• 제목, 요약, 키워드: Turnaround time

검색결과 73건 처리시간 0.039초

OSF/1 기반 SRT 스케쥴러의 성능 향상 (Performance Improvement of Soft Real-Time Scheduler in OSF/1)

  • 이승호;허신
    • 한국정보처리학회논문지
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    • v.4 no.1
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    • pp.246-254
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    • 1997
  • 본 논문은 SRT 시스템에서 고정 우선순위 정책을 사용하는 쓰레드가 기존보다 더 빠른 응답시간과 반환시간을 갖도록 하기 위한 개선된 스케쥴링 모델과 알고리즘을 제시하였다. 보조 실행 큐를 첨가하여 고정 우선순위 정책을 사용하는 쓰레드의 빠른 실행 및 에이징(aging)에 사용하였다. 시뮬레이션을 통하여 기존의 방식과 비교하였 으며 그 결과, 새로 제안된 모델의 경우, 고정 우선순위 쓰레드의 반응시간과 반환시 간이 기존보다 향상되었다.

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Gemini Observatory - a new opportunity for the Korean community

  • Kissler-Patig, Markus
    • 천문학회보
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    • v.39 no.2
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    • pp.40-40
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    • 2014
  • Through KASI, Korean astronomers will have access to the Gemini Observatory starting in 2015. Gemini operates two optical/infrared 8m-class telescopes: one on the northern hemisphere in Hawaii, one on the southern hemisphere in Chile. Both are equipped with state of the art instruments and adaptive optics systems that will be presented. Gemini also offers the opportunity for instrument development and welcomes visiting instruments. In terms of operations, Gemini offers to its partners three ways of applying for time: through semester-basis calls for standard programs, through yearly calls for Large and Long Programs, and through monthly calls for fast turnaround programs. Gemini operates in queue mode (observing for the principal investigators and allowing flexibility in the time domain), as well as in the classical visitor mode (where principal investigators come to the telescope). I will explain the requirements and advantages of all these modes as well as a full update on the Gemini Observatory.

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플라스틱 렌즈 사출에서의 변위 해석에 관한 연구 (A Study on the Displacement Analysis in the Injection Molding for the Plastic Lens)

  • 이주상;윤상진;김치균
    • 한국기계기술학회지
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    • v.19 no.4
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    • pp.567-572
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    • 2017
  • Smart phones are currently the most popular electronic devices with high volume production activities driven by high demand and requirements for rapid turnaround time. The changes of displacement were analyzed according to a variable of the gate size and runner system. The radial type and gate with large size were shown that better results in displacement. While the design and production of lenses, the key component of a camera, still need to be improved, the current technology has run into its limit with regard to trends in size and weight reduction. In this study, an injection molding analysis was performed on plastic lenses that are widely employed for smart phone cameras. Specifically, the displacement of lenses at the time of injection molding was studied by varying the gate size and runner system.

반자동화 컨테이너터미널의 RMGC 운영방식 비교 분석 (A Study of Comparison with the Operating Priority Rules of RMGC on Semi-Automated Container Terminal)

  • 김찬호;하태영;양홍석
    • 한국경영과학회지
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    • v.35 no.2
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    • pp.1-17
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    • 2010
  • This paper aims to compare four operating priority rules of RMGC (Rail Mounted Gantry Crane) used in semi-automated container terminal. The four priority rules employed in this paper are FCFS (First-come-first-served), LCFS (Last-come-first-served), TOS (Turn-over-served) and NFS (Nearest-first-served). And to compare the four operating priority rules, this paper analyzed productivity of RMGC and CC (Container Crane), waiting time of YT (Yard Truck) and RT (Road Truck) in container yard, and turnaround time of RT in container terminal of each priority rule by using stevedoring simulation. As a result, NFS was evaluated as the best rule to improve the overall productivity of container terminal in terms of all criteria.

유비쿼터스 환경에서 멀티 에이전트 시스템을 위한 우선순위 기반 메시지 스케줄링 기법 (Priority-based Message Scheduling for Multi-agent System in Ubiquitous Environment)

  • 윤양석;윤희용
    • 인터넷정보학회논문지
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    • v.9 no.1
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    • pp.137-143
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    • 2008
  • 유비쿼터스 환경에서 멀티 에이전트 시스템은 지능화 서비스를 제공하는데 유용하다. 본 논문에서는 멀티 에이전트 시스템에서의 통신 성능을 향상시키기 위한 새로운 스케줄링 서비스 모델을 제안한다. 이 모델은 에이전트 간에 교환되는 메시지의 수와 형식화된 ACL 메시지를 기반으로 가중치를 적용하여 우선순위를 할당한다. 제안된 방식은 JADE 플랫폼과 비교하여 메시지 당 처리시간과 총 소요시간을 적게 하는 것을 실험을 통해 보여준다. 더욱이 제안된 방식은 확장성 있는 메시지 처리 시스템을 만들 수 있게 한다.

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최소차량운용문제에 대한 실용적 해법 (A pragmatic algorithm for the Minimum Railway Stock Maintenance Routing Problem)

  • 홍성필;김경민;이경식;박범환;홍순흠
    • 한국경영과학회:학술대회논문집
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    • pp.25-32
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    • 2006
  • Given a schedule of train to be routed by a Railway Stock, Railway Stock Routing Problem determine a sequence of train while satisfying turnaround time and maintenance restrictions. The objective is to minimize the Railway Stock during a week and each day simultaneously. And we prove that Railway Stock Routing Problem with maintenance restrictions is NP-hard. In this paper, we present two stage approaches that solve the Railway Stock Routing Problem in a reasonable time. In first stage we relax maintenance restrictions and formulate as a Min-cost-flow problem. Then, in the second stage, we attempt to satisfy maintenance restrictions using ours heuristic algorithm. We show the computational result of applying to an actual train schedule data.

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컨테이너 반출예약제 기대효과의 계량적분석 (Numerical Analysis of Delivery Reservation Effect)

  • 김우선;최용석;하태영
    • 한국항해항만학회:학술대회논문집
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    • pp.237-241
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    • 2003
  • 컨테이너터미널의 경쟁력을 향상시키기 위해서 만성적 부족상태에 있는 국내 컨테이너 터미널의 야드 효율성을 높이고, 터미널 생산성을 향상시킬 수 있는 반출예약제에 대한 기본적인 개념과 기존 터미널에 적용 시 기대효과를 연구

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DB 수정방식에 따른 지능망 시스템의 성능추이분석 (Performance Trend Analysis For IN System Based On DB Updating Method)

  • 노용덕
    • 한국시뮬레이션학회논문지
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    • v.11 no.2
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    • pp.45-53
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    • 2002
  • The main idea behind the Intelligent Networks(IN) concept is the separation of switching functionality from the service control, in order to meet various service requirements of subscribers and development of new services in time. In (N+1) type Intelligent Network with FEP-BEP framwork, each SCP-BEP system maintains its own subscibers' database respectively. In this case, DB updating operations at each SCP-BEP should be peformed concurrently such that DB updating method could affect the overall system performance. Moreover, it is not easy to predict the current system capacity to satisfy the future IN subscribers' service needs. In this paper, we discuss how much DB updating method affects the performance trends of (N+1) type Intelligent Network with FEP-BEP system by means of the simulation technique as the number of calls increase. The average turnaround time is used as a system performance measure.

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Architectural Design of Terminal Operating System for a Container Terminal Based on a New Concept

  • Singgih, Ivan Kristianto;Jin, Xuefeng;Hong, Soondo;Kim, Kap Hwan
    • Industrial Engineering and Management Systems
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    • v.15 no.3
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    • pp.278-288
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    • 2016
  • Automation ensures accurate and well-organized container transportation in container terminals. This paper addresses operational issues such as equipment scheduling and the coordination between various pieces of equipment in a rail-based automated container terminal. Containers are relayed using multiple types of equipment from road trucks to a vessel and vice versa. Therefore, handshaking is required during a container transfer between different pieces of equipment. Synchronization between the schedules of all the equipment is important to reduce equipment waiting times and the time required for transporting containers, which results in a short turnaround time for a vessel. This paper proposes an integrated control system with the objective of synchronizing the operations of different types of equipment, provides a list of decisions to be made by the control module of each type of equipment, and shows all the required information transfers between control modules. A scheme for the integrated scheduling of multiple types of equipment is proposed. The decisions made by each control module in a real-time fashion are listed with detailed explanations, and the information transfer between managers in a real-time situation at the proposed terminal is described.