• 제목/요약/키워드: algorithms

검색결과 16,281건 처리시간 0.044초

분산 유전알고리즘의 TSP 적용 (Distributed Genetic Algorithms for the TSP)

  • 박유석
    • 대한안전경영과학회지
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    • 제3권3호
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    • pp.191-200
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    • 2001
  • Parallel Genetic Algorithms partition the whole population into several sub-populations and search the optimal solution by exchanging the information each others periodically. Distributed Genetic Algorithm, one of Parallel Genetic Algorithms, divides a large population into several sub-populations and executes the traditional Genetic Algorithm on each sub-population independently. And periodically promising individuals selected from sub-populations are migrated by following the migration interval and migration rate to different sub-populations. In this paper, for the Travelling Salesman Problems, we analyze and compare with Distributed Genetic Algorithms using different Genetic Algorithms and using same Genetic Algorithms on each separated sub-population The simulation result shows that using different Genetic Algorithms obtains better results than using same Genetic Algorithms in Distributed Genetic Algorithms. This results look like the property of rapidly searching the approximated optima and keeping the variety of solution make interaction in different Genetic Algorithms.

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General Algorithms for Construction of Broadcast and Multicast Trees with Applications to Wireless Networks

  • Nguyen Gam D.
    • Journal of Communications and Networks
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    • 제7권3호
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    • pp.263-277
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    • 2005
  • In this paper, we introduce algorithms for constructing broadcasting and multicasting trees. These algorithms are general because they may be used for tree cost functions that are of arbitrary form. Thus, essentially the same algorithmic procedures are used for different tree cost functions. We evaluate the effectiveness of the general algorithms by applying them to different cost functions that are often used to model wired and wireless net­works. Besides providing a unifying framework for dealing with many present and future tree-construction applications, these algorithms typically outperform some existing algorithms that are specifically designed for energy-aware wireless networks. These general algorithms perform well at the expense of higher computational complexity. They are centralized algorithms, requiring the full network information for tree construction. Thus, we also present variations of these general algorithms to yield other algorithms that have lower complexity and distributed implementation.

Performance Analysis of a Combination of Carry-in and Remarshalling Algorithms

  • PARK, Young-Kyu;UM, Kyung-Ho
    • 산경연구논집
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    • 제11권10호
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    • pp.75-89
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    • 2020
  • Purpose: The container terminal is an area that plays an important role in the country's import and export. As the volume of containers increased worldwide, competition between terminals became fiercer, and increasing the productivity of terminals became more important. Re-handling is a serious obstacle that lowers the productivity of terminal. There are two ways to reduce re-handling in the terminal yard. The first method is to load containers in terminal yards using effective carry-in algorithms that reduce re-handling. The second method is to carry out effective remarshalling. In this paper, the performance of various carry-in algorithms and various remarshalling algorithms are reviewed. Next, we try to find the most effective combination of carry-in algorithm and remarshalling algorithm. Research design, data and methodology: In this paper, we analyze the performance of the four carry-in algorithms, AP, MDF, LVF, RP and the four remarshalling algorithms, ASI, ASI+, ASO, ASO+. And after making all the combinations of carry-in algorithms and remarshalling algorithms, we compare their performance to find the best combination. To that end, many experiments are conducted with eight types of 100 bays through simulation. Results: The results of experiments showed that AP was effective among the carry-in algorithms and ASO+ was effective among remarshalling algorithms. In the case of the LVF algorithm, the effect of carrying in was bad, but it was found to be effective in finding remarshalling solution. And we could see that ASI+ and ASO+, algorithms that carry out remarshalling even if they fail to find remarshalling solution, are also more effective than ASI and ASO. And among the combinations of carry-in algorithms and remarshalling algorithms, we could see that the combination of AP algorithm and ASO+ algorithm was the most effective combination. Conclusion: We compared the performance of the carry-in algorithms and the remarshalling algorithms and the performance of their combination. Since the performance of the container yard has a significant effect on the performance of the entire container terminal, it is believed that the results of this experiment will be effective in improving the performance of the container terminal when carrying-in or when remarshalling.

SEQUENTIAL AND PARALLEL ALGORITHMS FOR MINIMUM FLOWS

  • Ciurea, Eleonor;Ciupala, Laura
    • Journal of applied mathematics & informatics
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    • 제15권1_2호
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    • pp.53-75
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    • 2004
  • First, we present two classes of sequential algorithms for minimum flow problem: decreasing path algorithms and preflow algorithms. Then we describe another approach of the minimum flow problem, that consists of applying any maximum flow algorithm in a modified network. In section 5 we present several parallel preflow algorithms that solve the minimum flow problem. Finally, we present an application of the minimum flow problem.

QR 분해법을 이용한 적응 쌍선형 격자 알고리듬 (QR-Decomposition based Adaptive Bbilinear Lattice Algorithms)

  • 안봉만;황지원;백흥기
    • 전자공학회논문지B
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    • 제31B권10호
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    • pp.32-43
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    • 1994
  • This paper presents new QRD-based recursive least squares algorithms for bilinear lattice filter. Bilinear recursive least square lattice algorithms are derived by using the QR decomposition for minimization covariance matrix of predication error by applying Givens rotation to the bilinear recursive least squares lattics algorithms. The proposed algorithms are applied to the bilinear system identification to evaluate the performance of algoithms. Computer simulations show that the convergence properties of the proposed algorithms are superior to that of the algorithms proposed by Baik when signal includes the measurement noise.

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Discrete Optimum Design of Space Truss Structures Using Genetic Algorithms

  • Park, Choon Wook;Kang, Moon Myung
    • Architectural research
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    • 제4권1호
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    • pp.33-38
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    • 2002
  • The objective of this study is the development of discrete optimum design algorithms which is based on the genetic algorithms. The developed algorithms was implemented in a computer program. For the optimum design, the objective function is the weight of space trusses structures and the constraints are stresses and displacements. This study solves the problem by introducing the genetic algorithms. The genetic algorithms consists of genetic process and evolutionary process. The genetic process selects the next design points based on the survivability of the current design points. The evolutionary process evaluates the survivability of the design points selected from the genetic process. The efficiency and validity of the developed discrete optimum design algorithms was verified by applying the algorithms to optimum design examples.

공유된 멀티캐스트 트리에서 센터 위치 결정을 위한 새 알고리즘 (New conter location algorithms for shared multicast trees)

  • 강신규;심영철
    • 한국통신학회논문지
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    • 제25권3B호
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    • pp.493-503
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    • 2000
  • Multicast routing algorithms such PIM, CBT, BGMP use shared multicast routing trees and the location of the multicast tree has great impact on the packet delay. In this pater we propose three new center location algorithms and analyze their performance through simulation studies. these three algorithms consider as candidates for the center not only multicast group members but also a few non-members nodes. To select these non-member nodes, we first find all the shortest paths among every couple of members and consider either nodes which are most frequently visited during the process of finding shortest paths or nodes which lie at the center of a shortest path and are most frequently visited during the same process. There the proposed algorithms are able to find the better center than not only algorithms which consider only member nodes but also other algorithms which consider selected non-member nodes in addition ot member nodes. The proposed algorithms either incur too much overhead nor depend upon unicasting algorithms.

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Toward a New Safer Cybersecurity Posture using RC6 & RSA as Hybrid Crypto-Algorithms with VC Cipher

  • Jenan.S, Alkhonaini;Shuruq.A, Alduraywish;Maria Altaib, Badawi
    • International Journal of Computer Science & Network Security
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    • 제23권1호
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    • pp.164-168
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    • 2023
  • As our community has become increasingly dependent on technology, security has become a bigger concern, which makes it more important and challenging than ever. security can be enhanced with encryption as described in this paper by combining RC6 symmetric cryptographic algorithms with RSA asymmetric algorithms, as well as the Vigenère cipher, to help manage weaknesses of RC6 algorithms by utilizing the speed, security, and effectiveness of asymmetric algorithms with the effectiveness of symmetric algorithm items as well as introducing classical algorithms, which add additional confusion to the decryption process. An analysis of the proposed encryption speed and throughput has been conducted in comparison to a variety of well-known algorithms to demonstrate the effectiveness of each algorithm.

K-Shortest Path 알고리즘에 기초한 새로운 대역폭 보장 라우팅 알고리즘 (New Bandwidth Guaranteed Routing Algorithms based on K-Shortest Path Algorithm)

  • 이준호;이성호
    • 한국통신학회논문지
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    • 제28권11B호
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    • pp.972-984
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    • 2003
  • 본 논문에서는 MPLS 네트워크에서 LSP 설정에 적용될 수 있는 새로운 대역폭 보장 온라인 라우팅 알고리즘들을 제안하고 기존의 알고리즘들과 함께 그 성능을 시뮬레이션을 통해서 평가한다. 제안된 방식은 기존의 WSP나 SWP 알고리즘을 K-shortest loopless path 알고리즘에 기초해서 확장시킨 형태를 가진다. 시뮬레이션을 통해서 accepted bandwidth, accepted request number 그리고 average path length라는 성능을 평가한 결과, 모든 노드들이 LSP 설정의 ingress나 egress 노드가 될 수 있는 상황에서 제안된 방식들이 전반적으로 우수한 성능을 보였는데 네트워크 부하가 큰 경우에는 특히, 최소 홉 경로에 기초한 방식들이 좋은 성능을 보임을 알 수 있다.

A Computationally Efficient Optimal Allocation Algorithms for Large Data

  • Kwon, Il-Hyung;Kim, Ju-Sung
    • Journal of the Korean Data and Information Science Society
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    • 제18권2호
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    • pp.561-572
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    • 2007
  • In this paper, we describe various efficient optimization algorithms for obtaining an optimal customer allocation in the telephone call center. The main advantages of the proposed algorithms are simple, fast and very attractive for massive dataset. The proposed algorithms also provide comparable performance with the other more sophisticated linear programming methods. The proposed optimal allocation algorithms increase the customer contact, response rate and management product and optimize the performance of call centers. Simulation results are given to demonstrate the effectiveness of our algorithms.

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