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[Keyword] SI(16314hit)

15501-15520hit(16314hit)

  • Extraction of Glossiness of Curved Surfaces by the Use of Spatial Filter Simulating Retina Function

    Seiichi SERIKAWA  Teruo SHIMOMURA  

     
    PAPER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E77-D No:3
      Page(s):
    335-342

    Although the perception of gloss is based on human visual perception, some methods for extracting glossiness, in contrast to human ability, have been proposed involving curved surfaces. Glossiness defined in these methods, however, does not correspond with psychological glossiness perceived by the human eye over the wide range from relatively low gloss to high gloss. In addition, the obtained glossiness in these methods changes remarkably when the curvature radius of the high-gloss object becomes larger than 10mm. In reality, psychological glossiness does not change. These methods, furthermore, are available only for spherical objects. A new method for extracting glossiness is proposed in this study. For the new definition of glossiness, a spatial filter which simulates human retina function is utilized. The light intensity distribution of the curved object is convoluted with the spatial filter. The maximum value Hmax of the convoluted distribution has a high correlation with psychological glossiness Gph. From the relationship between Gph and Hmax, new glossiness Gf is defined. The gloss-extraction equipment consists of a light source, TV camera, an image processor and a personal computer. Cylinders with the curvature radii of 3-30 mm are used as the specimens in addition to spherical balls. In all specimens, a strong correlation, with a correlation coefficient of more than 0.97, has been observed between Gf and Gph over a wide range. New glossiness Gf conforms to Gph even if the curvature radius in more than 10 mm. Based on these findings, it is found that this method for extracting glossiness is useful for the extraction of glossiness of spherical and cylindrical objects over a wide range from relatively low gloss to high gloss.

  • Automatic Tracing of Transistor-Level Performance Faults with CAD-Linked Electron Beam Test System

    Katsuyoshi MIURA  Koji NAKAMAE  Hiromu FUJIOKA  

     
    PAPER-Computer Aided Design (CAD)

      Vol:
    E77-A No:3
      Page(s):
    539-545

    An automatic tracing algorithm of the transistor-level performance faults in the waveform-based approach with CAD-linked electron beam test system which utilizes a transistor-level circuit data in CAD database is proposed. Performance faults mean some performance measure such as the temporal parameters (rise time, fall time and so on) lies outside of the specified range in a VLSI. Problems on automatic fault tracing in the transistor level are modeled by using graphs. Combinational circuits which consist of MOS transistors are considered. A single fault is assumed to be in a circuit. The algorithm utilizes Depth-First Search algorithm where faulty upstream interconnections are searched as deeply as possible. Treatment of the faults on downstream interconnections and on unmeasurable interconnections is given. Application of this algorithm to the 2k-transistor block of a CMOS circuit showed its validity in the simulation.

  • Lower Bounds on Size of Periodic Functions in Exclusive-OR Sum-of-Products Expressions

    Yasuaki NISHITANI  Kensuke SHIMIZU  

     
    PAPER-Computer Aided Design (CAD)

      Vol:
    E77-A No:3
      Page(s):
    475-482

    This paper deals with the size of switching functions in Exclusive-OR sum-of-products expressions (ESOPs). The size is the number of products in ESOP. There are no good algorithms to find an exact minimum ESOP. Since the exact minimization algorithms take a time in double exponential order, it is almost impossible to minimize ESOPs for an arbitrary n-variable functions with n5. Then,it is necessary to study the size of some concrete functions. These concrete functions are useful for testing heuristic minimization algorithms. In this paper we present the lower bounds on size of periodic functions in ESOPs. A symmetric function is said to be periodic when the vector of weights of inputs X such that f(X)1 is periodic. We show that the size of a 2t+1-periodic function with rank r is proportional to n2t+r, where t0 and 0r2t, i.e., in polynomial order,and thet the size of a (2s+1)2t-periodic function with s0 and t0 is greater than or equal to (3/2)n-(2s+1)2t, i.e., in exponential order. The concrete function the size of which is greater than or equal to 32(3/2)n-8 is presented. This function requires the largest size among the concrete functions the sizes of which are known. Some results for non-periodic symmetric functions are also given.

  • Mixed Mode Circuit Simulation Using Dynamic Network Separation and Selective Trace

    Masakatsu NISHIGAKI  Nobuyuki TANAKA  Hideki ASAI  

     
    PAPER-Modeling and Simulation

      Vol:
    E77-A No:3
      Page(s):
    454-460

    For the efficient circuit simulation, several direct/relaxation-based mixed mode simulation techniques have been studied. This paper proposes the combination of selective trace, which is well-known in the logic simulation, with dynamic network separation. In the selective trace method, the time points to be analyzed are selected for each subcircuit. Since the separation technique enables the analysis of each subcircuit independently, it is possible to skip solving the latent subcircuits, according to selective trace. Selecting the time points in accordance with activity of each subcircuit is analogous to multirate numerical integration technique used in the waveform relaxation algorithm.

  • A Circuit Partitioning Approach for Parallel Circuit Simulation

    Tetsuro KAGE  Fumiyo KAWAFUJI  Junichi NIITSUMA  

     
    PAPER-Modeling and Simulation

      Vol:
    E77-A No:3
      Page(s):
    461-466

    We have studied a circuit partitioning approach in the view of parallel circuit simulation on a MIMD parallel computer. In parallel circuit simulation, a circuit is partitioned into equally sized subcircuits while minimizing the number of interconnection nodes. Besides circuit partitioning time should be short enough compared with the total simulation time. From the details of circuit simulation time, we found that balancing subcircuits is critical for low parallel processing, whereas minimizing the interconnection nodes is critical for highly parallel processing. Our circuit partitioning approach consists of four steps: Grouping transistors, initial partitioning the transistor-groups, minimizing the number of interconnection nodes, and balancing the subcircuits. It is based on an algorithmic approach, and can directly control the tradeoffs between balancing subcircuits and minimizing the interconnection nodes by adjusting the parameters. We partitioned a test circuit with 3277 transistors into 4, 9, ... , 64 subcircuits, and did parallel simulations using PARACS, our parallel circuit simulator, on an AP1000 parallel computer. The circuit partitioning time was short enough-less than 3 percent of the total simulation time. The highest performance of parallel analysis using 49 processors was 16 times that of a single processor, and that for total simulation was 9 times.

  • Comparison of Classifiers in Small Training Sample Size Situations for Pattern Recognition

    Yoshihiko HAMAMOTO  Shunji UCHIMURA  Shingo TOMITA  

     
    LETTER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E77-D No:3
      Page(s):
    355-357

    The main problem in statistical pattern recognition is to design a classifier. Many researchers point out that a finite number of training samples causes the practical difficulties and constraints in designing a classifier. However, very little is known about the performance of a classifier in small training sample size situations. In this paper, we compare the classification performance of the well-known classifiers (k-NN, Parzen, Fisher's linear, Quadratic, Modified quadratic, Euclidean distance classifiers) when the number of training samples is small.

  • Extended Pseudo-Biorthogonal Bases of Type O and Type L

    Nasr-Eddine BERRACHED  Hidemitsu OGAWA  

     
    PAPER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E77-D No:3
      Page(s):
    299-305

    As a generalization of the concept of pseudo-biorthogonal bases (PBOB), we already presented in Ref. [3] the theory of the so-called extended pseudo-biorthogonal bases (EPBOB). We introduce in this paper two special types of EPBOB called EPBOB's of type O and of type L. This paper discusses characterizations, construction methods, inherent properties, and mutual relations of these types of EPBOB.

  • Parallel and Modular Structures for FIR Digital Filters

    Saed SAMADI  Akinori NISHIHARA  Nobuo FUJII  

     
    PAPER-Digital Signal Processing

      Vol:
    E77-A No:3
      Page(s):
    467-474

    The scope of this paper is the realization of FIR digital filters with an emphasis on linear phase and maximally flat cases. The transfer functions of FIR digital filters are polynomials and polynomial evaluation algorithms can be utilized as realization schemes of these filters. In this paper we investigate the application of a class of polynomial evaluation algorithms called "recursive triangles" to the realization of FIR digital filters. The realization of an arbitrary transfer function using De Casteljau algorithm, a member of the recursive triangles used for evaluating Bernstein polynomials, is studied and it is shown that in some special and important cases it yields efficient modular structures. Realization of two dimensional filters based on Bernstein approximation is also considered. We also introduce recursive triangles for evaluating the power basis representation of polynomials and give a new multiplier-less maximally flat structure based on them. Finally, we generalize the structure further and show that Chebyshev polynomials can also be evaluated by the triangles. This is the triangular counterpart of the well-known Chebyshev structure. In general,the triangular structures yield highly modular digital filters that can be mapped to an array of concurrent processors resulting in high speed and effcient filtering specially for maximally flat transfer functions.

  • New Technologies of KrF Excimer Laser Lithography System in 0.25 Micron Complex Circuit Patterns

    Masaru SASAGO  Takahiro MATSUO  Kazuhiro YAMASHITA  Masayuki ENDO  Kouji MATSUOKA  Taichi KOIZUMI  Akiko KATSUYAMA  Noboru NOMURA  

     
    PAPER-Process Technology

      Vol:
    E77-C No:3
      Page(s):
    416-424

    New critical-dimension controlling technique of off-axis illumination for aperiodic patterns has been developed. By means of arranging not-imaging additional pattern near 0.25 micron isolated patterns, the depth of focus of an isolated pattern was improved as well as the periodic patterns. Simulation and experimental results were verified on a 0.48 numerical-aperture, KrF excimer laser stepper. Using new deep-ultra-violet hardening technique for chemically amplified positive resist, the critical dimension loss of resist pattern was prevented. 0.25 micron design rule pattern was obtained with excellent mask linearity without critical-dimension-loss. The combination techniques are achieved quarter micron design rule complex circuit pattern layouts.

  • Throttled-Buffer Asynchronous Switch for ATM

    Kenneth J. SCHULTZ  P. Glenn GULAK  

     
    PAPER

      Vol:
    E77-B No:3
      Page(s):
    351-358

    Asynchronous Transfer Mode (ATM) shared buffer switches have numerous advantages, but have the principal disadvantage that all switch traffic must pass through the bottleneck of a single memory. To achieve the most efficient usage of this bottleneck, the shared buffer is made blockable, resulting in a switch architecture that we call "throttled-buffer", which has several advantageous properties. Shared buffer efficiency is maximized while decreasing both capacity and power requirements. Asynchronous operation is possible, whereby peak link data rates are allowed to approach the aggregate switch rate. Multicasting is also efficiently supported. The architecture and operation of this low-cost switch are described in detail.

  • Multimedia Communication Protocols and Services for Broadband Private Networks

    Shiro SAKATA  

     
    INVITED PAPER

      Vol:
    E77-B No:3
      Page(s):
    283-293

    There has been growing interest in Broadband ISDN (B-ISDN) based on ATM (Asynchronous Transfer Mode) technologies, since ATM is expected to support a wide range of applications through high-speed and flexible multimedia communication capabilities. This paper reviews and discusses technical issues on multimedia communication protocols and services from the integration points of view of computer and communication technologies. An ISDN-based distributed multimedia and multi-party desktop conference system called MERMAID is introduced as an example which offers highly-sophisticated functions for remote collaborations among multiple users. This system, which was developed in early 1989 and has been used for daily research work since then, involves B-ISDN key technologies related to multimedia and multicast protocols, and computer architecture for groupware applications.

  • Influences of Magnesium and Zinc Contaminations on Dielectric Breakdown Strength of MOS Capacitors

    Makoto TAKIYAMA  Susumu OHTSUKA  Tadashi SAKON  Masaharu TACHIMORI  

     
    PAPER-Process Technology

      Vol:
    E77-C No:3
      Page(s):
    464-472

    The dielectric breakdown strength of thermally grown silicon dioxide films was studied for MOS capacitors fabricated on silicon wafers that were intentionally contaminated with magnesium and zinc. Most of magnesium was detected in the oxide film after oxidation. Zinc, some of which evaporated from the surface of wafers, was detected only in the oxide film. The mechanism of the dielectric degradation is dominated by formation of metal silicates, such as Mg2SiO4 (Forsterite) and Zn2SiO4 (Wilemite). The formation of metal silicates has no influence on the generation lifetime of minority carriers, however, it provides the flat-band voltage shift less than 0.3 eV, and forces to increase the density of deep surface states with the zinc contamination.

  • Degradation Mechanisms of Thin Film SIMOX SOI-MOSFET Characteristics--Optical and Electrical Evaluation--

    Mitsuru YAMAJI  Kenji TANIGUSHI  Chihiro HAMAGUCHI  Kazuo SUKEGAWA  Seiichiro KAWAMURA  

     
    PAPER-Device Technology

      Vol:
    E77-C No:3
      Page(s):
    373-378

    Optical and electrical measurements of thin film n-channel SOI-MOSFETs reveal that the exponential tail in photon emission spectra originates from electron-hole recombination. Bremsstrahlung radiation model as a physical mechanism of photon emission was experimentally negated. Negative threshold voltage shift at the initial stage of high field stress is found to be caused by hole trapping in buried oxide. Subsequent turnover characteristics is explained by a competing process between electron trapping in the front gate oxide and hole trapping in the buried oxide. As to the degradation of transconductance, generated surface state as well as trapped holes in the buried oxide which reduce vertical electric field in SOI film are involved in the complicate degradation of transconductance.

  • PEAS-I: A Hardware/Software Codesign System for ASIP Development

    Jun SATO  Alauddin Y. ALOMARY  Yoshimichi HONMA  Takeharu NAKATA  Akichika SHIOMI  Nobuyuki HIKICHI  Masaharu IMAI  

     
    PAPER-Computer Aided Design (CAD)

      Vol:
    E77-A No:3
      Page(s):
    483-491

    This paper describes the current implementation and experimental results of a hardware/software codesign system for ASIP (Application Specific Integrated Processor) development: the PEAS-I System. The PEAS-I system accepts a set of application programs written in C language, associated data set, module database, and design constraints such as chip area and power consumption. The system then generates an optimized CPU core design in the form of an HDL as well as a set of application program development tools such as a C compiler, an assembler and a simulator. Another important feature of the PEAS-I system is that the system is able to give accurate estimations of chip area and performance before the detailed design of the ASIP is completed. According to the experimental results, the PEAS-I system has been found to be highly effective and efficient for ASIP development.

  • Stochastic Interpolation Model Scheme and Its Application to Statistical Circuit Analysis

    Jin-Qin LU  Kimihiro OGAWA  Masayuki TAKAHASHI  Takehiko ADACHI  

     
    PAPER-Modeling and Simulation

      Vol:
    E77-A No:3
      Page(s):
    447-453

    IC performance simulation for statistical purpose is usually very time-consuming since the scale and complexity of IC have increased greatly in recent years. A common approach for reduction of simulation cost is aimed at the nature of simple modeling instead of actual circuit performance simulations. In this paper,a stochastic interpolation model (SIM) scheme is proposed which overcomes the drawbacks of the existing polynomial-based approximation schemes. First,the dependence of the R2press statistic upon a parameter in SIM is taken into account and by maximizing R2press this enables SIM to achieve the best approximation accuracy in the given sample points without any assumption on the sample data. Next, a sequential sampling strategy based on variance analysis is described to effectively construct SIM during its update process. In each update step, a new sample point with a maximal value of variance is added to the former set of the sample points. The update process will be continued until the desired approximation accuracy is reached. This would eventually lead to the realization of SIM with a quite small number of sample points. Finally, the coefficient of variance is introduced as another criterion for approximation accuracy check other than the R2press statistic. The effectiveness of presented implementation scheme is demonstrated by several numerical examples as well as a statistical circuit analysis example.

  • Temperature Adaptive Voltage Reference Network for Realizing a Transconductance with Low Temperature Sensitivity

    Rabin RAUT  

     
    LETTER-Integrated Electronics

      Vol:
    E77-C No:3
      Page(s):
    515-518

    A technique to realize a transconductance which is relatively insensitive over temperature variations is reported. Simulation results with MOS and bipolar transistors indicate substantial improvement in temperature insensitivity over a range exceeding 100 degrees Celsius. It should find useful applications in analog LSI/VLSI systems operating over a wide range of temperature.

  • Fast Algorithms for Minimum Covering Run Expression

    Supoj CHINVEERAPHAN  AbdelMalek B.C. ZIDOURI  Makoto SATO  

     
    PAPER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E77-D No:3
      Page(s):
    317-325

    The Minimum Covering Run (MCR) expression used for representing binary images has been proposed [1]-[3]. The MCR expression is an adaptation from horizontal and vertical run expression. In the expression, some horizontal and vertical runs are used together for representing binary images in which total number of them is minimized. It was shown that, sets of horizontal and vertical runs representing any binary image could be viewed as partite sets of a bipartite graph, then the MCR expression of binary images was found analogously by constructing a maximum matching as well as a minimum covering in the corresponding graph. In the original algorithm, the most efficient algorithm, proposed by Hopcroft, solving the graph-theoretical problems mentioned above, associated with the Rectangular Segment Analysis (RSA) was used for finding the MCR expression. However, the original algorithm still suffers from a long processing time. In this paper, we propose two new efficient MCR algorithms that are beneficial to a practical implementation. The new algorithms are composed of two main procedures; i.e., Partial Segment Analysis (PSA) and construction of a maximum matching. It is shown in this paper that the first procedure which is directly an improvement to the RSA, appoints well a lot of representative runs of the MCR expression in regions of text and line drawing. Due to the PSA, the new algorithms reduce the number of runs used in the technique of solving the matching problem in corresponding graphs so that satisfactory processing time can be obtained. To clarify the validity of new algorithms proposed in this paper, the experimental results show the comparative performance of the original and new algorithms in terms of processing time.

  • Automatic Color Segmentation Method Using a Neural Network Model for Stained Images

    Hironori OKII  Noriaki KANEKI  Hiroshi HARA  Koichi ONO  

     
    PAPER-Bio-Cybernetics

      Vol:
    E77-D No:3
      Page(s):
    343-350

    This paper describes a color segmentation method which is essential for automatic diagnosis of stained images. This method is applicable to the variance of input images using a three-layered neural network model. In this network, a back-propagation algorithm was used for learning, and the training data sets of RGB values were selected between the dark and bright images of normal mammary glands. Features of both normal mammary glands and breast cancer tissues stained with hematoxylin-eosin (HE) staining were segmented into three colors. Segmented results indicate that this network model can successfully extract features at various brightness levels and magnifications as long as HE staining is used. Thus, this color segmentation method can accommodate change in brightness levels as well as hue values of input images. Moreover, this method is effective to the variance of scaling and rotation of extracting targets.

  • Minimizing the Data Transfer in Evaluating an Expression in a Distributed-Memory Parallel-Processing System

    Hiroshi OHTA  Kousuke SAKODA  Koichiro ISHIHARA  

     
    PAPER-Computer Systems

      Vol:
    E77-D No:3
      Page(s):
    288-298

    In a distributed-memory parallel-processing system, the overhead of data transfer among the processors is so large that it is important to reduce the data transfer. We consider the data transfer in evaluating an expression consisting of data distributed among the processors. We propose some algorithms which assign the operators in the expression to the processors so as to minimize the number or the cost of data transfers, on the condition that the data allocation to the processors is given. The basic algorithm is given at first, followed by some variations.

  • Finding All Solutions of Piecewise-Linear Resistive Circuits Containing Neither Voltage nor Current Controlled Resistors

    Kiyotaka YAMAMURA  

     
    LETTER-Nonlinear Circuits and Systems

      Vol:
    E77-A No:3
      Page(s):
    573-576

    Recently, efficient algorithms that exploit the separability of nonlinear mappings have been proposed for finding all solutions of piecewise-linear resistive circuits. In this letter, it is shown that these algorithms can be extended to circuits containing piecewise-linear resistors that are neither voltage nor current controlled. Using the parametric representation for these resistors, the circuits can be described by systems of nonlinear equations with separable mappings. This separability is effectively exploited in finding all solutions. A numerical example is given, and it is demonstrated that all solutions are computed very rapidly by the new algorithm.

15501-15520hit(16314hit)