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[Keyword] CTI(8214hit)

6581-6600hit(8214hit)

  • Frontiers Related with Automatic Shaping of Photonic Crystals

    Osamu HANAIZUMI  Kenta MIURA  Makito SAITO  Takashi SATO  Shojiro KAWAKAMI  Eiichi KURAMOCHI  Satoshi OKU  

     
    INVITED PAPER-Switches and Novel Devices

      Vol:
    E83-C No:6
      Page(s):
    912-919

    Photonic crystals have optical properties characterized by photonic bandgap, large anisotropy and high dispersion, which can be applied to various optical devices. We have proposed an autocloning method for fabricating 2D or 3D photonic crystals and are developing novel structures and functions in photonic crystals. The autocloning is an easy process based on the combination of sputter deposition and sputter etching and is suitable for industry. We have already demonstrated devices or functions such as polarization splitters and surface-normal waveguides. In this paper, we describe our latest work on photonic crystals utilizing the autocloning technology. Phase plates and polarization selective gratings for optical pick-ups are demonstrated utilizing TiO2/SiO2 photonic crystals. The technology to introduce CdS into 3D photonic crystals is also developed and photoluminescence from the introduced CdS is observed, which is the first step to realize luminescent devices with 3D confinement or high polarization controllability.

  • Majority Algorithm: A Formation for Neural Networks with the Quantized Connection Weights

    Cheol-Young PARK  Koji NAKAJIMA  

     
    PAPER

      Vol:
    E83-A No:6
      Page(s):
    1059-1065

    In this paper, we propose the majority algorithm to choose the connection weights for the neural networks with quantized connection weights of 1 and 0. We also obtained the layered network to solve the parity problem with the input of arbitrary number N through an application of this algorithm. The network can be expected to have the same ability of generalization as the network trained with learning rules. This is because it is possible to decide the connection weights, regardless of the size of the training set. One can decide connection weights without learning according to our case study. Thus, we expect that the proposed algorithm may be applied for a real-time processing.

  • Estimation of Camera Rotation Using Quasi Moment Features

    Hiroyuki SHIMAI  Toshikatsu KAWAMOTO  Takaomi SHIGEHARA  Taketoshi MISHIMA  Masaru TANAKA  Takio KURITA  

     
    PAPER

      Vol:
    E83-A No:6
      Page(s):
    1005-1013

    We present two estimation methods for camera rotation from two images obtained by the active camera before and after rotation. Based on the representation of the projected rotation group, quasi moment features are constructed. Camera rotation can be estimated by applying the singular value decomposition (SVD) or Newton's method to tensor quasi moment features. In both cases, we can estimate 3D rotation of the active camera from only two projected images. We also give some experiments for the estimation of the actual active camera rotation to show the effectiveness of these methods.

  • Design of PR Filter Banks for Tree-Structured HDTV Coding

    Her-Chang CHAO  

     
    LETTER-Digital Signal Processing

      Vol:
    E83-A No:6
      Page(s):
    1277-1281

    In this letter, a numerical design approach for FIR diamond-shaped filter banks (DFB) with perfect reconstruction (PR) and low delay for tree-structured HDTV coding is presented. The system delay of the designed DFB can be controlled below the category of the linear-phase. Moreover, the necessary conditions for the system delay of the designed DFB are derived. The considered problem is formulated as the minimization of the real and imaginary parts of weighted peak ripple errors of the designed analysis filters subject to PR constraints. Simulation example is provided to show the efficacy of this proposed design technique.

  • A Simple Phase Compensation Technique with Improved PSRR for CMOS Opamps

    Tetsuro ITAKURA  Tetsuya IIDA  

     
    PAPER

      Vol:
    E83-A No:6
      Page(s):
    941-948

    A simple phase compensation technique with improved power supply rejection ratio (PSRR) for CMOS opamps is proposed. This technique is based on feeding back a current proportional to a derivative of the voltage difference between an output and an input, and does not require a common-gate circuit or a noise-free bias for the circuit. The proposed technique requires only two additional transistors, which are connected to the differential pair of transistors in a cascade manner, and the compensation capacitor is connected to the source node of the additional transistor. Experimental results show an improvement of more than 20 dB in the PSRR at high frequencies, comparing the technique with a Miller compensation. This technique also improves the unity gain frequency and the phase margin from 0.9 MHz and 17 to 1.8 MHz and 44 for 200 pF load capacitance, respectively.

  • Segmentation of Horizontal and Vertical Touching Thai Characters

    Nucharee PREMCHAISWADI  Wichian PREMCHAISWADI  Seinosuke NARITA  

     
    PAPER

      Vol:
    E83-A No:6
      Page(s):
    987-995

    This paper proposes a scheme which combines the conventional technique with a multi-level structure of Thai sentences for detection and segmentation for touching Thai printed characters. The proposed scheme solves problems of both horizontally and vertically touching characters. The complexity of a multi-level structure is employed to classify characters into three zones. The edge detection technique is applied to separate overlapping characters. Then, the horizontal touching characters are determined by using a statistical width of characters. The segmentation point of horizontal touching characters is determined using vertical projection combined with a statistical width of characters. The vertical touching characters are determined by considering the overlapping area of character boundary between zones. The height of line is used to separate the segment of vertical touching characters. Ambiguities are handle by using distinctive features of Thai characters. The effectiveness of the proposed scheme is tested with data from both newspapers and printed documents. The accuracy of 97 and 98 percents are obtained for newspaper and printed documents respectively.

  • Simply Realization of Sound Localization Using HRTF Approximated by IIR Filter

    Hiroshi HASEGAWA  Masao KASUGA  Shuichi MATSUMOTO  Atsushi KOIKE  

     
    PAPER

      Vol:
    E83-A No:6
      Page(s):
    973-978

    HRTFs (head-related transfer functions) are available for sound field reproduction with spatial fidelity, since HRTFs involve the acoustic cues such as interaural time difference, interaural intensity difference and spectral cues that are used for the perception of the location of a sound image. Generally, FIR filters are used in the simulation of HRTFs. However, this method is not useful for a simply system, since the orders of the FIR filters are high. In this paper, we propose a method using IIR filter for simply realization of sound image localization. The HRTFs of a dummy-head were approximated by the following filters: (A) fourth to seventh-order IIR filters and (B) third-order IIR filters. In total, the HRTFs of 24 different directions on the horizontal plane were used as the target characteristics. Sound localization experiments for the direction and the elevation angle of a sound image were carried out for 3 subjects in a soundproof chamber. The binaural signal sounds using the HRTFs simulated by FIR filters and approximated by IIR filters (A) and (B) were reproduced via two loudspeakers, and sound image localization on the horizontal plane was realized. As the result of the experiments, the sound image localization using the HRTFs approximated by IIR filters (A) is the same accuracy as the case of using the FIR filters. This result shows that it is possible to create sound fields with binaural reproduction more simply.

  • An Automatic Signature Scheme Using a Compiler in Distributed Systems

    Whe-Dar LIN  Jinn-Ke JAN  

     
    PAPER-Communication and Computer Architecture/Assurance Systems

      Vol:
    E83-B No:5
      Page(s):
    935-941

    A novel protocol scheme is proposed here to compile a program or run a software package. It is a modification where a file can be detected by checking the consistency of the original file with its accompanying digital signature. When an executable program is created it may get infected with some viruses before the signature is attached to it. The infection cannot be detected by signature verification and the origin of the infection cannot be specified either. We propose a signature scheme that let one can sign right in atomic step after the creation of an executable program. Our security-related and cryptographic protocol is used to establish secure communication over insecure open networks and distributed systems. When a server compiles a source program, the compiler automatically creates both the executable program and its signature. Thus no virus can infect the executable programs without being detected. In our proposed signature scheme, the server signature is created a set of proxy secret integers, which is calculated from a compiler maker's secret key. Each server compiler is possessed by its corresponding client user and it is used only when a server secret value is fed into it. The infections of files can be detected by the ordinary server digital signatures. The proposed signature scheme together with the digital signature against infection in the preprocessing step enables us to specify the origin of the infection. Besides that, we also provide the message recovery capability to recover the original file to save the infected files. The most natural extension of this novel protocol scheme is a server-based signature that integrated together with application packages will allow client and the server to commit themselves to one another.

  • Safety Integrity Levels Model for IEC 61508 -- Examination of Modes of Operation --

    Eiichi KATO  Yoshinobu SATO  

     
    LETTER

      Vol:
    E83-A No:5
      Page(s):
    863-865

    The present paper modifies the algorithm to estimate harmful event frequencies and examines the definition of modes of operation in IEC 61508. As far as the continuous mode concerns, the calculated results coincide with those obtained based on the standard. However, for the intermediate region of medium demand frequencies and/or medium demand durations, the standard gives much higher harmful event frequencies than the real values. In order to avoid this difficulty, a new definition of modes of operation and a shortcut method for allocation of SILs are presented.

  • Mobile Agent-Based Transactions in Open Environments

    Flavio Morais de ASSIS SILVA  Radu POPESCU-ZELETIN  

     
    PAPER-Mobile Agents

      Vol:
    E83-B No:5
      Page(s):
    973-987

    This paper describes a transaction model for open environments based on mobile agents. Mobile agent-based transactions combine mobility and the execution of control flows with transactional semantics. The model presented represents an approach for providing reliability and correctness of the execution of distributed activities, which fulfills important requirements of applications in Open Environments. The presented transaction model is based on a protocol for providing fault tolerance when executing mobile agent-based activities. This protocol is outlined in this paper. With this protocol, if an agent executing an activity at an agency (logical "place" in a distributed agent environment) becomes unreachable for a long time, the execution of the activity can be recovered and continue at another agency. The fault tolerance approach supports "multi-agent activities," i. e. , activities where some of its parts are spawned to execute and migrate asynchronously in relation to other parts. The described transaction model, called the basic (agent-based) transaction model, is an open nested transaction model. By being based on the presented fault tolerance mechanism, subtransactions can be executed asynchronously in relation to their parent transactions and agent-based transactions can explore alternatives in the event of agent unavailability. The model fulfills requirements for supporting the autonomy of organizations in a distributed agent environment.

  • On the Feng-Rao Bound for the L-construction of Algebraic Geometry Codes

    Ryutaroh MATSUMOTO  Shinji MIURA  

     
    LETTER-Information Theory

      Vol:
    E83-A No:5
      Page(s):
    923-926

    We show how to apply the Feng-Rao decoding algorithm and the Feng-Rao bound for the Ω-construction of algebraic geometry codes to the L-construction. Then we give examples in which the L-construction gives better linear codes than the Ω-construction in certain range of parameters on the same curve.

  • An Electronic Soccer Lottery System that Uses Bit Commitment

    Kunio KOBAYASHI  Hikaru MORITA  Mitsuari HAKUTA  Takanori NAKANOWATARI  

     
    PAPER

      Vol:
    E83-D No:5
      Page(s):
    980-987

    This paper proposes an electronic soccer lottery protocol suitable for the Internet environment. Recently, protocols based on public-key schemes such as digital signature have been proposed for electronic voting systems or other similar systems. For a soccer lottery system in particular, it is important to reduce the computational complexity and the amount of communication data required, because we must expect that a large number of tickets will be purchased simultaneously. These problems can be solved by introducing hash functions as the core of protocol. This paper shows a practical soccer lottery system based on bit commitment and hash functions, in which the privacy of prize-winners is protected and illegal acts by the lottery promoter or lottery ticket shops can be revealed.

  • Assurance System Technologies Based on Autonomous Decentralized System for Large Scale Transport Operation Control System

    Kazuo KERA  Keisuke BEKKI  Kazunori FUJIWARA  Fumio KITAHARA  Keiji KAMIJO  

     
    PAPER-Novel Applications

      Vol:
    E83-B No:5
      Page(s):
    1085-1093

    A large-scale primarily public system requires in addition to high reliability, a broad range of applications from control to information services. As construction is phased-in this system must be flexible, changeable and able to grows as the needs arise. However, a changing a system may lead to loss of reliability. A system that is able to change and grow in a reliable and stable manner is called an assurance system and the technology it uses is called assurance technology. This paper describes the basic technology, phased-in system construction and so on of assurance technology based on an autonomous decentralized system. It further discusses application of assurance technology to ATOS as an example of a large-scale transport operation control system. Note: ATOS; Autonomous Decentralized Transport Operation Control System

  • Fault Tolerance in Decentralized Systems

    Brian RANDELL  

     
    INVITED PAPER

      Vol:
    E83-B No:5
      Page(s):
    903-907

    In a decentralised system the problems of fault tolerance, and in particular error recovery, vary greatly depending on the design assumptions. For example, in a distributed database system, if one disregards the possibility of undetected invalid inputs or outputs, the errors that have to be recovered from will just affect the database, and backward error recovery will be feasible and should suffice. Such a system is typically supporting a set of activities that are competing for access to a shared database, but which are otherwise essentially independent of each other--in such circumstances conventional database transaction processing and distributed protocols enable backward recovery to be provided very effectively. But in more general systems the multiple activities will often not simply be competing against each other, but rather will at times be attempting to co-operate with each other, in pursuit of some common goal. Moreover, the activities in decentralised systems typically involve not just computers, but also external entities that are not capable of backward error recovery. Such additional complications make the task of error recovery more challenging, and indeed more interesting. This paper provides a brief analysis of the consequences of various such complications, and outlines some recent work on advanced error recovery techniques that they have motivated.

  • Current-Writing Active-Matrix Circuit for Organic Light-Emitting Diode Display Using a-Si:H Thin-Film-Transistors

    Reiji HATTORI  Tsutomu TSUKAMIZU  Ryusuke TSUCHIYA  Kazunori MIYAKE  Yi HE  Jerzy KANICKI  

     
    LETTER-Electronic Displays

      Vol:
    E83-C No:5
      Page(s):
    779-782

    In this letter, we describe a four thin-film-transistor (TFT) pixel circuit based on hydrogenated amorphous silicon (a-Si:H) technology for the active-matrix organic light-emitting diode (AMOLED) display applications. The circuit uses current-writing mechanism and can automatically adjust the threshold-voltage shifts of both the organic light-emitting diodes (OLEDs) and the TFTs induced by the circuit aging or process variations. Experimental results indicate virtually no variation of the output driving current after long-term bias-temperature-stress (BTS).

  • Verification of a Microcomputer Program Specification Embedded in a Reactive System

    Yasunori ISHIHARA  Kiichiro NINOMIYA  Hiroyuki SEKI  Daisuke TAKAHARA  Yutaka YAMADA  Shigesada OMOTO  

     
    PAPER-Software Engineering

      Vol:
    E83-D No:5
      Page(s):
    1082-1091

    This paper proposes a model checking method for microcomputer programs. To deal with the state explosion problem, we adopt a compositional verification approach. Based on the proposed method, a microcomputer program for a real-life air-conditioner is verified. The program is large enough to cause state explosion. Among fourteen typical properties of the program, five properties are successfully verified by our method.

  • A Roman-Chinese Character Conversion System Correcting Pinyin Spell Errors with Application to the Chinese FEP

    Bin YE  Hirotada KAWAKAMI  Tadahiro MATSUMOTO  Munehiro GOTO  

     
    PAPER-Artificial Intelligence, Cognitive Science

      Vol:
    E83-D No:5
      Page(s):
    1153-1159

    It is not so easy even for the ordinary Chinese to spell the correct Pinyin. Therefore the Pinyin-based Chinese character (Kanji) input system including the Chinese word processor is not easy to use. This paper propose a FEP (Front End Processor) to the Pinyin-based input system which allows the user's slight mistakes due to his ignorance of the spelling or dialect. This FEP uses the similarity of the structure of Kanji to confirm the correct Pinyin.

  • CLASSIC: An O(n2)-Heuristic Algorithm for Microcode Bit Optimization Based on Incompleteness Relations

    Young-doo CHOI  In-Cheol PARK  Chong-Min KYUNG  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E83-A No:5
      Page(s):
    901-908

    This paper presents a heuristic algorithm called CLASSIC for the minimization of the control memory width in microprogrammed processors or the instruction memory width of application-specific VLIW (Very Long Instruction Word) processors. CLASSIC results in nearly optimal solutions with the time complexity of O(n2), where n denotes the number of microoperations. In this paper, we also propose the so-called incompleteness relations which are exploited for the minimization of the control memory width. Experiments using various examples have shown that CLASSIC always achieves smaller microprogram widths compared to the earlier techniques based on the maximal compatibility class or the minimal AND/OR set. The results show that CLASSIC can reduce the control memory width by 34.2% on average compared with a heuristic compatibility class algorithm.

  • Design and Evaluation of Computer Telephony Services in a Distributed Processing Environment

    Shinji MOTEGI  Masaru ENOMOTO  Eiji UTSUNOMIYA  Hiroki HORIUCHI  Toshikane ODA  

     
    PAPER-Novel Applications

      Vol:
    E83-B No:5
      Page(s):
    1075-1084

    TINA (Telecommunications Information Networking Architecture) has been developed to support efficient operation of a wide range of complex services. TINA is effective in building advanced multimedia related services and provides effective solutions for complex service control and management along with a high level of quality of services. However the benefits and effectiveness of TINA for other types of services such as ordinary telephone services and facsimile messaging services are not clear. This paper clarifies how to apply TINA to control and management of computer telephony (CT) services and ordinary telephony services. We designed and implemented CT services in a distributed processing environment (DPE), and in particular a click-to-dial service, as a target for our study. We demonstrate the effectiveness of the design through qualitative and quantitative evaluation. The results of our study show that the distributed processing technique, based on component concepts makes it easy to build and extend CT services, and also that TINA service architecture is applicable to ordinary telephony and advanced CT services.

  • New System Model Based on Autonomous Decentralized System for Highly Productive Processing Equipment

    Takeiki AIZONO  Masahiro OHASHI  Makoto KOGURE  Tohru KIKUNO  

     
    PAPER-Communication and Computer Architecture/Assurance Systems

      Vol:
    E83-B No:5
      Page(s):
    916-924

    High accuracy, high reliability, and high performance have to be simultaneously satisfied to achieve high productivity of the latest processing equipment. High flexibility is also required because many options are available and processing equipment is modified frequently. A high-assurance-system (HAS) model for processing equipment has been developed according to the concept of an Autonomous Decentralized System (ADS). Heterogeneous devices, that have same function and diverse qualities, are utilized to assure the different requirements of high accuracy, high reliability, and high performance simultaneously. The Data Property (DP) and Assurance Manager (AM) are proposed in this model. Different accuracy, reliability, and performance indices characterize each device, and the DP describes the differences of the properties of the data transmitted from these heterogeneous devices. The AM assures not only high reliability but also high performance and high accuracy by utilizing the heterogeneity of data described by the DP. The HAS model was applied to a device-level system used in processing equipment, and its effectiveness was verified by simulating a pressure-control system.

6581-6600hit(8214hit)