The Research On The Technology Of Requirement Analysis Modeling And Model Verification

As computer technology is being used more and more widely, now the sizes of the software used in domestic or abroad aerocrafts are larger and larger. They are realizing more and more functions. After making adequate analysis upon the errors ever occurred in areospace computer system, together with a lot of case data, we can see it distinctly that the software specifications are often the important sources of the errors. Software specification is the product of the requirement analysis phase. We often write it using natural language which is non-formalized and without any constraints. Although the software specification described using natural language is easy to write and understand, its validity, integrality, non-ambiguity, consistency are hard to guarantee. The process of verification can only be done by manpower which is not normative and not rigorous. And the complexity of a lot of software has made it impossible to check the specifications artificially.As an important branch of Software Engineering, Requirement Engineering is a subject which is around the technologies, methods to help making the requirement analysis and definition of the external characterisctics of the object system. Requirement acquirement, description, verification is the main contents of the Requirement Engineering research.The main idea of this paper is about the research of the technology of the requirement analysis modelling and model verification. The word "analysis model" refers to the semi-formaliztion of the requirement specification. In this paper, the technologies of requirement analysis modelling based on two main analysis methods : structured analysis (SA) and Object Oriented Analysis (OOA) are introduced in detail, including the history and the main idea of the analysis methods, the components of the analysis models. Then the model verification is discussed, including the concrete jobs of verification, the implementation principle of the two ways: static verification and dynamic verification. According to the current software development level of the domestic aerospace industry and the characteristics of the aviation software, this paper selects a set of structured modelling technology supporting control and state transition, which is expected to be a requirement analysis criterion in domestic aerospace industry. At the same time, to accelerate the spread of the criterion, a CASE tool: TSA which supports the modeling technology metioned above is developed. Combined with the role CASETools play in requirement analysis phase and the actual needs of the requirement analyzer, the paper shows the design process of TSA. On the basis of the design frame, the main implementation approaches are narrated.TSA was tested during the requirement analysis phase of the software "Aerospace Distributed Unit (HDU)" , which verified its usefulness during assisting in analysis modeling and model verification.