Avaliação de sistemas de informação e frames tecnológicos (estruturas cognitivas compartilhadas em relação à tecnologia) constituem-se as temáticas focais desta pesquisa cujo objetivo foi compreender como se estabelece a relação entre processos de avaliação formais e informais de um sistema de informação e frames tecnológicos. A estrutura de avaliação conteúdo-contexto-processo e o arcabouço teórico de frames tecnológicos, especialmente seus elementos constitutivos - conhecimentos, pressupostos e expectativas - foram associados visando a esta compreensão. A pesquisa foi realizada em uma instituição de ensino superior e o objeto de estudo tratou-se de um sistema de informação acadêmico (Peoplesoft), implementado e em uso nesta instituição. Especificamente analisaram-se: avaliações formais e informais do sistema acadêmico em relação à estrutura conteúdo-contexto-processo; a natureza e extensão de diferenças em frames tecnológicos de grupos sociais distintos; e como frames tecnológicos moldam e são moldados por avaliações formais e informais de um sistema de informação. Com pressupostos epistemológicos sustentados pela perspectiva interpretativista, metodologicamente o estudo caracterizou-se por uma abordagem qualitativa do tipo estudo de caso único e incorporado (grupos sociais como sub-unidades de análise). Entrevistas em profundidade, observação participante, revisão documental e artefato físico constituíram-se as fontes de dados empíricos. Adotaram-se os fundamentos do método hermenêutico-dialético para a análise e interpretação dos dados coletados. O estudo propiciou identificar que: frames tecnológicos e avaliações do sistema de informação, sejam formais ou informais, influenciam-se reciprocamente; características pessoais, contextuais e tecnológicas integram-se criando, reforçando e modificando frames tecnológicos; diferentes avaliações sobre o sistema acadêmico são socialmente construídas pelos indivíduos inseridos em grupos sociais e fortemente afetadas pelo que acreditam, conhecem e esperam deste sistema; frames tecnológicos manifestam-se tanto no conteúdo da avaliação quanto no processo avaliativo, influenciando a identificação de fatores do conteúdo assim como o teor do julgamento destes fatores, o modo pelo qual se avalia e o próprio contexto da avaliação; em contrapartida, processos de avaliações informais, decorrentes da interação social, afetam frames tecnológicos; nestes processos, conhecimentos prévios são validados, ampliados ou refutados, pressupostos e expectativas criados e recriados; igualmente, o modo como avaliações formais são configuradas desencadeia conhecimentos, pressupostos e expectativas sobre a tecnologia. / Information systems evaluation and technological frames (shared cognitive structures that relate to technology) are the main themes of this research. Its general goal has been to establish how the relationship between formal and informal processes of information systems evaluation and technological frames operates. The structure of evaluation (content-context-process) and the theoretical stance of the technological frames, especially in respect to its constitutive elements, have been analyzed and linked to each other. The research has been conducted in a graduate institution and its object of analysis, a software called \"Peoplesoft\", which was already implemented and that is in use nowadays. Specific analysis deal with the following topics: a) both formal and informal evaluations of the information system in relation to the \"content-context-process\" structure; the nature and extension of the differences that sustain technological frames for different groups as well how these technological frames are molded and formed by formal and informal assessment (evaluations) of such system. Epistemological suppositions were held by an interpretative perspective while, methodologically, this study is characterized by a qualitative perspective of a unique case in which social groups act as sub-units of analysis. In-depth interviews, paticipative observations, documental review and physical artifacts have been the sources of empirical data. Data analysis and interpretation has been backed up by a dialectic-hermeneutic method. The results point to reciprocal influences between technological frames and information systems evaluations (both formal and informal ones). Personal and contextual characteristics as well as technological ones are integrated creating, reinforcing and modifying technological frames. Thus, different evaluations of the academic information system are socially constructed by the individuals and become greatly affected by their prior knowledge of the system, their assumptions and expectations towards it. Technological frames manifest themselves in relation to both the content and processes of evaluation, thus influencing the identification of generating factors of such judgments, as well as their substance; frames also influence the manners how evaluations are made and the context where they take place. On the other hand, informal evaluation processes, the product of social interaction, affect technological frames. In these processes, previous knowledge is validated, amplified or refuted; assumptions and expectations are created and/or recreated. At the same time, the ways in which formal evaluations are proposed trigger certain knowledges, expectations and assumptions about technology.

This thesis assesses the effectiveness of the National Prevention of Mother to Child Transmission of HIV (PMTCT) programme in 3 sites in South Africa, and the quality of infant feeding counselling across four countries, Botswana, Kenya, Malawi and Uganda . Implementation and outcome of PMTCT services were very different across the 3 sites. The Paarl site is achieving results comparable to clinical trial studies with a HIV-free survival rate of 85% at 36 weeks, while Umlazi is somewhat lower (74%) and Rietvlei, with HIV-free survival of 64%. Maternal viral load, prematurity and site were independent risk factors for infection and/or death. The regression analysis suggests that some of this difference is explained by the differences in quality of health systems across the sites. Traditional risk factors (e.g. viral load, prematurity) do not seem to explain the substantial differences in HIV-free survival between the Paarl and Rietvlei sites. The overall mortality rate for HIV exposed infants in this cohort was 155 per 1000 live births at 36 weeks, a level higher than most other HIV exposed cohorts. The excess mortality is occurring almost completely amongst HIV infected infants who had a nine fold increased risk of mortality compared with HIV exposed but HIV negative infants. There was no significant difference in 36 week survival rates between those HIV exposed but uninfected infants and those who were not HIV exposed, Hazard ratio 0.7 (95% CI 0.3-1.5). With respect to HIV and infant feeding most health workers across the four countries (234/334, 70%) were unable to correctly estimate the transmission risks of breastfeeding. Exposure to PMTCT training made little difference to this. Infant feeding options were mentioned in 307 out of 640 (48%) observations of PMTCT counselling session and in only 35 (5.5%) were infant feeding issues discussed in any depth; of these 19 (54.3%) were rated as poor. South Africa was similar with only two out of thirty four HIV positive mothers being asked about essential conditions for safe formula feeding before a decision was made. This body of work has demonstrated that the gap between efficacy and effectiveness can be significant.

Generative Multimedia (GM) applications are an increasingly popular way to implement interactive media performances. Our contributions include creating a metric for evaluating Generative Multimedia performances, designing a model for accepting perceiver preferences, and using those preferences to adapt GM performances. The metric used is imprecision, which is the ratio of the actual computation time of a GM element to the computation time of a complete version of that GM element. By taking a perceiver's preferences into account when making adaptation decisions, applications can produce GM performances that meet soft real-time and resource constraints while allocating imprecision to the GM elements the perceiver least cares about. Compared to other approaches, perceiver-directed imprecision best allocates impreciseness while minimizing delay.

The research reported in this thesis is focused on some of the implications for Library and Information Science of the development of the Internet, and the World-Wide Web (WWW) in particular. It highlights the need for a wider involvement of this profession in the better management, organisation, and ultimately - usability, of the global information system. An extensive study of the information seeking process was carried out on a collection of interlinked hypertext documents constituting a PC-based model of the World-Wide Web. Special attention was paid to the correlation of WWW document authoring characteristics and the success rate in browsing sessions performed by novice, casual and experienced Internet end-users. The analysis of the results from a number of browsing sessions on the model led to some specific recommendations for comprehension-oriented WWW authoring. / Thesis (M.I.S.)-University of Natal, Pietermaritzburg, 1997.

A number of approaches of assessment associated with IS effectiveness have been examined, fundamental guidelines for research in this area have been derived, and a novel model of IS effectiveness has been proposed. A process based assessment method (PB-ISAM) based on the proposed effectiveness model has been elaborated. The new model and the new assessment method have been evaluated via three case studies. Specific implications have been drawn concerning the relationships between processes and the information system assessed. The three case studies have provided insight into the IS effectiveness field and for future work.

Avaliação de sistemas de informação e frames tecnológicos (estruturas cognitivas compartilhadas em relação à tecnologia) constituem-se as temáticas focais desta pesquisa cujo objetivo foi compreender como se estabelece a relação entre processos de avaliação formais e informais de um sistema de informação e frames tecnológicos. A estrutura de avaliação conteúdo-contexto-processo e o arcabouço teórico de frames tecnológicos, especialmente seus elementos constitutivos - conhecimentos, pressupostos e expectativas - foram associados visando a esta compreensão. A pesquisa foi realizada em uma instituição de ensino superior e o objeto de estudo tratou-se de um sistema de informação acadêmico (Peoplesoft), implementado e em uso nesta instituição. Especificamente analisaram-se: avaliações formais e informais do sistema acadêmico em relação à estrutura conteúdo-contexto-processo; a natureza e extensão de diferenças em frames tecnológicos de grupos sociais distintos; e como frames tecnológicos moldam e são moldados por avaliações formais e informais de um sistema de informação. Com pressupostos epistemológicos sustentados pela perspectiva interpretativista, metodologicamente o estudo caracterizou-se por uma abordagem qualitativa do tipo estudo de caso único e incorporado (grupos sociais como sub-unidades de análise). Entrevistas em profundidade, observação participante, revisão documental e artefato físico constituíram-se as fontes de dados empíricos. Adotaram-se os fundamentos do método hermenêutico-dialético para a análise e interpretação dos dados coletados. O estudo propiciou identificar que: frames tecnológicos e avaliações do sistema de informação, sejam formais ou informais, influenciam-se reciprocamente; características pessoais, contextuais e tecnológicas integram-se criando, reforçando e modificando frames tecnológicos; diferentes avaliações sobre o sistema acadêmico são socialmente construídas pelos indivíduos inseridos em grupos sociais e fortemente afetadas pelo que acreditam, conhecem e esperam deste sistema; frames tecnológicos manifestam-se tanto no conteúdo da avaliação quanto no processo avaliativo, influenciando a identificação de fatores do conteúdo assim como o teor do julgamento destes fatores, o modo pelo qual se avalia e o próprio contexto da avaliação; em contrapartida, processos de avaliações informais, decorrentes da interação social, afetam frames tecnológicos; nestes processos, conhecimentos prévios são validados, ampliados ou refutados, pressupostos e expectativas criados e recriados; igualmente, o modo como avaliações formais são configuradas desencadeia conhecimentos, pressupostos e expectativas sobre a tecnologia. / Information systems evaluation and technological frames (shared cognitive structures that relate to technology) are the main themes of this research. Its general goal has been to establish how the relationship between formal and informal processes of information systems evaluation and technological frames operates. The structure of evaluation (content-context-process) and the theoretical stance of the technological frames, especially in respect to its constitutive elements, have been analyzed and linked to each other. The research has been conducted in a graduate institution and its object of analysis, a software called \"Peoplesoft\", which was already implemented and that is in use nowadays. Specific analysis deal with the following topics: a) both formal and informal evaluations of the information system in relation to the \"content-context-process\" structure; the nature and extension of the differences that sustain technological frames for different groups as well how these technological frames are molded and formed by formal and informal assessment (evaluations) of such system. Epistemological suppositions were held by an interpretative perspective while, methodologically, this study is characterized by a qualitative perspective of a unique case in which social groups act as sub-units of analysis. In-depth interviews, paticipative observations, documental review and physical artifacts have been the sources of empirical data. Data analysis and interpretation has been backed up by a dialectic-hermeneutic method. The results point to reciprocal influences between technological frames and information systems evaluations (both formal and informal ones). Personal and contextual characteristics as well as technological ones are integrated creating, reinforcing and modifying technological frames. Thus, different evaluations of the academic information system are socially constructed by the individuals and become greatly affected by their prior knowledge of the system, their assumptions and expectations towards it. Technological frames manifest themselves in relation to both the content and processes of evaluation, thus influencing the identification of generating factors of such judgments, as well as their substance; frames also influence the manners how evaluations are made and the context where they take place. On the other hand, informal evaluation processes, the product of social interaction, affect technological frames. In these processes, previous knowledge is validated, amplified or refuted; assumptions and expectations are created and/or recreated. At the same time, the ways in which formal evaluations are proposed trigger certain knowledges, expectations and assumptions about technology.

There is a need in classrooms to engage students and maintain their interest in course content. A recent type of interactive technology, known as a "clicker," has shown potential to increase student engagement, performance, and participation in the classroom when used effectively. Peer instruction, a type of student to student interaction in which pairs or small groups of students discuss their answers to questions before responding, is often used in conjunction with clickers, and may account for the perceived effectiveness of these tools. The purpose of this study is to determine the clicker's effectiveness in increasing learning and increasing student engagement in secondary classrooms, while controlling for their use during peer instruction. Two classrooms were examined (n ~ 15 for each classroom) in which 1 classroom used clickers integrated with peer instruction activities, while the other classroom only did the peer instruction activities. The findings of this study showed no significant difference in student learning, a small increase in student engagement, and a positive student reaction to the clicker's potential and use in the classroom.

This research tested the effect of unique combinations of interface coding and presentation techniques for the redesign of the AN/SLQ-32(V) Display Control Console (DCC). The DCC provides Navy operators with bearing and threat information for radar emitters. The task of emitter identification was used to test potential redesigns. There is no research to substantiate the current or possible redesign solutions. Thus, Experiment 1 tested potential design modifications for the DCC. The factorial combination of the following comparisons yielded eight possible design solutions: color versus monochrome coding, polar (bearing only) versus range (bearing and range) presentation, and geometric symbols versus icons. Each design was tested in three conditions of emitter density: low, medium, and high. Researchers have evaluated color and symbology with consideration to emitter display systems, but without considering how range information and emitter density effect performance. Results indicate that range information improves performance by 60%. The addition of color and the new icons also significantly improves performance (17% and 15%, respectively) as compared to the current DCC configuration (Polar, Geometric, and Monochrome). Performance was measured by time to complete a task, errors, and subjective workload. Experiment 2 considered redesign solutions not restricted to the existing hardware or software. Although discussed frequently in the interface literature, performance differences between direct-manipulation and command-key interfaces have not been validated. In this study, two interfaces were constructed to take advantage of direct manipulation and command-key interaction (DMI and CKI, respectively) styles while adding a computer-aided emitter library management system, an on-screen oscilloscope, a polygon display of emitter parameters, range information, icons, increased usage of color, and other design changes. Results indicate no differences between the CKI and DMI for the time required to perform the task or for subjective workload. Although both interfaces were designed to take advantage of their respective features, operators did not perform faster with the CKI than with the DMI. However, operators did have significantly fewer errors with the DMI than with the CKI. When compared to the existing DCC and the Range/Color/Iconic design, operators using the CKI and DMI: (1) processed twice as many emitters, (2) reduced one type of error by 50% (CKI) or 67% (DMI), (3) reduced a second type of error to zero, (4) decreased subjective workload by over 50%, and (5) maintained a higher level of performance regardless of emitter density. / Ph. D.

The present research incorporated the content of basic statistics into the Artificial Intelligence Physics Tutor (ARPHY), which was used as the expert system shell, and investigated the effects of the Artificial Intelligent Statistics Tutor (ARSTAT) as a supplement to learning statistics at the college level. Two classes of an introductory educational statistics course in the Department of Educational Foundations, University of North Texas, were used in the study. The daytime class was used as the experimental group and the evening class was used as the control group. The experimental group's lecture/discussion was supplemented with ARSTAT, and the control group received only lecture/discussion. A one-way analysis of covariance was used to compare students' test scores. No significant difference was found; however, the adjusted mean score of the experimental group was slightly higher than that of the control group. A two-way analysis of covariance showed no significant main effect or interaction between gender and study technique. A second two-way analysis of covariance showed no significant interaction between the students' attitude toward statistics and the study technique used. However, the students with a statistics-positive attitude scored significantly higher on the test than students who had a negative attitude toward statistics. This study concluded that the ARSTAT can be used effectively as a tutor for students taking an introductory course in educational statistics. The following recommendations for further study were made: incorporate more advanced topics of statistics into the ARPHY teaching model; incorporate the ARPHY learning theory and statistical content using another version of LISP language or another programming language such as PROLOG; and compare the ARSTAT tutor to some other kind of supplement to lecture/discussion.

M. Tech. (Information Technology, Faculty of Applied and Computer Sciences) Vaal University of Technology / A reliable and efficient information system (IS) is critical for Eskom so that it is able to manage and meet its energy demands. A reliable power supply provides stakeholders with the confidence that supply of power is managed sustainably, effectively and efficiently. Thus, an information system is integral in the effective and efficient generation, distribution and transmission of electricity. The purpose of the study was to investigate IS evaluation criteria and to develop a comprehensive framework that will serve as basis for IS evaluation across Eskom. The research study additionally investigated IS evaluation methods and instruments that are currently used in Eskom. This study produced an information systems success evaluation framework. The proposed model was built by reviewing well-established information systems success models and information systems theories found in the literature. This research study followed the interpretive research paradigm combining it with qualitative case study. The research findings linked information systems success to top management support, change management process and information quality. The findings of the study alsorevealed that quality of IS department’s service as perceived by users can greatly influence IS success. The results of this study provided enlightening reference benefit for Eskom, which was in line with Eskom’s goal of improving business processes, efficiencies and eliminating waste.