Based on the different roles played by base flow and alternative flow in the process to achieve user＇s goals, we have found that loop structure is frequently used to implement alternative flow and/or to connect different use cases. This paper presents an approach to identify base flows and alternative flows of different use cases by traversing control flow graph in which back edges are eliminated. The effectiveness of the approach is verified by identification of the use case structure of an ATM system. The workload of human intervention of the approach is relatively slight, and the manner of human intervention closely follows the usual process of software comprehension.
Website navigability is acquiring a growing importance in website design and redesign,quality evaluation,and improvement.Existing navigability measures mainly depend on site link structure,so that they only consider the impact of site link structure for navigability and ignore the impact of Web page content.A continuous Markov chain model which depicts the user＇s surfing behavior can balance these two factors in the evaluation of website navigability,and it needs to estimate the page transition probabilities and user stay time according to user access log.In this way,we can obtain more reliable results for website navigability measure than the existed methods.Experiments show that our method is effective.
