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[Keyword] CTI(8214hit)

4141-4160hit(8214hit)

  • CQI Feedback Overhead Reduction for Multicarrier MIMO Transmission

    Erlin ZENG  Shihua ZHU  Ming XU  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E91-B No:7
      Page(s):
    2310-2320

    For wideband MIMO-OFDM systems, scheduling and link adaptation are key techniques to improve the throughput performance. However, in systems without reciprocity between the uplink and the downlink channels, these techniques require a high feedback overhead of the channel quality indication (CQI) information. In this paper, we propose a novel CQI feedback reduction method, which is based on the conventional compression techniques exploiting the discrete cosine transformation (DCT). The basic idea is to adaptively permute the CQI sequences of different MIMO streams according to one of the possible patterns before the DCT compression so that the amount of feedback bits is minimized. The possible patterns used are carefully designed according to our analysis of the two types of correlations (the inter-stream correlation and the inter-subband correlation) that exist in MIMO-OFDM transmission, as well as their impact on the compression efficiency. Simulation results verify that the proposed method can effectively reduce the CQI feedback overhead under varying channel conditions.

  • Overtaking Vehicle Detection Method and Its Implementation Using IMAPCAR Highly Parallel Image Processor

    Kazuyuki SAKURAI  Shorin KYO  Shin'ichiro OKAZAKI  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1899-1905

    This paper describes the real-time implementation of a vision-based overtaking vehicle detection method for driver assistance systems using IMAPCAR, a highly parallel SIMD linear array processor. The implemented overtaking vehicle detection method is based on optical flows detected by block matching using SAD and detection of the flows' vanishing point. The implementation is done efficiently by taking advantage of the parallel SIMD architecture of IMAPCAR. As a result, video-rate (33 frames/s) implementation could be achieved.

  • 3D Precise Inspection of Terminal Lead for Electronic Devices by Single Camera Stereo Vision

    Takashi WATANABE  Akira KUSANO  Takayuki FUJIWARA  Hiroyasu KOSHIMIZU  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1885-1892

    It is very important to guarantee the quality of the industrial products by means of visual inspection. In order to reduce the soldering defect with terminal deformation and terminal burr in the manufacturing process, this paper proposes a 3D visual inspection system based on a stereo vision with single camera. It is technically noted that the base line of this single camera stereo was precisely calibrated by the image processing procedure. Also to extract the measuring point coordinates for computing disparity; the error is reduced with original algorithm. Comparing its performance with that of human inspection using industrial microscope, the proposed 3D inspection could be an alternative in precision and in processing cost. Since the practical specification in 3D precision is less than 1 pixel and the experimental performance was around the same, it was demonstrated by the proposed system that the soldering defect with terminal deformation and terminal burr in inspection, especially in 3D inspection, was decreased. In order to realize the inline inspection, this paper will suggest how the human inspection of the products could be modeled and be implemented by the computer system especially in manufacturing process.

  • Robust Small-Object Detection for Outdoor Wide-Area Surveillance

    Daisuke ABE  Eigo SEGAWA  Osafumi NAKAYAMA  Morito SHIOHARA  Shigeru SASAKI  Nobuyuki SUGANO  Hajime KANNO  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1922-1928

    In this paper, we present a robust small-object detection method, which we call "Frequency Pattern Emphasis Subtraction (FPES)", for wide-area surveillance such as that of harbors, rivers, and plant premises. For achieving robust detection under changes in environmental conditions, such as illuminance level, weather, and camera vibration, our method distinguishes target objects from background and noise based on the differences in frequency components between them. The evaluation results demonstrate that our method detected more than 95% of target objects in the images of large surveillance areas ranging from 30-75 meters at their center.

  • Monolithic Gyrators Using Resonant Tunneling Diodes and Application to Active Inductors

    Michihiko SUHARA  Eri UEKI  Tsugunori OKUMURA  

     
    PAPER-Emerging Devices

      Vol:
    E91-C No:7
      Page(s):
    1070-1075

    Monolithic gyrators are proposed on the basis of integrating resonant tunneling diodes (RTDs) and HEMT toward realization of broadband and high-Q passives. Feasibility of millimeter-wave active inductors using the gyrator are described with equivalent circuit analysis and numerical calculations assuming InP based RTDs and a HEMT to be integrated.

  • A Coupled Dynamical Model of Redox Flow Battery Based on Chemical Reaction, Fluid Flow, and Electrical Circuit

    Minghua LI  Takashi HIKIHARA  

     
    PAPER-Nonlinear Problems

      Vol:
    E91-A No:7
      Page(s):
    1741-1747

    The redox (Reduction-Oxidation) flow battery is one of the most promising rechargeable batteries due to its ability to average loads and output of power sources. The transient characteristics are well known as the remarkable feature of the battery. Then it can also compensate for a sudden voltage drop. The dynamics are governed by the chemical reactions, fluid flow, and electrical circuit of its structure. This causes the difficulty of the analysis at transient state. This paper discusses the transient behavior of the redox flow battery based on chemical reactions. The concentration change of vanadium ions depends on the chemical reactions and the flow of electrolysis solution. The chemical reaction rate is restricted by the attached external electric circuit. In this paper, a model of the transient behavior is introduced. The validity of the derived model is examined based on experiments for a tested micro-redox flow battery system.

  • 1.8 V Operation Power Amplifier IC for Bluetooth Class 1 Utilizing p+-GaAs Gate Hetero-Junction FET

    Fumio HARIMA  Yasunori BITO  Hidemasa TAKAHASHI  Naotaka IWATA  

     
    PAPER-GaAs- and InP-Based Devices

      Vol:
    E91-C No:7
      Page(s):
    1104-1108

    We have developed a power amplifier IC for Bluetooth Class 1 operating at single low voltage of 1.8 V for both control and drain voltages. We can realize it due to fully enhancement-mode hetero-junction FETs utilizing a re-grown p +-GaAs gate technology. The power amplifier is a highly compact design as a small package of 1.5 mm1.5 mm0.4 mm with fully integrated gain control and shutdown functions. An impressive power added efficiency of 52% at an output power of 20 dBm is achieved with an associated gain of 22 dB. Also, sufficiently low leakage current of 0.25 µA at 27 is exhibited, which is comparable to conventional HBT power amplifiers.

  • Executable Code Recognition in Network Flows Using Instruction Transition Probabilities

    Ikkyun KIM  Koohong KANG  Yangseo CHOI  Daewon KIM  Jintae OH  Jongsoo JANG  Kijun HAN  

     
    LETTER-Application Information Security

      Vol:
    E91-D No:7
      Page(s):
    2076-2078

    The ability to recognize quickly inside network flows to be executable is prerequisite for malware detection. For this purpose, we introduce an instruction transition probability matrix (ITPX) which is comprised of the IA-32 instruction sets and reveals the characteristics of executable code's instruction transition patterns. And then, we propose a simple algorithm to detect executable code inside network flows using a reference ITPX which is learned from the known Windows Portable Executable files. We have tested the algorithm with more than thousands of executable and non-executable codes. The results show that it is very promising enough to use in real world.

  • Bidirectional Gigabit Millimeter-Wave Wavelength Division Multiplexed-Radio over Fiber Link Using a Reflective Semiconductor Optical Amplifier

    Dae-Won LEE  Yong-Yuk WON  Sang-Kook HAN  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E91-B No:7
      Page(s):
    2418-2421

    We propose a new bidirectional gigabit mm-wave wavelength division multiplexed-radio over fiber link which shares the same wavelength. As the downlink, the central station transmits a 30 GHz single sideband wireless signal which is modulated 1.25 Gbps and also transmits a remote 32 GHz local oscillator for down-conversion of a uplink wireless signal by using a mach-zehnder modulator and a fiber bragg grating. As the uplink, the base station transmits a down-converted 1.25 Gbps wireless signal by using a reflective semiconductor optical amplifier. We achieve a BER < 10-9 in the downlink at -14.05 dBm and uplink at -12.5 dBm after 20 km transmission.

  • Estimating Anomality of the Video Sequences for Surveillance Using 1-Class SVM

    Kyoko SUDO  Tatsuya OSAWA  Kaoru WAKABAYASHI  Hideki KOIKE  Kenichi ARAKAWA  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1929-1936

    We have proposed a method to detect and quantitatively extract anomalies from surveillance videos. Using our method, anomalies are detected as patterns based on spatio-temporal features that are outliers in new feature space. Conventional anomaly detection methods use features such as tracks or local spatio-temporal features, both of which provide insufficient timing information. Using our method, the principal components of spatio-temporal features of change are extracted from the frames of video sequences of several seconds duration. This enables anomalies based on movement irregularity, both position and speed, to be determined and thus permits the automatic detection of anomal events in sequences of constant length without regard to their start and end. We used a 1-class SVM, which is a non-supervised outlier detection method. The output from the SVM indicates the distance between the outlier and the concentrated base pattern. We demonstrated that the anomalies extracted using our method subjectively matched perceived irregularities in the pattern of movements. Our method is useful in surveillance services because the captured images can be shown in the order of anomality, which significantly reduces the time needed.

  • Indexing of Continuously Moving Objects on Road Networks

    Kyoung Soo BOK  Ho Won YOON  Dong Min SEO  Myoung Ho KIM  Jae Soo YOO  

     
    LETTER-Database

      Vol:
    E91-D No:7
      Page(s):
    2061-2064

    In this paper, a new access method is proposed for current positions of moving objects on road networks in order to efficiently update their positions. In the existing index structures, the connectivity of edges is lost because the intersection points in which three or more edges are split. The proposed index structure preserves the network connectivity, which uses intersection oriented network model by not splitting intersection nodes that three or more edges meet for preserving the connectivity of adjacent road segments. The data node stores not only the positions of moving object but also the connectivity of networks.

  • Adaptive MIMO-MLSE Blind Detection in Heterogeneous Stream Transmission for Mobile Radio Communications

    Issei KANNO  Hiroshi SUZUKI  Kazuhiko FUKAWA  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E91-B No:7
      Page(s):
    2346-2356

    This paper proposes a novel MIMO system that introduces a heterogeneous stream (HTS) scheme and a blind signal detection method for mobile radio communications. The HTS scheme utilizes different modulation or coding methods for different MIMO streams, and the blind detection method requires no training sequences for signal separation, detection, and channel estimation. The HTS scheme can remove the ambiguity in identifying separated streams without unique words that are necessary in conventional MIMO blind detection. More specifically, two examples of HTS are considered: modulation type HTS (MHTS) and timing-offset type HTS (THTS). MHTS, which utilizes different modulation constellations with the same bandwidth for different streams, has been previously investigated. This paper proposes THTS which utilizes different transmission timing with the same modulation. THTS can make the blind detection more robust and effective with fractional sampling. The blind joint processing of detection and channel estimation performs adaptive blind MIMO-MLSE and is derived from an adaptive blind MLSE equalizer that employs the recursive channel estimation with the Moore-Penrose generalized inverse. Computer simulations show that the proposed system can achieve superior BER performance with Eb/N0 degradation of 1 dB in THTS and 2.5 dB in MHTS compared with the ideal maximum likelihood detection.

  • Fuzzy Controlled Individual Cell Equalizers for Lithium-Ion Batteries

    Yuang-Shung LEE  Ming-Wang CHENG  Shun-Ching YANG  

     
    PAPER-Energy in Electronics Communications

      Vol:
    E91-B No:7
      Page(s):
    2380-2392

    A fuzzy logic control battery equalizing controller (FLC-BEC) is adopted to control the cell voltage balancing process for a series connected Li-ion battery string. The proposed individual cell equalizer (ICE) is based on the bidirectional Cuk converter operated in the discontinuous capacitor voltage mode (DCVM) to reduce the switching loss and improve equalization efficiency. The ICE with the proposed FLC-BEC can reduce the equalizing time, maintain safe operations during the charge/discharge state and increase the battery string capacity.

  • An Adaptive MIMO-OFDM with Channel Prediction Scheme for Mobile Fading Channels

    Hyundong KIM  Sangho CHOE  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E91-B No:7
      Page(s):
    2443-2446

    We investigate a least squares (LS) based multi-step autoregressive (AR) prediction filter for delay compensation over MIMO channels. We describe the robustness of an adaptive MIMO-OFDM with that filter over mobile fading channels.

  • An Efficient Radio Resource Allocation Scheme for Minimum Outage Probability Using Cooperation in OFDMA Systems

    Junwoo JUNG  Hyungwon PARK  Jae-Sung LIM  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E91-B No:7
      Page(s):
    2321-2330

    Cooperation can increase the system performance by obtaining the spatial diversity. While most of the present works concentrate on the analysis of the cooperation based on the inter-user channel response and developing a scheme for higher cooperative diversity, in this paper, we focus on practical resource allocation in OFDMA systems. Since the user who uses the same center frequency can not receive the signal when transmitting, this constraint should be considered to apply the cooperation to OFDMA systems. In this paper, we propose the pair-based OFDMA frame structure that overcomes this constraint. Also in this frame structure to achieve the minimum outage probability of system, we select the best partner among the candidate neighbors and allocate the suitable subchannels to bandwidth requested users through a cooperative subchannel allocation (CSA) algorithm. In order to evaluate the proposed resource allocation scheme, we carry out simulations based on IEEE 802.16e. The simulation results show that our proposed algorithm offers smaller outage probability than one based on non-cooperative communications and we get the minimum outage probability when a threshold for selection of candidate neighbors is 10 dB. We analyze that these results can be achieved by helping users located around the edge of the cell.

  • A Nonlinear Approach to Robust Routing Based on Reinforcement Learning with State Space Compression and Adaptive Basis Construction

    Hideki SATOH  

     
    PAPER-Nonlinear Problems

      Vol:
    E91-A No:7
      Page(s):
    1733-1740

    A robust routing algorithm was developed based on reinforcement learning that uses (1) reward-weighted principal component analysis, which compresses the state space of a network with a large number of nodes and eliminates the adverse effects of various types of attacks or disturbance noises, (2) activity-oriented index allocation, which adaptively constructs a basis that is used for approximating routing probabilities, and (3) newly developed space compression based on a potential model that reduces the space for routing probabilities. This algorithm takes all the network states into account and reduces the adverse effects of disturbance noises. The algorithm thus works well, and the frequencies of causing routing loops and falling to a local optimum are reduced even if the routing information is disturbed.

  • Neural Prediction of Multidimensional Decisions in Monkey Superior Colliculus Open Access

    Ryohei P. HASEGAWA  Yukako T. HASEGAWA  Mark A. SEGRAVES  

     
    INVITED PAPER

      Vol:
    E91-B No:7
      Page(s):
    2118-2124

    To examine the function of the superior colliculus (SC) in decision-making processes and the application of its single trial activity for "neural mind reading," we recorded from SC deep layers while two monkeys performed oculomotor go/no-go tasks. We have recently focused on monitoring single trial activities in single SC neurons, and designed a virtual decision function (VDF) to provide a good estimation of single-dimensional decisions (go/no-go decisions for a cue presented at a specific visual field, a response field of each neuron). In this study, we used two VDFs for multidimensional decisions (go/no-go decisions at two cue locations) with the ensemble activity which was simultaneously recorded from a small group (4 to 6) of neurons at both sides of the SC. VDFs predicted cue locations as well as go/no-go decisions. These results suggest that monitoring of ensemble SC activity had sufficient capacity to predict multidimensional decisions on a trial-by-trial basis, which is an ideal candidate to serve for cognitive brain-machine interfaces (BMI) such as two-dimensional word spellers.

  • Current Status and Future Prospects of SiC Power JFETs and ICs

    Jian H. ZHAO  Kuang SHENG  Yongxi ZHANG  Ming SU  

     
    INVITED PAPER

      Vol:
    E91-C No:7
      Page(s):
    1031-1041

    This paper will review the development of SiC power devices especially SiC power junction field-effect transistors (JFETs). Rationale and different approaches to the development of SiC power JFETs will be presented, focusing on normally-OFF power JFETs that can provide the highly desired fail-save feature for reliable power switching applications. New results for the first demonstration of SiC Power ICs will be presented and the potential for distributed DC-DC power converters at frequencies higher than 35 MHz will be discussed.

  • Random Texture Defect Detection Using 1-D Hidden Markov Models Based on Local Binary Patterns

    Hadi HADIZADEH  Shahriar BARADARAN SHOKOUHI  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1937-1945

    In this paper a novel method for the purpose of random texture defect detection using a collection of 1-D HMMs is presented. The sound textural content of a sample of training texture images is first encoded by a compressed LBP histogram and then the local patterns of the input training textures are learned, in a multiscale framework, through a series of HMMs according to the LBP codes which belong to each bin of this compressed LBP histogram. The hidden states of these HMMs at different scales are used as a texture descriptor that can model the normal behavior of the local texture units inside the training images. The optimal number of these HMMs (models) is determined in an unsupervised manner as a model selection problem. Finally, at the testing stage, the local patterns of the input test image are first predicted by the trained HMMs and a prediction error is calculated for each pixel position in order to obtain a defect map at each scale. The detection results are then merged by an inter-scale post fusion method for novelty detection. The proposed method is tested with a database of grayscale ceramic tile images.

  • A Low-Complexity Frequency Offset Insensitive Detection for 2.45 GHz LR-WPAN

    Jung-Su HAN  Hyung-Jin CHOI  

     
    PAPER-Transmission Systems and Transmission Equipment for Communications

      Vol:
    E91-B No:7
      Page(s):
    2205-2213

    In this paper, we propose a low-complexity frequency offset insensitive detection method for the 2.45 GHz LR-WPAN demodulator. In IEEE 802.15.4 LR-WPAN (Low-Rate Wireless Personal Area Network) specification, the frequency offset as highest 80 ppm in the 2.45 GHz band is recommended for low-complexity, low-cost, and low-power implementation. The proposed detection method is verified such that the performance is within 2 dB of the optimal coherent detection with low complexity, which is less than half in comparison with conventional detection methods.

4141-4160hit(8214hit)