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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.
421

XIV. Internationales Oberflächenkolloquium / XIV. International Colloquium on Surfaces - Proceedings

08 February 2017 (has links) (PDF)
Zentrales Thema des Oberflächenkolloquiums 2017 ist die anwendungsorientierte, funktionale geometrische Spezifikation und Messung der Oberfläche im Sinne der Gesamtgeometrie. Neben der Mikrogestalt wird dabei das Zusammenwirken mit der Makrogeometrie zur Erfüllung funktionaler Anforderungen diskutiert. Interessante Beiträge aus Industrie und Wissenschaft zeigen sowohl Lösungen als auch Probleme verschiedenster Fachbereiche auf. / Key issue of the International Colloquium on Surfaces 2017 is the application‐oriented, functional geometrical specification and verification of surfaces as part of the entire geometry. Therefore we discuss the interaction of micro and macro geometry, to fulfill functional requirements. Interesting articles from industry and research point out solutions as well as problems from multifaceted fields of expertise.
422

The place of lead in an Egyptian port city in the Late Period

van der Wilt, Elsbeth M. January 2013 (has links)
This thesis analyses a range of lead objects discovered in Thonis-Heracleion, an Egyptian port city, and offers a new perspective on the use of metals in antiquity. It advances two central arguments: firstly, that the large quantity of lead artefacts in Thonis-Heracleion is not exceptional but rather a more accurate reflection of the metallisation of ancient societies and secondly, that the corpus of lead objects sheds light on aspects of ancient communities that normally remain invisible due to the ease of recycling and low cost of lead. The first chapter reviews the presence of lead in the archaeological record in Egypt, the factors affecting its deposition and preservation, and the corpus as a whole from Thonis-Heracleion. A comparison between the two puts the lead from the site in a new Egyptian perspective. The second, third, and fourth chapters offer substantial analyses of lead ingots, weights, and containers found at Thonis-Heracleion with parallels from around the Mediterranean. The chapters show the potential of this corpus to shed light on activities in the Egyptian town despite the notable lack of direct parallels. It becomes clear for example that large lead objects appear earlier in the archaeological record and that the range of objects is wider than previously suspected. The analysis in these chapters offers a robust dating framework for lead objects previously unavailable. Together the lead artefacts illustrate local mercantile activities, the economic role of the port city, and, through the identification of the first Athenian weights found in Egypt, trade connections between Egypt, Athens, and the rest of the Eastern Mediterranean. The result is an overview of lead in Egypt and its place in Thonis- Heracleion, demonstrating the significance of metals for understanding ancient societies.
423

La cohérence conceptuelle d’étudiants collégiaux en mécanique newtonienne et en métrologie

Périard, Martin 12 1900 (has links)
Cette thèse porte sur l’évaluation de la cohérence du réseau conceptuel démontré par des étudiants de niveau collégial inscrits en sciences de la nature. L’évaluation de cette cohérence s’est basée sur l’analyse des tableaux de Burt issus des réponses à des questionnaires à choix multiples, sur l’étude détaillée des indices de discrimination spécifique qui seront décrits plus en détail dans le corps de l’ouvrage et sur l’analyse de séquences vidéos d’étudiants effectuant une expérimentation en contexte réel. Au terme de ce projet, quatre grands axes de recherche ont été exploré. 1) Quelle est la cohérence conceptuelle démontrée en physique newtonienne ? 2) Est-ce que la maîtrise du calcul d’incertitude est corrélée au développement de la pensée logique ou à la maîtrise des mathématiques ? 3) Quelle est la cohérence conceptuelle démontrée dans la quantification de l’incertitude expérimentale ? 4) Quelles sont les procédures concrètement mise en place par des étudiants pour quantifier l’incertitude expérimentale dans un contexte de laboratoire semi-dirigé ? Les principales conclusions qui ressortent pour chacun des axes peuvent se formuler ainsi. 1) Les conceptions erronées les plus répandues ne sont pas solidement ancrées dans un réseau conceptuel rigide. Par exemple, un étudiant réussissant une question sur la troisième loi de Newton (sujet le moins bien réussi du Force Concept Inventory) montre une probabilité à peine supérieure de réussir une autre question sur ce même sujet que les autres participants. De nombreux couples de questions révèlent un indice de discrimination spécifique négatif indiquant une faible cohérence conceptuelle en prétest et une cohérence conceptuelle légèrement améliorée en post-test. 2) Si une petite proportion des étudiants ont montré des carences marquées pour les questions reliées au contrôle des variables et à celles traitant de la relation entre la forme graphique de données expérimentales et un modèle mathématique, la majorité des étudiants peuvent être considérés comme maîtrisant adéquatement ces deux sujets. Toutefois, presque tous les étudiants démontrent une absence de maîtrise des principes sous-jacent à la quantification de l’incertitude expérimentale et de la propagation des incertitudes (ci-après appelé métrologie). Aucune corrélation statistiquement significative n’a été observée entre ces trois domaines, laissant entendre qu’il s’agit d’habiletés cognitives largement indépendantes. Le tableau de Burt a pu mettre en lumière une plus grande cohérence conceptuelle entre les questions de contrôle des variables que n’aurait pu le laisser supposer la matrice des coefficients de corrélation de Pearson. En métrologie, des questions équivalentes n’ont pas fait ressortir une cohérence conceptuelle clairement démontrée. 3) L’analyse d’un questionnaire entièrement dédié à la métrologie laisse entrevoir des conceptions erronées issues des apprentissages effectués dans les cours antérieurs (obstacles didactiques), des conceptions erronées basées sur des modèles intuitifs et une absence de compréhension globale des concepts métrologiques bien que certains concepts paraissent en voie d’acquisition. 4) Lorsque les étudiants sont laissés à eux-mêmes, les mêmes difficultés identifiées par l’analyse du questionnaire du point 3) reviennent ce qui corrobore les résultats obtenus. Cependant, nous avons pu observer d’autres comportements reliés à la mesure en laboratoire qui n’auraient pas pu être évalués par le questionnaire à choix multiples. Des entretiens d’explicitations tenus immédiatement après chaque séance ont permis aux participants de détailler certains aspects de leur méthodologie métrologique, notamment, l’emploi de procédures de répétitions de mesures expérimentales, leurs stratégies pour quantifier l’incertitude et les raisons sous-tendant l’estimation numérique des incertitudes de lecture. L’emploi des algorithmes de propagation des incertitudes a été adéquat dans l’ensemble. De nombreuses conceptions erronées en métrologie semblent résister fortement à l’apprentissage. Notons, entre autres, l’assignation de la résolution d’un appareil de mesure à affichage numérique comme valeur de l’incertitude et l’absence de procédures d’empilement pour diminuer l’incertitude. La conception que la précision d’une valeur numérique ne peut être inférieure à la tolérance d’un appareil semble fermement ancrée. / This thesis evaluates the coherence of the conceptual network demonstrated by college students in life and applied sciences. This evaluation was based on the analysis of Burt tables issuing from multiple choice questionnaires, on the creation and careful examination of a novel tool, the matrix of specific discrimination coefficients, which will be described in the main text, and on the qualitative analysis of actual laboratory work of students doing an experimentation. At the completion of this project, four research axis have been explored. 1) What is the conceptual coherence demonstrated in Newtonian mechanics? 2) Is the mastery of uncertainty quantification related to the development of logical thinking or to mathematical competency? 3) What is the conceptual coherence demonstrated in the quantification of experimental uncertainty? 4) What are the concrete procedures utilized by students to quantify experimental uncertainty in a semi-directed laboratory context? The main conclusions that emerged from each axis of research can be summerized as follow. 1) The most prevalent erroneous conceptions are not solidly set in a rigid conceptual network. For example, a student successful in a question about Newton’s third law (the most difficult subject of the Force Concept Inventory) is just slightly more likely to succeed in another related question than the other participants. Many pairs of questions displays a negative specific discrimination coefficient demonstrating a weak conceptual coherence in pre-test and a somewhat ameliorated conceptual coherence in post-test. 2) If a small proportion of students has demonstrated marked deficiencies in questions related with control of variable and in those related to the relationship between the graphical display of experimental data and a mathematical model, the majority of students can be considered as adequately mastering those subjects. However, almost every student demonstrated a lack of mastery of concepts underlying the quantification of experimental uncertainty and the propagation of uncertainty (heretofore referred to as metrology). No statistically significant correlation has been observed between the three main topics suggesting that they are largely independent cognitive abilities. Burt table has demonstrated a greater degree of conceptual coherence between control of variables questions than suggested by Pearson correlation coefficients. Equivalent question in the topic of metrology did not permit to demonstrate a clear conceptual coherence. 3) Analysis of a questionnaire entirely devoted to metrology has shown erroneous conceptions caused by prior learning (didactical obstacles), erroneous conceptions based on intuitive models and a lack of global comprehension of metrological concepts although some appear to be almost acquired. 4) When doing real experiments in semi-directed laboratory, students demonstrated the same difficulty identified in the questionnaire of 3) which could interpreted as corroborating previously obtaine results. However, many unanticipated behaviors related to measurement were observed that could not have been anticipated solely by analyzing answers in the multiple-choice questionnaire. Interviews immediately following each semi-directed laboratory permitted the participants to detail certain aspects of their metrological methodology. Most notably, the use of repeated measurement strategies, their « spontaneous » strategies to quantify uncertainty, and their explanation of numerical estimates of reading uncertainties. Overall, uncertainty propagation algorithms were adequately employed. Many erroneous metrological conceptions seem to resist strongly to be modified by learning. Among others, assignation of the resolution of a digital scale as the uncertainty value and the lack of stacking strategies to diminish uncertainty. The conception that a numerical value cannot be more precise than the tolerance of an instrument seems firmly set.
424

Filtre mosaïque hyperspectral / Hyperspectral mosaic filter

Sorce, Stéphane 20 December 2012 (has links)
L'utilisation de filtre mosaïque hyperspectral semble être la solution idéale pour alléger les imageurs spectraux utilisés lors des missions spatiales. Les contraintes liées à ce type d'utilisation imposent l'emploi de filtres interférentiels multicouches. Ces travaux ont pour but de trouver des solutions pour réaliser un filtre mosaïque hyperspectral avec des filtres interférentiels et non avec les résines colorées traditionnellement utilisées. Pour ce faire une étude théorique sur la simplification des designs des empilements interférentiels a été effectuée. Il en ressort que les empilements restent épais, ce qui complique leur structuration. Plusieurs méthodes de structurations ont été étudiées. En particulier le lift-off qui est la technique actuellement utilisé aujourd'hui et le lift-up. Cette dernière présente l'avantage de ne pas mettre en série le risque technologique associé à chaque réalisation de filtre. Un trade-off entre ces deux techniques a été fait ainsi que des réalisations expérimentales. Celles-ci ont ensuite été caractérisées par un banc de mesure développé dans ce but qui a permis de valider expérimentalement la technique utilisée. / Hyperspectral mosaic filter appears to be the perfect solution to lighten the spectral imagers used in space missions. Such applications require the use of multilayer interference filters. This work aims to find solutions to achieve hyperspectral mosaic filter with interference filters rather than the conventionally used coloured resins. In order to achieve this, a theoretical study on the simplification of multilayer designs was performed. It appears that the stacks are thicker, which makes them difficult to pattern. Several methods of patterning were studied, especially the lift-off technique which is traditionally used and the lift-up. The latter has the advantage to avoid adding the technological risk associated with each filter production. A trade-off between these two techniques was done as well as experimental productions. These were then characterized by a bench developed for this purpose which has experimentally validate the technique used.
425

Etude et développement d'une mesure pyrométrique en cœur de réacteur pour le suivi de la température d'une gaine de combustible : application à l'étude des accidents de perte de réfrigérant primaire (APRP) au cours d'essais de simulation dans le réacteur expérimental Jules Horowitz. / Study and development of a nuclear in core pyrometry measure for a fuel rod temperature tracking : application to Loss of Coolant Accident (LOCA) in simulating tests for the Materials Testings Reactor Jules Horowitz.

Ramiandrisoa, Liana 01 July 2014 (has links)
Dans l'industrie comme dans la Recherche, la température est un paramètre clef pour la maîtrise et la compréhension du comportement des matériaux. Ainsi, dans le Réacteur nucléaire de Recherche Jules Horowitz (RJH), actuellement en construction au CEA Cadarache, un dispositif expérimental est élaboré afin d'étudier le comportement thermomécanique d'une gaine combustible. Celle-ci sera placée dans des conditions qui simulent une situation accidentelle (Accident de Perte de Réfrigérant Primaire, APRP) pendant laquelle elle s'échauffera rapidement. Le suivi de température, entre 700 et 1200 à ±10°C, doit pouvoir se faire par un capteur pyrométrique déporté par fibre optique. L'enjeu est d'optimiser la mesure en comparant différentes techniques de pyrométrie. Pour cela, l'étude est menée sous l'angle des deux principales difficultés techniques inhérentes à la réalisation du capteur. Le premier défi est lié au comportement des fibres optiques dans un environnement mixte où irradiation et haute température sont intimement liées. La fibre va subir des flux neutroniques de l'ordre de 10^12 nrapide/cm²/s et un débit de dose d'environ 1kGy/s. De plus son extrémité est soumise à une température de paroi élevée, de l'ordre de 800°C. Dans ces conditions, lumières parasites, bandes d'absorption et atténuation fluctuante sont autant de contraintes dont les effets sont à éviter ou à minimiser. Une étude prédictive fait le point sur les recommandations théoriques à suivre pour une mesure optimale.La seconde difficulté, qui concerne la mesure de température par pyrométrie, vient des variations spectrales attendues pour l'émissivité de la cible. Le matériau d'étude, choisi pour son utilisation dominante en France, est le Zircaloy-4. Sous l'effet de l'oxydation, l'émissivité spectrale de cet alliage de Zirconium évolue. Ce manuscrit montre qu'entre 700 et 800°C il est expérimentalement possible d'effectuer une mesure pyrométrique en laboratoire, hors irradiation.En croisant ces différents résultats, il apparaît envisageable d'effectuer une mesure de température dans les conditions du RJH à condition de maîtriser les différents paramètres parasites et de privilégier certaines longueurs d'onde. Ce travail s'inscrit dans une voie prometteuse pour l'utilisation à distance de la pyrométrie optique en milieu nucléaire civil sévère. / In both research and industry, temperature is a key parameter for understanding and characterizing the behavior of materials. To study the thermomechanical behavior of a fuel rod, a test device is designed for the Jules Horowitz Material Testing Reactor (currently under construction in the CEA Cadarache). The device will be placed under accidental conditions (Loss Of Coolant Accident, LOCA) causing rapid overheating. The temperature tracking, between 700 and 1200°C, will be measured by a fiber optic sensor. The aim of the project is to optimize temperature measurement by comparing different pyrometry techniques. This study covers the management of the main difficulties inherent to the design of the sensor.The first challenge consists of predicting optical fiber behavior in such complex environments where irradiation and high temperature are combined. The fiber will be exposed to a neutron dose rate about 10^12 nfast/cm²/s and ϒ dose rate of about 1kGy/s. Moreover its extremity is heated to approximately 800°C. It is shown that under these conditions, light interferences, absorption bands and fluctuating attenuation are obstacles to overcome or to mitigate.The second challenge, concerning pyrometric measurement, comes from spectral variations expected for the rod emissivity. The material of study is chosen for its widespread use in France: Zircaloy-4. Under oxidating conditions the spectral emissivity of this Zirconium alloy evolves. This thesis proves that between 700 and 800°C pyrometric measurement is possible from experimental point of view in laboratory without irradiation.In conclusion rod temperature tracking in JHR conditions may be possible providing that interferences are mastered and wavelengths are chosen. This work makes the use of optical pyrometry under civil nuclear extreme conditions more promising.
426

[en] CALIBRATING THE ELECTRICAL APPLIANCES ONWERSHIP SURVEYS THROUGH ELECTRONICS DEVICES MEASUREMENTS OF ENDUSES CONSUMPTION / [pt] CALIBRAÇÃO DE RESULTADOS DE PESQUISAS DE POSSES E HÁBITOS PELA MEDIÇÃO ELETRÔNICA DE CONSUMO DE ELETRODOMÉSTICOS

JOSE AGUINALDO MENDES PINHO 03 September 2013 (has links)
[pt] Nesta dissertação, é apresentado um procedimento estatístico para a estimação de perfis de curvas de carga por aparelhos para consumidores residenciais atendidos na BT (Baixa Tensão). O modelo desenvolvido utiliza informações de duas fontes distintas: PPHs (Pesquisas de Posses e Hábitos de Aparelhos Elétricos) e Medições de consumo com medidores eletrônicos com memória de massa que gravam leituras de consumo por aparelhos a cada 15 minutos. Através das PPHs desenvolvidas por Procel/Eletrobrás em 1996, obtêm-se um perfil aproximado da curva de carga do domicilio por aparelho. Entretanto, esta curva tende a ser imprecisa, pois é obtida por declarações de uso dos aparelhos. Para reduzir esta imprecisão, foi montado um experimento onde uma sub-amostra de domicílios auditados pelas PPHs, teve os principais aparelhos da residência medidos por medidores eletrônicos em intervalos de 15 minutos. A partir das curvas de utilização destes aparelhos, obtidas pelos dois procedimentos, utilizou-se um modelo estatístico de regressão linear para estimar coeficientes de ajustes para correção das curvas declaradas para cada hora do dia, para os principais eletrodomésticos do domicílio. Os resultados foram aplicados a duas distribuidoras do grupo ENDESA: AMPLA e COELCE. / [en] In this thesis, it is presented a statistical based model that allows the estimation of the load shape curve for appliances (end uses) for residential consumers that belong to low voltage group (BT clients), using information from two sources: PPHs (Energy Audit on Ownership and Usage of Electrical Appliances) and household measurements through specific devices that provide not only the total consumption (15 minute intervals) as well as the breakdown of this consumption for each device (end use) existing in the household. Through energy audits (PPHs) developed by Procel/Eletrobrás in 1996, one has a rough idea of the load shape curves by appliance. However, the curves obtained this way tend to be rather imprecise, as they are obtained by the consumer information of usage of the equipments on the surveys, which tend to be rather vague. In order to reduce such imprecision, an experiment was set where a subsample of the original survey sample is selected and the main appliances consumption measured by electronic meters at intervals of 15 minutes. The end use load shape obtained by these meters are then compared with the corresponding curve obtained by usage declaration. Using the linear regression model, the correction coefficients of the declarations are obtained for each hour of the day, for the main appliances. The results were applied to two distribution utilities of the ENDESA group: AMPLA and COELCE.
427

[en] METROLOGICAL RELIABILITY OF THE DYNAMOMETRIC BENCH FOR ENGINE TESTING OF CTEX / [pt] CONFIABILIDADE METROLÓGICA DO BANCO DINAMOMÉTRICO PARA ENSAIO DE MOTORES DO CTEX

SERGIO BRAGANTINE GERMANO 16 July 2014 (has links)
[pt] Nesta dissertação buscou-se avaliar metrologicamente um banco de ensaios dinamométricos específico, utilizado para analisar a eficiência de motores, lubrificantes e combustíveis, por meio de métodos de comparação dos valores medidos com valores padrões. As grandezas mensuradas foram: velocidade de rotação do eixo de um motor, torque neste eixo, temperaturas e pressões no motor e no dinamômetro, elemento que atua como freio do motor para proporcionar uma simulação das condições reais de trabalho. Foi necessário utilizar dois métodos distintos para avaliação de cada uma das grandezas mensuradas. Foram mensuradas velocidades do motor funcionando e velocidades simuladas, tanto inferiores como superiores às velocidades de operação do motor, determinando os limites superior e inferior de resposta do sistema de medição. Para avaliar a medição de torque, foram produzidos torques conhecidos (padrão), correlacionados com torques medidos no motor funcionando. Temperaturas foram produzidas por um banho termostático, mensuradas com equipamentos calibrados e em seguida comparadas com as indicadas pelo sistema de medição, sendo também utilizado um método simulador de informações de temperaturas, chegando a ser simuladas de -200 graus Celsius a 650 graus Celsius. Pressões foram geradas por uma bomba de pressão padrão e lidas pelo sistema de medição, sendo detectado funcionamento inapropriado de 2 canais. Os resultados de cada grandeza foram tratados estatisticamente sendo validadas suas utilizações nos cálculos executados. Confirmadas estatisticamente as validades dos resultados, as incertezas de medição foram calculadas, sendo utilizadas também informações dos certificados de calibração dos equipamentos usados nas medições realizadas. Sugestões foram apresentadas para que melhoria sejam incrementadas ao sistema de medição que demonstrou estar funcionando de forma satisfatória, apresentando, no entanto, algumas oportunidades de melhorias. / [en] This work intended to evaluate, metrologically, a specific bench of dynamometric tests, used to analyze the efficiency of engines, lubricants and fuels, through methods that compare the measured values with standards. The measured quantities were: rotation speed of the engine shaft, torque on this same shaft, temperature and pressure of both engine and dynamometer, element that acts as the engine brake so it can simulate a real work condition. It was necessary to use two different methods to evaluate each measured quantity. It was measured the working engine speed and simulated speeds, both higher and lower than the engine operating speeds, establishing the higher and the lower limits of the measurement system. To evaluate the torque measurement, known torques (standards), were produced, and related to the measured torques in the working engine. Temperatures were produced by a thermal bath, measured with calibrated equipment, and then compared with the temperatures indicated by the measuring system, being also used a simulated method for temperatures information, with a range of simulation between -200 Celsius degrees and 650 Celsius degrees. The pressures were created by a standard pressure pump and read by the measuring system, being detected an inappropriate operation of 2 channels. The results were treated statistically, being validated the utilizations on the executed calculations. Having been statistically confirmed the validity of the results, the measurement uncertainties were calculated, being also used the information from the equipment calibration certificate. Suggestions were presented so that improvemenst can be made to the Measuring System.
428

[en] REMOTE MEASUREMENT AS STRATEGY TO MONITOR STATIONARY BATTERIES: CASE STUDY IN AN ELETRIC POWER SUBSTATION / [pt] MEDIÇÃO REMOTA COMO ESTRATÉGIA DE MONITORAMENTO DE BATERIAS ESTACIONÁRIAS: ESTUDO DE CASO EM UMA SUBESTAÇÃO DE ENERGIA ELÉTRICA

GILCINEA RANGEL PESENTI 01 October 2013 (has links)
[pt] A presente dissertação tem por objetivo geral validar em condições reais de operação, a técnica (desenvolvida em ambiente laboratorial) de monitoramento remoto de baterias estacionárias e como objetivos específicos identificar as limitações das tecnologias convencionais de monitoramento de baterias estacionárias, avaliar a confiabilidade do método de monitoramento remoto proposto e justificar a alternativa tecnológica proposta à luz do impacto econômico que dela decorrem. O desenvolvimento deste tema de dissertação de mestrado foi motivado pelas contribuições que poderá produzir para a Light e demais empresas dos setores elétricos, óleo e gás, bancário, de telecomunicações, entre outros setores que utilizam baterias estacionárias. A Light e o CPqD realizaram o projeto de PeD Light-Aneel 033/2008. Este projeto teve como objetivo o aumento da confiabilidade dos serviços auxiliares das subestações e redução dos custos de manutenção. Para tal efeito, foi desenvolvido um sistema automatizado de monitoramento e gestão individual e remota de todos os elementos que compõe o banco de baterias. A pesquisa de mestrado avaliou, quantitativamente, a confiabilidade da medição remota realizada na subestação Baependi da Light, na cidade do Rio de Janeiro. A metodologia aplicada na presente dissertação consiste em estudos estatísticos (Testes de hipóteses paramétricos e não paramétricos) para comparação de resultados de tensão elétrica e impedância obtidos em condições reais de operação (Medições SIMBA-GEBAT) em relação ao equipamento portátil de medição. A pesquisa validou aos níveis de significância de 90 por cento, 95 por cento e 99 por cento, a metodologia empregada para avaliação remota de baterias para os ensaios de impedância e tensão elétrica e identificou a repetitividade da metodologia da avaliação remota. O resultado da pesquisa foi fundamental para provar a credibilidade do sistema de monitoramento remoto de baterias. A utilização desse sistema ora validado contribuirá para o aumento da confiabilidade dos equipamentos que utilizam sistema de backup, além de redução dos custos de manutenção preventiva. / [en] The present work has the general objective of validating, under real operation conditions, the technique (developed in a laboratorial environment) of remote monitoring of stationery batteries. The development of this MsC dissertation theme was motivated by the contributions that it is expected to give to the Light S.E.S.A. and other companies of the Electric Sector, Oil and Gas, Bank, IT and many others which use stationary batteries in their DC energy supply. Light and CPqD developed together a Research and Development Project named ReD Light-ANEEL 033/2008. This project had as its main objective to increase the reliability of the ancillary services of substations and to reduce their maintenance costs. To reach this target, was developed an automated monitoring system and a remote individual management of all elements that form the batteries bank. The MSc research evaluated, quantitatively, the reliability of the remote metering, performed to the Light’s Baependi substation, which is located in the south zone of Rio de Janeiro City. The methodology applied in this dissertation consists of statistical studies (Hypothesis testing parametric and nonparametric), for comparison of voltage and impedance results obtained in actual operating conditions (Measurements SIMBA-GEBAT) compared to portable measurement. The research has validated, to the significance levels of 90 per cent, 95 per cent and 99 per cent, the methodology used to the remote evaluation of batteries relatively to the impedance and voltage essays, and has also identified the repetitivity of the remote evaluation methodology. The research results were fundamental to prove the credibility of the remote monitoring system of batteries. The use of this system will contribute to increase the reliability of the equipments which use backup systems, besides promoting a cost reduction of the predictive maintenance.
429

[en] DEVELOPMENT AND METROLOGICAL VALIDATION OF A HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC METHOD FOR THE QUANTIFICATION OF CYCLOFENIL AFTER PHOTOCHEMICAL DERIVATIZATION / [pt] DESENVOLVIMENTO E VALIDAÇÃO METROLÓGICA DE MÉTODO ANALÍTICO POR CROMATOGRAFIA LÍQUIDA DE ALTA EFICIÊNCIA PARA A QUANTIFICAÇÃO DE CICLOFENIL APÓS DERIVAÇÃO FOTOQUÍMICA

JUAN JOSE GARCIA ANTONIO 22 October 2013 (has links)
[pt] O ciclofenil é um medicamento antiestrogênico usado em tratamentos de distúrbios ovarianos. Por outro lado, esse efeito em homens resulta em aumento de massa muscular, sendo seu uso proibido para atletas do sexo masculino pelo código mundial antidoping estabelecido pela WADA. Os métodos de espectrofotometria de absorção e de fluorescência permitem quantificar direta ou indiretamente o ciclofenil, porém não são adequados para a análise de amostras mais complexas. Este trabalho propõe o desenvolvimento de um método baseado na cromatografia líquida de alta eficiência para determinação de ciclofenil usando detecção por fluorescência, após a fotoderivação do ciclofenil. A separação utiliza eluição isocrática (tampão borato 10 mmol/L(-1), pH 10/metanol/ 60/40 por cento v/v), e coluna C18 mantida a 35 graus Celsius. Após a fotoderivação com UV, formaram-se fotoderivados luminecentes, como previsto na literatura, sendo que o fotoderiado com tempo de retenção igual a 2,7 min foi o escolhido para fins quantitativos por ser estável ao longo de 96 h após o processo de derivatização. Foram obtidos os limites de detecção de 6,6 x 10(-8) mol/L(-1) e de quantificação de 7,3 x 10(-7) mol/L(-1). A faixa de resposta linear se extendeu até 5 x 10(-5) mol/L(-1) (de ciclofenil). As recuperações obtidas em formulações farmacêuticas se apresentaram entre 94 e 105 por cento. Os resultados indicaram que a homogeneidade e estabilidade dos medicamentos de ciclofenil são satisfatórias. As fontes que mais contribuiram para a incerteza de medição estão associadas ao preparo das soluções e à construção da curva analítica. / [en] Cyclofenil is an anti-estrogen used in treatments of ovarian disorders. On the other hand, its effect in men results in the increasing of muscle mass, being its use, by male athletes, banned by the World Anti-Doping Code established by World Anti-Doping Agency. Absorption and fluorescence spectrophotometries allow direct or indirect quantification of cyclofenil, however, they are not suitable for the analysis of complex samples. This work proposes the development of a method based on high performance liquid chromatography to determine cyclofenil using photochemical induced fluorescence detection. The separation using isocratic elution (10 mmol/L(-1) borate buffer at pH 10/methanol (60/40 per cent v/v), and column C18 maintained at 35 degrees celsius. After exposing cyclofenil to the UV, fluorescent photoderivatives were formed, as indicated in the literature, with the photoderivative with the retention time of 2.7 min used for quantitative purposes since it is stable for over 96 h after the photoderivatization procedure. The detection limit was 6.6 x 10(-8) mol/L(-1) and the limit of quantification was 7.3 x 10(-7) mol/L(-1). The linear response range extended up to 5 x 10(-5) mol/L(-1) (as cyclofenil). Recoveries in pharmaceutical formulations were between 94 and 105 per cent. The results indicated that the homogeneity and stability of cyclofenil tablets are satisfactory. The uncertainty sources that present the greatest contributions to the measurement uncertainty were the ones associated with the preparation of the solutions and the analytical curve.
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[en] CRITICAL ANALYSIS OF PACKAGED ORGANIC FOOD LABELS / [pt] ANÁLISE CRÍTICA DOS RÓTULOS DE ALIMENTOS ORGÂNICOS EMBALADOS

CAMILA DA SILVA CONCEICAO 19 May 2014 (has links)
[pt] O Brasil encontra-se entre os maiores produtores de orgânicos do mundo e o desenvolvimento do mercado de alimentos orgânicos está diretamente relacionado à confiança dos consumidores quanto à origem dos produtos. Nesse contexto, as informações dos rótulos e o selo de garantia de produto orgânico facilitam o consumidor identificar os alimentos que estão em conformidade com os regulamentos e normas técnicas vigentes e criam ambiente de confiança em circuitos longos de comercialização para os mercados desses produtos. Considerando a relevância do tema e a escassez de pesquisas de campo sobre rotulagem de alimentos orgânicos, o objetivo da dissertação é analisar a situação da conformidade de rótulos de alimentos orgânicos embalados e comercializados no município do Rio de Janeiro em relação à legislação aplicável, e propor recomendações para as entidades interessadas em uma melhor adequação da rotulagem desses produtos. A pesquisa de campo foi conduzida em 2012 e as amostras analisadas totalizaram 107 produtos, classificados segundo sete categorias, a saber: conservas e antepastos; confeitaria e chocolataria; bebidas; chás; laticínios; barras; e biscoitos e snacks. Os resultados quantitativos e qualitativos da conformidade (e da não-conformidade) da rotulagem das categorias selecionadas poderão ser utilizados por diversas entidades de interesse, como órgãos reguladores, órgãos de defesa do consumidor, organizações não-governamentais, fabricantes e seus fornecedores e consumidores de alimentos orgânicos embalados. / [en] Brazil is among the largest producers of organic food and the development of organic food market is directly concerned to consumer confidence in relation to authenticity of the products. In this context, food labels and organic certification seals provide a wide range of valuable information to make healthier choices easier to consumers and also reliability in long circuits of organic food to market. Considering the importance of the topic and the lack of research with this focus, The objective of this dissertation is two-fold: (i) to analyze the state of compliance of packaged organic food labels commercialized in the city of Rio de Janeiro, focusing on the mandatory labeling information; and (ii) to propose recommendations for organizations interested in compliance of packaged organic food labeling to current Brazilian regulation concerning the selected food categories. The field research was conducted in 2012 and the samples analyzed totaled 107 products, classified into seven categories, as follows: canned and antepastos; confectionery and chocolates; beverages; teas; dairy products; biscuits and snacks; and cereal bars. The quantitative and qualitative results of compliance (and noncompliance) labeling of the selected categories can be used by several entities of interest such as regulators, consumer protection agencies, nongovernmental organizations, manufacturers and their suppliers and organic food consumers.

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