选择（软件工程分析与设计）外文文献翻译.docVIP

Selection 1.1 PROBLEM-SOLVING AND DECISION-MAKEING It is helpful at this stage to introduce the ideas of problem solving, a structure for which was first described by Dewey (1910). The stages identified by John Dewey were: What is the problem? What are the alternatives? Which alternative is best? You should now be in a position to identify a resemblance between Dewey’s three stages and the software life cycle. Enough has been said about the life cycle earlier for us to spot a distinct resemblance between the first stage of problem definition and our requirements analysis phase. In fact many organizations use the term ‘problem’ or ‘project definition’ rather than ‘requirements analysis’. The final two stages may similarly be identified as being equivalent to the phase that we refer to as ‘design’. A more recent, but very relevant structure has been supplied in the context of decision-making (Simon, 1960). Professor Simon labels the stages of decision-making as follows: Intelligence activity, Design activity and Choice activity. The term ‘Intelligence’ is used here in the military sense, i.e., searching the environment for conditions requiring a decision to be made. ‘Design’ is concerned with inventing and developing possible courses of action. The activity of selecting a particular course of action from those available is known as ‘chose’. In this case our requirements analysis corresponds to the intelligence activity. Although the software designer does not need to search too hard for circumstances requiring a decision to be made, they will normally be found lying on his or her desk labeled ‘Specification of requirement’. However Simon’s use of the term ‘Design’ differs from ours. Whereas Simon uses the word to describe the generation of possible solution, we use it in the sense that selection is included also. There seems to be some justification for believing that problem-solving, decision-making and software analysis and design share a common framewo