• 제목/요약/키워드: Queue Capacity

검색결과 98건 처리시간 0.026초

DISCRETE-TIME QUEUE WITH VARIABLE SERVICE CAPACITY

  • LEE YUTAE
    • 대한수학회지
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    • 제42권3호
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    • pp.517-527
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    • 2005
  • This paper considers a discrete-time queueing system with variable service capacity. Using the supplementary variable method and the generating function technique, we compute the joint probability distribution of queue length and remaining service time at an arbitrary slot boundary, and also compute the distribution of the queue length at a departure time.

A diffusion approximation for time-dependent queue size distribution for M/G/m/N system

  • Park, Bong-Dae;Shin, Yang-Woo
    • 대한수학회지
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    • 제32권2호
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    • pp.211-236
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    • 1995
  • The purpose of this paper is to provide a transient diffusion approximation of queue size distribution for M/G/m/N system. The M/G/m/N system can be expressed as follows. The interarrival times of customers are exponential and the service times of customers have general distribution. The system can hold at most a total of N customers (including the customers in service) and any further arriving customers will be refused entry to the system and will depart immediately without service. The queueing system with finite capacity is more practical model than queueing system with infinite capacity. For example, in the design of a computer system one of the important problems is how much capacity is required for a buffer memory. It its capacity is too little, then overflow of customers (jobs) occurs frequently in heavy traffic and the performance of system deteriorates rapidly. On the other hand, if its capacity is too large, then most buffer memories remain unused.

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MAP/G/1/K QUEUE WITH MULTIPLE THRESHOLDS ON BUFFER

  • Choi, Doo-Il
    • 대한수학회논문집
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    • 제14권3호
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    • pp.611-625
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    • 1999
  • We consider ΜΑΡ/G/ 1 finite capacity queue with mul-tiple thresholds on buffer. The arrival of customers follows a Markov-ian arrival process(MAP). The service time of a customer depends on the queue length at service initiation of the customer. By using the embeded Markov chain method and the supplementary variable method, we obtain the queue length distribution ar departure epochs and at arbitrary epochs. This gives the loss probability and the mean waiting time by Little's law. We also give a simple numerical examples to apply the overload control in packetized networks.

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도로터널의 제연용량 산정을 위한 정체차량대수 산정기법에 관한 연구 - 정체길이를 중심으로 (A study on the calculation method for the number of vehicles in queue to determine the fire ventilation capacity in road tunnels - forced on the effect of queue length)

  • 유용호;김효규;류지오
    • 한국터널지하공간학회 논문집
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    • 제18권1호
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    • pp.41-52
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    • 2016
  • 터널 화재시 정체차량에 의한 정체길이가 터널연장을 초과할 경우, 환기저항의 증가에 따른 제연설비 용량의 증가가 발생하게 된다. 그러나 현행 방재지침에는 정체길이에 대한 정의가 없기 때문에 합리적 산출식의 제시가 필요하다. 본 연구에서는 터널 화재시 정체차량 대수에 의한 정체길이의 산정식을 제시하고, 터널연장별 적용성 분석을 수행하였다. 일반적인 터널의 경우, 화재시 정체길이의 과도한 적용을 방지하기 위해서는 터널연장 1,200 m 까지는 정체길이와 터널연장과의 상호비교가 필요한 것으로 분석되었고, 모델터널에 대한 적용성 평가결과 제연용 제트팬의 절감효과가 있는 것으로 분석되었다. 더불어 정체길이의 판별여부를 대형차혼입률과 터널연장의 관계로 설명할 수 있는 정량화 선도를 제시하였다. 결과적으로 제연설비 용량결정시, 정체차량에 의한 정체길이가 터널연장을 초과하는 경우에는 터널연장을 초과하는 차량대수는 차량에 의한 환기저항 산정에서 제외하는 것이 타당한 것으로 분석된다.

A Note on the Relationships among the Queue Lengths at Various Epochs of a Queue with BMAP Arrivals

  • Kim, Nam K;Chae, Kyung C;Lee, Ho W
    • Management Science and Financial Engineering
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    • 제9권2호
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    • pp.1-12
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    • 2003
  • For a stationary queue with BMAP arrivals, Takine and Takahashi [8] present a relationship between the queue length distributions at a random epoch and at a departure epoch by using the rate conservation law of Miyazawa [6]. In this note, we derive the same relationship by using the elementary balance equation, ‘rate-in = rate-out’. Along the same lines, we additionally derive relationships between the queue length distributions at a random epoch and at an arrival epoch. All these relationships hold for a broad class of finite-as well as infinite-capacity queues with BMAP arrivals.

컴퓨터 통합생산을 위한 토큰버스 네트워크의 성능관리 (Performance Management of Token Bus Networks for Computer Integrated Manufacturing)

  • 이상호;이석
    • 한국정밀공학회지
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    • 제13권6호
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    • pp.152-160
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    • 1996
  • This paper focuses on development and evaluation of a performance management algorithm for IEEE 802.4 token bus networks to serve large-scale integrated manufacturing systems. Such factory automation networks have to satisfy delay constraints imposed on time-critical messages while maintaining as much network capacity as possible for non-time-critical messages. This paper presents a network performance manager that adjusts queue capacity as well as timers by using a set of fuzzy rules and fuzzy inference mechanism. The efficacy of the performance management has been demonstrated by a series of simulation experiments.

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상관적인 Batch 입력을 갖는 2-노드 Tandem 구조의 이산시간 대기 네트워크의 근사적 분석 (Approximate Analysis of the Discrete-time 2-Node Tandem Queueing Network with a Correlated Batch Input Traffic)

  • 박두영
    • 공학논문집
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    • 제1권1호
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    • pp.31-40
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    • 1997
  • ATM망의 모델링에서 발생되어지는 D-BMAP/Geo/1/K queue의 departure 프로세스를 k-state MMBP로 특성화하는 근사화방법을 제시하고, 그 근사화방법과 decomposition algorithm을 이용하여 셀손실을 갖는 tandem 구조의 한정용량 대기 네트워크를 분석하였다.

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미시적 시뮬레이션을 통한 PRT 정류장 용량분석 (Analysis of PRT Station Capacity based on Micro Simulation)

  • 김백현;정락교;황현철
    • 전기학회논문지
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    • 제60권12호
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    • pp.2254-2259
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    • 2011
  • The introduction of Personal Rapid Transit (PRT) has been widely discussed in the Korean transportation research field. However, there is no robust criterion to derive the throughput of cars and passengers at PRT stations, which plays a primary role in determining the overall capacity of PRT systems. The present study provided a methodology to rigorously compute the capacity for simple-serial PRT stations with a single platform, considering three decisive factors, i.e., the demand level of incoming cars and outgoing passengers, the station structure, and the operation strategy. A micro-level simulator was developed for the analysis of station capacity. And, by using this, station capacities were presented for various combinations of the decisive factors. In particular, the relationship between capacity and station structure was investigated in detail. Station structure is represented by the numbers of platform berths, input queue berths, and output queue berths. Moreover, both waive rate and waiting time, which represent the level of passenger service, were taken into account when the station throughput was computed.

신호교차로 분석시 초기대기행렬이 총지체도에 미치는 영향에 관한 연구 (The Study on Effects Caused by the Initial Queue to the Total Delay Estimation in Analyzing Signalized Intersection)

  • 박순표;김기혁
    • 대한토목학회논문집
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    • 제29권5D호
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    • pp.563-570
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    • 2009
  • 본 연구는 신호교차로 분석시 추가지체 산정을 위하여 적용하는 초기 대기차량이 총 지체도에 얼마나 영향을 미치는지 분석하기 위한 목적으로 실시하였다. 평균교차로 지체시간을 측정하기위하여 통과차량과 대기행렬이 측정되었다. 분석결과, 시험차량의 평균 지체도가 60초/대 미만 일 경우에는 세가지 지체도 산정방법이 모두 유사한 것으로 분석되었으나, 60~70초/대는 초기 대기차량을 적용한 지체도만 시험차량의 평균지체도와 유사한 것으로 분석되었다.