Page - 19 - in Intelligent Environments 2019 - Workshop Proceedings of the 15th International Conference on Intelligent Environments

particularly concerned with guiding the systems engineering part in a stepwise way with the goal of delivering a quality system that meets user needs. Traditionally, SE has been extensively used to manage the engineering of highly complex systems such as those used in aerospace, defense and security over the last decades [9, 10, 19, 28]. Often, these projects were carried out by government agencies or large organisations and had strict targets for time, cost and quality [5, 11]. There is also plenty of evidence in the literature regarding the suitability of SE for effectively managing the engineering of complex projects, reducing risks and creating successful systems [5, 7, 16, 18]. In a comprehensive study by [17], it was established that common systems engineering activities contribute towards overall success and technical quality. However, SE has evolved considerably over the past two decades [27]. This has spawned a number of standards and system life cycle process models such as linear, vee, spiral, waterfall, agile and model based systems engineering. As a result, there is no single model that is accepted worldwide that fits every possible situation [7, 27]. Fortunately, all life cycle models subdivide the system life into a set of basic steps that separate major decision milestones. One such model is the generic life cycle model proposed by [17]. It is representative of the majority of systems that are developed including those containing significant software functionality at component level and is based on the convergence on three major sources: the Department of Defence Acquisition Model (DoD 5000.2), the International model ISO/IEC 15288 and the National Society of Professional Engineers (NSPE) model. Hence, in this study we adopted this generic lifecycle model as basis for our evaluation framework. 4. The proposed evaluation framework The evaluation framework consists of three main stages as shown on Figure 1. The first two stages cover the developmental part of the life cycle while the third the post development period. The figure also shows the main inputs and outputs of each of the stages: those above the blocks refer to specifications and documentation whereas those below represent the evolution from concept to operational system. Figure 1: Principle stages in the lifecycle [13] Concept development stage is the initial stage in the lifecycle. In [17], the authors attest that the decisions made during this stage determine the outcome of the project. The Concept Development Engineering Development Postdevelopment Technological Opportunities Defined System Concept(s) Production System Installed Operational System Operational Deficiencies System Functional Specifications System Production specifications Operations and Maintenance Documentation A.Santokheeetal. /TowardsaGeneralFramework forEvaluating IEs’Methodologies 19