• Title/Summary/Keyword: Block

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An efficient parallel solution algorithm on the linear second-order partial differential equations with large sparse matrix being based on the block cyclic reduction technique (Block Cyclic Reduction 기법에 의한 대형 Sparse Matrix 선형 2계편미분방정식의 효율적인 병렬 해 알고리즘)

  • 이병홍;김정선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.7
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    • pp.553-564
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    • 1990
  • The co-efficient matrix of linear second-order partial differential equations in the general form is partitioned with (n-1)x(n-1) submartices and is transformed into the block tridiagonal system. Then the cyclic odd-even reduction technique is applied to this system with the large-grain data granularity and the block cyclic reduction algorithm to solve unknown vectors of this system is created. But this block cyclic reduction technique is not suitable for the parallel processing system because of its parallelism chanigng at every computing stages. So a new algorithm for solving linear second-order partical differential equations is presentes by the block cyclic reduction technique which is modified in order to keep its parallelism constant, and to reduce gteatly its execution time. Both of these algoriths are compared and studied.

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MULTI-BLOCK BOUNDARY VALUE METHODS FOR ORDINARY DIFFERENTIAL AND DIFFERENTIAL ALGEBRAIC EQUATIONS

  • OGUNFEYITIMI, S.E.;IKHILE, M.N.O.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.24 no.3
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    • pp.243-291
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    • 2020
  • In this paper, multi-block generalized backward differentiation methods for numerical solutions of ordinary differential and differential algebraic equations are introduced. This class of linear multi-block methods is implemented as multi-block boundary value methods (MB2 VMs). The root distribution of the stability polynomial of the new class of methods are determined using the Wiener-Hopf factorization of a matrix polynomial for the purpose of their correct implementation. Numerical tests, showing the potential of such methods for output of multi-block of solutions of the ordinary differential equations in the new approach are also reported herein. The methods which output multi-block of solutions of the ordinary differential equations on application, are unlike the conventional linear multistep methods which output a solution at a point or the conventional boundary value methods and multi-block methods which output only a block of solutions per step. The MB2 VMs introduced herein is a novel approach at developing very large scale integration methods (VLSIM) in the numerical solution of differential equations.

Boundary Match and Block Reliability Based Error Concealment Algorithm (블록 신뢰도와 경계면 매칭 기반의 잡음 은닉 알고리즘)

  • Kim, Do Hyun;Choi, Kyoung Ho
    • Smart Media Journal
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    • v.6 no.2
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    • pp.9-14
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    • 2017
  • A packet loss in wireless environments causes a severe degradation of video quality in video communications. In this paper, a novel video error concealment algorithm is presented by combining boundary errors and a block reliability measure. The block reliability measure decides the reliability of a block by checking residual errors of a block. In the proposed approach, a motion vector of a missing unreliable block in an inter coded frame is obtained initially based on the motion vector of the same block in the reference frame. Furthermore, if the block in the reference frame is unreliable according to the reliability measure, a new motion vector is decided based on block boundary errors around the initial motion vector. According to our simulations, the proposed approach shows promising results for error concealment in error-prone wireless environments.

Study on the Physicochemical Properties of Crosslinked Poly(Styrene-Butadiene-Styrene) Block Copolymers Prepared by Radiation (방사선으로 제조된 가교 구조의 Poly(Styrene-Butadiene-Styrene) 블록 공중합체 특성에 관한 연구)

  • Lee, Sun-Young;Song, Ju-Myung;Sohn, Joon-Yong;Shin, Junhwa
    • Journal of Radiation Industry
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    • v.6 no.2
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    • pp.171-176
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    • 2012
  • In this study, a crosslinked poly(styrene-butadiene-styrene) [SBS] block copolymers were prepared by using gamma ray irradiation method. The effects of various radiation doses on the degree of crosslinking, thermo property, and morphology of crosslinked SBS block copolymer were investigated. The degree of crosslinking of crosslinked SBS block copolymers were measured by gel-fraction and FT-IR. It was found that the degree of crosslinking of crosslinked SBS block copolymers increases with increase of the irradiation dose while the TGA result shows that the initial degradation temperature of irradiated SBS block copolymer was shifted to lower temperature with increasing irradiation dose. These results indicate that degradation reaction also occurs when SBS block copolymer is exposed to gamma ray irradiation for crosslinking reaction. The SAXS and FE-SEM results indicate that the phase separation of the styrene block and butadiene block was reduced with increasing irradiation dose.

Development of a Process Control Language Using Function Block Configuration (기능블록 구성에 의한 공정제어 언어의 개발)

  • Byung Kook Kim
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.8
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    • pp.24-34
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    • 1992
  • A process control language is developed using function block configuration, to simplify software development for large scale process control systems, and to implement advanced control algorithms with ease. A function block parser and controller is implemented to be suitable for multi-loop control systems having hierachical structure. On-line change of controller parameter is possible, and inclusion of user defined function block is also possible. By adding plant model block, control performance can be checked in advance. Function blocks of the Smith Predicotor, auto-tuners are implemented to demonstrate usefulness of function block configuration.

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Convulsion, Loss of Consciousness and Respiratory Arrest during Nerve Block at Neck -Two case reports- (경부에서의 신경차단시 발생한 경련과 의식소실 및 호흡정지 -증례 보고-)

  • Choi, Seung-Tack
    • The Korean Journal of Pain
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    • v.11 no.2
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    • pp.343-345
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    • 1998
  • Stellate ganglion block and cervical epidural nerve block are frequently practiced in pain clinics because of simple procedure and good effect. Nerve block at head and neck may produce serious complication such as loss of consciousness and cardiac arrest. Blood supply is rich in neck and inadvertent arterial injection of local anesthetics may enter directly into brain. We experienced convulsion and respiratory arrest during SGB and cervical epidural block. The patients were resuscitated successfully and recovered without any adverse effects.

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A Block Pulse Operational Matrices by Interpolation Polynomial (보간 다항식을 이용한 일반형 블록펄스 적분연산행렬)

  • Lee, Hae-Ki;Kim, Tai-Hoon
    • Proceedings of the KIEE Conference
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    • 2004.07e
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    • pp.45-48
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    • 2004
  • This paper presents a new method for finding the Block Pulse series coefficients, deriving the Block Pulse integration operational matrices and generalizing the integration operational matrices which are necessary for the control fields using the Block Pulse functions. In order to apply the Block Pulse function technique to the problems of state estimation or parameter identification more efficiently. it is necessary to find the more exact value of the Block Pulse series coefficients and integral operational matrices.

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Parameter Estimation of The Distributed System via Improved Block Pulse Coefficients Estimation

  • Kim, Tai-hoon;Shim, Jae-sun
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.61.6-61
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    • 2002
  • In these days, Block Pulse functions are used in a variety of fields such as the analysis and controller design of the systems. In applying the Block Pulse function technique to control and systems science, the integral operation of the Block Pulse series plays important roles. This is because differential equations are always involved in the representations of continuous-time models of dynamic systems, and differential operations are always approximated by the corresponding Block Pulse series through integration operational matrices. In order to apply the Block Pulse function technique to the problems of continuous-time dynamic systems more efficiently, it is necessary to find th...

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Block Error Performance Analysis of Mobile Multimedia Communication System in Nakagami fading Channel

  • Kang Heau-Jo;Son Sung-Chan
    • Journal of Digital Contents Society
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    • v.5 no.2
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    • pp.101-105
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    • 2004
  • The block error probabilities of noncoherent frequency shift keying in a Nakagami fading channel are presented in this papaer. The channel fading speed, show or fast. is consider in evaluating block error probabilities. The effectiveness of diversity combing and error correction coding in improving block error performance is examined. The effect of cochannel interference on block error performance is also studied in this paper.

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ON REGULARITY OF BLOCK TRIANGULAR FUZZY MATRICES

  • Meenakshi, A.R.
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.207-220
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    • 2004
  • Necessary and sufficient conditions are given for the regularity of block triangular fuzzy matrices. This leads to characterization of idem-potency of a class of triangular Toeplitz matrices. As an application, the existence of group inverse of a block triangular fuzzy matrix is discussed. Equivalent conditions for a regular block triangular fuzzy matrix to be expressed as a sum of regular block fuzzy matrices is derived. Further, fuzzy relational equations consistency is studied.