An eighth-order exponentially fitted two-step hybrid method of explicit type for solving orbital and oscillatory problems

The construction of an eighth-order exponentially fitted (EF) two-step hybrid method for the numerical integration of oscillatory second-order initial value problems (IVPs) is considered. The EF two-step hybrid methods integrate exactly differential systems whose solutions can be expressed as linear combinations of exponential or trigonometric functions and have variable coefficients depending on the frequency of each problem. Based on the order conditions and the EF conditions for this class of methods, we construct an explicit EF two-step hybrid method with symmetric nodes and algebraic order eight which only uses seven function evaluations per step. This new method has the highest algebraic order we know for the case of explicit EF two-step hybrid methods. The numerical experiments carried out with several orbital and oscillatory problems show that the new eighth-order EF scheme is more efficient than other standard and EF two-step hybrid codes recently proposed in the scientific literature

Modelling the critical success factors of agile software development projects in South Africa

There are several critical success factors suggested for why agile software development projects succeed, including organisational and process factors. Although there are an increasing number of identified critical success factors, IT professionals lack the modelling techniques and the theoretical framework to help them meaningfully understand their influences. To solve this problem, this study developed a model by employing the following theories: Theory of Reasoned Action (TRA), Theory of Planned Behaviour (TPB), and Unified Theory of Acceptance and Use of Technology (UTAUT) to create a fit model for agile software development projects. The research sought to answer the question: What are the critical success factors that influence the success of agile software development projects? The literature review considers the continued failure of agile and traditional software development projects which have led to the consideration of, and dispute over, critical success factors — the aspects most vital to a methodology’s success. Though TRA, TPB and UTAUT have previously been applied to agile methodologies, empirical models have not been completely integrated to develop a fit model. This research sought to fill this gap. Data was collected in South Africa through a web-based survey using structured questionnaires and an interview guide. Face-to-face interviews were done to identify the critical success factors in agile projects. The data was captured and analysed for descriptive statistics, convergent and discriminant validity, composite and internal reliability, and correlation in order to inform the structural equation modelling (SEM). SEM was used to test the research model and hypotheses to answer the research questions. The results informed development of a comprehensive model that could provide guidelines to the agile community. The study contributes towards understanding the critical success factors for agile projects. It examined direct, indirect and moderating effects, and the findings contribute towards developing a framework to be used by agile professionals. These key result shows that organisational factors have a great influence on performance expectancy characteristics. To ensure success of agile projects, managers are advised to focus on the effect of the organisation’s environment, culture and policies on performance and effort expectancy.School of ComputingPh. D. (Computer Science