for cavities. This is achieved by a pattern matching between the actual reflected wave signal and the predicted one composed based on a signal propagation model.

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Motivated by atmospheric re-entry of aerospace vehicles, this paper is concerned with inverse analyses of highly dynamical heat flux. The analytical model is given by three dimensional heat diffusion equation with unknown boundary parameters. The computational methods for identifying heat flux are proposed using the idea of output least square problem. The proposed algorithm is successfully tested with experimental data.

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The aim of this paper is to investigate the design of robust load-frequency controller (both state feedback and output feedback cases) for interconnected power systems with circular pole constraints. The uncertainty is assumed to be norm-bound and appears in the system and input matrices. The necessary and sufficient conditions for the existence of desired controllers are reduced to LMI.

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We propose a method of designing good approximate 2-Ddegree-of-Freedom (2DOF) digital controller which makes a variation of the output voltage very small at a sudden change of resistive load. The good approximate 2DOF digital controller is actually implemented on a DSP and is connected to a DC-DC converter. Experimental studies demonstrate that this type digital controller can satisfy given specifications.

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This paper concerns an application of H infinity compensators which achieve stability for a plant with large changes in characteristics as well as adequate disturbance suppression and reference tracking properties. The simulation result shows how the H infinity compensator designed for the plant with large perturbations (100~300%) is somewhat similar to the conventional PI controller.

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This paper presents a global optimization algorithm using difference of multiconvex relaxation successively for parameterized LMI problems. The problem is formulated as a minimax problem. On branch and bound, the relaxation is performed iteratively to have a feasible solution of the parameterized LMI problem. Numerical examples for stability analysis and gain performance analysis of linear parameter varying systems are shown.

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This paper describes a new method for identification of nonlinear mechatronic servo system having small backlash. A pseudorandom M-sequence is applied to the system, and from the crosscorrelation function between the input and output we can obtain up to the third order Volterra kernels of the nonlinear system. The experimental results show wide applicability of this method.

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This paper presents the results on parameters identification of a full scale unmanned excavator vehicle arm. The comparison result shows that the Generalized Newton method is better in term of prediction accuracy and computational speed.

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This paper presents a novel method (NR) for identifying soil parameters during traversing of a tracked vehicle on unknown terrain and shows that NR method is better candidate.

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Threaded fastenings are a common assembly method, accounting for over a quarter of all assembly operations. A model based approach for monitoring screw fastenings and the proposed strategy is integrated with a mechatronics based approach for automating threaded assembly systems. A methodology is based-on Least-Square Method. It is shown with up-to four parameters required by the model can be estimated.

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In this paper we consider tracking problems of a magnetic levitation system. We derive a nonlinear model of a magnetic levitation system and show that this model is feedback linearizable. We then design tracking controllers using the output regulation theory for linear systems. We show by experimental results that the obtained controllers work well.

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In this paper, we propose a control method for two-link flexible manipulators using controlled Lagrangian method. First we separate the time-scale only using coordinate transformation. Then after completing the control laws for two Euler-lagrange subsystems of different time-scales, a composite controller is obtained. The experimental results are presented to show the effectiveness of this control design method.

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The paper is concerned with the digital redesign of an analog, nonlinear, state-feedback control system, such that the time-integrals of the analog and digital control inputs are approximately equal in the sense of the Principle of Equivalent Areas. Although stability is not guaranteed theoretically, simulation studies show that this approach yields controllers with better performances than other methods tested.

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This paper is concerned with discontinuous output feedback stabilization of nonholonomic systems in port-controlled Hamiltonian forms. First, in order to obtain a dynamic feedback, an integrator is added to the systems via generalized canonical transformations. Second, we will clarify equivalence between stability of a state feedback system and that of the corresponding output feedback system. An output feedback stabilization method for this system will be derived based on this equivalence. Furthermore, some numerical examples show the effectiveness of our technique.

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We proposed a new approach for the anti-sway control of container cranes. The container crane modeled as hybrid PDE-ODE system with flexible cable. The control objective is to suppress the transverse vibrations of the crane via boundary control. It is revealed that a time-varying control force and a suitable passive damping at the actuator can successfully suppress the transverse vibrations.

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This paper addresses the issue of adaptive position/force control of an uncertain constrained flexible joint robots based on singular perturbation approach, in which the fast variables and the slow variables are defined by combing the force and position signals. It relies on the feedback of joint state variables and avoids noisy joint torque feedbacks. The proposed approach achieves the position tracking and the boundedness of force errors for the constrained robot with weak joint flexibility.

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In this paper we study on the passivity of flexible master-slave manipulators(FMSM) with symmetric bilateral control. First, we derive dynamic equations of the FMSM by means of the Hamilton's principle. Second, we prove the passivity in the positioning operation. Finally, we also prove the passivity in the neighborhood of the desired state in the pushing operation to an environment.

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We discuss a force control problem for a constrained one-link flexible manipulator based on distributed parameter model. The proposed control law consists of feedback of bending moment at the root of the flexible manipulator and its derivative, which regulates simultaneously the force and the rotational angle of the motor without the angle and the force information. And it provides the asymptotic stability of the closed-loop system.

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Collaborative Virtual Environments (CVEs) are being developed to support work and education, yet, research for entertainment is getting popular. A qualitative research was conducted in Active Worlds (AW). Some of AW users are famous in the virtual world, which affects usage of the system.

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In this paper, we propose a technique for automatically generating a virtual human model for an interactive MR system. A technique is described for generating a compound human motion from a set of primitive motions obtained by a motion capture system. Connecting the primitive motions after having applied rotation and parallel transformation to them generates various compound human motions.

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Usability means that the shape of a design indicates its usage. In light of this concept, we introduced an intuitive key-less entry system using PAN (Personal Area Network) technology. When turning a door knob for the purpose of opening a door, the PAN sends an entry data through a human body. This reduces unnecessary action as well as entry time for door opening. To confirm the efficacy of this concept, we developed a simple demonstration circuit.

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This paper mentions the seven-card-stud poker playing system that considers opponent player’s playing style in order to make a decision whether to drop a game or not, how many points to bet and whether to take bluff strategy. This paper also mentions experiments in which the system plays poker games with human players and discusses the experimental results.

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In order to avoid traffic accidents, recent studies have examined how to quantitatively evaluate a driver’s decline of wakefulness or depth of fatigue. However, in most of these studies, heartbeat measurement, polygraphs, and eye-movement measurement were adopted as ways to gather bio-medical data. In this paper, a new unconstrained, non-invasive system to obtain heart rate was proposed.

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To image the local blood region embedded in a skin tissue, we propose a method using diffuse reflectance images at two isosbestic wavelengths of hemoglobin (420 and 585 nm). The possibility of the method was confirmed by experiments with skin tissue phantoms. A topographic image of veins was successfully reconstructed from diffuse reflectance images of in vivo human skin.

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By varying the right pump speed in a continuous flow artificial heart system connected to the cardiovascular system of a mature goat, the dynamic response of left atrial pressure was observed and conditions that resulted in atrial suction were simulated. The results may be used to design a new mock circulatory system and better control algorithms to prevent atrial suction.

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This paper proposes a novel technique called Route Optimization to reduce the overhead and enhance the performance of a mobile network. The proposed protocol is more efficient than the basic solution. It effectively reduce unnecessary large traveling route and overhead, thereby enhance performance. The comparative analysis for both protocols has been presented at the end of this paper.

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This paper describes a project for the design and implementation of a community security system using individually maintained home computers that are connected to the internet. In the initial stage of the project, a preliminary kit has been developed that consists of a commercial camera, free-software and an operation manual. The future prospects are also discussed.

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This paper provided a method to support traffic with industrial real-time applications over non-real-time LAN technology, without loss of generality to use common protocol suits like TCP/IP. In addition, real-time Ethernet communication can be extended with some support for real-time communication over a shared-medium topology, which does not require any modification to existing Ethernet hardware.

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In this paper, we deal with congestion control of one bottleneck type for TCP/AQM network systems. We prove the stability of the plant and give the Youla parametrization of the stabilizing controllers. With this result, a control performance problem of the queue length at the bottleneck link is considered.

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This paper proposes a path-planning algorithm for multi-head dispensers by heuristic algorithms to increase productivity in PCB assembly lines. We analyze the assembly sequence of dispenser and formulate it as an integer-programming problem. The TSP algorithms are then applied to the formulated problem to find the near-optimal solution. Simulation results are presented to verify the usefulness of the proposed scheme.

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This paper proposes the Vane Integrated Manufacture System (VIMS) based on STEP-NC, whose mathematical basis is the Vane Digital Model (VDM). Knot Factor Method (KFM) based on NURBS is put forward to acquire a precise VDM. The example shows that compared with the traditional methods, KFM is more simple and practical.

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We proposed an optimization method to reduce the assembly time of chip mounters. Feeder assignment and assembly sequence are determined considering the multiple feeder assignment. We present mathematical model for feeder assignment problem and assembly sequence problem. Then we propose optimization methods to solve each sub-problem. Simulation results are presented to verify the usefulness of the proposed method.

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The Gerber file is the vector-formatted drawing file for PCB manufacturing, which includes various symbols, figures and characters. In this paper, we newly propose the Gerber-character recognition system to recognize all of component names located in PCB. To improve the performance, we develop the multiple recognizers by neural networks and the verifier considering the structural features.

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This paper presents a crossword puzzle method using a valuable structure with a sequential flow by heterogeneous adaptive agents with tags in generating an emergent message structure, which have a refined semantic network in the distributed artificial intelligence field. The author shows a multi-elements complex message generation scheme and a conversion scheme from a public message to a secret message.

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A novel cooperative algorithm is proposed for homogeneous multi-agents transporting multiple objects concurrently. Cooperation information among agents exchanged by blackboard and point to point approach. Cooperative algorithm consists of task balance and agent-object sequences co-evolution. Simulation experiments that three agents transport eight objects were conducted to evaluate the presented approach. Results show that transportation task sequences can be optimized.

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A multi-robot scheme for victim search operations is proposed. In this scheme, numerous autonomous robots form a virtual network over a devastated closed space such that each robot works as a relatively localized landmark node. Every two adjacent nodes in the net operate so as to keep locating each other. The net expands employing artificial velocity potential generated by itself.

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For the demand of complex control systems in industry process, a general framework of agent-based distributed intelligent control systems is proposed, which combines the natural distribution of distributed control systems and the factitious hierarchy of intelligent control systems by taking agents as intelligent controllers. Finally, the framework is illustrated by a case study of digester process.

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The track-oriented MHT (Multiple Hypothesis Tracking) can achieve a high tracking accuracy, since up to present observed data are utilized. In this paper, a track-oriented MHT based multiple targets tracking program (MTTP) and the execution time of MTTP using our defined scenarios are shown. Additionally, results of the execution time are analyzed and optimization issues for high performance are discussed.

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A new sensor concept for developing a system that puts weight on privacy protection of a monitored person is proposed. The sensor based on this concept was implemented, and it applied to a chair. As a result, the chair that can make the damage small if the data detected by this chair are stolen and analyzed was developed.

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Knowledge-based systems have been widely utilized in the field of industrial applications. However, there are problems for knowledge-based systems in order to be utilized more widely. The objective of this study is to develop a knowledge-based system using unified modeling language (UML) in order to solve these problems.

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The theory of road traffic flow with flow disturbance was developed by means of t-s diagram theory. By applying the t-s diagram theory, traffic bottlenecks are generalized as a unified concept and flows in any cases including traffic congestions can be treated with simple formulae as functions of measurable parameters. The results are applicable to ease traffic flow control.

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A forward-propagation learning rule has been proposed to acquire neural inverse models. This rule can solve a credit assignment problem based on Newton-like method. In the current work, we discuss how to estimate the parameters of a multi-layered neural network based on the credit assignment. The suitability of the proposed estimation framework is confirmed by computer simulation.

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This article presents an efficient algorithm based on the Hopfield Neural Network to solve the minimum domination set problem. In order to help the network find a better solution, we give a new energy function. The results show that the algorithm can get better results than simulated annealing and the traditional Hopfield network for this problem.

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An algorithm for the minimum vertex cover problem based on HNN leaning is presented. The network phase performs gradient descent in state domain, and finds a set of states minimizing the HNN’s energy. When the HNN gets stuck, the learning phase is performed to fill up the local minimum valley by modifying parameter in gradient ascent direction of the energy

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In this paper, we develop a double feedback neural unit (DFNU) for generating impulse sequence. One of advantages of the DFNU is in its simple structure using only double feedback loops. Simulation results show that a wide range of firing patterns can be observed from a randomly coupled network consisting of DFNUs by changing a critical parameter of the network.

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In this study, we investigate the frequency of appearance of the phase patterns and clarify the effect of parameter deviations. From the simulation results, it is shown that some phase pattern can be seen easily and the others can hardly seen because of the deviations. Such phenomena can separate the preferred patterns from undesirable patterns and it is convenient for the use of the system as some kinds of neural networks.

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A microsensor with a picogram mass sensitivity has been developed using a harmonic vibration of microcantilever. The mass change of the adsorbed molecules on the cantilever was measured by the resonance frequency shift. We constructed a prototype vibrator sensor using a piezoresistive cantilever. As experimental results, a mass sensitivity of 0.32 pg/Hz was obtained from water molecular adsorption in air.

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