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[Keyword] PAR(2741hit)

1121-1140hit(2741hit)

  • Automation Power Energy Management Strategy for Mobile Telecom Industry

    Jong-Ching HWANG  Jung-Chin CHEN  Jeng-Shyang PAN  Yi-Chao HUANG  

     
    PAPER

      Vol:
    E93-B No:9
      Page(s):
    2232-2238

    The aim of this research is to study the power energy cost reduction of the mobile telecom industry through the supervisor control and data acquisition (SCADA) system application during globalization and liberalization competition. Yet this management system can be proposed functions: operating monitors, the analysis on load characteristics and dropping the cost of management.

  • Intra-Cell Partial Spectrum Reuse Scheme for Cellular OFDM-Relay Networks

    Tong WU  Ying WANG  Yushan PEI  Gen LI  Ping ZHANG  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E93-B No:9
      Page(s):
    2462-2464

    This letter proposes an intra-cell partial spectrum reuse (PSR) scheme for cellular OFDM-relay networks. The proposed method aims to increase the system throughput, while the SINR of the cell edge users can be also promoted by utilizing the PSR scheme. The novel pre-allocation factor γ not only indicates the flexibility of PSR, but also decreases the complexity of the reuse mechanism. Through simulations, the proposed scheme is shown to offer superior performances in terms of system throughput and SINR of last 5% users.

  • M-Channel Paraunitary Filter Banks Based on Direct Lifting Structure of Building Block and Its Inverse Transform for Lossless-to-Lossy Image Coding

    Taizo SUZUKI  Masaaki IKEHARA  

     
    PAPER-Digital Signal Processing

      Vol:
    E93-A No:8
      Page(s):
    1457-1464

    This paper presents a paraunitary filter bank (PUFB) based on a direct lifting structure of a building block and its inverse transform for lossless-to-lossy image coding. Although the conventional lifting-based filter banks (LBFBs), which are constructed by lifting structures with integer coefficients and rounding operations, suffer from degradation of coding performance due to much rounding error generated by cascading lifting structures, our proposals can be applied to any PUFB without losing many ones because building blocks can be applied to every lifting block as it is. It is constructed with very simple structures and many rounding operations are eliminated. Additionally, the number of rounding operations is reduced more by using two-dimensional block transform (2DBT) of separated transform to each building block. As result, even though the proposed PUFBs require a little side information block (SIB), they show better coding performance in lossless-to-lossy image coding than the conventional ones.

  • A Low-Complexity Sparse Channel Estimation Method for OFDM Systems

    Bin SHENG  Pengcheng ZHU  Xiaohu YOU  Lan CHEN  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E93-B No:8
      Page(s):
    2211-2214

    In this letter, we propose a low-complexity sparse channel estimation method for orthogonal frequency division multiplexing (OFDM) systems. The proposed method uses a discrete Fourier transform (DFT)-based technique for channel estimation and a novel sorted noise space discrimination technique to estimate the channel length and tap positions. Simulation results demonstrate that the reduction in signal space improves the channel estimation performance.

  • Minimizing Human Intervention for Constructing Korean Part-of-Speech Tagged Corpus

    Do-Gil LEE  Gumwon HONG  Seok Kee LEE  Hae-Chang RIM  

     
    LETTER-Natural Language Processing

      Vol:
    E93-D No:8
      Page(s):
    2336-2338

    The construction of annotated corpora requires considerable manual effort. This paper presents a pragmatic method to minimize human intervention for the construction of Korean part-of-speech (POS) tagged corpus. Instead of focusing on improving the performance of conventional automatic POS taggers, we devise a discriminative POS tagger which can selectively produce either a single analysis or multiple analyses based on the tagging reliability. The proposed approach uses two decision rules to judge the tagging reliability. Experimental results show that the proposed approach can effectively control the quality of corpus and the amount of manual annotation by the threshold value of the rule.

  • Speech Emotion Recognition Based on Parametric Filter and Fractal Dimension

    Xia MAO  Lijiang CHEN  

     
    LETTER-Speech and Hearing

      Vol:
    E93-D No:8
      Page(s):
    2324-2326

    In this paper, we propose a new method that employs two novel features, correlation density (Cd) and fractal dimension (Fd), to recognize emotional states contained in speech. The former feature obtained by a list of parametric filters reflects the broad frequency components and the fine structure of lower frequency components, contributed by unvoiced phones and voiced phones, respectively; the latter feature indicates the non-linearity and self-similarity of a speech signal. Comparative experiments based on Hidden Markov Model and K Nearest Neighbor methods are carried out. The results show that Cd and Fd are much more closely related with emotional expression than the features commonly used.

  • Design of Hierarchical Fuzzy Classification System Based on Statistical Characteristics of Data

    Chang Sik SON  Yoon-Nyun KIM  Kyung-Ri PARK  Hee-Joon PARK  

     
    LETTER-Pattern Recognition

      Vol:
    E93-D No:8
      Page(s):
    2319-2323

    A scheme for designing a hierarchical fuzzy classification system with a different number of fuzzy partitions based on statistical characteristics of the data is proposed. To minimize the number of misclassified patterns in intermediate layers, a method of fuzzy partitioning from the defuzzified outputs of previous layers is also presented. The effectiveness of the proposed scheme is demonstrated by comparing the results from five datasets in the UCI Machine Learning Repository.

  • Verification of Spark-Resistance Formulae for Micro-Gap ESD

    Yoshinori TAKA  Osamu FUJIWARA  

     
    PAPER-ESD and Transients

      Vol:
    E93-B No:7
      Page(s):
    1801-1806

    Micro-gap electrostatic discharge (ESD) events due to a human with charge voltages below 1000 V cause serious malfunctions in high-tech information devices. For clarifying such a mechanism, it is indispensable to grasp the spark process of such micro-gap ESDs. For this purpose, two types of spark-resistance laws proposed by Rompe-Weizel and Toepler have often been used, which were derived from the hypotheses that spark conductivity be proportional to the internal energies and charges injected into a spark channel, respectively. However, their validity has not well been verified. To examine which spark-resistance formula could be applied for micro-gap ESDs, with a 12-GHz digital oscilloscope, we previously measured the discharge currents through the hand-held metal piece from a charged human with respect to charged voltages of 200 V and 2000 V, and thereby derived the conductance of a spark gap to reveal that both of their hypotheses are roughly valid in the initial stage of sparks. In this study, to further verify the above spark hypotheses, we derived the discharge voltages in closed forms across a spark gap based on the above spark-resistance formulae, and investigated which spark-resistance formula could be applied for micro-gap ESDs in comparison of spark gaps estimated from the measured discharge currents. As a result, we found that Rompe-Weizel's formula could well explain spark properties for micro-gap ESDs than Toepler's one regardless of charge voltages and approach speeds.

  • A Post-Wall Center-Feed Waveguide Circuit Consisting of T-Junctions for Reducing the Slot-Free Area in a Parallel Plate Slot Array Antenna

    Koh HASHIMOTO  Jiro HIROKAWA  Makoto ANDO  

     
    PAPER

      Vol:
    E93-C No:7
      Page(s):
    1047-1054

    A post-wall center-feed waveguide consisting of T-junctions is proposed for reducing the slot-free area of a parallel plate slot array antenna. The width of the slot-free area is reduced from 2.6 λ0 to 2.1 λ0. A sidelobe level in the E-plane is expected to be suppressed lower than that of the conventional center-feed antenna using cross-junctions. The method of moments with solid-wall replacement designs initially the T-junctions and HFSS including the post surfaces modifies only the reflection cancelling post. We have designed and fabricated a 61.25 GHz model antenna with uniform aperture illumination. The sidelobe level in the E-plane is suppressed to -9.5 dB while that of a conventional cross-junction type is -7.8 dB. Also, we suppress it to -13.8 dB by introducing a -8.3 dB amplitude tapered distribution in the array of the radiation slot pairs.

  • Design of Pseudo-Elliptical Wideband Bandpass Filter Using Stub Loaded Short-Circuited Parallel-Coupled Three-Line Units

    Chun-Ping CHEN  Junya TAKAHASHI  Zhewang MA  Tetsuo ANADA  Jui-Pang HSU  

     
    PAPER

      Vol:
    E93-C No:7
      Page(s):
    1022-1031

    The purpose of this paper is to propose an efficient and effective design scheme to implement compact, high-performance wideband bandpass filters based on a novel compound three-line unit consisting of a stub-loaded short-circuited parallel-coupled three-line structure and two lead lines. Firstly, a simulative investigation is conducted on the transmission characteristics of the proposed coupling unit. The results show that the bandwidth of such structure can be predicted by a symmetric parallel-coupled short-circuited three-line unit, whereas the transmission zeros by a three-section stub composed of the loaded stub, one of the parallel-coupled three lines and the lead line. Accordingly, given specifications, a pseudo-elliptical filter can be designed in an novel three-coupled-line based two-step design scheme: 1. after the derivation of the new closed-form synthesis formulae, a Chebyshev ultra-wideband (UWB) filter is synthesized on a desired passband using symmetric three-line coupling units. 2. By designing the stubs and choosing the proper lengths of the lead lines, multiple transmission zeros are then introduced to improve the skirt and stopband characteristics, whereas the equiripple characteristics are kept in passband. As an example, a UWB bandpass filter covering the Japan's lower UWB band (BW: 3.1-4.8 GHz, FBW: 43%) is designed to describe the proposed design procedure. The measured filtering characteristics agree very well with the theoretical predictions, which validate the effectiveness of the proposed new coupling structure and corresponding filter design technique. In addition, the designed filters exhibit good characteristics, such as steep skirt selectivity, very wide stopbands, a compact size compared with the filter based on short-circuited three-line structure, etc.

  • High-Speed Computation of the Kleene Star in Max-Plus Algebraic System Using a Cell Broadband Engine

    Hiroyuki GOTO  

     
    PAPER-Fundamentals of Information Systems

      Vol:
    E93-D No:7
      Page(s):
    1798-1806

    This research addresses a high-speed computation method for the Kleene star of the weighted adjacency matrix in a max-plus algebraic system. We focus on systems whose precedence constraints are represented by a directed acyclic graph and implement it on a Cell Broadband EngineTM (CBE) processor. Since the resulting matrix gives the longest travel times between two adjacent nodes, it is often utilized in scheduling problem solvers for a class of discrete event systems. This research, in particular, attempts to achieve a speedup by using two approaches: parallelization and SIMDization (Single Instruction, Multiple Data), both of which can be accomplished by a CBE processor. The former refers to a parallel computation using multiple cores, while the latter is a method whereby multiple elements are computed by a single instruction. Using the implementation on a Sony PlayStation 3TM equipped with a CBE processor, we found that the SIMDization is effective regardless of the system's size and the number of processor cores used. We also found that the scalability of using multiple cores is remarkable especially for systems with a large number of nodes. In a numerical experiment where the number of nodes is 2000, we achieved a speedup of 20 times compared with the method without the above techniques.

  • Multilayered Volumetric Composite Right/Left Handed Metamaterial Structures Composed of Dielectric Resonators and Parallel Mesh Plates

    Tetsuya UEDA  Shusuke ADACHI  Naobumi MICHISHITA  Masahiro AKIYAMA  Tatsuo ITOH  

     
    PAPER

      Vol:
    E93-C No:7
      Page(s):
    1063-1071

    Multilayered volumetric composite right/left handed metamaterial structures are investigated. The present structure is composed of conducting mesh plates and dielectric layers including dielectric resonators. The 2-D composite right/left handed metamaterial structure is designed for the in-plane propagation. Propagation mode analysis was made for the volumetric structure under the periodic boundary condition along the normal to the layers as well as for finite number of layered type for comparison. The negative-refractive-index planar lenses were designed and fabricated for the demonstration. It is found from the numerical simulation that the beam focusing through the planar lens with large number of layers is clearly confirmed in both magnitude and phase distribution of the fields. On the other hand, for small number of layers, the beam spot is not found in the magnitude distribution due to the effect of discontinuities between air and designed structure at the top and bottom surfaces, but is still found in the phase distribution. The effect of number of stacked layers on the propagation characteristics is discussed by comparing the numerical simulation results with the measurement.

  • A Study on Compact Wide Bandpass Filter Using Inter-Digital Resonator

    Jumpei YAMAMOTO  Takenori YASUZUMI  Tomoki UWANO  Osamu HASHIMOTO  

     
    BRIEF PAPER

      Vol:
    E93-C No:7
      Page(s):
    1132-1134

    A new type of the wide-band BPF made up of an inter-digital resonator and parallel-coupled lines was proposed. The bandwidth of the inter-digital resonator becomes wider by increasing the number of fingers. The design of the parallel-coupled line was performed by optimazing the structural parameters so that the bandwidth is the same as that of the inter-digital resonator. The measured results of the combination of above elements for the BPF agreed well with the simulated ones such that the insertion loss is less than 0.67 dB and that the sharp skirt characteristics are realized by attenuation poles near the edges of the passband.

  • Moving Picture Coding by Lapped Transform and Edge Adaptive Deblocking Filter with Zero Pruning SPIHT

    Nasharuddin ZAINAL  Toshihisa TANAKA  Yukihiko YAMASHITA  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E93-D No:6
      Page(s):
    1608-1617

    We propose a moving picture coding by lapped transform and an edge adaptive deblocking filter to reduce the blocking distortion. We apply subband coding (SBC) with lapped transform (LT) and zero pruning set partitioning in hierarchical trees (zpSPIHT) to encode the difference picture. Effective coding using zpSPIHT was achieved by quantizing and pruning the quantized zeros. The blocking distortion caused by block motion compensated prediction is reduced by an edge adaptive deblocking filter. Since the original edges can be detected precisely at the reference picture, an edge adaptive deblocking filter on the predicted picture is very effective. Experimental results show that blocking distortion has been visually reduced at very low bit rate coding and better PSNRs of about 1.0 dB was achieved.

  • Efficient Power Network Analysis with Modeling of Inductive Effects

    Shan ZENG  Wenjian YU  Xianlong HONG  Chung-Kuan CHENG  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E93-A No:6
      Page(s):
    1196-1203

    In this paper, an efficient method is proposed to accurately analyze large-scale power/ground (P/G) networks, where inductive parasitics are modeled with the partial reluctance. The method is based on frequency-domain circuit analysis and the technique of vector fitting, and obtains the time-domain voltage response at given P/G nodes. The frequency-domain circuit equation including partial reluctances is derived, and then solved with the GMRES algorithm with rescaling, preconditioning and recycling techniques. With the merit of sparsified reluctance matrix and iterative solving techniques for the frequency-domain circuit equations, the proposed method is able to handle large-scale P/G networks with complete inductive modeling. Numerical results show that the proposed method is orders of magnitude faster than HSPICE, several times faster than INDUCTWISE, and capable of handling the inductive P/G structures with more than 100,000 wire segments.

  • A 1.76 mW, 100 Mbps Impulse Radio UWB Receiver with Multiple Sampling Correlators Eliminating Need for Phase Synchronization in 65-nm CMOS

    Lechang LIU  Zhiwei ZHOU  Takayasu SAKURAI  Makoto TAKAMIYA  

     
    PAPER

      Vol:
    E93-C No:6
      Page(s):
    796-802

    A low power impulse radio ultra-wideband (IR-UWB) receiver for DC-960 MHz band is proposed in this paper. The proposed receiver employs multiple DC power-free charge-domain sampling correlators to eliminate the need for phase synchronization. To alleviate BER degradation due to an increased charge injection in a subtraction operation in the sampling correlator than that of an addition operation, a comparator with variable threshold (=offset) voltage is used, which enables an addition-only operation. The developed receiver fabricated in 1.2 V 65 nm CMOS achieves the lowest energy consumption of 17.6 pJ/bit at 100 Mbps in state-of-the-art correlation-based UWB receivers.

  • OWPA: An Ontology-Based Approach to Adaptable Workflow Participant Assignment

    Jianmei GUO  Yinglin WANG  Jian CAO  

     
    PAPER-Office Information Systems, e-Business Modeling

      Vol:
    E93-D No:6
      Page(s):
    1572-1579

    Adaptable workflow participant assignment (WPA) is crucial to the efficiency and quality of workflow execution. This paper proposes an ontology-based approach to adaptable WPA (OWPA). OWPA introduces domain ontology to organize the enterprise data and uses a well-defined OWPA rule to express an authorization constraint. OWPA can represent more complex authorization constraints by flexibly using the enterprise data, the workflow data, the user-input data, and the built-in functions. By a high-usability interactive interface, OWPA allows users to define and modify the OWPA rules easily without any programming work. Moreover, OWPA is bound to the workflow modeling tool and the workflow monitor respectively to adapt to dynamic workflow modification in workflow definitions and workflow instances. OWPA has been applied in three enterprises in China.

  • Design and Optimization of Transparency-Based TAM for SoC Test

    Tomokazu YONEDA  Akiko SHUTO  Hideyuki ICHIHARA  Tomoo INOUE  Hideo FUJIWARA  

     
    PAPER-Information Network

      Vol:
    E93-D No:6
      Page(s):
    1549-1559

    We present a graph model and an ILP model for TAM design for transparency-based SoC testing. The proposed method is an extension of a previous work proposed by Chakrabarty with respect to the following three points: (1) constraint relaxation by considering test data flow for each core separately, (2) optimization of the cost for transparency as well as the cost for additional interconnect area simultaneously and (3) consideration of additional bypass paths. Therefore, the proposed ILP model can represent various problems including the same problem as the previous work and produce better results. Experimental results show the effectiveness and flexibility of the proposed method compared to the previous work.

  • Evolution Analysis of Parallel Concatenated Coded IDMA Systems

    Hao WANG  Shi CHEN  Xiaokang LIN  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E93-B No:6
      Page(s):
    1620-1623

    The bit-error-rate (BER) performance predicted by the semi-analytical evolution technique proposed by Li Ping et al. becomes inaccurate for parallel concatenated coded interleave-division multiple-access (PCC-IDMA) systems. To solve this problem, we develop a novel evolution technique of such systems. Numerical results show that the predicted performance agrees well with the simulation results, and that this technique is useful for system optimization.

  • A Real-Time Joint Source-Channel Coding Based on a Simplified Modeling of the Residual Video Packet Loss

    Yo-Won JEONG  Jae Cheol KWON  Jae-kyoon KIM  Kyu Ho PARK  

     
    PAPER-Multimedia Systems for Communications

      Vol:
    E93-B No:6
      Page(s):
    1583-1593

    We propose a simplified model of real-time joint source-channel coding, which can be used to adaptively determine the quality-optimal code rate of forward error correction (FEC) coding. The objective is to obtain the maximum video quality in the receiver, while taking time-varying packet loss into consideration. To this end, we propose a simplified model of the threshold set of the residual video packet loss rate (RVPLR). The RVPLR is the rate of residual loss of video packets after channel decoding. The threshold set is defined as a set of discrete RVPLRs in which the FEC code rate must be changed in order to maintain minimum distortion during increases or decreases of channel packet loss. Because the closed form of the proposed model is very simple and has one scene-dependent model parameter, a video sender can be easily implemented with the model. To train the scene-dependent model parameters in real-time, we propose a test-run method. This method accelerates the test-run while remaining sufficiently accurate for training the scene-dependent model parameters. By using the proposed model and test-run, the video sender can always find the optimal code rate on the fly whenever there is a change in the packet loss status in the channel. An experiment shows that the proposed model and test-run can efficiently determine the near-optimal code rate in joint source-channel coding.

1121-1140hit(2741hit)