Contrary to traditional belief, we show in this paper, that for distributed systems non-preemptive scheduling can perform better than preemptive scheduling in the worst case in terms of task schedulability, under certain circumstances. We derive a worst-case delay bound for tasks scheduled using non-preemptive scheduling in a distributed system, where the task flow paths form a directed acyclic...

nowadays, scheduling problems have a considerable application in production and service systems. in this paper, we consider the scheduling of n jobs on a single machine assuming no machine idleness, non-preemptive jobs and equal process times. in many of previous researches, because of the delivery dalays and holding costs, earliness and tardiness penalties emerge in the form of linear combinat...

There has been a dramatic change in the philosophy of treatment of patients who are critically ill with neurologic diseases. New therapies and monitoring techniques have shifted the focus of treatment from the reactive strategy that was the hallmark of both neurology and neurosurgery in the past, to an aggressive, preemptive strategy. In this review, we will focus on current controversies and r...

This paper considers three variants of last-come first-served (LCFS) preemptive service single-server queues, where customers are served under the LCFS preemptive resume (LCFS-PR), preemptive repeat-different (LCFS-PD), and preemptive repeat-identical (LCFS-PI) disciplines, respectively. These LCFS queues are fed by multiple batch Markovian arrival streams. Service times of customers from each ...

Recent developments in cognitive linguistics have highlighted the importance and the ubiquity of metaphors in language. Their effect has been instrumental in making significant headway into the pedagogical practice and design of teaching materials. The current study was carried out to explore the efficacy of focus-on-form (FonF) and focus-on-forms (FonFs) instructions on learning metaphorical l...

Background and Objective: Post-operative nausea and vomiting (PONV) is a common adverse effect of the anesthesia in laparoscopic surgery. Ondansetron has been used for prevention and treatment of the PONV. The purpose of the present study was to compare the effects of preemptive and preventive intravenous ondansetron on PONV in patients undergoing diagnostic gynecologic laparoscopy. Materials &...