Browsing by Author "Ke, JC"

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Maximum likelihood estimates and confidence intervals of an M/M/R queue with heterogeneous servers
(2006-05-01)
Wang, TY
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Ke, JC
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Wang, KH
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Ho, SC
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工業工程與管理學系
This paper studies maximum likelihood estimates as well as confidence intervals of an M/M/R queue with heterogeneous servers under steady-state conditions. We derive the maximum likelihood estimates of the mean arrival rate and the three unequal mean service rates for an M/M/3 queue with heterogeneous servers, and then extend the results to an M/M/R queue with heterogeneous servers. We also develop the confidence interval formula for the parameter rho, the probability of empty system P-0, and the expected number of customers in the system E[N], of an M/M/R queue with heterogeneous servers.
Sensitivity analysis of the optimal management policy for a queuing system with a removable and non-reliable server
(2004-03-01)
Pearn, WL
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Ke, JC
;
Chang, YC
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工業工程與管理學系
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Department of Industrial Engineering and Management
The management policy of an M/G/1 queue with a single removable and non-reliable server is considered. The decision-maker can turn the single server on at any arrival epoch or off at any service completion. It is assumed that the server breaks down according to a Poisson process and the repair time has a general distribution. Arrivals form a Poisson process and service times are generally distributed. In this paper, we consider a practical problem applying such a model. We use the analytic results of the queueing model and apply an efficient Matlab program to calculate the optimal threshold of management policy and some system characteristics. Analytical results for sensitivity analysis are obtained. We carry out extensive numerical computations for illustration purposes. An application example is presented to display how the Matlab program could be used. The research is useful to the analyst for making reliable decisions to manage the referred queueing system. (C) 2003 Elsevier Ltd. All rights reserved.