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[Keyword] plane(179hit)

101-120hit(179hit)

  • Edge-Based Morphological Processing for Efficient and Accurate Video Object Extraction

    Yih-Haw JAN  David W. LIN  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E88-D No:2
      Page(s):
    335-340

    We consider the edge-linking approach for accurate locating of moving object boundaries in video segmentation. We review the existing methods and propose a scheme designed for efficiency and better accuracy. The scheme first obtains a very rough outline of an object by a suitable means, e.g., change detection. It then forms a relatively compact image region that properly contains the object, through a procedure termed "mask sketch." Finally, the outermost edges in the region are found and linked via a shortest-path algorithm. Experiments show that the scheme yields good performance.

  • An Iterative Hyperplane Projection Based Affine Projection Algorithm for Fast Converging Space-Time Adaptive Decision-Directed Equalizer

    Won-Cheol LEE  Chul RYU  Jin-Ho PARK  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E87-B No:12
      Page(s):
    3673-3681

    This paper introduces an efficient affine projection algorithm (APA) using iterative hyperplane projection. The inherent effectiveness against the rank deficient problem has led APA to be the preferred algorithm to be employed for various applications over other variety of fast converging adaptation algorithms. However, the amount of complexity of the conventional APA could not be negligible because of the accomplishment of sample matrix inversion (SMI). Another issue is that the "shifting invariance property," which is typically exploited for single channel case, does not hold ground for space-time decision-directed equalizer (STDE) application deployed in single-input-multi-output (SIMO) systems. Therefore, fast adaptation schemes, such as fast traversal filter based APA (FTF-APA), becomes impossible to utilize. The motivation of this paper deliberates on finding an effective algorithm on the basis of APA, which yields low complexity while sustaining fast convergence as well as excellent tracking ability. The performance of the proposed method is evaluated under wireless SIMO channel in respect to bit error rate (BER) behavior and computational complexity, and upon completion, the validity is confirmed. The performance of the proposed method is evaluated under wireless SIMO channel in respect to bit error rate (BER) behavior and computational complexity, and upon completion, the validity is confirmed.

  • Analysis of Light Wave Propagation in In-Plane Switching Liquid-Crystal Devices by Finite-Difference Time-Domain Method

    Hideo KAWANO  Atsushi MATSUMOTO  Tanroku MIYOSHI  

     
    PAPER-Organic Molecular Electronics

      Vol:
    E87-C No:12
      Page(s):
    2172-2178

    Liquid-crystal devices with in-plane switching electrodes (IPS-LCD) are superior to twisted nematic ones in their wider range of viewing angle, but show serious color shift with viewing angle. The color shift is a phenomenon governed by the three-dimensional orientation of liquid-crystal molecules. In order to evaluate such effects numerically, light wave propagation in the IPS-LCD is studied using a two-dimensional finite-difference time-domain method, where all six components of electromagnetic field are analysed and the three-dimensional properties of liquid-crystal materials are taken into account through the dielectric tensor. The computational space termination is provided by a combination of the uniaxial perfectly matched layer and periodic boundary conditions. It is found for the first time numerically that the color shift effects strongly depend on the asymmetrical profile of liquid-crystal orientation, which is originated from the small pretilt angle.

  • Analysis of Leakage-Inductance Effect on Characteristics of Flyback Converter without Right Half Plane Zero

    Hiroto TERASHI  Tamotsu NINOMIYA  

     
    PAPER-DC/DC Converters

      Vol:
    E87-B No:12
      Page(s):
    3539-3544

    In recent years the size of transformer in a DC-DC converter becomes smaller and thinner for power module type application. It results in the increase of the leakage inductances because the number of turns of the secondary winding becomes smaller. This paper presents the analysis of static and dynamic characteristics of the novel flyback converter proposed before, and clarifies that the transformer's leakage inductances deteriorate the static load regulation, but improve the dynamic stability by increasing the dumping factor.

  • Spatial Correlation Function Analysis of a Dipole Antenna Array in Front of a Ground Plane Reflector for Sectorized Cellular Communications

    Ching-Tai CHIANG  Rong-Ching WU  

     
    LETTER-Antennas and Propagation

      Vol:
    E87-B No:11
      Page(s):
    3394-3397

    This letter develops a practical sectorized antenna array using center-fed half-wavelength dipole antennas that are parallel to and a distance in front of a large ground plane reflector. Each element in the array is designed to provide coverage to isolate each 120sector from adjacent sectors. We derive a closed-form expression for spatial correlation function that can be used as guides in evaluating the effects of array spatial correlation on diversity performance in sectorized cellular communications.

  • Novel Two Step Background Suppression for 2-D LWIR Application

    Doo Hyung WOO  Sang Gu KANG  Hee Chul LEE  

     
    LETTER-Electronic Circuits

      Vol:
    E87-C No:9
      Page(s):
    1649-1651

    A readout circuit involving new two step current mode background suppression is studied for 2-dimensional long wavelength infrared focal plane arrays (LWIR FPA's). Buffered direct injection (BDI) and feedback amplifier structure are adopted for input circuit and background suppression circuit, respectively. The pixel circuit is simple and has very small skimming error less than 0.1%. Enough calibration range over 50% as well as long integration time over 1.75 ms can be obtained using this readout circuit.

  • Availability of Resistive Boundary Condition for Thin Metallic Gratings Placed in Conical Mounting

    Hideaki WAKABAYASHI  Jiro YAMAKITA  Masamitsu ASAI  Hiroshi INAI  

     
    PAPER-Basic Electromagnetic Analysis

      Vol:
    E87-C No:9
      Page(s):
    1560-1567

    The scattering problem by metallic gratings has become one of fundamental problems in electromagnetics. In this paper, a thin metallic grating placed in conical mounting is treated as a lossy dielectric grating expressed by complex permittivity and thickness. The solution of the metallic grating by using the matrix eigenvalue calculations is compared with that of the plane grating by using the resistive boundary condition and the spectral Galerkin procedure, and the availability of the resistive boundary condition for thin metallic gratings in conical mounting is investigated. In order to improve the convergence of the solutions of thin metallic gratings, the spatial harmonics of flux densities which are continuous function instead of electromagnetic fields are used.

  • A Prediction Method of Common-Mode Excitation on a Printed Circuit Board Having a Signal Trace near the Ground Edge

    Tetsushi WATANABE  Hiroshi FUJIHARA  Osami WADA  Ryuji KOGA  Yoshio KAMI  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E87-B No:8
      Page(s):
    2327-2334

    Common-mode excitation caused by an imperfect ground plane on a printed circuit board (PCB) has been conventionally explained with the 'current driven' scheme, in which the common-mode current is driven by the ground voltage across the unintentional inductance of the ground plane. We have developed an alternative method for estimating common-mode excitation that is driven by the difference of the common-mode voltages for two connected transmission lines. A parameter called current division factor (CDF) that represents the degree of imbalance of a transmission line explains the common-mode voltage. In this paper, we calculate the CDF with two-dimensional (2-D) static electric field analysis by using the boundary element method (BEM) for asymmetric transmission lines with an arbitrary cross-section. The proposed 2-D method requires less time than three-dimensional simulations. The EMI increase due to a signal line being close to the edge of the ground pattern was evaluated through CDF calculation. The estimated increase agreed well--within 2 dB--with the measured one.

  • PCB Plane Model Including Frequency-Dependent Losses for Generic Circuit Simulators

    Jonghumn BAEK  Yongjin JEONG  Seokyoon KIM  

     
    LETTER-Electromechanical Devices and Components

      Vol:
    E87-C No:8
      Page(s):
    1388-1394

    This paper proposes a PCB plane model for generic circuit simulators (SPICE). The proposed model reflects two frequency-dependent losses, namely, skin and dielectric losses. Once power/ground plane pair is divided into arrays of unit-cells, each unit-cell is modeled using a transmission line and the loss model. The loss model is composed of a resistor for DC loss, series RL ladder circuit for skin loss and series RC ladder circuit for dielectric loss. To verify the validity of the proposed model, it is compared with SPICE ac analysis using frequency-dependent resistors. Also, we show that the estimation results using the proposed model have a good correlation with that of VNA measurement for the typical PCB stack-up structure of general desktop PCs. With the proposed model, not only ac analysis but also transient analysis can be easily done for circuits including various non-linear/linear devices since the model consists of passive elements only.

  • A Multi-Plane Packet Switch Based on Combined Packet Distribution and Hierarchical Priority Scheduling

    Norihiko MORIWAKI  Hidehiro TOYODA  Masayuki TAKASE  

     
    PAPER-Switching

      Vol:
    E87-B No:7
      Page(s):
    1977-1983

    A large-scale packet-switch architecture for a tera bit/s system--which uses a combined-packet-distribution (CPD) method for a crossbar packet switch--was developed. This method eliminates the restriction on scheduling processing time by extending a switching data unit. The data unit is called a combined packet that consists of plural variable-length packets or their fragments. The combined packets are sequentially distributed among multiple crossbar switch planes and their sequence integrity is preserved. Distributive targets among the switch planes are selectable. As a result, when one or more switch planes are damaged, redundancy of the switch fabric is easily attained in a so-called "graceful degradation" manner. Moreover, this switch uses a novel algorithm called hierarchical priority scheduling. This algorithm enables fairness of scheduling by taking account of queuing state. The repetition required for priority scheduling is reduced by a novel hierarchical approach. The simulated performance of this algorithm shows that it performs better than the simple maximal matching method under both uniform and non-uniform traffic.

  • Arranging Fewest Possible Probes to Detect a Hidden Object with Industrial Application

    Taisuke SHIMAMOTO  Tetsuo ASANO  

     
    PAPER

      Vol:
    E87-A No:5
      Page(s):
    1053-1058

    This paper addresses the problem of arranging fewest possible probes to detect a hidden object in a specified region and presents a reasonable scheme for the purpose. Of special interest is the case where an object is a double-sided conic cylinder which represents the shape of the energy distribution of laser light used in the optical network. The performance of our scheme is evaluated by comparing the number of probes to that of an existing scheme, and our scheme shows a potential for reducing the number of probes. In other words, the time for detection is significantly reduced from a realistic point of view.

  • Sampling Low Significance Bits Image to Reduce Quantized Bit Rate

    Asif HAYAT  Tae-Sun CHOI  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E87-D No:5
      Page(s):
    1276-1279

    The artifacts of low-bit rate quantization in images cannot be removed satisfactorily by known methods. We propose decomposition of images as HSI and LSI (higher- and lower- significance images), followed by subsampling and reconstruction methods for LSI. Experiments show significant improvement in image quality, as compared to other methods.

  • A Fast Codebook Design Algorithm for ECVQ Based on Angular Constraint and Hyperplane Decision Rule

    Ahmed SWILEM  Kousuke IMAMURA  Hideo HASHIMOTO  

     
    PAPER-Image

      Vol:
    E87-A No:3
      Page(s):
    732-739

    In this paper, we propose two fast codebook generation algorithms for entropy-constrained vector quantization. The first algorithm uses the angular constraint to reduce the search area and to accelerate the search process in the codebook design. It employs the projection angles of the vectors to a reference line. The second algorithm has feature of using a suitable hyperplane to partition the codebook and image data. These algorithms allow significant acceleration in codebook design process. Experimental results are presented on image block data. These results show that our new algorithms perform better than the previously known methods.

  • Initialising Cellular Automata in the Hyperbolic Plane

    Kamel CHELGHOUM  Maurice MARGENSTERN  Benot MARTIN  Isabelle PECCI  

     
    PAPER

      Vol:
    E87-D No:3
      Page(s):
    677-686

    In this paper, we investigate how to initialise cellular automata implemented in the hyperbolic plane. We generalise a technique which was indicated in to the case of any rectangular regular grid of the hyperbolic plane. This allows us to construct the initial configuration of any cellular automaton belonging to a rather large class of problems.

  • High Index-Contrast 2D Photonic Band-Edge Laser

    Soon-Hong KWON  Yong-Hee LEE  

     
    INVITED PAPER

      Vol:
    E87-C No:3
      Page(s):
    308-315

    Free-standing 2D slab photonic band-edge lasers based on square lattice and triangular lattice are realized by optical pumping at room-temperature. Both in-plane-emission and surface-emission photonic band-edge lasers are observed and compared. Analyses on optical loss mechanisms for finite-size photonic band-edge lasers are also discussed.

  • Efficient Generation of Plane Triangulations with Specified Maximum Degree

    Hiroyuki TANAKA  Shin-ichi NAKANO  

     
    PAPER

      Vol:
    E87-D No:2
      Page(s):
    330-336

    A "based" plane triangulation is a plane triangulation with one designated edge on the outer face. In this paper we give a simple algorithm to generate all biconnected based plane triangulations having exactly n vertices and with the maximum degree exactly D. The algorithm uses O(n) space and generates such triangulations in O(1) time per triangulation without duplications.

  • Sputtering Conditions and Properties of In-Plane-Aligned Y-Ba-Cu-O Films for Devices Application

    Lan ZHANG  Masataka MORIYA  Tadayuki KOBAYASHI  Masashi MUKAIDA  Toshinari GOTO  

     
    PAPER

      Vol:
    E87-C No:2
      Page(s):
    202-205

    In-plane-aligned a-axis-oriented YBa2Cu3O7-δ (YBCO) thin films are attractive for the formation of planar intrinsic Josephson devices. In this study, these films were deposited by dc sputtering on LaSrGaO4 (LSGO) (100) substrates and the dependence of the characteristics on the deposition conditions was investigated. In-plane-aligned a-axis-oriented YBCO thin films were successfully grown in the substrate temperature range of 555-615. With the temperature gradient method, it was seen that the critical temperature of the film increased to 81 K. The current-voltage characteristic along the c-axis exhibited clear multibranch structures. These results indicate that ion-cleaning of the substrate surface broadens the growth temperature range of these films and planar intrinsic Josephson devices can be fabricated from these films.

  • Algorithms for Drawing Plane Graphs

    Takao NISHIZEKI  Kazuyuki MIURA  Md. Saidur RAHMAN  

     
    INVITED SURVEY PAPER

      Vol:
    E87-D No:2
      Page(s):
    281-289

    Graph drawing addresses the problem of constructing geometric representation of information and finds applications in almost every branch of science and technology. Efficient algorithms are essential for automatic drawings of graphs, and hence a lot of research has been carried out in the last decade by many researchers over the world to develop efficient algorithms for drawing graphs. In this paper we survey the recent algorithmic results on various drawings of plane graphs: straight line drawing, convex drawing, orthogonal drawing, rectangular drawing and box-rectangular drawing.

  • Three-Dimensional Eye Movement Simulator Extracting Instantaneous Eye Movement Rotation Axes, the Plane Formed by Rotation Axes, and Innervations for Eye Muscles

    Kanae NAOI  Koji NAKAMAE  Hiromu FUJIOKA  Takao IMAI  Kazunori SEKINE  Noriaki TAKEDA  Takeshi KUBO  

     
    PAPER-Medical Engineering

      Vol:
    E86-D No:11
      Page(s):
    2452-2462

    We have developed a three-dimensional eye movement simulator that simulates eye movement. The simulator allows us to extract the instantaneous eye movement rotation axes from clinical data sequences. It calculates the plane formed by rotation axes and displays it on an eyeball with rotation axes. It also extracts the innervations for eye muscles. The developed simulator is mainly programmed by a CG programming language, OpenGL. First, the simulator was applied to saccadic eye movement data in order to show the so-called Listing's plane on which all hypothetical rotation axes lie. Next, it was applied to clinical data sequences of two patients with benign paroxysmal positional vertigo (BPPV). Instantaneous actual rotation axes and innervations for eye muscle extracted from data sequences have special characteristics. These results are useful for the elucidation of the mechanism of vestibular symptoms, particularly vertigo.

  • Experimental Analysis on GMPLS-Based Photonic Switching Networks

    Michiaki HAYASHI  Tomohiro OTANI  Hideaki TANAKA  Masatoshi SUZUKI  

     
    PAPER

      Vol:
    E86-B No:8
      Page(s):
    2327-2333

    Implementation issues on generalized multi-protocol label switching (GMPLS) -based photonic switching networks are experimentally analyzed. A resilient control plane architecture using in-fiber and out-of-fiber control channels is proposed to resolve issues of establishing the control plane in out-of-band networks. The resilient control plane is demonstrated in a photonic cross-connect (PXC) -based GMPLS network involving a 1,000 km transmission line. Fast signaling for provisioning and restoration operation is accomplished by implementing in-fiber control channels as primary, and the out-of-fiber control channels effectively operate as secondary and restore messaging of the control information between neighbors. The control channel protection is initiated by the link management protocol (LMP). Using the test bed, optical layer routing operation is investigated to assess the effects on the signal quality of wavelength paths, and transparent routing of the wavelength paths over one-hop and two-hops route is demonstrated within 1 dB difference regarding the Q factor. Stable operation of loss of light (LOL) -triggered restoration is demonstrated by setting the optical level threshold 5 dB higher than the amplified spontaneous emission (ASE) noise level.

101-120hit(179hit)