• 제목, 요약, 키워드: scheduling

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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.

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.

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
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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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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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    • 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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A Genetic Algorithm-based Scheduling Method for Job Shop Scheduling Problem (유전알고리즘에 기반한 Job Shop 일정계획 기법)

  • 박병주;최형림;김현수
    • Korean Management Science Review
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    • v.20 no.1
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    • pp.51-64
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    • 2003
  • The JSSP (Job Shop Scheduling Problem) Is one of the most general and difficult of all traditional scheduling problems. The goal of this research is to develop an efficient scheduling method based on genetic algorithm to address JSSP. we design scheduling method based on SGA (Single Genetic Algorithm) and PGA (Parallel Genetic Algorithm). In the scheduling method, the representation, which encodes the job number, is made to be always feasible, initial population is generated through integrating representation and G&T algorithm, the new genetic operators and selection method are designed to better transmit the temporal relationships in the chromosome, and island model PGA are proposed. The scheduling method based on genetic algorithm are tested on five standard benchmark JSSPs. The results were compared with other proposed approaches. Compared to traditional genetic algorithm, the proposed approach yields significant improvement at a solution. The superior results indicate the successful Incorporation of generating method of initial population into the genetic operators.

SCHEDULING TECHNIQUE FOR CONTROL STEP (스케듈링 기법 연구)

  • JeongYoungSong;NamWooBack
    • Journal of the Korean Geophysical Society
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    • v.4 no.3
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    • pp.163-173
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    • 2001
  • This paper deals with scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informaion trom the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth - order elliptic wave filter of a standard benchmark moedl, and then it is drawing up T.N matrix table by the number resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource th use this table. All of existing list scheduling techniques determine the priority function first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

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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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Real-Time DBR Scheduling in Internet Based Make-to-Order Manufacturing (인터넷을 통한 주문생산환경에서의 실시간 생산 DBR 스케줄링)

  • Han, Young-Geun;Kim, Yeon-Kyun
    • IE interfaces
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    • v.14 no.4
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    • pp.341-347
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    • 2001
  • This paper describes a real-time manufacturing scheduling system on Internet using DBR(Drum-Buffer-Rope) scheduling method. We intend to change company-oriented manufacturing scheduling, which has been used at most manufacturing companies, to customer-oriented manufacturing scheduling. Customers can not only choose product kinds, quantities and order due dates, but also evaluate optimum order due date by themselves in real-time through internet and then the results will be converted into practical manufacturing scheduling. If the company cannot meet the customer order due date, it will offer reliable and accurate information to the customers by suggesting the earliest order due date. To evaluate the customer order due date in real time, companies should be able to estimate their accurate production capacity. This research uses Goldratt's DBR scheduling method to realize that function. The DBR scheduling does not recognize the production capacity of the whole company, but only of the constraint resources which have a great effect on the company throughput. Thus, it can improve the customer service level as well as the profit by performing more dynamic and reliable scheduling through Internet.

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Scheduling Technique for Control Step (제어구간에 의한 스케듈링 기법)

  • Song, Jeong-Young;Back, Nam-Woo
    • The Journal of Engineering Research
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    • v.4 no.1
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    • pp.35-45
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    • 2002
  • This paper deals with the scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informations from the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth – order elliptic wave filter of a standard benchmark model, and then it is drawing up T.N matrix table by the number of resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource to use this table. All of existing list scheduling techniques determine the priority functions first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

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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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    • 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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