• Title/Summary/Keyword: scheduling

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A Genetic Algorithm for Dynamic Job Shop Scheduling (동적 Job Shop 일정계획을 위한 유전 알고리즘)

  • 박병주;최형림;김현수;이상완
    • Journal of the Korean Operations Research and Management Science Society
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    • v.27 no.2
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    • pp.97-109
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    • 2002
  • Manufacturing environments in the real world are subject to many sources of change and uncertainty, such as new job releases, job cancellations, a chance in the processing time or start time of some operation. Thus, the realistic scheduling method should Properly reflect these dynamic environment. Based on the release times of jobs, JSSP (Job Shoe Scheduling Problem) can be classified as static and dynamic scheduling problem. In this research, we mainly consider the dynamic JSSP with continually arriving jobs. The goal of this research is to develop an efficient scheduling method based on GA (Genetic Algorithm) to address dynamic JSSP. we designed scheduling method based on SGA (Sing1e Genetic Algorithm) and PGA (Parallel Genetic Algorithm) The scheduling method based on GA is extended to address dynamic JSSP. Then, This algorithms are tested for scheduling and rescheduling in dynamic JSSP. The results is compared with dispatching rule. In comparison to dispatching rule, the GA approach produces better scheduling performance.

A PROACTIVE APPROACH FOR RESOURCE CONSTRAINED SCHEDULING OF MULTIPLE PROJECTS

  • Balasubramanian Kanagasabapathi;Kuppusamy Ananthanarayanan
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.744-747
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    • 2005
  • The AEC (Architecture/Engineering/Construction) industry is facing a competitive world after it entered into the 21st century. Due to improper planning and scheduling, the construction projects face severe delays in completion. Most of the present day construction organisations operate in multiple project environments where more than one projects are to be managed simultaneously. But the advantages of planning and scheduling as multiple projects have not been utilized by these organisations. Change in multi-project planning and scheduling is inevitable and often frequent, therefore the traditional planning and scheduling approaches are no more feasible in scheduling multiple construction projects. The traditional scheduling tools like CPM and PERT do not offer any help in scheduling in a resource-constrained environment. This necessitated a detailed study to model the environment realistically and to make the allocation of limited resources flexible and efficient. This paper delineates about the proactive model which will help the project managers for scheduling the multiple construction projects.

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Enhanced Technique for Performance in Real Time Systems (실시간 시스템에서 성능 향상 기법)

  • Kim, Myung Jun
    • Journal of Information Technology Services
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    • v.16 no.3
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    • pp.103-111
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    • 2017
  • The real time scheduling is a key research area in high performance computing and has been a source of challenging problems. A periodic task is an infinite sequence of task instance where each job of a task comes in a regular period. The RMS (Rate Monotonic Scheduling) algorithm has the advantage of a strong theoretical foundation and holds out the promise of reducing the need for exhaustive testing of the scheduling. Many real-time systems built in the past based their scheduling on the Cyclic Executive Model because it produces predictable schedules which facilitate exhaustive testing. In this work we propose hybrid scheduling method which combines features of both of these scheduling algorithms. The original rate monotonic scheduling algorithm didn't consider the uniform sampling tasks in the real time systems. We have enumerated some issues when the RMS is applied to our hybrid scheduling method. We found the scheduling bound for the hard real-time systems which include the uniform sampling tasks. The suggested hybrid scheduling algorithm turns out to have some advantages from the point of view of the real time system designer, and is particularly useful in the context of large critical systems. Our algorithm can be useful for real time system designer who must guarantee the hard real time tasks.

Multiobjective Genetic Algorithm for Scheduling Problems in Manufacturing Systems

  • Gen, Mitsuo;Lin, Lin
    • Industrial Engineering and Management Systems
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    • v.11 no.4
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    • pp.310-330
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    • 2012
  • Scheduling is an important tool for a manufacturing system, where it can have a major impact on the productivity of a production process. In manufacturing systems, the purpose of scheduling is to minimize the production time and costs, by assigning a production facility when to make, with which staff, and on which equipment. Production scheduling aims to maximize the efficiency of the operation and reduce the costs. In order to find an optimal solution to manufacturing scheduling problems, it attempts to solve complex combinatorial optimization problems. Unfortunately, most of them fall into the class of NP-hard combinatorial problems. Genetic algorithm (GA) is one of the generic population-based metaheuristic optimization algorithms and the best one for finding a satisfactory solution in an acceptable time for the NP-hard scheduling problems. GA is the most popular type of evolutionary algorithm. In this survey paper, we address firstly multiobjective hybrid GA combined with adaptive fuzzy logic controller which gives fitness assignment mechanism and performance measures for solving multiple objective optimization problems, and four crucial issues in the manufacturing scheduling including a mathematical model, GA-based solution method and case study in flexible job-shop scheduling problem (fJSP), automatic guided vehicle (AGV) dispatching models in flexible manufacturing system (FMS) combined with priority-based GA, recent advanced planning and scheduling (APS) models and integrated systems for manufacturing.

A Basic Study for Accumulating Scheduling Knowledge-Base (공정관리 지식기반 구축을 위한 기초적 연구)

  • Jang Se-Han;Kim Kyung-Rai
    • Korean Journal of Construction Engineering and Management
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    • v.2 no.3 s.7
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    • pp.83-91
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    • 2001
  • Generally the level of accumulating scheduling knowledge-base in Korean construction companies is in the scheduling knowledge-base infrastructure construction phase and Even in top 10 construction companies, the level is in early scheduling knowledge activity phase. The principle causes of this situation are unawareness of importance to scheduling knowledge and absence of procedure related to scheduling knowledge-base. This research analyzes the problems to accumulate scheduling knowledge-base in Korean construction companies and proposes a procedure model to accumulate scheduling knowledge-base property, which adds items of scheduling knowledge-base infrastructure and scheduling knowledge activity to the existing scheduling procedures of Korean construction companies. Using procedure model for accumulating scheduling knowledge-base, Korean construction companies can develop a new scheduling procedure and accumulate scheduling knowledge accordingly. If scheduling knowledge were accumulated property according to the procedure, a framework for knowledge management system could be provided.

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Work scheduling method by applying knowledge engineering supported by mathematical programming technique

  • Kurihara, Kenzo
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.215-218
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    • 1996
  • In work scheduling problems, scheduling constraints are not absolutely rigid; they may be changed depending on the scheduling aspect effected. In order to cope with changes in scheduling constraints and assignment strategies and to optimize scheduling results quickly, this paper will propose a new scheduling method which combines knowledge engineering and mathematical programming techniques.

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Performance Verification of the Modified Gain Scheduling Controller by Speed Control of a DC Motor (DC 모터 제어를 통한 개선된 게인 스케줄링 제어기의 성능 검증)

  • Cheon, Min-Kyu;Park, Mig-Non;Hyun, Chang-Ho;Lee, Hee-Jin
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.312-314
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    • 2006
  • This paper describes performance of the modified gain scheduling controller by speed control of a DC motor. The modified gain scheduling controller can perform tracking at more than one equilibrium points. The modified gain scheduling controller which considers transient response according to added zero shows better result of tracking performance than the unmodified gain scheduling controller shows.

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QoS-based Scheduling Algorithm for ATM in the Broadband Access Networks (가입자망에서의 서비스 품질 기반ATM 스케줄링 알고리즘)

  • 정연서;오창석
    • Journal of the Korea Society of Computer and Information
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    • v.6 no.1
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    • pp.67-73
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    • 2001
  • This paper proposes a new scheduling algorithm for broadband ATM access network. The existed scheduling algorithms (Train, Chao. Dynamic scheduling algorithm) have high cell loss rate and waste channel. These proposed mechanism utilize to control of multimedia services based on the quality of service level of the input traffic This paper suggests a functional architecture of scheduling and the scheduling algorithm to satisfy various QoS requirements. The performance measures of interest, namely steady-state cell loss probability and average delay, average delay, are discussed by simulation results.

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Survey of Evolutionary Algorithms in Advanced Planning and Scheduling

  • Gen, Mitsuo;Zhang, Wenqiang;Lin, Lin
    • Journal of Korean Institute of Industrial Engineers
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    • v.35 no.1
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    • pp.15-39
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    • 2009
  • Advanced planning and scheduling (APS) refers to a manufacturing management process by which raw materials and production capacity are optimally allocated to meet demand. APS is especially well-suited to environments where simpler planning methods cannot adequately address complex trade-offs between competing priorities. However, most scheduling problems of APS in the real world face both inevitable constraints such as due date, capability, transportation cost, set up cost and available resources. In this survey paper, we address three crucial issues in APS, including basic scheduling model, job-shop scheduling (JSP), assembly line balancing (ALB) model, and integrated scheduling models for manufacturing and logistics. Several evolutionary algorithms which adapt to the problems are surveyed and proposed; some test instances based on the practical problems demonstrate the effectiveness and efficiency of evolutionary approaches.

Integrated Job Shop Scheduling considering Alternative Machines and Operation Sequence (대체기계와 공정순서를 고려한 Job Shop에서의 통합 일정계획)

  • 최형림;박병주;박용성;강무홍
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.11a
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    • pp.85-88
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    • 2003
  • In case that any jobs in a Job Shop can be scheduled on more than one machine and may have flexible operation sequences, with considering such case it is very difficult and complex to make the optimal process plans and scheduling. But they should be considered for an integrated model to perform more effective process planning and scheduling in this job shop problem. In this paper, we propose GA-based scheduling method to integrate effectively the problem of alternative machines, alternative operation sequences and scheduling. The performance of proposed GA is evaluated through comparing integrated scheduling with not integrated scheduling in molding company with alternative machines and operation sequences. Also, we use benchmark problems to evaluate performance. The scheduling method in this research will apply usefully to real world scheduling problems.

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