Queues with slow servers and impatient customers
Uri Yechiali2010, European Journal of Operational Research
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Abstract
We study M=M=c queues (c ¼ 1, 1 < c < 1 and c ¼ 1Þ in a 2-phase (fast and slow) Markovian random environment, with impatient customers. The system resides in the fast phase (phase 1) an exponentially distributed random time with parameter g and the arrival and service rates are k and l, respectively. The corresponding parameters for the slow phase (phase 0) are c, k 0 , and l 0 ð6 lÞ. When in the slow phase, customers become impatient. That is, each customer, upon arrival, activates an individual timer, exponentially distributed with parameter n. If the system does not change its environment from 0 to 1 before the customer's timer expires, the customer abandons the queue never to return.
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