%0 Journal Article
%T NIDE: A Novel Improved Differential Evolution for Construction Project Crashing Optimization
%A Nhat-Duc Hoang
%J Journal of Construction Engineering
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/136397
%X In the field of construction management, project crashing is an approach to shortening the project duration by reducing the duration of several critical project activities to less than their normal activity duration. The goal of crashing is to shorten the project duration while minimizing the crashing cost. In this research, a novel method for construction project crashing is proposed. The method is named as novel improved differential evolution (NIDE). The proposed NIDE is developed by an integration of the differential evolution (DE) and a new probabilistic similarity-based selection operator (PSSO) that aims at improving the DE¡¯s selection process. The PSSO has the role as a scheme for preserving the population diversity and fending off the premature convergence. The experimental result has demonstrated that the newly established NIDE can successfully escape from local optima and achieve a significantly better optimization performance. 1. Introduction In the field of construction management, a construction project can be typically defined as a set of individual activities with their technical/managerial constraints. The nature of construction projects, which is characterized by constant changes in the environment, pressures to maintain schedules/costs with increasingly complex construction techniques, makes the task of project management a significant challenge [1]. Due to the complexity of construction projects, schedule management is proved to be very challenging [2]. Therefore, schedule overrun is not unusual in the construction field. Moreover, there can be a great motivation for the construction contractor and the project owner to reduce the project time [3]. The reason is that as a project progresses, it consumes indirect costs, consisting of the cost of facilities, equipment, and machinery, interest on investment, utilities, labor, and the loss of skills and labor of the project team who are not working at their regular jobs [4]. There also may be severe financial penalties for not completing a project on time; many construction and government contracts have penalty clauses for exceeding the project completion date. In addition, the project owner may desire to reduce the completion time in order to put the facility into operation sooner. In practice, to shorten the project schedule, the manager may accelerate some of the activities at an additional cost, that is, by allocating more or better resources, such as labor and equipment. Minimizing the sum of activity direct costs while meeting a specified deadline is of practical need and this has
%U http://www.hindawi.com/journals/jcen/2014/136397/