1、 西安邮电 大学 毕 业 设 计（论 文） 外文文献翻译 院（系） ： 自动化学院 专 业： 智能 科学与技术 班 级： 智能 0801 班 学生姓名： 万云艳 导师姓名： 韩中 职称： 讲师 起止时间： 2012 年 3 月 8 日 至 2012 年 6 月 20 日 英文原文 298 SHEARD AND MOSTASHARI Table I. Complex System Examples Systems Engineering DOI 10.1002/sys PRINCIPLES OF COMPLEX SYSTEMS FOR SYSTEMS ENGINEERING 299 reason
2、 all should be amenable to improvement based on the principles for engineering complex systems addressed in later sections. Systems engineers should be familiar with the three examples: INCOSE The systems engineering (SE) process within a company The National Airspace System (air traffic control sys
3、tem). Table I shows that all three examples have all complex systems attributes listed above and therefore that these are complex systems. 3.2. Systems-of-Systems It should be noted that Systems-of-Systems (SoSs) is currently of great interest to systems engineers. The topic was originally defined b
4、y Maier, 1998； confer-ences and papers addressing systems-of-systems have increased greatly in the last few years. Systems-of-sys-tems issues that differ from systems issues include: Integration of independently-operational compo-nent systems that were built for other purposes Rapid evolution of bot
5、h user needs and system technologies, which prevents stable requirements Multiple disparate stakeholders with conflicting needs and a lack of incentives to participate in the system-of-systems Distributed development and its consequent com-munication problems Dependence on an integrated computing in
6、fra-structure that has extremely high and increasing complexity, thus threatening unintended conse-quences. In an engineering context, systems-of-systems are often, but not always, complex systems. Figure 2 shows this comparison. Systems-of-systems usually come up in a program acquisition context, a
7、nd are distinguished as being unmanageable using standard top-town sys-tems engineering, whereas complex systems usually come up in an analytical or scientific context, and are described as being not decomposable. Most systems-of-systems are also complex systems (CxSs) and vice versa； hence the two
8、top circles overlap greatly. A system such as Joint Strike Fighter that is developed via a program manager and a chief engineer is by definition not a complex system (there are not independent agents). However, it specifically is consid-ered a system-of-systems in some Defense Department work Chairm
9、an, Joint Chiefs of Staff, 2007, although not according to the more generally accepted definition DOD AT&L, 2006, which is much more like the Maier definition. In contrast to long-lead top-down-developed systems, ad hoc systems-of-systems are pulled together at the last minute by operational person-nel and do not have chief system integrators nor a
