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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.
91

Résolution numérique en électromagnétisme statique de problèmes aux incertitudes géométriques par la méthode de transformation : application aux machines électriques

Mac, Duy Hung 15 March 2012 (has links) (PDF)
Les modèles numériques, de plus en plus utilisés en tant que prototypes virtuels, requièrent la connaissance de paramètres d'entrée comme les dimensions géométriques, les caractéristiques physiques des matériaux et les sollicitations externes. Les modèles numériques disponibles actuellement sont très proches de la physique qu'il représente et les écarts que l'on constate avec la réalité peuvent maintenant incomber en partie à une méconnaissance des paramètres d'entrée. L'approche probabiliste qui consiste à modéliser les quantités incertaines par des variables ou champs aléatoires est la solution qui a été retenue dans cette thèse pour prendre en compte les incertitudes d'origine géométrique. Pour résoudre le problème, la méthode de transformation, permettant de ramener un problème aux incertitudes portées par la géométrie à un problème aux incertitudes portées par les lois de comportement, a été choisie. Comme il existe une infinité de transformations possibles, différentes méthodes de détermination de la transformation ont été mises en œuvre et comparées. En particulier, un estimateur d'erreur a-priori a été proposé de manière à dégager des critères de choix. Il a été aussi montré que la méthode de transformation peut prendre en compte naturellement des discontinuités au niveau stochastique des grandeurs locales. Enfin, la méthode étudiée a été employée pour étudier l'influence des incertitudes géométriques d'un stator sur les performances d'une machine électrique. Cette étude s'appuie sur un ensemble de mesures faites sur un lot de stators.
92

A Cross-cultural Investigation Of Obsessive Compulsive Disorder Symptomatology: The Role Of Religiosity And Religious Affiliation

Altin, Mujgan 01 March 2009 (has links) (PDF)
The main aim of the present study was to better understand the influence of nationality/religious affiliation and degree of religious devoutness on OCD symptoms, more specifically scrupulosity symptoms and beliefs by comparing the Turkish Muslim students with the Canadian Christians who show different degrees of religiosity. To clarify the effect of religiosity on OCD symptomatology, Bible school and Divinity school students were included in the present study as an extreme religious group. Furthermore, the present study was aimed to examine the cross-cultural differences in the prevalence, content, appraisal and control of intrusions, using a structured interview methodology. Religiosity, guilt and scrupulosity scales and interview schedule were adapted into Turkish. The analyses revealed that the psychometric properties of the adapted measurements were satisfactory. Then, the effect of religiosity and religious affiliation on the experience of OCD symptoms, scrupulosity, and OCD relevant beliefs were examined via univariate and multivariate analyses. Results revealed that the effect of religiosity and nationality were significant for general distress. Results also revealed that regardless of nationality, high religious individuals reported higher degree of OCD and scrupulosity symptoms, and dysfunctional obsessive beliefs than low religious ones. The effect of religiosity on OCD and scrupulosity symptoms differed by religious affiliation. High religious Muslim students reported higher degree of compulsions, and fear of God symptoms than high religious Christians. Furthermore, religiosity and nationality affected obsessive beliefs differently. Turkish students reported higher level of perfectionism and intolerance for uncertainty in comparison with Canadian students. These results were supported by subsequent regression analyses. Furthermore, interview data showed that except for the frequency of the intrusions, the content of the intrusions was almost universal, and frequency and distress as a response to intrusions is very low in the normal population. Nationality and degree of religiosity revealed some minor differences in primary and secondary appraisals, and control strategies. These factors were specifically significant for religious and sexual intrusions. Results suggested that the religious affiliation and degree of religiosity may provide content for intrusions, rather being a causal factor. Keywords: Intrusive thoughts, Obsessive-Compulsive Symptoms, Faulty belief domains and appraisal, Religiosity and Religious Affiliation
93

Metodologia não intrusiva para estimação do tempo morto em sistemas monovariáveis

Kichel, Caetano Bevilacqua January 2017 (has links)
Dentre os fatores limitantes dos sistemas de controle, o tempo morto está entre os mais críticos e de difícil detecção sem testes intrusivos. O conhecimento do seu valor é essencial para a identificação de modelos e na auditoria de desempenho de sistemas de controle. Em virtude disto, o presente trabalho propõe uma metodologia eficaz para estimá-lo utilizando apenas dados históricos de processo em malha fechada. A principal vantagem frente a técnicas disponíveis na literatura é a não necessidade de testes intrusivos. A metodologia é baseada em um tratamento de sinal para remoção dos efeitos do distúrbio não medido e dos erros de modelo. O tratamento de sinal consiste na minimização das oscilações do sinal erro em malha aberta suavizado como função do tempo morto. Diversas formulações de função objetivo e procedimentos de suavização foram estudados visando facilitar a estimação do parâmetro. A qualidade da metodologia é ilustrada através de simulações em uma série de cenários, os quais simulam processos lineares de diferentes características sob o efeito de distúrbios distintos. A metodologia também é testada frente a estudo de casos com dados reais de processo industrial em malhas de nível e temperatura. Os resultados são comparados com métodos da literatura e demonstram que o método proposto foi eficaz na estimação do tempo morto para a maioria dos casos. / Among the limiting factors of control systems, the pure time delay is one of the most critical and difficult to estimate without an intrusive perturbation. The knowledge of its value is essential for model identification and control loop performance assessment. This work proposes a methodology to determine dead time using ordinary closed loop operating data. The main advantage over available techniques is the non-necessity of intrusive plant tests. The proposed approach is based on a signal processing for removing the effects of the unmeasured disturbances and the model-plant mismatches. The signal processing consists of the minimization of the oscillations of the smoothing open loop error as a function of the pure time delay. Several objective function formulations and smoothing procedures were studied in order to facilitate parameter estimation. The quality of the methodology is illustrated by simulations in a series of scenarios, which simulate linear processes of different characteristics under the effect of different disturbances. The methodology is also tested in case studies with real industrial process data. Results are compared to literature approaches and show the method was effective to estimate the pure time delay for most cases.
94

Geoquímica e geocronologia U-Pb (SHRIMP) de granitos da região de Peixoto de Azevedo – província aurífera de Alta Floresta – MT

Silva, Fernanda Rodrigues da 31 January 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-12-14T13:35:40Z No. of bitstreams: 1 DISS_2014_Fernanda Rodrigues da Silva.pdf: 4070364 bytes, checksum: 337158a8e4e32ed7d1d09d107c9ac78e (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-02-02T15:36:34Z (GMT) No. of bitstreams: 1 DISS_2014_Fernanda Rodrigues da Silva.pdf: 4070364 bytes, checksum: 337158a8e4e32ed7d1d09d107c9ac78e (MD5) / Made available in DSpace on 2018-02-02T15:36:34Z (GMT). No. of bitstreams: 1 DISS_2014_Fernanda Rodrigues da Silva.pdf: 4070364 bytes, checksum: 337158a8e4e32ed7d1d09d107c9ac78e (MD5) Previous issue date: 2014-01-31 / A análise de dados petrográficos, geoquímicos e geocronológicos de granitos da região de Peixoto de Azevedo-MT, na porção leste da Província Aurífera de Alta Floresta, conduziu ao reconhecimento de dois corpos graníticos limitados por grandes falhamentos e zonas de cisalhamento regionais. Na porção noroeste, ocorre um corpo com dimensões de aproximadamente 50 km², caracterizado como biotita granodiorito, de granulação grossa, textura inequigranular a porfirítica, metaluminoso à peraluminoso, cálcio-alcalino de alto potássio e magnesiano. Na porção sudeste da área, ocorre um corpo com aproximadamente 100 Km², caracterizado como biotita monzogranito, de granulação grossa, textura equigranular a porfiritica, levemente peraluminoso, cálcico-alcalino de alto potássio e caráter dominantemente ferroso. Datações U-Pb (SHRIMP em zircão) realizadas neste trabalho, mostraram que o biotita monzogranito apresenta uma idade de 1869±10 Ma, o que permitiu incluí-lo como parte da Suíte Intrusiva Matupá, enquanto o biotita granodiorito apresentou idade de 1761±12 Ma, cronocorrelata a idade da Suíte Intrusiva Teles Pires. Entretanto devido as variações composicionais, manteve-se para o granodiorito a denominação de Granito Peixoto. As duas unidades mostram padrões de Elementos Terras Raras com enriquecimento de leves sobre pesados e anomalia negativa de Eu (Lan/Ybn  7,6 a 17,31 e razões Eu/Eu* entre 0,46-0,72 para o biotita monzogranito e Lan/Ybn  7,13 a 29,09 com razões Eu/Eu* entre 0,25-0,40 para o biotita granodiorito). Os elementos-traço para ambos, apresentam anomalias negativas de Ba, P, Ti e Nb indicando uma evolução por fracionamento mineral onde há participação de plagioclásio, apatita e titanita e ou ilmenita, onde a anomalia negativa de Nb está relacionada a herança de placas subductadas. Duas hipóteses são sugeridas para os granitos da região. A primeira supõe que o arco magmático denominado Juruena, inicia com a formação dos granitos da Suíte Intrusiva Matupá (1870 Ma) e prossegue até a idade do granodiorito Peixoto (1761 Ma). A variação composicional gerada no período de 1870 Ma até 1761 Ma é justificada pela presença de uma crosta heterogênea, retrabalhada durante a subducção. A segunda hipótese considera que apenas o monzogranito foi gerado em ambiente de margem continental ativa, num estágio maduro. O granodiorito provavelmente teria se originado em estágio pós-colisional, como resultado de fusão de placa litosférica delaminada, seguida de contaminação crustal. A primeira hipótese têm como base a ausência de evidências de zonas colisionais na região. Entretanto na hipótese 2, considera-se que a ausência de assinaturas colisionais pode estar relacionada à baixa taxa de exumação crustal ou a carência de estudos geológicos. / The analysis of petrographic, geochemical and geochronological data of granites in the region of Peixoto de Azevedo - MT, in the eastern portion of the Alta Floresta Gold Province, led to the recognition of two granitic bodies bounded by major faults and shear zones in the region. In the northwestern portion, a body with dimensions of approximately 50 km ², featured as biotite granodiorite , coarse-grained , porphyritic texture inequigranular to, metaluminous to peraluminous, calc- alkaline high potassium and magnesium occurs. In the southeastern portion of the area, a body with approximately 100 Km ², featured as biotite monzogranite, coarse-grained, equigranular to porphyritic texture, slightly peraluminous, calc- alkaline high potassium and occurs dominantly ferrous character. U- Pb dating ( SHRIMP zircon ) in this work showed that the biotite monzogranite has an age of 1869 ± 10 Ma, which allowed to include it as part of Intrusive Suite Matupá, while the biotite granodiorite had age 1761 ± 12 Ma, cronocorrelata age Intrusive Suite Teles Pires. However due to compositional variations, remained for the designation of granodiorite Granite Peixoto. Both units show patterns of Rare Earth Elements with enrichment of light over heavy and negative Eu anomaly ( Lan / YBN  7.6 to 17.31 and ratios Eu / Eu * between 0.46 to 0.72 for biotite monzogranite and Lan / YBN  7.13 to 29.09 with ratios Eu / Eu * between 0.25-0.40 for the biotite granodiorite ). Trace elements for both present negative anomalies of Ba, P, Ti and Nb indicating an evolution for mineral fractionation where there is involvement of plagioclase, apatite and titanite and ilmenite or where the negative Nb anomaly is related to inheritance subductadas plates. Two hypotheses are suggested to the granites of the region. The first assumes that the magmatic arc called Juruena, begins with the formation of granites Intrusive Suite Matupá (1870 Ma ) and continues until the age of granodiorite Peixoto ( 1761 Ma ). The compositional variation generated in the period from 1870 Ma to 1761 Ma is justified by the presence of a heterogeneous crust reworked during subductio. The second hypothesis considers that only the monzogranite was generated in active continental margin environment, in a mature stage. The granodiorite probably would have originated in post -collisional stage, as a result of fusion of delaminated lithospheric plate , followed by crustal contamination. The first hypothesis are based upon the absence of evidence for collisional zones in the region. However in case 2, it is considered that the absence of collisional signatures may be related to the low rate of crustal exhumation or the lack of geological studies.
95

Metodologia não intrusiva para estimação do tempo morto em sistemas monovariáveis

Kichel, Caetano Bevilacqua January 2017 (has links)
Dentre os fatores limitantes dos sistemas de controle, o tempo morto está entre os mais críticos e de difícil detecção sem testes intrusivos. O conhecimento do seu valor é essencial para a identificação de modelos e na auditoria de desempenho de sistemas de controle. Em virtude disto, o presente trabalho propõe uma metodologia eficaz para estimá-lo utilizando apenas dados históricos de processo em malha fechada. A principal vantagem frente a técnicas disponíveis na literatura é a não necessidade de testes intrusivos. A metodologia é baseada em um tratamento de sinal para remoção dos efeitos do distúrbio não medido e dos erros de modelo. O tratamento de sinal consiste na minimização das oscilações do sinal erro em malha aberta suavizado como função do tempo morto. Diversas formulações de função objetivo e procedimentos de suavização foram estudados visando facilitar a estimação do parâmetro. A qualidade da metodologia é ilustrada através de simulações em uma série de cenários, os quais simulam processos lineares de diferentes características sob o efeito de distúrbios distintos. A metodologia também é testada frente a estudo de casos com dados reais de processo industrial em malhas de nível e temperatura. Os resultados são comparados com métodos da literatura e demonstram que o método proposto foi eficaz na estimação do tempo morto para a maioria dos casos. / Among the limiting factors of control systems, the pure time delay is one of the most critical and difficult to estimate without an intrusive perturbation. The knowledge of its value is essential for model identification and control loop performance assessment. This work proposes a methodology to determine dead time using ordinary closed loop operating data. The main advantage over available techniques is the non-necessity of intrusive plant tests. The proposed approach is based on a signal processing for removing the effects of the unmeasured disturbances and the model-plant mismatches. The signal processing consists of the minimization of the oscillations of the smoothing open loop error as a function of the pure time delay. Several objective function formulations and smoothing procedures were studied in order to facilitate parameter estimation. The quality of the methodology is illustrated by simulations in a series of scenarios, which simulate linear processes of different characteristics under the effect of different disturbances. The methodology is also tested in case studies with real industrial process data. Results are compared to literature approaches and show the method was effective to estimate the pure time delay for most cases.
96

Development of Innovative Load Transfer Mechanism to Reduce Hurricane-Induced Failures in New and Existing Residential Construction

Ahmed, Sheikh Saad 14 January 2010 (has links)
Implicit in current design practice of minimum uplift capacity, is the assumption that the connection's capacity is proportional to the number of fasteners per connection joint. This assumption may overestimate the capacity of joints by a factor of two or more and maybe the cause of connection failures in extreme wind events. The current research serves to modify the current practice by proposing a realistic relationship between the number of fasteners and the capacity of the joint. The research is also aimed at further development of non-intrusive continuous load path (CLP) connection system using Glass Fiber Reinforced Polymer (GFRP) and epoxy. Suitable designs were developed for stud to top plate and gable end connections and tests were performed to evaluate the ultimate load, creep and fatigue behavior. The objective was to determine the performance of the connections under simulated sustained hurricane conditions. The performance of the new connections was satisfactory.
97

Intrusive Thinking in Older Adulthood: The Influence of Subjective Cognitive Concerns

Goldman, Annika Sophia 26 March 2021 (has links)
No description available.
98

Developing Bleeding-edge microservice solutions for complex problems : Non-intrusive technology in Walking Meetings / Cloudlösning baserad på mikrotjänster med bleeding-edge technology vid utveckling av interaktivt tekniskt support för gå-möten

Meenakshi Sundaram, Vignesh January 2017 (has links)
The last decade has seen an emergence of various types of cloud services and development frameworks offered by leading companies in the software industry. While each of these services has been used to solve specific tasks, their specifications have changed over time as they have matured. Therefore, integrating these components to solve a whole new task tends to get tricky due to their incompatible and experimental nature. While some technology components might continue to be developed, others might deprecate. In this thesis, using a user-centered design and agile development approach, we have attempted to develop a cloud solution using microservice software architecture by integrating state-of-the-art technology components to solve a totally new task of providing a non-intrusive technology experience during walking meetings. We present our results based on interaction with the research group, user studies as a part of the research study “Movement of the mind”, and expectations of the working prototype within the context of walking meetings. We also present the features of the prototype and our motivation for choosing the tools to develop them. Finally, we discuss the development challenges faced during our attempt and conclude whether it is plausible to integrate various components of bleeding-edge technology to solve complex real-life problems or rather wait for these technologies to mature. / Under det senaste decenniet har marknaden erbjudits en mängd olika typer av molntjänster och utvecklings-ramverk framtagna av ledande företag inom mjukvaruindustrin. Dessa tjänster har ofta använts för att lösa specifika uppgifter. Olika komponenterna som ingår i dessa specifika lösningar har med tiden utvecklats ändrats allteftersom de har mognat. Att integrera dessa komponenter för att lösa en helt ny uppgift tenderar därför att bli svårt på grund av deras instabila, inkompatibla och experimentella karaktär. Medan vissa teknikkomponenter kan fortsätta att utvecklas kan andra avstanna och utgå. Vi har närmat oss detta problemområde genom agil och iterativ utveckling samt användar-centrerad design-metod. En moln-baserad lösning som bland annat integrerat bleeding-edge teknikkomponenter har utvecklats och utvärderats med syfte att ge en icke-påträngande tekniskt support för gå-möten. De resultat som här presenteras och diskuteras baseras på interaktion med forskargruppen inom projektet "Med rörelse i tankarna", användarstudier och användartesteter i fält på olika arbetsplatser där den prototyp som utvecklats sökt motsvara användarnas utryckta förväntningar på tekniskt support för gångmöten. Vi diskuterar också prototypens egenskaper och vår motivation för val av metoder för att utveckla den. Slutligen diskuterar vi de utvecklingsutmaningar vi ställdes inför under vårt försök och om det är rimligt att integrera olika bleeding-edge komponenter för att lösa komplexa verkliga problem eller huruvida man hellre bör vänta på att dessa teknologier nått en stabilare mognadsgrad.
99

EFFECTS OF EMBEDDED INERT AND REACTIVE WIRES AND THEIR TESTING METHODS ON THE DEFLAGRATION DYNAMICS OF AN AMMONIUM PERCHLORATE COMPOSITE PROPELLANT

Usman Ashraf Bajwa (13171308) 28 July 2022 (has links)
<p> Embedding thermally conductive wires in a propellant has been known as an alternative means of increasing the burning rate of the propellant. The wires conduct heat into the propellant, preheating the material surrounding the wire and locally increasing the burning rate around the wire. As the propellant burns, a cone forms around the wire, exposing more burning surface area, which in turn increases the chamber pressure and consequently the bulk burning rate of the propellant. Likewise, embedded reactive wires have been considered in solid propellants for decades. Typically, these wires have been metal-metal reactive materials (intermetalics), but more recently metal-fluoropolymer materials have been considered. These reactive wires are consumable energetic materials that burn faster than the propellant, which allows them to expose more burning surface area by igniting the propellant faster than the burning front can proceed. Some of these reactive wire materials have also been shown to be additively manufacturable, allowing them to be printed in complex geometries, which further increases the tailorability of the burning surface profile. Previous studies on inert wires have largely focused on double base formulations, but few have considered composite propellants. These studies cast the wires against a window in order to visualize the burning that may affect the results. A few studies have also been performed with embedded reactive wires at elevated pressures, again cast against a window, which may have affected the burning dynamics by acting as an additional path for heat loss. This work studied whether the window affected the deflagration dynamics of embedded wire samples by comparing the combustion of windowed samples to full strand samples with propellant surround all sides of the wire and visualized with dynamic X-rays. High purity copper and silver wire were embedded in diameters of 0.405, 0.644, and 0.812 mm (26, 22, and 20 AWG) as inert, thermally conductive wires. A 20 wt. % active nanoscale aluminum and polyvinylidene fluoride reactive wire extruded using a 1.6 mm nozzle was also embedded for comparison to the inert wires. The windowed samples were tested in open air and in a Crawford strand burner at elevated pressures, using a high speed camera to view how the deflagration progressed along the wire against the window. The full strand samples were tested in open air using X-ray radiography to view the cone forming around the embedded wire. A burning rate enhancement was able to be measured from the burning profile around the wire. No statistically significant differences between the average measurements of windowed samples and full strand samples were found except in the case of 20 AWG Ag wire. The burning rate enhancement of the reactive wire was found to increase with increasing pressure, whereas the inert wires showed a decrease in burning rate enhancement. This effect is due to the reaction rate of the reactive wire increasing with pressure, whereas heat conduction along a metal wire is not dependent on pressure. </p>
100

Intrusive stop formation in Zulu : an application of Feature Geometry Theory

Naidoo, Shamila 12 1900 (has links)
Thesis (DLitt (African Languages))--University of Stellenbosch, 2005. / This study investigates the Intrusive Stop Formation process in Zulu. In this process an intrusive stop arises when a nasal and fricative are juxtaposed resulting in the following seven affricate sounds /þf’, {v, ts’, dz, tñ’, dL, tS’/. These sounds are theoretically distinct from the four affricate phonemes which occur in Zulu, namely /kl’, dZ, ts’, tS’/. In this study the former are termed derived affricates and the latter pure affricates. Two aspects of Intrusive Stop Formation are focused on - firstly, determining experimentally whether durational differences obtain between pure and derived affricates and secondly, using the results of the experimental investigation to facilitate a feature geometry description of the Intrusive Stop Formation process. In the experimental investigation nine affricate sounds were examined. Words, containing these sounds, were recorded in frame sentences by five speakers, using PRAAT, a speech–processing platform. The duration of the pure and derived affricates were then determined. It was found that pure affricates are durationally longer than derived affricates. The next progression in this study was the incorporation of the experimental results into a feature geometry description of Intrusive Stop Formation. Feature Geometry Theory has enjoyed acclaim because of its ability to retain Distinctive Feature Theory – the crux of Phonology – in a nonlinear framework. However, Feature Geometry Theory faces challenges with regard to the extent to which it includes phonetic detail; and its formalization technique. This study – Intrusive Stop Formation in Zulu : An Application of Feature Geometry Theory – brings a new perspective to Feature Geometry Theory with the incorporation of the Duration tier – significant for the description of the Intrusive Stop Formation process. Furthermore the study introduces a more efficient formalization technique, which facilitates the explanation of the process. It is always incumbent upon endeavours like this study, which examine specific phonological processes, to show relevance. In the concluding section the application of the experimental approach and Feature Geometry Theory is evaluated in terms of the contribution made to the disciplines of Human Language Technology and Speech Disorders. A compact disk accompanies this thesis. It contains the sound files, spectrograms and textgrids of the recorded data.

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