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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.
221

Electrochemical and Photocatalytic Oxidation of Hydrocarbons

Rismanchian, Azadeh January 2014 (has links)
No description available.
222

Mass Transport Enhancement in Copper Electrodeposition due to Gas Co-Evolution

Gonzalez-Pena, Omar Israel 03 September 2015 (has links)
No description available.
223

Det inre dramat på den yttre scenen. : En studie om Dramapedagogik och Neurolingvistisk Programmering i kombination, med avsikt att bryta begränsande mönster.

Nilsson, Annacarin January 2016 (has links)
This paper is a qualitative, theory-based study with a phenomenological, hermeneutic approach and a didactic perspective. The aim of this study is to examine three educators experience of using both Drama in education (DP) and Neurolinguistic programming (NLP) in conjunction with each other, with the aim of changing limiting patterns in individuals and groups. The study examines the following research questions: 1. How does an educator describe their work, using the combination of DP and NLP, with the aim to change limiting patterns? 2. What similarities as well as differences do educators experience between the two methodologies DP and NLP? 3. Why did the educator choose this particular combination? As background there's a brief description of education from a historic point of view and the concept of DP and NLP are explained together with examples of comprehensive research in the field. Following this: learning as theory is presented from the perspective of neuroscience, DP and NLP. Finally the concept of "limiting" patterns is described in detail.Three educators, working with both methods in conjunction, were interviewed and these interviews were compiled, compared and analysed relative to the research questions and theory derived from neuroscience and brain research.The result showes that the educators who were interviewed experienced numerous benefits from using both the DP and NLP methods in conjunction with each other - thus achieving more effective results in changing limiting patterns in people's attitudes, behaviour and outlook. Whilst both methods have similarities and differences, it's noticeable that they bring very different elements to the process. DP is seen as a collective, open and interactive approach that, together with its creative educational aspect, is contributing with a dramatic frame for exploration and visualisation of a particular subject's underlying and dominant patterns. NLP – also frequently based on a dramatic frame - is focused on how these internal patterns are distributed neurologically throughout our senses. The educators believe that DP and NLP used in conjunction creates an effective collaborative formula for change of patterns. Furthermore, NLP offers insights on how the educational approach can be effectively deepened and reinforced. Finally, the study shows that the combination works equally well in both group and individual processes. / Denna studie är en kvalitativ teorinära studie med en fenomenologisk, hermeneutisk ansats och ett didaktiskt perspektiv. Dess syfte är att undersöka tre pedagogers upplevelse av Dramapedagogik (DP) och Neurolingvistisk Programmering (NLP) i kombination, med avsikt att bryta begränsande mönster. Undersökningsfrågorna är: 1. Hur beskriver en pedagog sitt arbete att bryta begränsande mönster med kombinationen DP och NLP? 2. Vad upplever pedagogerna att det finns för likheter och skillnader mellan DP och NLP? 3. Varför har pedagogen valt denna kombination? I bakgrunden redogörs kortfattat för pedagogik ur ett historiskt perspektiv, begreppet DP och NLP beskrivs samt övergripande forskning inom områdena. Därefter redogörs för lärande inom DP, NLP samt ur ett neurovetenskapligt perspektiv. Slutligen redogörs för begreppet ”begränsande mönster”. Intervjuer av tre pedagoger som arbetar med båda metoderna gjordes, sammanställdes och analyserades efter undersökningsfrågorna och teori hämtad från neurovetenskap och hjärnforskning. Resultatet visar att de intervjuade pedagogerna upplever att det finns många fördelar med att kombinera DP och NLP i syfte att bryta begränsande mönster. De har både likheter och skillnader men framför allt tillför de helt olika saker. DP ses som en kollektiv, öppen och interaktiv metod som med sin gestaltande pedagogik tillför former för utforskande och synliggörande av underliggande och styrande mönster. NLP som också många gånger utgår från gestaltande former, är mer fokuserad på hur dessa interna mönster är ordnade neurologiskt via våra sinnen. Pedagogerna anser att DP och NLP är en effektiv kombination i ett förändringsarbete. Vidare kan NLP erbjuda insikter om hur det pedagogiska förhållningssättet kan förstärkas. Slutligen visar studien att kombinationen fungerar väl på såväl grupper som på individuella processer.
224

Novel phosphorus containing poly(arylene ethers) as flame retardant additives and as reactant in organic synthesis

Satpathi, Hirak 13 August 2015 (has links) (PDF)
Due to their outstanding properties, poly(arylene ethers) are useful as toughness modifiers in epoxy resins (EP). Furthermore, these polymers show rather low intrinsic fire risks. According to recent research it has been incorporated that poly(arylene ether phosphine oxides) [PAEPO’s] can further improve the fire behavior. Increasing phosphorous content of the PAEPO can influence the fire behavior too. Fire retardants containing phosphorus – regardless of whether an additive or reactive approach is used – show different mechanisms in the condensed and gas phase. In the present study PSU Control (BPA based polysulfone) with four different PAEPO’s and their corresponding blends with an EP were investigated. All poly(arylene ether phosphine oxides) were synthesized by nucleophilic aromatic polycondensation. The polymers obtained covered a wide range of weight average molar masses (6,000 – 150,000 g/mol) as determined by size exclusion chromatography with multi-angle light scattering detection (MALLS). FTIR, NMR spectroscopy and MALDI-TOF revealed formation of the desired polymer structure of the linear poly(arylene ethers). All polymers were easily soluble in common organic solvents, thus enabling processing from solution.The pyrolysis and the fire retardancy mechanisms of the polymers and blends with epoxy resin (EP) were tackled by means of a comprehensive thermal analysis (thermogravimetry (TG), TG-evolved gas analysis) and fire tests [PCFC, limiting oxygen index (LOI), UL-94, cone calorimeter]. The Mitsunobu reaction of Dimethyl-5-hydroxyisophthalate and a long chain semifluorinated alcohol requires triphenyl phosphine as a reactant. Identical, in some case higher yield was obtained in the usual conditions, with triphenyl phosphine and with trivalent phosphorus containing polymers, which was prepared in solvent free bulk (melt) polymerization technique from trivalent phosphorus monomer and a silylated diphenol in presence of CsF. Purification and the recovery of the final product which is always a big challenge in case of Mitsunobu reaction, was far more easier using polymer compared to triphenyl phosphine. During polymerization there was a possibility to have polymer having repeating unit containing both trivalent phosphorus and phosphine oxide. The trivalent phosphorus content of the polymer can be varied using different molar concentration of CsF.
225

Machine learning via dynamical processes on complex networks / Aprendizado de máquina via processos dinâmicos em redes complexas

Cupertino, Thiago Henrique 20 December 2013 (has links)
Extracting useful knowledge from data sets is a key concept in modern information systems. Consequently, the need of efficient techniques to extract the desired knowledge has been growing over time. Machine learning is a research field dedicated to the development of techniques capable of enabling a machine to \"learn\" from data. Many techniques have been proposed so far, but there are still issues to be unveiled specially in interdisciplinary research. In this thesis, we explore the advantages of network data representation to develop machine learning techniques based on dynamical processes on networks. The network representation unifies the structure, dynamics and functions of the system it represents, and thus is capable of capturing the spatial, topological and functional relations of the data sets under analysis. We develop network-based techniques for the three machine learning paradigms: supervised, semi-supervised and unsupervised. The random walk dynamical process is used to characterize the access of unlabeled data to data classes, configuring a new heuristic we call ease of access in the supervised paradigm. We also propose a classification technique which combines the high-level view of the data, via network topological characterization, and the low-level relations, via similarity measures, in a general framework. Still in the supervised setting, the modularity and Katz centrality network measures are applied to classify multiple observation sets, and an evolving network construction method is applied to the dimensionality reduction problem. The semi-supervised paradigm is covered by extending the ease of access heuristic to the cases in which just a few labeled data samples and many unlabeled samples are available. A semi-supervised technique based on interacting forces is also proposed, for which we provide parameter heuristics and stability analysis via a Lyapunov function. Finally, an unsupervised network-based technique uses the concepts of pinning control and consensus time from dynamical processes to derive a similarity measure used to cluster data. The data is represented by a connected and sparse network in which nodes are dynamical elements. Simulations on benchmark data sets and comparisons to well-known machine learning techniques are provided for all proposed techniques. Advantages of network data representation and dynamical processes for machine learning are highlighted in all cases / A extração de conhecimento útil a partir de conjuntos de dados é um conceito chave em sistemas de informação modernos. Por conseguinte, a necessidade de técnicas eficientes para extrair o conhecimento desejado vem crescendo ao longo do tempo. Aprendizado de máquina é uma área de pesquisa dedicada ao desenvolvimento de técnicas capazes de permitir que uma máquina \"aprenda\" a partir de conjuntos de dados. Muitas técnicas já foram propostas, mas ainda há questões a serem reveladas especialmente em pesquisas interdisciplinares. Nesta tese, exploramos as vantagens da representação de dados em rede para desenvolver técnicas de aprendizado de máquina baseadas em processos dinâmicos em redes. A representação em rede unifica a estrutura, a dinâmica e as funções do sistema representado e, portanto, é capaz de capturar as relações espaciais, topológicas e funcionais dos conjuntos de dados sob análise. Desenvolvemos técnicas baseadas em rede para os três paradigmas de aprendizado de máquina: supervisionado, semissupervisionado e não supervisionado. O processo dinâmico de passeio aleatório é utilizado para caracterizar o acesso de dados não rotulados às classes de dados configurando uma nova heurística no paradigma supervisionado, a qual chamamos de facilidade de acesso. Também propomos uma técnica de classificação de dados que combina a visão de alto nível dos dados, por meio da caracterização topológica de rede, com relações de baixo nível, por meio de medidas de similaridade, em uma estrutura geral. Ainda no aprendizado supervisionado, as medidas de rede modularidade e centralidade Katz são aplicadas para classificar conjuntos de múltiplas observações, e um método de construção evolutiva de rede é aplicado ao problema de redução de dimensionalidade. O paradigma semissupervisionado é abordado por meio da extensão da heurística de facilidade de acesso para os casos em que apenas algumas amostras de dados rotuladas e muitas amostras não rotuladas estão disponíveis. É também proposta uma técnica semissupervisionada baseada em forças de interação, para a qual fornecemos heurísticas para selecionar parâmetros e uma análise de estabilidade mediante uma função de Lyapunov. Finalmente, uma técnica não supervisionada baseada em rede utiliza os conceitos de controle pontual e tempo de consenso de processos dinâmicos para derivar uma medida de similaridade usada para agrupar dados. Os dados são representados por uma rede conectada e esparsa na qual os vértices são elementos dinâmicos. Simulações com dados de referência e comparações com técnicas de aprendizado de máquina conhecidas são fornecidos para todas as técnicas propostas. As vantagens da representação de dados em rede e de processos dinâmicos para o aprendizado de máquina são evidenciadas em todos os casos
226

La protection des "parties faibles" dans le règlement "Rome I" / The protection of "weak parties" in the "Rome I" regulation

Boukaram, Sahar 07 December 2015 (has links)
Le « marché intérieur » est générateur de contrats internationaux intra et extra-européens. La multiplication de ces contrats nécessite un marché intérieur « espace de liberté, de sécurité et de justice ». Le règlement « Rome I », instrument de droit international privé communautaire, assure la liberté contractuelle et la sécurité juridique par l’élaboration de règles générales de conflit de lois. La volonté d’assurer la justice contractuelle a donné lieu pour sa part à l’élaboration de règles spéciales de conflit de lois, qui visent à protéger les contractants en situation de faiblesse sociale ou économique face à leur cocontractant partie forte. Le règlement « Rome I » a ainsi consacré des règles spéciales de conflit de lois protectrices des intérêts des travailleurs, des consommateurs, des passagers voyageant au départ ou à destination de leur pays de résidence, des preneurs d’assurance de risques de masse communautaires, ainsi que des distributeurs et des franchisés. Toutefois, le succès du marché intérieur impose de parvenir à établir un équilibre entre la justice contractuelle, la liberté contractuelle et la sécurité juridique, même dans le cadre des règles spéciales protectrices de conflit de lois. Cet équilibre ne peut être atteint que par des correctifs de proximité. Le correctif de proximité inséré dans le cadre des règles spéciales protectrices de conflit de lois participe non seulement à la fonction principale de la règle de conflit de droit, à savoir la désignation de la compétence du système juridique le plus étroitement lié au contrat, mais également à la création et au fonctionnement de ce marché intérieur espace de liberté, de sécurité et de justice / The “internal market" generates international contracts within and outside Europe. The proliferation of these contracts in fact requires an internal market established as an "area of freedom, security and justice". Regulation "Rome I", instrument of private international and European law, displays the purpose of ensuring the contractual freedom and legal security per elaborating general rules of conflict of laws. The will of the European legislator to ensure contractual justice within the internal market give rise thus, to special rules of conflict of laws that protect the contracting parties in a weak position face their co-contractor in dominant position. Regulation "Rome I" consecrates conflict of laws rules protecting the interests of certain contracting parties, that it considers that they are "weak parties"; they are the workers, the consumers, the passengers traveling to or from their country of residence, the policyholders of mass risks located on European territory, as well as distributors and franchisees. However, the success of the internal market requires achieving a balance between contractual justice, contractual freedom and legal security, even under protective special rules of conflict of laws. This balance can be achieved by correctives of proximity. The corrective of proximity inserted as part of the protective special rules of conflict of laws not only participates in the main function of the rule of law conflict, namely the designation of the competence of the legal system most closely related to the contract, but also to the establishment and operation of an internal market, area of freedom, security and justice
227

多變量d轉換的一些應用 / Some applications of multivariate d-transformations

郭錕霖 Unknown Date (has links)
Jiang (1997) 首先提出多變量d轉換與其性質。利用多變量d轉換,我們可以定義新式的特徵函數,並且稱它們是多變量d特徵函數。在這篇論文中,我們將使用多變量d特徵函數來證明在普通的條件下,Dirichlet隨機向量的線性組合會分配收斂(converge in distribution)到一個對稱的分配。此外,當給定一個分配函數的多變量d特徵函數,我們將建構一個方法來決定此分配函數。另一方面,我們將證明多變量d特徵函數擁有很多類似傳統的特徵函數的性質。 / A multivariate d-transformation and its properties were first given by Jiang (1997). By means of the multivariate d-transformations, we can define new kinds of characteristic functions and call them multivariate d-characteristic functions. In this thesis, we will use the multivariate d-characteristic function to show that the linear combinations of Dirichlet random vectors, under regularity conditions, converge in distribution to a spherical distribution. Moreover, We will construct a method for constructing the distribution function with a given multivariate d-characteristic function. In addition, we will show that the multivariate d-characteristic function has many properties which are similar to those of the traditional characteristic function.
228

CD31(-) HipOps - A Highly Osteogenic Cell Population From Mouse Bone Marrow

McKenzie, Kristen Penny 04 December 2012 (has links)
Multipotent mesenchymal stem cells (MSCs), found in many adult tissues, may be useful for regenerative medicine applications. Their identification and purification have been difficult due to their low frequency and lack of unambiguous markers. Using a magnetic micro-beads negative selection technique to remove contaminating hematopoietic cells from mouse bone marrow stromal cells (BMSCs), our lab recently isolated a highly purified osteoprogenitor (HipOp) population that was also enriched for other mesenchymal precursors, including MSCs (Itoh and Aubin, 2009). To further enhance enrichment, we positively selected BMSCs and HipOps for CD73, a putative MSC marker, which resulted in no significant additional enrichment for osteoprogenitors when the population was tested in vitro. However, we also found that HipOps were enriched in vascular endothelial cells, and that removing these cells by further negative selection with CD31/PECAM resulted in a CD31(-) HipOp population with higher osteogenic capacity than HipOps in vitro and in vivo.
229

CD31(-) HipOps - A Highly Osteogenic Cell Population From Mouse Bone Marrow

McKenzie, Kristen Penny 04 December 2012 (has links)
Multipotent mesenchymal stem cells (MSCs), found in many adult tissues, may be useful for regenerative medicine applications. Their identification and purification have been difficult due to their low frequency and lack of unambiguous markers. Using a magnetic micro-beads negative selection technique to remove contaminating hematopoietic cells from mouse bone marrow stromal cells (BMSCs), our lab recently isolated a highly purified osteoprogenitor (HipOp) population that was also enriched for other mesenchymal precursors, including MSCs (Itoh and Aubin, 2009). To further enhance enrichment, we positively selected BMSCs and HipOps for CD73, a putative MSC marker, which resulted in no significant additional enrichment for osteoprogenitors when the population was tested in vitro. However, we also found that HipOps were enriched in vascular endothelial cells, and that removing these cells by further negative selection with CD31/PECAM resulted in a CD31(-) HipOp population with higher osteogenic capacity than HipOps in vitro and in vivo.
230

Adaptive Envelope Protection Methods for Aircraft

Unnikrishnan, Suraj 19 May 2006 (has links)
Carefree handling refers to the ability of a pilot to operate an aircraft without the need to continuously monitor aircraft operating limits. At the heart of all carefree handling or maneuvering systems, also referred to as envelope protection systems, are algorithms and methods for predicting future limit violations. Recently, envelope protection methods that have gained more acceptance, translate limit proximity information to its equivalent in the control channel. Envelope protection algorithms either use very small prediction horizon or are static methods with no capability to adapt to changes in system configurations. Adaptive approaches maximizing prediction horizon such as dynamic trim, are only applicable to steady-state-response critical limit parameters. In this thesis, a new adaptive envelope protection method is developed that is applicable to steady-state and transient response critical limit parameters. The approach is based upon devising the most aggressive optimal control profile to the limit boundary and using it to compute control limits. Pilot-in-the-loop evaluations of the proposed approach are conducted at the Georgia Tech Carefree Maneuver lab for transient longitudinal hub moment limit protection. Carefree maneuvering is the dual of carefree handling in the realm of autonomous Uninhabited Aerial Vehicles (UAVs). Designing a flight control system to fully and effectively utilize the operational flight envelope is very difficult. With the increasing role and demands for extreme maneuverability there is a need for developing envelope protection methods for autonomous UAVs. In this thesis, a full-authority automatic envelope protection method is proposed for limit protection in UAVs. The approach uses adaptive estimate of limit parameter dynamics and finite-time horizon predictions to detect impending limit boundary violations. Limit violations are prevented by treating the limit boundary as an obstacle and by correcting nominal control/command inputs to track a limit parameter safe-response profile near the limit boundary. The method is evaluated using software-in-the-loop and flight evaluations on the Georgia Tech unmanned rotorcraft platform- GTMax. The thesis also develops and evaluates an extension for calculating control margins based on restricting limit parameter response aggressiveness near the limit boundary.

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