【作者】 郭姝媛；

【导师】 张述伟； 王克峰；

【作者基本信息】 大连理工大学 ， 化学工艺， 2005， 硕士

【摘要】 化工过程模拟是一个复杂的过程,需要具备足够的专业知识和经验才能够对工艺流程进行较好的模拟和优化。因此,开发一个化工过程模拟辅助设计专家系统来指导正确有效地进行模拟优化是十分必要的。本文将人工智能及数据库技术各自的优点有机地结合起来,根据专家系统基本原理,充分发挥关系数据库的强大数据处理能力,采用基于案例的推理方法,使用Visual Basic 6.0和Microsoft Access 2003开发了一个用于化工过程模拟的专家数据库系统。 (1)本系统将知识以一定的组织形式存贮在关系数据库的表中,利用数据库管理模块对其进行管理,可以方便地对知识库进行修改、增加和删除。对于模拟中比较复杂的物性方法选择,系统可以根据流程的工艺特点及物系性质帮助用户选择适合的物性方法。 (2)系统采用基于案例的推理(CBR)方式,将以往案例储存在案例库中,用户可以通过参考以往相似的成功案例来进行新工艺过程的模拟,参考在数据库中储存的专家知识作为指导,而不必从头开始模拟,从而使全流程模拟得到了简化,并提高了准确性。应用标准数据库查询语言(SQL)及VB语言对知识及案例进行推理,继承了专家系统中知识库与推理机相互独立的优点,知识库的任何修改、增加、删除都不用改动处理知识库的程序,程序和数据彻底分离,提高了各功能模块的逻辑独立性,增加了专家系统的通用性。 (3)系统实现了与化工模拟软件ASPEN PLUS之间的接口,使二者可以进行数据传输,用户可以直接利用已有的相似案例在ASPEN PLUS中的输入/输出文件,在系统界面下进行修改,实现新流程的模拟,使用户不必在模拟软件中从头开始模拟,很大程度上扩展了模拟软件的实际工程应用,极大地方便了各类用户的使用,为化工过程模拟提供了强有力的支持。更多还原

【Abstract】 Chemical Process Simulations are a complex one, when sufficient special knowledge and hands-on experiences are essential to get a better understanding and subsequently better simulations and optimizations of process flowsheet. So it highlights the necessary of development on Aided Design Expert Database System (ADEDS) for chemical process simulations. Both Artificial Intelligence (AI) and Database (DB) technology have the advantages and limits respectively, fortunately, the ADEDS can band the two together flexibly. Based on the principles of Expert System (ES) and powerful data processing ability of RDBMS (Related Database Management Systems), ADEDS for simulation design of chemical engineering process is developed by using Visual Basic 6.0 and Microsoft Office Access 2003. Knowledge and case are represented in the table of database and reasoned by database language.(1) Storing all the relevant knowledge in a specific way of organization in the tables of RDBMS, by using managing modules, ADEDS offers an easy way to edit, add and delete the knowledge in Knowledge Base (KB). For complex property methods selection during the simulation process, ADEDS can help users pick out appropriate property methods according to the characteristics of technology and material categories.(2) Using Case Based Reasoning (CBR) as the way of reasoning, storing all the old cases in Case Base, ADEDS can direct user to simulate new process by referring to previous similar cases and don’t have to start from the beginning, making the simulation much simpler. Reasoning by SQL and VB, KB and reasoning separate from one another, any editing, adding and deleting the data of KB can be done without modifying program, which make ADEDS more universal.(3) ADEDS realized the interface with chemical engineering simulation software-Aspen Plus, users can apply the import or export files embedded in Aspen Plus as the exiting similar cases of ADEDS directly, and by revising, a new process simulation can be easily accomplished; Users don’t have to start the simulation work all at the first beginning, thus applications of simulation software on practical engineering have been widened extensively through this System, which is also a powerful backbone for chemical engineering simulations.更多还原