• 제목/요약/키워드: Block

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Block Cyclic Reduction 기법에 의한 대형 Sparse Matrix 선형 2계편미분방정식의 효율적인 병렬 해 알고리즘 (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)

  • 이병홍;김정선
    • 한국통신학회논문지
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    • 제15권7호
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    • pp.553-564
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    • 1990
  • 선계2계 편미분 방정식의 일반식에 대한 계수 메트릭스를 (n-1)x(n-1) submatrices로 나누어서 block tridiagonal system으로 변환한 후 cyclic odd-even reduction 기법을 응용하여 large-grain data granularity로서 미지벡타를 구하는 block cyclic reduction 알고리즘을 작성했다. 그런데 이 block cyclic reduction 기법은 매 연산의 단계마다 병렬성이 변하여 병렬처리형 컴퓨터에는 적합하지 못하므로 이 기법을 변형해서 병렬성이 일정하며 실행시간이 보다 단축되는 block cyclic reduction 기법을 제안하고 이 기법에 의한 선형2계 편미분 방정식의 일반식의 解를 구하는 알고리즘을 작성하여 기존의 기법과 비교 고찰했다.

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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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    • 제24권3호
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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.

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

  • 김도현;최경호
    • 스마트미디어저널
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    • 제6권2호
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    • pp.9-14
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    • 2017
  • 무선 환경에서의 패킷 손실은 비디오 통신과정에서 심각한 비디오 품질 저하를 초래한다. 이 논문에서는 블록의 신뢰도와 블록 경계면 매칭을 기반으로 한 비디오 에러 은닉 기술에 대해서 제안한다. 손실된 블록의 모션 정보를 참조 프레임의 동일한 위치에 존재하는 블록의 모션 정보를 복사하여 사용함으로써 임시로 손실된 블록의 잡음을 은닉하고, 블록의 신뢰도를 기준으로 블록의 신뢰도가 낮은 경우에는 추가적으로 블록의 경계면 매칭을 이용하여 모션 벡터를 재탐색하여 잡음 은닉에 대한 정확도를 높이도록 하였다. 실험을 통해서 제안된 기법이 다양한 패킷 손실 환경에서 우수한 에러 은닉 성능을 보임을 확인하였다.

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

  • 이선영;송주명;손준용;신준화
    • 방사선산업학회지
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    • 제6권2호
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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.

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

  • Byung Kook Kim
    • 전자공학회논문지B
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    • 제29B권8호
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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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경부에서의 신경차단시 발생한 경련과 의식소실 및 호흡정지 -증례 보고- (Convulsion, Loss of Consciousness and Respiratory Arrest during Nerve Block at Neck -Two case reports-)

  • 최승택
    • The Korean Journal of Pain
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    • 제11권2호
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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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보간 다항식을 이용한 일반형 블록펄스 적분연산행렬 (A Block Pulse Operational Matrices by Interpolation Polynomial)

  • 이해기;김태훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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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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    • 제어로봇시스템학회 2002년도 ICCAS
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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

  • 강희조;손성찬
    • 디지털콘텐츠학회 논문지
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    • 제5권2호
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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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    • 제16권1_2호
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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.