Radical polymerisation (RP) has for many years been an industrially important process, and the kinetics of the process remains an active area of research. As polymerisation proceeds, converting monomer (small molecules) into polymer (long chain molecules), chemical species of a variety of chain lengths are produced. Recent work has pointed toward the fact that rate coefficients for polymerisation reactions (specifically, termination and propagation) are often dependent on the chain-length of the reacting species. The focus of this thesis is to study the effects of chain-length-dependent reactions on the kinetics of RP, by using computer-based modeling and comparing the results of such modeling with experimental data. This enables the understanding of otherwise inexplicable trends and the building of more mechanistically detailed and accurate models for RP kinetics. In Chapter 2, a new model for termination is developed, connecting observations and analyses of termination kinetics at short chain lengths (particularly small molecule studies) with other observations and analyses at long chain lengths (conventional RP kinetics studies) in order to construct a model for termination that is shown to be capable of coherently describing termination kinetics at any chain length. In Chapter 3, this new model for termination is tested at short chain lengths on polymerisations with large quantities of added chain transfer agent. With the inclusion of chain-length-dependent propagation in the model, the model for termination is validated. Chapter 4 is aimed at extending an existing reduced-variable, compact, 'universal' description of steady-state RP kinetics by incorporating all known chain-length dependent reactivities. This both increases computational efficiency over other approaches and provides easily evaluated, approximate analytical expressions for RP kinetics. This foundational theory is applied in Chapter 5 to reach a deeper understanding of the behaviour of the model, and show how experimental data may readily be analysed to extract information about chain-length-dependent termination kinetics. In Chapter 6, the effect of chain-length dependent reactivities on the important technique of single-pulse pulsed-laser polymerisation is investigated, and this technique is validated as the best experimental method for investigation of termination kinetics. In general, a central result of this thesis is that chain-length-dependent reactivities, when acknowledged and properly incorporated into models, can explain many phenomena in RP kinetics which otherwise seem difficult to account for. No exceptions to this principle have been found.

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This thesis investigates the effects of in-application relaxation and memory technique instructions on effectiveness of human–computer interaction (HCI) in a computer-based learning (CBL) set-up. The literature survey identifies a general absence of a clear definition of effectiveness of human–computer interaction, and even more scarcity of direct reference to the connection between effectiveness of human–computer interaction and learning.

Polyhedra have been the subject of fascination and interest to mathematicians, philosophers and artists since the ancient times. Forms based on polyhedra have subsequently become popular with engineers and architects. However, data generation for these polyhedric configurations has traditionally been a barrier to advancement in this area. Graphical based solutions have been applied which have severely limited the scope of the applications. The objective of the present work is to facilitate the creation of forms based on polyhedral, and so broaden the boundaries as to what is achievable. To this end the work is concerned with the development and implementation of the concepts in a computer based environment. In order for this to be achieved three key elements are required for each polyhedron. They are as follows; o Establishment of a coordinate system, o Evolution of a set of conventions for assigning identity numbers for faces, edges and vertices of polyhedra, and o Establishment of an orientation system for mapped objects. These have been developed to be compatible within the computer based environment. The implementation of the concepts is through the 'polymation function', which has been created to be a standard function within the programming language Formian. A series of other functions, complementary to the polymation function have been developed to be used within Formian. The most prominent of these is the 'tractation function' which is used to project configurations onto a range of surfaces, including a user-defined surface. The work includes a look at some of the forms which may be created using the new tools, particularly in the area of 'geodesic' forms. Suggestions for future research in this field include widening the range of polyhedra available, looking at the problem of 'mitring', exploring rendering techniques and the development of a more general function which could encompass user-defined polyhedra.

The idea that computers are important as an aid to learning has gathered momentum due to ecomomic and social conditions. Moreover, the number and flexibility of computer hardware and software has lead to them being used at all levels of education, from primary school to higher education. This is learning at a distance as it involves no direct contact with the teacher in the traditional sense. This study, which is in the form of a formative evaluation, involves computer-based aids used to deliver commercial packages and reading lists in information and library studies topics. The evaluations involved tutors, academic librarians and students at all levels; research and undergraduate. Staff and students from Loughborough University and the Department of History at Leicester University were participants, as well as tutors and academic librarians from various British universities. To complete the study, questionnaires and interview questions were designed to reflect the backgrounds of participants, their views on the success, or otherwise, of the aids and their views on computer-based learning in general. Quantitative and qualitative techniques were to determine outcomes. Commercial packages were highlighted and some comparison was made between staff and students with regard to outcomes. Features which were more successful were identified, and information was gathered on how students use automated reading lists. The value of this study is two-fold. First, it brings forward information which can be used to improve computert-based learning and, second, it pinpoints the situation as it was during the years of evolution, i.e. 1992-1996.

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This dissertation aims to identify undergraduate students' perspectives concerning the effectiveness of CBI environments as an instructional tool, and the influence it has on their self-efficacy and motivation. Data was collected from 221 participants from two midwestern universities. A convergent mixed-method research was conducted using a Likert-style survey and semistructured interviews. Stepwise regression, Pearson correlation coefficient, effect sizes and thematic analysis were used to identify significant relationships between variables, and find recurring themes. It was found that over 70% of the student population had positive attitudes towards the use of CBI environments with a mean of 3.5 on a 5-point scale. Students who had a high mean attitude towards CBI systems also had a high mean self-efficacy score. Secondly, four models emerged which suggests that; the value student assign to tasks, the control over the CBI environment, control over their learning, and motivation are significant factors (p>.50) that affect their self-efficacy. Finally, it was found that students' motivation is affected by instructional components, challenges, lack of instructor presence, and feedback. It can be concluded that varying factors that can affect how students' perceive the courses and their abilities, and the implementation of adaptive CBI systems maybe an option to meet students' diverse instructional needs. Future research recommendations are (1) if professors pacing of activities within a CBI affect students' self-efficacy when course semesters vary, and (2) if the lack of professor control over activity design negatively impacts students learning and motivation.

Distance education (DE) can address barriers to training nutrition professionals by offering a convenient, flexible and efficient way of learning. One particularly valuable teaching tool in DE is the use of computer-based simulations (CBS). CBS stimulates confidence building, acquisition of new knowledge, exposure to new and challenging patient cases in a safe learning environment, development of communication and critical thinking skills, and the cultivation of sensitivity towards patient needs. Despite the benefits, there is a lack of research examining dietetic educator’s perceptions of and experience with CBS. Goals of this study were to determine: 1) whether dietetic program educators were open to the idea of using CBS and how these responses varied in relation to different factors, and 2) dietetic program educators’ perceptions of the benefits and barriers of using CBS. Secondary data analyses were conducted on a15-item survey developed by the American Dietetic Association (ADA). Surveys contained two qualitative questions and 13 quantitative questions related to CBS. Surveys were e-mailed via the ADA listserv to 535 program directors, including Dietetic Internship Programs (DI), Coordinated Programs in Dietetics (CP), Didactic Programs in Dietetics (DPD), and the Dietetic Technician Programs (DT). A total of 165 individuals responded to the survey. The majority of respondents were open to the use of CBS (n=117) and a small number were not open (n=24). Respondents open to CBS were more likely to 1) not prefer face-to-face communication with their students and colleagues 2) currently be using online case studies and simulations 3) be using standardized patients in supervised practice 4) believe that dietetics education needs alternatives to traditional supervised practice such as CBS 5) believe that they have IT and financial support from their administration 6) have medical simulation laboratories available for dietetics students 7) believe that they had the technological skills needed to use CBS. Educators commented on the potential for CBS to address the shortage of preceptors and facilities available for supervised practice, in addition to enhancing and expediting learning in various settings. Perceived barriers, included the idea that technology impedes learning and a concern about the resources needed to implement CBS. Understanding the perspectives and practices of education program directors is a crucial component of furthering the process of incorporating CBS into nutrition education. This is exciting new terrain for nutrition education and moving forward with research in both distance education and CBS will be beneficial to enhancing nutrition and dietetics education in DE, traditional classroom settings and in supervised practice.

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The following report discusses the design and formative evaluation of a prototype for a computer-based course to teach speech acts as part of the Technology Assisted Language Learning (TALL) program. The report includes a literature review on speech acts and current methods and strategies for language teaching and instructional design. Next, there is a description of the lessons and the design process, as well as a summary of the formative evaluation. Following is the prototype of the lesson on apologies. The report concludes with a discussion of the project's limitations and suggestions for future research.