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2041-2060hit(5900hit)

  • Online Continuous Scale Estimation of Hand Gestures

    Woosuk KIM  Hideaki KUZUOKA  Kenji SUZUKI  

     
    PAPER-Human-computer Interaction

      Vol:
    E95-D No:10
      Page(s):
    2447-2455

    The style of a gesture provides significant information for communication, and thus understanding the style is of great importance in improving gestural interfaces using hand gestures. We present a novel method to estimate temporal and spatial scale—which are considered principal elements of the style—of hand gestures. Gesture synchronization is proposed for matching progression between spatio-temporally varying gestures, and scales are estimated based on the progression matching. For comparing gestures of various sizes and speeds, gesture representation is defined by adopting turning angle representation. Also, LCSS is used as a similarity measure for reliability and robustness to noise and outliers. Performance of our algorithm is evaluated with synthesized data to show the accuracy and robustness to noise and experiments are carried out using recorded hand gestures to analyze applicability under real-world situations.

  • A General Construction of Low Correlation Zone Sequence Sets Based on Finite Fields and Balanced Function

    Huijuan ZUO  Qiaoyan WEN  Xiuwen MA  Jie ZHANG  

     
    LETTER-Cryptography and Information Security

      Vol:
    E95-A No:10
      Page(s):
    1792-1795

    In this letter, we present a general construction of sequence sets with low correlation zone, which is based on finite fields and the balance property of some functions. The construction is more flexible as far as the partition of parameters is concerned. A simple example is also given to interpret the construction.

  • An Efficient Synchronization Scheme for Cooperative WBAN in Wireless Medical Telemetry Systems

    Sekchin CHANG  

     
    LETTER

      Vol:
    E95-B No:10
      Page(s):
    3096-3099

    In this letter, a timing synchronization scheme is proposed for cooperative WBAN which can be utilized in wireless medical telemetry systems. The approach efficiently exploits the cyclic structure of a presented preamble in order to effectively separate the superposition of cooperative signals. Then, each timing-offset and each channel parameter are estimated in the separated signal. The proposed scheme effectively recovers the original data based on the timing-offset estimates and the channel estimates. The simulation results reveal the excellent performance of the suggested method in terms of MSE and PER.

  • Automated Creation of Beamformer-Based Optimum DOA Estimation Algorithm Using Genetic Algorithm

    Shunsuke YOSHIMURA  Hiroshi HIRAYAMA  Nobuyoshi KIKUMA  Kunio SAKAKIBARA  

     
    LETTER-Antennas and Propagation

      Vol:
    E95-B No:10
      Page(s):
    3332-3336

    A novel method for automatically creating an optimum direction-of-arrival (DOA) estimation algorithm for a given radio environment using a genetic algorithm (GA) is proposed. DOA estimation algorithms are generally described by parameters and operators. The performance of a DOA estimation algorithm is evaluated using root mean square error (RMSE) through computer simulations. A GA searches for the combination of parameters and operators that gives the lowest RMSE. Because a GA can treat only bit strings, Polish notation is used to convert bit strings into a DOA estimation algorithm. A computer simulation showed that the proposed method can create a new angle spectrum function. The created angle spectrum function has higher resolution than the Capon method.

  • Spatial Variance of Bistatic SAR with One Fixed Station

    Junjie WU  Jianyu YANG  Yulin HUANG  Haiguang YANG  Lingjiang KONG  

     
    PAPER-Sensing

      Vol:
    E95-B No:10
      Page(s):
    3270-3278

    Bistatic synthetic aperture radar (BSAR) with one fixed station (OF-BSAR) can be used in wide area surveillance, ground moving target indication etc. This paper analyzes the spatial variance of OF-BSAR. Analytical expressions of the spatial invariance region in the data space are given. Using these results, we can determine the spatial invariance region in the data set and the imaging area. After that, we give a data blocking scheme for raw data focusing. Numerical simulation verifies the results of this paper.

  • A Miniaturized 2.5 GHz 8 W GaN HEMT Power Amplifier Module Using Selectively Anodized Aluminum Oxide Substrate

    Hae-Chang JEONG  Kyung-Whan YEOM  

     
    PAPER

      Vol:
    E95-C No:10
      Page(s):
    1580-1588

    In this paper, the design and fabrication of a miniaturized class-F 2.5 GHz 8 W power amplifier using a commercially available GaN HEMT bare chip from TriQuint and a Selectively Anodized Aluminum Oxide (SAAO) substrate are presented. The SAAO process was recently proposed and patented by Wavenics Inc., Daejeon, Korea, which provides the fabrication of small size circuit comparable to conventional MMIC and at drastically low cost due to the use of aluminum as a wafer. The advantage of low cost is especially promising for RF components fabrication in commercial applications like mobile communications. The fabricated power amplifier has a compact size of 4.4 4.4 mm2 and shows power added efficiency (PAE) of about 35% and harmonic suppression of above 30 dBc for second and third harmonics at an output power of 39 dBm.

  • Conjugate-Gradient Based Doubly Selective Channel Estimation and Equalization for OFDM Systems

    Dongjae LEE  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Vol:
    E95-B No:10
      Page(s):
    3252-3260

    This paper addresses conjugate-gradient (CG) based pilot-assisted channel estimation and equalization in doubly selective channels for orthogonal frequency division multiplexing (OFDM) block transmissions. With the help of the discrete prolate spheroidal sequence, which shows flat mean-square error (MSE) curves for the reconstructed channels in the presence of Doppler frequency mismatch, a basis expansion model for a parsimonious channel representation over multiple OFDM blocks is developed, a system equation for the least square channel estimation under widely used pilot lattices, where the pilot symbols are irregularly placed in the subcarrier domain, is formulated by introducing carving matrices, and the standard CG method is applied to the system. Relying on the CG method again, the linear minimum mean-square error channel equalization is pursued without performing any matrix inversion, while elevating the convergence speed of the iterative algorithm with a simple preconditioner. Finally, we validate our schemes with numerical experiments on the integrated services digital broadcasting-terrestrial system in doubly-selective channels and determine the normalized MSE and uncoded bit error rate.

  • Miniaturized Antenna with High Radiation Efficiency Using Ground and Chip Capacitors

    Hyengcheul CHOI  Kyung-Young JUNG  Hyeongdong KIM  

     
    LETTER-Antennas and Propagation

      Vol:
    E95-B No:10
      Page(s):
    3328-3331

    Ground antennas are suitable for use in mobile electronic devices due to their compactness. These ground antennas incorporate two capacitors for controlling the resonance frequency and a shorting loop for impedance matching. In this work, we compare the performance of a ground antenna with that of a meandered inverted-F antenna (IFA). It is numerically and experimentally shown that a ground antenna can yield simultaneous improvements in both the antenna size and radiation efficiency when compared to the meandered IFA. The bandwidth of the ground antenna for a voltage standing wave ratio (VSWR) of 3:1 is 240 MHz from 2350 MHz to 2590 MHz, while the minimum total antenna efficiency is 62% within the 2.4 GHz ISM band.

  • A 60 GHz CMOS Transceiver IC for a Short-Range Wireless System with Amplitude/Phase Imbalance Cancellation Technique

    Koji TAKINAMI  Junji SATO  Takahiro SHIMA  Mitsuhiro IWAMOTO  Taiji AKIZUKI  Masashi KOBAYASHI  Masaki KANEMARU  Yohei MORISHITA  Ryo KITAMURA  Takayuki TSUKIZAWA  Koichi MIZUNO  Noriaki SAITO  Kazuaki TAKAHASHI  

     
    PAPER

      Vol:
    E95-C No:10
      Page(s):
    1598-1609

    A 60 GHz direct conversion transceiver which employs amplitude/phase imbalance cancellation technique is newly proposed. By using the proposed technique, the receive path of the transceiver achieves less than 0.2 dB of amplitude error and less than 3 of phase error at 60 GHz bands over a 10 GHz bandwidth, which relaxes the design accuracy required for baluns used in the transceiver. It also employs a simple and fast calibration algorithm to adjust the locking range of the divide-by-3 injection locked divider in the phase locked loop. Fabricated in 90 nm CMOS technology, the transceiver achieves a low power consumption of 230 mW in transmit mode and 173 mW in receive mode. The output spectrum of 1.76 Gsps π/2-BPSK/QPSK modulation shows the excellent distortion and spurious suppression that meet the IEEE802.11ad draft standard.

  • A New Method for Constructing Asymmetric ZCZ Sequence Sets

    Hideyuki TORII  Takahiro MATSUMOTO  Makoto NAKAMURA  

     
    PAPER-Spread Spectrum Technologies and Applications

      Vol:
    E95-A No:9
      Page(s):
    1577-1586

    The present paper proposes a new method for constructing polyphase asymmetric zero-correlation zone (A-ZCZ) sequence sets. The proposed method can generate A-ZCZ sequence sets that cannot be obtained from methods proposed by other researchers and is a generalized version of our previously proposed method. An A-ZCZ sequence set can be regarded as a ZCZ sequence set. The newly obtained A-ZCZ sequence sets include quasi-optimal ZCZ sequence sets of which the zero-cross-correlation zone (ZCCZ) length between different sequence subsets is larger than the mathematical upper bound of conventional ZCZ sequence sets. A new method for extending the A-ZCZ sequence sets is also presented in the present paper.

  • Optimal Control of Probabilistic Boolean Networks Using Polynomial Optimization

    Koichi KOBAYASHI  Kunihiko HIRAISHI  

     
    PAPER-Systems and Control

      Vol:
    E95-A No:9
      Page(s):
    1512-1517

    In this paper, the optimal control problem of a probabilistic Boolean network (PBN), which is one of the significant models in gene regulatory networks, is discussed. In the existing methods of optimal control for PBNs, it is necessary to compute state transition diagrams with 2n nodes for a given PBN with n states. To avoid this computation, a polynomial optimization approach is proposed. In the proposed method, a PBN is transformed into a polynomial system, and the optimal control problem is reduced to a polynomial optimization problem. Since state transition diagrams are not computed, the proposed method is convenient for users.

  • Floorplanning for High Utilization of Heterogeneous FPGAs

    Nan LIU  Song CHEN  Takeshi YOSHIMURA  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E95-A No:9
      Page(s):
    1529-1537

    Heterogeneous resources such as configurable logic blocks (CLBs), multiplier blocks (MULs) and RAM blocks (RAMs) where millions of logic gates are included have been added to field programmable gate arrays (FPGAs). The fixed-outline floorplanning used by the existing methods always has a big penalty item in the objective function to ensure all the modules are placed in the specified chip region, which maybe greatly degrade the wirelength. This paper presents a three-phase floorplanning method for heterogeneous FPGAs. First, a non-slicing free-outline floorplanning method is used to optimize the wirelength, however, in this phase, the satisfaction of resource requirements from functional modules might fail. Second, a min-cost-max-flow algorithm is used to tune the assignment of CLBs to functional modules, and assign contiguous regions to each module so that all the functional modules satisfy CLB requirements. Finally, the MULs and RAMs are allocated to modules by a network flow model. CLBs hold the maximum quantity among all the resources. Therefore, making a high utilization of them means an enhancement of the FPGA densities. The proposed method can improve the utilization of CLBs, hence, much larger circuits could be mapped to the same FPGA chip. The results show that about 7–85% wirelength reduction is obtained, and CLB utilization is improved by about 25%.

  • Robust Generalized-Sidelobe-Cancellation-Based Receivers for MC-CDMA Uplink against Carrier Frequency Offsets

    Tsui-Tsai LIN  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E95-B No:9
      Page(s):
    3011-3014

    This letter presents a robust receiver using the generalized sidelobe canceller aided with the high-order derivative constraint technique for multicarrier code-division multiple-access (MC-CDMA) uplink against carrier frequency offset (CFO). Numerical results demonstrate the efficacy of the proposed receiver.

  • Inclined Slot Array Antennas on a Hollow Rectangular Coaxial Line

    Satoshi YAMAGUCHI  Yukihiro TAHARA  Toru TAKAHASHI  Kazushi NISHIZAWA  Hiroaki MIYASHITA  Yoshihiko KONISHI  

     
    PAPER-Antennas and Propagation

      Vol:
    E95-B No:9
      Page(s):
    2870-2877

    Slotted-waveguide array antennas are attractive because of their low-loss characteristics at high frequencies. Several types of slotted arrays whose polarization angles are inclined to the waveguide axis have been reported. In this paper, we propose a new type of slot array antenna on a rectangular coaxial line for minimizing the waveguide width. As opposed to a conventional waveguide, there is no “cut-off” concept in our proposal because the coaxial line is a transverse electromagnetic (TEM) line. Therefore it is possible to guide the wave even if the diameter of the line is much smaller than that of the waveguide. Moreover, the proposed antenna is a resonant slot array antenna that is based on standing-wave excitation and is thus different from traveling-wave antennas (such as a leaky coaxial cable (LCX)).

  • Effective Fault Localization Approach Using Feedback

    Yan LEI  Xiaoguang MAO  Ziying DAI  Dengping WEI  

     
    PAPER-Software Engineering

      Vol:
    E95-D No:9
      Page(s):
    2247-2257

    At the stage of software debugging, the effective interaction between software debugging engineers and fault localization techniques can greatly improve fault localization performance. However, most fault localization approaches usually ignore this interaction and merely utilize the information from testing. Due to different goals of testing and fault localization, the lack of interaction may lead to the issue of information inadequacy, which can substantially degrade fault localization performance. In addition, human work is costly and error-prone. It is vital to study and simulate the pattern of debugging engineers as they apply their knowledge and experience to this interaction to promote fault localization effectiveness and reduce their workload. Thus this paper proposes an effective fault localization approach to simulate this interaction via feedback. Based on results obtained from fault localization techniques, this approach utilizes test data generation techniques to automatically produce feedback for interacting with these fault localization techniques, and then iterate this process to improve fault localization performance until a specific stopping condition is satisfied. Experiments on two standard benchmarks demonstrate the significant improvement of our approach over a promising fault localization technique, namely the spectrum-based fault localization technique.

  • Synchronization Based Redundant Routing for Multihop Networks

    Wonjong NOH  Jihoon LEE  Sangkyung KIM  

     
    LETTER-Network

      Vol:
    E95-B No:9
      Page(s):
    2952-2955

    This paper proposes a new on-demand routing protocol. It aims to establish a redundant route path containing intermediate nodes having relatively more synchronized neighbor nodes in a possible route. This approach can localize the effects of route failures and reduce route reconfiguration time by enhancing the reachability to the destination node without source-initiated route re-discoveries at route failures. Simulation results show that it has better performance than AODV and TORA.

  • Crosstalk Analysis and Measurement Technique for High Frequency Signal Transfer in MEMs Probe Pins

    Duc Long LUONG  Hyeonju BAE  Wansoo NAH  

     
    PAPER

      Vol:
    E95-C No:9
      Page(s):
    1459-1464

    This paper develops a methodology of crosstalk analysis/measurement techniques for the design and fabrication of the MEMs (Micro-ElectroMichanical system) probe card. By introducing more ground pins into the connector pins, the crosstalk characteristics can be enhanced and a design guide for the parameters, such as pin's size and pitch is proposed to satisfy the given crosstalk limitation of -30 dB for reliable high speed signal transfer. The paper also presents a novel method to characterize scattering parameters of multiport interconnect circuits with a 4-port VNA (Vector Network Analyzer). By employing the re-normalization of scattering matrices with different reference impedances at other ports, data obtained from 4-port configuration measurements can be synthesized to build a full scattering matrix of the DUT (Device-Under-Test, MEMs probe connector pins). In comparison to the conventional 2-port VNA re-normalization method, proposed technique has two advantages: saving of measuring time, and enhanced accuracy even with open-ended unmeasured ports. A good agreement of the estimated and correct S parameters verifies the validness of the proposed algorithm.

  • Application of Markov Chain Monte Carlo Random Testing to Test Case Prioritization in Regression Testing

    Bo ZHOU  Hiroyuki OKAMURA  Tadashi DOHI  

     
    PAPER

      Vol:
    E95-D No:9
      Page(s):
    2219-2226

    This paper proposes the test case prioritization in regression testing. The large size of a test suite to be executed in regression testing often causes large amount of testing cost. It is important to reduce the size of test cases according to prioritized test sequence. In this paper, we apply the Markov chain Monte Carlo random testing (MCMC-RT) scheme, which is a promising approach to effectively generate test cases in the framework of random testing. To apply MCMC-RT to the test case prioritization, we consider the coverage-based distance and develop the algorithm of the MCMC-RT test case prioritization using the coverage-based distance. Furthermore, the MCMC-RT test case prioritization technique is consistently comparable to coverage-based adaptive random testing (ART) prioritization techniques and involves much less time cost.

  • Facial Expression Recognition via Sparse Representation

    Ruicong ZHI  Qiuqi RUAN  Zhifei WANG  

     
    LETTER-Pattern Recognition

      Vol:
    E95-D No:9
      Page(s):
    2347-2350

    A facial components based facial expression recognition algorithm with sparse representation classifier is proposed. Sparse representation classifier is based on sparse representation and computed by L1-norm minimization problem on facial components. The features of “important” training samples are selected to represent test sample. Furthermore, fuzzy integral is utilized to fuse individual classifiers for facial components. Experiments for frontal views and partially occluded facial images show that this method is efficient and robust to partial occlusion on facial images.

  • CompSize: A Model-Based and Automated Approach to Size Estimation of Embedded Software Components

    Kenneth LIND  Rogardt HELDAL  

     
    PAPER

      Vol:
    E95-D No:9
      Page(s):
    2183-2192

    Accurate estimation of Software Code Size is important for developing cost-efficient embedded systems. The Code Size affects the amount of system resources needed, like ROM and RAM memory, and processing capacity. In our previous work, we have estimated the Code Size based on CFP (COSMIC Function Points) within 15% accuracy, with the purpose of deciding how much ROM memory to fit into products with high cost pressure. Our manual CFP measurement process would require 2.5 man years to estimate the ROM size required in a typical car. In this paper, we want to investigate how the manual effort involved in estimation of Code Size can be minimized. We define a UML Profile capturing all information needed for estimation of Code Size, and develop a tool for automated estimation of Code Size based on CFP. A case study will show how UML models save manual effort in a realistic case.

2041-2060hit(5900hit)