The purpose of this study is to propose an advanced phase-based optical flow method with improved tracking accuracy for motion flow. The proposed method is mainly based on adaptive bilateral filtering (ABF) and Gabor based spatial filtering. ABF aims to preserve the maximum boundary information of the original image, while the spatial filtering aims to accurately compute the local variations. Our method tracks the optical flow in three stages. Firstly, the input images are filtered by using ABF and a spatial filter to remove noises and to preserve the maximum contour information. The component velocities are then computed based on the phase gradient of each pixel. Secondly, irregular pixels are eliminated, if the phase differences are not linear over the image frames. Lastly, the entire velocity is derived by integrating the component velocities of each pixel. In order to evaluate the tracking accuracy of the proposed method, we have examined its performance for synthetic and realistic images for which the ground truth data were known. As a result, it was observed that the proposed technique offers higher accuracy than the existing optical flow methods.

High Dynamic Range (HDR) images have been widely applied in daily applications. However, HDR image is a special format, which needs to be pre-processed known as tone mapping operators for display. Since the visual quality of HDR images is very sensitive to luminance value variations, conventional watermarking methods for low dynamic range (LDR) images are not suitable and may even cause catastrophic visible distortion. Currently, few methods for HDR image watermarking are proposed. In this paper, two watermarking schemes targeting HDR images are proposed, which are based on µ-Law and bilateral filtering, respectively. Both of the subjective and objective qualities of watermarked images are greatly improved by the two methods. What's more, these proposed methods also show higher robustness against tone mapping operations.

We present the PCA self-cross bilateral filter for denoising multi-modal images. We firstly apply the principal component analysis for input multi-modal images. We next smooth the first principal component with a preliminary filter and use it as a supplementary image for cross bilateral filtering of input images. Among some preliminary filters, the undecimated wavelet transform is useful for effective denoising of various multi-modal images such as color, multi-lighting and medical images.

A communication means is presented for patients with amyotrophic lateral sclerosis in totally locked-in state who are completely unable to move any part of the body and have no usual communication means. The method utilizes changes in cerebral blood volume accompanied with changes in brain activity. When a patient is asked a question and the answer to it is 'yes', the patient makes his or her brain active. The change in blood volume at the frontal lobe is detected with near-infrared light. The instantaneous amplitude and phase of the change are calculated, and the maximum amplitude and phase change are obtained. The answer 'yes' or 'no' of the patient is detected using a discriminant analysis with these two quantities as variables. The rate of correct detection is 80% on average.

In this paper we modeled and analyzed the ridge type InGaAlAs/InP semiconductor laser with lateral current confinement structure, and optimized the design for the ridge wave guide with the current confinement. We proposed and fabricated the ridge type InGaAlAs/InP laser with a cost effective selective undercut etching method and demonstrated the improvement of the ridge laser performance. This paper provides a solution to solve the cost/yield issue for conventional BH (buried hetero-structure) type laser and performance issue for conventional ridge type laser.

The role of electric field in metal-induced lateral crystallization (MILC) of amorphous Si (a-Si) under limited Ni-supply condition has been investigated. The nominal lateral-growth rate was increased from 3.6 µm/h (no-electric field) to 23 µm/h at the positive electrode side and reduced to 2.8 µm/h at the negative electrode side in presence of the electric field of 20 V/cm. However, spontaneously nucleated needle-like Si crystals were observed in the enhanced positive electrode side, which have been found to be independent of the MILC. Further investigation under the condition where Ni in the supply region was removed on the way of crystallization revealed that the electric field enhanced crystallization greatly reduced. These results indicate that the electric field does not enhance the MILC growth but enhances the diffusion of Ni in a-Si which takes place prior to the MILC growth.

In this report, we propose a tracking algorithm of speaker direction using microphones located at vertices of an equilateral triangle. The method realizes tracking by minimizing a performance index that consists of the cross spectra at three different microphone pairs in the triangular array. We adopt the steepest descent method to minimize it, and for guaranteeing global convergence to the correct direction with high accuracy, we alter the performance index during the adaptation depending on the convergence state. Through some computer simulation and experiments in a real acoustic environment, we show the effectiveness of the proposed method.

This paper proposes an independent control for parallel-connected multiple uninterruptible power supply (UPS) systems based upon a very simple control scheme. Here, the amplitude and phase angle of the output voltage are the controllable variables. With the only measurement of the output current, the active and reactive components are calculated to define the control variables. The entire system including the equations for the circuit, control and voltage limiters is well represented by a small-signal model, in which the computation of its eigenvalues constitutes the stability proof of the system. The root locus diagram gives an overall panorama of the system performance as a function of a certain gain and it aims to aid the further understanding and the design of the control. The experimental verification is carried out using a mere proportional-integral control scheme, which is a special case of the general control equation used in the theoretical analysis. For some situations, experiments show a flow of lateral current between UPS's, which causes an unbalanced current distribution. By increasing the proportional gain of the control equation for the output voltage amplitude, the lateral current can be substantially suppressed with a consequent improvement of the load sharing. Experimental results under various conditions show excellent results in terms of synchronization, load sharing and stability for three distinct output rating UPS's connected in parallel.

This paper presents ACIS, an Autonomous Community Information System. ACIS is a proposition made to meet the rapidly changing users' requirements and cope with the extreme dynamism in current information services. ACIS is a decentralized bilateral-hierarchy architecture formed by a community of individual end-users (community members) having the same interests and demands at specified time and location. It allows those members to mutually cooperate and share information without loading up any single node excessively. In this paper, autonomous decentralized community construction and communication technologies are proposed to assure a productive cooperation, a flexible and timely communication among large number of community members. The main ideas behind the proposed communication technology are: content-code communication (service-based) for flexibility and multilateral benefits communication for timely and productive cooperation among members. All members communicate productively for the satisfaction of all the community members. The scalability of the system's response time regardless of the number of the community members has been shown by simulation. Thus, the autonomous decentralized community communication technology reveals interesting results when the total number of members in the community increases dramatically.

Autonomous Decentralized Community Information System (ADCS) is a proposition made to meet the rapidly changing users' requirements and cope with the extreme dynamism in current information services. ADCS is a decentralized architecture that forms a community of individual end-users (community members) having the same interests and demands in specified time and location. It allows those members to mutually cooperate and share information without loading up any single node excessively. In this paper, an autonomous decentralized community communication technology is proposed to assure a productive cooperation, a flexible and timely communication among the community members. The main ideas behind this communication technology are: content-code communication (service-based) for flexibility and multilateral communication for timely and productive cooperation among members. All members communicate productively for the satisfaction of all the community members. The scalability of the system's response time regardless of the number of the community members is shown through simulation. Thus, the autonomous decentralized community communication technology reveals significant results when the total number of members in the community increases sharply.

A two-dimensional laser beam profiler has been developed that can measure the intensity distribution on a sample surface of a single-shot of an excimer-laser light beam from not only the macroscopic viewpoint, but also the microscopic viewpoint, which is important to excimer-laser triggered lateral large-grain growth of Si. A resolution as fine as 0.4 µm was obtained with a field of view of as large as 30 µm 30 µm. The effects of homogenizers, phase-shifters, and their combination on beam profiles were quantitatively investigated by using this apparatus. The relationship between the microscopic beam profile and the surface morphology of laterally grown grains was also examined.

Small-size MOSFETs are becoming core devices in RF applications because of improved high frequency characteristics. For reliable design of RF integrated circuits operating at the GHz range, accurate modeling of small-size MOSFET characteristics is indispensable. In MOSFETs with reduced gate length (Lg), the lateral field along the MOSFET channel is becoming more pronounced, causing short-channel effects. These effects should be included in the device modeling used for circuit simulation. In this work, we investigated the effects of the field gradient in the gate-drain capacitance (Cgd). 2-Dimensional (2D) simulations done with MEDICI show that the field gradient, as it influences the channel condition, induces a capacitance which is visible in the MOSFET saturation operation. Changes in Cgd is incorporated in the modeling by an induced capacitance approach. The new approach has been successfully implemented in the surface-potential based model HiSIM (Hiroshima-university STARC IGFET Model) and is capable of reproducing accurately the measured Cgd-Lg characteristics, which are particularly significant for pocket-implant technology. Results show that pocket-implantation introduces a steep potential increase near the drain region, which results to a shift of the Cgd transition region (from linear to saturation) to lower bias voltages. Cgd at saturation decreases with Lg due to steeper surface potential and increased impurity concentration effects at reduced Lg.

We have successfully produced laterally-grown grains on large (300 350 mm) glass substrates by means of a newly developed excimer laser crystallization system that features a high-precision mask stage and an auto-focusing system. The original grains were produced with a steep beam edge and their lateral growth was extended by repeated irradiation and translation. TFTs fabricated with these extended grains were found to have mobilities that remained almost constant at 270 cm2/Vs (n-ch. TFTs) and 230 cm2/Vs (p-ch. TFTs) over a wide range of laser fluence (400-600 mJ/cm2).

A great deal of effort has been concentrated on the longitudinal control for the collision avoidance of moving vehicles. In an emergency as well as in a normal situation, however, the steering control can be a very effective alternative as observed in the practice of manual evasive driving. In the reported methods of steering control, it is found that the dynamic motions of the neighboring vehicles are often ignored, which may result in some danger of 2nd collision. Therefore, it is necessary to assess the surrounding traffic situation to prevent 2nd collision that can occur just after escaping from the 1st collision situation. In this paper, we tackle the collision avoidance problem when steering actuation control is allowed in consideration of the dynamic motion of the neighboring vehicles. Specifically, a hierarchical control scheme is suggested as a feasible solution, and the proposed system is verified via simulation using a software simulator called DevACAS (DEVeolper of Active Collision Avoidance System), which we have developed.

The epitaxial lateral overgrowth (ELO) of GaN with a stripe tungsten (W) mask pattern is performed by hydride vapor phase epitaxy (HVPE) and the crystalline and optical properties are investigated compared with ELO GaN using SiO2 mask by characterizations of X-ray rocking curve (XRC), transmission electron microscopy (TEM) and low temperature cathodoluminescence (CL). A buried ELO structure of the W mask with a smooth surface is successfully obtained. The tilt of c-axis on the W mask in the ELO GaN is not observed, but in the case of the SiO2 mask, c-axis tilts on the mask region at 1 to 10 together with small angle grain boundaries. Half the way from the ELO interface to the surface, the luminescence becomes excitonic over the whole lateral extension region, which indicates the optically high crystalline quality of the material. On the other hand, different kinds of luminescence are observed depending on the position. The difference of these luminescence is caused by the defects and/or impurity incorporation on the mask region due to the tilting of c-axis.

In coupled oscillator arrays, it is possible to control the inter-element phase shift up to 180 by free-running frequency distribution based on injection-locking phenomenon. In this paper, a new technique to control the inter-element phase shift electronically up to the maximum extent of 360 is reported. Oscillators are unilaterally coupled to the preceding oscillator through one of the two paths, which differ from each other 180 in electrical length and each includes an amplifier. Turning on the desired amplifier one can control the phase shift either -180 to 0 or 0 to 180. The technique was applied in a three-element oscillator array each coupled to a patch antenna via a round aperture. The radiation beam of the array could be scanned 47 in total.

We fabricated a new lateral Power MOS FET with an SOI structure formed by a solid phase epitaxy method which has a buried gate under the channel layer and a trench gate/drain. We studied the temperature dependence of the Vg-Id characteristic and Vd-Id characteristic in the temperature range of from 27 to 150. In the Vd-Id characteristic, the drain current decreases as the temperature increases in the saturation region, but the drain current increases as the temperature increases in the linear region. Zero-temperature-coefficient bias point of Vg-Id characteristic was 0. 3 V. And, the threshold voltage variation was -2. 8 mV/. In the Vd-Id characteristic, the drain current decreases as the temperature increases. The specific on-resistance was obtained in the linear region of the Vd-Id characteristic. The specific on-resistance variation was 0. 3 mWmm2/. The temperature characteristics of this device are as good as those of the conventional MOS FET.

An individual identification system is developed. In this system, we unify profile curve identification and full face image identification to obtain more successful recognition rate. In profile cruve identification process, the P-type Fourier descriptor is made use of. In full face image identification process, mosaic density values are made use of. A combination of the two processes shows higher recognition rates than those obtained by each single process.

Using fundamental device and circuits, we have realized three functions required for synaptic connections in self-organizing neural networks: long term memory of synaptic weights, fixed total amount of synaptic weights in a neuron, and lateral inhibition. The first two functions have been condensed into an optical adaptive device and circuits with floating gates. Lateral inhibition has been realized by a winner-take-all circuit and a following lateral excitatory connection circuit. We have fabricated these devices and circuits using CMOS technology and confirmed the three functions. In addition, topological mapping, which is essential for feature extraction, has been formed in a primitive network constructed with the fundamental device and circuits.

This paper discusses crystal-growth and device-design issues associated with the development of high-performance InP/InGaAs heretostructure bipolar transistors (HBTs). It is shown that a highly Si-doped n+-subcollector in the HBT structure causes anomalous Zn redistribution during metalorganic vapor phase epitaxial (MOVPE) growth. A thermodynamical model of and a useful solution to this big problem are presented. A novel hybrid structure consisting of an abrupt emitter-base heterojunction and a compositionally-graded base is shown to enhance nonequilibrium base transport and thereby increase current gain and cutoff frequency fT. A double-heterostructure bipolar transistor (DHBT) with a step-graded InGaAsP collector can improve collector breakdown behavior without any speed penalty. We also elucidate the effect of emitter size shrinkage on high-frequency performance. Maximum oscillation frequency fmax in excess of 250 GHz is reported.