考虑风险因素的工程项目动态模糊多目标优化研究

发布时间：2019-02-15 20:48

【摘要】：在工程项目中,多个目标间的协调与管理是项目管理的一项重要内容,对项目工期、成本与质量等方面的目标实现有着直接的影响。当前工程项目投资呈现出规模大、周期长、面临风险众多等特点,这对项目的多目标协调管理提出了更高的要求。因此,对工程项目的各目标进行分析与优化研究,是实现多目标均衡协调的基础;而综合考虑工程项目所面临的风险性及其所处环境的动态性,则可使目标优化更加符合实际情况,且为实际管理提供理论依据。本文以工程项目的多目标优化为研究对象,基于传统的多目标优化理论,引入模糊集理论、效用理论、动态优化理论,通过参数模糊化、选取置信水平、多属性效用函数评价及加入时间参数体现风险因素和动态环境因素的影响,构建了考虑风险因素与动态环境因素的多目标优化一般模型;分析工程项目多目标特点与相互关系,提出工期-成本均衡优化函数与工期-质量均衡优化函数,结合改进的一般优化模型构建了考虑风险因素的工程项目动态模糊多目标优化模型,并选取适用于求解动态优化问题的微粒群算法;在此基础上,进行了算例分析,在给定的项目工序关系与其他参数的条件下,分别以静态和动态视角进行建模与求解,静态模型求解对比分析不同置信水平所代表的决策风险大小对帕累托解的影响;动态模型求解对比分析不同阶段由于决策者偏好的不同对帕累托解产生的影响。算例结果表明,随着置信水平的提高,帕累托解分布区域无明显变化,但其分散程度与模糊程度降低,说明项目决策风险的减小使得最优方案集变得更加清晰,有利于决策者对最优方案的选择;随着项目阶段的推进,帕累托解的分布有明显变化,说明由于决策者目标偏好由重视质量逐渐变为重视工期,最优解在工期目标上有更好的表现;验证了本文所建立的考虑风险因素的工程项目多目标动态优化模型的可行性与合理性。
[Abstract]:In engineering projects, the coordination and management of multiple objectives is an important part of project management, which has a direct impact on project duration, cost and quality. At present, the project investment has the characteristics of large scale, long period and numerous risks, which puts forward higher requirements for the multi-objective coordinated management of the project. Therefore, the analysis and optimization of the objectives of engineering projects is the basis of achieving multi-objective equilibrium and coordination. Considering the risks faced by the project and the dynamic nature of the environment, the optimization of objectives can be more in line with the actual situation, and provide a theoretical basis for the actual management. Based on the traditional multi-objective optimization theory, fuzzy set theory, utility theory and dynamic optimization theory are introduced in this paper. The multi-attribute utility function evaluation and adding time parameters reflect the influence of risk factors and dynamic environmental factors, and a general multi-objective optimization model considering risk factors and dynamic environmental factors is constructed. Based on the analysis of the multi-objective characteristics and the relationship of engineering projects, the optimization function of time-cost equilibrium and the optimization function of time-quality equilibrium are proposed. Combined with the improved general optimization model, the dynamic fuzzy multi-objective optimization model of engineering project considering risk factors is constructed, and the particle swarm optimization algorithm suitable for solving dynamic optimization problem is selected. On the basis of this, an example analysis is carried out. Under the condition of given project working procedure relationship and other parameters, the model and solution are built and solved in the static and dynamic visual angle, respectively. The influence of the decision risk represented by different confidence levels on the Pareto solution is analyzed comparatively by solving the static model. The effects of different decision makers' preferences on the Pareto solution in different stages are analyzed. The numerical results show that with the increase of confidence level, the distribution region of Pareto solution does not change obviously, but the degree of dispersion and ambiguity decreases, which indicates that the reduction of project decision risk makes the optimal scheme set more clear. It is advantageous for the decision maker to choose the optimal scheme; With the development of the project stage, the distribution of Pareto solution changes obviously, which indicates that the optimal solution has a better performance on the target of the time limit because the preference of goal of decision maker gradually changes from emphasizing quality to attaching importance to time limit. The feasibility and rationality of the multi-objective dynamic optimization model with risk factors are verified.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU71

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