Nowadays agile market is in common, and the fundamental technology supporting next-generation production system requires further development of machine and information technologies to establish “human technology” and a bridging of these technologies together. IMS-HUTOP project proposes a new product life cycle that respects the human nature of individuals, and establishes the elemental technologies necessary for acquiring, modelling and evaluating various human factors in an effort to achieve the HUTOP cycle. In this paper we propose a human centred KANSEI manufacturing system, which has been proposed in the IMS-HUTOP project with 5 work packages.

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B to B commerce is an important research issue for increasing profitability in global market. A sophisticated B to B commerce requires optimality in resource allocation with human behaviour dynamism. A market-oriented programming calculates a Pareto-optimal resource allocation in the market by computing competitive equilibrium of an artificial economy. In this paper we newly propose a resource allocation algorithm based on market-oriented programming with consumers buying behaviour for B to B commerce. Supply agents in the computational market decide their supply plan by estimating the demand agents’ behaviour in this method. Careful constructions of the agents according to the buying behaviour can lead to efficient distributed resource allocation, and the behaviour of the agents can be analysed in economic terms.

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The influence of strict defect control is both the enhancement of manufacturing yield and the delivery delay due to the drop of the machine operation rate. Therefore defect inspection method must be optimized especially for ASIC manufacturing. In the second report, we formularized the inspection parameter dependence on manufacturing yield and machine cleaning cycle that may affect delivery time. In this report, we propose new cost model which can take account of manufacturing yield drop, delivery delay cost etc. The delivery delay cost is based on queuing theory. In the last section of this report, we propose inspection parameter setting methodology to minimize chip cost.

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This paper presents a 3D catalog system that uses Augmented Reality technology. The use of Web-based catalog systems that present products in 3D form is increasing in various fields, along with the rapid and widespread adoption of Electronic Commerce. However, 3D shapes could previously only be seen in a virtual space, and it was difficult to understand how the products would actually look in the real world. To solve this, we propose a method that combines the virtual and real worlds simply and intuitively. The method applies Augmented Reality technology, and the system developed based on the method enables users to evaluate 3D virtual products in a real environment.

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A decision model stemmed from Bayesian theorem is proposed to describe the process of decision making for job sequence in manufacturing system. The construction of feature vector is firstly discussed with respect to the manufacturing system’s characteristic. Then a non-parametric model is employed to deal with general distribution for decision acquisition, where a binary division methodology is developed to limit the size of non-parametric model, including elimination of irrelevant features. At last, a PCB manufacturing system is given to demonstrate the efficiency of the model.

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In recent years, advances in computer and communication technology and the associated rapid increase in the number of Internet users are encouraging advances in Electronic Commerce (EC). Business models of EC are being actively developed by many different enterprises and engineers, and implemented in many kinds of fields. Meanwhile Web services that reuse remote components over the Internet are drawing attention. Web services are based on SOAP/WSDL/UDDI and are given an important position as the infrastructure of the EC systems. The article analyzes the functions and structures of various business models, establishing the patterns of their distinctive and common features, and proposes a method of determining the implementation specifications of business models utilizing these patterns and Web service functions. This method has been applied to a parts purchasing system, which is a typical pattern of the B to B (Business to Business) EC applications. The article also discusses the results of evaluating this prototype system.

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In order to realize “the product life cycle with respect for human nature". we ought to make work design so that work environment should be configured to be sound in mind and body, with due consideration of not only physical but also mental factors from the viewpoint of workers. The former includes too heavy work, unreasonable working posture, local fatigue of the body, the safety, and working comfort, and the latter includes work motivation, work worthiness, stress, etc.
For the purpose of evaluating the degree of working comfort and safety at human-oriented production lines, we acknowledged, for the work design, the effectiveness of the work designing technique with working time variation duly considered. And, we formulated a model for a mental factor experienced by workers from the degree of working delays. This study covers a work design technique we developed with the effect of the factor as the value of evaluation.

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This paper presents a novel system prototype of auxiliary resonant DC link (ARDCL) assisted three phase double converter using IGBT power modules. In the ARDCL-based double converter, large current flows through the ARDCL circuit when the ARDCL circuit operates under heavier load current ranges. In addition to this, the gate pulse control timing sequences for switching power semiconductor devices used in the ARDCL circuit become more complicate actually.
The active auxiliary resonant DC link snubber circuit has advantage point of small load currents which flow through the ARDCL circuit and does not actually require the complicated timing pulse control implementation for switching power semiconductor devices. In this paper, the system configuration double converter circuit and its operation principle are described for three phase voltage source type double soft-switching converter with a single ARDCL snubber. For a 10kVA prototype double converter system, conversion efficiency can be improved in addition to noise terminal voltage is reduced up to 20dBuV in maximum in the switching frequency range of 500kHz or more in comparison with the conventional three phase hard switching double converter system.

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The research group in Musashi Institute of Technology is currently concentrating on the increase of the total efficiency for driving rope-less elevator using Linear Synchronous Motor (LSM). Since it is rope-less, counter weight cannot be installed in the system. Thus, the linear motor should output higher thrust force. The increase of the efficiency of LSM itself is one of the concerns, and the other is the high-efficiency drive control method. The former is considered in our laboratory. Therefore, We think that it is necessary for the design of efficient control system to grasp the change of the efficiency depending on the driving condition, such as load mass, velocity and required thrust force. The dynamic control method changing the operating point to pursue the maximum power is known as the Maximum Power Point Tracking (MPPT). This approach is useful and can be applied to the control of LSM for rope-less elevator. The cage of rope-less elevator repeats acceleration and deceleration periodically, in ascent and descent. The optimum-minimum-energy consumption is obtained if the system is always operated at the maximum efficiency, even if the drive condition changes. The basic characteristics of LSM for rope-less elevator are discussed first in this paper. The efficiency characteristics of the LSM are shown and the maximum efficiency loci are derived next as the only pair of a current and a power angle for one condition. Moreover, the MPPT controller of LSM is fully designed, and the results of simulation in driving the LSM using MPPT are shown.

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This paper presents a novel Genetic Algorithm (GA) based autonomous compensator design for the fast-response and high-precision positioning of mechatronic systems. The positioning system is mainly composed of a robust 2-degrees-of-freedom (2DOF) controller based on the coprime factorization description. The feedback (FB) compensator in the 2DOF controller ensures the robust nature against the variations of load mechanical parameters. The feedforward (FF) compensator, on the other hand, allows the positioning to be fast and precise. In the controller design framework, the FB/FF compensators can be autonomously designed by GA, where both the structure and parameters of the compensators are optimized to achieve the desired robust positioning performance using μ-Analysis. The effectiveness of the proposed optimal design has been verified by experiments using a prototype of 2-mass resonant system.

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In this paper we calculated magnetic flux density and eddy current distributions of a 71MVA turbine generator stator core-end using three-dimensional numerical magnetic field analysis. Subsequently, the magnetic flux densities and eddy current densities in the stator core-end region on the no-load and three-phase short circuit conditions obtained by the analysis have good agreements with the measurements. Furthermore, the differences of eddy current and eddy current loss in the stator core-end region for various load conditions are shown numerically. As a result, the facing had an effect that decrease the eddy current loss of the end plate about 84%.

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The segment core method is a popular method employed in motor core manufacturing; however, this method does not allow the stator core precision to be enhanced because the stator is assembled from many cores. The axial eccentricity of rotor and stator and the internal roundness of the stator core are regarded as the main factors which affect cogging torque. In the present study, the way in which a motor with a split-type stator generates a cogging torque is investigated to determine whether high- precision assembly of stator cores can reduce cogging torque. Here, DC brushless motors were used to verify the influence of stator-rotor eccentricity and roundness of the stator bore on cogging torque. The evaluation results prove the feasibility of reducing cogging torque by improving the stator core precision. Therefore, improving the eccentricity and roundness will enable stable production of well controlled motors with few torque ripples.

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DC-DC quasi-resonant converters (QRCs) have a highly nonlinear and time-varying behavior as well as other types of DC-DC resonant converters such as conventional and multi-resonant converters. Changing in operating conditions, mainly due to variation in load and line disturbance, leads to significant changes on system dynamics so that desired performance and even stability are lost. Taking into consideration the uprising need for high-quality resonant power converters has opened a new research window on the control of these systems using modern and systematic approaches.
In this paper in order to achieve both stability and desired performance, such as reduced sensitivity to load variations, desired disturbance rejection, reduced output impedance and attenuated transfer from input to output, we have proposed a methodology based on μ-synthesis technique for DC-DC QRCs controller design. The μ-analysis is used to verify the robustness of the designed controller. The proposed control strategy is applied to a typical zero-current switching QRC and nonlinear simulation is performed using nonlinear model of converter circuit. The simulation results demonstrate the good reference voltage tracking, line disturbance rejection and show that the designed procedure guarantees the robust stability and robust performance for a wide range of load variation.

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The initial rotor position estimation is one of some serious problems about sensorless drives of permanent magnet synchronous motor. This paper presents an estimation method of initial rotor position for interior permanent magnet synchronous motor. The principle of the estimation is based on the nonlinear magnetization characteristics of the stator core caused by the magnet of the rotor. The estimation is performed using the variation of the current response caused by the magnetic saturation when the voltage vector is applied to the motor. This method can be performed without motor parameters and any additional hardware. Decision method of the optimal voltage vector applied to the motor is also proposed to accurately implement the estimation. Experimental results show that the initial rotor position can be estimated without rotating the rotor by using the optimal voltage vector. As a result, the average of the estimation error is ±1.34 electrical degrees, and the estimation is completed within 15.2ms in the test motor.

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In power semiconductor devices, control of the temperature distribution of a silicon chip is very important. Temperature cycle of the chip surface causes the lift-off of the bonded wire by heat stress, which limits the lifetime of power modules. Optimized arrangement of the bonded position on the chip gives a possibility to reduce the temperature swing for a given power dissipation. In this paper, we try to apply electrothermal circuit simulation as a method of evaluating the temperature distribution on a chip and show that it can provide a method to optimize the layout of W/B point for reducing temperature gradient on a chip.

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A design method for reducing residual vibration and seeking noise in the short-span seeking control of a magnetic disk drive was developed. This method can optimize a seeking trajectory based on a shock response spectrum (SRS) analysis. Residual vibration and seeking noise were experimentally found to be significantly reduced by using the optimized seeking trajectory.

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The permanent magnet synchronous motor (PMSM) is an efficient machine, which has found application over wide power and speed ranges. This paper presents the optimal rotor design of a PMSM for use on a railway vehicle. This design utilizes reluctance torque in order to develop higher torque at starting with low open circuit voltage at high speed.

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Three phase voltage-source PWM converters are used as a utility interface. In such a case, the converter line currents are required to track sinusoidal references synchronized with the utility grid without a steady-state error. In this paper a current control method based on a sinusoidal internal model is employed. The method uses a sine transfer function with a specified resonant frequency, which is called an S-compensator. The combination of a PI compensator and an S-compensator is called a PIS compensator. The PIS compensator ensures that the steady-state error in response to any step changes in a reference signal at the resonant frequency and zero hertz reduces to zero. Experiment was carried out using a 1kVA prototype to verify the usefulness of the PIS compensator. Three utility-interface-converters, a voltage source PWM rectifier, an active filter, and STATCOM, were examined. Almost perfect current tracking performance without a steady-state error was observed.

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In continuous casting process, MHD calculation is utilized to make clear and design the process. Previous MHD calculation takes no account of time-varying electromagnetic force which is enough smaller than mass inertia, because previous purpose is estimation of time average major flow in interior of mold. However, to improve surface quality of slab more, the dynamic behavior of free surface where the solidification begins must be made clear in detail. In this paper, we evaluated influence that time-varying electromagnetic force exerts on the flow in MHD calculation. As the result, the flow of free surface is disordered intensely by the taking into account of time-varying electromagnetic force. Therefore, time-varying electromagnetic force must be used, to make clear the dynamic behavior of free surface. However, previous MHD calculation with small computation cost suits to evaluate major flow in interior of mold, because it is same approximately in both methods.

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This paper describes the torque characteristics of surface-mounted-PM motor with concentrated stator winding. The torque is analyzed in detail by 2D FEM, and the proposed segmented PM motor is very useful to reduce the cogging torque. The simulation results by FEM are presented together with the considerably reduced rotor iron structure.

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This paper proposes a novel method of detecting the active and reactive currents in single-phase circuits using the correlation and cross-correlation coefficients in the time domain. The active current is detected using the correlation coefficient between the source voltage waveform and load current waveform, and the reactive current is detected using the cross-correlation coefficient. The basic principle of the proposed detection method is discussed in detail, and then confirmed by digital computer simulation. Digital computer simulation results demonstrate that the proposed method can detect the active-reactive current in single-phase circuits in the time domain.

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