A Study on the Design Optimization System Using Knowledge Engineering Method

工程设计被认为是一个结构不良的问题；它不仅缺乏明确的求解算法，而且缺乏要达到的目标。在这一点上，知识工程有望将设计优化方法扩展到非结构化设计问题。对将知识工程引入工程设计进行了探讨。所得结果总结如下：1。首先从知识工程应用的角度对工程设计过程的特点进行了概述。研究发现，设计过程可分为几个步骤。即1)对设计需求的识别；2)寻找满足设计需求的候选设计方案；3)在候选设计方案中对可接受的设计方案进行评估；4)设计优化，确定最优设计方案。基于上述认识，采用知识工程技术与数值优化方法相结合的设计新方法，克服了上述的非结构化工程设计问题。这一概念是基于这样一种思想，即设计过程中不明确的领域，其解决方案依赖于设计师的经验，即设计知识，由知识工程技术支持，并通过数学优化方法解决其明确的领域。为了验证上述建议的正确性和有效性，开发了船舶动力装置设计的计算机系统。开发的系统不仅是设计的有效工具，而且是指导没有经验的设计师的有效工具。

Engineering design is considered to be an ill-structured problem; it lacks not only well-defined solving algolisums but also goals to be reached. In this point, the knowledge engineering is expected to expand the design optimization method to the ill-structured design problems. An investigation was done to introduce the knowledge engineering to engineering design. The results obtained are summeried as follows:1. Firstly the characteristic of engineering design process is discussed generally from the view point of the application of the knowledge engineering. It is found that the design process can be devided into several steps. Namely, 1) recognition of design needs; 2) search of the design candidates satisfying the design needs; 3) evaluation of the acceptable design solutions among the design candidates; 4) design optimization to determine the optimal design solution.2. Based on the above understanding, the new design method coupling the knowledge engineering technique and the numerical optimization method is adopted to overcome the ill-structured engineering design problem as mentioned above. This concept is based on the idea that the ill-defined domain of design process whose solutions depended on the designer's experiences, i.e., the design knowledge, is supported by the knowledge engineering technique, and the well-defined domain of them is solved by the mathematical optimization method.3. A computer system for the design of marine power plants was developed in order to ascertain validity and effectiveness of the above proposal.4. The developed system was found to be effective not only for the tool of the design but also as the tool of instructing inexperienced designers.