• Title/Summary/Keyword: branch-bound

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A study on the column subtraction method applied to ship scheduling problem

  • Hwang, Hee-Su;Lee, Hee-Yong;Kim, Si-Hwa
    • Journal of Navigation and Port Research
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    • v.28 no.2
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    • pp.129-133
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    • 2004
  • Column subtraction, originally proposed by Harche and Thompson(1994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation This paper aim, at applying the column subtraction method to solve SSP which am not be solved by LP relaxation For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch and-bound algorithm by LINDO.

A Study on Minimum Cost Expansion Planning of Power System by Branch and Bound Method (분지한정법에 의한 전력계통의 최소비용에 관한 연구)

  • 송길영;최재석
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.33 no.1
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    • pp.9-16
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    • 1984
  • This paper describes the minimum cost expansion planning which is based on the economical aspect under the various conditions on the power system expansion planning. It presents not only linear cost characteristics analysis but also stepwise cost characteristics analysis which satisfies practical condition in the power system. The latter analysis must be handled by integer programming (IP), because the relation between the cost and the capacity has stepwise characteristics. In order to proceed the latter analysis, the solving procedure is illustrated in detais by using branch and bound method which includes the network flow theory and maximum flow-minimum cut theorem.

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Scheduling for a Two-Machine, M-Parallel Flow Shop to Minimize Makesan

  • Lee, Dong Hoon;Lee, Byung Gun;Joo, Cheol Min;Lee, Woon Sik
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.56
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    • pp.9-18
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    • 2000
  • This paper considers the problem of two-machine, M-parallel flow shop scheduling to minimize makespan, and proposes a series of heuristic algorithms and a branch and bound algorithm. Two processing times of each job at two machines on each line are identical on any line. Since each flow-shop line consists of two machines, Johnson's sequence is optimal for each flow-shop line. Heuristic algorithms are developed in this paper by combining a "list scheduling" method and a "local search with global evaluation" method. Numerical experiments show that the proposed heuristics can efficiently give optimal or near-optimal schedules with high accuracy. with high accuracy.

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Assignment-Change Optimization for the Problem of Bid Evaluation (입찰 평가 문제의 배정-변경 최적화)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.21 no.4
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    • pp.171-176
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    • 2021
  • This paper deals with bid evaluation problem that chooses the vendors and quantity with minimum purchasing cost for bid information of setup cost and unit price. For this problem, the branch-and-bound(BB) and branch-and-cut(BC) methods are well-known. But these methods can be fail to obtain the optimal solution. This paper gets the initial feasible solution with procuring quantity assignment principle in accordance with the unit price or setup cost rank-first. Then procuring quantity moving optimization(vendor change) is execute take account of unit price or setup cost rank. As a result of experimentation, the propose algorithm is significantly lower compared to BB and BC.

Efficient Reverse Skyline Processing using Branch-and-Bound (분기한정법을 이용한 효율적인 리버스 스카이라인 질의 처리)

  • Han, Ah;Park, Young-Bae
    • Journal of KIISE:Databases
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    • v.37 no.1
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    • pp.12-21
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    • 2010
  • Recently, "Service of information perspective" that is an important issue is that a company searches customers that interested in certain information and the company offers information to the customers. This service can gain high effects by low cost because of supporting selective information. In most recently, Reverse Skyline using Skyline Approximation(RSSA) is proposed to process services of information provider's perspective. RSSA has problem to defects about waste of processing time and memory. In this paper, Efficient Reverse Skyline(ERSL) Algorithm is proposed for Efficient processing the Skyline. ERSL is new Algorithm using Branch and Bound Skyline(BBS) reduces the waste of processing time and memory. When we execute the variety experimentation to valuation ERSL algorithm's capacity. It is proved the best efficient algorithm among the others because ERSL is flexibly kept the established capacity.

Design of FIR Filters with Finite Precision Coefficients Using LP(Linear Programming) (선형계획을 이용한 유도 정밀도 계수 FIR 필터의 설계)

  • 조남익;이상욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2386-2396
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    • 1994
  • In this paper, an optimal algorithm for the design of 1-D FIR filters with finite precision coefficients is proposed. The algorithm is based on the observation that the frequency constraints of a sub-problems(SP) in the branch and bound algorithm, which repeatedly use LP(linear programming), are closely related with those of neighboring SPs. By using the relationship between the SPs, the proposed algorithm reduces the number of constraints required for solving each SP with Lp, whereas the conventional algorithm employs all the constraints, which are required for solving the initial problem. Thus, the overall computational load for the design of FIR filters with finite precision coefficients is significantly alleviated, compared to the conventional branch and bound algorithm. Also, a new branching scheme for the design of FIR filters with sum-of-power-of-two(SOPOT) coefficients is proposed. It is shown that the computational load for the design fo SOPT coefficient filters can be further reduced with the new branching scheme.

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Integer Programming-based Maximum Likelihood Method for OFDM Parameter Estimation

  • Chitpinityon, Nudcharee;Chotikakamth, Nopporn
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1780-1783
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    • 2002
  • A problem of signal transmitted and received in OFDM systems is considered. In particular, an efficient solution to the problem of blind channel estimation based on Maximum Likelihood (ML) principle has been investigated. The paper proposes a new upper-bound cost, used in conjunction with a standard branch and bound integer programming technique for solving the ML problem. The tighter upper-bound cost exploits a finite-alphabet property of the transmitted signal. The proposed upper-bound cost was found to greatly speed up the ML algorithm, thus reducing computational complexity. Experimental results and discussion are included.

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A Non-Uniform Convergence Tolerance Scheme for Enhancing the Branch-and-Bound Method (비균일 수렴허용오차 방법을 이용한 분지한계법 개선에 관한 연구)

  • Jung, Sang-Jin;Chen, Xi;Choi, Gyung-Hyun;Choi, Dong-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.36 no.4
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    • pp.361-371
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    • 2012
  • In order to improve the efficiency of the branch-and-bound method for mixed-discrete nonlinear programming, a nonuniform convergence tolerance scheme is proposed for the continuous subproblem optimizations. The suggested scheme assigns the convergence tolerances for each continuous subproblem optimization according to the maximum constraint violation obtained from the first iteration of each subproblem optimization in order to reduce the total number of function evaluations needed to reach the discrete optimal solution. The proposed tolerance scheme is integrated with five branching order options. The comparative performance test results using the ten combinations of the five branching orders and two convergence tolerance schemes show that the suggested non-uniform convergence tolerance scheme is obviously superior to the uniform one. The results also show that the branching order option using the minimum clearance difference method performed best among the five branching order options. Therefore, we recommend using the "minimum clearance difference method" for branching and the "non-uniform convergence tolerance scheme" for solving discrete optimization problems.

Redundancy Optimization under Multiple Constraints (다제약식하에서의 최적중복설계에 관한 연구)

  • Yun Deok-Gyun
    • Journal of the military operations research society of Korea
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    • v.11 no.2
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    • pp.53-63
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    • 1985
  • This paper presents a multi-costraint optimization model for redundant system reliability. The optimization model is usually formulated as a nonlinear integer programming (NIP) problem. This paper reformulates the NIP problem into a linear integer programming (LIP) problem. Then an efficient 'Branch and Straddle' algorithm is proposed to solve the LIP problem. The efficiency of this algorithm stems from the simultaneous handling of multiple variables, unlike in ordinary branch and bound algorithms. A numerical example is given to illustrate this algorithm.

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