• Title/Summary/Keyword: priority schedule

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Development of a Two-Phase Heuristic Method for the Enhancement of a Production Schedule (생산일정계획 성능향상을 위한 2단계 휴리스틱 방법의 개발)

  • Hong, Yun-Ho;Kim, Sheung-Kown;Kim, Sun-Uk;Lee, Jun-Youl
    • Journal of Korean Institute of Industrial Engineers
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    • v.20 no.3
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    • pp.65-77
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    • 1994
  • There are so many situations in which production schedules need to be rescheduled, due to the uncertainty or dynamic characteristics existing in manufacturing environment. Under the circumstances, it is necessary to build a system which helps a schedule manager understand the dynamic situations and reflect his insight into the system easily. We developed a system that can improve a production schedule. The system consists of a schedule editor and a schedule generator. The schedule editor, a rule-based system, always keeps a schedule feasible by keeping track of local changes in the revised one. The schedule generator consists of a two-phase heuristic method. In the lst phase it generates a schedule by a priority rule with Giffler and Thompson algorithm then it improves the performance in terms of the makespan in the 2nd phase. Experimental results show that, most of the times, the system generates a better schedule than the one with ordinary priority rules only.

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Maximal-Flow-Problem with transit priority in a track (통과 우선순위가 있는 선로의 최대 흐름문제)

  • 이달상;김만식
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.21
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    • pp.111-117
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    • 1990
  • This paper treats the problem to schedule for train with low transit priority so as to maximizing the number that can be sent during given time without interfering with the fixed schedule for train with high transit priority in a track. We transform the this problem into Time-Expanded Network without traverse time through application of Ford-Fulkerson Model, develop a TENET GENerator(TENETGEN) and obtain the data of TENET using developed TENETGEN. Finally, we seek the optimal solution to these data with Dinic's Maximal-Flow Algorithm and examine the availability of our procedures in personal computer.

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A maximal-Flow Scheduling Using time Expanded Network in a track (시간 전개형 네트워크를 이용한 선로의 최대흐름 스케쥴링)

  • 이달상;김만식
    • Journal of Korean Society of Transportation
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    • v.8 no.2
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    • pp.67-75
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    • 1990
  • This paper treats the problem to schedule for trains with how transit priority so as to maximizing the number that can be sent during given time periods without interfering with the fixed schedule for train with high transit priority in a track. We transform the this problem into Time Expanded Network without traverse time through application of Ford and Fulkerson Model and construct the Enumeration Algorithm for solutions using TENET Generator (TENETGEN). Finally, we compare our algorithm with Dinic's Maximal-Flow Algorithm and examine the avaliability of our procedures in personal computer.

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Direct Load Control using Priority Based Dynamic Programming Technique (동적 프로그래밍 기법을 이용한 직접부하제어 알고리즘 개발)

  • Kim, Tae-Hyon;Lee, Jong-Soo;Shin, Myong-Chel;Choi, Sang-Yeol
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.463-465
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    • 2003
  • This paper adopts the methods of dynamic programming based on priority and the objective function is to maximize the amount of priority. The Purpose of this work is to schedule the direct load control with approciate constrints. To demonstrate the effectiveness of the study, sample data is used about 54 load. And the results of sample are described in this.

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Development of an Application Software for the Die-Production Information Management (금형 생산관리를 위한 응용 소프트웨어의 개발)

  • Kong, Myung-Dal;Kim, Jung-Ja
    • IE interfaces
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    • v.9 no.2
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    • pp.143-158
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    • 1996
  • This paper deals with the development of a software module for production planning and scheduling activities of an actual die-production management system. Scheduling problems, such as master schedule and detailed schedule, are the focal point of the whole article and they are considered in terms of operation procedures. Schedule-explosion module and load levelling module are the essential components of schedule management. The scheduling module allocates the resources, determines the process priority and the planned start and completion dates of processes. Rescheduling can be done to manipulate unforeseen situations that schedule is delayed owing to inducing defectives, machine breakdowns and lumpy demands. This study indicates a practical model for the die-producation management and helps to apply it for jobs in the real situation.

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An open Scheduling Framework for QoS resource management in the Internet of Things

  • Jing, Weipeng;Miao, Qiucheng;Chen, Guangsheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.9
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    • pp.4103-4121
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    • 2018
  • Quality of Service (QoS) awareness is recognized as a key point for the success of Internet of Things (IOT).Realizing the full potential of the Internet of Things requires, a real-time task scheduling algorithm must be designed to meet the QoS need. In order to schedule tasks with diverse QoS requirements in cloud environment efficiently, we propose a task scheduling strategy based on dynamic priority and load balancing (DPLB) in this paper. The dynamic priority consisted of task value density and the urgency of the task execution, the priority is increased over time to insure that each task can be implemented in time. The scheduling decision variable is composed of time attractiveness considered earliest completion time (ECT) and load brightness considered load status information which by obtain from each virtual machine by topic-based publish/subscribe mechanism. Then sorting tasks by priority and first schedule the task with highest priority to the virtual machine in feasible VMs group which satisfy the QoS requirements of task with maximal. Finally, after this patch tasks are scheduled over, the task migration manager will start work to reduce the load balancing degree.The experimental results show that, compared with the Min-Min, Max-Min, WRR, GAs, and HBB-LB algorithm, the DPLB is more effective, it reduces the Makespan, balances the load of VMs, augments the success completed ratio of tasks before deadline and raises the profit of cloud service per second.

Influence Factors and Management based on Phase of Building Construction for the Improvement of Post Occupancy Indoor Air Quality

  • Lim, Hyoung-Chul
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.6
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    • pp.576-586
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    • 2011
  • In recent years, pollution in residential spaces has been a significant area of concern. In particular, the indoor air quality (IAQ) of an apartment building before occupancy, which is related to the interior material, is a serious problem. Unlike previous research, which has mainly focused on pollution control after construction, this study has derived influencing factors and priority of management with a controlling schedule for IAQ. The objectives of this research are 1) control of schedule or improvement of management for IAQ, 2) distribution of responsibility to the parties concerned (factory, material company, construction company, design and engineering, occupancy). The results show the relative priority of the four major items in wall?based apartment buildings and in column?based apartment buildings. An analysis of the parties responsible for improvement based on the IAQ results shows more efforts to improve IAQ are needed in material factories and engineering/design companies.

A Dynamic Scheduling Method for Mobile Broadcasting Using User Profiles (사용자 프로파일을 활용한 모바일 방송에서의 동적 스케줄링)

  • Park, Mee-Hwa;Lee, Yong-Kyu
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.2 s.46
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    • pp.111-121
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    • 2007
  • In mobile computing environments, data broadcasting is widely used to resolve the problem of limited power and bandwidth of mobile equipments. However, the previous broadcast scheduling methods can be inefficient in the environment where the user requests change dynamically since they are based on static data requests. Moreover, a high-priority user can wait long for infrequently requested data because they never consider the priority of listeners. In this paper, we propose a new broadcast scheduling method that reflects dynamic changes of user requests using user profiles. It also reflects user priorities to reduce the access time of high-priority users. We evaluate the performance of the proposed method through simulation.

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Study on Preemptive Real-Time Scheduling Strategy for Wireless Sensor Networks

  • Zhi-bin, Zhao;Fuxiang, Gao
    • Journal of Information Processing Systems
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    • v.5 no.3
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    • pp.135-144
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    • 2009
  • Most of the tasks in wireless sensor networks (WSN) are requested to run in a real-time way. Neither EDF nor FIFO can ensure real-time scheduling in WSN. A real-time scheduling strategy (RTS) is proposed in this paper. All tasks are divided into two layers and endued diverse priorities. RTS utilizes a preemptive way to ensure hard real-time scheduling. The experimental results indicate that RTS has a good performance both in communication throughput and over-load.

Influence Factors of Aerial Environment on Project Schedule Management

  • Hong, Jun-pyo;Lim, Hyoung-chul
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.608-611
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    • 2015
  • The objectives of this research are 1) control of schedule or improvement of management for aerial environment, 2) distribution of responsibility to the parties concerned (factory, material company, construction company, design and engineering, occupancy). The results show the relative priority of the four major items in wall-based apartment buildings and in column-based apartment buildings. An analysis of the parties responsible for improvement based on the IAQ results shows more efforts to improve IAQ are needed in material factories and engineering/design companies.

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