系统工程 系统与系统工程.ppt

第一章系统与系统工程 第一节 系统的基本概念 * * 第一节 系统的基本概念 第二节 系统工程的概念 第四节 应用举例 第三节 系统工程的方法论 1.1.1 系统的概念 (System Definition and Concepts) 《中国大百科全书》解释：系统是由相互制约、相互作用的一些部分组成的具有某种功能的有机整体 A system is a set of interrelated components working together toward some common objectives. A system is a combination of elements or parts forming a complex or unitary whole such as a river system or a transportation system. The elements of a system Systems are composed of components, attributes, and relationship. These are described as follows: 1.Components are the operating parts of a system consisting of input, process, and output. 2.Attributes are the properties of the components of a system. 3.Relationships are the links between components and attributes. 日本工业标准（JIS），系统含义是“许多构成要素保持有序化，向同一目的行动的集合体”。 系统的范围是相对的，它依所研究问题的需要而界定。一个系统的任何部分可以被看作一个子系统，而每一个系统又可成为一个更大系统中的一个部分。 （1） 目的性(Purposefulness ) 1.1.2系统的特性(Characters of System ) （2） 整体性(Entirety,Wholeness) （3） 集合性(Assembly,Aggregate) （4） 层次性(Hierarchy) （5） 相关性(Relativity,corelation) （6） 环境适应性(Circumstance adaptability) 1.1.3 系统的分类 Classification of System （1）自然系统与人造系统 Natural and man-made systems （2）实体系统与概念系统 Physical and Conceptual Systems （3）静态系统和动态系统 Static and Dynamic Systems （4） 封闭系统与开放系统 Closed and Open Systems 除此而外，还有其它一些分类的准则，如控制系统和行为系统，连续系统和离散系统，确定性系统和随机性系统，白色系统、灰色系统和黑色系统等。 A good example of the impact of man-made systems on natural systems is the set of problems that arose from building the Aswan Dam on the Nile River. Construction of this massive dam ensures that the Nile will never flood again, solving an age-old problem. However, several new problems arose. The food chain was broken in the eastern Mediterranean（地中海）, thereby reducing the fishing industry. Rapid erosion of the Nile Delta took place, introducing soil salinity (含盐量)into upper Egypt（埃及）. No longer limited by periodic dryness, the po