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[Keyword] RIN(2923hit)

2041-2060hit(2923hit)

  • Development of an IP Library of IEEE-754-Standard Single-Precision Floating-Point Dividers

    Hiroyuki OCHI  Tatsuya SUZUKI  Sayaka MATSUNAGA  Yoichi KAWANO  Takao TSUDA  

     
    PAPER-IP Design

      Vol:
    E86-A No:12
      Page(s):
    3020-3027

    Floating-point units (FPUs) are indispensable in processors, 3D-graphic engines, etc. To improve design productivity of these LSIs, FPU IPs are strongly desired. However, it is impossible to cover wide range of needs by an FPU IP, because there are various kind of options in specifications (e.g., operating frequency, latency, and ability of pipeline operation) and implementations (e.g., hardware algorithms). Thus, multiple IPs are needed even for the same functionality. In this paper, we propose to build an IP Library which consists of large number of FPU IPs with various kind of specifications and implementations, and which has catalogue data that shows not only specifications but also post-layout area and power dissipation of each IP. As the first step of the project, we have developed an IP Library targeted to Rohm 0.35 µm triple-metal process, which consists of 20 IPs for IEEE-754-standard single-precision floating-point division with 5 operating frequencies (50 MHz, 75 MHz, 100 MHz, 125 MHz, and 150 MHz), with two options whether pipelined or not, and with two hardware algorithms (the restoring method and the SRT method). We have also developed a catalogue for the IP Library, which shows post-layout area and power dissipation as well as specification of each IP. We have introduced two metrics "performance-area ratio (MFLOPS/mm2)" and "performance-power ratio (MFLOPS/W)" to afford a good insight into efficiency of implementations. From the catalogue data, the restoring method is, on the average, 1.4 times and 2.3 times better than the SRT method in terms of performance-area ratio and performance-power ratio, respectively. The developed catalogue is usable not only for selection of the optimal IP for a specific application, but also for quantitative analysis at the early stage of architecture design. It is also expected that the catalogue data based on an actual process technology is valuable for education.

  • Statistical Gate-Delay Modeling with Intra-Gate Variability

    Kenichi OKADA  Kento YAMAOKA  Hidetoshi ONODERA  

     
    PAPER-Parasitics and Noise

      Vol:
    E86-A No:12
      Page(s):
    2914-2922

    This paper proposes a model to calculate statistical gate-delay variation caused by intra-chip and inter-chip variabilities. The variation of each gate delay directly influences the circuit-delay variation, so it is important to characterize each gate-delay variation accurately. Every transistor in a gate affects transient characteristics of the gate, so it is indispensable to consider an intra-gate variability for the modeling of gate-delay variation. This effect is not captured in a statistical delay analysis reported so far. Our model considers the intra-gate variability by sensitivity constants. We evaluate our modeling accuracy, and we show some simulated results of a circuit delay variation.

  • Application of Millimeter-Wave Heating to Materials Processing

    Shoji MIYAKE  Yukio MAKINO  

     
    INVITED PAPER

      Vol:
    E86-C No:12
      Page(s):
    2365-2370

    Recently, millimeter-wave energy has attracted much attention as a new and novel energy source for materials processing. In the present paper, several unique features of millimeter-wave heating in materials processing are reviewed briefly and development of materials processing machines by mm-wave radiation is also described. In the application of mm-wave heating, sintering of high quality alumina ceramics having a high bending strength of about 800 MPa are first demonstrated and followed by preparation of aluminum nitride with a high thermal conductivity over 200 W/(mK) at a sintering temperature lower by 473-573 K than the conventional method, by which this processing can be expected to be one of the environment-conscious energy saving processes. A newly developed post-annealing process with mm-wave radiation is described, in which crystallization of amorphous perovskite oxide films prepared by plasma sputtering was attained at temperatures lower than that by the conventional heating and the dielectric constant of post-annealed SrTiO3 (STO) films by mm-wave radiation were drastically improved.

  • An Efficient Analysis of Lossless and Lossy Discontinuities in Waveguide Using Hybrid Numerical Method

    Takeshi SHIRAISHI  Toshio NISHIKAWA  Kikuo WAKINO  Toshihide KITAZAWA  

     
    PAPER

      Vol:
    E86-C No:11
      Page(s):
    2184-2190

    A novel hybrid numerical method, which is based on the extended spectral domain approach combined with the mode-matching method, is applied to evaluate the scattering parameter of waveguide discontinuities. The formulation procedure utilizes the biorthogonal relation in the transformation, and the Green's functions in the spectral domain are obtained easily even in the inhomogeneous lossy regions. The present method does not include the approximate perturbational scheme, and it can evaluate accurately and stably the scattering parameters of either for the thin or thick obstacles made of the wide variety of materials, the lossless dielectrics to highly conductive media, in short computation time. The physical phenomena of transmission through the lossy obstacles are investigated by numerical computations. The results are compared with FEM where FEM computations are feasible, although the FEM computations cannot cover the whole performances of the present method. The good agreement is observed in the corresponding range. The matrix size in this method is smaller than that of other methods. Therefore, the present method is numerically efficient and it would be able to apply for the integrated evaluation of a successive discontinuity. The resonant characteristics of rectangular waveguide cavity are analyzed accurately taking the conductor losses into consideration.

  • Low-Latency Bit-Parallel Systolic Multiplier for Irreducible xm + xn + 1 with GCD(m,n) = 1

    Chiou-Yng LEE  

     
    PAPER-Algorithms and Data Structures

      Vol:
    E86-A No:11
      Page(s):
    2844-2852

    This investigation proposes a new multiplication algorithm in the finite field GF(2m) over the polynomial basis, in which the irreducible xm +xn + 1 with gcd(m,n) = 1 generates the field GF(2m). The algorithm involves two steps--the intermediate multiplication and the modulo reduction. In the first step, the intermediate multiplication algorithm permutes a polynomial to construct the full-bit-parallel systolic intermediate multiplier. The circuit is identical of m2 cells, each cell is identical of one 2-input AND gate, one 2-input XOR gate, and four 1-bit latches. In the second step, based on the results of the intermediate multiplication in the first step, the modulo reduction circuit is built using regular and simple reduction operations. The latency of the proposed multiplier requires m + k + 1 clock cycles, where k = + 1. Notably, the latency can be very low if n is in the range 1 n . For the computing multiplication in GF(2m), the novel multiplier exhibits much lower latency than the existing systolic multipliers, and is well suited to VLSI systems due to their regular interconnection pattern, modular structure and fully inherent parallelism.

  • Multi Criteria Real-Time Scheduling for Manufacturing Systems by Context-Dependent Agents

    Toshiyuki MIYAMOTO  Sadatoshi KUMAGAI  

     
    PAPER

      Vol:
    E86-A No:11
      Page(s):
    2775-2781

    Autonomous distributed manufacturing systems(ADMS) consist of multiple intelligent components with each component acting according to its own judgments. The ADMS objective is to realize more agile and adaptive manufacturing systems. This paper presents the introduction of context-dependent agents (CDAs) in ADMS, and switch strategies depending on system conditions to achieve better performance can be realized by agents that use the same strategies under all system conditions. For the real-time job scheduling problem, the present paper recalls a basic CDA architecture, and presents the results of an extensive empirical evaluation its performance relative to other rule-based schemes based on several common indices for real-time dispatch.

  • A Graph Based Approach for an Extended Resource Planning and Line Balancing Problem

    Toshiyuki MIYAMOTO  Syoji YAMASHITA  Sadatoshi KUMAGAI  Hideaki OHTA  Koichi FUKUMOTO  Yoichi NAGAO  

     
    PAPER

      Vol:
    E86-A No:11
      Page(s):
    2739-2746

    The present paper discusses an assembly line balancing problem (ALBP). ALBP discussed up to now does not consider rack spaces where tools or parts are stored. We introduce an extended resource planning and assembly line balancing problem that takes the rack space into account. An exact search method for solving the problem by using a graph structure, and a heuristics for the method are proposed. The proposed method is evaluated by computational experiments.

  • A New Protocol for Double Auction Based on Homomorphic Encryption

    Wataru OHKISHIMA  Shigeki GOTO  

     
    PAPER

      Vol:
    E86-D No:11
      Page(s):
    2361-2370

    The auction is a popular way of trading. Despite of the popularity of the auction, only a small number of papers have addressed the protocol which realize the double auction. In this paper, we propose a new method of double auction which improves the algorithm of the existing double auction protocol. Our new method is based on the idea of number comparison which is realized by homomorphic encryption. The new method solves the problem of the privacy of losing bids found in the existing algorithm. The buyers and the sellers can embed a random number in their bidding information by the use of the homomorphic encryption. The players in an auction cannot get anyone else's bidding information. The new method is more efficient than the existing ones. Our new method satisfies the criteria for the auction protocol.

  • Greengard-Rokhlin's Fast Multipole Algorithm for Numerical Calculation of Scattering by N Conducting Circular Cylinders

    Norimasa NAKASHIMA  Mitsuo TATEIBA  

     
    PAPER

      Vol:
    E86-C No:11
      Page(s):
    2158-2166

    The boundary element method (BEM), a representative method of numerical calculation of electromagnetic wave scattering, has been used for solving boundary integral equations. Using BEM, however, we finally have to solve a linear system of L equations expressed by dense coefficient matrix. The floating-point operation is O(L2) due to a matrix-vector product in iterative process. Greengard-Rokhlin's fast multipole algorithm (GRFMA) can reduce the operation to O(L). In this paper, we describe GRFMA and its floating-point operation theoretically. Moreover, we apply the fast Fourier transform to the calculation processes of GRFMA. In numerical examples, we show the experimental results for the computation time, the amount of used memory and the relative error of matrix-vector product expedited by GRFMA. We also discuss the convergence and the relative error of solution obtained by the BEM with GRFMA.

  • Bearing Estimation for Spatially Distributed Sources Using Differential Denoising Technique

    Shenjian LIU  Qun WAN  Yingning PENG  

     
    PAPER-Sensing

      Vol:
    E86-B No:11
      Page(s):
    3257-3265

    In this paper, we consider the problem of bearing estimation for spatially distributed sources in unknown spatially-correlated noise. Assumed that the noise covariance matrix is centro-Hermitian, a differential denoising scheme is developed. Combined it with the classic DSPE algorithm, a differential denoising estimator is formulated. Its modified version is also derived. Exactly, the differential processing is first imposed on the covariance matrix of array outputs. The resulting differential signal subspace (DSS) is then utilized to weight array outputs. The noise components orthogonal to DSS are eliminated. Based on eigenvalue decomposition of the covariance matrix of weighted array outputs, the DSPE null spectrum is constructed. The asymptotic performance of the proposed bearing estimator is evaluated in a closed form. Moreover, in order to improve the performance of bearing estimation in case of low signal-to-noise ratio, a modified differential denoising estimator is proposed. Simulation results show the effectiveness of the proposed estimators under the low SNR case. The impacts of angular spread and number of sensors are also investigated.

  • Inverse Scattering of a Two-Dimensional Dielectric Object by Genetic Algorithms

    Chun Jen LIN  Chien-Ching CHIU  Yi-Da WU  

     
    PAPER

      Vol:
    E86-C No:11
      Page(s):
    2230-2236

    In this paper, an efficient optimization algorithm for solving the inverse problem of a two-dimensional lossless homogeneous dielectric object is investigated. A lossless homogeneous dielectric cylinder of unknown permittivity scatters the incident wave in free space and the scattered fields are recorded. Based on the boundary condition and the incident field, a set of nonlinear surface integral equation is derived. The imaging problem is reformulated into optimization problem and the steady-state genetic algorithm is employed to reconstruct the shape and the dielectric constant of the object. Numerical results show that the permittivity of the cylinders can be successfully reconstructed even when the permittivity is fairly large. The effect of random noise on imaging reconstruction is also investigated.

  • Self-Organizing Map for Group Technology Oriented Plant Layout Planning

    Takeshi TATEYAMA  Seiichi KAWATA  Hideaki OHTA  

     
    PAPER

      Vol:
    E86-A No:11
      Page(s):
    2747-2754

    In this paper, a new grouping method for Group Technology using Self-Organizing Map (SOM) is proposed. The purpose of our study is to divide machines in a factory into any number of cells so that the machines in each cell can process a similar set of parts to increase productivity. A main feature of our method is to specify not only the number of the cells but also the maximum and minimum numbers of machines in a cell. Some experimental results show effectiveness of our proposed algorithm.

  • Assessment of Drinking Condition as Preliminary Stage for Rank Evaluation of Cerebral Disease

    Akihiko SUGIURA  Keiichi YONEMURA  

     
    PAPER-Image

      Vol:
    E86-A No:11
      Page(s):
    2860-2867

    Aging is progressing in our country. Cerebral disease poses a serious problem. Viewing this problem objectively, we can say that support of aging and cerebral disease patients is a useful research theme. To the present, we have done rank evaluation of cerebral disease using synthetic face picture images. This study assesses cognitive ability and expression control ability for intoxication, which is known to impair thinking, cognition, and memory ability. We also examine correspondence of intoxication to cerebral disease. Measurement of cognitive ability corresponds to observation of an internal condition; the measurement of expression control ability corresponds to observation of an external condition. In measurement of cognitive ability, we simulated early stage symptoms of vascular dementia in the second stage of BAC. Also, decreased cognitive ability occurs from the first stage of BAC on face recognition to figure and language. Moreover, face test results show significant difference between decrease in the first stage of BAC and one in the second stage of BAC. These results indicate the possibility of rank evaluation and early stage detection of vascular dementia using a face picture image. From measurement of expression control ability, we obtained the result that we can judge whether a subject has reached second stage of BAC by observing an expression's strength of smile. The second stage of BAC shows symptoms similar to those of vascular dementia. We found the possibility that smile is valid as one externally-observable index for detection of cerebral disease.

  • The Performance Enhancement with Multiple Antenna Technology in Indoor-to-Outdoor Communication Systems

    Yong Up LEE  Joong-Hoo PARK  Yeongjun SEO  

     
    LETTER-Wireless Communication Technology

      Vol:
    E86-B No:11
      Page(s):
    3331-3335

    The performance enhancement technology for indoor-to-outdoor wireless communication systems is discussed in this study. In outdoor communication systems, transmitted signals may be severely degraded mainly by multipath fading effect of the channel and this problem can be overcome using conventional multiple antenna technology and array signal processing algorithms. But, since channel characteristics depend on both multipath fading and angle spread in indoor-to-outdoor communication systems, conventional algorithms which do not consider the effect caused by angle spread cannot give good results. In this letter, characteristics of indoor-to-outdoor channels are analyzed and a channel model suitable for this situation is proposed. And a new array antenna processing algorithm exploiting the concept of the mean steering vector is presented and the system performance is analyzed. It can be shown that the proposed algorithm outperforms conventional methods through computer simulations for the case in which signals sent from indoor transmitters arrive at outdoor receivers.

  • An Efficient Handoff-Based Buffering Scheme for Mobile Hosts in IPv6 Network

    ByoungSeob PARK  SungChun KIM  

     
    PAPER

      Vol:
    E86-D No:11
      Page(s):
    2310-2316

    The QoS(Quality of Service) guarantee mechanism is one of critical issues in the wireless network. Real-time applications like VoIP(Voice over IP) in All-IP networks need smooth handoffs in order to minimize or eliminate datagram loss as a Mobile Host(MH) transitions between network links. In this paper, we design a new DB(Dynamic Buffering) mechanism for IPv6 by which an MH can request that the router on its current subnet buffers packets on its behalf while the MH completes registration procedures with the router of a new subnet. Performance results show that our proposed buffering scheme with a dynamic buffer space allocation is quite appropriate for mobile Internet, or the All-IP environment in terms of the datagram loss rate and average waiting time.

  • A Hierarchical Routing Protocol Based on Autonomous Clustering in Ad Hoc Networks

    Tomoyuki OHTA  Munehiko FUJIMOTO  Shinji INOUE  Yoshiaki KAKUDA  

     
    PAPER-Mobile Ad Hoc Networks

      Vol:
    E86-B No:10
      Page(s):
    2902-2911

    Recently, in wired networks, a hierarchical structure has been introduced to improve management and routing. In ad hoc networks, we introduce a hierarchical structure to achieve the same goal. However, it is difficult to introduce the hierarchical structure because all mobile hosts are always moving around the network. So, we proposed the clustering scheme to construct the hierarchical structure before. In this paper, we propose a new hierarchical routing protocol called Hi-TORA based on the clustering scheme. And we show the experimental evaluation of Hi-TORA with respect to the number of control packets, accuracy of packet delivery and hop counts in comparison with TORA.

  • High-Level Synthesis by Ants on a Tree

    Rachaporn KEINPRASIT  Prabhas CHONGSTITVATANA  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E86-A No:10
      Page(s):
    2659-2669

    In this paper an algorithm based on Ant Colony Optimization techniques called Ants on a Tree (AOT) is introduced. This algorithm can integrate many algorithms together to solve a single problem. The strength of AOT is demonstrated by solving a High-Level Synthesis problem. A High-Level Synthesis problem consists of many design steps and many algorithms to solve each of them. AOT can easily integrate these algorithms to limit the search space and use them as heuristic weights to guide the search. During the search, AOT generates a dynamic decision tree. A boosting technique similar to branch and bound algorithms is applied to guide the search in the decision tree. The storage explosion problem is eliminated by the evaporation of pheromone trail generated by ants, the inherent property of our search algorithm.

  • ReVolver/C40: A Scalable Parallel Computer for Volume Rendering--Design and Implementation--

    Shin-ichiro MORI  Tomoaki TSUMURA  Masahiro GOSHIMA  Yasuhiko NAKASHIMA  Hiroshi NAKASHIMA  Shinji TOMITA  

     
    PAPER

      Vol:
    E86-D No:10
      Page(s):
    2006-2015

    This paper describes the architecture of ReVolver/C40 a scalable parallel machine for volume rendering and its prototype implementation. The most important feature of ReVolver/C40 is view-independent real time rendering of translucent 3D object by using perspective projection. In order to realize this feature, the authors propose a parallel volume memory architecture based on the principal axis oriented sampling method and parallel treble volume memory. This paper also discusses the implementation issues of ReVolver/C40 where various kinds of parallelism extracted to achieve high-perfromance rendering are explained. The prototype systems had been developed and their performance evaluation results are explained. As the results of the evaluation of the prototype systems, ReVolver/C40 with 32 parallel volume memory is estimated to achieve more than 10 frame per second for 2563 volume data on 2562 screen by using perspective projection. The authors also review the development of ReVolver/C40 from several view points.

  • Field Configurable Self-Assembly: A New Heterogeneous Integration Technology

    Alan O'RIORDAN  Gareth REDMOND  Thierry DEAN  Mathias PEZ  

     
    INVITED PAPER

      Vol:
    E86-C No:10
      Page(s):
    1977-1984

    Field Configurable Self-assembly is a novel programmable force field based heterogeneous integration technology. Herein, we demonstrate application of the method to rapid, parallel assembly of similar and dissimilar sub-200 µm GaAs-based light emitting diodes at silicon chip substrates. We also show that the method is compatible with post-process collective wiring techniques for fully planar hybrid integration of active devices.

  • A Technique for Constructing Dependable Internet Server Cluster

    Mamoru OHARA  Masayuki ARAI  Satoshi FUKUMOTO  Kazuhiko IWASAKI  

     
    PAPER-Fault Tolerance

      Vol:
    E86-D No:10
      Page(s):
    2198-2208

    An approach is proposed for constructing a dependable server cluster composed only of server nodes with all nodes running the same algorithm. The cluster propagates an IP multicast address as the server address, and clients multicast requests to the cluster. A local proxy running on each client machine enables conventional client software designed for unicasting to communicate with the cluster without having to be modified. Evaluation of a prototype system providing domain name service showed that a cluster using this technique has high dependability with acceptable performance degradation.

2041-2060hit(2923hit)