Problem statement: There seem to be perceptual incongruence between systems development managers and developers. Research shows that while managers are more positive towards systems development methodologies, developers on the other hand seem to resist and not to use systems development methodologies in their entirety but instead adapt, tailor, modify and change them depending on the project at hand (contingent use). Systems development managers can exert power through a variety of influence bases. However, these power influences may be perceived differently by developers. While some might feel constrained, others might actually feel liberated by the existence of the same influence base. Main findings: IS managers are using systems development methodologies to gain control over team members. However, there was no clear perception on whether systems development methodologies were enslaving systems developers. This was indicated by the majority of the respondents neither agreeing nor disagreeing to that effect. The research showed that most organisations are adapting the use of systems development methodologies on a project to project basis, which is referred to as the contingent use of systems development methodologies. Research method followed: The positivistic research paradigm was used as it allowed the researcher to find out patterns and regularities between power, systems development methodologies’ use and success. A survey was conducted and a questionnaire was used for data collection purposes. Questionnaire data was analysed using IBM SPSS Statistics Version 21, Release 20.0.0 software package tools. Principal conclusion: Power is interpreted in terms of the type of power that can be exercised by IT professionals specifically IS developers and their respective managers at the workplace. The roles assumed and the different power types that may be exercised in organisations provide a link as to who has the final say when it comes to the use and success rate of systems development methodologies. The contingent use of systems development methodologies provides a form of “freedom” to systems developers. Based on the research findings, the research proposes an answer to the question – are systems development methodologies enslaving systems developers and empowering IS managers? / MSc (Computer Science), North-West University, Potchefstroom Campus, 2014

A tecnologia Web foi criada como forma de divulgar o conhecimento científico, mas tem sido utilizada também como mecanismo de acesso a vários tipos de sistemas de informação empresariais assim como de comunicação entre eles, gerando diversas oportunidades de negócios para as organizações. Os sistemas de informação baseados na tecnologia Web (SIW) possuem características que permitem supor que seu desenvolvimento apresenta diferenças com relação ao de sistemas não Web. O objetivo desta pesquisa foi levantar, através de um estudo exploratório de múltiplos casos, as questões relevantes ao desenvolvimento de sistemas de informação baseados na tecnologia Web que apóiam aplicações de negócios nas organizações. Para tanto, procuramos identificar as principais dificuldades e facilidades, as alterações sucedidas nas tarefas e na estrutura do desenvolvimento, assim como analisar a adoção de técnicas e metodologias. Esperamos ter contribuído para que as organizações possam aprimorar o desenvolvimento de SIW de forma a aproveitar ao máximo as oportunidades criadas pela tecnologia Web. / The Web technology was created to divulge the scientific knowledge, although it has been used as a way to access several types of business information systems as well as to facilitate the communication between them, generating many business opportunities for the organizations. Web-based information systems (WIS) have characteristics that allow us to assume their development is different from non-Web information systems. The objective of this research was to identify, through an exploratory multi-case study, the main questions about business Web-based information systems development. We have tried to identify the main difficulties and easiness, the changes occurred in development tasks and structure, and to analyze techniques and methodologies adoption. We hope we had contributed to allow organizations be able to improve the WIS development process in order to take the maximum advantage of the opportunities generated by Web technology.

This research focuses on the development of a new methodology for creating effective websites, especially those used for marketing. It was found that existing methodologies were missing some key stages - user participation and “real interaction” (i.e. monitoring of user interaction with a prototype site). This has led to users being frustrated and lacking loyalty to the website. There is great potential for combining aspects of methodologies from different disciplines; however, these need to be integrated in a coherent way. To address these problems, a new integrated methodology was developed in this research. The new methodology was created from basic concepts derived from: lifecycle models; Information Systems development methodologies; methodologies with explicit human factors aspects; websites methodologies; marketing methodologies; and additional techniques such as task analysis and detailed website design and implementation. After studying the lifecycle model, the researcher identified four key principles, which were the foundation of the research: user participation; iteration; usability and “real interaction”. The way in which these four principles were incorporated in each methodology was evaluated in order to choose the strongest stages to utilize in the new combined methodology. After reviewing techniques for methodology integration, a new draft methodology was produced. To assess the new methodology, two research phases were used - interviews and a questionnaire. In the former phase, the researcher interviewed representatives from nine website development companies in Western Australia to discuss their current methodologies and compared these with the new methodology. / Most of the industry participants were pleased with the structure of the new methodology, as most agreed that it incorporates the necessary requirements to develop a successful website. The interviews generated some recommendations for revisions to the methodology, which assisted the researcher to improve the new methodology. In the latter phase, an online questionnaire was completed by a total of website industry participant andInformation Systems Professionals, in order to assess the revised methodology. Results from the interviews and questionnaire supported the research hypothesis – i.e. that the new integrated methodology can provide a more effective way of developing websites, utilizing the four key principles. This thesis points to the need for further research, including the development of a website describing the new methodology. This website will incorporate a software tool to facilitate selection of particular stages, steps and techniques from theintegrated methodology to produce a tailored methodology for any specific project, thereby implementing the concept of “contingency”.

Recent designs for low-density parity-check (LDPC) codes have exhibited capacity approaching performance for large block length, overtaking the performance of turbo codes. While theoretically impressive, LDPC codes present some challenges for practical implementation. In general, LDPC codes have higher encoding complexity than turbo codes both in terms of computational latency and architecture size. Decoder circuits for LDPC codes have a high routing complexity and thus demand large amounts of circuit area. There has been recent interest in developing analog circuit architectures suitable for decoding. These circuits offer a fast, low-power alternative to the digital approach. Analog decoders also have the potential to be significantly smaller than digital decoders. In this thesis we present a novel and efficient approach to LDPC encoder / decoder (codec) design. We propose a new algorithm which allows the parallel decoder architecture to be reused for iterative encoding. We present a new class of LDPC codes which are iteratively encodable, exhibit good empirical performance, and provide a flexible choice of code length and rate. Combining the analog decoding approach with this new encoding technique, we design a novel time-multiplexed LDPC codec, which switches between analog decode and digital encode modes. In order to achieve this behaviour from a single circuit we have developed mode-switching gates. These logic gates are able to switch between analog (soft) and digital (hard) computation, and represent a fundamental circuit design contribution. Mode-switching gates may also be applied to built-in self-test circuits for analog decoders. Only a small overhead in circuit area is required to transform the analog decoder into a full codec. The encode operation can be performed two orders of magnitude faster than the decode operation, making the circuit suitable for full-duplex applications. Throughput of the codec scales linearly with block size, for both encode and decode operations. The low power and small area requirements of the circuit make it an attractive option for small portable devices.

Problem statement: There seem to be perceptual incongruence between systems development managers and developers. Research shows that while managers are more positive towards systems development methodologies, developers on the other hand seem to resist and not to use systems development methodologies in their entirety but instead adapt, tailor, modify and change them depending on the project at hand (contingent use). Systems development managers can exert power through a variety of influence bases. However, these power influences may be perceived differently by developers. While some might feel constrained, others might actually feel liberated by the existence of the same influence base. Main findings: IS managers are using systems development methodologies to gain control over team members. However, there was no clear perception on whether systems development methodologies were enslaving systems developers. This was indicated by the majority of the respondents neither agreeing nor disagreeing to that effect. The research showed that most organisations are adapting the use of systems development methodologies on a project to project basis, which is referred to as the contingent use of systems development methodologies. Research method followed: The positivistic research paradigm was used as it allowed the researcher to find out patterns and regularities between power, systems development methodologies’ use and success. A survey was conducted and a questionnaire was used for data collection purposes. Questionnaire data was analysed using IBM SPSS Statistics Version 21, Release 20.0.0 software package tools. Principal conclusion: Power is interpreted in terms of the type of power that can be exercised by IT professionals specifically IS developers and their respective managers at the workplace. The roles assumed and the different power types that may be exercised in organisations provide a link as to who has the final say when it comes to the use and success rate of systems development methodologies. The contingent use of systems development methodologies provides a form of “freedom” to systems developers. Based on the research findings, the research proposes an answer to the question – are systems development methodologies enslaving systems developers and empowering IS managers? / MSc (Computer Science), North-West University, Potchefstroom Campus, 2014

Abstract The main focus of this study is the identification of factors influencing the use and effectiveness of information system development methodologies (Le., systems development methodologies) in health information systems. In essence, it can be viewed as exploratory research, utilizing a conceptual research model to investigate the relationships among the hypothesised factors. More specifically, classified as behavioural science, it combines two theoretical models, namely the Unified Theory of Acceptance and Use of Technology and the Expectancy Disconfirmation Theory. The main aim of behavioural science in information systems is to assist practitioners (Le., social actors) in improving business processes and competitiveness, thus the effective use of information systems. A wider view of behavioural science incorporates other social actors (e.g., end users) and organisational actors (e.g., executives). In health information systems, the effective use of information systems is especially relevant Health information systems are vital in the area of health care, since only by having access to pertinent health information, can the correct decisions relating to diagnostics and curative procedures be made. The use of systems development methodologies in health information systems development is therefore crucial, since they can make the development process more effective, while improving software quality. By empirically evaluating the conceptual research model, utilizing a survey as the main research method and structural equation modelling as the main statistical technique, meaningful results were obtained. Focussing on the factors influencing the individual's behavioural intent, it was found that the compatibility of systems development methodologies to the developer's pre-existing software development style is vital. Furthermore, performance expectancy, self-efficacy, organisational culture, policies, customer influence, voluntariness and facilitating conditions, all directly influenced the use of systems development methodologies, with policies and customer influence playing a significant role, especially in relation to health information systems. No significant direct effects or indirect effects could be established for the factors effort expectancy, personal innovativeness and social influence. It appears that individuals working in the health care software development discipline are more autonomous, less influenced by others. Also, the lack of support for the factor effort expectancy may indicate that systems development methodologies have entered a mature state, with less concern on the effort required for use. Furthermore, with regard to effectiveness and the continued use of information systems methodologies, satisfaction had a significant direct effect, with confirmation having a significant indirect effect. Keywords: behavioural science; conceptual research model; direct effect; exploratory research; Expectancy Disconfirmation Theory; indirect effect; Unified Theory of Acceptance and Use of Technology; structural equation modelling; survey; systems development methodologies. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2010.

Abstract The main focus of this study is the identification of factors influencing the use and effectiveness of information system development methodologies (Le., systems development methodologies) in health information systems. In essence, it can be viewed as exploratory research, utilizing a conceptual research model to investigate the relationships among the hypothesised factors. More specifically, classified as behavioural science, it combines two theoretical models, namely the Unified Theory of Acceptance and Use of Technology and the Expectancy Disconfirmation Theory. The main aim of behavioural science in information systems is to assist practitioners (Le., social actors) in improving business processes and competitiveness, thus the effective use of information systems. A wider view of behavioural science incorporates other social actors (e.g., end users) and organisational actors (e.g., executives). In health information systems, the effective use of information systems is especially relevant Health information systems are vital in the area of health care, since only by having access to pertinent health information, can the correct decisions relating to diagnostics and curative procedures be made. The use of systems development methodologies in health information systems development is therefore crucial, since they can make the development process more effective, while improving software quality. By empirically evaluating the conceptual research model, utilizing a survey as the main research method and structural equation modelling as the main statistical technique, meaningful results were obtained. Focussing on the factors influencing the individual's behavioural intent, it was found that the compatibility of systems development methodologies to the developer's pre-existing software development style is vital. Furthermore, performance expectancy, self-efficacy, organisational culture, policies, customer influence, voluntariness and facilitating conditions, all directly influenced the use of systems development methodologies, with policies and customer influence playing a significant role, especially in relation to health information systems. No significant direct effects or indirect effects could be established for the factors effort expectancy, personal innovativeness and social influence. It appears that individuals working in the health care software development discipline are more autonomous, less influenced by others. Also, the lack of support for the factor effort expectancy may indicate that systems development methodologies have entered a mature state, with less concern on the effort required for use. Furthermore, with regard to effectiveness and the continued use of information systems methodologies, satisfaction had a significant direct effect, with confirmation having a significant indirect effect. Keywords: behavioural science; conceptual research model; direct effect; exploratory research; Expectancy Disconfirmation Theory; indirect effect; Unified Theory of Acceptance and Use of Technology; structural equation modelling; survey; systems development methodologies. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2010.

Recent designs for low-density parity-check (LDPC) codes have exhibited capacity approaching performance for large block length, overtaking the performance of turbo codes. While theoretically impressive, LDPC codes present some challenges for practical implementation. In general, LDPC codes have higher encoding complexity than turbo codes both in terms of computational latency and architecture size. Decoder circuits for LDPC codes have a high routing complexity and thus demand large amounts of circuit area. There has been recent interest in developing analog circuit architectures suitable for decoding. These circuits offer a fast, low-power alternative to the digital approach. Analog decoders also have the potential to be significantly smaller than digital decoders. In this thesis we present a novel and efficient approach to LDPC encoder / decoder (codec) design. We propose a new algorithm which allows the parallel decoder architecture to be reused for iterative encoding. We present a new class of LDPC codes which are iteratively encodable, exhibit good empirical performance, and provide a flexible choice of code length and rate. Combining the analog decoding approach with this new encoding technique, we design a novel time-multiplexed LDPC codec, which switches between analog decode and digital encode modes. In order to achieve this behaviour from a single circuit we have developed mode-switching gates. These logic gates are able to switch between analog (soft) and digital (hard) computation, and represent a fundamental circuit design contribution. Mode-switching gates may also be applied to built-in self-test circuits for analog decoders. Only a small overhead in circuit area is required to transform the analog decoder into a full codec. The encode operation can be performed two orders of magnitude faster than the decode operation, making the circuit suitable for full-duplex applications. Throughput of the codec scales linearly with block size, for both encode and decode operations. The low power and small area requirements of the circuit make it an attractive option for small portable devices.

With the evolution of Information Technology, especially the Internet, system integration is becoming a common way to expand IT systems within and beyond an enterprise network. Although system integration is becoming more and more common within large organizations, however, the literature review had found IS research in this area had not been sufficient, especially for the development of integration solutions within large organizations. It has made research like this one conducted within a large NZ government agency necessary. Four system integration projects were selected and studied using case study research methodology. The case study was designed and conducted using guidelines mainly from the well-known R. K. Yin’s (2002) “Case Study Research” book. The research was set to seek answers for a series of research questions, which were related to requirements of system integration and challenges for solution development. Special attention had been given to XML applications, as system integration and XML were found to be coupled in many system integrations and frameworks during the literature review. Data were first gathered from all four projects one by one, and then the bulk of analysis was done on the summarized data. Various analysis methods including chain-of-evidence, root-cause-analysis and pattern-matching were adopted. The principles of interpretive research proposed by Klein and Myers (1999) and triangulation were observed. In conclusions, a set of models have been derived from the research, namely a model for clarifying integration requirements; a model for integration solution architecture; a model for integration development life cycle and a model of critical success factor for integration projects. A development framework for small to medium size integration projects has also been proposed based on the models. The research also found XML application indeed would play an important role for system integration; the critical success factors for XML application included suitable development tools, development skills and methodologies.

The key objective of this research is to develop a selection methodology that can be used to support and aid the selection of development processes for e-Commerce Information Systems (eCIS) effectively using various decision methods. The selection methodology supports developers in their choice of an e-Commerce Information System Development Process (e-Process) by providing them with a few different decision making methods for choosing between defined e-Processes using a set of quality aspects to compare and evaluate the different options. The methodology also provides historical data of previous selections that can be used to further support their specific choice. The research was initiated by the fast growing Information Technology environment, where e-Commerce Information Systems is a relatively new development area and developers of these systems may be using new development methods and have difficulty deciding on the best suited process to use when developing new eCIS. These developers also need documentary support for their choices and this research helps them with these decision-making processes. The e-Process Selection Methodology allows for the comparison of existing development processes as well as the comparison of processes as defined by the developers. Four different decision making methods, the Value-Benefit Method (Weighted Scoring), the Analytical Hierarchy Process, Case-Based Reasoning and a Social Choice method are used to solve the problem of selecting among e-Commerce Development Methodologies. The Value-Benefit Method, when applied to the selection of an e-Process from a set of e-Processes, uses multiple quality aspects. Values are assigned to each aspect for each of the e-Processes by experts. The importance of each of the aspects, to the eCIS, is defined in terms of weights. The selected e-Process is the one with the highest score when the values and weights are multiplied and then summed. The Analytic Hierarchy Process is used to quantify a selection of quality aspects and then these are used to evaluate alternative e-Processes and thus determining the best matching solution to the problem. This process provides for the ranking and determining of the relative worth of each of the quality aspects. Case-Based Reasoning requires the capturing of the resulting knowledge of previous cases, in a knowledge base, in order to make a decision. The case database is built in such a way that the concrete factual knowledge of previous individual cases that were solved previously is stored and can be used in the decision process. Case-based reasoning is used to determine the best choices. This allows the user to either use the selection methodology or the case base database to resolve their problems or both. Social Choice Methods are based on voting processes. Individuals vote for their preferences from a set of e-Processes. The results are aggregated to obtain a final result that indicates which e-Process is the preferred one. The e-Process Selection Methodology is demonstrated and validated by the development of a prototype tool. This tool can be used to select the most suitable solution for a case at hand. The thesis includes the factors that motivated the research and the process that was followed. The e-Process Selection Methodology is summarised as well as the strengths and weaknesses discussed. The contribution to knowledge is explained and future developments are proposed. To conclude, the lessons learnt and reinforced are considered.