A Requirement Analysis Technique Based On The Integration Of Problem Frames And Goals

With the rapid development of computer science and information technology, and the popularization of the Internet of Things, cloud computing and big data etc, some new types of applications and systems have emerged in recent years. The scale and complexity of software systems have expanded tremendously, which results in increased the failure rates and delays in many software development projects involving medical devices, aerospace industries, traffic systems, information security systems of governments. According to their long-term observations and investigations, the Standish Group have conducted a large number of surveys and empirical studies, and found that the most significant contributing factor to IT project failures is mistakes made at the requirements stage. Therefore, modeling and analysis techniques, particularly integrating existing requirements modeling techniques is of great importance in both theoretical research and practical applications.As we all know, now people still maintain enthusiasm and interest for the requirements engineering,and they put forward some methods for requirements modeling and requirements analysis, these methos are mainly including the case method、scenario method、goals method、 multiple viewpoints、ontology method and problem frame.The work of this paper is mainly to combine problem frame and goals, which aims to take advantage of the two methods in requirements modeling, also to complement limitations of them in the process of capturing requirements. Problem frame pays attention to considerating the reality and related environment of the software system, it considerates system context fully in the process of requirements modeling and it provides a structured requirement model with problem figure, so that, the process for requirement obtaining will be more objectively and accurately. However the method of problem frame has limitations. First,it is abstract so that it is hard for people to understand. Second, it can not afford the fomal expression for requirement.The method of goals is mainly to collecte goals and then makes the goals as the source of capturing requirements. The goals methtod has some advantages.For example, at first, it is conforming to the ways of thinking for people. Second, it is helpful to understand the requirements document. What is more,it can be used in a formalized way to express requirements, in this way, it is easy to valify the requirements. However, goals method has disadvantages. Because, the way to obtain the goals is loose and open, in this way, there may be subjective factors in goal source. In the light of the above analysis, the two methods both have own unique advatages on the requirments modeling, also they have complementarity, so in this paper, the way by combining the problem frame and goals has certain research value.In this paper, it introduces the research background、significance and research status at home and abroad in the first chapter, and introducing the requirements engineering in the second chapter. Next,it introduces the basic knowledge and definition related to problem frame and goals in the third chapter, which gives the following research theory foreshadowing. Then it in the fourth chapter of this article, it is mainly to introduce the researching process, namely the thinking of combining the two methods, and using an example to demonstrate the process and the feasibility of this idea in the fifth chapter. Finally it discusses and looking to the future work in the sixth chapterThe main contribution of this paper can be summarized from three aspects as follows:(1) The KAOS method of goal-based has the limitation which is inadequate to analyze the context and description, so this paper puts forward a method that combines problem frame to overcome the limitations of KAOS method. Also it can be realized that the problem figure of problem frame matches the system goal, at the same time, it can help to improve the completeness and rigour for the process of analysising the requirement by providing the formal expression for the requirement itself and the mutual relationship.(2) In the process of requirements analysising for the methods of problem frame and goals, they usually demonstrate the static modeling process. So this article try to study from another perspective of dymamic analysis, namely introducing the message sequence chart (MSC) for dynamic modeling under the background of the two methods, also realizing the description and characterization for the requirement behavior and the process of interacting with the real world.So it make the the process of requirements modeling and analysis process more maneuverability, understandability and traceability.(3) This article uses the semi-automatic transformation method to make users’requirement model transform to software code design by basing on problem frame, also we call this method problem transformation[1].The result of the transformation is that requirement can be connected with machine domain directly. So that the requirement involves the machine domain only. At the same time, by linking the satisfied goal with requirement after transformation and through refining the goal, it eventually makes machine domain directly connected to the goal after refining, so that it can be more elaboration to the requirement of machine domain, In addition, This article uses the unique thought of problem frame with nonfunctional requirements modeling,which is considered as the quality requirements of the whole system, and also making the related application fields that involves them as subproblems, And then the reliability of the analysis and reasoning for the system is realized by using the technology of problem transformation. At last, this article demonstrates the specific researching process concretely by using a case study.