É muito importante para a indústria fornecer produtos competitivos e que exerçam corretamente as suas funções perante o cliente. Uma das ferramentas existentes para atingir estes objetivos é a realização de testes de fadiga e durabilidade cada vez mais refinados e em espaço mais curto de tempo. Uma das maneiras de se executar testes de fadiga mais precisos é utilizando parâmetros que sejam fiéis à solicitação que o produto sofre durante o seu uso. Com esse intuito surgiram os testes de fadiga sob amplitude variável. Juntamente com eles surgem as particularidades deste tipo de solicitação, que é de natureza complexa. Algumas particularidades são a dependência do resultado na história de carregamento (também chamada de \"interação de cargas\") e a variação abrupta do nível de carga durante o tempo de aplicação. Fenômenos estes chamados de sobrecarga ou subcarga (overload e underload), que aqui serão agrupados, muitas vezes de forma simplista, de perturbações no espectro de fadiga. A finalidade principal deste trabalho é descrever a influência das perturbações ocorridas nas solicitações nos testes de fadiga em regime de amplitude variável, mais precisamente em testes de bancada, em que se busca a reprodução de situações de trabalho reais de um componente. Apesar de esse assunto ser alvo de diversas investigações recentes, nenhum trabalho tem como foco a influência das paradas (completa remoção de carga) realizadas durante um teste de fadiga acelerado. Essas paradas são extremamente comuns na prática laboratorial, seja por manutenção do equipamento, inspeção da amostra ou necessidade de operação. O objeto alvo de estudo nesta pesquisa é um suporte metálico de buzina, utilizado em automóveis de passeio. Apesar de sua concepção simples, tal componente é responsável por exercer funções importantes e é sujeito a uma interessante gama de solicitações. Como resultado observou-se que a aplicação das paradas durante os testes de fadiga simulados no componente automotivo, provoca variações em sua vida útil total. E o tempo de parada também exerce influência nesta variação observada. Essas paradas não se encaixam perfeitamente nas classificações de perturbações no espectro registradas na literatura. Por esse motivo o trabalho se propõe ainda a sintetizar e uniformizar a terminologia para as variações abruptas de tensão aplicadas no tempo (as sobrecargas e as subcargas), tendo em vista que ocorre a falta de consenso entre os termos utilizados atualmente na literatura e seus respectivos conceitos. / It is very important to the industry to deliver competitive products that can properly perform their functions to the final customer. One existing tool for achieve this objective is the usage of abbreviated durability and fatigue tests. For more precise tests, the required parameters must be reliable when compared to the efforts that the component is submitted at the field during your real performance. In order to achieve these results, the fatigue tests under variable amplitude loading came to existence. Together came also in existence the singularities from this complex behavior. Some of these singularities are the dependence in loading history (also called \"load interaction effects\") and the abrupt load variation level during the test time. These phenomenons are called overloads or underloads. These particularities will be grouped in this work as \"perturbations\" on the fatigue spectrum. The main objective of this work is to describe the influence of these perturbations upon the fatigue tests under variable amplitude loading, more precisely on bench tests, where one seeks the concise reproduction of the real work situations for one component or system. Although this subject lately has caused more interest to the researchers, no work which focuses on the influence of the \"pauses\" (complete absence of load during the test) upon accelerated fatigue tests has been published yet until this moment. These pauses are extremely common due to equipment maintenance, test sample inspections or operational routines. The target of this work is a metallic horn bracket, which is used in light passenger vehicles. Although this is a simple component, it has important functions to perform and is subjected to a wide range of loads types. As result, there was been verified that the presence of the \"pause\" during the simulated fatigue tests causes changes in their total useful life. And the magnitude of the pause has your role too. Moreover, the pause do not properly fits into the current classifications for the perturbations on the fatigue specter that are today available on the literature. For theses reason, this work tries to resume and unify the terminology of the abrupt load variations during time (overloads and underloads) because there is some lack of consensus between the actual terminology and their concepts.

É muito importante para a indústria fornecer produtos competitivos e que exerçam corretamente as suas funções perante o cliente. Uma das ferramentas existentes para atingir estes objetivos é a realização de testes de fadiga e durabilidade cada vez mais refinados e em espaço mais curto de tempo. Uma das maneiras de se executar testes de fadiga mais precisos é utilizando parâmetros que sejam fiéis à solicitação que o produto sofre durante o seu uso. Com esse intuito surgiram os testes de fadiga sob amplitude variável. Juntamente com eles surgem as particularidades deste tipo de solicitação, que é de natureza complexa. Algumas particularidades são a dependência do resultado na história de carregamento (também chamada de \"interação de cargas\") e a variação abrupta do nível de carga durante o tempo de aplicação. Fenômenos estes chamados de sobrecarga ou subcarga (overload e underload), que aqui serão agrupados, muitas vezes de forma simplista, de perturbações no espectro de fadiga. A finalidade principal deste trabalho é descrever a influência das perturbações ocorridas nas solicitações nos testes de fadiga em regime de amplitude variável, mais precisamente em testes de bancada, em que se busca a reprodução de situações de trabalho reais de um componente. Apesar de esse assunto ser alvo de diversas investigações recentes, nenhum trabalho tem como foco a influência das paradas (completa remoção de carga) realizadas durante um teste de fadiga acelerado. Essas paradas são extremamente comuns na prática laboratorial, seja por manutenção do equipamento, inspeção da amostra ou necessidade de operação. O objeto alvo de estudo nesta pesquisa é um suporte metálico de buzina, utilizado em automóveis de passeio. Apesar de sua concepção simples, tal componente é responsável por exercer funções importantes e é sujeito a uma interessante gama de solicitações. Como resultado observou-se que a aplicação das paradas durante os testes de fadiga simulados no componente automotivo, provoca variações em sua vida útil total. E o tempo de parada também exerce influência nesta variação observada. Essas paradas não se encaixam perfeitamente nas classificações de perturbações no espectro registradas na literatura. Por esse motivo o trabalho se propõe ainda a sintetizar e uniformizar a terminologia para as variações abruptas de tensão aplicadas no tempo (as sobrecargas e as subcargas), tendo em vista que ocorre a falta de consenso entre os termos utilizados atualmente na literatura e seus respectivos conceitos. / It is very important to the industry to deliver competitive products that can properly perform their functions to the final customer. One existing tool for achieve this objective is the usage of abbreviated durability and fatigue tests. For more precise tests, the required parameters must be reliable when compared to the efforts that the component is submitted at the field during your real performance. In order to achieve these results, the fatigue tests under variable amplitude loading came to existence. Together came also in existence the singularities from this complex behavior. Some of these singularities are the dependence in loading history (also called \"load interaction effects\") and the abrupt load variation level during the test time. These phenomenons are called overloads or underloads. These particularities will be grouped in this work as \"perturbations\" on the fatigue spectrum. The main objective of this work is to describe the influence of these perturbations upon the fatigue tests under variable amplitude loading, more precisely on bench tests, where one seeks the concise reproduction of the real work situations for one component or system. Although this subject lately has caused more interest to the researchers, no work which focuses on the influence of the \"pauses\" (complete absence of load during the test) upon accelerated fatigue tests has been published yet until this moment. These pauses are extremely common due to equipment maintenance, test sample inspections or operational routines. The target of this work is a metallic horn bracket, which is used in light passenger vehicles. Although this is a simple component, it has important functions to perform and is subjected to a wide range of loads types. As result, there was been verified that the presence of the \"pause\" during the simulated fatigue tests causes changes in their total useful life. And the magnitude of the pause has your role too. Moreover, the pause do not properly fits into the current classifications for the perturbations on the fatigue specter that are today available on the literature. For theses reason, this work tries to resume and unify the terminology of the abrupt load variations during time (overloads and underloads) because there is some lack of consensus between the actual terminology and their concepts.

In this paper, we recover the amplitude of a seismic image by approximating the normal (demigrationmigration)operator. In this approximation, we make use of the property that curvelets remain invariant under the action of the normal operator. We propose a seismic amplitude recovery method that employs an eigenvalue like decomposition for the normal operator using curvelets as eigen-vectors. Subsequently, we propose an approximate non-linear singularity-preserving solution to the least-squares seismic imaging problem with sparseness in the curvelet domain and spatial continuity constraints. Our method is tested with a reverse-time ’wave-equation’ migration code simulating the acoustic wave equation on the SEG-AA salt model.

Dans le domaine aéronautique, la détection des défauts sur structures composites sefait lors des phases de maintenance. Celles-ci sont prévues de manière à détecter lesdéfauts avant que ceux-ci ne deviennent critiques pour la tenue des structures en service.L’optimisation des intervalles de maintenance représente donc un fort intérêt que ce soitau niveau financier ou opérationnel. Les dommages des structures composites sont aujourd’hui traités par la non-propagationdes défauts : lorsque ceux-ci apparaissent et qu’ils sont détectés, les pièces sont immédiatementréparées ou remplacées. Afin d’améliorer ces intervalles de maintenance, lecomportement des défauts soumis aux spectres de charges aéronautique nécessite d’êtrecaractérisé. Cela permettrait une transition vers une philosophie de tolérance aux dommages,en définissant des phases de propagation non-critique pour la tenue mécanique desstructures. Dans ce contexte, la propagation de délaminage est étudiée sous chargement de fatigue.En mode I de propagation, les effets de la fréquence de sollicitation et du rapport de chargesur la propagation de délaminage en fatigue sont déterminés. Ceux-ci amorcent l’étudede la propagation de délaminage sous spectre de charges à niveau variable. Les effets del’historique de chargement sont mis en évidence. En mode II de propagation, les effets de la fréquence de sollicitation sur la propagationde délaminage sont abordés pour quatre matériaux à l’aide d’un montage d’essaisvibratoires dédié. Une analyse thermique des essais est également conduite. De plus, leseffets du rapport de charge sont déterminés pour ce mode de propagation. / The detection of damage in composite aeronautical structures is carried out duringmaintenance phases. These operations are planned so that damage is detected beforereaching any critical size for the in-service structures. The optimization of maintenanceintervals is therefore of great interest both financially and operationally. Damage in composites structures is currently dealt through the no-growth approach :when damage appears and is detected, the affected parts are immediately repaired orreplaced. In order to improve the maintenance schedule, the behaviour of defects subjectedto aeronautical load spectra needs to be characterized. This would enable a transitiontowards a damage tolerance philosophy with a slow-growth approach by defining noncriticalpropagation phases for the mechanical strength of structures. In this context, delamination propagation under fatigue loading is studied. The effectsof loading frequency and load ratio on fatigue delamination propagation are determinedin mode I. Then a study of delamination propagation under complex load spectra isconducted for blocks at different loading amplitudes. Effects of the loading history arehighlighted. For the propagation in mode II, loading frequency effects on delamination propagationare investigated for four different composite materials using a dedicated vibration testingdevice. A thermal analysis is also conducted during high frequency tests. In addition, loadratio effects are determined for this propagation mode.

Submitted by DIEGO BELAPART null (diegobelapartt_@hotmail.com) on 2016-08-31T18:37:22Z No. of bitstreams: 1 Dissertação - Diego Belapart.pdf: 6487052 bytes, checksum: 06ab9c0d0c343df7b696c378464feec2 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-01T14:02:05Z (GMT) No. of bitstreams: 1 belapart_d_me_bot.pdf: 6487052 bytes, checksum: 06ab9c0d0c343df7b696c378464feec2 (MD5) / Made available in DSpace on 2016-09-01T14:02:05Z (GMT). No. of bitstreams: 1 belapart_d_me_bot.pdf: 6487052 bytes, checksum: 06ab9c0d0c343df7b696c378464feec2 (MD5) Previous issue date: 2016-07-08 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O atual sistema produtivo de cana-de-açúcar deixa quantidades variáveis de palhada na superfície do solo capaz de provocar supressão de algumas espécies de plantas daninhas, além de modificar as características químicas, físicas e biológicas dos solos. Portanto objetivou-se avaliar o efeito de diferentes quantidades de palha de cana-de-açúcar na emergência de plantas daninhas relevantes para a cultura da cana-de-açúcar, além de produzir informações necessárias para conduzir estudos complementares visando determinar a natureza dos efeitos observados. Para tanto, foram conduzidos três estudos de campo em três épocas distintas do ano avaliando-se os efeitos de diferentes quantidades da palha de cana-de-açúcar (0; 2,5; 5; 10; 15 e 20 t ha-1) sobre o regime térmico do solo em diferentes profundidades e sobre a emergência de nove espécies de plantas daninhas (Ipomoea grandifolia, Ipomoea nill, Ipomoea quamoclit, Brachiaria decumbens, Bidens pilosa, Euphorbia heterophylla, Panicum maximum, Ipomoea hederifolia e Merremia aegyptia) aos 7, 14, 21, 28, 35 e 42 dias após a semeadura (DAS). Os experimentos foram conduzidos em blocos casualizados com quatro repetições. A presença da palha sobre o solo alterou o regime térmico, reduzindo a amplitude térmica do solo, principalmente em menores profundidades. A palha reduziu a emergência de plantas daninhas e a intensidade do efeito é dependente da espécie e da quantidade do resíduo sobre o solo. A interferência da palha reduzindo a germinação de plantas daninhas foi pouco dependente da época do ano e das condições climáticas, sendo possível estabelecer modelos gerais relacionando a quantidade de palha com a porcentagem de emergência, quando a variável dependente foi expressa em porcentagem dos valores observados no tratamento sem palha. Houve grande variação nas quantidades de palha necessárias para reduzir em 50% a emergência das plantas daninhas. B. pilosa e P. maximum, espécies de sementes pequenas, foram as mais sensíveis aos efeitos da palha, enquanto que I. nil, I. hederifolia e M. aegyptia, com sementes maiores, foram as menos sensíveis. A palha de cana-de-açúcar sobre a superfície do solo influenciou na emergência das plantas daninhas. Os resultados indicaram que as dimensões e reservas das sementes são determinantes na definição da capacidade das plantas daninhas emergirem quando o solo está coberto por palha. / The sugarcane has great economic importance to the country. Even in the face of technological advances in the cultivation of sugarcane, interference from weeds still cause many losses. After the adoption of mechanized harvesting the weed management has become more complex, mainly due to varying amounts of straw left on the soil surface. In addition to the suppression effect by some weed species, the straw of sugarcane can also modify the chemical, physical and biological properties of soils. Therefore the aim of this study was to evaluate the effect of different amounts of straw sugarcane germination of weed relevant to the culture, as well as producing information necessary to conduct further studies in order to determine the nature of the effects observed . For that, we conducted three field studies that evaluated the effects of quantities of straw between 0 and 20 t ha-1 on the soil thermal regime and the emergence of nine species of weeds. Three experiments were conducted to the field at different times of the year. The experimental design was randomized blocks, with six treatments and four replications, totaling 24 installments. The treatments consisted of volumes of dry straw cane sugar (0, 2.5, 5, 10, 15 and 20 t ha-1). Each plot consisted of 4 m long and 3 m wide, totaling 12 m². In each were opened three trenches of 1 m2 and 5 cm deep, for sowing of approximately 100 seeds of nine species of weeds. In each trench was used three kinds, the first being Bidens pilosa, Ipomoea quamoclit and Merremia aegyptia; the second heterifolia Ipomoea, Ipomoea nil and B. decumbens and third, Panicum maximum, Ipomoea grandifolia and Euphorbia heterophylla. After sowing of the plants, the straw of sugarcane was evenly distributed as the volumes defined in the treatments. soil temperature assessments were carried out and the emergence of weeds at 7, 14, 21, 28, 35 and 42 days after sowing. The presence of straw on the soil changes the thermal regime, reducing the temperature range of the soil, especially at shallower depths. The straw reduced the emergence of weeds and the intensity of the effect is dependent on the kind and amount of residue on the ground. Interference of straw reducing the germination of weed was little dependent on the time of year and weather conditions, it is possible to establish general models relating the amount of straw with the emergence percentage, when the dependent variable was expressed as a percentage of the values observed in without straw treatment. There was wide variation in straw quantities required to reduce by 50% the emergence of weeds. Bidens pilosa Panicum maximum, small seed species were more sensitive to the effects of straw, while Ipomoea nil, Ipomoea hederifolia and Merremia aegyptia with larger seeds were less sensitive. The straw of sugarcane on soil surface influenced the emergence of weeds. The results indicated that the dimensions and reserves of seed are crucial in defining the capacity of emerging weeds when the soil is covered with straw.

L’électroencéphalogramme (EEG), mesure de l'activité électrique du cerveau, reste une des meilleures méthodes de prévision non-invasive des résultats neurologiques. L'objectif de notre travail est de développer un système de classification automatique qui prévoit des risques sur la maturation cérébrale, se traduisant par un état pathologique à 2 ans. Les caractéristiques du signal EEG, qui sont utiles à la prévision automatisée, sont traitées via un module appelée EEGDiag, et sont appliquées sur un ensemble de données issues de 397 dossiers de nouveau-nés prématurés. Chaque dossier comprend un enregistrement EEG, et un rapport concernant les informations et les diagnostics de l’enfant à la naissance et 2 ans plus tard (normal, pathologique ou douteux). Pour aider les médecins à prévenir l’état neurologique anormal du nouveau-né prématuré, nous avons développé plusieurs modèles de classification qui s’appliquent sur différentes séries de caractéristiques du signal EEG inspirées des annotations des neuropédiatres. Plusieurs modèles de classification et d’aide à la décision sont testés sur différentes extractions de la base de données afin de fournir aux médecins le système de classification le plus performant. Notre système proposé permet de détecter automatiquement des pronostics sur l’état pathologique du nouveau-né prématuré. Notre travail a consisté à subdiviser l’amplitude des bouffées du signal EEG en trois catégories : faible, moyenne et forte. Cette étude de subdivision a permis de choisir les intervalles associés à ces trois catégories permettant d’augmenter considérablement la performance de notre système de classification automatique. Une analyse de corrélation a permis de détecter des relations d’indépendance et de redondance entre certaines données, ce qui permet de réduire le nombre de variables décisives et de sélectionner ainsi la meilleure série de variables qui ramènent notre système à devenir optimal et plus efficace. Ces études nous ont permis d’atteindre un système de classification automatique basé sur une série de 17 variables avec une exactitude 93.2%. Ce système peut apporter une bonne sensibilité à la prévision de l’état neurologique du nouveau-né prématuré et peut servir comme aide à la décision dans le traitement clinique. / The electroencephalogram (EEG), a measure of the electrical activity of the brain, remains one of the best non-invasive methods for predicting neurological outcomes. The aim of our work is to develop an automatic classification system which predicts risks on cerebral maturation that can lead to a pathological condition at 2 years. The EEG signal characteristics, which are useful for automated prediction, are processed via an application called EEGDiag, and applied to a set of 397 records for premature infants. Each record include an EEG record and a report on infant information and diagnosis at birth and 2 years later (normal, sick or risky). To assist physicians in preventing any abnormal neurological condition of the premature newborn, we have developed several intelligent classification models which can be applied to several series of characteristics of the EEG inspired from the annotations of neuropediatricians. Several classification and decisional aid models have been tested on different extracted databases in order to offer to doctors the best efficient classification system. Our proposed system automatically detects the prognosis of the premature newborn pathological condition. Our work consisted of subdividing the amplitude of EEG signal burst into three categories: low, medium and high. This subdivision study allowed to choose Intervals of these three categories which have served to greatly increase the performance of our intelligent classification system. A correlative data analysis allowed to create an independence and redundancy relation between the data attributes, which reduces the number of decisive parameters and thus selects the best series of parameters that made our system optimal and more efficient. These studies enabled us to achieve a classification system based on a series of 17 parameters with an accuracy 93.2%. This system can provide good sensitivity on predicting the neurological status of premature newborn and can be used as a decisional aid in clinical treatment.

Dans ce projet de thèse, nous étudions le rôle joué par l'anomalie dû à la connexion composée dans les théories de supergravités dans l'espace-temps à huit dimensions. Ce genre d'anomalie est en effet engendrée par la structure quotient d'espace des champs moduli de la supergravité là où le nombre des super-charges posent des contraintes rigoureux. Notre accomplissement principal est de proposer des termes supplémentaires pour annuler cette anomalie dans la théorie de supergravité en huit dimensions avec seize supercharges. Ces termes, en outre, peuvent être considérés comme une manifestation des corrections provenant de la théorie de super-cordes et nous montrons par des calculs explicites qu'une amplitude sur une boucle dans la théorie de cordes correspondante reproduit ces termes. Motivés par cette démonstration de la cohérence entre la supergravité et la théorie de cordes, nous proposons un seuil mathématique pour la compactification de ces théories dans huit dimensions vers six dimensions sur une sphère en présence des branes de co-dimension 2. Ceci est une simulation de compactification sur une surface K3 à l'aide des branes. Nous montrons que la présence d'anomalie composé ne peut être justifiée que par des branes de co-dimensions deux. Nous discutons la dualité entre la théorie Heterotic et la théorie-F sous la lumière de 7-branes et puis la compactification des supergravités de dix dimensions sur K3 en présence des 5-branes. Tous cela nous ouvrent nouvelles voies pour étudier des aspects non-perturbatives de la théorie de cordes. Nous concluons avec un calcul sur deux boucles dans la théorie de cordes Heterotic de dix dimensions qui n'ont pas été beaucoup exploré dans la littérature. / We examine the structure of composite anomaly in maximal and half-maximal supergravity theories especially in eight space-time dimensions. The number of super-charges dictates the structure of the coset space of the moduli fields of the theory which in turn engenders the composite anomaly in such theories. Our main achievement lies in proposing counter-terms for such anomalies. These terms are of stringy nature and we show by explicit 1-loop amplitude calculations in corresponding string theories that those counter-terms are consistently provided by string amplitude. In the light of non-perturbative higher dimensional theories like F-theory, the anomaly cancelling counter-terms are seen to be related to co-dimension two branes e.g. 7-branes. We then use these results of 8-dimensional theories to provide for supergravity theories in six-dimensions by compactifying on a sphere in the presence of 5-branes. This is in fact a simulation of K3 compactification and our knowledge of composite connection provide us with threshold conditions to achieve such compactifications. All these analysis provide for greater insight into the non-perturbative regime of string theory. We then conclude with a calculation of 2-loop Heterotic string amplitude which has been very less explored in the literature.

[pt] Existe uma perspectiva crescente da utilização de alta tensão em corrente contínua (ATCC). Assim, com base em informações da literatura sobre ensaios elétricos em equipamentos para ATCC e em exigências quanto à confiabilidade de procedimentos metrológicos, nesta dissertação, propõe-se o monitoramento e análise de um parâmetro (ripple) de forma que se possa garantir a rastreabilidade de sistemas de medição de referência (SMR). Os SMRs permitem apenas uma análise quantitativa da tensão de calibração, sendo preciso avaliar e garantir que a incerteza não seja influenciada por ripples de até 3 por cento, mas torna-se necessário também fazer uma avaliação qualitativa. No caso de ensaios em ATCC, o uso de diferentes fontes e retificadores provoca ripple em diferentes níveis, influenciando na qualidade da tensão fornecida e possivelmente em outros parâmetros relevantes descritos na norma ABNT NBR IEC 60060-1:2013. Nesse contexto, o objetivo desta dissertação foi o aperfeiçoamento e validação, com o rascunho da norma IEC 61083-4, de um algoritmo de medição previamente desenvolvido em LabVIEW que se comunique com um multímetro de 8 (1 sobre 2) dígitos e estime todos os parâmetros normalizados. Estabeleceu-se, ainda, os procedimentos necessários para calibração em ATCC e a análise da influência do ripple a partir dos parâmetros definidos pela norma. Para validar a metodologia proposta nesta dissertação foram feitos ensaios com diferentes arranjos, cuja finalidade foi comparar, estatisticamente, as incertezas de medição da calibração com diferentes níveis de ripple no SMR. Finalmente, os resultados obtidos indicam que o ripple não influencia na calibração. / [en] There is a growing prospect of using high voltage in direct current (HVDC). Thus, based on information from the literature on dielectric tests in equipment for HVDC and requirements regarding the reliability of metrological procedures, this dissertation aims at monitoring and analyzing a specific parameter (ripple) in a way that can guarantee the traceability of reference systems. The reference systems allow only a quantitative analysis of the calibration voltage, being necessary to evaluate and ensure that the measurement uncertainty is not influenced by ripples of up to 3 percent, but it is also necessary to make a qualitative assessment. In the case of HVDC tests, the use of different power supplies and rectifiers causes ripple at different levels, influencing the quality of the supplied voltage and possibly other relevant parameters for the ABNT NBR IEC 60060-1:2013 standard. In this context, the objective of this dissertation was the improvement and validation, with the draft of the IEC 61083-4 standard, of a signal acquisition and processing algorithm developed in LabVIEW that communicates with an 8 (1 over 2) digit multimeter and estimates all the normalized parameters. It is also intended to establish the procedures introduced for HVDC calibration and an analysis of the ripple influence from the parameters defined by the standard. To validate the methodology proposed in this dissertation, tests were made with different arrangements, with universal and purely resistive dividers, and different ripple levels, in the laboratory, statistically comparing the calibration measurement uncertainties with different ripple levels in the traceability of reference systems. Finally, the results indicate that the ripple does not influence the calibration.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper considers the use of Amplitude-Phase Shift Keying (APSK) for a telemetry system. Variable rate turbo codes are used to improve the power efficiency of 16- and 32-APSK. We discuss compensation techniques for power amplifier nonlinearities. Simulation results show the improved spectral efficiency of this modulation scheme over those currently defined in telemetry standards.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / An algorithm for automatic modulation recognition of ASK, PSK and FSK was developed by Azzouz and Nandi. The algorithm has some serious problems at SNR of 10 dB and below. This paper describes a modification to the algorithm that significantly improves the performance for detection of ASK and FSK at moderate and low SNR.