A plant construction project always involves lots of activities. Precise information about the activities duration is unfortunately unavailable due to the uncertain resources capacity. The fuzzy program evaluation and review technique (PERT) has been widely applied to solve the fuzzy project scheduling problem. This paper presents an extended fuzzy PERT approach with four major improvement aspects to support the construction project scheduling management: 1) Evaluate operation fuzzy times based on available working volumes, resources quantity and fuzzy capacity of resources, 2) Adopting a maximal i levelcut method to compare the fuzzy precedent activities times to determine the reasonable earliest starting times of each activity, 3) Using fuzzy algebra method instead of fuzzy subtraction method to compute the fuzzy latest starting times and 4) Developing a project scheduling risk index (PSRI) to assist the decision maker to evaluate the project scheduling risk. Simulations experiments are conducted and demonstrated satisfactory results.
The plant construction project scheduling is not easy to handle due to various uncertain factors. For example the resources capacity is an important uncertain. Its uncertainty will impact the project scheduling. In industrial practice the decision makers usually use crisp value to estimate the project time while they bid a potential project. But when they get the orders or contracts, frequently they can’t complete construction on time and the resulting cost always exceeds original expectations. How to evaluate the construction project scheduling risk is an important problem. Fuzzy PERT (program evaluation review techniques) has been widely used to describe the uncertain task durations and scheduling of real industrial practice in project management. There are vast literatures devoted to research about the fuzzy PERT theories and applications. Mon et al. (1995) applied fuzzy distributions on project management to analysis schedule and cost. Chanas, S. & Zielinski, P. (2001) analysis critical patch in the network with fuzzy activity times. Dubois et al. (2003a) studied on latest starting times and floats in activity networks with illknown durations. Dubois et al. (2003b) also planed fuzzy scheduling with incomplete knowledge. Slyetsov et al. (2003) researched the fuzzy temporal characteristics of operations for project management based on the network models. Wang (1999) developed a fuzzy set approach to schedule product development projects with temporal information. Wang (2002) used a fuzzy project scheduling approach to minimize schedule risk for product development. Wang (2004) applied a genetic algorithm for solving the problem under the objective of maximizing the worst case scheduling. Nezhad et al. (2008) proposed a fuzzy number maximum operator approximation and its application in fuzzy shop scheduling.
Publisher : JIEM
By : Hsian Jong Hsiau ; Chun Wei R.Lin
File Information: English Language/ 17 Page / size: 1,355 KB
سال : 2009
ناشر : JIEM
کاری از : Hsian Jong Hsiau ; Chun Wei R.Lin
اطلاعات فایل : زبان انگلیسی / 17 صفحه / حجم : KB 1,355
لینک دانلود : روی همین لینک کلیک کنید