Multi-objective Optimization Research Of Linear Engineering Project Based On NSGA-?

In the field of project management projects,cost,duration and quality are the three major control objectives,and their research methods and research theories are maturing.Although many other goals have been derived from the field of engineering management research in recent years,these three goals are still the issues of concern in academia and engineering practice.The optimization research from single goal to multi-objective has never stopped,and will be deeper.The low cost,short construction period and high quality of the project are desirable for all decision makers,but the three are interrelated and mutually constrained,and more often,the goal of having one goal has to sacrifice other goals.Therefore,how to achieve the optimization and control of the three major objectives in the online engineering project has always been an important issue in academic circles and engineering practice.At present,the optimization of linear engineering projects at home and abroad mostly focuses on resource balance.There are few researches on the time-cost-quality multi-objective optimization of linear engineering projects with linear planning methods.This paper starts with the optimization of construction period-cost-quality multi-objectives.A multi-objective optimization mathematical model of duration-cost-quality was established.Due to the difference between the linear planning method and the network planning method,this paper discusses the linear activity,block activity and strip activity classification and establishes the mathematical model from the characteristics of the linear engineering project when the construction time target model is established.The constraints in the model are explained.In the cost target model,the direct cost,indirect cost and project delay cost of the linear engineering project are discussed,and the indirect cost expense rate is apportioned according to the activity time.At present,regarding the determination of quality problems,a large number of scholars have explored a variety of solutions from different perspectives,but this paper still adopts the expert scoring method to determine the quality.The experts who have practical experience in engineering still have high efficiency and high scores.reliability.The multi-objective problem optimization solution is non-unique,there is a set of Pareto solution sets,and the traditional mathematical programming method has limitations.The multi-objective genetic algorithm is an algorithm for solving and analyzing multi-objective optimization problems,compared with traditional mathematical programming.Algorithms,genetic algorithms are simple and efficient.The core of the genetic algorithm is to coordinate the relationship between the various objective functions,and find the optimal solution for each objective function to achieve a larger or smaller function value.Among many multi-objective optimization genetic algorithms,the nondominated sorting genetic algorithm(NSGA-II)with elite strategy is a multi-objective optimization genetic algorithm with large impact and wide application range.By combining the actual engineering cases,analyzing and calculating the construction period,cost and quality of each activity construction plan,the non-dominated sorting genetic algorithm with elite strategy is used to solve the multi-objective optimization problem of the linear engineering project,which is better than the actual project and meets the requirements of the project.Construction plan for engineering needs.