Authors: Chuan Kian Pang, Noor Ajian Mohd-Lair, Yi Sheng Chua
Abstract: An air-conditioning and mechanical ventilation (ACMV) construction project involved many interrelated construction activities with varying durations and multiple dependencies. This paper focuses on the development of a best possible project planning and scheduling technique that can help the project manager to manage and complete the ACMV project in optimal time. The program evaluation and review technique (PERT) is used in this research. The PERT technique helps to determine the probabilities of various stages of the project by specified deadlines and identify the activities on the critical path that have high potential for causing delays in the project completion time. The completion times of 72, 76, 79, and 80 weeks were taken for the PERT analysis. Deadline of 72 weeks is the contractual period of the ACMV project as specified in the contract. Completion time of 76 weeks is the critical path of the project as analyzed by the PERT technique. The deadline of 79 weeks is the proposed completion time for the ACMV project whereas 80 weeks are the actual completion date of the project. The PERT analysis revealed that the project completion time of 72 weeks, which is as stated in the contractual completion time, yielded the probability of completion of 2.67% only. This analysis shows that the contractual period is impossible to be achieved and it is an unrealistic time setting. Further negotiation is required including changing or extending of the contractual completion time. The other completion times are able to be achieved but the company may need to face the high penalty costs due to the delays in completion time.
266
Authors: Lu Cheng, Guang Rui Liao, Zhen Yuan Liu
Abstract: In this paper, we address the project scheduling problem with the aim of making the best use of people's talents while minimizing project makespan and the amount of wasted resources. The purpose of proposing this problem is to assist project managers to improve the quality of products and save cost. To solve this problem, we also proposed an immune genetic algorithm (IGA). This algorithm designs feasible schedule for projects. By designing computational experiments carried out on j60 from PSPLIB, we evaluate the performance of proposed IGA as well as compare it with traditional GA. It turns out that proposed IGA performs much better in the aspect of improving diversity and minimizing makespan, which provides more diverse and effective solutions.
1268
Authors: Yan Li, Zhi Run Xiao
Abstract: The problem of multi-skilled project scheduling (MSPSP) is a complex problem of task scheduling and resource assignment that comes up in the daily management of many software company. In this paper we present a constraint programming (CP) approach for the MSPSP. We extend the project scheduling literature by developing a project scheduling model that accounts for differing skills among workers. The computational results for the MSPSP show that the constraint programming approach increases the performance of the model solving processes. The results for the MSPSP is effective in solving the proposed problem.
265
Authors: Yan Li, Zhi Run Xiao, Wen Qing Dou, Ying Yang
Abstract: The Skilled Workforce Project Scheduling Problem (SWPSP) is a complex problem of task scheduling and resource assignment that comes up in the daily management of many company Service Centers. In this paper we present a constraint programming (CP) approach for the SWPSP. We extend the project scheduling literature by developing a project scheduling model that accounts for differing skills among workers. The computational results for the SWPSP show that the constraint programming approach increases the performance of the model solving processes. The results for the SWPSP is effective in solving the proposed problem.
1295
Authors: Yu Lin Yang, Zheng Hao Ma
Abstract: As a result of the urgency of runway reconstruction and the inevitability of taking non-suspending reconstruction, time, cost and quality are taken as three basic objectives of the optimization with the complex environment of the runway, and the special related constraints are taken into consideration as well. Combining the other two objectives with the time objective and quantifying three objectives in the same way help to present the multi-objective model that is based on the multi-attribute utility function theory. Establishing the project network of asphalt repaving project and using the critical path method contribute to dealing with the uncertainty and randomness based on the distribution of process time by the three-point estimation method. Particle swarm optimization (PSO) algorithm helps solve the model and offers a scheduling plan of the critical path. In the end, one non-suspending the construction project of the runway is taken as an example and it proves the validity of the model compared with the related researches and the actual applied schedule.
1884
Authors: Yan Li, Zhi Run Xiao, Wen Qing Dou, Ying Yang
Abstract: The Skilled Workforce Project Scheduling Problem (SWPSP) is a complex problem of task scheduling and resource assignment that comes up in the daily management of many company Service Centers. In this paper we present a constraint programming (CP) approach for the SWPSP. We extend the project scheduling literature by developing a project scheduling model that accounts for differing skills among workers. The computational results for the SWPSP show that the constraint programming approach increases the performance of the model solving processes. The results for the SWPSP is effective in solving the proposed problem.
1669
Authors: Chang Sheng Yi, Jian Bing Gao, Xue Bin Guan
Abstract: The efficient management of energy research and development (R&D) projects is important to reduce the required the development time and cost. However, each development project is unique and innovational in nature and the duration of activities involved in an energy R&D project often cannot be predicted accurately. The uncertainty of activity duration may lead to incorrect scheduling decisions. The objective of this paper is to develop a fuzzy scheduling methodology to deal with these problems. Fuzzy variables theory is used to model the uncertain and flexible temporal information. A fuzzy scheduling algorithm with depth-first search is developed to find the possible critical paths based on fuzzy expected value simulation. A numerical example with solar photovoltaics development project is used to illustrate the effectiveness of the methodology.
806
Abstract: Time interval and distance interval are the two main constraints restricting the relationship among activities in the linear scheduling method. However, in previous researches, these two constraints are always considered separately, hence resulting in different linear scheduling models. In this paper, a linear scheduling model with two-dimensional constraints, considering both the time interval and the distance interval, was proposed. Meanwhile, a new algorithm was applied to this model. An example from literatures was calculated using the new method, the correctness of which was then confirmed by the results.
1077
Authors: Yan Li, Lloyd Gibson
Abstract: In this paper we present a genetic algorithm for the multi-mode resource-constrained project scheduling problem (MRCPSP), in which multiple execution modes are available for each of the activities of the project. To solve the problem, we apply a hybrid genetic algorithm, which makes use of nonrenewable resource feasibility checking procedure, local search based mutation and topological sort procedure. We present detailed computational results for the MRCPSP, which reveal that our procedure is effective in solving the problem.
2369
Authors: Ying Xin Zhang, Chao Chen, Jian Mai Shi
Abstract: The objective of this paper is to develop procedures for allocating resources to the activities of a given baseline schedule in order to minimize the number of extra precedence relations imposed by resource flows. Based on a proposed parallel resource flow generation scheme, two priority rule-based heuristics and a genetic algorithm are proposed. Finally, a set of computational experiments on standard benchmark datasets are presented to validate the heuristics.
1539