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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.
101

Supporting Framework Use via Automatically Extracted Concept-Implementation Templates

Heydarnoori, Abbas January 2009 (has links)
Object-oriented application frameworks allow the reuse of both software design and code and are one of the most effective reuse technologies available today. Frameworks provide domain-specific concepts, which are generic units of functionality. Framework-based applications are constructed by writing completion code that instantiates these concepts. The instantiation of such concepts requires implementation steps in the completion code, such as subclassing framework-provided classes, implementing interfaces, and calling appropriate framework services. Unfortunately, many existing frameworks are difficult to use because of their large and complex APIs and often incomplete user documentation. To cope with this problem, application developers often use existing framework applications as a guide. While existing applications contain valuable examples of concept implementation steps, locating them in the application code is often challenging. To address this issue, this dissertation introduces the notion of concept implementation templates, which summarize the necessary concept implementation steps, and a technique named FUDA (Framework API Understanding through Dynamic Analysis) which automatically extracts such templates from runtime information collected when that concept is invoked in two or more different contexts in one or more sample applications. The experimental evaluation of FUDA with twelve realistic concepts on top of four widely-used frameworks suggests that the technique is effective in producing quality implementation templates for a given concept with high precision and recall from only two sample sample applications and execution scenarios. Moreover, it was observed in a user study with twelve subjects that the choice of templates vs. documentation had much less impact on development time than the concept complexity.
102

Untersuchung der Formstabilität verschiedener Kunststoffe zur Herstellung steriler dentaler Implantatschablonen / Study of the form stability of various plastics for the production of sterile dental implant drilling templates

Mehnert, Julika 01 October 2013 (has links)
No description available.
103

Reikalavimų specifikavimo šablonų pagrindu analizė ir programinis prototipas / Analysis of requirements specification using templates and programme prototype

Zinkevičius, Egidijus 04 March 2009 (has links)
Reikalavimų inžinerija yra bene svarbiausias etapas informacinės sistemos kūrime. Tik tikslus reikalavimų specifikavimo proceso valdymas leis sėkmingai projektuoti, realizuoti ir įdiegti informacines sistemas kompiuterizuojamose srityse. Dažnai neefektyvus reikalavimų rinkimo procesas tampa projekto nesėkmės ar programinės įrangos defekto pagrindu. Be to, aptiktų netikslumų pašalinimo kaina kyla eksponentiškai, kai jie atrandami vėlyvosiose projekto stadijose. Todėl įmonės ar asmenys, siekiantys pagerinti projekto kokybę ir produktyvumą, turėtų ypatingai atkreipti dėmesį į reikalavimų valdymo procesą. Pastebėta, jog reikalavimų specifikavimo procesas vis labiau kompiuterizuojamas, o reikalavimų valdymo įrankių bei šablonų naudojimas gerina reikalavimų specifikacijos ir būsimo produkto kokybę. Šis magistrinis darbas yra skirtas reikalavimų specifikavimo šablonų pagrindu eksperimentiniam tyrimui ir jo vertinimui. / The usage of computers takes more important place in our modern life. It was noticed that more and more enterprises use requirement management tools and specification templates to increase quality of requirement specification and projects. Very often ineffective requirements-gathering processes are the source of project failures and software defects. In addition, the cost of fixing defects rises exponentially as their discovery occurs later in the development process. However, a solid requirements process is fundamental to an effective overall process, and companies seeking increased quality and productivity should start with the requirements process. The intention of this work is to make the experimental research of requirements specification using templates and evaluate it.
104

ISSUES RELATED TO THE NUMERICAL IMPLEMENTATION OF A SPARSE METHOD FOR THE SOLUTION OF VOLUME INTEGRAL EQUATIONS AT LOW FREQUENCIES

Arcot, Kiran 01 January 2010 (has links)
Computational electromagnetic modeling involves generating system matrices by discretizing integral equations and solving the resulting system of linear equations. Many methods of solving the system of linear equations exist and one such method is the factorization of the matrix using the so called local-global solution (LOGOS) modes. Computer codes to perform the discretization of the integral equations, filling of the matrix, and the subsequent LOGOS factorization have previously been developed by others. However, these codes are limited to complex double precision arithmetic only. This thesis extends and expands the existing computer by creating a more general implementation that is able to analyze a problem not only in complex double precision but also in real double precision and both complex and real single precision. The existing code is expanded using "templates" in Fortran 90 and the resulting generic code is used test the performance of the LOGOS (both OL- and NL-LOGOS) factorization on matrices generated by discretization of the volume integral equation. As part of this effort, we demonstrate for the first time that the LOGOS factorization provides an O(N log N) complexity solution to the volume integral equation formulation of low-frequency electromagnetic problems.
105

Software Engineering Best Practices for Parallel Computing Development

patney, vikas January 2010 (has links)
In today’s computer age, the numerical simulations are replacing the traditional laboratory experiments. Researchers around the world are using advanced computer software and multiprocessor computer technology to perform experiments, and analyse these simulation results to advance in their respective endeavours. With a wide variety of tools and technologies available, it could be a tedious and time taking task for a non-computer science researcher to choose appropriate methodologies for developing simulation software The research of this thesis addresses the use of Message Passing Interface (MPI) using object-oriented programming techniques and discusses the methodologies suitable to scientific computing, also, propose a customized software engineering development model.
106

Capturing molecules with templated materials: analysis and rational design of molecularly imprinted polymers

Wei, Shuting 09 July 2007 (has links)
Advantages such as chemical, mechanical and thermal stability together with high selectivity for the templated analyte render molecularly imprinted polymers MIPs interesting alternatives to routinely applied separation materials or antibodies. Nevertheless, many factors such as the choice of functional monomer, cross-linker, and porogenic solvent, as well as the ratio between template, functional monomer, and cross-linker will affect the resulting imprinting efficiency and polymer particle size and morphology. The research described in this thesis contributes to the development of new synthetic strategies for the generation of imprinted micro- and nanospheres for 17beta-estradiol (E2) focusing on accurate control and optimization of the governing parameters for precipitation polymerization, including the polymerization temperature and the cross-linker, yielding a one-step synthetic approach with superior control on the bead diameter, shape, monodispersity and imprinting efficiency. Thus synthesized imprinting materials for E2 were successfully applied in HPLC separation, solid phase extraction and radioligand binding assays. As the optimization of imprinted materials is based on fundamental understanding of the binding site properties, the investigations is aimed at establishing a more rational basis for further tailoring imprinted materials to the desired analytical application. The relationships between the particle porosity and rebinding properties were detailed, providing useful guidelines for controlling the particle properties for the desired application including, SPE pre-concentration, HPLC separations, and biomimetic binding assays. Furthermore, analytical techniques (1H-NMR and IR, etc.) and molecular modeling were combined in this thesis to facilitate advanced understanding of the fundamental principles governing selective recognition of molecularly imprinted polymers at a molecular level. The molecular interactions involved in the templating process of molecularly imprinted polymers based on the self-assembly approach were simulated in molecular dynamic simulation model by building a modeling system include all the imprinting components with correct ratio, which has never been reported before. Molecular level interactions such as hydrogen bonding, π-π stacking interactions as well as the free energy governing complex formation of E2 with the functional monomers 4-vinylpyridine (4VP) and methacrylic acid (MAA), and the cross-linker divinylbenzene (DVB) were discussed.
107

Design of High Performance Computing Software for Genericity and Variability

Ljungberg, Malin January 2007 (has links)
Computer simulations have emerged as a cost efficient complement to laboratory experiments, as computers have become increasingly powerful. The aim of the present work is to explore the ideas of some state of the art software development practices, and ways in which these can be useful for developing high performance research codes. The introduction of these practices, and the modular designs that they give rise to, raises issues regarding a potential conflict between runtime efficiency on one hand and development efficiency on the other. Flexible software modules, based on mathematical abstractions, will provide support for convenient implementation and modification of numerical operators. Questions still remain about whether such modules will provide the efficiency which is required for high performance applications. To answer these questions, investigations were performed within two different problem domains. The first domain consisted of modular frameworks for the numerical solution of Partial Differential Equations. Such frameworks proved a suitable setting, since several of my research questions revolved around the issue of modularity. The second problem domain was that of symmetry exploiting algorithms. These algorithms are based on group theory, and make ample use of mathematical abstractions from that field. The domain of symmetry exploiting algorithms gave us opportunities to investigate difficulties in combining modularity based on high level abstractions with low level optimizations using data layout and parallelization. In conclusion, my investigation of software development practices for the area of high performance computing has proved very fruitful indeed. I have found that none of the concerns that were raised should lead us to refrain from the use of the practices that I have considered. On the contrary, in the two case studies presented here, these practices lead to designs that perform well in terms of usability as well as runtime efficiency.
108

Template synthesis and surface modification of metal oxides

Drisko, Glenna Lynn January 2010 (has links)
Agarose gel was used as a template to prepare zirconium titanium mixed oxide pellets with bimodal porosity. The materials were fully characterized to assess the effect ofZr:Ti ratio on the physical properties. It was found that the metal oxide ratio had an impact on surface acidity, the number of surface hydroxyl groups, the surface area the crystallinity and the mesopore diameter. The oxides were tested for the adsorption of vanadium ions to determine which Zr mole fraction exhibited the highest loading capacity and the fastest kinetics. A comparative study demonstrated that a hierarchical pore structure had enhanced mass transport properties over a monomodal pore structure of similar Zr:Ti composition. / Three porous zirconium titanium oxides (25 mol% Zr) were synthesized using sol-gel chemistry. One of the materials was templated from agarose gel, the second was produced without the use of a template and the third was templated from stearic acid. All three materials varied in pore architecture. Surface modification was performed post-synthetically using propionic acid (a monomer), glutaric acid (a dimer) and three molecular weights of poly(acrylic acid). Higher loading within the inorganic support was obtained for the polymers than for the smaller molecules. It was found that the pore architecture had a strong bearing on the quantity of polymer incorporated into the metal oxide framework and some effect on the rate of polymer adsorption. Thus there is great value in using templates to control pore structure. The materials were subjected to irradiation with 60Co γ-rays to determine the stability of the inorganic support and the organic functionality. / Hybrid materials were prepared by coating five distinct macroporous commercial membranes with zirconium titanium oxide using sol-gel chemistry. Calcination of these templated materials produced oxide membranes which had a suite of macropore and mesopore architectures, pore volumes and surface areas. These differences in physical properties were used to conduct a fundamental study on the relationship between the mesopore size and volume and the capacity for polymer incorporation. It was found that the polymer loading capacity was highly dependent on the pore size and pore volume. As surface area increased, loading capacity decreased, indicating that much of the increased internal surface was inaccessible to the macromolecules. Thus, mesopore diameter and pore volume must be considered when designing a mesoporous solid support. / Hierarchically porous zirconium titanium oxide and carbon zirconium titanium oxide beads with adjustable meso- and macroporosity were prepared in a one-pot, engineering-friendly process. Poly(acrylonitrile) and block copolymer Pluronic F127 were used as structure directing agents. These millimeter sized spheres were fabricated through drop-wise addition of the template-metal alkoxide solution into either water or liquid nitrogen. Carbon zirconium titanium oxide beads were produced by carbonizing the beads at 550 °C in an inert atmosphere. The (carbon) zirconium titanium oxide beads were assessed for surface accessibility and adsorption rate by monitoring the adsorption of uranyl from solution. / Porous metal oxide monoliths, specifically silica, titania, zirconia and mixed oxides containing aluminum and yttrium, were prepared in a one-pot synthesis. Macroporosity was induced using the phase separation of furfuryl alcohol. These materials have a suite of mesopore and macropore structures, the domains of which can be controlled by adjusting the synthesis conditions. These conditions were studied in detail to optimize the pore interconnectivity, the monolith stability, the pore volume and the surface area.
109

ChangeLedge : change design and planning in networked systems based on reuse of knowledge and automation / ChangeLedge: projeto e planejamento de mudanças em sistemas de rede com base no reuso de conhecimento e automação

Cordeiro, Weverton Luis da Costa January 2009 (has links)
A gerência adequada de recursos e serviços de Tecnologia da Informação (TI) se tornou imperativa para o sucesso de organizações modernas. A Biblioteca de Infraestrutura de Tecnologia da Informação (Information Technology Infrastructure Library, ITIL) representa, nesse contexto, o framework mais popular para ajudar a alcançar esse fim. Para lidar com mudanças em TI, a ITIL define o processo de gerência de mudanças (change management), cujo principal objetivo é garantir que métodos e procedimentos padronizados são utilizados para o tratamento imediato e eficiente dessas mudanças. Para alcançar esse objetivo, é fundamental reutilizar a experiência adquirida com mudanças passadas no projeto de requisições futuras. A ITIL sugere o uso de modelos de mudanças (change models) como uma forma para permitir o reuso de tal experiência em mudanças recorrentes e similares. A criação de modelos de mudanças pode ser concretizada considerando duas abordagens distintas. Em uma abordagem top-down, operadores de TI podem projetar os modelos manualmente, com base no conhecimento adquirido no passado. Em uma perspectiva alternativa, bottom-up, esses modelos poderiam ser extraídos a partir de traços de mudanças passadas obtidos com orquestradores de mudanças. Na prática, no entanto, mudanças tem sido geralmente descritas e documentadas de forma ad hoc, devido `a falta de mecanismos adequados para apoiar o projeto das mesmas. Isso impede que o conhecimento adquirido na especificação, planejamento e condução de mudanças passadas seja reutilizado em requisições futuras. Para abordar esse problema, nesta dissertação são propostos (i ) o conceito de templates de mudança como um mecanismo para formalizar, preservar, e (re)usar conhecimento na especificação de mudanças recorrentes e similares, (ii ) um algoritmo para o refinamento automatizado de planos de mudanças em workflows executáveis, (iii ) um mecanismo para extrair templates de mudanças a partir de traços de execuções passadas, e (iv) uma solução fim-a-fim, apoiada por um sistema real, para permitir o planejamento e implantação de mudanças em TI. Para provar conceito e viabilidade técnica da solução proposta, foi realizada uma implementação prototípica de um sistema de gerência de mudanças chamado ChangeLedge, o qual foi utilizado para conduzir uma série de experimentos considerando mudanças típicas em TI. Os resultados alcançados indicam a efetividade da solução e eficiência do sistema, o qual é capaz de gerar planos de mudança executáveis e corretos em um período de tempo substancialmente menor que o que seria gasto por um operador humano experiente, e de extrair templates que descrevem com acurácia mudanças passadas executadas na organização. / Proper management of Information Technology (IT) resources and services has become imperative for the success of modern organizations. The IT Infrastructure Library (ITIL) represents, in this context, the most widely accepted framework to help achieve this end. In order to deal with IT changes, ITIL defines the change management process, whose main goal is to ensure that standardized methods and procedures are used for the efficient and prompt handling of these changes. To meet this goal, it is of paramount importance reusing the experience acquired from previous changes in the design of subsequent ones. ITIL suggests the use of change models as a mean of enabling the reuse of such experience across recorrent, similar changes. The creation of change models can be done considering two distinct approaches. In a top-down approach, IT operators may manually design models based on the knowledge owned/acquired in the past. In contrast, in a bottom-up perspective, these models could be discovered from past execution traces gathered from IT provisioning tools. In practice, however, changes have been usually described and documented in an ad hoc fashion, due to the lack of proper mechanisms to both support the change design process. This hampers knowledge acquired when specifying, planning, and carrying out previous changes to be reused in subsequent requests. To address this problem, in this thesis we propose (i ) the concept of change templates as a mechanism to formalize, preserve, and (re)use knowledge in the specification of (recurrent and similar) IT changes, (ii ) an algorithm for the automated refinement of change plans into actionable workflows, (iii ) a mechanism to discover change templates from traces of past changes, and (iv) an end-to-end solution, supported by a real system, to allow planning and implementation of IT changes to be designed and executed. To prove concept and technical feasibility of the proposed solution, we have developed a prototypical implementation of a change management system called ChangeLedge and used it to carry out a set of experiments, considering typical IT changes. The results obtained indicate the effectiveness of the solution and efficiency of the system, which is able to generate accurate and actionable change plans in substantially less time than would be spent by a skilled human operator, and to extract templates that accurately describe IT change procedures previously executed in the organization.
110

Synthèse de composés β2,3-hydroxy- et aminocarboxylés par réactions domino et multicomposants métallo-catalysées / Synthesis of β2,3-hydroxy- and aminocarboxylated by metallo-catalyzed domino and multicomponents reactions

Paul, Jérôme 13 November 2017 (has links)
La mise au point de réactions multicomposants métallo-catalysées permet de contribuer au développement d’une chimie plus verte. En effet, l’association des réactions multicomposants avec la catalyse, par la limitation du nombre d'étapes réactionnelles et de l'utilisation de réactifs toxiques, permet d’augmenter l’éco-compatibilité d’un procédé.L’application de ces principes a permis la synthèse cobalto-catalysée de dérivés β2,3-hydroxy- et β2,3-aminocarboxylés, composés d’intérêt croissant en chimie médicinale, à partir d'halogénures, d’accepteur de Michael et d’aldéhydes ou d’imines.Dans un premier temps, les conditions réactionnelles ont été optimisées puis l’étendue de la réaction a été étudiée afin de démontrer son caractère général. De plus, des études stéréochimiques et mécanistiques ont été réalisées par l’utilisation d’auxiliaires ou de catalyseurs chiraux de la réaction. La valorisation des composés synthétisés a également été entreprise par l'intermédiaire de réactions de post-condensation visant en particulier la synthèse d’hétérocycles. Enfin, la réaction multicomposants développée au cours de ce travail a contribué à l'établissement de nouvelles réactivités, permettant ainsi de développer l’utilisation du cobalt en synthèse organique / The elaboration of metallo-catalyzed multicomponent reactions contributes to the development of a greener chemistry. Indeed, the association of multicomponent reactions with catalysis, through the limitation of the number of reaction steps and the use of toxic reagents, allows to increase the eco-compatibility of a process.The application of these principles has enabled the cobalt-catalyzed synthesis of β2,3-hydroxy- et β2,3-aminocarboxylated derivatives, compounds of increasing interest in medicinal chemistry, starting from halogenated derivatives, Michael acceptors and aldehydes or imines.In a first part, the reaction conditions have been optimized and the scope of the reaction has then been studied to demonstrate its generality. Moreover, stereochemical and mechanistical studies have been realized by the use of chiral auxiliaries or catalysts in the reaction. The valorization of the prepared compounds has also been undertaken in post-condensation reactions in particular for the synthesis of heterocycles. The multicomponents reaction developed during this work has finally been extended to the elaboration of new reactivities, thus contributing to spread the use of cobalt in organic chemistry

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