The search functionality is under construction.
The search functionality is under construction.

Keyword Search Result

[Keyword] (42807hit)

12461-12480hit(42807hit)

  • Connection Setup Signaling Scheme with Flooding-Based Path Searching for Diverse-Metric Network

    Ko KIKUTA  Daisuke ISHII  Satoru OKAMOTO  Eiji OKI  Naoaki YAMANAKA  

     
    PAPER-Network

      Vol:
    E95-B No:8
      Page(s):
    2600-2609

    Connection setup on various computer networks is now achieved by GMPLS. This technology is based on the source-routing approach, which requires the source node to store metric information of the entire network prior to computing a route. Thus all metric information must be distributed to all network nodes and kept up-to-date. However, as metric information become more diverse and generalized, it is hard to update all information due to the huge update overhead. Emerging network services and applications require the network to support diverse metrics for achieving various communication qualities. Increasing the number of metrics supported by the network causes excessive processing of metric update messages. To reduce the number of metric update messages, another scheme is required. This paper proposes a connection setup scheme that uses flooding-based signaling rather than the distribution of metric information. The proposed scheme requires only flooding of signaling messages with requested metric information, no routing protocol is required. Evaluations confirm that the proposed scheme achieves connection establishment without excessive overhead. Our analysis shows that the proposed scheme greatly reduces the number of control messages compared to the conventional scheme, while their blocking probabilities are comparable.

  • Bit-Error and Soft-Error Resilient 7T/14T SRAM with 150-nm FD-SOI Process

    Shusuke YOSHIMOTO  Takuro AMASHITA  Shunsuke OKUMURA  Koji NII  Masahiko YOSHIMOTO  Hiroshi KAWAGUCHI  

     
    PAPER-Reliability, Maintainability and Safety Analysis

      Vol:
    E95-A No:8
      Page(s):
    1359-1365

    This paper presents measurement results of bit error rate (BER) and soft error rate (SER) improvement on 150-nm FD-SOI 7T/14T (7-transistor/ 14-transistor) SRAM test chips. The reliability of the 7T/14T SRAM can be dynamically changed by a control signal depending on an operating condition and application. The 14T dependable mode allocates one bit in a 14T cell and improves the BER in a read operation and SER in a retention state, simultaneously. We investigate its error rate mitigating mechanisms using Synopsys TCAD simulator. In our measurements, the minimum operating voltage was improved by 100 mV, the alpha-induced SER was suppressed by 80.0%, and the neutron-induced SER was decreased by 34.4% in the 14T dependable mode over the 7T normal mode.

  • Pedestrian Detection Using Gradient Local Binary Patterns

    Ning JIANG  Jiu XU  Satoshi GOTO  

     
    PAPER-Coding & Processing

      Vol:
    E95-A No:8
      Page(s):
    1280-1287

    In recent years, local pattern based features have attracted increasing interest in object detection and recognition systems. Local Binary Pattern (LBP) feature is widely used in texture classification and face detection. But the original definition of LBP is not suitable for human detection. In this paper, we propose a novel feature named gradient local binary patterns (GLBP) for human detection. In this feature, original 256 local binary patterns are reduced to 56 patterns. These 56 patterns named uniform patterns are used for generating a 56-bin histogram. And gradient value of each pixel is set as the weight which is always same in LBP based features in histogram calculation to computing the values in 56 bins for histogram. Experiments are performed on INRIA dataset, which shows the proposal GLBP feature is discriminative than histogram of orientated gradient (HOG), Semantic Local Binary Patterns (S-LBP) and histogram of template (HOT). In our experiments, the window size is fixed. That means the performance can be improved by boosting methods. And the computation of GLBP feature is parallel, which make it easy for hardware acceleration. These factors make GLBP feature possible for real-time pedestrian detection.

  • A New First-Scan Method for Two-Scan Labeling Algorithms

    Lifeng HE  Yuyan CHAO  Kenji SUZUKI  

     
    LETTER-Pattern Recognition

      Vol:
    E95-D No:8
      Page(s):
    2142-2145

    This paper proposes a new first-scan method for two-scan labeling algorithms. In the first scan, our proposed method first scans every fourth image line, and processes the scan line and its two neighbor lines. Then, it processes the remaining lines from top to bottom one by one. Our method decreases the average number of times that must be checked to process a foreground pixel will; thus, the efficiency of labeling can be improved.

  • Prospective for Gallium Nitride-Based Optical Waveguide Modulators

    Arnaud STOLZ  Laurence CONSIDINE  Elhadj DOGHECHE  Didier DECOSTER  Dimitris PAVLIDIS  

     
    PAPER-GaN-based Devices

      Vol:
    E95-C No:8
      Page(s):
    1363-1368

    A complete analysis of GaN-based structures with very promising characteristics for future optical waveguide devices, such as modulators, is presented. First the material growth was optimized for low dislocation density and surface roughness. Optical measurements demonstrate excellent waveguide properties in terms of index and temperature dependence while planar propagation losses are below 1 dB/cm. Bias was applied on both sides of the epitaxially grown films to evaluate the refractive index dependence on reverse voltage and a variation of 2.10-3 was found for 30 V. These results support the possibility of using structures of this type for the fabrication of modulator devices such as Mach-Zehnder interferometers.

  • Iterative Learning Control with Advanced Output Data for an Unknown Number of Non-minimum Phase Zeros

    Gu-Min JEONG  Chanwoo MOON  Hyun-Sik AHN  

     
    LETTER-Systems and Control

      Vol:
    E95-A No:8
      Page(s):
    1416-1419

    This letter investigates an iterative learning control with advanced output data (ADILC) scheme for non-minimum phase (NMP) systems when the number of NMP zeros is unknown. ADILC has a simple learning structure that can be applied to both minimum phase and NMP systems. However, in the latter case, it is assumed that the number of NMP zeros is already known. In this paper, we propose an ADILC scheme in which the number of NMP zeros is unknown. Based on input-to-output mapping, the learning starts from the relative degree. When the input becomes larger than a certain upper bound, we redesign the input update law which consists of the relative degree and the estimated value for the number of NMP zeros.

  • Hybrid Resource Allocation Scheme with Proportional Fairness in OFDMA-Based Cognitive Radio Systems

    Li LI  Changqing XU  Pingzhi FAN  Jian HE  

     
    LETTER-Communication Theory and Signals

      Vol:
    E95-A No:8
      Page(s):
    1430-1434

    In this paper, the resource allocation problem for proportional fairness in hybrid Cognitive Radio (CR) systems is studied. In OFDMA-based CR systems, traditional resource allocation algorithms can not guarantee proportional rates among CR users (CRU) in each OFDM symbol because the number of available subchannels might be smaller than that of CRUs in some OFDM symbols. To deal with this time-varying nature of available spectrum resource, a hybrid CR scheme in which CRUs are allowed to use subchannels in both spectrum holes and primary users (PU) bands is adopted and a resource allocation algorithm is proposed to guarantee proportional rates among CRUs with no undue interference to PUs.

  • Hybrid Analysis of Radar Cross Section of Open-Ended Cavity Scatterers by Using Modified Physical Optics and Iterative Physical Optics

    Ryosuke HASABA  Makoto ANDO  

     
    PAPER-Electromagnetic Theory

      Vol:
    E95-C No:8
      Page(s):
    1399-1405

    Electromagnetic scattering at high-frequencies is computationally heavy. Radar cross section (RCS) of electrically large concave and convex objects are solved by using the hybrid method. For convex and concave surfaces, Modified-Vector Physical Optics (MPO) with enhanced accuracy and Iterative Physical Optics (IPO) taking multiple-reflections into account, are selectively and independently applied for convex and concave parts of the scatterer. The accuracy of RCS by this hybrid method is tested with the MoM based simulator Wipl-D as the reference. The RCS from relatively small scatterers with the dimension of the order of a few wavelengths can be successfully predicted.

  • Asymmetric Learning Based on Kernel Partial Least Squares for Software Defect Prediction

    Guangchun LUO  Ying MA  Ke QIN  

     
    LETTER-Software Engineering

      Vol:
    E95-D No:7
      Page(s):
    2006-2008

    An asymmetric classifier based on kernel partial least squares is proposed for software defect prediction. This method improves the prediction performance on imbalanced data sets. The experimental results validate its effectiveness.

  • An Enhanced Secure Authentication Scheme with Anonymity for Wireless Environments

    Woongryul JEON  Jeeyeon KIM  Junghyun NAM  Youngsook LEE  Dongho WON  

     
    LETTER-Terrestrial Wireless Communication/Broadcasting Technologies

      Vol:
    E95-B No:7
      Page(s):
    2505-2508

    As anonymity increasingly becomes a necessary and legitimate aim in many applications, a number of anonymous authentication schemes have been suggested over the years. Among the many schemes is Lee and Kwon's password-based authentication scheme for wireless environments. Compared with previous schemes, Lee and Kwon's scheme not only improves anonymity by employing random temporary IDs but also provides user-friendliness by allowing human-memorable passwords. In this letter, we point out that Lee and Kwon's scheme, despite its many merits, is vulnerable to off-line password guessing attacks and a forgery attack. In addition, we show how to eliminate these vulnerabilities.

  • Secret Sharing Schemes from Linear Codes over Finite Rings

    Jianfa QIAN  Wenping MA  

     
    LETTER-Cryptography and Information Security

      Vol:
    E95-A No:7
      Page(s):
    1193-1196

    An important concept in secret sharing scheme is the access structure. However, determining the access structure of the secret sharing scheme based on a linear code is a very difficult problem. In this work, we provide a method to construct a class of two-weight linear codes over finite rings. Based on the two-weight codes, we present an access structure of a secret sharing scheme.

  • Discriminative Textural Features for Image and Video Colorization

    Michal KAWULOK  Jolanta KAWULOK  Bogdan SMOLKA  

     
    PAPER-Image Synthesis

      Vol:
    E95-D No:7
      Page(s):
    1722-1730

    Image colorization is a semi-automatic process of adding colors to monochrome images and videos. Using existing methods, required human assistance can be limited to annotating the image with color scribbles or selecting a reference image, from which the colors are transferred to a source image or video sequence. In the work reported here we have explored how to exploit the textural information to improve this process. For every scribbled image we determine the discriminative textural feature domain. After that, the whole image is projected onto the feature space, which makes it possible to estimate textural similarity between any two pixels. For single image colorization based on a set of color scribbles, our contribution lies in using the proposed feature space domain rather than the luminance channel. In case of color transfer used for colorization of video sequences, the feature space is generated based on a reference image, and textural similarity is used to match the pixels between the reference and source images. We have conducted extensive experimental validation which confirmed the importance of using textural information and demonstrated that our method significantly improves colorization result.

  • Precoder Design and Capacity Analysis for Multi-Antenna Full-Duplex Relay

    Young-Woo KWAK  Jong-Ho LEE  Yong-Hwa KIM  Seong-Cheol KIM  

     
    LETTER-Fundamental Theories for Communications

      Vol:
    E95-B No:7
      Page(s):
    2446-2450

    In this letter, a precoding design for a multiple-input multiple-output (MIMO) full-duplex relay (FDR) system is proposed. For this system, mitigating the self-interference imposed by the transmit antennas on the receive antennas in the same relay station is crucial for improving the performance of the FDR system. The precoding scheme designed in this study uses block-diagonalization (BD). Using this precoding scheme, FDR capacity analysis is performed in the MIMO downlink relay system. Numerical results on system performance in terms of capacity are shown and discussed.

  • Localization of Passive RFID Tags by Using Broad-Type Multi-Sensing-Range (B-MSR) Method

    Manato FUJIMOTO  Tomotaka WADA  Atsuki INADA  Emi NAKAMORI  Yuki ODA  Kouichi MUTSUURA  Hiromi OKADA  

     
    PAPER-Measurement Technology

      Vol:
    E95-A No:7
      Page(s):
    1164-1174

    The radio frequency identification (RFID) system has attracting attention as a new identification source that achieves a ubiquitous environment. Each RFID tag has a unique ID code, and is attached on an object whose information it contains. A user reads the unique ID code using RFID readers and obtains information about the object. One of the important applications of RFID technology is the indoor position estimation of RFID tags. It can be applied to navigation systems for people in complex buildings. In this paper, we propose an effective position estimation method named Broad-type Multi-Sensing-Range (B-MSR) method to improve the estimation error of the conventional methods using sensor model. A new reader antenna with two flexible antenna elements is introduced into B-MSR. The distance between two flexible antenna elements can be adjusted. Thus, two kinds of system parameters can be controlled, the distance between two antenna elements and the transmission power of the RFID reader. In this paper, four sensing ranges are settled by controlling the values of two parameters. The performance evaluation shows four characteristics of B-MSR. Firstly, it reduces the initial estimation error. Secondly, it reduces the moving distance. Thirdly, it reduces the number of different sensing points. Fourthly, it shortens the required estimation time.

  • Suppression of Polarization Dependent Loss by Using a Single Birefringent Fiber for Low-Coherence Signal

    Mitsuhiro TATEDA  Kei OZAWA  

     
    PAPER-Fiber-Optic Transmission for Communications

      Vol:
    E95-B No:7
      Page(s):
    2302-2305

    Some optical components have polarization dependent loss (PDL), which degrades the performance of optical measurement systems. Various PDL suppression methods have been proposd, most of them have rather complicated structures. In this paper we propose a new simple method for PDL suppression, in which a single birefringent element is concatenated to a PDL device with their birefringent axes offset by π/4. The effectiveness of the proposed method is verified by experiments, that is, polarization dependent loss variation amplitude V of a device relative to its average loss is reduced from 90% to 2% by using a 2 m long PANDA fiber for an LED light source whose central wavelength λ0 and spectral width Δλ are 847 nm and 55 nm, respectively. Furthermore, for an SLD light source with λ0=1539 nm and Δλ=71 nm, V as much as 80% is reduced to 2% by using the same PANDA fiber.

  • ML Frame Synchronization for OFDM Systems Using a Known Pilot and Cyclic Prefixes

    Heon HUH  

     
    PAPER-Transmission Systems and Transmission Equipment for Communications

      Vol:
    E95-B No:7
      Page(s):
    2296-2301

    Orthogonal frequency-division multiplexing (OFDM) is a popular air interface technology that is adopted as a standard modulation scheme for 4G communication systems owing to its excellent spectral efficiency. For OFDM systems, synchronization problems have received much attention along with peak-to-average power ratio (PAPR) reduction. In addition to frequency offset estimation, frame synchronization is a challenging problem that must be solved to achieve optimal system performance. In this paper, we present a maximum likelihood (ML) frame synchronizer for OFDM systems. The synchronizer exploits a synchronization word and cyclic prefixes together to improve the synchronization performance. Numerical results show that the performance of the proposed frame synchronizer is better than that of conventional schemes. The proposed synchronizer can be used as a reference for evaluating the performance of other suboptimal frame synchronizers. We also modify the proposed frame synchronizer to reduce the implementation complexity and propose a near-ML synchronizer for time-varying fading channels.

  • Real-Time Counting People in Crowded Areas by Using Local Empirical Templates and Density Ratios

    Dao-Huu HUNG  Gee-Sern HSU  Sheng-Luen CHUNG  Hideo SAITO  

     
    PAPER-Recognition

      Vol:
    E95-D No:7
      Page(s):
    1791-1803

    In this paper, a fast and automated method of counting pedestrians in crowded areas is proposed along with three contributions. We firstly propose Local Empirical Templates (LET), which are able to outline the foregrounds, typically made by single pedestrians in a scene. LET are extracted by clustering foregrounds of single pedestrians with similar features in silhouettes. This process is done automatically for unknown scenes. Secondly, comparing the size of group foreground made by a group of pedestrians to that of appropriate LET captured in the same image patch with the group foreground produces the density ratio. Because of the local scale normalization between sizes, the density ratio appears to have a bound closely related to the number of pedestrians who induce the group foreground. Finally, to extract the bounds of density ratios for groups of different number of pedestrians, we propose a 3D human models based simulation in which camera viewpoints and pedestrians' proximity are easily manipulated. We collect hundreds of typical occluded-people patterns with distinct degrees of human proximity and under a variety of camera viewpoints. Distributions of density ratios with respect to the number of pedestrians are built based on the computed density ratios of these patterns for extracting density ratio bounds. The simulation is performed in the offline learning phase to extract the bounds from the distributions, which are used to count pedestrians in online settings. We reveal that the bounds seem to be invariant to camera viewpoints and humans' proximity. The performance of our proposed method is evaluated with our collected videos and PETS 2009's datasets. For our collected videos with the resolution of 320 × 240, our method runs in real-time with good accuracy and frame rate of around 30 fps, and consumes a small amount of computing resources. For PETS 2009's datasets, our proposed method achieves competitive results with other methods tested on the same datasets [1],[2].

  • An Improved GPS/RFID Integration Method Based on Sequential Iterated Reduced Sigma Point Kalman Filter

    Jing PENG  Falin WU  Ming ZHU  Feixue WANG  Kefei ZHANG  

     
    PAPER-Navigation, Guidance and Control Systems

      Vol:
    E95-B No:7
      Page(s):
    2433-2441

    In this paper, an improved GPS/RFID integration method based on Sequential Iterated Reduced Sigma Point Kalman Filter (SIRSPKF) is proposed for vehicle navigation applications. It is applied to improve the accuracy, reliability and availability of satellite positioning in the areas where the satellite visibility is limited. An RFID system is employed to assist the GPS system in achieving high accuracy positioning. Further, to reduce the measurement noise and decrease the computational complexity caused by the integrated GPS/RFID, SIRSPKF is investigated as the dominant filter for the proposed integration. Performances and computational complexities of different integration scenarios with different filters are compared in this paper. A field experiment shows that both accuracy and availability of positioning can be improved significantly by this low-cost GPS/RFID integration method with the reduced computational load.

  • DISWOP: A Novel Scheduling Algorithm for Data-Intensive Workflow Optimizations

    Yuyu YUAN  Chuanyi LIU  Jie CHENG  Xiaoliang WANG  

     
    PAPER-Fundamentals of Information Systems

      Vol:
    E95-D No:7
      Page(s):
    1839-1846

    Execution performance is critical for large-scale and data-intensive workflows. This paper proposes DISWOP, a novel scheduling algorithm for data-intensive workflow optimizations; it consists of three main steps: workflow process generation, task & resource mapping, and task clustering. To evaluate the effectiveness and efficiency of DISWOP, a comparison evaluation of different workflows is conducted a prototype workflow platform. The results show that DISWOP can speed up execution performance by about 1.6-2.3 times depending on the task scale.

  • Research on Characteristics of Field Uniformity in Reverberation Chamber Using Two TX Antennas

    Jung-Hoon KIM  Tae-Heon JANG  Sung-Kuk LIM  Songjun LEE  Sung-Il YANG  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E95-B No:7
      Page(s):
    2386-2392

    This paper presents a method to improve field uniformity using two TX antennas in a reverberation chamber with less steps of a stirrer. A mode-stirred reverberation chamber (MSRC) is considered as an alternative to the semi-anechoic chamber for an electromagnetic compatibility test because it provides a large test volume, a statistically uniform field, and a high maximum electric field. To improve field uniformity, we introduce two transmitting antennas for excitation in an MSRC, and predict statistical distribution of the complex reflection coefficients (scattering parameters). To prove the validation of our theory and the reliability of measurement results, three kinds of stirrers with different shape and sizes were fabricated and their efficiencies were measured in an MSRC, and then field uniformities have been investigated for 1–3 GHz frequency within the maximum number of independent samples that stirrers can provide. The measurement results show that the average received power is about 1.5 times as high as when using one transmitting antenna, and field uniformity is improved. Use of two transmitting antennas in an MSRC is regarded as a useful method to improve field uniformity at less stirrer steps, for radiated immunity tests.

12461-12480hit(42807hit)