Al₂O₃ - doped ZnO (AZO) thin films have been deposited onto glass substrates using the split target consisting of AZO (1 wt%) and AZO (2 wt%) by pulsed laser deposition method with an ArF excimer laser (λ=193 nm, 15 mJ, 10 Hz, 0.75 J/cm²). By applying magnetic field perpendicular to the plume, the lowest resistivity of 8.54×10^-5 Ω·cm and an average transmittance more than 91 % over visible range were obtained at a target to substrate distance of 25 mm for approximately 279 nm-thick-AZO film (1.8 wt%) grown at a substrate temperature of 230°C in vacuum. From the cross-sectional TEM observation and the XRD spectrum, a reason why low resistivity of the level of 10^-5 Ω·cm was reproducibly obtained was considered to be due to the fact that a disorder of crystal growth originated in the vicinity of the interface between the substrate and the film was suppressed in the application of magnetic field and the c-axis-orientation became of preference, which in turn, giving rise to the increase of mobility.

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Microfluidic systems will be widely used in the future μ-TAS and DNA analyses. Due to the small Reynolds number in a microchannel, mixing is performed by increasing the contact area between two liquid. Here, we propose an active method to stir a liquid using an optically-driven micro-rotator. In this report, we have analyzed the micro-liquid velocity vectors around the rotators at different depths for both horizontal and vertical rotations.

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We fabricated optical recording films with a laminated structure composed of ZnO and In₂O₃, prepared on glass substrates by a pulsed laser deposition method using the split target. The film compositions were varied by changing the ratio (trace ratio) of the time required to irradiate each half section (ZnO or In₂O₃) of the target by an ArF excimer laser. There were large transmittance changes ΔT in the wavelength range of 350 ∼ 3000 nm, between the state immediately after deposited at room temperature and the state annealed at 400°C for the films fabricated with various trace ratio. It was found by TEM observation and XPS measurement that a mechanism which enabled to optically record for the films with a laminated structure was ascribed to the effect changing over from the oxygen-deficient state immediately after deposited to the thermal oxidized state by annealing. The maximal value of CNR = 67 dB was obtained at a peak power of 3 mW for the sample without a protection layer fabricated at the trace ratio of ZnO : In₂O₃ = 1 : 1. When the protection layers of ZnS: SiO₂ became 30 nm, the value of CNR more than 45 dB were stably obtained in the peak power 4 ∼ 6 mW.

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It is well known that dielectric gratings with very small period can be analyzed by approximation of equivalent uniform permittivity. Metallic gratings with small period must be approximated by an equivalent sheet of surface impedance. In this paper, uniform approximation of equivalent impedance is described for electromagnetic scattering problem by two parallel metallic gratings. The scattering properties are calculated by using the uniform approximate method and by using spectral Galerkin procedure. From the comparison of the numerical results, the applicable condition of the uniform approximation is discussed against wave-length normalized period.

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We propose a modeling and rendering technique of human skin, which can provide realistic color, gloss and translucency for various applications in computer graphics.
Our method is based on volumetric representation of the structure inside of the skin. Our model consists of the stratum corneum and three layers of pigments. The stratum corneum has also layered structure in which the incident light is reflected, refracted and diffused. Each layer of pigment has carotene, melanin or hemoglobin. The density distributions of pigments which define the color of each layer can be supplied as one of the voxel values. Surface normals of upper-side voxels are fluctuated to produce bumps and lines on the skin.
We apply ray tracing approach to this model to obtain the rendered image. Multiple scattering in the stratum corneum, reflective and absorptive spectrum of pigments are considered. We also consider Fresnel term to calculate the specular component for glossy surface of skin. Some examples of rendered images are shown, which can successfully visualize a human skin.

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In recent years, MRI (Magnetic Resonance Imaging) systems have been actually requested to diagnose the moving parts of a human body such as the heart or the blood in angiography, where images should be taken in milliseconds instead of minutes. The gradient power supplies which are small but vital components for advanced MRI require higher output power capability as well as faster rise/fall dynamic response characteristics under a variety of specified current reference signals.
This paper presents a novel switch-mode gradient power amplifier using IGBTs which is connected in parallel with the conventional 4-switch full-bridge power conversion circuits at their inputs/outputs in order to realize further high-power density. To satisfy the design specifications which require minimized the ripple and improved the rise/fall dynamic response characteristics of the current in the gradient coil, a unique digital control scheme on the basis of optimal preview type-1 servo system is proposed and described in detail. The above effectiveness is discussed and evaluated through the computer-aided analysis. It is expected that the proposed techniques will highly enlarge the diagnostic target and improve the image quality of ultrahigh-speed scanning MRI.

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In cellular mobile communication systems, a channel assignment problem has been extensively studied. In order to avoid exhaustive search, the number of reallocatable channel is limited only one in TPB method which is one of dynamic channel assignment proposed by Chang. In this paper, a dynamic channel assignment by using the maximum neural network with reinforced self-feedback (MNN-RS) is proposed. From numerical experiments, it is confirmed that the proposal improves blocking probability and reduces the probability that blocking probability exceeds arrowable rate. Lastly the proposed model is implemented on Xilinx FPGA XCV300E and scalability is discussed.

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The least-square method is applied to the identification of the stop model in order to improve its hysteretic representation. It is shown that the height difference of stop hysterons should not be smaller than the amplitude difference of the hysteretic loops used for the identification. The effective magnetic field is used for the play model. It successfully improves the hysteretic representation by the play model. The comparison of both models shows that the play model using the effective magnetic field represents the hysteretic characteristics more precisely than the stop model.

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In this paper, a random-switching controller using chaos generators is employed in a DC-DC converter. By fluctuating the timing of the clock pulse for the converter, the controller can reduce the peaks of the power-spectrum of the output voltage. Different from the conventional controllers, the proposed controller exploits random noise generated by chaos generators. Therefore, the proposed controller can achieve effective reduction of the noise spectrum peak with small size of circuit. Concerning the controller designed by a 1.2 μm CMOS technology, SPICE simulations are performed to investigate the characteristics of the circuit. The SPICE simulations show that 1. the noise spectrum peak of the output voltage of the power converter is reduced more than 10 dB by employing the controller and 2. the circuit size for the proposed controller is smaller than that for the conventional controller. Furthermore, the validity of the circuit design is confirmed by experiments. The proposed controller will be applicable for most of switching power converters without design modification for the other parts.

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A low power analog matched filter circuit with smart sliding correlation is proposed for direct sequence code division multiple access (DS-CDMA) despreading process. The influence of level shifter mismatch on the trade-off between speed, power and resolution of the analog correlator circuit is investigated with respect to technology scaling. The optimization in power, acquisition time and areal efficiency is considered. Simulation with code length of 127 reveals that the analog matched filter circuit provides good linearity, and dissipates only 22 mW at a voltage supply of 3.3 V and an operational clock frequency of 128 MHz, using 0.35 μm CMOS technology.

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Recently, the semiconductor substrates for integrated circuits (ICs) have been required to become as thin as 50 mm, because the many electronic devices are strongly demanded to be miniaturized and light-weighted. Machining of such thin substrates with conventional dicing techniques is very difficult. Therefore, we have proposed to process them using femtosecond laser ablation. In this work, we have investigated the influence of conditions of doubled pulse laser such as delay time and fluence on the depth and diameter in order to develop a new dicing technique for very thin ICs. Double pulse laser ( λ = 780 nm, τ = 150 fs, ƒ = 10 Hz, Δt = 0 ∼ 100 ps, E1+E2 = 100 μJ ) was focused on the Si substrate with a plano-convex lens with a nominal focal length of 100 mm. In the case of the delay time of 10 ps, the singularly shallow and flat-bottomed holes was obtained. When the substrates have been diced on this condition, the bottom of the processing groove was flat and very smooth, whereas many microcracks started from the bottom of the groove formed by conventional method have been observed. From these results, we were able to find out the some processing conditions using femtosecond laser applicable dicing of thin Si substrate.

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Since modeling based on physical analysis of an ultra-sonic motor(USM) is difficult, conventional PID or IMC-PID control often has been used. However, it is difficult to accomplish satisfactory control performance using a conventional PID or IMC-PID control because an USM contains dynamic variations and non-linear elements.
In this paper, we propose IMC-PID control using neural networks(NN) for an USM. In the proposed method, one parameter of IMC-PID control is adjusted using NN at each sampling-time. Introduction of NN makes it possible to compensate dynamic variations and non-linearity of an USM. The effectiveness of the proposed method is confirmed by experiment using existent USM.

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Abstract the present paper investigates attachable robust compensators design for polytopic linear parameter varying (LPV) plants using prior or real-time knowledge of the parameter. Based on each knowledge, this paper explores both robust LPV system and robust gain scheduled system design method. Quadratic L₂ gain performance framework and robust model matching (RMM) strategy are combined to develop compensators. Namely, a RMM design method, that is, a practical approach to the design of attachable robust compensators for the linear time invariant (LTI) plant, is extended for application to the LPV plant. A design example and simulation results are presented in order to demonstrate the proposed method.

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This paper described a compensation method for actuator dead-zone in mechatoronic servo systems. The proposed compensation method used a concept of the nonlinear separation control, and diminished dead-zone defect by taking an inversion of the dead-zone characteristics. The proposed dead-zone compensation by nonlinear separation control has been successfully applied to contour control of a pantograph type robot arm and stability control of an inverted pendulum.

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Shaft inserting is important and frequent operation for the automatic parts assembling. We have developed a shaft inserting system for the moving object using the robot with a cross PSD sensor. This PSD sensor can detect the position error and the angle of the target hole in real time. In this paper, we show the detecting characteristics of the inclined angle of the target hole for the cross PSD. Also we show the system diagram of the robot system with the cross PSD sensor. Then we propose the shaft inserting algorithm. By using this system, the robot can insert a shaft into a hole of the moving object with the clearance of 50μm at a velocity of 40mm/s in the case of setting the inclined angle within 5 degree. Our proposed sensor based system is effective for the shaft inserting into the hole of the moving object.

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This paper describes a “Ubiquitous Personalize Agent” and it’s application: “Shopping assistance service” for ubiquitous environments. Ubiquitous personalize agent is realized based on context reasoning technology. It can determine contexts of users by referring a lot of data which can be retrieved from devices in ubiquitous environments. We also have had an experimental trial of this service. In this paper, we state the technology, service, and evaluation on the experimental trial.

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We propose a parallel genetic algorithm with sexual selection. In genetic algorithms with sexual selection with one population, females keep their traits around local optima by using lower mutation rate than males’ one, while males change their traits actively. When a runaway process takes place, the transitions of males’ traits are biased toward a certain direction which is decided by the bias of females’ preferences. If the population size is large, the search converges quickly. The large population size, however, causes the decrease of the search performance. In the proposed method with parallelization, the population size of each sub-population is kept adequately, and each sub-population searches its own direction of evolution independently. As a result, the proposed method makes a search converge quickly because the runaway process which leads to the intermittent evolution tends to take place more quickly than one population model. We applied the proposed method to some test problems. In these problems, while the performance of conventional genetic algorithms decreased by parallelization, the proposed method revealed better performance by parallelization. Moreover, the performance of the proposed method was better than the ones of conventional methods. This availability of parallelization is characteristic of the sexual selection.

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In this paper, we describe a new crowd flow simulation method which combines the multi-agent (MA) with the cellular automata (CA). The features of our simulation method are that the behavior of a crowd is formed by autonomous action of heterogeneous agents, and that the action is interrupted by asynchronous intervention from environment. In this method, each agent is located on a continuous plane, and its position is represented by coordinate of real number. Based on agent attribute parameters, which are different in every agent, and mutual position relations with other agents at that moment, an agent begins to move on the continuous plane. We develop the simulator based on these techniques, and analyze crowd behaviors, in particular, collided crowds ones. By the simulation experiments, we confirmed that using the simulation system implemented by this method, the interesting behavior of the movement of the actual crowd behavior can be reproduced.

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This paper describes an artificial immune network with multi-layered B cells architecture. It is not our concern to reproduce with confidence any immune phenomenon, but to show that immune concepts can be used to develop powerful computational tools for engineering applications. As an important result of our model based on multi-layered B cells architecture, the network is capable of creating better immune response and describing pattern category for arbitrary sequences of analog (gray-scale, continuous valued) input patterns, as well as binary input patterns.

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In order to build the Web-based application as a shopping site on the Web, various ideas from the different viewpoints are required, such as enterprise modeling, workflow modeling, software development, and so on. From the above standpoint, this paper proposes an integrated environment to support the whole development process of analysis, design and implementation of business application. In order to reuse know-hows of various ideas in the business application development, we device a multi-grain-size repository, which consists of coarse-, middle-, and fine-grain-size repositories that correspond to the enterprise models, workflow models, and software models, respectively. We also provide a methodology that rebuilds heterogeneous information resources required for the business applications development into a multi-grain-size repository based on ontologies. The contents of the repositories are modeled by the is-a, has-a, and E-R relations, and described by the XML language. We have implemented Java-based prototype environment with the tools dealing with the multi-layered repository and confirmed that it supports us in various phases of business application development including business model manifestation, detailed business model definition and an implementation of business software applications.

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In order to distinguish malignant from benign skin lesions dermatologists use a microscope that shows the pigmented structure of the skin. However, it can be difficult to classify a skin lesion as benign or malignant using a dermoscopic image alone. This motivates computer analysis of dermoscopic images by digital image processing. The first step for a computer analysis is the segmentation of the image into regions of the same color, i.e. regions of the same color should be assigned the same gray level and regions of different colors should be assigned different gray levels. The number of colors is not known in advance. This paper presents a color clustering method that determines the number of colors automatically. First the RGB image is transformed into the L^∗u^∗v^∗ color space and segmented by a self-organizing map (SOM). After completion of the training a genetic algorithm groups the SOM neurons into clusters searching for a grouping that optimizes the Davies-Bouldin index. Various genetic algorithms are presented and evaluated for this purpose.

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As a handy optical space communication system which can be used for school Internet access net building.
1) The examination of the irregularity demodulation form.
2) The development of the most reliable technology which realizes long-distance communication by the high trust.
3) The development of the Point to Multi Point (P-MP) machine which it can communicate by at the same time with the several places due to the realization of the multiplex communication technology.
4) Even if a child sees directly, the research and development of the high-speed big capacity technology in the wavelength obi which harm is not in.

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