A plant model is necessary to design a controller. In conventional identification methods, the experience is required in order to obtain the reliable identification results, since the identification results differ by the sampling period. In this paper, a new real-time identification method on physical parameters is proposed. In order to realize a real-time identification, a simple adaptive control method that is noticed with high practical applicability and a delta form are unified. Furthermore, the effectiveness of the proposed method is verified by simulations.

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This paper proposes an efficient calculation method of the control law for nonlinear MPC. The proposed approach searches an optimal step-type input signal for a given performance index beforehand, then the input signal is successively updated using a continuation method. Hence, it can reduce the computation load because the number of the parameter to be optimized becomes one in the SISO case or the number of the inputs in the MIMO case, and solving TP-BVP can be avoided by a continuation method. In addition, the accuracy of the nonlinear algebraic equation, which gives the optimal condition, keeps well by analytically deriving the updating law of the MPC control law.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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This paper proposes an improvement method of control performance based on workspace observer for motion control of multi-degrees-of-freedom manipulator. It is theoretically confirmed that the equivalent mass in workspace may be fluctuant due to the posture change of the manipulator. Then, it is experimentally shown that the motion control performance would be improved, if the estimated equivalent mass from kinematics is utilized both to the nominal equivalent mass in workspace observer and the nominal equivalent mass for the force reference generation.

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Disturbance observer is a well-known technique for disturbance estimation and compensation. The disturbance observer has been widely employed in force control applications. However, practically, the exist of friction phenomenon can affect the performance of the force control system. This paper proposes a force sensing method considering friction reduction to achieve an efficient force control. A periodic signal is inserted in the control system for friction compensation. A high-order disturbance observer is designed for force sensing operation and canceling the effect of oscillatory disturbance that is not addressed by conventional disturbance observer. All of the control algorithm is implemented in FPGA. The experimental results verify the effectiveness of the proposed method.

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[in Japanese]

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This paper proposes a high-speed and high-availability contact motion control method. In the proposed method, first-order disturbance observer estimates external torque at each joints. Moreover, the jerk signal achieves rapid sensing for contact phenomenon. Validity of the proposed method is confirmed by simulation study. The simulation uses real parameters identified to the three degrees of freedom robot.

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[in Japanese]

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As motion control has advanced in the past decade, many algorithms, for examples, disturbance observer (DOB), load side disturbance observer (LDOB) and state observer (STOB) have been designed for observing the sense of external force. In this paper, a novel multi-encoder-based disturbance observer (MEDOB) is proposed for estimating the external force at the load side of flexible robot. By using the proposed observer, it is not necessary to estimate the spring coefficient parameters. Compared to the other conventional ways, the proposed observer based on multi-encoder system offers the advantages of faster response, and high accuracy. This algorithm is verified through the simulation results of multi-mass robot system.

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[in Japanese]

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In conventional research on reproducing thermal sensation using Peltier device, temperature or heat flow is controlled. However, the thermal impedance control is important, since the contacted objects exchange heat according to the impedance. This study constructs thermal impedance control system of Peltier device, by applying the structure of disturbance observer to the field of thermal control.

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This paper studies effects of model errors on stability of time-delay systems with communication disturbance observer (CDOB). We have proposed a time-delay compensation method based on network disturbance (ND) concept and CDOB and have applied to various cases of time-delay systems. Since it does not need time-delay models for implementation, it effectively works in case that time-delay value is unknown or time-delay models are unavailable. As for the robustness, deterioration of the steady-state characteristics due to the system model errors has been pointed out so far. This paper focuses on the effects of the system model errors on stability. The effects are analyzed based on poles calculation by using Pade approximation and the analytical results are verified by simulation studies.

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With the problem of environmental pollution and energy depletion in recent years, a control technology which improves the performance of automobile engine has been demanded. This paper presents a method for construction of response surface model and a control parameter optimization method for automobile diesel engine in order to develop a model-based control system and the early development technique based on the model. The proposed method for construction of response surface model is able to efficiently-develop the response surface model that describes the multiple control parameters in relation to the characteristic value such as fuel consumption and emission. The proposed control parameter optimization method is able to quickly and efficiently calculate optimal control parameters to optimize evaluation item such as fuel consumption and emission based on the model.

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[in Japanese]

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In-cylinder combustion heat release rate and air intake/exhaust valve property are important factors affecting diesel engine characteristics. This paper presents a diesel engine dynamics model based on the identification of these properties. A new approach is presented for describing the heat release rate based on the polynomial approximation which allows the simple identification of unknown parameters. Experimental and simulation study has been carried out to compare the engine speed and cylinder pressure at different external loads and nominal engine speed. The proposed approach exhibits good overall agreement of simulation results with the experimental ones in not only the engine speed but also the in-cylinder pressure at various operating conditions.

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[in Japanese]

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Emission characteristic of a diesel engine was investigated in consideration of model predictive control (MPC), engine which is of four-cylinder 2,982cc with a common rail system. The present MPC controls only main fuel injection duration and thus the emission characteristics may be deteriorated. Hence we suggest an improvement approach by parameters such as pilot injection.

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As an operation method of the temperature control system with resistive heaters that use the commercial power source, there is the zero-cross control scheme in that switches make or break at every zero-cross point of the AC line voltage. The zero-cross control scheme has the merit that the harmonic components of the current can be suppressed but has the weak point of a lower resolution. This study proposes a control technique for applying the delta-sigma modulation to zero-cross control to achieve a high resolution and a short delay time leaving the effect of the harmonic current component suppression and evaluate the performance of the control method.

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[in Japanese]

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[in Japanese]

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This paper proposes a method that extracts causal knowledge by using clue expressions. Our method decides whether a sentence includes causal knowledge or not when the method extracts it. Therefore, our method can extract causal knowledge accurately. Furthermore, the advantage of our decision method is to extract causal knowledge manually without dictionaries and patterns.

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Wikipedia is a huge encyclopedia which includes a lot of proper nouns. Wikipedia is used for many application tasks in the area of Natural Language Processing(NLP) . If these nouns would be available in an existing thesaurus, it would be very useful for NLP area. Therefore, we propose an automatic method for enhancing existing thesaurus by extracting knowledge from Wikipedia.

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We introduce a method of extracting causal information (e.g., Demand for semi conductor manufacturing equipments is good ) from Japanese financial articles concerning business performance of companies. Causal information is useful for investors in selecting companies to invest. Our method automatically extracts causal information as a form of causal expression by using statistical information and clue expressions. Moreover, we extract keywords from Web sites of companies and improve our previous method by using them.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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In this paper, we constructed trajectory measurement system of ultrasound probe scanning for analysis of skillful procedure in echography. The procedure measurement system was built using ARToolkit and a Kinect sensor, and accuracy verification of position measurement was performed. First, Probe position and posture for acquiring the basic cross-sectional imaging, the demand specification of a measurement system was determined. The measurement system which acquires a probe tip position by ARToolkit and acquires the form of an arm by Kinect sensor was built. Next, when procedure which traces a character for the purpose of acquisition of probe scanning procedure was measured, procedure measurement in accuracy sufficient about ARToolkit was able to be performed, but about the Kinect sensor, the subject remained in measurement of the Kanji character with many stroke counts. it became possible to trace on a body surface and to measure a scan trajectory by ARToolkit. The system is improved towards probe angle measurement from now on.

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[in Japanese]

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This paper describes a web application which supports TA(Teaching Assistant) check and score management of students in large classes. TA can input data and browse them very efficiently by using mobile devices which connect to the server through wireless LAN. The result of questionnaires for evaluating the system is reported.

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[in Japanese]

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[in Japanese]

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The paper propose new improved search and fit procedures for Active Shape Model (ASM). Both of these operations have been enhanced by using the Principal Component Analysis (PCA) effect on data reduction and object recognition. Paper investigates the new performance and shows the results gotten by new steps. Finally the results will be summarized in conclusion with referring to the positive and negative points of new procedures.

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[in Japanese]

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[in Japanese]

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3D Spectrum analyzer will be realized with quaternion signal representation and the extended fourier transform. And which may be suitable for observing of three axes signals. However, its huge calculating load bothers the designer at the implementation. Therefore, we mentioned a revolved design of the calculating module for DSC with the serial type algorithm.

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[in Japanese]

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This paper describes a method for stochastic localization of mobile wireless LAN client in multistory environment and sensor data fusion based on a state space model. In the multistory building, the signal strength of from the wireless LAN access point is unstable because of the reflection and the multipath fading of the signals. The estimation results are integrated based on the state space framework. In the paper, the moving the vertical floor in the building is detected from the estimation result of the localization. Experimental results show the feasibility of the method.

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[in Japanese]

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The need for disaster relief is increasing because of difficulties in forecasting and also the desire to improve the process, including management of disaster relief supply system. Lateral supply transshipments within supply system can be defined as stock movement between locations of relief inventory storage of the same echelon level. Interconnection between inventory storages can be assumed as network having self-supply capability where each storage able to redistribute their stock to neighboring storages to avoid stock out. This paper proposes proactive mutual supply network of periodic supply policy with dynamic time of shipment during disaster situation where demand and lead time information are greatly biased. This mutual supply networks can be regarded as an epidemic model in some restricted situations.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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A smart washer was proposed to detect the loosening without human involvement. The basic principle of how to detect bolt loosening is to the dynamics characteristics of a smart washer system which varies depending on bolt tightening axial tension. A method by supervisor with adaptive observer for bolt loosening diagnosis is proposed in this paper. The numerical simulations are performed to verify the possibility of the adaptive observer-based loosening detection.

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[in Japanese]

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In this paper, we present a multi-agent simulation model based on innovation theory and diffusion modeling that is intended for modeling a biomass utilization system. Particularly, the model has been evaluated for the collection, conversion, and subsequent distribution of fuel oil obtained from waste oil.

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[in Japanese]

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