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In this study, we report the growth of semipolar InN films on r-plane (10-12) substrates by radio-frequency plasma-assisted molecular beam epitaxy (RF-MBE). Semipolar InN films were successfully obtained by controlling the substrate nitridation temperature between 400°C and 600°C. We characterized the epitaxial relationship between r-plane sapphire and the obtained semipolar films using X-ray diffraction (XRD). It is found that c-axis of semipolar InN was declined by 21°from the direction perpendicular to r-plane sapphire surface along a-axis of InN.

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By irradiating ArF excimer laser (λ=193 nm) with energies density 0.8 ∼ 1.4 J/cm² on the targets of ITO and AZO (Al-doped zinc oxide) by turns, the laminated transparent conducting films composed of ITO (50 nm)/AZO (250 nm) with a total films thickness of 300 nm were fabricated at substrate temperature of 220°C. At laser energy density of 1.2 J/cm², a sheet resistance of 6.12 Ω/_??_ was obtained under conditions of oxygen pressure of 0.5 Pa for ITO. In addition, electrical characteristics of the laminated transparent conducting composed of ITO/AZO was equal to or more than that of ITO (300 nm). As a result, about 80 percent consumption of ITO was reduced at its maximum. After having examined environmental load, the sheet resistance of the laminated ITO/AZO transparent conductive oxide films did not change and therefore, the durability to the environmental conditions was maintained.

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The Al-doped ZnO (AZO) films and ZnO buffer layer were deposited on cyclo-olefin polymer (COP) substrates by pulsed laser deposition (PLD) method using ArF excimer laser (λ = 193 nm) with an energy densities of 1.0 ∼ 2.5 J/cm². Film structure was composed of a 150 nm-thick AZO film, a 100 nm-thick ZnO buffer layer, and a 188 μm-thick COP substrate. As a result, in the range of 1.0 ∼ 2.5 J/cm², Hall mobility and carrier concentration were found to decrease linerly. Therefore, the lowest resistivity of 2.77×10^-4 Ω-cm was obtained at laser energy density of 1.0 J/cm². By the results of FE-SEM photograph and AFM image of a AZO / ZnO / COP structure deposited at a laser energy density of 1.0 J/cm², it was found that smooth-surface-films with average roughness of 4.26 nm and AZO / ZnO films of good quality without cracked or flaked conditions were obtained. This will enables us to realize low-cost, lightweight, and flexible devices.

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This recerch aimed at the high output of FL by the multiplexing of the plural laser output. Plural Er-FLM that doesn't choose an oscillation wavelength automatically optimize of AWG coupler transparent wavelength by incorporate an AWG coupler in a resonator. It is multiplexed plural Er-FLM by one single mode fiber. When I use this method, it is multiplexed plural Er-FLM by one single mode fiber and developed FL of the high output and the brightness.
As a result, oscillation wavelength of Er-FLM automatically optimize of AWG coupler transparent wavelength in the 1540.2nm to 1562.6nm every about 3.2nm. Output power that multiplexed eight set Er-FLM is 81.3mW. This is 8 times of the single Er-FLM output (10mW). Consequently, scaling law of the FL output multiplexed a wavelength for the number of the input ports was passed.

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Wide band spectra were observed from Bi doped silica fiber. The FWHMs of spectra were 322 nm and 155 nm for 804 nm and 977 nm excitation, respectively. These wide band characteristics of this infrared light source will improve the axial resolution of the optical coherence tomography (OCT) technology. The estimated resolutions are 2.0 μm and 3.4 μm for spectra from 804 nm and 977 nm excitation, respectively. Bi doped silica fiber is a promising material for infrared broad band light source, such as OCT.

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We analyze the optical properties of a one-dimensional photonic crystal containing a twisted nematic liquid crystal (NLC) defect layer. For randomly polarized light incidence, two photonic defect modes were found to appear in the photonic band gap of the one-dimensional photonic crystal, and were associated either with the molecular long axis experiencing the averaged extraordinary refractive index or the molecular short axis experiencing the averaged ordinary refractive index, of the defect NLC layer. Numerical analyses also revealed that the transmitted light at the defect mode is linearly-polarized light at an angle which is determined both from the twist angle of the twisted NLC and the resulting optical rotatory power. When the thickness of the defect layer is sufficiently thin, optical rotation can be ignored and the output polarization angle is at half the twist angle for the long axis mode and at 90 degrees to that for the short axis mode.

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In web service, the server is normally responsible for the connection termination. That would produce useless connections. In this paper, to improve quality of web service, we propose two methods in which a client terminates the connection, and evaluate their performance via simulation. One method is to terminate a persistent connection under HTTP/1.1 by the client. As the simulation result, we confirmed the effectiveness of this method by comparing with the existing one. The other method is that, by using a TCP reset packet, a client terminates the suspended connection which is revealed when the client quits the browse. As the simulation result, we confirmed that this method reduces a connection loss probability when the listenbacklog parameter value is large.

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We developed a patterning technique for nerve cells that uses polytetrafluoroethylene (PTFE) and poly-D-lysine (PDL). The PDL layer on the PTFE substrate acted as a buffer for nerve cell adhesion, while Ar ion-irradiated areas on PTFE were used for separation of nerve cells. This structure was then used as a scaffold. A matrix circuit of nerve cells with dendrites or axons was subsequently observed on the scaffold after a week of cell culture. The Ar ion-irradiated area exhibited graphite or amorphous carbon, and PDL was detached from carbon grains by mechanical stress during cell culture. A possible explanation for the adhesion between PDL and PTFE is the van der Waals force. The stress between PDL/PTFE was reduced by the flexibility of PDL gel, which prevented separation of PDL from PTFE.

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In this paper, motion control for omni-directional vehicle with ball wheels is considered. The proposed omni-directional vehicle has two ball wheels, and the actuators are arranged to X-direction and Y-direction in ball wheel. Hence, omni-directional vehicle has the ability to move in arbitrary speed and direction, and has also the ability to turn around the place. The proposed control system consists of the fixed gain feedback controllers and self tuning fuzzy controllers. To achieve improvement of responses, rules of fuzzy controller are automatically adjusted by a tuning law. To achieve improvement of mobility, the optical mouse sensor is installed on omni-directional vehicle for self-localization. The experimental results demonstrate the effectiveness of the proposed system for improvement of the movement performance of the omni-directional vehicle.

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In many engineering fields, distance to target is very important and fundamental information. Acoustical signal often plays an essential role in measurement of distance. Though there are distance measurement methods using a time delay between transmitted and reflected waves, it is difficult to measure short distance because the reflected waves are often buried in the transmitted wave for short distance. Recently, a method for measuring the short distance has been proposed using standing wave. We applied the fundamental principle of this method to the estimation of short distance using audible sound as a transmitted wave. This method enabled us to obtain range spectrum from power spectrum of composite sound, but it required Fourier Transfom twice. This paper introduces the chirp signal, which is a signal such that the frequency changes with lapse of time, as a transmitted wave, and an interference arises due to the superposition of transmitted and reflected waves. Since the period of power fluctuation for the composite sound is inversely proportional to the distance between microphone and target, we propose a new distance estimation method by using chirp signal as a transmitted wave. Finally, we also confirm the validity of the proposed method through computer simulation and by experiment in an actual sound field.

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In the Decision Support Method with AHP, there is a tendency for accuracy to fall remarkably when only qualitative criteria estimate alternatives. To solve this problem, it is necessary to define the setting method of criteria clearly. Evaluation Grid Method can construct the recognition structure, which is the element of the target causality model. Through the verification of the hypothesis, the criteria of AHP can be extracted.
This paper proposes how to model human's recognition structure with Evaluation Grid Method, and how to support the decision with AHP using the criteria which constructs the model. In practical experiments, the proposal method contributed to creation of objective criteria, and examinees were able to receive the good decision support.

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In this letter, Er-doped LiNbO₃ waveguide-typed light amplifiers made with Yb co-dope technique are investigated from the point of view of gain improvement. The Ti-diffused waveguide light amplifiers are fabricated in Er/Yb co-doped LiNbO₃ substrate, and benefits of Yb co-doping are provided by comparing with the conventional Er-single doping in gain measurement. It is also shown experimentally that the high-index clad-loaded waveguide configuration is more advantageous in the gain improvement than the conventional non-clad waveguide.

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The principles of multiple block code (MBC) that feature in filter-less clock recovery are overviewed. Jitter generations are discussed to show that reducing the total amount of delay in MBC family coding can lead to suppressing jitter generation. Jitter accumulation in the repeater chain is also discussed to show that applying very low-Q filtering can drastically reduce the accumulation of high-frequency jitter. New members of MBC family codes for clock recovery with low-Q filtering that can reduce the total amount of delay in coding by a factor of six at the most are proposed. It is confirmed in an experimental set up that pattern dependent jitter can be reduced by a factor of three. An extended version of family members that can improve coding efficiency are proposed and confirmed in an experimental set up.

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This paper addresses a state-estimation problem for nonlinear systems with non-Gaussian noise and an interval constraint on the state vector. We propose new efficient algorithms, which are based on Unscented Kalman filter(UKF) and Ensemble Kalman filter(EnKF). We use Truncated UKF in Gaussian sum filter(GSF) framework, which is named Constrained Unscented GSF. And we proposed an Efficient constrained EnKF, which does not require to solve complex optimization problem like a conventional method. The validity of the proposed methods is illustrated in numerical examples.

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Chirp Pulse Microwave Computed Tomography (CP-MCT) that was originally developed for noninvasive imaging of a human body was applied to visualize sugar distribution inside a fruit. It can visualize not only permittivity distribution itself of a fruit but also various physical- or chemical-quantities relating to the permittivity value. Almost all fruits are dielectric materials containing much water, sugar, acids and so on. But for water, the principal ingredient of a fruit is sugar. Most of the fruits contain sugar from 8% to 22% by weight at the harvest time. Therefore sugar content distribution should be measured by CP-MCT nondestructively. By using apples and Japanese pears, feasibility of sugar distribution imaging has been evaluated by comparing the gray level of CP-MCT and sugar content of the cross section. The averaged correlation coefficients of the apple and pear are 0.793 and 0.681.

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Many methods for video surveillance have been developed. Robust tracking and high-performance classification are required for secure surveillance. In this paper, we propose a new recognition system that can track moving objects such as pedestrian, and classify them using a single camera in an open space parking. The proposed system can 1)perform robust object tracking and classification over occlusion and crossing; 2)look a local region of object image; and 3)integrate all processes into time series data flow. For object tracking, we developed a new agent tracking algorithm. A number of agents are generated for each object, and independently search and move to the future position by looking a local region's feature of their objects. Then they agents get fitness values, and the object ID of its local region is updated. For object classification, we forge a strong classifier from weak classifiers using AdaBoost. In practice, we recorded some scenes in an outside parking using a video camera, and tried to track objects and classified them into “person” or “vehicle”. As a result, we achieved over 97% for tracking success rate, and over 87% for classification success rate.

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This paper describes a reliable method developed for a view-based navigation which uses approximate planes of image pixel brightness in which edge-based information has been modified with a least-square algorithm. The system developed in this work have shown not only the robustness of this method to ambient lighting conditions due to indoor illumination or daylight from windows, but also the high capability of its noise rejection for images taken in recording runs. This method has been found to be highly tolerated in larger ambient illumination change than the used conventional method where brightness-based pixel values are utilized. Based on this scheme, the experiment has been successfully made in the navigation test even if large ambient lighting condition was given to the robot by means of the change in the number of the luminescent lamps or in the night and the day.

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Deregulation has been accelerating several activities toward reengineering business processes, such as railway through service and modal shift in logistics. Making those activities successful, business entities have to regulate new business rules or know-how (we call them ‘constraints’). According to the new constraints, they need to manage business resources such as instruments, materials, workers and so on. In this paper, we propose a constraint analysis method to define constraints for task planning of the new business processes. To visualize each constraint's influence on planning, we propose a network model which represents allocation relations between tasks and resources. The network can also represent task ordering relations and resource grouping relations. The proposed method formalizes the way of defining constraints manually as repeatedly checking the network structure and finding conflicts between constraints. Being applied to crew scheduling problems shows that the method can adequately represent and define constraints of some task planning problems with the following fundamental features, (1) specifying work pattern to some resources, (2) restricting the number of resources for some works, (3) requiring multiple resources for some works, (4) prior allocation of some resources to some works and (5) considering the workload balance between resources.

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In this paper stacked NOR type MRAM with vertical spin transistor has been newly proposed. Word line scheme surrounded by vertical spin transistor enable to realize small cell size of 9F² and fast random access time competitive to DRAM.

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The event related potential (ERP) is often measured through the oddball task. On the oddball task, subjects are given “rare stimulus” and “frequent stimulus”. Measured ERPs were analyzed by the averaging technique. In the results, amplitude of the ERP P300 becomes large when the “rare stimulus” is given. However, measured ERPs are included samples without an original feature of ERP. Thus, it is necessary to reject unsuitable measured ERPs when using the averaging technique. In this paper, we propose the rejection method for unsuitable measured ERPs for the averaging technique. Moreover, we combine the proposed method and Woody's adaptive filter method.

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The new periodic binary codes compressed to several sub-pulses are shown. The Doppler characteristics and band-width characteristics are studied by using of MATLAB / Simulink. The results are compared with the characteristics of the M-sequence. It is demonstrated the new periodic binary codes have better these characteristics than M-sequences.

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This paper proposes a Multi-Objective Particle Swarm Optimization (MOPSO) with particle density. In the proposed method, density of particles around every Pareto solution is calculated and a Pareto solution with low particle density is selected as gbest which is a best position visited thus far by all of the particles. Then, it is validated through a simulation with a Multi-Objective 0/1 knapsack problem comparing to the sigma method which is the conventional to select gbest.

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