• 제목/요약/키워드: queueing analysis

검색결과 340건 처리시간 0.027초

대기행렬이론을 활용한 의료서비스 환자 대기환경 평가 (Evaluation of Patients' Queue Environment on Medical Service Using Queueing Theory)

  • 여현진;박원숙;유명철;박상찬;이상철
    • 품질경영학회지
    • /
    • 제42권1호
    • /
    • pp.71-79
    • /
    • 2014
  • Purpose: The purpose of this study is to develop the methods for evaluating patients' queue environment using decision tree and queueing theory. Methods: This study uses CHAID decision tree and M/G/1 queueing theory to estimate pain point and patients waiting time for medical service. This study translates hospital physical data process to logical process to adapt queueing theory. Results: This study indicates that three nodes of the system has predictable problem with patients waiting time and can be improved by relocating patients to other nodes. Conclusion: This study finds out three seek points of the hospital through decision tree analysis and substitution nodes through the queueing theory. Revealing the hospital patients' queue environment, this study has several limitations such as lack of various case and factors.

통신망 트래픽 제어를 위한 BMAP/M/N/0 대기행렬모형 분석 (Analysis of BMAP/M/N/0 Queueing System for Telecommunication Network Traffic Control)

  • 이석준;김제숭
    • 산업경영시스템학회지
    • /
    • 제30권4호
    • /
    • pp.39-45
    • /
    • 2007
  • The BMAP/M/N/0 queueing system operating in Markovian random environment is investigated. The stationary distribution of the system is derived. Loss probability and other performance measures of the system also are calculated. Numerical experiments which show the necessity of taking into account the influence of random environment and correlation in input flow are presented.

QUEUEING ANALYSIS OF DYNAMIC RATE LEAKY BUCKET SCHEME WITH MARKOVIAN ARRIVAL PROCESS

  • Choi, Doo-Il;Kim, Hyun-Sook;Sur, Uk-Hwan
    • Journal of applied mathematics & informatics
    • /
    • 제6권2호
    • /
    • pp.553-568
    • /
    • 1999
  • This paper is of concern to queueing analysis of the dynamic rate leaky bucket(LB) scheme in which the token generation interval changes according to the buffer state at a token generation epoch. Cell arrivals are assumed to follow a Markovian arrival process (MAP) which is weakly dense in the class of the stationary point processes. By using the embedded Markov chain method we obtain the probability distribution of the system state at a token generation epoch and an arbitrary time. Some simple numerical examples also are provided to show the effects of the proposed LB scheme.

Queueing Network을 이용한 PC 통신 시스템 분석 (Analysis of the PC Communication System using Queueing Network)

  • 오근태;김준홍
    • 산업경영시스템학회지
    • /
    • 제17권32호
    • /
    • pp.53-62
    • /
    • 1994
  • This paper deals with the analysis of the PC communication service system performance which will be installed as a gateway between PSTN and PSDN. Firstly, we classify the data traffic pattern into interactive, conversational, and file transfer type from the actual statistics. Secondly, we model the system structure as a closed queueing network model with multiservers and multiple customer classes and derive the analytic method to be able to measure the system performance using Mean Value Analysis. Finally, the simulation results indicate that the analytic method obtained is a good approximation method to measure the system performance of the PC communication service system as a gateway between PSTN and PSDN.

  • PDF

QUEUEING ANALYSIS FOR TRAFFIC CONTROL WITH COMBINED CONTROL OF DYNAMIC MMPP ARRIVALS AND TOKEN RATES

  • Choi, Doo Il
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • 제17권2호
    • /
    • pp.103-113
    • /
    • 2013
  • We analyze the queueing model for leaky bucket (LB) scheme with dynamic arrivals and token rates. In other words, in our LB scheme the arrivals and token rates are changed according to the buffer occupancy. In telecommunication networks, the LB scheme has been used as a policing function to prevent congestion. By considering bursty and correlated properties of input traffic, the arrivals are assumed to follow a Markov-modulated Poisson process (MMPP). We derive the distribution of system state, and obtain the loss probability and the mean waiting time. The analysis is done by using the embedded Markov chain and supplementary variable method. We also present some numerical examples to show the effect of our proposed model.

퍼터베이션 분석을 이용한 대기행렬 네트워크의 최적화 (Optimization of Queueing Network by Perturbation Analysis)

  • 권치명
    • 한국시뮬레이션학회논문지
    • /
    • 제9권2호
    • /
    • pp.89-102
    • /
    • 2000
  • In this paper, we consider an optimal allocation of constant service efforts in queueing network to maximize the system throughput. For this purpose, using the perturbation analysis, we apply a stochastic optimization algorithm to two types of queueing systems. Our simulation results indicate that the estimates obtained from a stochastic optimization algorithm for a two-tandem queuing network are very accurate, and those for closed loop manufacturing system are a little apart from the known optimal allocation. We find that as simulation time increases for obtaining a new gradient (performance measure with respect to decision variables) by perturbation algorithm, the estimates tend to be more stable. Thus, we consider that it would be more desirable to have more accurate sensitivity of performance measure by enlarging simulation time rather than more searching steps with less accurate sensitivity. We realize that more experiments on various types of systems are needed to identify such a relationship with regards to stopping rule, the size of moving step, and updating period for sensitivity.

  • PDF

ANALYSIS OF QUEUEING MODEL WITH PRIORITY SCHEDULING BY SUPPLEMENTARY VARIABLE METHOD

  • Choi, Doo Il
    • Journal of applied mathematics & informatics
    • /
    • 제31권1_2호
    • /
    • pp.147-154
    • /
    • 2013
  • We analyze queueing model with priority scheduling by supplementary variable method. Customers are classified into two types (type-1 and type-2 ) according to their characteristics. Customers of each type arrive by independent Poisson processes, and all customers regardless of type have same general service time. The service order of each type is determined by the queue length of type-1 buffer. If the queue length of type-1 customer exceeds a threshold L, the service priority is given to the type-1 customer. Otherwise, the service priority is given to type-2 customer. Method of supplementary variable by remaining service time gives us information for queue length of two buffers. That is, we derive the differential difference equations for our queueing system. We obtain joint probability generating function for two queue lengths and the remaining service time. Also, the mean queue length of each buffer is derived.

용량제한을 갖는 중첩형 대기행렬 네트워크의 성능 범위분석 (A Boundness Analysis of Performance on the Nested Queueing Network with Population Constraint)

  • 이영
    • 한국정보과학회논문지:시스템및이론
    • /
    • 제36권4호
    • /
    • pp.239-246
    • /
    • 2009
  • 각 계층 네트워크가 세마포에 의하여 용량제한을 갖는 중첩형 대기행렬 네트워크의 평균대기시간에 관하여 연구하였다. 중첩형 대기행렬 네트워크는 고객의 대기시간 관점에서 보다 간단한 대기행렬 네트워크로 변환될 수 있다. 이러한 중첩형 대기행렬 네트워크의 가장 중요한 특성은 하위계층의 흐름이 상위 계층의 상태에 의존적이며, 제한을 받는다는 것이다. 이러한 형태의 대기행렬 네트워크는 성능분석을 정확히 할 수 없기 때문에, 변환된 중첩형 대기행렬 네트워크를 이용하여 평균대기시간에 대한 하한과 상한을 분석하고자 한다. 모의실험에 관한 측정은 도착분포가 단계형태 분포로서 포아송, 얼랑 그리고 초지수분포에 관하여 조사하였다. 이렇게 구한 범위는 추후에 좀 더 근접한 근사치를 구하는데 이용할 수 있다.

대학도서관의 복본수 결정기법에 관한 연구

  • 양재한
    • 한국도서관정보학회지
    • /
    • 제13권
    • /
    • pp.131-166
    • /
    • 1986
  • This study is designed to review the methods of duplicate copies decision making in the academic library. In this thesis, I surveyed queueing & markov model, statistical model, and simulation model. The contents of the study can be summarized as follows: 1) Queueing and markov model is used for one of duplicate copies decision-making methods. This model was suggested by Leimkuler, Morse, and Chen, etc. Leimkuler proposed growth model, storage model, and availability model through using system analysis method. Queueing theory is a n.0, pplied to Leimkuler's availability model. Morse ad Chen a n.0, pplied queueing and markov model to their theory. They used queueing theory for measuring satisfaction level and Markov model for predicting user demand. 2) Another model of duplicate copies decision-making methods is statistical model. This model is suggested by Grant and Sohn, Jung Pyo. Grant suggested a model with a formula to satisfy the user demand more than 95%, Sohn, Jung Pyo suggested a model with two formulars: one for duplicate copies decision-making by using standard deviation and the other for duplicate copies predicting by using coefficient of variation. 3) Simulation model is used for one of duplicate copies decision-making methods. This model is suggested by Buckland and Arms. Buckland considered both loan period and duplicate copies simultaneously in his simulation model. Arms suggested computer-simulation model as one of duplicate copies decision-making methods. These methods can help improve the efficiency of collection development and solve some problems (space, staff, budget, etc, ) of Korean academic libraries today.

  • PDF

서버상태의존 도착률을 갖는 M/G/l 모형의 최적 제어정책 (Optimal N-Policy of M/G/1 with Server Set-up Time under Heterogeneous Arrival Rates)

  • 백승진;허선
    • 산업경영시스템학회지
    • /
    • 제20권43호
    • /
    • pp.153-162
    • /
    • 1997
  • M/G/1 queueing system is one of the most widely used one to model the real system. When operating a real systems, since it often takes cost, some control policies that change the operation scheme are adopted. In particular, the N-policy is the most popular among many control policies. Almost all researches on queueing system are based on the assumption that the arrival rates of customers into the queueing system is constant, In this paper, we consider the M/G/1 queueing system whose arrival rate varies according to the servers status : idle, set-up and busy states. For this study, we construct the steady state equations of queue lengths by means of the supplementary variable method, and derive the PGF(probability generating function) of them. The L-S-T(Laplace Stieltjes transform) of waiting time and average waiting time are also presented. We also develop an algorithm to find the optimal N-value from which the server starts his set-up. An analysis on the performance measures to minimize total operation cost of queueing system is included. We finally investigate the behavior of system operation cost as the optimal N and arrival rate change by a numerical study.

  • PDF