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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.
181

[en] AN ASPECT-ORIENTED FRAMEWORK FOR SOFTWARE AGENTS MOBILITY / [pt] UM FRAMEWORK ORIENTADO A ASPECTOS PARA MOBILIDADE DE AGENTES DE SOFTWARE

CIDIANE ARACATY LOBATO 29 March 2006 (has links)
[pt] Engenheiros de sistemas multi-agentes (SMAs) móveis devem lidar com o projeto e a implementação de mobilidade de código, além do projeto e implementação de funcionalidades básicas e outros requisitos. À medida que a complexidade dos SMAs aumenta, questões referentes à mobilidade não podem ser modularizadas somente a partir da utilização de abstrações e mecanismos orientados a objetos (OO). Além disso, vários programadores freqüentemente evidenciam a presença de problemas de entrelaçamento e espalhamento em suas linhas de código referentes à mobilidade. Apesar de tais problemas, os desenvolvedores de SMAs têm se apoiado vastamente na utilização de interfaces de programação de aplicações (APIs) OO das plataformas de mobilidade e na linguagem de programação Java. O resultado é a produção de SMAs que são difíceis de entender, manter e reutilizar. Este trabalho apresenta três contribuições principais. Primeiramente, é realizada uma análise das soluções existentes para separação dos interesses de mobilidade. Além disso, são propostos a arquitetura de software ArchM e o framework AspectM, ambos baseados em aspectos, visando: (i) uma clara separação dos interesses de mobilidade em relação às funcionalidades básicas e outros requisitos, (ii) uma introdução transparente do código de mobilidade em agentes estacionários, e (iii) uma integração flexível dos SMAs com plataformas de mobilidade existentes. O desenvolvimento de software orientado a aspectos é um novo paradigma com abstrações e mecanismos de composição que possibilitam o aumento do grau de reusabilidade e manutenibilidade dos sistemas. Os benefícios de ArchM e AspectM são ilustrados através de dois estudos de caso e com o uso de duas plataformas de mobilidade. / [en] Software engineers of multi-agent systems (MASs) are concerned with the design and implementation of the mobility issues in addition to the agents` basic functionalities and other agent-related concerns. As the agents` complexity increases, mobility issues cannot be modularized based only on object-oriented (OO) abstractions and mechanisms. Besides, some programmers frequently evidence the presence of mobility tangling and scattering problems on their systems. Despite these problems, MAS developers have mostly relied on application programming interfaces (APIs) OO from mobility platforms and on the use of the Java programming language. The result is the production of MASs that are difficult to understand, maintain, and reuse. This work presents three main contributions. Firstly, an analysis of existent solutions for modularization of mobility issues. Besides, the proposal of the ArchM software architecture and the AspectM framework, both based on aspects, which support: (i) improved modularization of the mobility issues, that is, a clean separation between the mobility-specific concerns and the other agent concerns, (ii) a seamless introduction of code mobility into stationary agents, and (iii) a flexible integration with multiple mobility platforms. The aspect- oriented software development (AOSD) is a new paradigm with abstractions and composition mechanisms that support an improvement of reuse and maintainability of systems. The benefits of the AspectM framework are illustrated through two case studies and through use of two mobility platforms.
182

Design and implementation of an end-user programming software system to create and deploy cross-platform mobile mashups

Kaltofen, Sandra January 2010 (has links)
No description available.
183

Crystalline Metal-Organic Frameworks Based on Conformationally Flexible Phosphonic Acids

Gagnon, Kevin James 16 December 2013 (has links)
The goal of the work described in this dissertation was to investigate the structure of metal phosphonate frameworks which were composed of conforma-tionally flexible ligands. This goal was achieved through investigating new syn-thetic techniques, systematically changing structural aspects (i.e. chain length), and conducting in situ X-ray diffraction experiments under non-ambient condi-tions. First, the use of ionic liquids in the synthesis of metal phosphonates was in-vestigated. Reaction systems which had previously been studied in purely aqueous synthetic media were reinvestigated with the addition of a hydrophobic ionic liq-uid to the reaction. Second, the structural diversity of zinc alkylbisphosphonates was investigated through systematically varying the chain length and reaction conditions. Last, the structural changes associated with externally applied stimuli (namely temperature and pressure) on conformationally flexible metal phospho-nates were investigated. Elevated temperature was used to investigate the structur-al changes of a 1-D cobalt chain compound through three stages of dehydration and also applied pressures of up to 10 GPa were used to probe the structural resili-ence of two zinc alkylbisphosphonate materials under. The iminobis(methylphosphonic acid) type ligands are a good example of a small, simple, conformationally flexible ligand. There are three distinct different structural types, utilizing this ligand with cobalt metal, described in the literature, all of which contain bound or solvated water molecules. The addition of a hydrophobic ionic liquid to an aqueous synthesis medium resulted in new anhydrous compounds with unique structural features. Systematic investigations of zinc alkylbisphosphonate materials, construct-ed with three to six carbon linker ligands, resulted in four new families of com-pounds. Each of these families has unique structural features which may prove in-teresting in future applications developments. Importantly, it is shown that wheth-er the chain length is odd or even plays a role in structural type although it is not necessarily a requirement for a given structural type; furthermore, chain length itself is not strictly determinative of structural type. Dehydration in a cobalt phosphonate was followed via in situ single crystal X-ray diffraction. The compound goes through a two-stage dehydration mecha-nism in which the compound changes from a 1-D chain to a 2-D sheet. This pro-cess is reversible and shows unique switchable magnetic properties. The high pressure studies of an alkyl chain built zinc metal phosphonate showed that the chains provide a spring-like cushion to stabilize the compression of the system allowing for large distortions in the metal coordination environment, without destruction of the material. This intriguing observation raises questions as to whether or not these types of materials may play a role as a new class of piezo-functional solid-state materials.
184

The quality of environmental management frameworks in South Africa / Marius Marais

Marais, Marius January 2010 (has links)
Environmental assessments and authorisations surrounding project level developments are often made in isolation, without consideration of the regional or strategic context within which individual developments are done. This research investigates the quality of Environmental Management Frameworks (EMF) as strategic environmental instrument. EMF is a unique South African instrument that was first conceptualised in 1989, enacted in 2006 and updated in 2010. EMFs were developed to map environmental sensitivity to aid the screening out of undesired developments in sensitive environments and to minimise unnecessary project level assessments in preferred development areas. EMFs form an important link between environmental assessment (EA) processes and planning strategies such as Spatial Development Frameworks (SDFs) and Integrated Development Plans (IDPs), due to their spatial output of environmental sensitivity maps and their ability to feed strategic assessment processes required by SDFs. They have a legal mandate which ensures their assimilation and use. This research uses a multiple case study approach to review seven EMF documents for their quality. The quality aspects identified are the process, methodology and documentation components, using the printed EMF documentation as primary information source. Quality review criteria were subsequently developed to investigate these inputs, using the legal mandate of EMF as basis. Each case was rated for compliance with the quality criteria using a six–level rating schedule. Further analyses were made by comparing the performance of cases against one another. Public participation emerged as the weakest component of EMF practice, while aspects of sensitivity analysis also performed weaker than other aspects. More focus is required on aligning scales and resolutions of map inputs, mapping methods and general integration of spatial data, especially those of adjoining districts. The need to substantiate a rationale for buffer determination also requires further refinement. The practice of conducting EMF is well established and it can be valuable in sustainable development planning and decisionmaking. Recommendations to enhance the sustainability outcomes and hence effectiveness of this instrument are made, as well as future research objectives for increasing its utility. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.
185

The quality of environmental management frameworks in South Africa / Marius Marais

Marais, Marius January 2010 (has links)
Environmental assessments and authorisations surrounding project level developments are often made in isolation, without consideration of the regional or strategic context within which individual developments are done. This research investigates the quality of Environmental Management Frameworks (EMF) as strategic environmental instrument. EMF is a unique South African instrument that was first conceptualised in 1989, enacted in 2006 and updated in 2010. EMFs were developed to map environmental sensitivity to aid the screening out of undesired developments in sensitive environments and to minimise unnecessary project level assessments in preferred development areas. EMFs form an important link between environmental assessment (EA) processes and planning strategies such as Spatial Development Frameworks (SDFs) and Integrated Development Plans (IDPs), due to their spatial output of environmental sensitivity maps and their ability to feed strategic assessment processes required by SDFs. They have a legal mandate which ensures their assimilation and use. This research uses a multiple case study approach to review seven EMF documents for their quality. The quality aspects identified are the process, methodology and documentation components, using the printed EMF documentation as primary information source. Quality review criteria were subsequently developed to investigate these inputs, using the legal mandate of EMF as basis. Each case was rated for compliance with the quality criteria using a six–level rating schedule. Further analyses were made by comparing the performance of cases against one another. Public participation emerged as the weakest component of EMF practice, while aspects of sensitivity analysis also performed weaker than other aspects. More focus is required on aligning scales and resolutions of map inputs, mapping methods and general integration of spatial data, especially those of adjoining districts. The need to substantiate a rationale for buffer determination also requires further refinement. The practice of conducting EMF is well established and it can be valuable in sustainable development planning and decisionmaking. Recommendations to enhance the sustainability outcomes and hence effectiveness of this instrument are made, as well as future research objectives for increasing its utility. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.
186

Polímeros de coordenação à base de cobalto(II) e N,N'-bis(4-piridil)-1,4,5,8-naftaleno diimida como ligante e suas propriedade estruturais, espectroscópicas e fotoelétricas / Coordination polymers based on cobalt(II) and N,N\'-bis(4-pyridyl)-1,4,5,8-naphthalene diimide as ligand and their structural, spectroscopic and electronic properties

Evandro Castaldelli 05 February 2016 (has links)
Polímeros de coordenação têm atraído a atenção de pesquisadores na última década por conta de sua incrível versatilidade e virtualmente infinito número de possibilidades de combinação de ligantes orgânicos e centros metálicos. Estes compostos normalmente herdam as características magnéticas, eletrônicas e espectroscópicas de seus componentes base. Entretanto, apesar do crescente número de trabalhos na área, ainda são raros os polímeros de coordenação que apresentem condutividade elétrica. Para este fim, utilizou-se a N,N\'-bis(4-piridil)-1,4,5,8-naftaleno diimida, ou NDI-py, que pertence a uma classe de compostos rígidos, planares, quimicamente e termicamente estáveis e que já foram extensamente estudados por suas propriedades fotoeletroquímicas e semicondução do tipo n. O primeiro polímero de coordenação sintetizado, MOF-CoNDI-py-1, indicou ser um polímero linear, de estrutura 1D. O segundo, MOF-CoNDI-py-2, que conta com ácido tereftálico como ligante suporte, é um sólido cristalino com cela unitária monoclínica pertencente ao grupo espacial C2/c, determinado por difração de raios-X de monocristal. A rede apresenta um arranjo trinuclear de íons Co(II) alto spin com coordenados em uma geometria de octaedro distorcido, enquanto os ligantes NDI-py se encontram em um arranjo paralelo na estrutura, em distâncias apropriadas para transferência eletrônica. Com o auxílio de cálculo teóricos a nível de DFT, foi realizado um estudo aprofundado dos espectros eletrônicos e vibracionais, com atribuição das transições observadas, tanto para o MOF-CoNDI-py-2 quanto para o ligante NDI-py livre. A rede de coordenação absorve em toda a região do espectro eletrônico analisada, de 200 nm a 2500 nm, além de apresentar luminescência com característica do ligante. Dispositivos eletrônicos fabricados com um cristal do MOF-CoNDI-py-2 revelaram condutividades da ordem de 7,9 10-3 S cm -1, a maior já observada para um MOF. Além de elevada, a condutividade elétrica dos cristais demonstrou-se altamente anisotrópica, sendo significativamente menos condutor em algumas direções. Os perfis de corrente versus voltagem foram analisados em termos de mecanismos de condutividade, sendo melhores descritos por um mecanismo limitado pelo eletrodo to tipo Space-Charge Limited Current, concordando com a proposta de condutividade através dos planos de NDI-py na rede. A condutividade dos cristais também é fortemente dependente de luz, apresentando fotocondução quando irradiado por um laser vermelho, de 632 nm, enquanto apresenta um comportamento fotorresistivo frente a uma fonte de luz branca. Estes resultados, combinados, trazem um MOF em uma estrutura incomum e com elevada condutividade elétrica, modulada por luz, em medidas diretas de corrente. Não existem exemplos conhecidos de MOFs na literatura com estas características. / Coordination polymers have been a major topic in materials science during the past decade, thanks to their versatility and virtually infinite possible combinations between metal centers and organic ligands. These coordination polymers usually inherit the properties of their components, such as magnetic, spectroscopic and electronic characteristics. However, despite the increasing number of research papers in this topic, it is still hard to find coordination polymers featuring electronic conductivity. To achieve that, we used a naphthalene diimide derivative, N,N\'-bis(4-pyridyl)-1,4,5,8- naphthalene diimide or NDI-py, which belongs to a class of rigid, planar, thermally and chemically stable compounds, extensively studied due to their photoelectrochemical properties and their n-type semiconductivity. The first coordination polymer synthesised, MOF-CoNDI-py-1, was an amorphous linear polymer, with a 1D structure. Based on these observations, MOF-CoNDI-py-2 was synthesised by using terephthalic acid as a supporting ligand, and it is a crystalline solid which its monoclinic unit cell belongs to a C2/c space group, as determined by single crystal X-ray diffraction. This network features a trinuclear high-spin Co(II) unit, and each metal ion sits on a distorted octahedra coordination geometry, while the NDI-py ligands sit in a parallel arrangement, with distances suitable for electronic transfers. A detailed study of their vibrational and electronic spectra, supported by DFT calculations, was performed, as well as a full description and assignment of the observed bands. MOF-CoNDI-py-2 absorbs in the whole studied spectral region, from 200 nm to 2500 nm, while it also features a ligand-centered emission spectrum. Electronic devices built around its crystals revealed electric conductivities of 7.9 10 -3 S cm -1, which is, to the best of our knowledge, the highest for a MOF to this date. This conductivity is also highly anisotropic, being significantly less conductive in certain directions. The current versus voltage profiles were analysed in terms of known conduction mechanisms, with best fits when using an electrode-limited Space-Charge Limited Current mechanism, in agreement with the proposition that this conductivity happens through the NDI-py stacking planes. Additionally, this mechanism is influenced by an external light source, being a photoconductor with a red laser, 632 nm, and a photoresistor with a white light. Combined, these results bring a light-modulated, highly conductive MOF material with an unusual structure. As far as we know, there are no similar MOFs in the literature, which makes MOF-CoNDI-py-2 one of a kind.
187

GENIAC – Konfigurieren komplexer Produktsimulationen mit Hilfe von natürlichen Benutzeroberflächen

Wegner, Michael, Freitag, Georg, Wacker, Markus 25 September 2017 (has links) (PDF)
Mit der zunehmenden Bedeutung von virtuellen Prototypen in den frühen Phasen der Produktentwicklung wachsen ebenso die an die verwendeten Softwarelösungen gestellten Anforderungen. Sollen unterschiedliche Faktoren wie Funktionalität, Design oder auch Ergonomie getestet werden, so muss die verwendete Software Module bereitstellen, welche die Erstellung von ganzheitlichen Produktmodellen ermöglichen. Zu den benötigten Modulen zählen zum Beispiel Simulation, Grafik, Eingabeschnittstellen oder Sound. Mit der steigenden Komplexität der zu erstellenden Prototypen wächst jedoch auch der Aufwand für die Entwickler und Anwender, sich in diese einzuarbeiten, diese zu konfigurieren und zu verwalten. An dieser Stelle setzt das Forschungsprojekt GENIAC an. Sein Ziel ist es, die Konfiguration von hochkomplexen Software-Frameworks mit Hilfe natürlicher Benutzeroberflächen zu vereinfachen. Hierzu werden die zu untersuchenden Konfigurationen als Netzwerke auf großflächigen Multi-Touch Bildschirmen dargestellt und mittels natürlicher Gestensteuerung bearbeitet.
188

Using external factors to improve gas adsorption in nanoporous materials : control of humidity and mechanical pressure / Utilisation de paramètres externes pour améliorer l'adsorption de gaz dans les matériaux nanoporeux : contrôle de l'humidité et de la pression mécanique

Chanut, Nicolas 01 December 2016 (has links)
L'augmentation du niveau de CO2 atmosphérique est un sujet de préoccupation publique notoire. Afin d'atténuer son impact sur l'environnement, il est urgent de réduire les émissions de CO2 d’origines anthropiques. Une méthode considérée comme viable est la capture de CO2 par des procédés d’adsorption en utilisant une classe émergente de matériaux, les Metal-Organic Frameworks (MOFs). A ce jour, l’évaluation des MOFs s’est principalement axée sur leurs performances de séparation (capacité, sélectivité et régénération). Cependant, des facteurs externes peuvent influer sur les performances globales des procédés. L’objectif de cette thèse est d’évaluer trois d’entre eux : la présence de vapeur d’eau dans les effluents gazeux, l’effet de la mise en forme des matériaux et l’effet d’une pression mécanique externe sur les performances d’adsorption de gaz. Il est montré que ces facteurs externes peuvent être utilisés pour améliorer les performances des procédés dans des conditions spécifiques. / The increase in atmospheric CO2 level is a notorious matter of public concern. To mitigate its impact on the environment, it is urgent to reduce emissions of anthropogenic CO2. A method considered by many as a viable option is CO2 capture by adsorption using an emerging class of materials, the Metal-Organic Frameworks (MOFs). To date, evaluation of MOFs has been mainly focused on the separation performance of the material looking at the capacity, selectivity and regeneration capability. However external factors can influence the overall performances of processes turning to industrial applications. The purpose of this thesis was to evaluate three of them: the presence of water vapor in post-combustion flue gases, the effect of shaping powders into pellets form and the effect of an external mechanical pressure on gas adsorption performance. Unexpectedly, it is shown that these external factors could be used to improve process performances under specific conditions.
189

Conception et fonctionnalisation de MOFs pour le greffage et l'encapsulation de complexe organométallique / Development of MOFs as supports or host for organometallic complexes

Lescouet, Tristan 14 December 2012 (has links)
Les Metal-Organic Frameworks résultent de l’organisation de clusters métalliques et demolécules organiques chélatantes qui forment un réseau cristallin poreux. Leur découverte apermis des avancées majeures dans le domaine du stockage et de la séparation des gaz.Malheureusement la faible stabilité et l’acidité modérée de ces matériaux ne les rendent quepeu compétitifs par rapport aux zéolites dans le domaine du raffinage ou de la dépollution. Ils’agit d’explorer, avec ces matériaux, de nouvelles applications catalytiques en tirant partie deleur principale qualité : leur modularité. En effet le large choix de métaux, de ligands, ainsique la post fonctionnalisation de ces derniers permet la synthèse contrôlée de matériauxpossédant des propriétés de flexibilité, de confinement ainsi qu’un environnement chimiquesimilaire à celui des sites actifs des enzymes. Ce travail s’inspire du procédé catalytique desenzymes pour obtenir des MOFs hautement sélectifs en conditions douces. Nous décrivons ledéveloppement de méthodes pour encapsuler des catalyseurs organométalliques dans despores calibrés afin de modifier la sélectivité d’une réaction d’oxydation et stabiliser lecatalyseur. Quatre MOFs supportant des groupes amino ont été synthétisés afin de permettreleur post fonctionnalisation. Les propriétés de flexibilité ainsi que la distribution des sitespotentiellement actifs du MOF MIL-53 ont également été contrôlés grâce à lafonctionnalisation partielle de la structure. Enfin ces amino MOFs furent post fonctionnalisésen isocyanate en deux étapes afin d’améliorer la réactivité de la structure et de permettre legreffage de diverses amines. Ces outils pourraient permettre à court terme la conception deMOFs dont les pores ont un environnement semblable aux metalloenzymes. / MOFs are generated from the association of metallic clusters connected by organic linkers toform crystalline porous materials. Their discovery was a breakthrough in the domain ofseparation and gas storage. Unfortunately, MOFs have a low stability and moderate acidityand cannot compete with zeolites for use in industrial catalysis. To design a viable MOFcatalyst, we can take advantage of its almost infinite possibility of customisation. Indeed, alarge choice of metal, linkers or post synthetic modifications allow the creation ofenvironments similar to the active sites of enzymes and can lead to the synthesis of solidswith analogue flexibility or “molecular recognition” properties. This work takes inspirationfrom enzymes to mimic their ability to catalyse reactions with high chemio-, region- andenantio-selectivity in mild conditions. We developed a method for the encapsulation oforganometallic complexes in the large pore of MOF MIL-101. The selectivity of an oxidationreaction was modified and the catalyst was stabilised within the MOF. In addition, four aminofunctionalized MOFs were synthesized as starting materials for post functionalization. Theirflexibility and the active site distribution were controlled by the use of a “mixed linker”strategy: functionalized linkers were diluted with unfunctionalized ones during the synthesis.Lastly, these amino-MOFs were post-functionalized in two steps in isocyanate in order toameliorate the structure reactivity and allow for the grafting of a large range of amines. Thiswork brings the tools for the synthesis of potential “artificial enzymes”.
190

Um processo para construção e instanciação de frameworks baseados em uma linguagem de padrões para um domínio específico. / A process for construction and instantiation of frameworks based on a domain-specific pattern language.

Rosana Teresinha Vaccare Braga 14 February 2003 (has links)
Padrões, linguagens de padrões e frameworks são formas de reuso de software. A complexidade de frameworks, causada pela dificuldade tanto em construí-los quanto em utilizá-los, é um dos inibidores do uso dessa tecnologia. Um processo para facilitar a construção e instanciação de frameworks é apresentado. Uma linguagem de padrões é utilizada para apoiar todo o processo, desde a identificação da funcionalidade do framework, seu projeto, implementação, validação, até sua instanciação para sistemas específicos do domínio. O framework obtido é do tipo caixa-branca e sua instanciação é feita especializando-se suas classes para sistemas específicos. O processo inclui, também, a construção de uma ferramenta para automatizar a instanciação do framework, por meio da qual é possível obter um sistema específico fornecendo apenas informações sobre os padrões da linguagem utilizados na sua modelagem. O processo é ilustrado com a Linguagem de Padrões para Gestão de Recursos de Negócios (GRN), que serviu de base para construção do framework GREN. Apresenta-se também o GREN-Wizard, uma ferramenta para instanciação automática do GREN para sistemas no domínio da GRN. A avaliação do processo é feita por meio de alguns experimentos e vários relatos de uso dos diversos sub-processos que compõem o processo geral, usando o GREN, a GRN e o GREN-Wizard. / Patterns, pattern languages, and frameworks are ways of enhancing software reuse. The complexity of software frameworks, caused both by the difficulty to build and to use them, is one of the inhibitors of this technology. A process to ease the construction and instantiation of frameworks is presented, in which a pattern language is used to support the whole process, starting from the identification of the framework functionality, its design, implementation, validation, and its instantiation to domain-specific systems. The framework that results from applying the proposed process is white-box and its instantiation is done by specializing its abstract classes according to a specific system. The process includes the construction of a tool to automate the framework instantiation, through which it is possible to obtain a specific system only by supplying information about the language patterns used to model it. The proposed process is illustrated with the Pattern Language for Business Resource Management (GRN), which was used as the basis for the GREN framework construction. The GREN-Wizard is also presented, which is a tool to automatically instantiate the GREN framework to specific applications in the GRN domain. The proposed process is evaluated by a few experiments and several uses of the sub-processes that compose the general process, using GRN, GREN and the GREN-Wizard.

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