在进行系统设计和编码之前，项目组在详细需求调研的基础上，将客户需求（包括功能需求和非功能需求）进行系统性的需求分析形成本文档。该文档作为项目组进行项目实施的指导性文件，同时作为项目验收的标准文件。-During the system design and coding before the project team needs in a detailed study based on customer demand (including the functional requirements and non-functional requirements) to carry out a systematic analysis of the demand for the formation of this document. The document as a project team to guide implementation of the project document, at the same time as the acceptance criteria for project documents.