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 &...

We investigate the problem of scheduling the maintenance of edges in a network, motivated by the goal of minimizing outages in transportation or telecommunication networks. We focus on maintaining connectivity between two nodes over time; for the special case of path networks, this is related to the problem of minimizing the busy time of machines. We show that the problem can be solved in polyn...

In the recent years, constraint programming has been applied to a wide variety of academic and industrial non-preemptive scheduling problems, i.e., problems in which activities cannot be interrupted. In comparison, preemptive scheduling problems have received almost no attention from both the Operations Research and the Artificial Intelligence community (see, for example, (Demeulemeester, 1992)...

BACKGROUND Information to guide the timing of a second kidney transplantation is limited. METHODS We compared outcomes of 3509 preemptive and 14,075 nonpreemptive second kidney transplant recipients in the U.S. Renal Data System between 1995 and 2007. RESULTS Preemptive recipients had less acute rejection (12% vs. 16%; P<0.0001) and delayed graft function (8% vs. 23%; P<0.0001). Preemptive ...

We design an algorithm of the best possible competitive ratio for preemptive and non-preemptive scheduling of unit size jobs with rejection on three identical machines. The algorithm does not use preemption even for the preemptive variant, and it has the interesting feature that one of its parameters is not fixed in advance, and it is defined based on the properties of the first input job havin...

This paper presents formulas for calculating waiting time for customers in a queue with combined preemptive and head-ofline (nonpreemptive) priority scheduling disciplines and describes the reasoning behind them. This work has been applied in the development of programmable terminal control units. Introduction The development of programmable terminal control units has created the need for a new...

in this paper, we try and valuate preemption rights by modifying the black-scholes model, which is widely used to valuate options and other derivatives. here we first present the basics of the black-scholes model and then we discus modification of the model to be fit for preemption right valuation. at the end, we valuate four of the preemptive rights using the proposed model