The La_0.5Sr_0.5CoO₃ was used as a cathode for the first time when the plasma display panel was used on the handheld personal computer. It has favorable sputtering resistance characteristic and stable discharge characteristic in gases. A cathode made from the La_0.5Sr_0.5CoO₃ has unique electrical characteristic in period of continual discharge.
The discharge voltage and luminance of the La_0.5Sr_0.5CoO₃ shift during an extended period of discharge, and the discharge voltage continue to increase in later period of continual discharge. In this report, the discharge and luminescence area shift of the La_0.5Sr_0.5CoO₃ were investigated through an analysis of the DC plasma panel which was made as prototype. It is presumed that the discharge voltage and luminance shift is caused by the discharge and luminance area shift of the cathode surface, and that the current density shift is caused by the discharge area constriction in later periods of continual discharge. In order to find out this mechanism, the discharge and luminance area shift process of the cathode surface were examined by using a model.

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Overvoltage induced by surge currents due to thunderstorm lightnings causes harmful breakdown troubles of CATV communication equipment installed in and with power distribution systems. In this paper, the origin and natures of surge currents, their invading route into the system, and the system components such as earth impedances affecting over voltages are studied. Transient analyses are then performed using an equivalent circuit to evaluate over voltages. Application of the obtained results to the field fault data of communication equipment and possible protection method of them are discussed.

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Coexistence method when various different type PLC (Power Line Communication) systems exist on the same electric power line is not so considered though these systems have already been used. In this paper, we will propose the different system detection method in the environment like above-mentioned and a common wideband control signal with the robustness to be able to communicate each other even in some harsh environments of the electric power line. Therefore a plural of different type systems can coexist even when those systems are used on the same electric power line because of using the common wideband signal for the proposed different system detection method. For example, power line channel is divided into a control region and a data transmission region with the synchronized timing of AC zero crossing in the proposed method. The proposed common wideband signal is used in order to allocate each communication band for each different type system in the control region. In the computer simulation, several carrier detection probabilities were calculated in AWGN (Added White Gaussian Noise) channel and the 80 simulated channels based on the channel data which were measured in the U.S. These results show that the proposed control signal for the different system detection method is robust enough to use in the power line.

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We have proposed the pipe-based transmission system, which uses refrigerant pipe of the multi air-conditioner, and can expand the wireless communication system confined within a room space into the communication system applicable to the whole building. In this paper, EMC characteristics of the Refrigerant pipe-based transmission line, such as LCL (Longitudinal Conversion Loss) and leaked electric field, are calculated by using the method of moment, and it is clear that the calculation values of the EMC characteristics almost agreed with measurement values. Furthermore, it is suggested by computer simulation of the real scale model that the pipe based transmission system has possibility to comply with the EMI regulation specified by the electrical appliance and material safety law in Japan.

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Supporting multimedia applications over wireless networks has become a very active research topic recently because video applications are prognosticated to receive high demand in future wireless networks, such as ad hoc networks. However, enabling video transmission over wireless ad hoc networks is more challenging than over other wireless networks due to the node mobility, interference and the lack of infrastructure. This paper addresses the problem of video transmission over ad hoc networks. We propose to combine Multiple Description Coding (MDC) with multiple source transport (Multipoint-to-Point transfer: MP2P) in order to maintain a smooth video streaming over wireless ad hoc networks. In this paper, we perform comprehensive simulation and test bed experiment in order to show the effect of the proposed MP2P video transfer with MDC for two description case on video streaming over wireless ad hoc networks. The results show that the proposed mechanism successfully improves the video transfer performance in terms of video packet reachability and throughput.

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In recent years, many human tracking researches have been proposed in order to analyze human dynamic trajectory. These researches are general technology applicable to various fields, such as customer purchase analysis in a shopping environment and safety control in a (railroad) crossing. In this paper, we present a new approach for tracking human positions by stereo image. We use the framework of two-stepped clustering with k-means method and fuzzy clustering to detect human regions. In the initial clustering, k-means method makes middle clusters from objective features extracted by stereo vision at high speed. In the last clustering, c-means fuzzy method cluster middle clusters based on attributes into human regions. Our proposed method can be correctly clustered by expressing ambiguity using fuzzy clustering, even when many people are close to each other. The validity of our technique was evaluated with the experiment of trajectories extraction of doctors and nurses in an emergency room of a hospital.

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In this paper, we propose a real-time tracking method for driver's head pose in real vehicle environment by using multiple NIR cameras. In order to achieve real-time performance and high-accuracy, 6-DOF of head pose is estimated by a particle filter with restricted state space. Firstly, the 3D position of nose hole is measured by template matching of stereo images. Because nose hole is the most dark area in the captured NIR images, we can robustly detect the position of the nose very precisely. From the 3D position of the nose, we can estimate the head pose as an initial estimate. Then, each hypothesis is updated by prior probability with a constraint of nose position. Thus it can reduce the number of particles with maintained accuracy. The experimental results indicate that this method is effective for head pose tracking.

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Recent studies have been mainly engaged with movements by 2 or more autonomous robots.
Especially, the development of autonomous robots utilized by the industrial manufacture has been advancing.
However, the extent of these researches was limited to robots moving in 3 dimensional autonomous robots, such as airplanes or helicopters.
On the other hand, regarding studies on small size indoor 3 dimensional blimp robots, characteristics of entertainment robots, indoor surveillance robots, object searching robots in disaster building have been subject to investigation.
However, previous studies drew the attention to the difficulties arising when the cooperative behavior of 2 or more autonomous blimp robots is strongly presented depending on changes in the experimental environment, denoting the weak points of these systems.
In this paper, 2 small size autonomous blimp robots were used, and basic experiments with time constraints of behavior control were conducted, examining possible coordinated movements of 2 small size autonomous blimp robots, for the purpose of high application achievement of utility.

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Genetic Network Programming (GNP) is an evolutionary algorithm which represents its solutions using graph structures. Since GNP can create quite compact programs and has an implicit memory function, GNP works well especially in dynamic environments. In addition, a study on creating trading rules on stock markets using GNP with Importance Index (GNP-IMX) has been done. IMX is one of the criterions for decision making. However, the values of IMXs must be deteminined by our experience/knowledge. Therefore in this paper, IMXs are adjusted appropriately during the stock trading in order to predict the rise and fall of the stocks. Moreover, newly defined flag nodes are introduced to GNP, which can appropriately judge the current situation of the stock prices, and also contributes to the use of many kinds of nodes in GNP program. In the simulation, programs are evolved using the stock prices of 20 companies. Then the generalization ability is tested and compared with GNP without flag nodes, GNP without IMX adjustment and Buy&Hold.

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Information about customers in shops plays an important role in marketing analysis. Currently, in convenience stores and supermarkets, the identification of customer's gender is examined by clerks. On the other hand, gender identification systems using camera images are investigated. However, these systems have a problem of invading human privacies in identifying attributes of customers. The proposed system identifies gender by using infrared area scanners and Bayesian network. In the proposed system, since infrared area scanners do not take customers' images directly, invasion of privacies are not occurred. The proposed method uses three parameters of height, walking speed and pace for humans. In general, it is shown that these parameters have factors of sexual distinction in humans, and Bayesian network is designed with these three parameters. The proposed method resolves the existent problems of restricting the locations where the systems are set and invading human privacies. Experimental results using data obtained from 450 people show that the identification rate for the proposed method was 91.3% on the average of both of male and female identifications.

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A genetic programming (GP) method which synthesizes one-port circuits from a given frequency characteristic is proposed. Especially it is precisely described how to synthesize multiple equivalent circuits which have the same characteristic by the relay-search type GP(RS-GP) and are useful for users' choices. It is necessary to consider distances between tree structures which express individuals and the SSPD(Strongly Structure Preserving Distance) based on SSPM(Strongly Structure Preserving Mapping) is utilized as metric measures. The multiway tree structure with equivalent simplification operations is proposed to have one-to-one correspondence between a tree and a circuit. A circuit synthesis which has a given impedance frequency-characteristic is adopted as an example. According to the conventional analytical method, four types of circuits can be easily synthesized; a series, a parallel, and two ladder circuits. All of them are synthesized by the proposed method. Furthermore other new circuits are synthesized.

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Three types of switching power supply, which are buck, boost, buck/boost converter, are statically and dynamically analysed. A framework of large signal analysis presents characteristics of converters which vary with operating points, and discusses a relationship between statics and dynamics. It is shown that boost and buck/boost converters substantially change their characteristics. There exists the operating points where for low frequencies the phases become -90° or -180° and the gains fall off to low values. The phenomenon is characterized by a zero of transfer function of the converter and also by the statics.

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