Quantitaive Study On Time-cost-quality Optimization Of Engineering Project Based On Immune Genetic Algorithm

Following the pace of reform and opening up, the construction industry has achieved amajor breakthrough in our country, which from the design idea to the level of technology.Especially in recent years, in the support of national policy orientation and economic,commodity house, commercial building, large public construction projects have been therapid development.The Shanghai world financial center, the National Stadium, Hangzhou BayCross Sea Bridge created over one and one milestone events in Chinese construction industryhistory. However, with the increasing in size and number, management becomes morecomplex and difficult. Especially, managers how to grasp and control the project objective isparticularly important. Time,cost,quality are the basic goals of project objective systems.Theywill have a direct impact on the entire project.Therefore, managers primary task is how tocoordinate the relationship between the three objectives.In practice, the three goal has a unityof opposites relationship,which want to reach the best state of them is very difficult. We justcan constantly balancing and coordination the relationship of them to achieve the overall goalof the project. Therefore, we need to analysis the relationship between the three goals andestablish an effective model to optimization.At first this paper introduces the theory and method of the multi-objective optimizationand analyzes the problem of multi-objective optimization of project. Then, in terms of thetime, cost and quality of the project, this paper scientifically conducts a detailed study. First,the project is divided into many activities with several processes, in which the multi-objectiveproblems study. Second, it systematically analyzes the research results of the domestic andforeign scholars about time, cost and quality. Such as the relationship between the threegoals、the model establishment of the three goals、the solving of the model. Based on which,the research ideas of this paper in time, cost and quality are put forward.Traditional multi-objective optimization methods of time-cost-quality of project establishmodel generally based on the hypothesis of the linear relationship between time-cost,time-quality. However, the relevant data and information indicate that it is not a linearrelationship between them in the actual projects. This paper assumes that the relationshipbetween time-cost and time-quality is the quadratic function and builds model according tothe fitting of relevant data by experts. After the establishment of three goals model, analysisof the characteristics and defects of genetic algorithms, apply an immune genetic algorithm tosolve the model. In the algorithm, for the sake of reducing the computation complexity, theEuclidean distance, instead of the information entropy, is used to calculate the similar antibodies. Besides, in this paper the similarity vector distance determines the choice ofprobability in the selection of the genetic. Finally, a numerical case is used to verify thefeasibility of the models and the rationality of the algorithm, and the results indicates that themodel can maximize profits for contractors as well as meeting the requirements of theowners.