(软件工程课后习题答案第八版.doc

软件工程课后习题: ???????? What are the differences between generic software product development and custom software development? ???????? Solution: 重要区别为：在通用软件的开发过程中，详细说明（规格说明书）由产品开发者来制定，在定制软件产品开发过程中，详细说明（规格说明书）由客户来制定。 ???????? What are the four important attributes which all software products should have? Suggest four other attributes that may sometimes be significant. ???????? Solution: For important attributes are maintainability可维护性, dependability 可靠性, performance(efficiency)有效性 and usability可用性. Other attributes that may be significant could be reusability可复用性 (can it be reused in other applications), distributability 可分发性(can it be distributed over a network of processors), portability可移植性 (can it operate on multiple platforms) and inter-operability互用性 (can it work with a wide range of other software systems). ???????? What is the difference between a software process model and a software process? Suggest two ways in which a software process model might be helpful in identifying possible process improvements. ???????? Solution: A software process is what actually goes on when software is developed. A software process model is an abstraction and simplification of a process. Process models can be used to help understand real processes and to identify which aspects of these processes could be supported by CASE tools. 软件过程就是指在软件开发过程中所做的一些事情。软件过程模型是过程的抽象和简化。过程模型可用于帮助理解真正的过程，并可用于识别过程中的哪些方面可用CASE工具支持。 ???????? Giving reasons for your answer based on the type of system being developed, suggest the most appropriate generic software process model that might be used as a basis for managing the development of the follow systems: 1) Anti-lock braking system 2) Virtual reality system 3) University accounting system 4) Interactive timetable Solution: (a) Anti-lock braking system: Safety-critical 安全鉴定system so method based on formal transformations with proofs of equivalence等价 between each stage. (b) Virtual reality system: System whose requirements cannot be predicted预知 in