Requirements engineering: a review and research agenda

This paper reviews the area of requirements engineering. It outlines the key concerns to which attention should be devoted by both practitioners, who wish to "reengineer" their development processes, and academics, seeking intellectual challenges. It presents an assessment of the state-of-the-art and draws conclusions in the form of a research agenda

An editor and transformation system for a Z animation case tool.

In order to remain competitive, modem systems developers are increasingly under pressure to produce software solutions to complex problems faster and cheaper, whilst at the same time maintaining a high level of quality in the delivered product. One of the key quality measures is the delivery of a system that meets the customer's requirements. Failure to meet the customer's requirements may engender significant re-design, which in turn will cost money, delay product introduction and may seriously damage the developer's credibility. For these reasons, the problem of developing a precise and unambiguous statement of requirements for a proposed system is perhaps one of the most challenging problems within software engineering today. Formal, model-based specification languages such as the Z notation have been widely adopted within the context of requirements engineering, to provide a vehicle for the development of precise and unambiguous specifications. However, the mathematical foundation upon which these notations are based often makes them unapproachable and difficult to assimilate by a non-specialist reader. The problem then faced is that if the customer cannot understand the semantics of the specification, how can the customer agree that the specification is indeed a true reflection of the requirements for the desired system? Several researchers have proposed that rapid prototyping and animation of specifications can be used to increase the customer's understanding of the formal specification. This is achieved by executing specification components on candidate data and observing that the behaviour is as expected. However this requires that the original formal specification be reliably transformed into a representation capable of being executed within a computer system. To achieve this aim requires the support of computer-based tools able to assist the requirements engineer in capturing, manipulating and transforming the formal specification in an efficient and consistent manner. This thesis describes the research and development of the TranZit tool, which is a Z notation editor, checker and transformation system. TranZit supports the efficient capture and maintenance of Z notation specifications using the Windows Graphical User Interface, supported by a suite of powerful language-driven features. In addition TranZit contains a highly integrated and optimised syntax and type checker, combining traditional compiler design techniques with innovative use of object-oriented data structures and methods, to assist the requirements engineer in ensuring the internal consistency of the captured specification. Most importantly, TranZit contains a novel transformation engine, which is capable of transforming a captured Z specification into an executable representation based on extensions to LISP, suitable for direct execution in an animation environment. This process is supported by an eclectic strategy combining automated transformation with user assistance, to overcome many of the well-documented problems associated with transforming non-executable clauses in formal specifications

An object-oriented modelling method for evolving the hybrid vehicle design space in a systems engineering environment

A combination of environmental awareness, consumer demands and pressure from legislators has led automotive manufacturers to seek for more environmentally friendly alternatives while still meeting the quality, performance and price demands of their customers. This has led to many complex powertrain designs being developed in order to produce vehicles with reduced carbon emissions. In particular, within the last decade most of the major automotive manufactures have either developed or announced plans to develop one or more hybrid vehicle models. This means that to be competitive and o er the best HEV solutions to customers, manufacturers have to assess a multitude of complex design choices in the most e cient way possible. Even though the automotive industry is adept at dealing with the many complexities of modern vehicle development; the magnitude of design choices, the cross coupling of multiple domains, the evolving technologies and the relative lack of experience with respect to conventional vehicle development compounds the complexities within the HEV design space. In order to meet the needs of e cient and exible HEV powertrain modelling within this design space, a parallel is drawn with the development of complex software systems. This parallel is both from a programmatic viewpoint where object-oriented techniques can be used for physical model development with new equation oriented modelling environments, and from a systems methodology perspective where the development approach encourages incremental development in order to minimize risk. This Thesis proposes a modelling method that makes use of these new tools to apply OOM principles to the design and development of HEV powertrain models. Furthermore, it is argued that together with an appropriate systems engineering approach within which the model development activities will occur, the proposed method can provide a more exible and manageable manner of exploring the HEV design space.The exibility of the modelling method is shown by means of two separate case studies, where a hierarchical library of extendable and replaceable models is developed in order to model the di erent powertrains. Ultimately the proposed method leads to an intuitive manner of developing a complex system model through abstraction and incremental development of the abstracted subsystems. Having said this, the correct management of such an e ort within the automotive industry is key for ensuring the reusability of models through enforced procedures for structuring, maintaining, controlling, documenting and protecting the model development. Further, in order to integrate the new methodology into the existing systems and practices it is imperative to develop an e cient means of sharing information between all stakeholders involved. In this respect it is proposed that together with an overall systems modelling activity for tracking stakeholder involvement and providing a central point for sharing data, CAE methods can be employed in order to automate the integration of data.EThOS - Electronic Theses Online ServiceGBUnited Kingdo