In this research, both resource allocation and reactive resource allocation problems in multi-server dynamic PERT networks are analytically modeled, where new projects are expected to arrive according to a Poisson process, and activity durations are also known as independent random variables with exponential distributions. Such system is represented as a queuing network, where multi servers at ...

agricultural mechanization project must be identified in a short time frame to do a certain way; otherwise, cost is not the time to come and will also result in reduced yield. to avoid these costs in farming systems is necessary in any region that agricultural mechanization projects are and scheduling and planning as well as scientific until activities included in the project to fruition are do...

This paper deals with the fundamental problem of estimating the distribution function (df) of the duration of the longest path in the stochastic activity network such as PERT network. First a technique is introduced to reduce variance in Conditional Monte Carlo Sampling (CMCS). Second, based on this technique a new procedure is developed for CMCS. Third, a combined approach of simulation and ap...

Abstract : In this paper , we apply the stochastic dynamic programming to approximate the mean project completion time in dynamic Markov PERT networks. It is assumed that the activity durations are independent random variables with exponential distributions, but some social and economical problems influence the mean of activity durations. It is also assumed that the social problems evolve in ac...

In this paper, a new method for developing a lower bound on exact completion time distribution function of stochastic PERT networks is provided that is based on simplifying the structure of this type of network. The designed mechanism simplifies network structure by arc duplication so that network distribution function can be calculated only with convolution and multiplication. The selection of...

This investigation presents a heuristic method for consumable resource allocation problem in multi-class dynamic Project Evaluation and Review Technique (PERT) networks, where new projects from different classes (types) arrive to system according to independent Poisson processes with different arrival rates. Each activity of any project is operated at a devoted service station located in a node...

Mailing address: Iseu Gus • Avenida Princesa Isabel, 395 – 90620-001 – Porto Alegre, RS Brazil E-mail: [email protected] Manuscript received June 7, 2006; revised manuscript received September 21, 2006; accepted October 5, 2006. For centuries medicine progressed very slowly1, and in the past fifty years its development has been “blindingly fast” and difficult to keep up with, and made the means o...

Considering the network structure is one of the new approaches in studying stochastic PERT networks (SPN). In this paper, planar networks are studied as a special class of networks. Two structural reducible mechanisms titled arc contraction and deletion are developed to convert any planar network to a series-parallel network structure.&#10In series-parallel SPN, the completion time distribution...

OBJECTIVES Pancreatic enzyme replacement therapy (PERT) remains a backbone in the nutritional treatment of cystic fibrosis. Currently, there is a lack of an evidence-based tool that allows dose adjustment. To date, no studies have found an association between PERT dose and fat absorption. Therefore, the aim of the study was to assess the influence of both the PERT dose and the variability in th...