• Title, Summary, Keyword: heuristic rule

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A study on sequencing of Mixed Model Assembly Line for increasing productivity (혼합모델조립라인의 생산성 제고를 위한 작업순서 결정)

  • 최종열
    • Korean Management Science Review
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    • v.13 no.2
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    • pp.25-48
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    • 1996
  • Mixed Model Assembly Lines (MMALs) are increasingly used to produce differentiated products on a single assembly line without work-in-process storage, Usually, a typical MMAL consists of a number of (1) stations doing exactly the same operation on every job, (2) stations involving operations with different choices, and (3) stations offering operations that are not performed on every job, or that are performed on every job but with many options. For stations of the first type there is no sequencing problem at all. However, for the second type a set-up cost is incurred each time the operation switches from one choice to another. At the third type of stations, different models, requring different amounts and choices of assembly work, creates an uneven flow of work along the line and variations in the work load at these stations. When a subsequence of jobs requires more work load than the station can handle, it is necessary to help the operations at the station or to complete the work elsewhere. Therefore, a schedule which minimize the sum of set-up cost and utility work cost is desired. So this study has developed Fixed Random Ordering Rule (FROR), Fixed Ascending Ordering Rule (FAOR), Fixed Descending Ordering Rule, and Extended NHR (ENHR). ENHR is to choose optimal color ordering of each batch with NHR, and to decide job sequence of the batch with it, too. As the result of experiments, ENHR was the best heuristic algorithm. NHR is a new heuristic rule in which only the minimum addition of violations from both partial sequence and unassigned sequence at every branch could be considered. And this is a heuristic sequencing rule for the third type of stations at MMAL. This study developed one more heuristic algorithm to test the performance of NHR, which is named as Practical Heuristic Rule (PHR).

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A Study on Project Scheduling under Multiple Resource Constraints (다수 자원제약 하에서의 프로젝트 일정계획에 관한 연구)

  • Lee, Jeong-Hun;Kim, Pan-Sool;Moon, Il-Kyeong
    • Journal of Korean Institute of Industrial Engineers
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    • v.36 no.4
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    • pp.219-229
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    • 2010
  • The PERT/CPM are considered as the base procedures for the most successful project scheduling programs. Unfortunately, it is not easy to apply these procedures to real-life projects. This is due to the fact that PERT/CPM assume an infinite number of resources for each activity in project networks. Obviously, the completion time under no constraints is less than when constraints are imposed. One way of approaching this problem is to use heuristic solution techniques. In this paper, we present three heuristics; MRU (Maximum Resource Use) rule, STU (Shortest Time Use) rule, MRUP (Max Resource Use and Period) rule for allocating resources to activities of projects under multiple resource constraints. Comparisons of the project durations show that these heuristic rules are superior to AG3 rule that has been widely used in practice (Elsayed and Boucher, 1994).

Selection of scheduling heuristics using neural network and MCDM (신경망과 다속성 의사결정 기법을 이용한 일정관리 휴리스틱의 선택)

  • 황인수;한재민
    • Korean Management Science Review
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    • v.13 no.3
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    • pp.173-186
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    • 1996
  • This paper presents an approach for classifying scheduling problems and selecting a heuristic rule to yield best solution in terms of certain performance measure(s). Classification parameters are employed from previous studies on job shop scheduling and project scheduling. Neural network is used for learning and estimating the performance of heuristic rules. In addition, multi-criteria decision making techniques are employed to combine the preferences for each performance measure and heuristic rule for the problems with multi-objectives.

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A Heuristic Rule for the Performance Improvement in Time Domain Passivity Control of Haptic Interfaces

  • Kim, Yoon-Sang;Blake Hannaford
    • Transactions on Control, Automation and Systems Engineering
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    • v.4 no.3
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    • pp.212-216
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    • 2002
  • A practical issue is studied to improve the performance of a new energy based method of achieving stable, high performance haptic interface control. The issue is related to resetting the amount of energy accumulated in the Passivity Observer for faster operation. A heuristic method is derived and experimentally tested for the resetting and it is shown to help the PC to operate sooner when the system gets active. Experimental results are presented for the “Excalibur” haptic device.

Production Planning Method Using the Push-back Heuristic Algorithm: Implementation in a Micro Filter Manufacturer in South Korea

  • Sung, Shin Woong;Jang, Young Jae;Lee, Sung Wook
    • Industrial Engineering and Management Systems
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    • v.14 no.4
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    • pp.401-412
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    • 2015
  • In this paper, we present a modeling approach to production planning for an actual production line and a heuristic method. We also illustrate the successful implementation of the proposed method on the production line. A heuristic algorithm called the push-back algorithm was designed for a single machine earliness/tardiness production planning with distinct due date. It was developed by combining a minimum slack time rule and shortest processing time rule with a push-back procedure. The results of a numerical experiment on the heuristic's performance are presented in comparison with the results of IBM ILOG CPLEX. The proposed algorithm was applied to an actual case of production planning at Woongjin Chemical, a leading manufacturer of filter products in South Korea. The seven-month execution of our algorithm led to a 24.5% decrease in the company's inventory level, thus demonstrating its practicality and effectiveness.

A Heuristic Method for Assembly Line Balancing of Large-Sized Product (대형제품의 조립라인 밸런싱을 위한 Heuristic 기법)

  • Kim, Y.G.;Kwon, S.H.;Cho, M.R.
    • Journal of Korean Institute of Industrial Engineers
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    • v.17 no.2
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    • pp.51-61
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    • 1991
  • This paper presents a heuristic method for the Assembly Line Balancing(ALB) of the large-sized product. In the ALB problem of the large-sized product such as bus and truck, the assignments of the Related Task Groups(RTG), the same side tasks, and team tasks should be considered. In this paper, a new concept of the RTG and two kinds of assignment rules are proposed to resolve the above considerations. The first assignment rule allots the RTG with the constraint of the same side tasks to the station while the second allots the RTG to the station, relaxing the above constraint to increase the applicability of the method. An assignment rule for team tasks is also presented. The benefits of the method are to improve work methods, to give more job satisfaction to workers, and to allow greater flexibility in the design of assembly lines.

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Weighted Fuzzy Reasoning Using Certainty Factors as Heuristic Information in Weighted Fuzzy Petri Net Representations (가중 퍼지 페트리네트 표현에서 경험정보로 확신도를 이용하는 가중 퍼지추론)

  • Lee, Moo-Eun;Lee, Dong-Eun;Cho, Sang-Yeop
    • Journal of Information Technology Applications and Management
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    • v.12 no.4
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    • pp.1-12
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    • 2005
  • In general, other conventional researches propose the fuzzy Petri net-based fuzzy reasoning algorithms based on the exhaustive search algorithms. If it can allow the certainty factors representing in the fuzzy production rules to use as the heuristic information, then it can allow the reasoning of rule-based systems to perform fuzzy reasoning in more effective manner. This paper presents a fuzzy Petri net(FPN) model to represent the fuzzy production rules of a rule-based system. Based on the fuzzy Petri net model, a weighted fuzzy reasoning algorithm is proposed to Perform the fuzzy reasoning automatically, This algorithm is more effective and more intelligent reasoning than other reasoning methods because it can perform fuzzy reasoning using the certainty factors which are provided by domain experts as heuristic information

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A Modified Heuristic Algorithm for the Mixed Model Assembly Line Balancing

  • Lee, Sung-Youl
    • Journal of the Korea Industrial Information Systems Research
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    • v.15 no.3
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    • pp.59-65
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    • 2010
  • This paper proposes a modified heuristic mixed model assembly line (MMAL) balancing algorithm that provides consistent station assignments on a model by model basis as well as on a station by station. Basically, some of single model line balancing techniques are modified and incorporated to be fit into the MMAL. The proposed algorithm is based on N.T. Thomopoulos' [8] method and supplemented with several well proven single model line balancing techniques proposed in the literature until recently. Hoffman's precedence matrix [2] is used to indicate the ordering relations among tasks. Arcus' Rule IX [1] is applied to generate rapidly a fairly large number of feasible solutions. Consequently, this proposed algorithm reduces the fluctuations in operation times among the models as well as the stations and the balance delays. A numerical example shows that the proposed algorithm can provide a good feasible solution in a relatively short time and generate relatively better solutions comparing to other three existing methods.

An Optimization Rule for Channel Assignment Problem (CAP) (통신채널 할당 최적화 규칙)

  • Lee, Sang-Un
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.6
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    • pp.37-45
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    • 2013
  • In the absence of a single deterministic rule for the channel assignment problems, heuristic algorithms are predominantly employed to partly solve the problems. This paper thus proposes deterministic rules for the channel assignment problems. These deterministic rules have successfully yielded the optimal solution when applied to the Philadelphia's 9 case examples.