说明：  This book was written to help provide an understanding of th hallenges in requirements engineering (RE) that are facing industria actitioners and to present some best practices for coping with thos hallenges. Many texts on RE generally do a good job covering th asics of RE, but they may not adequately discuss the real-world oblems that can make requirements elicitation, analysis, and anagement difficult. For example, Siemens products are typically efined with at least several thousand recorded requirements omplex Department of Defense projects are sometimes reported a