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[Keyword] PAR(2741hit)

1101-1120hit(2741hit)

  • Exploration into Single Image Super-Resolution via Self Similarity by Sparse Representation

    Lv GUO  Yin LI  Jie YANG  Li LU  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E93-D No:11
      Page(s):
    3144-3148

    A novel method for single image super resolution without any training samples is presented in the paper. By sparse representation, the method attempts to recover at each pixel its best possible resolution increase based on the self similarity of the image patches across different scale and rotation transforms. The experiments indicate that the proposed method can produce robust and competitive results.

  • A Note on the Branch-and-Cut Approach to Decoding Linear Block Codes

    Shunsuke HORII  Toshiyasu MATSUSHIMA  Shigeichi HIRASAWA  

     
    PAPER-Coding Theory

      Vol:
    E93-A No:11
      Page(s):
    1912-1917

    Maximum likelihood (ML) decoding of linear block codes can be considered as an integer linear programming (ILP). Since it is an NP-hard problem in general, there are many researches about the algorithms to approximately solve the problem. One of the most popular algorithms is linear programming (LP) decoding proposed by Feldman et al. LP decoding is based on the LP relaxation, which is a method to approximately solve the ILP corresponding to the ML decoding problem. Advanced algorithms for solving ILP (approximately or exactly) include cutting-plane method and branch-and-bound method. As applications of these methods, adaptive LP decoding and branch-and-bound decoding have been proposed by Taghavi et al. and Yang et al., respectively. Another method for solving ILP is the branch-and-cut method, which is a hybrid of cutting-plane and branch-and-bound methods. The branch-and-cut method is widely used to solve ILP, however, it is unobvious that the method works well for the ML decoding problem. In this paper, we show that the branch-and-cut method is certainly effective for the ML decoding problem. Furthermore the branch-and-cut method consists of some technical components and the performance of the algorithm depends on the selection of these components. It is important to consider how to select the technical components in the branch-and-cut method. We see the differences caused by the selection of those technical components and consider which scheme is most effective for the ML decoding problem through numerical simulations.

  • Is There Real Fusion between Sensing and Network Technology? -- What are the Problems? Open Access

    Masatoshi ISHIKAWA  

     
    INVITED PAPER

      Vol:
    E93-B No:11
      Page(s):
    2855-2858

    Processing structures required in sensing are designed to convert real-world information into useful information, and there are various restrictions and performance goals depending on physical restrictions and the target applications. On the other hand, network technologies are mainly designed for data exchange in the information world, as is seen in packet communications, and do not go well with sensing structures from the viewpoints of real-time properties, spatial continuity, etc. This indicates the need for understanding the architectures and restrictions of sensor technologies and network technologies when aiming to fuse these technologies. This paper clarifies the differences between these processing structures, proposes some issues to be addressed in order to achieve real fusion of them, and presents future directions toward real fusion of sensor technologies and network technologies.

  • Dispersion of Nanoparticles in Liquid Crystals by Sputtering and Its Effect on the Electrooptic Properties Open Access

    Hiroyuki YOSHIDA  Kosuke KAWAMOTO  Yuma TANAKA  Hitoshi KUBO  Akihiko FUJII  Masanori OZAKI  

     
    INVITED PAPER

      Vol:
    E93-C No:11
      Page(s):
    1595-1601

    The authors describe a method to produce gold nanoparticle-dispersed liquid crystals by means of sputtering, and discuss how the presence of gold nanoparticles affect the electro-optic response of the host liquid crystal. The method exploits the fact that liquid crystals possess low vapor pressures which allow them to undergo the sputtering process, and the target material is sputtered directly on the liquid crystal in a reduced air pressure environment. The sample attained a red-brownish color after sputtering, but no aggregations were observed in the samples kept in the liquid crystal phase. Polarization optical microscopy of the sample placed in a conventional sandwich cell revealed that the phase transition behaviour is affected by the presence of the nanoparticles and that the onset of the nematic phase is observed in the form of bubble-like domains whereas in the pure sample the nematic phase appears after the passing of a phase transition front. Transmission electron microscopy confirmed the presence of single nano-sized particles that were dispersed without forming aggregates in the material. The electro-optic properties of the nanoparticle-dispersed liquid crystal was investigated by measuring the threshold voltage for a twisted-nematic cell. The threshold voltage was found to depend on the frequency of the applied rectangular voltage, and at frequencies higher than 200 Hz, the threshold became lower than the pure samples.

  • Weight Distributions of Multi-Edge Type LDPC Codes

    Kenta KASAI  Tomoharu AWANO  David DECLERCQ  Charly POULLIAT  Kohichi SAKANIWA  

     
    PAPER-Coding Theory

      Vol:
    E93-A No:11
      Page(s):
    1942-1948

    The multi-edge type LDPC codes, introduced by Richardson and Urbanke, present the general class of structured LDPC codes. In this paper, we derive the average weight distributions of the multi-edge type LDPC code ensembles. Furthermore, we investigate the asymptotic exponential growth rate of the average weight distributions and investigate the connection to the stability condition of the density evolution.

  • Unconditionally Secure Oblivious Transfer from Algebraic Signaling over the Gaussian Channel

    Motohiko ISAKA  

     
    PAPER-Cryptography and Information Security

      Vol:
    E93-A No:11
      Page(s):
    2017-2025

    We study the use of the additive white Gaussian noise channel to achieve a cryptographic primitive that is important in secure multiparty computation. A protocol for unconditionally secure oblivious transfer is presented. We show that channel input alphabets with a certain algebraic structure and their partitions are useful in achieving the requirements on the primitive. Signal design for a protocol with high information rate is discussed.

  • Distributed Switch and Stay Combining with Partial Relay Selection over Rayleigh Fading Channels

    Vo Nguyen Quoc BAO  Hyung Yun KONG  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E93-B No:10
      Page(s):
    2795-2799

    Switch and stay combining (SSC) is an attractive diversity technique due to its low complexity and compatibility to resource-constrained wireless networks. This letter proposes a distributed SSC for partial relay selection networks in order to achieve spatial diversity as well as to improve spectral efficiency. Simulation results show that the performance loss (in terms of bit error probability) of the proposed networks relative to partial relay selection networks with selection combining is not substantial.

  • A Stochastic Approach to Design MIMO Antenna with Parasitic Elements Based on Propagation Characteristics

    Naoki HONMA  Kentaro NISHIMORI  Riichi KUDO  Yasushi TAKATORI  Takefumi HIRAGURI  Masato MIZOGUCHI  

     
    PAPER-Antennas

      Vol:
    E93-B No:10
      Page(s):
    2578-2585

    This paper proposes a channel capacity maximization method for Multiple-Input Multiple-Output (MIMO) antennas with parasitic elements. Reactive terminations are connected to the parasitic elements, and the reactance values are determined to achieve stochastically high channel capacity for the environment targeted. This method treats the S-parameter and propagation channel of the antenna, including the parasitic elements, as a combined circuit. The idea of the 'parasitic channel,' which is observed at the parasitic antenna, is introduced to simplify the optimization procedure. This method can significantly reduce the number of necessary measurements of the channel for designing the antenna. As a design example, a bidirectional Yagi-Uda array, which has two driven antennas at both ends of the linear array, is measured in an indoor environment. The resulting design offers enhanced channel capacity mainly due to its improved signal-to-noise ratio compared to the antenna without the parasitic antennas.

  • Oxide Thin Film Transistor Circuits for Transparent RFID Applications Open Access

    Seung Hyun CHO  Sang Woo KIM  Woo Seok CHEONG  Chun Won BYUN  Chi-Sun HWANG  Kyoung Ik CHO  Byung Seong BAE  

     
    INVITED PAPER

      Vol:
    E93-C No:10
      Page(s):
    1504-1510

    Oxide material can make transparent devices with transparent electrodes. We developed a transparent oscillator and rectifier circuits with oxide TFTs. The source/drain and gate electrodes were made by indium thin oxide (ITO), and active layer made by transparent material of IGZO (Indium Gallium Zinc Oxide) on a glass substrate. The RC oscillator was composed of bootstrapped inverters, and 813 kHz oscillation frequency was accomplished at VDD = 15 V. For DC voltage generation from RF, transparent rectifier was fabricated and evaluated. This DC voltage from rectifier powered to the oscillator which operated successfully to create RF. For data transmission, RF transmission was evaluated with RF from the transparent oscillator. An antenna was connected to the oscillator and RF transmission to a receiving antenna was verified. Through this transmission antenna, RF was transmitted to a receiving antenna successfully. For transparent system of RFID, transparent antenna was developed and verified sending and receiving of data.

  • Hybrid Uniform Distribution of Particle Swarm Optimizer

    Junqi ZHANG  Ying TAN  Lina NI  Chen XIE  Zheng TANG  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E93-A No:10
      Page(s):
    1782-1791

    Particle swarm optimizer (PSO) is a stochastic global optimization technique based on a social interaction metaphor. Because of the complexity, dynamics and randomness involved in PSO, it is hard to theoretically analyze the mechanism on which PSO depends. Statistical results have shown that the probability distribution of PSO is a truncated triangle, with uniform probability across the middle that decreases on the sides. The "truncated triangle" is also called the "Maya pyramid" by Kennedy. However, very little is known regarding the sampling distribution of PSO in itself. In this paper, we theoretically analyze the "Maya pyramid" without any assumption and derive its computational formula, which is actually a hybrid uniform distribution that looks like a trapezoid and conforms with the statistical results. Based on the derived density function of the hybrid uniform distribution, the search strategy of PSO is defined and quantified to characterize the mechanism of the search strategy in PSO. In order to show the significance of these definitions based on the derived hybrid uniform distribution, the comparison between the defined search strategies of the classical linear decreasing weight based PSO and the canonical constricted PSO suggested by Clerc is illustrated and elaborated.

  • Design of a Partially-Corporate Feed Double-Layer Slotted Waveguide Array Antenna in 39 GHz Band and Fabrication by Diffusion Bonding of Laminated Thin Metal Plates

    Miao ZHANG  Jiro HIROKAWA  Makoto ANDO  

     
    PAPER-Antennas

      Vol:
    E93-B No:10
      Page(s):
    2538-2544

    Introducing diffusion bonding of laminated thin metal plates to the fabrication of slotted waveguide arrays enlightens the high potential and the feasibility of multi-layer antennas with high-performance. It is a promising process with low cost even for a double-layer antenna, because the number of etching patterns for thin metal plates is only five. In this paper, a double-layer antenna for broadband characteristics is designed in 39 GHz band as demonstration. A 20 20-element antenna is composed of 2 2 sub-arrays by installing a partially-corporate feed circuit in the bottom layer underneath radiating waveguides in the top layer. The five-element sub-arrays in both the feeding and radiating parts are designed first. A new structure for the last slot coupler with shortened termination is also proposed to avoid an extra slot-free region when assembling the neighbor sub-arrays. As the simulation results by HFSS, the maximum gain of 34.55 dBi with the antenna efficiency of 85.5% is estimated at 38.5 GHz. The test antenna is fabricated by the diffusion bonding of thin copper plates. As the measurement results, a very high aperture efficiency of 83.2% with the directivity of 34.5 dBi is realized at the center frequency of 38.75 GHz, where the antenna gain of 34.4 dBi with the high antenna efficiency of 81.4% is achieved. The bandwidth of 5.0% defined as 1 dB down from the maximum gain is achieved.

  • Privacy Preserving Frequency Mining in 2-Part Fully Distributed Setting

    The Dung LUONG  Tu Bao HO  

     
    PAPER

      Vol:
    E93-D No:10
      Page(s):
    2702-2708

    Recently, privacy preservation has become one of the key issues in data mining. In many data mining applications, computing frequencies of values or tuples of values in a data set is a fundamental operation repeatedly used. Within the context of privacy preserving data mining, several privacy preserving frequency mining solutions have been proposed. These solutions are crucial steps in many privacy preserving data mining tasks. Each solution was provided for a particular distributed data scenario. In this paper, we consider privacy preserving frequency mining in a so-called 2-part fully distributed setting. In this scenario, the dataset is distributed across a large number of users in which each record is owned by two different users, one user only knows the values for a subset of attributes, while the other knows the values for the remaining attributes. A miner aims to compute the frequencies of values or tuples of values while preserving each user's privacy. Some solutions based on randomization techniques can address this problem, but suffer from the tradeoff between privacy and accuracy. We develop a cryptographic protocol for privacy preserving frequency mining, which ensures each user's privacy without loss of accuracy. The experimental results show that our protocol is efficient as well.

  • Multilevel Concatenated Space-Time Block Codes

    Shang-Chih MA  

     
    LETTER-Coding Theory

      Vol:
    E93-A No:10
      Page(s):
    1845-1847

    An alternative design for constructing multilevel space-time codes is proposed. For a given space-time block code, we combine several component codes in conjunction with set partitioning of the expanded signal constellation according to the coding gain distance criterion. The error performance of an example code is compared with a traditional multilevel space-time code in computer simulation.

  • Hellinger Distance-Based Parameter Tuning for ε-Filter

    Noriaki SUETAKE  Go TANAKA  Hayato HASHII  Eiji UCHINO  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E93-D No:9
      Page(s):
    2647-2650

    In this letter, we propose a new tuning method of ε value, which is a parameter in the ε-filter, using a metric between signal distributions, i.e., Hellinger distance. The difference between the input and output signals is evaluated using Hellinger distance and used for the parameter tuning in the proposed method.

  • 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.

  • Performance of MPEG-4 Transmission over SCTP Multi-Streaming in Wireless Networks

    Li WANG  Ken'ichi KAWANISHI  

     
    PAPER-Internet

      Vol:
    E93-B No:9
      Page(s):
    2336-2347

    Stream Control Transmission Protocol (SCTP) is a new transport layer protocol for the next generation Internet. SCTP is a connection-oriented protocol that carries over TCP's features but also supports UDP-like message-oriented data transmission. In this paper, we make use of SCTP's multi-streaming feature to transmit MPEG-4 video efficiently, and evaluate its transmission performance under the policy with/without differentiated retransmission. Moreover, to enhance the communication quality, we extend SCTP multi-streaming to realize selective retransmission policy. Our extension utilizes packet-by-packet timestamps to control retransmission of lost packets. By computer simulation, we show that SCTP can (1) improve the video quality by exploiting the multi-streaming and partial reliability features, (2) enhance the video transmission quality by adjusting SCTP fast retransmit threshold, and (3) SCTP with our selective retransmission extension can further improve the whole performance.

  • 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.

  • The Discrimination of Contact Failure Mechanisms by Analyzing the Variations of Time Parameters for Relays

    Shujuan WANG  Qiong YU  Guofu ZHAI  

     
    PAPER

      Vol:
    E93-C No:9
      Page(s):
    1437-1442

    Usually the contact voltage drop or contact resistance of electromagnetic relays is observed only to identify if the contacts are failure or not on the manufactures' life tests. However, it is difficult to reveal the contact performance degradation because the variation of contact resistance may not be obvious. In this paper, a new life test technology was investigated to analyze the contact failure mechanisms and degenerative processes of electromagnetic relays by measuring their time parameters including closing time, opening time, over-travel time, rebound duration and gap time during each operation. Moreover, for the purpose of verifying the time parameters, the contact motion and contact morphology during life test were record by using a high speed camera. Both the variations of time parameters and information obtained from photos taken by high speed camera show that it involves three different degenerative phases during the whole life of a relay. The results also indicate this method is an effective technology to discriminate and diagnose the failure mechanisms for electromagnetic relays.

  • Cross-Layer QoS Control for Distributed Video Coding

    Chul Keun KIM  Doug Young SUH  Gwang-Hoon PARK  

     
    LETTER-Multimedia Systems for Communications

      Vol:
    E93-B No:9
      Page(s):
    2485-2488

    We propose a new channel adaptive distributed video coding algorithm, which is adaptive to time-varying available bitrate and packet loss ratio. The proposed method controls the quantization parameter according to channel condition of especially error-prone mobile channel. Simulation shows that the proposed algorithm outperforms the conventional rate-control-only algorithm.

  • Extended Single Parity Check Product Codes that Achieve Close-to-Capacity Performance in High Coding Rate

    Akira SHIOZAKI  Masashi KISHIMOTO  Genmon MARUOKA  

     
    LETTER-Coding Theory

      Vol:
    E93-A No:9
      Page(s):
    1693-1696

    This letter proposes extended single parity check product codes and presents their empirical performances on a Gaussian channel by belief propagation (BP) decoding algorithm. The simulation results show that the codes can achieve close-to-capacity performance in high coding rate. The code of length 9603 and of rate 0.96 is only 0.77 dB away from the Shannon limit for a BER of 10-5.

1101-1120hit(2741hit)