Le GNSS est actuellement présent dans de nombreux domaines et permet le positionnement et la navigation. Parmi ces domaines, l’aviation civile a besoin d’une qualité de service élevée, notamment pendant les phases de vol les plus exigeantes en termes d’intégrité, de précision, de disponibilité et de continuité. Afin de satisfaire ces exigences, toutes les sources de dégradations potentielles du service doivent être prises en compte. Les distorsions des signaux GNSS générées par la charge utile du satellite sont un exemple de problème qui doit être pris en compte par l’aviation civile. Elles peuvent se manifester de deux manières différentes: les distorsions nominales générées par les satellites en fonctionnement normal et les distorsions non nominales générées lors d’une panne de la charge utile. Tout d’abord, cette thèse aborde le problème des déformations nominales affectant les signaux GPS L1 C/A et Galileo E1C. Différentes observations sont réalisées à partir de la visualisation de la fonction de corrélation ou du signal et par l’utilisation d’antennes à haut gain et d’une antenne omnidirectionnelle. Après l’observation des distorsions nominales, cette thèse aborde le sujet des distorsions non nominales du signal. En utilisant les travaux réalisés dans le passé par l’aviation civile dans le cadre du signal GPS L1 C/A, le but est de proposer de nouveaux modèles de distorsions associés aux nouveaux signaux GPS et Galileo qui vont être utilisés par l’aviation civile après 2020. Dans cette optique, de nouveaux modèles de menace (appelés TMs) pour les nouveaux signaux (GPS L5 et Galileo E5a et E1C) sont proposés. La dernière étape de cette thèse se focalise sur l’étude d’une technique capable de protéger un utilisateur de l’aviation civile contre les TMs proposés pour les nouveaux signaux. Cette technique appelée SQM est aujourd’hui implémentée dans les systèmes GBAS et SBAS pour détecter les distorsions de la fonction de corrélation dans le cadre des signaux GPS L1 C/A. / GNSS is used nowadays in various fields for navigation and positioning including safety -of-life applications. Among these applications is civil aviation that requires a very high quality of service for the most demanding phases of flight in terms of integrity, accuracy, availability and continuity. To meet these requirements any source of potential service degradations has to be accounted for. One such example is GNSS signal distortions due to the satellite payload which can manifest in two ways: nominal distortions that are generated by healthy satellites due to payload imperfections and nonnominal distortions that are triggered by a satellite payload failure. The thesis first looks at the nominal distortions through GPS L1 C/A and Galileo E1C signals. Different types of observations are used based on correlation or chip domain visualization, and using high-gain and omnidirectional antennas. After the observation of nominal distortions, the dissertation investigates the non-nominal distortions due to the payload failure. Supported by the groundwork performed by civil aviation on signal distortion for the GPS L1 C/A signal, this dissertation aims at proposing new distortions models associated to the new GPS and Galileo signals that will be used by civil aviation after 2020. In particular, new TMs for new signals (GPS L5, Galileo E5a and Galileo E1C) are proposed. Finally, in this dissertation is built an appropriate monitor, referred to as SQM that is able to detect any distortion from the proposed TMs (for new signals) that could lead to a position integrity failure. Regarding GPS L1 C/A signal monitoring, such SQM is today implemented in GNSS augmentation systems including GBAS and SBAS. The current monitors are based on the analysis of the correlation function.

Made available in DSpace on 2014-06-11T19:28:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-24Bitstream added on 2014-06-13T20:17:58Z : No. of bitstreams: 1 coraini_r_me_bauru.pdf: 4046838 bytes, checksum: 246be85a1178880a9bdc9bbb5df7fbde (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização do alumínio em escala industrial vem crescendo cada vez mais nos últimos anos e um dos principais motivos é o espaço que esse material vem conquistando em substituição ao aço. O interesse da indústria em ter um maior controle das distorções provocadas pela soldagem de alumínio se deve ao fato das tolerâncias dimensionais e geométricas estarem cada vez mais precisas nas especificações de projeto, motivando a engenharia de fabricação a desenvolver processos estáveis e que garantam a rotina de produção. O elevado coeficiente de expansão linear desse metal, se comparado ao aço, é uma das suas principais características que geram dificuldades nesse cenário. Visando isso, o presente trabalho tem como principal objetivo analisar o quanto situações rotineiras utilizadas na soldagem robotizada de alumínio podem influenciar nas distorções angulares deste material, sem comprometer a integridade mecânica da junta soldada e com confiabilidade estatística. Utilizando a liga AA 5052 H34, e a soldagem robotizada no processo GMAW pulsado, foram aplicados três tipos de tecimento ao longo do comprimento da solda, em juntas de topo montadas sem chanfro e com chanfro de 60º, dispostas tanto transversais quanto longitudinais ao sentido de conformação da chapa. A medição das distorções foi realizada por um braço tridimensional, antes e após a soldagem, em três regiões distintas nos corpos de prova. O perfil do cordão de solda foi o fator determinante para as diferentes formas das distorções encontradas, assim como revelado pelas análises macrográficas. A junta com chanfro de 60º apresentou maiores amplitudes das distorções que a junta sem chanfro. O tecimento não foi uma variável de influência estatística significativa nessas amplitudes. Ensaios de tração foram realizados para se avaliar o comportamento mecânico das juntas soldadas / The use of aluminum by industry has been recently growing more and more each time and one of the main reasons is the position that this material is gaining as a replacement for steel. The industry's interest in having a greater control of the distorcions caused by aluminum welding is due to the geometric and dimensional tolerances been more and more precise in the project specifications, motivating the manufacturing engineering to develop stable processes and to ensure routine production. The high coefficient of linear expansion of this metal, which is one of its main features, can create a difficult scenario when compared to the steel. Aiming at it, the main goal of this present work is to analyze how much routine situations used int the robotic aluminum welding can influence in the angular distortions of this material, without affecting the mechanical integrity of the welded joint and with statistical reliability. Using the alloy AA 5052 H34, and the robotic welding in pulsed GMAW process, it was applied three types of weaving throughout the length of the weld, in butt joints assembled without groove and with 60º single-V-groove, arranged transversely as well as longitudinally to the rolling direction of the plate. The measurement of the distortions was made by a three-dimensional equipment, before and after the welding, in three distinct regions in the speciments. The profile of the weld bead was the main factor for the different types of distortions found, as revealed by macrographical analysis. The 60º single-V-groove had higher amplitudes of distortions as the joint without groove. The weaving wasn't a variable of statistically significant influence in this amplitudes. Tensile tests were made to evaluate the mechanical properties of the welded joints

A transformação de coordenadas entre Sistemas e/ou Redes Geodésicas é um procedimento amplamente utilizado por usuários de informações associadas a coordenadas. A posição de um móvel, feição ou corpo pode ser estabelecida em diferentes Redes, desde que se conheça os parâmetros que as interrelacionam. Do ponto de vista conceitual pode ser entendido como um problema trivial, mas na prática, sua solução é complexa. Isso decorre, basicamente, das diferentes maneiras que podem ser usadas para definir um Sistema, bem como das deformações existentes nas suas materializações, originadas pelas várias influências sistemáticas pertinentes à estimação das coordenadas. Uma metodologia para a transformação entre as duas materializações do Sistema Geodésico Brasileiro (SGB), associadas ao Sistema Geodésico SAD 69, é proposta nesta tese. A primeira, que vigorava desde o primeiro ajustamento, realizado na década de 70; e a segunda, referente ao primeiro reajustamento, terminado no ano de 1996. Doravante, para efeito somente desta pesquisa, as realizações serão denominadas SAD 69 e SAD 69/96, respectivamente. A metodologia proposta tem, como condicionante, a preservação da integridade daquelas duas realizações do SGB, de modo a garantir suas precisões e exatidões. Fundamenta-se, basicamente, em 3 etapas: 1) regionalização da Rede Geodésica Brasileira(RGB), produzida por uma Triangulação de Delaunay 3-D; 2) estimação, para cada região, dos parâmetros resultantes da aplicação de uma transformação geométrica 3-D entre os dois conjuntos de coordenadas; 3) aplicação de correções às coordenadas calculadas pela transformação geométrica Afim Geral 3-D. Adicionalmente, realizou-se um estudo sobre Sistemas e Redes de Coordenadas, enfatizando aquelas de natureza Geodésica, bem como sobre o SGB. Foi realizada ainda uma investigação sobre o reajustamento da RGB, quando foram abordados aspectos relativos à metodologia empregada e à sua exatidão. Finalmente, são apresentados os resultados dos testes executados para validação da metodologia, comprovando a viabilidade de sua aplicação. / The coordinate transformation between Reference Systems and/or Reference Frames is a procedure extensively used by users of information associate to coordinates. The position of any stationary or moving object can be established in different frames since their interrelation parameters are well known. Considering the conceptual point of view, it can be understood as a trivial problem, but in the practice, its solution is very complex. This reality results from the different possibilities in which one system can be defined, as well as of the existing deformations in the frames, originated from several influences related to the estimation of the coordinates. A methodology for transforming the coordinates between the two materializations of Brazilian Geodetic System (BGS), associated with the Geodetic System SAD 69 is proposed. The first materialization refers to the first adjustment, carried out in the 70's. The second one refers to the first readjustment, finished at the end of 1996. From now on, only for the purpose of this research, these materializations will be named SAD 69 and SAD 69/96, respectively. The proposed methodology preserves the integrity of the BGS realizations and assures their precisions and accuracies. Its foundation has three main stages: 1) partitioning of the Brazilian Geodetic Network, according to a Delaunay 3-D Triangulation; 2) estimating, for each region, parameters derived from the application of a geometric transformation between the two sets of coordinates; 3) application of corrections to the coordinates evaluated by the Affine Geometric Transformation. Additionally, a study on Geodetic Coordinate Systems and Frames and on the BGS has been carried out. An investigation on the readjustment of BGS has been achieved, where aspects refering to the used methodology and its accuracy have been taken into account.Finally, the results of the tests carried out for validation of the methodology are presented,emphasizing the reliability of its application.

Studies have been conducted in both the United States (US) and Argentina to validate the Spanish version of the Gamblers’ Beliefs Questionnaire (GBQ-S). While similar factor structures of the GBQ-S were found in these studies, more detailed measurement invariance has not been explored. Determining measurement invariance across cultural groups would aid researchers in understanding what types of comparisons on latent constructs can be validly made between cultures using the GBQ-S. A secondary analysis was completed with data from two prior studies in Spanish-speaking samples from the US and Argentina. A modified baseline model that captured the two latent factors of Illusion of Control and Luck/Perseverance was selected for invariance testing. The evaluation of measurement invariance within a structural equation modeling framework established configural and metric, but not scalar, invariance. The GBQ-S can be validly used to measure the same latent variables across groups with comparable strengths between its items and factors; however, latent mean comparisons across groups may require further measurement refinement. The GBQ-S demonstrated notable degrees of measurement invariance between markedly different samples, providing further evidence for the existence of similar constructs and portability of the GBQ-S across populations.

Le Cameroun est un pays engagé dans une stratégie de développement volontariste, faisant toutefois face à d’importantes difficultés de croissance économique et à une corruption chronique. Suivant ce contexte, la présente étude a pour objet d’effectuer une analyse théorique et empirique des effets de la corruption sur la croissance économique du Cameroun. A cet effet, notre premier axe d’analyse vise à déterminer la nature de la corrélation entre la corruption et la croissance économique au Cameroun. Notre étude révèle qu’à long terme, la corruption affecte négativement le taux de croissance économique, suivant des effets directs d’une part, et suivant des effets indirects d’autre part, à travers l’investissement privé, le niveau d’éducation et les dépenses publiques. Dès lors, un deuxième axe d’analyse nous a paru intéressant à aborder, cherchant cette fois à évaluer l’effet indirect de la corruption sur la croissance économique via les distorsions dans la répartition des dépenses publiques. Les résultats obtenus ici montrent que la corruption provoque des distorsions tendant d’une part, à accroître les allocations aux des dépenses publiques d’investissement, pour un effet induit non significatif sur la croissance économique, et d’autre part, à réduire la part des dépenses publiques de fonctionnement, pour un effet induit négatif sur la croissance économique. / Cameroon is an economy committed to an expansionist development strategy, yet faced with major economic growth challenges and chronic corruption. In this context. The purpose of this study is, therefore, to carry out a theoretical and empirical analysis of the effects of corruption on Cameroon's economic growth. The first analysis framework is aimed at determining the nature of causal relationship between corruption and economic growth in Cameroon. The estimations reveal that in long run, an increase in the level of corruption leads to a reduction in the rate of economic growth. This negative relationship is following a direct effect as well as indirect effects through private investment, education and public spending. The second axis of analysis seeks to assess the indirect effect of corruption on economic growth through distortions in the distribution of public expenditure. Our results show that corruption brings about distortions aimed at increasing allocations to public investment spending thereby producing an insignificant effect on economic growth on the one hand, and reducing the share of public recurrent expenditure with a negative effect on economic growth, on the other hand.

Background: Filtering is a ubiquitous step in the preprocessing of electroencephalographic (EEG) and magnetoencephalographic (MEG) data. Besides the intended effect of the attenuation of signal components considered as noise, filtering can also result in various unintended adverse filter effects (distortions such as smoothing) and filter artifacts. Method: We give some practical guidelines for the evaluation of filter responses (impulse and frequency response) and the selection of filter types (high-pass/low-pass/band-pass/band stop; finite/infinite impulse response, FIR/IIR) and filter parameters (cutoff frequencies, filter order and roll-off, ripple, delay and causality) to optimize signal to-noise ratio and avoid or reduce signal distortions for selected electrophysiological applications. Results: Various filter implementations in common electrophysiology software packages are introduced and discussed. Resulting filter responses are compared and evaluated. Conclusion: We present strategies for recognizing common adverse filter effects and filter artifacts and demonstrate them in practical examples. Best practices and recommendations for the selection and reporting of filter parameters, limitations, and alternatives to filtering are discussed.

Distorted thinking about food is common in both clinical and nonclinical populations from dieters to diabetics and eating disorder patients. This type of thinking is triggered by exposure to dieting culture (including related social media), familial dieting, and internalization of the thin ideal, among other factors. The consequences of distorted thinking about food include disordered eating, weight management problems, body dissatisfaction and many others. Despite these findings, distorted thinking about food in nonclinical samples remains poorly understood. Thus, the current research sought to investigate distorted thinking about food within a broad theoretical model that includes societal antecedents important to understanding the nature of this construct in the general population. This model, which is based on Cognitive Behaviour Therapy (CBT) and the Theory of Planned Behaviour (TPB; Ajzen, 1991), was investigated in two studies. The first study is a psychometric validation study of a tool designed to measure distorted thinking about food, the Calorie Catastrophizing Scale (CCS; Monaghan & Santor, 2017) as well as the tool designed to measure dietary misinformation, the Dietary Misinformation Questionnaire (DMQ; Monaghan & Santor, 2017). Results lend support for defining and measuring distorted thinking about food as a distinct construct in nonclinical individuals and suggest that dietary misinformation is an important antecedent to this type of thinking and unhealthy eating behaviours. The second study is a randomized controlled trial of a CBT- and TPB-based workshop intervention aimed at reducing these antecedents. Results show that this intervention led to a significant reduction in distorted thinking about food, dietary misinformation, and other important clinical variables such as symptoms of eating pathology. These findings have a number of important implications for how subclinical eating problems are conceptualized, measured, and prevented.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18795号 / 理博第4053号 / 新制||理||1583(附属図書館) / 31746 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 嶺重 慎, 教授 太田 耕司, 准教授 樽家 篤史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

No description available.

Scania has experienced difficulties with large variations of the slope of the back plane after press quenching of case hardened crown wheels of especially type R780 Steg supplied from ingot cast material. This leads to that a large number of crown wheels has to be remeasured and sorted according to back slope which is time consuming for operators. Also, after sorting of the crown wheels, hard machining has to be adjusted according to the different slopes of the back plane of the crown wheels. In some cases, it also leads to scrapping of the crown wheels.This master’s thesis was divided in two parts. The aim of the first part was to confirm that the crown wheel type and casting technique that exhibits the largest variations in slope of the back plane is the R780 Steg originating from ingot cast material. The crown wheel types that were compared were the R780 Steg, R780 Slät and R885 Slät. Crown wheels manufactured from ingot cast material and from continuous cast material were compared. Hence, 6 combinations were examined. The slope of the back plane was measured with the measuring probe FARO after press quenching. The slope of the crown wheels was found to depend on both casting technique and the geometry of the crown wheel. The results confirmed that the crown wheel type and supplier combination that by far yields the largest variations in slope of the back plane is the R780 Steg supplied by Steel Plant A who uses the ingot casting technique. For this combination the variation exceeds 0,1 mm. All other combinations of crown wheels and suppliers yield acceptable variations.The second part of this master’s thesis was composed of determining if segregations in the cast ingot are the cause of the variations in slope of the back plane of the crown wheel type R780 Steg. This was done by measuring if there is a correlation between the slope of the back plane of the crown wheel after press quenching, the chemical composition and the original position of the crown wheel in the ingot. As in the first part of the study, the distortion was measured by the measuring probe FARO. The samples were sent to Degerfors Laboratorium for chemical analysis. Analyses of C, S and N were made by using combustion analyses. For As, P, B and Al optic spectrometry (spark) was used. All other elements were analysed by x-ray fluorescence. Segregations were found to be present and in combination with the geometry of R780 Steg to be the cause of the large variations in slope of the crown wheels.The results of this thesis show that, for the crown wheel type R780 Steg, Scania should not use suppliers that employ the ingot casting technique. Instead, only suppliers using the continuous casting technique should be used. However, for the other crown wheel types ingot or continuously cast material can be used.