• Title/Summary/Keyword: Process scheduling algorithm

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Generation Scheduling with Large-Scale Wind Farms using Grey Wolf Optimization

  • Saravanan, R.;Subramanian, S.;Dharmalingam, V.;Ganesan, S.
    • Journal of Electrical Engineering and Technology
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    • v.12 no.4
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    • pp.1348-1356
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    • 2017
  • Integration of wind generators with the conventional power plants will raise operational challenges to the electric power utilities due to the uncertainty of wind availability. Thus, the Generation Scheduling (GS) among the online generating units has become crucial. This process can be formulated mathematically as an optimization problem. The GS problem of wind integrated power system is inherently complex because the formulation involves non-linear operational characteristics of generating units, system and operational constraints. As the robust tool is viable to address the chosen problem, the modern bio-inspired algorithm namely, Grey Wolf Optimization (GWO) algorithm is chosen as the main optimization tool. The intended algorithm is implemented on the standard test systems and the attained numerical results are compared with the earlier reports. The comparison clearly indicates the intended tool is robust and a promising alternative for solving GS problems.

Scheduling Tasks for a Time Sharing Computer System with a Single Processor

  • 차동완
    • Communications of the Korean Institute of Information Scientists and Engineers
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    • v.5 no.1
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    • pp.04-10
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    • 1987
  • We consider a time sharing computer system with a single processor where tasks ofK different types arrive at the system according to independent time homogeneous Poisson processes from outside. A task, after given a quantum for processing, leaves the system, or changes the type and rejoins the system according to specified probabilitycs. While many existing priority time sharing models determine the priorities of tasks strictly by their service time requirements, this paper develops a new scheduling rule wherein the importances or urgencies in addition to the service time requirements of tasks are counted, by inposing an appropriate reward structure on the system. Also presented is the algorithm through which to determine the rankings of K types according to this new scheduling rule.

Efficient Channel Scheduling Technique Using Release Time Unscheduled Channel Algorithm in OBS WDM Networks (OBS WDM 망에서 비 할당된 채널 개방시간을 이용한 효율적인 채널 스케줄링 기법)

  • Cho Seok-man;Kim Sun-myeng;Choi Dug-kyoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10A
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    • pp.912-921
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    • 2005
  • Optical burst switching(OBS) is a promising solution for building terabit optical routers and realizing If over WDM. Channel scheduling Algorithm for reduce contention is one of the major challenges in OBS. We address the issue of how to provide basic burst channel scheduling in optical burst switched WDM networks with fiber delay lines(FDLs). In OBS networks the control and payload components or a burst are sent separately with a time gap. If CHP arrives to burst switch node, because using scheduling algorithm for data burst, reservation resources such as wavelength and transmit data burst without O/E/O conversion, because contention and void between burst are happened at channel scheduling process for data burst that happened the link utilization and bust drop probability Existent proposed methods are become much research to solve these problems. Propose channel scheduling algorithm that use Release Time of bust to emphasize clearance between data and data dissipation that is happened in data assignment in this treatise and maximize bust drop probability and the resources use rate (RTUC : Release Time Unscheduled Channel). As simulation results, Confirmed that is more superior in terms of data drop and link utilization than scheduling algorithm that is proposed existing. As simulation results, confirmed improved performance than scheduling algorithm that is proposed existing in terms of survival of burst, efficiency resource and delay. However, In case load were less, degradation confirmed than existent scheduling algorithm relatively, and confirmed that is superior in data drop aspect in case of load increased.

A Genetic Algorithm Approach to Job Shop Scheduling Considering Alternative Process Plans (대체 공정을 도입한 유전 알고리즘 응용의 작업 일정 계획)

  • Park, Ji-Hyung;Choi, Hoe-Ryeon;Kim, Young-Hui
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.4
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    • pp.551-558
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    • 1998
  • In this paper, a job shop scheduling system is developed which can cope with the changes of shop floor status with flexibility. This system suggests near optimal sequence of operations by using Genetic Algorithm which considers alternative process plans. The Genetic Algorithm proposed in this paper has some characteristics. The mutation rate is differentiated in order to enhance the chance to escape a local optimum and to assure the global optimum. And it employs the double gene structure to easily make the modeling of the shop floor. Finally, the quality of its solution and the computational time are examined in comparison with the method of a Simulated Annealing.

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A rule-based scheduling system for automated machining

  • Ahn, Jaekyoung
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1992.04b
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    • pp.249-257
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    • 1992
  • An automated machining system involves concurrent use of manufacturing resources, alternative process plans, and flexible routings. High investment in the installation of automated facilities requires an efficient scheduling system that is able to allocate the resources specified for operations over a scheduling horizon. The primary emphasis of this paper is to generate schedules that accurately reflect details of the automated environment and the objectives stated for the system. In this paper, a scheduling algorithm for automated machining is presented. Using the previous simulation research for this topic, a rule-based scheduling system is constructed. An architecture for an intelligent scheduling system is proposed, and the system has a high potential to provide efficient schedules based on the task-specific knowledge for the dynamic scheduling environment

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An efficient circuit design algorithm considering constraint (제한조건을 고려한 효율적 회로 설계 알고리즘)

  • Kim, Jae Jin
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.1
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    • pp.41-46
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    • 2012
  • In this paper, An efficient circuit design algorithm considering constraint is proposed. The proposed algorithm sets up in time constraint and area constraint, power consumption constraint for a circuit implementation. First, scheduling process for time constraint. Select the FU(Function Unit) which is satisfied with time constraint among the high level synthesis results. Analyze area and power consumption of selected FUs. Constraint set for area and power constraint. Device selection to see to setting condition. Optimization circuit implementation in selected device. The proposed algorithm compared with [7] and [8] algorithm. Therefore the proposed algorithm is proved an efficient algorithm for optimization circuit implementation.

Customer Order Scheduling Problems with Fixed Machine-Job Assignment

  • Yang, Jae-Hwan
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.05a
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    • pp.615-619
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    • 2004
  • This paper considers a variation of customer order scheduling problems. The variation is the case where machine-job assignment is fixed, and the objective is to minimize the sum of the completion times of the batches. In customer order scheduling problems, jobs are dispatched in batches. While a machine can process only one job at a time, multiple machines can simultaneously process jobs in a batch. We first establish a couple of lower bounds. Then, we develop a dynamic programming (DP) algorithm that runs in exponential time on the number of batches when there exist two machines. For the same problem with arbitrary number of machines, we present two simple heuristics, which use simple scheduling rules such as shortest batch first and shortest makespan batch first rules. Finally, we empirically evaluate the heuristics.

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Near optimal production scheduling for multi-unit batch process

  • Kim, Kyeong-Sook;Cho, Young-Sang
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1718-1723
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    • 1991
  • The determination of a production sequence is an important problem in a batch process operation. In this paper a new algorithm for a near optimal production sequence of N product in an M unit serial multiproduct batch process is proposed. The basic principle is the same as that of Johnson's algorithm for two-unit UIS system. Test results on a number of selected examples exhibit the superiority over previously reported results. In addition, a tabulation technique is presented to calculate the makespan of a given sequence of production for all processing units under UIS mode.

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A Genetic Algorithm for Scheduling of Trucks with Inbound and Outbound Process in Multi-Door Cross Docking Terminals (다수의 도어를 갖는 크로스도킹 터미널에서 입고와 출고를 병행하는 트럭일정계획을 위한 유전알고리즘)

  • Joo, Cheol-Min;Kim, Byung-Soo
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.3
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    • pp.248-257
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    • 2011
  • Cross docking is a logistics management concept in which items delivered to a terminal by inbound trucks are immediately sorted out, routed and loaded into outbound trucks for delivery to customers. Two main advantages by introducing a cross docking terminal are to consolidate multiple smaller shipment into full truck load and remove storage and order picking processes to save up logistics costs related to warehousing and transportation costs. This research considers the scheduling problem of trucks in the cross docking terminals with multi-door in an inbound and outbound dock, respectively. The trucks sequentially deal with the storage process at the one of inbound doors and the shipping process at the one of the outbound doors. A mathematical model for an optimal solution is derived, and genetic algorithms with two different chromosome representations are proposed. To verify performance of the GA algorithms, we compare the solutions of GAs with the optimal solutions and the best solution using randomly generated several examples.

An Improved Branch-and-Bound Algorithm for Scheduling Jobs on Identical Machines

  • Park, Sung-Hyun
    • Journal of Korean Institute of Industrial Engineers
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    • v.1 no.2
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    • pp.73-81
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    • 1975
  • In an earlier paper ('Scheduling Jobs on a Number of Identical Machines' by Elmaghraby and Park, March 1974, AIIE Transactions) a branch-and-bound algorithm was developed for the sequencing problem when all jobs are available to process at time zero and are independet (i.e., there are not a priori precedence relationships among jobs.). However, the amount of computation required by the algorithm was not considered to be short if more than 50 jobs were processed. As an effort to improve the algorithm, the present paper modifies the implicit enumeration procedure in the algorithm so that moderately large problems can be treated with what appears to be a short computational time. Mainly this paper is concerned with improving the lower bound in the implicit enumeration procedure. The computational experiences with this new branch-and-bound algorithm are given.

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