• Title/Summary/Keyword: Branch-and-Bound Algorithm

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A Study for Scheduling Jobs on Unrelated Parallel Processors

  • Kang, Suk-Ho;Park, Sung-Soo
    • Journal of the military operations research society of Korea
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    • v.9 no.1
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    • pp.51-61
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    • 1983
  • Lagrangian relaxation is used to the problem of scheduling jobs on unrelated parallel processors with the objective of minimizing makespan. The implicit condition for optimality is drawn out explicitly in order to apply the subgradient algorithm. To obtain the optimal solution, branch-and-bound-search method is devised. In the search, the special structure of the problem is exploited effectively, Some computational experiences with the algorithm are presented, and comparisons are made with the Land and Doig method.

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A Study on the Improvement of Multitree Pattern Recognition Algorithm (Multitree 형상 인식 기법의 성능 개선에 관한 연구)

  • 김태성;이정희;김성대
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.14 no.4
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    • pp.348-359
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    • 1989
  • The multitree pattern recognition algorithm proposed by [1] and [2] is modified in order to improve its performance. The basic idea of the multitree pattern classification algorithm is that the binary dceision tree used to classify an unknow pattern is constructed for each feature and that at each stage, classification rule decides whether to classify the unknown pattern or to extract the feature value according to the feature ordet. So the feature ordering needed in the calssification procedure is simple and the number of features used in the classification procedure is small compared with other classification algorithms. Thus the algorithm can be easily applied to real pattern recognition problems even when the number of features and that of the classes are very large. In this paper, the wighting factor assignment scheme in the decision procedure is modified and various classification rules are proposed by means of the weighting factor. And the branch and bound method is applied to feature subset selection and feature ordering. Several experimental results show that the performance of the multitree pattern classification algorithm is improved by the proposed scheme.

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Efficient Handwritten Character Verification Using an Improved Dynamic Time Warping Algorithm (개선된 동적 타임 워핑 알고리즘을 이용한 효율적인 필기문자 감정)

  • Jang, Seok-Woo;Park, Young-Jae;Kim, Gye-Young
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.7
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    • pp.19-26
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    • 2010
  • In this paper, we suggest a efficient handwritten character verification method in on-line environments which automatically analyses two input character string and computes their similarity degrees. The proposed algorithm first applies the circular projection method to input handwritten strings and extracts their representative features including shape, directions, etc. It then calculates the similarity between two character strings by using an improved dynamic time warping (DTW) algorithm. We improved the conventional DTW algorithm efficiently through adopting the branch-and-bound policy to the existing DTW algorithm which is well-known to produce good results in the various optimization problems. The experimental results to verify the performance of the proposed system show that the suggested handwritten character verification method operates more efficiently than the existing DTW and DDTW algorithms in terms of the speed.

Branch-and-Bound Algorithm for Division of Perfect Nine Dart Combinations (퍼펙트 9 다트 조합의 나눗셈 분기한정 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.4
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    • pp.87-94
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    • 2022
  • This paper researched a study to find a combination of acquisition scores for 9 dart throws, which is the minimum number of dart tactile throws in 501 point dart games. The maximum score that can be obtained by throwing once in a dart game is 60 points, which can end the perfect dart game with 60 points eight times according to 60×8+21×1=501, and if you earn 21 points once, you can finish the game with 9 throws. This is called 9-dart finish. As such, only 18 and 14 studies on the combination of scores that can obtain 501 points with 9 throws are known, and no studies have been conducted applying the exhaustive search algorithm. This paper proposed a division branch-and-bound algorithm as a method of simplifying the O(2n) exponential time performance complexity of the typical branch-and-bound method of a exhaustive search method, to polynomial time complexity. The proposed method limited the level to 8, jumped to a quotient level of 501/60, and backtracked to explore only possible score combinations in the previous level. The possible score combinations of the nine perfect games found with the proposed algorithm were 90(101 cases).

Exploring Efficient Solutions for the 0/1 Knapsack Problem

  • Dalal M. Althawadi;Sara Aldossary;Aryam Alnemari;Malak Alghamdi;Fatema Alqahtani;Atta-ur Rahman;Aghiad Bakry;Sghaier Chabani
    • International Journal of Computer Science & Network Security
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    • v.24 no.2
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    • pp.15-24
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    • 2024
  • One of the most significant issues in combinatorial optimization is the classical NP-complete conundrum known as the 0/1 Knapsack Problem. This study delves deeply into the investigation of practical solutions, emphasizing two classic algorithmic paradigms, brute force, and dynamic programming, along with the metaheuristic and nature-inspired family algorithm known as the Genetic Algorithm (GA). The research begins with a thorough analysis of the dynamic programming technique, utilizing its ability to handle overlapping subproblems and an ideal substructure. We evaluate the benefits of dynamic programming in the context of the 0/1 Knapsack Problem by carefully dissecting its nuances in contrast to GA. Simultaneously, the study examines the brute force algorithm, a simple yet comprehensive method compared to Branch & Bound. This strategy entails investigating every potential combination, offering a starting point for comparison with more advanced techniques. The paper explores the computational complexity of the brute force approach, highlighting its limitations and usefulness in resolving the 0/1 Knapsack Problem in contrast to the set above of algorithms.

A Branch-and-price Algorithm for the Minimum ADM Problem on WDM Ring Networks (WDM 링에서의 ADM 최소화 문제에 대한 분지평가 해법)

  • Chung, Ji-Bok
    • Journal of the Korean Operations Research and Management Science Society
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    • v.32 no.4
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    • pp.51-60
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    • 2007
  • In this study, we consider the minimum ADM problem which is the fundamental problem for the cost-effective design of SONET ADM embedded in WDM ring networks. To minimize the number of SONET ADMs, efficient algorithms for the routing and wavelength assignment are needed. We propose a mathematical model based on the graph theory for the problem and propose a branch-and-price approach to solve the suggested model effectively within reasonable time. By exploiting the mathematical structure of ring networks, we developed polynomial time algorithms for column generation subroutine at branch-and-bound tree. In a computer simulation study, the suggested approach can find the optimal solution for sufficient size networks and shows better performance than the greedy heuristic method.

A Load Balanced Clustering Model for Energy Efficient Packet Transmission in Wireless Sensor Networks (무선 센서 네트워크에서 에너지 효율적 패킷 전송을 위한 부하 균형 클러스터링 모델)

  • Lee, Jae-Hee;Kim, Byung-Ki;Kang, Seong-Ho
    • KIPS Transactions on Computer and Communication Systems
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    • v.4 no.12
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    • pp.409-414
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    • 2015
  • The energy conservation is the most important subject for long run operation of the sensor nodes with limited power resources. Clustering is one of most energy efficient technique to grouped the sensor nodes into distinct cluster. But, in a cluster based WSN, CHs and gateways bear an extra work load to send the processed data to the sink. The inappropriate cluster formation may cause gateways overloaded and may increase latency in communication. In this paper, we propose a novel load balanced clustering model for improving energy efficiency and giving a guarantee of long network lifetime. We show the result of performance measurement experiments that designs using a branch and bound algorithm and a multi-start local search algorithm to compare with the existing load balanced clustering model.

Low Power Force-Directed scheduling for Optimal module selection Architecture Synthesis (최적 모듈 선택 아키텍쳐 합성을 위한 전력 감소 Force-Directed 스케쥴링)

  • Choi, Ji-Young;Kim, Hi-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.9A
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    • pp.1091-1100
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    • 2004
  • In this paper, we present a reducing power conswnption of a scheduling for module selection under the time constraint. The proposed low power scheduling executes FDS_LP considering low power to exist the FDS scheduling by inputted the behavioral language. The proposed FDS_LP perfonns lower power consumption with dynamic power which is minimized the switching activity, based on force conception In the time step of module selection, an optimal RT(Register Transfer) library is composed by exploration of the parameters such as power, area, and delay. To find optimal parameters of RT library, an optimal module selection algorithm using Branch and Bound algorithm is also proposed. In the comparison and experimental results, The proposed FDS_LP algorithm reduce maximum power saving up to 23.9% comparing to previous FDS algorithm.

A Study on Development of Maintenance Cost Estimation System for BTL Project of Education Facilities Using Optimization Methodology (최적화기법을 활용한 교육시설물 BTL 사업 운영관리비용 비용예측 시스템 개발 기초연구)

  • Cho, Chang-Yeon;Son, Jae-Ho;Kim, Jea-On
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.1
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    • pp.45-57
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    • 2009
  • BTL (Build-Transfer-Lease) Project for Education Facilities are contracted as a package which consists of several education facilities. The general maintenance period of BTL project for education facilities is 20 years. Thus, total cost variation largely depends on the accuracy of the maintenance cost forecasting in the early stage in the life cycle of the BTL Project. This research develops a cost forecasting system using complete linkage algorithm and branch & bound algorithm to help in finding optimal bundling combination. This system helps owner's decision-making to estimate the total project cost with various constraints changing. The result of this research suggests more reasonable and effective forecasting model for the maintenance facilities package in the BTL project.

Optimi Design for R.C. Beam with Discrete Variables (이산형 설계변수를 갖는 철그콘크리트보의 최적설계)

  • 구봉근;한상훈;김홍룡
    • Magazine of the Korea Concrete Institute
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    • v.5 no.4
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    • pp.167-178
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    • 1993
  • The objective of this paper is to look into the possibility of the detailed and practical optimum design of rt:inforced concrete beam using methods oi discrete mathematical programming. In this discrete optimum formulation, the design variables are the overall depth, width and effective depth of members, and area of longitudinal reinforcement. In addition, the details such as the amount of web reinforcement and cutoff points of longitudinal reinforcement are also considered as variables. Total cost has been used as the objective function. The constraints include the code requirments such as flexural strength, shear strength, ductility, serviceability, concrete cover. spacing, web reinforcement, and development length and cutoff points of longitudinal renforcement. An optimization algorithm is presented for effective optimum design of R.C. beam with discrete de sign variables. First, the continuous variable optimization can be achieved by Feasible Direction Method. Using the results obtained from the continuous variable optimization, a branch and bound method is used to obtained the discrete design values. The proposed algorithm is applied to test problem for reliability, and the results are compared with those of graphical method and rounded-up method. And a simply supported R.C. beam and a two-span continuous R.C. beam are presented as numerical examples for effectiveness and applicability. It is considered that the presented algorithm can be effectively applied to the discrete optimum design of R.C. beams.