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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.
51

A study of Polya's enumeration theorem

Williams, Elizabeth C., January 2005 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.
52

New quartet methods in phylogenetic combinatorics /

Weyer-Menkhoff, Jan. January 2003 (has links)
Univ., Diss.--Bielefeld, 2003.
53

Influência da configuração e do bisel em esmalte bovino, nos preparos cavitários de classe v, para restaurações de resina composta compactável: estudo in vitro da infiltração marginal

Carvalho, João Cândido de [UNESP] 29 May 2001 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-05-29Bitstream added on 2014-06-13T21:05:37Z : No. of bitstreams: 1 carvalho_jc_dr_sjc.pdf: 1291097 bytes, checksum: 3655dbb3a350164b05f1b07f8285520c (MD5) / O objetivo deste trabalho foi avaliar o selamento em cavidades de classe V localizadas em esmalte de dentes bovinos, empregando-se teste de microinfiltração, levando-se em consideração os fatores, configuração do preparo cavitário, o tratamento das paredes de esmalte com a presença ou não de bisel e o emprego de uma resina fluida associada a uma resina campactável. Foram selecionados 80 dentes bovinos, limpos, seccionados os terços apicais, removendo-se a polpa radicular e coronária e irrigados com soro fisiológico. Os ápices foram vedados com resina composta e os dentes receberam uma base de resina acrílica e foram conservados em freezer a -18ºC até o momento de uso. Após os preparos, os mesmos foram restaurados, usando-se condicionamento ácido/adesivo Prime Bond NT, resina compactável SureFil -Dentsply LD Caulk Co e em metade dos corpos-de-prova a resina fluida - Flow It - Jeneric Pentron. Os corpos-de-prova foram termociclados à temperatura de 5ºC l 2ºC e 55ºC l 2ºC por 30s, e após, imersos em Rodamina B 2% por 24h; lavagem em água corrente por 20min para remoção do corante e secagem. Em uma cortadeira foram realizados dois cortes no sentido vestíbulo lingual para avaliação em estereomicroscópio por dois observadores, que atribuíram escores de acordo com os graus de infiltração marginal. Foram empregados os métodos estatísticos Kruskal-Wallis não paramétricos, comparação múltipla de Tukey e Mann-Whitney com nível de significância de 5%. A metodologia empregada para avaliar a infiltração marginal permitiu concluir que: 1- a configuração do preparo cavitário (grupos I e III) não influencia o grau de infiltração marginal; 2- a presença de bisel, para o preparo em forma de caixa (grupo II) mostrou melhora de comportamento, com redução estatisticamente significante do grau de infiltração marginal... / The aim of this study was to evaluate the class V cavity sealing located in enamel of bovine teeth using microleakage tests considering the factors, cavity preparation configuration, enamel walls treatment with or without the bevel and the use of a flow composite resin together with a packable composite resin. Eighty clean bovine teeth, seccioned on the apical third without the root and coronary pulp were used. The apex were sealed with composite resin and the teeth were embedded in an acrylic resin and stored in freezer at a temperature of –18oC until the moment of their use. After the cavity preparation the teeth were filled using the acid/adhesive etching Prime Bond NT, Surefill Dentsply LD Caulk packable composite resin and Flow It – Generic Pentron – composite resin. Then the specimens suffered temperature cycles of 5oC ± 2oC and 55oC± 2oC for 30 seconds, and after that they were immersed in Rodamin B 2% dye for 24 hours followed by water rinsing and drying. Two buccal lingual sections were made to be evaluated by two observers using a stereomicroscope. The two observers attributed scores to the marginal leakage degrees. Non parametric Kruskal Wallis and the multiple comparison Tukey an Mann-Whitney statistical tests with 5% significance were utilized. Through this methodology it is possible to conclude that: 1. Groups I and III did not show differences according to marginal microleakage regarding the cavity preparation configurations; 2. the bevel presence for the conventional cavity preparation (groups I and II) showed better results with statistically significant marginal leakage degree reduction; 3. the bevel presence for the tear drop cavity preparation (groups III and IV) did not show better results according to the statistical methods; the use of the flow composite was favorable only for group III (tear drop cavity preparation without bevel); 5. the best results were observed on the group II.
54

Influência da configuração e do bisel em esmalte bovino, nos preparos cavitários de classe v, para restaurações de resina composta compactável : estudo "in vitro" da infiltração marginal /

Carvalho, João Candido de. January 2001 (has links)
Resumo : O objetivo deste trabalho foi avaliar o selamento em cavidades de classe V localizadas em esmalte de dentes bovinos, empregando-se teste de microinfiltração, levando-se em consideração os fatores, configuração do preparo cavitário, o tratamento das paredes de esmalte com a presença ou não de bisel e o emprego de uma resina fluida associada a uma resina campactável. Foram selecionados 80 dentes bovinos, limpos, seccionados os terços apicais, removendo-se a polpa radicular e coronária e irrigados com soro fisiológico. Os ápices foram vedados com resina composta e os dentes receberam uma base de resina acrílica e foram conservados em freezer a -18ºC até o momento de uso. Após os preparos, os mesmos foram restaurados, usando-se condicionamento ácido/adesivo Prime Bond NT, resina compactável SureFil -Dentsply LD Caulk Co e em metade dos corpos-de-prova a resina fluida - Flow It - Jeneric Pentron. Os corpos-de-prova foram termociclados à temperatura de 5ºC l 2ºC e 55ºC l 2ºC por 30s, e após, imersos em Rodamina B 2% por 24h; lavagem em água corrente por 20min para remoção do corante e secagem. Em uma cortadeira foram realizados dois cortes no sentido vestíbulo lingual para avaliação em estereomicroscópio por dois observadores, que atribuíram escores de acordo com os graus de infiltração marginal. Foram empregados os métodos estatísticos Kruskal-Wallis não paramétricos, comparação múltipla de Tukey e Mann-Whitney com nível de significância de 5%. A metodologia empregada para avaliar a infiltração marginal permitiu concluir que: 1- a configuração do preparo cavitário (grupos I e III) não influencia o grau de infiltração marginal; 2- a presença de bisel, para o preparo em forma de caixa (grupo II) mostrou melhora de comportamento, com redução estatisticamente significante do grau de infiltração marginal...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the class V cavity sealing located in enamel of bovine teeth using microleakage tests considering the factors, cavity preparation configuration, enamel walls treatment with or without the bevel and the use of a flow composite resin together with a packable composite resin. Eighty clean bovine teeth, seccioned on the apical third without the root and coronary pulp were used. The apex were sealed with composite resin and the teeth were embedded in an acrylic resin and stored in freezer at a temperature of -18oC until the moment of their use. After the cavity preparation the teeth were filled using the acid/adhesive etching Prime Bond NT, Surefill Dentsply LD Caulk packable composite resin and Flow It - Generic Pentron - composite resin. Then the specimens suffered temperature cycles of 5oC ± 2oC and 55oC± 2oC for 30 seconds, and after that they were immersed in Rodamin B 2% dye for 24 hours followed by water rinsing and drying. Two buccal lingual sections were made to be evaluated by two observers using a stereomicroscope. The two observers attributed scores to the marginal leakage degrees. Non parametric Kruskal Wallis and the multiple comparison Tukey an Mann-Whitney statistical tests with 5% significance were utilized. Through this methodology it is possible to conclude that: 1. Groups I and III did not show differences according to marginal microleakage regarding the cavity preparation configurations; 2. the bevel presence for the conventional cavity preparation (groups I and II) showed better results with statistically significant marginal leakage degree reduction; 3. the bevel presence for the tear drop cavity preparation (groups III and IV) did not show better results according to the statistical methods; the use of the flow composite was favorable only for group III (tear drop cavity preparation without bevel); 5. the best results were observed on the group II. / Orientador: Maria Amélia Máximo de Araújo / Coorientador: Clóvis Pagani / Banca: Maria Amélia Máximo de Araújo / Banca: Mitio Miura / Banca: Maria Antonia Pereira / Banca: José Roberto Rodrigues / Banca: Newton José Giachetti / Doutor
55

Approches pour la gestion de configurations de sécurité dans les systèmes d'information distribués / Techniques for security configuration management in distributed information systems

Casalino, Matteo Maria 02 July 2014 (has links)
La sécurité des services informatiques d'aujourd'hui dépend significativement de la bonne configuration des systèmes qui sont de plus en plus distribués. Au même temps, la gestion des configurations de sécurité est encore fortement basée sur des activités humaines, qui sont coûteuses et sujettes à erreurs. Au cours de la dernière décennie, il a été reporté à plusieurs reprises qu'une partie significative des incidents de sécurité et des pertes de données a été causée par des configurations incorrectes des systèmes. Pour résoudre ce problème, plusieurs techniques ont été proposées pour automatiser les tâches de gestion des configurations. Beaucoup d'entre elles mettent l'accent sur les phases de planification et de mise en œuvre, où les exigences et les politiques de sécurité abstraites sont conçues, harmonisées et transformées dans des configurations concrètes. Ces techniques nécessitent souvent d'opérer sur des politiques formelles ou très structurées qui se prêtent à un raisonnement automatisé, mais qui sont rarement disponibles dans la pratique. Cependant, moins d'attention a été consacrée aux phases de gestion de suivi et de changement des configurations, qui complètent les étapes précédentes en détectant et en corrigeant les erreurs afin d'assurer que les changements de configuration n'exposent pas le système à des menaces de sécurité. Les objectifs et les contributions de cette thèse se concentrent sur ce deuxième point de vue, de façon pragmatique sur la base des configurations de sécurité concrètes. En particulier, nous proposons trois contributions visant à analyser et à vérifier des configurations de sécurité / The security of nowadays IT services significantly depends on the correct configuration of increasingly distributed information systems. At the same time, the management of security configurations is still heavily centered on human activities, which are costly and prone to error. Over the last decade it has been repeatedly reported that a significant share of security incidents and data breaches are caused by inaccurate systems configuration. To tackle this problem, several techniques have been proposed to increase the automation in configuration management tasks. Many of them focus on planning and implementation, i.e., the phases where abstract security requirements and policies are elicited, harmonized, de-conflicted and transformed into concrete configurations. As such, these techniques often require formal or highly structured input policies amenable to automated reasoning, which are rarely available in practice. In contrast, less attention has been dedicated to the monitoring and change management phases, which complement the above steps by detecting and remediating configuration errors and by ensuring that configuration changes do not expose the system to security threats. The objectives and contributions of this thesis take the latter perspective and, as such, they pragmatically work on the basis of concrete security configurations. In particular, we propose three contributions that move from more concrete syntax-based configuration analysis towards increasingly abstract semantic reasoning
56

Design of Shape-Morphing Structures Consisting of Bistable Compliant Mechanisms

Alfattani, Rami 25 March 2019 (has links)
This dissertation presents a design concept for shape-morphing structures that have two stable configurations. The design concept defines the methodology of transforming a planar structural shape into spatial structural shape using bistable compliant mechanisms. Bistable complaint mechanisms are used to achieve structural stable configurations. The dissertation incorporating geometrical relationships for the mechanisms that form the primary structure described in step-by-step process. This dissertation implements the design layouts for designer to creating shape-morphing structures including origami. The novel contribution of the work is classified in three models. The first model presents a methodology to induce bistability behavior into an origami reverse fold and partially spherical compliant mechanism. The second model presents the design and development of a bistable triangle-shaped compliant mechanism with motion limits and dwell behavior at the two stable configurations. This mechanism can be arrayed to create shape-morphing structures. The third model presents a design and development for a collapsible bistable compliant mechanism used for a shape morphing lamina-emergent frustum. Finally, physical prototypes of all models are presented as proof of concept.
57

Species Tree Likelihood Computation Given SNP Data Using Ancestral Configurations

Fan, Hang January 2013 (has links)
No description available.
58

Nonverbal interaction in small groups: a methodological strategy for studying process

Fitzpatrick, Donna Lee January 1974 (has links)
No description available.
59

Some results on the association schemes of bilinear forms /

Huang, Tayuan January 1985 (has links)
No description available.
60

Gauge fixed gluonic observables and neutral kaon mixing on the lattice

Hudspith, Renwick January 2013 (has links)
This thesis presents gauge fixed gluonic observable and neutral Kaon mixing matrix element measurements using nf=2+1 Domain Wall Fermion (DWF) configurations. These were generated with the Iwasaki gauge action by the RBC and UKQCD collaborations. Results from the first measurement of the QCD strong coupling with these ensembles using the triple gluon vertex are shown. We find that while a very accurate measurement of the coupling is possible using this technique, the systematic error from the perturbative matching at current lattice scales is large. We also discuss the utilisation of this method as a probe for possible Technicolor theories. The calculation of the QCD strong coupling constant from the triple gluon vertex required an implementation of a fast code to fix lattice gauge configurations. I provide details on my implementation of a parallel and optimised Fourier-accelerated algorithm for both Landau and Coulomb gauge fixing. I include the first calculation of the highly accurate W0-scale using these ensembles, allowing for percent-level scale setting. I show results from a wide variety of smearing methods and present the first gluonic measurement of different smearing radii. This thesis also details the first nf=2+1 measurement of the BSM neutral Kaon mixing renormalised matrix elements from lattice simulations with almost exact chiral symmetry in the valence sector and the sea.

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