• Title/Summary/Keyword: short-term scheduling

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Short-term Operation Scheduling Using Possibility Fuzzy Theory on Cogeneration System Connected with Auxiliary Devices (열병합발전시스템에서 가능성 퍼지이론을 적용한 단기운전계획수립)

  • Kim, Sung-Il;Jung, Chang-Ho;Lee, Jong-Beom
    • Journal of Energy Engineering
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    • v.6 no.1
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    • pp.19-25
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    • 1997
  • This paper presents the short-term operation scheduling on cogeneration system connected with auxiliary equipment by using the possibility fuzzy theory. The possibility fuzzy theory is a method to obtain the possibility boundary of the solution from the fuzzification of coefficients. Simulation is carried out to obtain the boundary of heat production in each time interval. Simulation results show the flexible operation boundary to establish effectively operation scheduling.

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Models for Scheduling Individual Jet Aircraft

  • Yang, Hong-Suk
    • International Journal of Quality Innovation
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    • v.10 no.2
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    • pp.19-27
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    • 2009
  • This paper considers the short term fleet scheduling problem as described by Keskinocak and Tayur (1998). Fleet scheduling may directly affect the service quality of fractional jet aircraft business. The contributions of this paper are two: (i) we show how their model is easily implemented in a standard modeling language, LINGO, and (ii) an alternate formulation is given which is expected to perform better on large, difficult problems.

A Study on Scheduling by Mixed Dispatching rule in Flexible Manufacturing Systems (유연생산시스템에서 혼합할당규칙에 의한 일정계획에 관한 연구)

  • 이동진;노인규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.47
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    • pp.35-45
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    • 1998
  • Scheduling problem in Flexible Manufacturing Systems(FMS) is complex because of various situation of Manufacturing Systems. Especially, in case of short-term scheduling demanding high efficiency, low cost at short-period, efficient scheduling is a serious problem. To solve this problem, many dispatching rules are developed. But, it leave much to be desired, because real situation in shop floor is complex and real-time scheduling is needed in real manufacturing shop floor. In this paper, search algorithm that allocate different dispatching rules to each machine is presented to complement lack of dispatching rule and develop practical real-time scheduling system. The search algorithm is described in detail. First, algorithm detect machine breakdown, evaluate each dispatching rule. dispatching rules for each machine meeting performance criteria are ranked. The algorithm selects new dispatching nile for bottleneck machine. The effectivenes and efficiency of the mixed dispatching rule and search algorithm is demonstrated.

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A Study on the Optimization Analysis of Tactical Ship Scheduling (전술적 선박 스케쥴링의 최적화 분석에 관한 연구)

  • 이경근;김시화
    • Journal of the Korean Institute of Navigation
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    • v.18 no.2
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    • pp.57-67
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    • 1994
  • This paper treats the optimization analysis of tactical ship scheduling problems in the world seaborne bulk trade. The authors use the term 'tactial' to describe the ship scheduling problem where the owners should employ skillful tactics as an expedient toward gaining the higher profits per period in short term. Relevent research and related problems on ship scheduling problems are reviewed briefly and a model for the tactical ship scheduling problem formulated as Set Problem is introduced by modifying the previous work of Fisher(1989). The reality and practicability of the model is validated by some ship-ping statistics. Proper solution approaches are outlined in the context of computational tractability in tackling the Mixed Integer Propramming. Some underlying consideration for the computational experiment is also mentioned. The authors conclude the paper with the remarks on the need of user-friendly Decision Support System for ship scheduling under varying decision environment.

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Packet Loss Fair Scheduling Scheme for Real-Time Traffic in OFDMA Systems

  • Shin, Seok-Joo;Ryu, Byung-Han
    • ETRI Journal
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    • v.26 no.5
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    • pp.391-396
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    • 2004
  • In this paper, we propose a packet scheduling discipline called packet loss fair scheduling, in which the packet loss of each user from different real-time traffic is fairly distributed according to the quality of service requirements. We consider an orthogonal frequency division multiple access (OFDMA) system. The basic frame structure of the system is for the downlink in a cellular packet network, where the time axis is divided into a finite number of slots within a frame, and the frequency axis is segmented into subchannels that consist of multiple subcarriers. In addition, to compensate for fast and slow channel variation, we employ a link adaptation technique such as adaptive modulation and coding. From the simulation results, our proposed packet scheduling scheme can support QoS differentiations while guaranteeing short-term fairness as well as long-term fairness for various real-time traffic.

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An Expert System for Short-Term Generation Scheduling of Electric Power Systems (전력계통의 단기 발전계획 기원용 전문가시스템)

  • Yu, In-Keun
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.8
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    • pp.831-840
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    • 1992
  • This paper presents an efficient short-term generation scheduling method using a rule-based expert/consulting system approach to assist electric energy system operators and planners. The expert system approach is applied to improve the Dynamic Programming(DP) based generation scheduling algorithm. In the selection procedure of the feasible combinations of generating units at each stage, automatic consulting on the manipulation of several constraints such as the minimum up time, the minimum down time and the maximum running time constraints of generating units will be performed by the expert/consulting system. In order to maximize the solution feasibility, the aforementioned constraints are controlled by a rule-based expert system, that is, instead of imposing penalty cost to those constraint violated combinations, which sometimes may become the very reason of no existing solution, several constraints will be manipulated within their flexibilities using the rules and facts that are established by domain experts. In this paper, for the purpose of implementing the consulting of several constraints during the dynamic process of generation scheduling, an expert system named STGSCS is developed. As a building tool of the expert system, C Language Integrated Production System(CLIPS) is used. The effectiveness of the proposed algorithm has been demonstrated by applying it to a model electric energy system.

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A Study on the Construction of Detail Integrated Scheduling System of Ship Building Process (선박건조공정의 미세 통합 일정 관리 체계 구축에 관한 연구)

  • Kim, Yong-Seop;Lee, Dae-Hyung
    • Journal of the Society of Naval Architects of Korea
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    • v.44 no.1 s.151
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    • pp.48-54
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    • 2007
  • Higher productivity and less cost during the manufacturing process of ships are required to maintain international competitiveness of modern shipbuilding industries. The integrated hull/ outfitting/ painting scheduling(IHOP) process is a final point, where logistics are finally being integrated and upcoming schedules are made. Therefore, more profits are expected from IHOP by effective management. In this thesis, IHOP is proposed in order to solve how to choose block erection date with IHOP scheduling logic. The result of IHOP scheduling is highly advised to utilize fabrication, outfitting shops. A standardized operation and load of resource will eventually be applied in long-term time span point of view for this will make it easy to enable capacity planning and workforce planning. It is also expected to eliminate inefficiency in overtime work and efficiently utilize manpower in short-term.

Long-Term Container Allocation via Optimized Task Scheduling Through Deep Learning (OTS-DL) And High-Level Security

  • Muthakshi S;Mahesh K
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.4
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    • pp.1258-1275
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    • 2023
  • Cloud computing is a new technology that has adapted to the traditional way of service providing. Service providers are responsible for managing the allocation of resources. Selecting suitable containers and bandwidth for job scheduling has been a challenging task for the service providers. There are several existing systems that have introduced many algorithms for resource allocation. To overcome these challenges, the proposed system introduces an Optimized Task Scheduling Algorithm with Deep Learning (OTS-DL). When a job is assigned to a Cloud Service Provider (CSP), the containers are allocated automatically. The article segregates the containers as' Long-Term Container (LTC)' and 'Short-Term Container (STC)' for resource allocation. The system leverages an 'Optimized Task Scheduling Algorithm' to maximize the resource utilisation that initially inquires for micro-task and macro-task dependencies. The bottleneck task is chosen and acted upon accordingly. Further, the system initializes a 'Deep Learning' (DL) for implementing all the progressive steps of job scheduling in the cloud. Further, to overcome container attacks and errors, the system formulates a Container Convergence (Fault Tolerance) theory with high-level security. The results demonstrate that the used optimization algorithm is more effective for implementing a complete resource allocation and solving the large-scale optimization problem of resource allocation and security issues.

Uplink/downlink - combined Fair Queueing Scheduling for Wireless TDMA/TDD Systems (무선 TDMA/TDD 시스템에서의 상.하향 링크 통합 페어큐잉 스케쥴링)

  • 최효현;최명환
    • Proceedings of the IEEK Conference
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    • 2002.06a
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    • pp.93-96
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    • 2002
  • Fair Queueing has been studied only on wired network. When it is applied to wireless netowork, the collision phenomenon makes a problem.'rho information of queue of MT cannot be transferred to fair queueing algorithm In real time easily. We propose wireless fair queueing scheduler that protects short term farirness and long term fairness. We developed it in TDMA/TDD enviroment. Our scheme also supports uplink and downlink at the same time. And it can make subframe boundary based on fair scheduling algorithm.

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MILP model for short-term scheduling of multi-purpose batch plants with batch distillation process

  • Ha, Jin-Juk;Lee, Euy-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1826-1829
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    • 2003
  • Fine chemical production must assure high-standard product quality as well as characterized as multi-product production in small volumes. Installing high-precision batch distillation is one of the common elements in the successful manufacturing of fine chemicals, and the importance of the process operation strategy with quality assurance cannot be overemphasized. In this study, we investigate the optimal operation strategy and production planning of a sequential multi-purpose plants consisting of batch processes and batch distillation with unlimited intermediate storage. We formulated this problem as an MILP model. A mixed-integer linear programming model is developed based on the time slot, which is used to determine the production sequence and the production path of each batch. Illustrative examples show the effectiveness of the approach.

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