BACKGROUND Ventilator-associated pneumonia (VAP) is a common side effect in patients who receive intravenous sedation infusion. In routine care, after starting sedation infusion for patients who receive mechanical ventilation, interruption of sedation starts without protocol. This study aimed to evaluate the effect of daily sedation vacation protocol on the incidence of VAP in mechanically vent...

the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract We consider an M [x] /G/1 queue with two types of service subject to random breakdowns having multiple server vacation, where the customers arrive to the system in batches of variable size. We assume that a single server p...

Consider a single server retrial queueing system with preemptive priority service and single working vacation in which two types of customers arrive in a Poisson process with arrival rates λ1 for low and λ2 for high priority customers. We assume that regular service times follow an exponential distribution with parameters μ1 and μ2 correspondingly. The retrial is introduced for low priority cus...

In this contribution we investigate discrete-time queueing systems with vacations. A framework is constructed that allows for studying numerous different vacation systems, including a.o. classical vacation systems like the exhaustive and limited vacation systems as well as queueing systems with service interruptions. Using a probability generating functions approach, we obtain steady-state perf...

This paper refers to some closed two-stage queueing systems with state-dcpendent vacation policy. By means of the markovian rcnewal process and the stochastic decomposition formulas of the quantities in equilibrium for M/Gjl vacation models, we derive both stationary distributions of the queue length and the cyclic time for the closed state-dependcnt vacation model. We try to so!\'e the problem...

Consider an M/M/1 queueing system with server vacations where the server is turned oo as soon as the queue gets empty. We assume that the vacation durations form a sequence of i.i.d. random variables with exponential distribution. At the end of a vacation period, the server may either be turned on if the queue is non empty or take another vacation. The following costs are incurred: a holding co...

This paper deals with the transient analysis of batch arrival retrial queueing system with general retrial times, priority service, balking, second optional service, Bernoulli vacation, extended vacation, breakdown, delayed repair and stand by server. Here we assume that customers arrive in batches according to compound Poisson processes, where the blocked customers either with probability p jo...

This paper is devoted to the study of an M/G/1 queue with a particular vacation discipline. The server is due to take a vacation as soon as it has served exactly N customers since the end of the previous vacation. N may be either a constant or a random variable. If the system becomes empty before the server has served N customers, then it stays idle until the next customer arrival. Such a vacat...

This paper treats two-threshold policies for an M/G/1 queue with two types of generally distributed random vacations: type 1 (long) and type 2 (short) vacations. Upon returning from a vacation, the server observes the queue length. If this is less than the lower threshold, the server takes a type 1 vacation; if it is between the two thresholds, the server takes a type 2 vacation; and if it is a...