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3181-3200hit(16314hit)

  • A Partitioning Parallelization with Hybrid Migration of MOEA/D for Bi-Objective Optimization on Message-Passing Clusters

    Yu WU  Yuehong XIE  Weiqin YING  Xing XU  Zixing LIU  

     
    LETTER-Numerical Analysis and Optimization

      Vol:
    E99-A No:4
      Page(s):
    843-848

    A partitioning parallelization of the multi-objective evolutionary algorithm based on decomposition, pMOEA/D, is proposed in this letter to achieve significant time reductions for expensive bi-objective optimization problems (BOPs) on message-passing clusters. Each sub-population of pMOEA/D resides on a separate processor in a cluster and consists of a non-overlapping partition and some extra overlapping individuals for updating neighbors. Additionally, sub-populations cooperate across separate processors by the hybrid migration of elitist individuals and utopian points. Experimental results on two benchmark BOPs and the wireless sensor network layout problem indicate that pMOEA/D achieves satisfactory performance in terms of speedup and quality of solutions on message-passing clusters.

  • A New Scheme of Blockcipher Hash

    Rashed MAZUMDER  Atsuko MIYAJI  

     
    PAPER-Cryptography and cryptographic protocols

      Pubricized:
    2016/01/13
      Vol:
    E99-D No:4
      Page(s):
    796-804

    A cryptographic hash is an important tool in the area of a modern cryptography. It comprises a compression function, where the compression function can be built by a scratch or blockcipher. There are some familiar schemes of blockcipher compression function such as Weimar, Hirose, Tandem, Abreast, Nandi, ISA-09. Interestingly, the security proof of all the mentioned schemes are based on the ideal cipher model (ICM), which depends on ideal environment. Therefore, it is desired to use such a proof technique model, which is close to the real world such as weak cipher model (WCM). Hence, we proposed an (n, 2n) blockcipher compression function, which is secure under the ideal cipher model, weak cipher model and extended weak cipher model (ext.WCM). Additionally, the majority of the existing schemes need multiple key schedules, where the proposed scheme and the Hirose-DM follow single key scheduling property. The efficiency-rate of our scheme is r=1/2. Moreover, the number of blockcipher call of this scheme is 2 and it runs in parallel.

  • Node-to-Set Disjoint Paths Problem in a Möbius Cube

    David KOCIK  Yuki HIRAI  Keiichi KANEKO  

     
    PAPER-Dependable Computing

      Pubricized:
    2015/12/14
      Vol:
    E99-D No:3
      Page(s):
    708-713

    This paper proposes an algorithm that solves the node-to-set disjoint paths problem in an n-Möbius cube in polynomial-order time of n. It also gives a proof of correctness of the algorithm as well as estimating the time complexity, O(n4), and the maximum path length, 2n-1. A computer experiment is conducted for n=1,2,...,31 to measure the average performance of the algorithm. The results show that the average time complexity is gradually approaching to O(n3) and that the maximum path lengths cannot be attained easily over the range of n in the experiment.

  • An InP-Based 27-GHz-Bandwidth Limiting TIA IC Designed to Suppress Undershoot and Ringing in Its Output Waveform

    Hiroyuki FUKUYAMA  Michihiro HIRATA  Kenji KURISHIMA  Minoru IDA  Masami TOKUMITSU  Shogo YAMANAKA  Munehiko NAGATANI  Toshihiro ITOH  Kimikazu SANO  Hideyuki NOSAKA  Koichi MURATA  

     
    PAPER-Electronic Circuits

      Vol:
    E99-C No:3
      Page(s):
    385-396

    A design scheme for a high-speed differential-input limiting transimpedance amplifier (TIA) was developed. The output-stage amplifier of the TIA is investigated in detail in order to suppress undershoot and ringing in the output waveform. The amplifier also includes a peak detector for the received signal strength indicator (RSSI) output, which is used to control the optical demodulator for differential-phase-shift-keying or differential-quadrature-phase-shift-keying formats. The limiting TIA was fabricated on the basis of 1-µm emitter-width InP-based heterojunction-bipolar-transistor (HBT) IC technology. Its differential gain is 39 dB, its 3-dB bandwidth is 27 GHz, and its estimated differential transimpedance gain is 73 dBΩ. The obtained output waveform shows that the developed design scheme is effective for suppressing undershoot and ringing.

  • Contribution of Treatment Temperature on Quantum Efficiency of Negative Electron Affinity (NEA)-GaAs

    Yuta INAGAKI  Kazuya HAYASE  Ryosuke CHIBA  Hokuto IIJIMA  Takashi MEGURO  

     
    PAPER

      Vol:
    E99-C No:3
      Page(s):
    371-375

    Quantum efficiency (QE) evolution by several negative electron affinity (NEA) activation process for p-doped GaAs(100) specimen has been studied. We have carried out the surface pretreatment at 580°C or 480°C and the successive NEA activation process at room temperature (R.T.). When the NEA surface was degraded, the surface was refreshed by above pretreatment and activation process, and approximately 0.10 of QE was repeatedly obtained. It was found that the higher QE of 0.13 was achieved with the reduced pretreatment temperature at 480°C with the specific experimental conditions. This is probably caused by the residual Cs-related compounds playing an important role of the electron emission. In addition, after the multiple pretreatment and activation sequence, surface morphology of GaAs remarkably changed.

  • Optical Filters Based on Nano-Sized Hole and Slit Patterns in Aluminum Films

    Daisuke INOUE  Atsushi MIURA  Tsuyoshi NOMURA  Hisayoshi FUJIKAWA  Kazuo SATO  Naoki IKEDA  Daiju TSUYA  Yoshimasa SUGIMOTO  Yasuo KOIDE  

     
    PAPER

      Vol:
    E99-C No:3
      Page(s):
    358-364

    The optical properties of arrays of nanoholes and nanoslits in Al films were investigated both numerically and experimentally. The choice of Al was based on its low cost and ease of processing, in addition to the fact that it has a higher plasma frequency than gold or silver, leading to lower optical losses at wavelengths of 400 to 500nm.

  • Wheeze Detection Algorithm Based on Correlation-Coefficients Analysis

    Jiarui LI  Ying HONG  Chengpeng HAO  

     
    LETTER-Digital Signal Processing

      Vol:
    E99-A No:3
      Page(s):
    760-764

    Wheeze is a general sign for obstructive airway diseases whose clinical diagnosis mainly depends on auscultating or X-ray imaging with subjectivity or harm. Therefore, this paper introduces an automatic, noninvasive method to detect wheeze which consists of STFT decomposition, preprocessing of the spectrogram, correlation-coefficients calculating and duration determining. In particular, duration determining takes the Haas effect into account, which facilitates us to achieve a better determination. Simulation result shows that the sensibility (SE), the specificity (SP) and the accuracy (AC) are 88.57%, 97.78% and 93.75%, respectively, which indicates that this method could be an efficient way to detect wheeze.

  • STM Study on Adsorption Structures of Cs on the As-Terminated GaAs(001) (2×4) Surface by Alternating Supply of Cs and O2

    Masayuki HIRAO  Daichi YAMANAKA  Takanori YAZAKI  Jun OSAKO  Hokuto IIJIMA  Takao SHIOKAWA  Hikota AKIMOTO  Takashi MEGURO  

     
    PAPER

      Vol:
    E99-C No:3
      Page(s):
    376-380

    Negative electron affinity (NEA) surfaces can be formed by alternating supply of alkali metals (e.g. Cs, Rb, K) and oxygen on semiconductor surfaces. We have studied adsorption structures of Cs on an As-terminated (2×4) (001) GaAs surface using scanning tunneling microscopy (STM). We found that the initial adsorption of Cs atoms occurs around the step sites in the form of Cs clusters and that the size of clusters is reduced by successive exposure to O2, indicating that As-terminated (2×4) surfaces are relatively stable compared to Ga-terminated surfaces and are not broken by the Cs clusters adsorption.

  • Real Cholesky Factor-ADI Method for Low-Rank Solution of Projected Generalized Lyapunov Equations

    Yuichi TANJI  

     
    PAPER-Nonlinear Problems

      Vol:
    E99-A No:3
      Page(s):
    702-709

    The alternating direction implicit (ADI) method is proposed for low-rank solution of projected generalized continuous-time algebraic Lyapunov equations. The low-rank solution is expressed by Cholesky factor that is similar to that of Cholesky factorization for linear system of equations. The Cholesky factor is represented in a real form so that it is useful for balanced truncation of sparsely connected RLC networks. Moreover, we show how to determine the shift parameters which are required for the ADI iterations, where Krylov subspace method is used for finding the shift parameters that reduce the residual error quickly. In the illustrative examples, we confirm that the real Cholesky factor certainly provides low-rank solution of projected generalized continuous-time algebraic Lyapunov equations. Effectiveness of the shift parameters determined by Krylov subspace method is also demonstrated.

  • Characteristic Analysis and Tolerance Analysis of Nonlinear Resistive Circuits Using Integer Programming

    Kiyotaka YAMAMURA  Suguru ISHIGURO  Hiroshi TAKI  

     
    PAPER-Nonlinear Problems

      Vol:
    E99-A No:3
      Page(s):
    710-719

    This paper presents efficient and easily implementable methods for the characteristic analysis and tolerance analysis of nonlinear resistive circuits using integer programming. In these methods, the problem of finding all characteristic curves or all solution sets (regions of possible operating points) is formulated as a mixed integer programming problem, and it is solved by a high-performance integer programming solver such as CPLEX. It is shown that the proposed methods can easily be implemented without making complicated programs, and that all characteristic curves or all solution sets are obtained by solving mixed integer programming problems several times. Numerical examples are given to confirm the effectiveness of the proposed methods.

  • Decoding of Projective Reed-Muller Codes by Dividing a Projective Space into Affine Spaces

    Norihiro NAKASHIMA  Hajime MATSUI  

     
    PAPER-Coding Theory

      Vol:
    E99-A No:3
      Page(s):
    733-741

    A projective Reed-Muller (PRM) code, obtained by modifying a Reed-Muller code with respect to a projective space, is a doubly extended Reed-Solomon code when the dimension of the related projective space is equal to 1. The minimum distance and the dual code of a PRM code are known, and some decoding examples have been presented for low-dimensional projective spaces. In this study, we construct a decoding algorithm for all PRM codes by dividing a projective space into a union of affine spaces. In addition, we determine the computational complexity and the number of correctable errors of our algorithm. Finally, we compare the codeword error rate of our algorithm with that of the minimum distance decoding.

  • Human Motion Classification Using Radio Signal Strength in WBAN

    Sukhumarn ARCHASANTISUK  Takahiro AOYAGI  Tero UUSITUPA  Minseok KIM  Jun-ichi TAKADA  

     
    PAPER

      Vol:
    E99-B No:3
      Page(s):
    592-601

    In this paper, a novel approach of a human motion classification system in wireless body area network (WBAN) using received radio signal strength was developed. This method enables us to classify human motions in WBAN using only the radio signal strength during communication without additional tools such as an accelerometer. The proposed human motion classification system has a potential to be used for improving communication quality in WBAN as well as recording daily-life activities for self-awareness tool. To construct the classification system, a numerical simulation was used to generate WBAN propagation channel in various motions at frequency band of 403.5MHz and 2.45GHz. In the classification system, a feature vector representing a characteristic of human motions was computed from time-series received signal levels. The proposed human motion classification using the radio signal strength based on WBAN simulation can classify 3-5 human motions with the accuracy rate of 63.8-95.7 percent, and it can classify the human motions regardless of frequency band. In order to confirm that the human motion classification using radio signal strength can be used in practice, the applicability of the classification system was evaluated by WBAN measurement data.

  • Connector Model for Use in Common-Mode Antenna Model Used to Estimate Radiation from Printed Circuit Boards with Board-to-Board Connector

    Yuri WAKADUKI  Tetsushi WATANABE  Yoshitaka TOYOTA  Kengo IOKIBE  Liuji R. KOGA  Osami WADA  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E99-B No:3
      Page(s):
    695-702

    A connector model expressed as an inductance is proposed for use in a previously reported common-mode antenna model. The common-mode antenna model is an equivalent model for estimating only common-mode radiation from a printed circuit board (PCB) more quickly and with less computational resources than a calculation method that fully divides the entire structure of the PCB into elemental cells, such as narrow signal traces and thin dielectric layers. Although the common-mode antenna model can estimate the amount of radiation on the basis of the pin configuration of the connector between two PCBs, the calculation results do not show the peak frequency shift in the radiation spectrum when there is a change in the pin configuration. A previous study suggested that the frequency shift depends on the total inductance of the connector, which led to the development of the connector model reported here, which takes into account the effective inductance of the connector. The common-mode antenna model with the developed connector model accurately simulates the peak frequency shift caused by a change in the connector pin configuration. The results agree well with measured spectra (error of 3 dB).

  • An Efficient Selection Method of a Transmitted OFDM Signal Sequence for Various SLM Schemes

    Kee-Hoon KIM  Hyun-Seung JOO  Jong-Seon NO  Dong-Joon SHIN  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:3
      Page(s):
    703-713

    Many selected mapping (SLM) schemes have been proposed to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signal sequences. In this paper, an efficient selection (ES) method of the OFDM signal sequence with minimum PAPR among many alternative OFDM signal sequences is proposed; it supports various SLM schemes. Utilizing the fact that OFDM signal components can be sequentially generated in many SLM schemes, the generation and PAPR observation of the OFDM signal sequence are processed concurrently. While the u-th alternative OFDM signal components are being generated, by applying the proposed ES method, the generation of that alternative OFDM signal components can be interrupted (or stopped) according to the selection criteria of the best OFDM signal sequence in the considered SLM scheme. Such interruption substantially reduces the average computational complexity of SLM schemes without degradation of PAPR reduction performance, which is confirmed by analytical and numerical results. Note that the proposed method is not an isolated SLM scheme but a subsidiary method which can be easily adopted in many SLM schemes in order to further reduce the computational complexity of considered SLM schemes.

  • OSIC Scheme Based on Combined Post-Processing SINR for MIMO Systems with Retransmission

    Sangjoon PARK  Sooyong CHOI  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:3
      Page(s):
    732-738

    An ordered successive interference cancellation (OSIC) scheme based on combined post-processing signal-to-interference-plus-noise ratio (PSINR) is proposed for multiple-input multiple-output (MIMO) systems with retransmission. For the OSIC procedures at the current transmission round, instead of reusing the PSINRs and decision statistics calculated for the previous transmission rounds, the proposed OSIC scheme newly calculates the combined PSINRs and combined decision statistics from the available receive signal vectors and channel matrices at every retransmission. Therefore, the proposed OSIC scheme utilizes all receive signal vectors and channel matrices obtained up to the current transmission round during the OSIC procedures. A low-complexity version of the proposed OSIC scheme is also proposed, and the low-complexity version recalculates the combined PSINRs and combined decision statistics from part of the available receive signal vectors and channel matrices. Simulation results verify that the proposed schemes achieve significantly better error performance than existing OSIC schemes based on the detection and combining process for MIMO systems with retransmission.

  • A Moving Source Localization Method Using TDOA, FDOA and Doppler Rate Measurements

    Dexiu HU  Zhen HUANG  Xi CHEN  Jianhua LU  

     
    PAPER-Sensing

      Vol:
    E99-B No:3
      Page(s):
    758-766

    This paper proposes a moving source localization method that combines TDOA, FDOA and doppler rate measurements. First, the observation equations are linearized by introducing nuisance variables and an initial solution of all the variables is acquired using the weighted least squares method. Then, the Taylor expression and gradient method is applied to eliminate the correlation between the elements in the initial solution and obtain the final estimation of the source position and velocity. The proposed method achieves CRLB derived using TDOA, FDOA and doppler rate and is much more accurate than the conventional TDOA/FDOA based method. In addition, it can avoid the rank-deficiency problem and is more robust than the conventional method. Simulations are conducted to examine the algorithm's performance and compare it with conventional TDOA/FDOA based method.

  • An Area-Efficient Scalable Test Module to Support Low Pin-Count Testing

    Tong-Yu HSIEH  Tai-Ping WANG  Shuo YANG  Chin-An HSU  Yi-Lung LIN  

     
    PAPER-Electronic Circuits

      Vol:
    E99-C No:3
      Page(s):
    404-414

    Low pin-count testing is an effective method to reduce test cost. Based on this method multi-site testing, i.e., where multiple devices are tested concurrently, can be supported under the limitation on the number of channels provided by ATE. In this work we propose a scalable test module (called STM) design that can support multi-site testing more efficiently when compared with previous work. In the previous work, the total number of devices that can be tested concurrently is usually fixed when the design for testability hardware is designed. For our STM, each STM can deal with a number of circuits to be tested at the same time. Moreover, STM is scalable, i.e., multiple STMs can work collaboratively while the ATE bandwidth still remains the same to further increase the degree of test parallelism. Our STM will be integrated with ATE and serve as an interface between ATE and circuits under test (CUT). Only four pins are required by STM to communicate with ATE, and IEEE 1149.1 Std. ports are employed to transfer test data to/from CUTs. STM has been verified via silicon proof, which contains only about 2,768 logic gates. Experiments results for a number of ISCAS and IWLS'05 benchmark circuits also demonstrate that by making good use of the scalable feature of STM, test efficiency can be enhanced significantly.

  • Real-Time Vital Monitoring for Persons during Exercises — Solutions and Challenges — Open Access

    Shinsuke HARA  Hiroyuki OKUHATA  Takashi KAWABATA  Hajime NAKAMURA  Hiroyuki YOMO  

     
    INVITED PAPER

      Vol:
    E99-B No:3
      Page(s):
    556-564

    In the field of education such as elementary and middle schools, teachers want to take care of schoolchildren during physical trainings and after-school club activities. On the other hand, in the field of sports such as professional and national-level sports, physical or technical trainers want to manage the health, physical and physiological conditions of athletes during exercise trainings in the grounds. In this way, it is required to monitor vital signs for persons during exercises, however, there are several technical problems to be solved in its realization. In this paper, we present the importance and necessity of vital monitoring for persons during exercises, and to make it possible periodically, reliably and in real-time, we present the solutions which we have so far worked out and point out remaining technical challenges in terms of vital/physical sensing, wireless transmission and human interface.

  • Slicing Fine-Grained Code Change History

    Katsuhisa MARUYAMA  Takayuki OMORI  Shinpei HAYASHI  

     
    PAPER-Software Engineering

      Pubricized:
    2015/12/21
      Vol:
    E99-D No:3
      Page(s):
    671-687

    Change-aware development environments can automatically record fine-grained code changes on a program and allow programmers to replay the recorded changes in chronological order. However, since they do not always need to replay all the code changes to investigate how a particular entity of the program has been changed, they often eliminate several code changes of no interest by manually skipping them in replaying. This skipping action is an obstacle that makes many programmers hesitate when they use existing replaying tools. This paper proposes a slicing mechanism that automatically removes manually skipped code changes from the whole history of past code changes and extracts only those necessary to build a particular class member of a Java program. In this mechanism, fine-grained code changes are represented by edit operations recorded on the source code of a program and dependencies among edit operations are formalized. The paper also presents a running tool that slices the operation history and replays its resulting slices. With this tool, programmers can avoid replaying nonessential edit operations for the construction of class members that they want to understand. Experimental results show that the tool offered improvements over conventional replaying tools with respect to the reduction of the number of edit operations needed to be examined and over history filtering tools with respect to the accuracy of edit operations to be replayed.

  • Nonlinear-Error-Free Optical Quantization Using Dense Spectral Slicing

    Takahiro KODAMA  Ryosuke MATSUMOTO  Akihiro MARUTA  Tsuyoshi KONISHI  Ken-ichi KITAYAMA  

     
    PAPER-Fiber-Optic Transmission for Communications

      Vol:
    E99-B No:3
      Page(s):
    647-653

    We numerically and experimentally demonstrate for the first time a novel all-optical quantization technique using dense spectral slicing with a specially designed arrayed waveguide grating for orthogonal frequency division multiplexed signals. By using a mode-locked laser diode with low jitter, the quantization technique can be achieved a high-speed and low-jitter operation. Both numerical and experimental results confirm the feasibility of 10 GSample/s, completely linear 3-bit step quantization for photonic analog to digital conversion. This optical quantization technique will be beneficial for ultra-high-speed optical communication using digital signal processing.

3181-3200hit(16314hit)