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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Improving the quality of software design through pattern ontology

Boyer, Marc Guy 31 August 2011 (has links)
Software engineers use design patterns to refactor software models for quality. This displaces domain patterns and makes software hard to maintain. Detecting design patterns directly in requirements can circumvent this problem. To facilitate the analogical transfer of patterns from problem domain to solution model however we must describe patterns in ontological rather than in technical terms. In a first study novice designers used both pattern cases and a pattern ontology to detect design ideas and patterns in requirements. Errors in detection accuracy led to the revision of the pattern ontology and a second study into its pattern-discriminating power. Study results demonstrate that pattern ontology is superior to pattern cases in assisting novice software engineers in identifying patterns in the problem domain.
282

L’analogie de l’hérédité culturelle : fondements conceptuels de la théorie de la double hérédité

Côté Charbonneau, Mathieu 03 1900 (has links)
Selon la théorie de la double hérédité, les processus de transmission sociale des connaissances permettraient aux cultures humaines d'évoluer de manière darwinienne. On parvient à cette conclusion en inférant que, étant donné qu'une analogie profonde peut être établie entre les mécanismes de transmission génétique et ceux de transmission sociale, on devrait non seulement concevoir que les processus cognitifs d'apprentissage social constituent bel et bien un système d'hérédité distinct du système d'hérédité génétique, mais qu’il est aussi légitime, sur la base de cette même analogie, de transférer les concepts explicatifs et outils formels issus de la biologie évolutionnaire et de les adapter à l'étude des cultures humaines en vue de constituer une théorie darwinienne de l'évolution culturelle. Cette analogie de l’hérédité culturelle fait depuis longtemps l'objet de controverses tant au sein de la littérature scientifique que dans les discussions philosophiques. On ne semble pas s'entendre sur la nature même de cette analogie ni non plus sur la force de justification épistémique qu'une telle analogie donnerait à la mise en place d'une théorie darwinienne de l'évolution culturelle. Néanmoins, à travers plus de quarante années de débats, la structure de cette analogie n'a jamais été examinée en détail et on a rarement examiné l'épistémologie des inférences par analogie dans un tel contexte. L'objectif principal de la présente thèse consistera à offrir une première analyse systématique de la nature, de la structure, de la fonction et de la justification épistémique de l'analogie de l'hérédité culturelle, fondement conceptuel de la théorie de la double hérédité. En portant ici une attention particulière à la structure logique de cette analogie, on pourra constater l'ampleur de sa complexité, complexité passant souvent inaperçue dans les critiques de la théorie de la double hérédité. On défendra ici la thèse selon laquelle l'analogie de l'hérédité culturelle est en fait composée de deux analogies constitutives qui, conjointement, ouvrent la voie à la mise en place et à l’organisation d’un programme de recherche visant à mettre au point une théorie darwinienne de l’évolution culturelle. / According to the dual-inheritance theory, processes of social transmission of ideas should allow human cultures to evolve in a Darwinian fashion. This conclusion is obtained by an explanatory inference according to which a profound analogy can be established between the cognitive processes of social learning and those of genetic transmission mechanisms. Not only should we understand social learning as a genuine cultural inheritance system, distinct although complementary to the genetic inheritance system, but, on the basis of the very same analogy, it would also be legitimate to transfer and adapt the theoretical concepts, explanatory formats and formal tools of evolutionary biology to the study of cultural dynamics so as to constitute a Darwinian theory of cultural evolution. The cultural inheritance analogy has been controversial since it was first suggested. A lack of consensus amongst scientists and philosophers about the proper meaning and epistemic reach of such an analogy has impeded the acceptance that human cultures might evolve. Nonetheless, through the forty years of controversy, the structure of the cultural inheritance analogy has never been systematically scrutinized and its relevance as an epistemic foundation for theory construction seldom examined. The main objective of this dissertation is to offer a first systematic analysis of the nature, structure, function and epistemic reach of the cultural inheritance analogy as the conceptual foundation of the dual-inheritance theory. By insisting on its logical structure, it is argued here that it is a complex analogy, the complexity of which is often misunderstood by the criticisms levelled against the dual-inheritance theory. It is argued here that the cultural inheritance analogy is in fact composed of two constitutive analogies that conjointly justify and organize a Darwinian research program of cultural evolution.
283

Effect Of Conceptual Change Texts Accompanied With Analogies On Understanding Of Chemical Bonding Concepts

Pabuccu, Aybuke 01 July 2004 (has links) (PDF)
The purpose of this study was to explore the effects of CCTIA over TDCI for 9th grade students&rsquo / understanding of chemical bonding concepts. Also, the effect of instruction on students&rsquo / attitude toward chemistry as a school subject and the effect of gender difference on understanding of chemical bonding concepts and attitudes toward chemistry were investigated. The subjects of this study consisted of 41 ninth grade students from two classes of a chemistry course in TED Ankara High School. This study was conducted during the 2003-2004-spring semester. The classes were randomly assigned as control and experimental groups. Students in the control group were instructed by TDCI whereas students in the experimental group were instructed by CCTIA. CBCT was administered to both groups as a pre-test and post-test in order to assess their understanding of concepts related to chemical bonding. Students were also given ASTC as a school subject at the beginning and end of the study to determine their attitudes and SPST at the beginning of the study to measure their science process skills. At the end of the study, we administered interviews to the students. The hypotheses were tested by using ANCOVA and ANOVA. The results revealed that CCTIA caused a significantly better understanding of scientific conceptions related to chemical bonding concepts than the TDCI. In addition, these two modes of instruction developed the similar attitude toward science as a school subject. Also, science process skill was a strong predictor in understanding the concepts related to chemical bonding. Alternatively, no significant effect of gender difference on understanding the concepts about chemical bonding and on students&rsquo / attitudes toward chemistry as a school subject was found.
284

The Effects Of Instruction With Analogy-enhanced Model On Ninth Grade Students

Akman, Caner 01 September 2005 (has links) (PDF)
This study was conducted to investigate the effect of analogy-enhanced instruction on students&rsquo / achievement in function and attitudes toward mathematics. The study was conducted with 63 ninth grade students in one of the public high schools in Konya, Turkey during Spring 2005 semester. The experimental group received instruction with analogy-enhanced model. The control group received instruction with traditional method. The matching-only pre-test- post-test control group design was used in the study. The following measuring instruments were used to collect data: The Function Achievement Test, Mathematics Attitude Scale and open ended questions. The data of the present study were analyzed by using Multivariate Analysis of Variance (MANOVA) and paired t-test. Results of the study indicated that: (1) There was a significant mean difference between students received instruction with analogy-enhanced models and those received instruction with traditional method in terms of the function achievement, (2) there was no significant mean difference between students received instruction with analogy-enhanced models and those received instruction with traditional method in terms of attitudes toward mathematics, (3) there was a significant mean difference between gained scores of students received instruction with analogy-enhanced method and those received instruction with traditional method in terms of attitudes toward mathematics.
285

Multidimensional viscous flows at superorbital speeds

Silvester, Todd Unknown Date (has links)
A combined experimental and numerical study of multidimensional viscous flows at speeds exceeding 8 km/s is reported. Experiments were performed in the X3 superorbital expansion tube with air and nitrogen test flows at a Mach number and total enthalpy of 10 and 40 MJ/kg, respectively. Laminar skin friction, heat flux and pressure measurements were obtained at regular intervals along one wall of a rectangular duct. The spatial resolution of the transducers was chosen to capture the multidimensional flow phenomena within the duct. Quasi-steady flow periods were established along the entire length of the duct in the test times offered by the expansion tube. Direct skin friction measurements were accomplished through the use of ‘in house’ acceleration compensated transducers. The successful operation of these skin friction transducers in a high performance expansion tube was demonstrated. Furthermore, the systematic uncertainty in measured shear stress was significantly reduced with the development of a new pressure calibration technique. For the conditions tested, Reynolds analogy was shown to be valid to within experimental uncertainty. The experimental data was in excellent agreement with numerical estimates. Three-dimensional numerical simulations of the diverging duct revealed that the flowfield structure in the vicinity of the corners differs from that of an unbounded corner or a constant area duct. Real gas effects other than those present in the residual nonequilibrium levels of freestream dissociation were negligible for the conditions tested. A computational study of two waverider configurations recently tested in the X3 superorbital expansion tube was conducted to assist in the interpretation of past results. The off-design aerodynamic performance was also analyzed and showed that blunting the leading edges dramatically degraded the performance by increasing drag and decreasing lift for the conditions considered.
286

Multidimensional viscous flows at superorbital speeds

Silvester, Todd Unknown Date (has links)
A combined experimental and numerical study of multidimensional viscous flows at speeds exceeding 8 km/s is reported. Experiments were performed in the X3 superorbital expansion tube with air and nitrogen test flows at a Mach number and total enthalpy of 10 and 40 MJ/kg, respectively. Laminar skin friction, heat flux and pressure measurements were obtained at regular intervals along one wall of a rectangular duct. The spatial resolution of the transducers was chosen to capture the multidimensional flow phenomena within the duct. Quasi-steady flow periods were established along the entire length of the duct in the test times offered by the expansion tube. Direct skin friction measurements were accomplished through the use of ‘in house’ acceleration compensated transducers. The successful operation of these skin friction transducers in a high performance expansion tube was demonstrated. Furthermore, the systematic uncertainty in measured shear stress was significantly reduced with the development of a new pressure calibration technique. For the conditions tested, Reynolds analogy was shown to be valid to within experimental uncertainty. The experimental data was in excellent agreement with numerical estimates. Three-dimensional numerical simulations of the diverging duct revealed that the flowfield structure in the vicinity of the corners differs from that of an unbounded corner or a constant area duct. Real gas effects other than those present in the residual nonequilibrium levels of freestream dissociation were negligible for the conditions tested. A computational study of two waverider configurations recently tested in the X3 superorbital expansion tube was conducted to assist in the interpretation of past results. The off-design aerodynamic performance was also analyzed and showed that blunting the leading edges dramatically degraded the performance by increasing drag and decreasing lift for the conditions considered.
287

Multidimensional viscous flows at superorbital speeds

Silvester, Todd Unknown Date (has links)
A combined experimental and numerical study of multidimensional viscous flows at speeds exceeding 8 km/s is reported. Experiments were performed in the X3 superorbital expansion tube with air and nitrogen test flows at a Mach number and total enthalpy of 10 and 40 MJ/kg, respectively. Laminar skin friction, heat flux and pressure measurements were obtained at regular intervals along one wall of a rectangular duct. The spatial resolution of the transducers was chosen to capture the multidimensional flow phenomena within the duct. Quasi-steady flow periods were established along the entire length of the duct in the test times offered by the expansion tube. Direct skin friction measurements were accomplished through the use of ‘in house’ acceleration compensated transducers. The successful operation of these skin friction transducers in a high performance expansion tube was demonstrated. Furthermore, the systematic uncertainty in measured shear stress was significantly reduced with the development of a new pressure calibration technique. For the conditions tested, Reynolds analogy was shown to be valid to within experimental uncertainty. The experimental data was in excellent agreement with numerical estimates. Three-dimensional numerical simulations of the diverging duct revealed that the flowfield structure in the vicinity of the corners differs from that of an unbounded corner or a constant area duct. Real gas effects other than those present in the residual nonequilibrium levels of freestream dissociation were negligible for the conditions tested. A computational study of two waverider configurations recently tested in the X3 superorbital expansion tube was conducted to assist in the interpretation of past results. The off-design aerodynamic performance was also analyzed and showed that blunting the leading edges dramatically degraded the performance by increasing drag and decreasing lift for the conditions considered.
288

Multidimensional viscous flows at superorbital speeds

Silvester, Todd Unknown Date (has links)
A combined experimental and numerical study of multidimensional viscous flows at speeds exceeding 8 km/s is reported. Experiments were performed in the X3 superorbital expansion tube with air and nitrogen test flows at a Mach number and total enthalpy of 10 and 40 MJ/kg, respectively. Laminar skin friction, heat flux and pressure measurements were obtained at regular intervals along one wall of a rectangular duct. The spatial resolution of the transducers was chosen to capture the multidimensional flow phenomena within the duct. Quasi-steady flow periods were established along the entire length of the duct in the test times offered by the expansion tube. Direct skin friction measurements were accomplished through the use of ‘in house’ acceleration compensated transducers. The successful operation of these skin friction transducers in a high performance expansion tube was demonstrated. Furthermore, the systematic uncertainty in measured shear stress was significantly reduced with the development of a new pressure calibration technique. For the conditions tested, Reynolds analogy was shown to be valid to within experimental uncertainty. The experimental data was in excellent agreement with numerical estimates. Three-dimensional numerical simulations of the diverging duct revealed that the flowfield structure in the vicinity of the corners differs from that of an unbounded corner or a constant area duct. Real gas effects other than those present in the residual nonequilibrium levels of freestream dissociation were negligible for the conditions tested. A computational study of two waverider configurations recently tested in the X3 superorbital expansion tube was conducted to assist in the interpretation of past results. The off-design aerodynamic performance was also analyzed and showed that blunting the leading edges dramatically degraded the performance by increasing drag and decreasing lift for the conditions considered.
289

A reutilização de modelos de requisitos de sistemas por analogia : experimentação e conclusões / Systems requirements reuse by analogy: examination and conclusions

Zirbes, Sergio Felipe January 1995 (has links)
A exemplo de qualquer outra atividade que se destine a produzir um produto, a engenharia de software necessariamente passa por um fase inicial, onde necessário definir o que será produzido. A análise de requisitos é esta fase inicial, e o produto dela resultante é a especificação do sistema a ser construído. As duas atividades básicas durante a analise de requisitos são a eliciação (busca ou descoberta das características do sistema) e a modelagem. Uma especificação completa e consistente é condição indispensável para o adequado desenvolvimento de um sistema. Muitos tem sido, entretanto, os problemas enfrentados pelos analistas na execução desta tarefa. A variedade e complexidade dos requisitos, as limitações humanas e a dificuldade de comunicação entre usuários e analistas são as principais causas destas dificuldades. Ao considerarmos o ciclo de vida de um sistema de informação, verificamos que a atividade principal dos profissionais em computação é a transformação de uma determinada porção do ambiente do usuário, em um conjunto de modelos. Inicialmente, através de um modelo descritivo representamos a realidade. A partir dele derivamos um modelo das necessidades (especificação dos requisitos), transformando-o a seguir num modelo conceitual. Finalizando o ciclo de transformações, derivamos o modelo programado (software), que ira se constituir no sistema automatizado requerido. Apesar da reconhecida importância da analise dos requisitos e da conseqüente representação destes requisitos em modelos, muito pouco se havia inovado nesta área ate o final dos anos 80. Com a evolução do conceito de reutilização de software para reutilização de especificações ou reutilização de modelos de requisitos, finalmente surge não apenas um novo método, mas um novo paradigma: a reutilização sistemática (sempre que possível) de modelos integrantes de especificações de sistemas semelhantes ao que se pretende desenvolver. Muito se tem dito sobre esta nova forma de modelagem e um grande número de pesquisadores tem se dedicado a tornar mais simples e eficientes várias etapas do novo processo. Entretanto, para que a reutilização de modelos assuma seu papel como uma metodologia de use geral e de plena aceitação, resta comprovar se, de fato, ele produz software de melhor quantidade e confiabilidade, de forma mais produtiva. A pesquisa descrita neste trabalho tem por objetivo investigar um dos aspectos envolvido nesta comprovação. A experimentação viabilizou a comparação entre modelos de problemas construídos com reutilização, a partir dos modelos de problemas similares previamente construídos e postos a disposição dos analistas, e os modelos dos mesmos problemas elaborados sem nenhuma reutilização. A comparação entre os dois conjuntos de modelos permitiu concluir, nas condições propostas na pesquisa, serem os modelos construídos com reutilização mais completos e corretos do que os que foram construídos sem reutilização. A apropriação dos tempos gastos pelos analistas durante as diversas etapas da modelagem, permitiu considerações sobre o esforço necessário em cada um dos dois tipos de modelagem. 0 protocolo experimental e a estratégia definida para a pesquisa possibilitaram também que medidas pudessem ser realizadas com duas series de modelos, onde a principal diferença era o grau de similaridade entre os modelos do problema reutilizado e os modelos do problema alvo. A variação da qualidade e completude dos dois conjuntos de modelos, bem como do esforço necessário para produzi-los, evidenciou uma questão fundamental do processo: a reutilização só terá efeitos realmente produtivos se realizada apenas com aplicações integrantes de domínios específicos e bem definidos, compartilhando, em alto grau, dados e procedimentos. De acordo com as diretrizes da pesquisa, o processo de reutilização de modelos de requisitos foi investigado em duas metodologias de desenvolvimento: na metodologia estruturada a modelagem foi realizada com Diagramas de Fluxo de Dados (DFD's) e na metodologia orientada a objeto com Diagramas de Objetos. A pesquisa contou com a participação de 114 alunos/analistas, tendo sido construídos 175 conjuntos de modelos com diagramas de fluxo de dados e 23 modelos com diagramas de objeto. Sobre estas amostras foram realizadas as analises estatísticas pertinentes, buscando-se responder a um considerável número de questões existentes sobre o assunto. Os resultados finais mostram a existência de uma série de benefícios na análise de requisitos com modelagem baseada na reutilização de modelos análogos. Mas, a pesquisa em seu todo mostra, também, as restrições e cuidados necessários para que estes benefícios de fato ocorram. / System Engineering, as well as any other product oriented activity, starts by a clear definition of the product to be obtained. This initial activity is called Requirement Analysis and the resulting product consists of a system specification. The Requirement Analysis is divided in two separated phases: elicitation and modeling. An appropriate system development definition relies in a complete, and consistent system specification phase. However, many problems have been faced by system analysts in the performance of such task, as a result of requirements complexity, and diversity, human limitations, and communication gap between users and developers. If we think of a system life cycle, we'll find out that the main activity performed by software engineers consists in the generation of models corresponding to specific parts of the users environment. This modeling activity starts by a descriptive model of the portion of reality from which the requirement model is derived, resulting in the system conceptual model. The last phase of this evolving modeling activity is the software required for the system implementation. In spite of the importance of requirement analysis and modeling, very little research effort was put in these activities and none significant improvement in available methodologies were presented until the late 80s. Nevertheless, when the concepts applied in software reuse were also applied to system specification and requirements modeling, then a new paradigm was introduced, consisting in the specification of new systems based on systematic reuse of similar available system models. Research effort have been put in this new modeling technique in the aim of make it usable and reliable. However, only after this methodology is proved to produce better and reliable software in a more productive way, it would be world wide accepted by the scientific and technical community. The present work provides a critical analysis about the use of such requirement modeling technique. Experimental modeling techniques based on the reuse of similar existing models are analyzed. Systems models were developed by system analyst with similar skills, with and without reusing previously existing models. The resulting models were compared in terms of correction, consumed time in each modeling phase, effort, etc. An experimental protocol and a special strategy were defined in order to compare and to measure results obtained from the use of two different groups of models. The main difference between the two selected groups were the similarity level between the model available for reuse and the model to be developed. The diversity of resulting models in terms of quality and completeness, as well in the modeling effort, was a corroboration to the hypothesis that reuse effectiveness is related to similarity between domains, data and procedures of pre-existing models and applications being developed. In this work, the reuse of requirements models is investigated in two different methodologies: in the first one, the modeling process is based on the use of Data Flow Diagrams, as in the structured methodology; in the second methodology, based on Object Orientation, Object Diagrams are used for modeling purposes. The research was achieved with the cooperation of 114 students/analysts, resulting in 175 series of Data Flow Diagrams and 23 series of Object Diagrams. Proper statistical analysis were conducted with these samples, in order to clarify questions about requirements reuse. According to the final results, modeling techniques based on the reuse of analogous models provide an improvement in requirement analysis, without disregarding restrictions resulting from differences in domain, data and procedures.
290

The development of Islamic jurisprudence (fiqh) and reasons for juristic disagreements among schools of law

Ahmed, Shoayb 30 November 2005 (has links)
Islamic Jurisprudence comprises of the laws that govern a Muslims daily life. The Prophet Muhammad explained and practically demonstrated these laws. The jurists studied the Quran and the Prophet's life and they adopted a refined methodology which they used to extract legal rulings and verdicts. This methodology is known as the Principles of Jurisprudence. The jurists expanded on this methodology with some differences among them on the usage and the application of some aspects as acceptable forms of evidence. Eventually, the Muslim world was left with four schools of jurisprudence that are present to this day. There are differences between these schools on some issues but these differences never caused conflict, instead it provided us with a wealth of knowledge. We need to study these schools and its principles together with the objectives and intent of the Shariah and utilize this to find solutions to all new issues that arise. / Religious Studies and Arabic / M. A. (Islamic Studies)

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