Demand Project Overview
Zhang Yousheng
(This article is reproduced from Software Engineering Expert Network
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Software demand refers to the user's expectations for the target software system in terms of function, behavior, performance, design constraints. Through the understanding and analysis of corresponding problems and its environment, the information, functions and system behavior of the problem are established, and the user needs precise, completely, and finally forms a demand specifications. This series of activities constitutes software development life cycle. Demand analysis phase. Demand analysis is a bridge between systematic analysis and software design stages. On the one hand, demand analysis is based on system specifications and project planning as the basic starting point of analysis activities, and inspects them from software perspectives; on the other hand, demand specifications are software design, implementation, test until main basis for maintenance. . Good analytical activities help to avoid or eliminate early errors as soon as possible, increasing software productivity, reducing development costs, and improving software quality. With the development of the computer, the demand project has developed in the initial stage of computer development, software development is not very concerned about the code writing, and the demand analysis is rarely valued. Later, software development introduced the concept of life cycle, and demand analysis became its first stage. With the expansion of the size of the software system, demand analysis and definition is increasingly important in the entire software development and maintenance process, directly related to the success of the software. People gradually realize that demand analysis activities are no longer limited to the initial stage of software development, which runs through the entire life cycle of system development. In the mid-1980s, the subsequent domain - Requirementengineering, RE is formed. Since the 1990s, demand projects have become one of the hotspots of research. Since 1993, an international seminar (ISRE), a demand engineering (ICRE) was held every two years since 1994, which released a new publication in 1996 Springer-Verlag-" RequirementSengineering ". Some working groups on demand projects have also been established, such as Renoir (RequirementSengineeringNetworkOfinternationalCooperatingResearchGinternationalCooperatingResearchGroups), and start working. The basic content demand project of demand project refers to the application has proven effective technologies and methods to analyze, determine customer needs, and help analyst understanding questions and defines all external features of the target system. It describes the system and its behavioral characteristics and related constraints by appropriate tools and marks, forming a demand document, and supports the demand evolution of users with continuous changes. RE can be divided into system requirements project (if it is a whole system consisting of hardware and software) and software requirements project (if only specifically for pure software part). Software demand project is a discipline that analyzes and records software requirements. It breaks down system requirements into some major subsystems and tasks, assigns these subsystems or tasks to software, and through a series of repetitive analysis, design, comparative research. The prototype development process converts these system requirements into software demand descriptions and some performance parameters. The demand project is a process of repeated demand definition, document record, demand evolution, and finally freeze demand on the basis of verification. In the 1980s, Herbkrasner defined five-stage lifecycle of demand projects: demand definition and analysis, demand decisions, forming demand specifications, demand implementation and verification, demand evolution management. Recently, Matthiasjarke and KlauspoHL have proposed three-stage cycle: gain, representation, and verification.
