• 제목/요약/키워드: computer algorithms

검색결과 3,810건 처리시간 0.033초

Formal Analysis of Distributed Shared Memory Algorithms

  • Muhammad Atif;Muhammad Adnan Hashmi;Mudassar Naseer;Ahmad Salman Khan
    • International Journal of Computer Science & Network Security
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    • 제24권4호
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    • pp.192-196
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    • 2024
  • The memory coherence problem occurs while mapping shared virtual memory in a loosely coupled multiprocessors setup. Memory is considered coherent if a read operation provides same data written in the last write operation. The problem is addressed in the literature using different algorithms. The big question is on the correctness of such a distributed algorithm. Formal verification is the principal term for a group of techniques that routinely use an analysis that is established on mathematical transformations to conclude the rightness of hardware or software behavior in divergence to dynamic verification techniques. This paper uses UPPAAL model checker to model the dynamic distributed algorithm for shared virtual memory given by K.Li and P.Hudak. We analyse the mechanism to keep the coherence of memory in every read and write operation by using a dynamic distributed algorithm. Our results show that the dynamic distributed algorithm for shared virtual memory partially fulfils its functional requirements.

I-Tree: A Frequent Patterns Mining Approach without Candidate Generation or Support Constraint

  • Tanbeer, Syed Khairuzzaman;Sarkar, Jehad;Jeong, Byeong-Soo;Lee, Young-Koo;Lee, Sung-Young
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2007년도 춘계학술발표대회
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    • pp.31-33
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    • 2007
  • Devising an efficient one-pass frequent pattern mining algorithm has been an issue in data mining research in recent past. Pattern growth algorithms like FP-Growth which are found more efficient than candidate generation and test algorithms still require two database scans. Moreover, FP-growth approach requires rebuilding the base-tree while mining with different support counts. In this paper we propose an item-based tree, called I-Tree that not only efficiently mines frequent patterns with single database scan but also provides multiple mining scopes with multiple support thresholds. The 'build-once-mine-many' property of I-Tree allows it to construct the tree only once and perform mining operation several times with the variation of support count values.

Fuzzy systems, neural networks and genetic algorithms

  • Lee, Hyung-Kwang;Lee, Jee-Hyong
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 1999년도 가을 학술발표논문집 Vol.26 No.2 (2)
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    • pp.327-332
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    • 1999
  • Fuzzy systems, neural networks and genetic algorithms have different origins and thus have differently developed their own unique characteristics. These characteristics can be used as a good complement to the others. Therefore, many researches have been devoted to not only these techniques but also fusion of them. This paper briefly summarizes these three techniques and surveys the researches on fusion of them.

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POLYNOMIAL CONVERGENCE OF PREDICTOR-CORRECTOR ALGORITHMS FOR SDLCP BASED ON THE M-Z FAMILY OF DIRECTIONS

  • Chen, Feixiang;Xiang, Ruiyin
    • Journal of applied mathematics & informatics
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    • 제29권5_6호
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    • pp.1285-1293
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    • 2011
  • We establishes the polynomial convergence of a new class of path-following methods for semidefinite linear complementarity problems (SDLCP) whose search directions belong to the class of directions introduced by Monteiro [9]. Namely, we show that the polynomial iteration-complexity bound of the well known algorithms for linear programming, namely the predictor-corrector algorithm of Mizuno and Ye, carry over to the context of SDLCP.

An Intelligent New Dynamic Load Redistribution Mechanism in Distributed Environments

  • Lee, Seong-Hoon
    • International Journal of Contents
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    • 제3권1호
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    • pp.34-38
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    • 2007
  • Load redistribution is a critical resource in computer system. In sender-initiated load redistribution algorithms, the sender continues to send unnecessary request messages for load transfer until a receiver is found while the system load is heavy. These unnecessary request messages result in inefficient communications, low CPU utilization, and low system throughput in distributed systems. To solve these problems, we propose a genetic algorithm based approach for improved sender-initiated load redistribution in distributed systems. Compared with the conventional sender-initiated algorithms, the proposed algorithm decreases the response time and task processing time.

컴퓨터 통신망의 경로 및 흐름제어 효과 (Effect of Routing and Flow Control in Computer Communication Networks)

  • 이광재;김정선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.928-932
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    • 1987
  • Successful operation of a computer network Is dependent on the adequate routing and flow control. Routing and flow control algorithms are studied together rather than as isolated mechanism. In this paper, we discuss the effect of the flow control and routing algorithms.

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컴퓨터 하드 디스크의 정밀 서보 제어 (Precision servo control of a computer hard disk)

  • 전도영
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.286-289
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    • 1996
  • Two servo control algorithms are suggested to reduce the tracking error of a computer hard disk drive. One is the repetitive control to reduce the repeatable tracking error which is not explicitly taken into account in the design of a conventional controller. This algorithm was successfully applied to a commercial disk using a fixed point DSP. The other is the multi-rate sampling control which generates the control output between each sampling times since the sampling time of hard disk drives is limited. These algorithms were shown effectively to reduce tracking errors.

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AN OPTIMAL ALGORITHM FOR FINDING DETH-FIRST SPANNING TREE ON PERMUTATION GRAPHS

  • Mondal, Sukumar;Pal, Madhumangal;Pal, Tapan K.
    • Journal of applied mathematics & informatics
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    • 제6권3호
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    • pp.727-734
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    • 1999
  • Let G be a connected graph of n vertices. The problem of finding a depth-first spanning tree of G is to find a connected subgraph of G with the n vertices and n-1 edges by depth-first-search. in this paper we propose an O(n) time algorithm to solve this problem on permutation graphs.

WHAT CAN WE SAY ABOUT THE TIME COMPLEXITY OF ALGORITHMS \ulcorner

  • Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • 제8권3호
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    • pp.959-973
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    • 2001
  • We shall discuss one of some techniques needed to analyze algorithms. It is called a big-O function technique. The measures of efficiency of an algorithm have two cases. One is the time used by a computer to solve the problem using this algorithm when the input values are of a specified size. The other one is the amount of computer memory required to implement the algorithm when the input values are of a specified size. Mainly, we will restrict our attention to time complexity. To figure out the Time Complexity in nonlinear problems of Numerical Analysis seems to be almost impossible.

잡음 환경에서의 음성 검출 알고리즘 비교 연구 (A Comparative Study of Voice Activity Detection Algorithms in Adverse Environments)

  • 양경철;육동석
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2006년도 춘계 학술대회 발표논문집
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    • pp.45-48
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    • 2006
  • As the speech recognition systems are used in many emerging applications, robust performance of speech recognition systems under extremely noisy conditions become more important. The voice activity detection (VAD) has been taken into account as one of the important factors for robust speech recognition. In this paper, we investigate conventional VAD algorithms and analyze the weak and the strong points of each algorithm.

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