Metodologia para monitoramento do assoreamento de reservatórios : prposta para a UHE Mauá

Orientadores : Prof. Dr. Pedro Luis Faggion, Prof. Dr. Luis Augusto Koenig VeigaDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Ciências Geodésicas. Defesa: Curitiba, 19/03/2015Inclui referências : fls. 109-115Resumo: Com o objetivo de desenvolver uma metodologia para a monitoramento do assoreamento de determinada área do reservatório da Usina Hidrelétrica Mauá, situada no rio Tibagi, entre as divisas dos municípios de Ortigueira e Telêmaco Borba no estado do Paraná, executou-se o levantamento batimétrico à montante da barragem em uma área de 170382,44m². Na coleta de dados, foram realizadas linhas de sondagens regulares, perpendiculares ao curso d'água, para obter a superfície do fundo do lago; e linhas de sondagens de verificações, longitudinais ao fluxo do rio, para calcular as incertezas verticais e o Padrão de Exatidão Cartográfica dos produtos gerados. O volume assoreado foi calculado comparando os dados provenientes do levantamento batimétrico com a superfície de referência obtida pelo recobrimento aéreo feito com a levantamento Laser antes do enchimento do reservatório. A redução das sondagens batimétricas com relação ao nível instantâneo da água do reservatório foi feito por três técnicas distintas de coleta de dados. As diferenças volumétricas dos Modelos Digitais do Terreno, da malha triangular foram calculas no sistema de informações geográficas ArcGIS. As análises das diferenças entre as superfícies do fundo foram feitas através processamento digital de imagens utilizando a interpolação dos modelos digitais pelo método da Vizinhança Natural, estrutura de dados matricial. Após a análise das diferenças entre os modelos, constatou-se que elas não representam apenas o volume assoreado do reservatório, mas também diferenças de elevação observadas em locais em que a presença de vegetação arbórea prejudica a definição real do fundo do lago. A aplicação de diferentes métodos (nível d' água observado por régua linimétrica, nível d' água rastreado com RTK estático e nível d' água coletado com RTK em movimento) de redução das sondagens batimétricas demonstrou que os dois primeiros métodos apresentaram resultados equivalentes, mostrando a viabilidade da aplicação dos mesmos para UHE Mauá. O conjunto de experimentos permitiu o estabelecimento de uma metodologia a ser aplicada na usina. Palavras-Chave: Monitoramento do Assoreamento, Levantamento Batimétrico e Modelo Digital do Terreno.Abstract: In order to develop a methodology for the monitoring of silting of a particular area of the Mauá Hydroelectric Power Plant reservoir, located on the Tibagi River, between the currencies of the cities of Ortigueira and Telemaco Borba in the state of Paraná, it was executed the bathymetric survey upstream of the dam in an area of 170382,44m². In data collection were carried out regular surveys lines, perpendicular to the water course, to generate the surface of the lake bottom, and verification survey lines, longitudinal to river flow, to calculate the vertical uncertainties and the Cartographic Accuracy Standard of the products generated. The silted volume was calculated by comparing the descendant data of the bathymetric survey with the reference surface obtained by the aerial flight done with the Laser Scanner technology before filling the reservoir. The reduction of bathymetric surveys with respect to the instantaneous level of the reservoir water it was made by three different techniques of data collection. The volumetric differences of Digital Terrain Models, triangular network were calculated in the geographic information system ArcGIS. The analysis of the differences between the surfaces of the fund were made through digital image processing using the interpolation of digital models by the method of Natural Neighbor in matrix format. After analyzing the differences between the models, it was found that they not only represent the silted volume of the reservoir, but also differences in elevation observed in places in which the presence of arbustive vegetation affect the definition studies of the lake bottom. The application of different methods of reducing bathymetric surveys (water level measured by limnimetric scale, water level tracked with Estatic RTK and water level collected with Moving RTK) showed that the first two methods presented equivalents results, showing the feasibility of application of them for the Maua hydroeletric power plant silting surveying. The experiments allowed the establishment of a methodology to be applied in UHE Maua. Key words: Monitoring of Sedimentation, Bathymetric Survey and Digital Terrain Model

AVALIAÇÃO DE MÉTODOS DE REDUÇÃO DE SONDAGENS BATIMÉTRICAS AO NÍVEL D’ÁGUA INSTANTÂNEO PARA MONITORAMENTO DE ASSOREAMENTO: ESTUDO DE CASO DO RESERVATÓRIO DA USINA HIDRELÉTRICA MAUÁ

O setor elétrico brasileiro está estruturado para garantir o fornecimento de energia elétrica à toda a nação, sendo que a geração é feita em sua maioria através de usinas hidrelétricas, onde o reservatório desempenha peça fundamental no processo de geração. O assoreamento de reservatórios pode impactar diretamente na operação e manutenção de usinas hidrelétricas, reduzindo a sua capacidade de armazenamento e vida útil. O monitoramento e a avaliação do volume assoreado do reservatório é uma importante ferramenta para o acompanhamento do processo de assoreamento e para fornecer as informações necessárias para embasar a tomada de decisões de forma a evitar a interrupção no processo de geração de energia, bem como danos ambientais. Neste trabalho foram testados três formas diferentes de realizar a redução do nível d’água instantâneo em levantamentos realizados com um ecobatímetro voltadas para o monitoramento de reservatórios: observações com RTK móvel, medições feitas na margem do reservatório com o RTK estático e leituras da régua linimétrica. Através do cálculo das incertezas verticais totais e teste estatístico das duas médias constatou-se que as duas ultimas técnicas apresentaram resultados equivalentes e sua aplicação é viável na área de estudo

Rendimiento de las celdas solares de heterounión ZnO/Cu2O modificadas con óxido de grafeno

[EN] We report the fabrication of ZnO/Cu2O heterojunction solar cells by means of the electrodeposition technique. The effect of electrolyte medium for the ZnO deposition, annealing treatment and interface modification with graphene oxide (GO) layer on the photoelectrical properties was analyzed. The electrochemical results indicated a markedly dependent Cu2O film electrodeposition on the GO-modified ZnO films. The modification of ZnO/Cu2O interface with GO nanosheets and annealing treatment results in improved interface properties, varying morphology and defects in ZnO lattice that further lead to enhanced performance of the proposed heterojunction solar cells. While the obtained results indicate that the properties of GO coating need to be tailored for improved performance, a synergetic effect of the GO addition and annealing treatment on the photoelectric properties of the electrodeposited heterojunction is achieved. (C) 2019 SECV. Published by Elsevier Espana, S.L.U.[ES] Se presenta la fabricación de celdas solares de heterounión de ZnO/Cu2O obtenidas mediante la técnica de electrodeposición. Se analizó el efecto del electrolito utilizado para la deposición de ZnO, el tratamiento térmico aplicado y la modificación de la interfaz con una capa de óxido de grafeno (GO) sobre las propiedades fotoeléctricas. Los resultados electroquímicos indicaron que existe una marcada dependencia de electrodeposición de capa de Cu2O sobre las películas de ZnO modificadas con GO. La modificación de la interfaz ZnO/Cu2O con nanohojas de GO y el tratamiento térmico dan como resultado mejoras en las propiedades de la interfaz, una morfología variable y defectos en la red de ZnO que conducen a un mejor rendimiento de las celdas solares de heterounión propuestas. Si bien los resultados obtenidos indican que las propiedades del recubrimiento de GO deben adaptarse para mejorar el rendimiento, se logra un efecto sinérgico del tratamiento de adición y térmico de GO aplicados sobre las propiedades fotoeléctricas de la heterounión electrodepositada.Financial support from Escuela Politécnica Nacional (project number PIMI 15-09), Secretaría de Educación Superior, Ciencia, Tecnología e Innovación (SENESCYT) of Ecuador, Romanian National Authority for Scientific Research and Innovation CNCS ¿ UEFISCDI (project number PN-III-P1-1.1-TE-2016-1544), Spanish government MINECO (projects MAT2016-75586-C4-2-P and MAT2015-71070-REDC) and from Generalitat Valenciana (project PROMETEO 2018/123 ¿ EFIMAT) is gratefully acknowledged. In addition, authors would like to thank to the Microscopy Service of UPV and Dr. David Busquets-Mataix for useful advice.Rosas-Laverde, NM.; Pruna, AI.; Cembrero Gil, J.; Orozco-Messana, J.; Manjón, F. (2019). Performance of graphene oxide-modified electrodeposited ZnO/Cu2O heterojunction solar cells. Boletín de la Sociedad Española de Cerámica y Vidrio. 58(6):263-273. https://doi.org/10.1016/j.bsecv.2019.06.002S263273586Kathalingam, A., Vikraman, D., Kim, H.-S., & Park, H. J. (2017). Facile fabrication of n-ZnO nanorods/p-Cu 2 O heterojunction and its photodiode property. Optical Materials, 66, 122-130. doi:10.1016/j.optmat.2017.01.051Panigrahi, S., Nunes, D., Calmeiro, T., Kardarian, K., Martins, R., & Fortunato, E. (2017). Oxide-Based Solar Cell: Impact of Layer Thicknesses on the Device Performance. ACS Combinatorial Science, 19(2), 113-120. doi:10.1021/acscombsci.6b00154Makhlouf, H., Weber, M., Messaoudi, O., Tingry, S., Moret, M., Briot, O., … Bechelany, M. (2017). Study of Cu 2 O\ZnO nanowires heterojunction designed by combining electrodeposition and atomic layer deposition. 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Influence of acid hydrolysis, saponification and sample clean-up on the measurement of phytosterols in dairy cattle feed using GC–MS and GC with flame ionization detection

The fortification of processed foods including dairy products is increasingly commonplace with phytosterols among many compounds used to improve the nutritional value of food products. It is also increasingly common practice for some dairy cattle feeds to be fortified for their potential to increase phytosterol levels in milk. In this study, a combined, streamlined protocol using acid hydrolysis, saponification and sample clean-up was developed to enable the rapid and reliable measurement of phytosterols. The method was developed with focus on streamlining the overall technique to make it suitable for commercial laboratories, to reduce labor and consumable costs, while maintaining accuracy. A total of 12 different feed types commonly used in the dairy industry were analyzed with the highest and lowest sterol contents found in cotton seed oil and tannin with average phytosterol contents of 256 and  0.99, the method was validated for milk to enable feed comparison studies with respect to the total phytosterol content in raw milk

Design of experiments by active learning for the identification of dynamical biological systems

Ces dernières années, les progrès continuels des techniques de criblage et de séquençage à haut débit ont nourri la biologie des systèmes, ouvrant la voie à l’identification de systèmes dynamiques biologiques tels que des réseaux de régulation génique. Cependant, l’insuffisance et la mauvaise qualité des données expérimentales se traduisent trop souvent par des estimations incertaines des paramètres d’intérêt des systèmes étudiés : ces incertitudes peuvent être levées en produisant de nouvelles données dans des conditions expérimentales variées, ce qui implique un coût potentiellement élevé. Dans cette thèse, nous proposons un nouvel algorithme d’apprentissage actif, destiné à recommander de manière séquentielle les expériences les plus utiles à l’identification de systèmes dynamiques biologiques modélisés par des équations différentielles. Le problème est formulé sous la forme d’un jeu à un joueur : le joueur se voit attribuer un budget dédié aux expérimentations, et un coût spécifique est affecté à chaque expérience ; à chaque tour, il est amené à choisir une, voire plusieurs expériences réalisées sur le système étudié dans le but de maximiser la qualité de l’estimation, une fois le budget épuisé. Notre approche, intitulée « ExperimentalDEsign for Network inference » (EDEN), s’appuie sur la classe d’algorithme UCT (Upper Confidence bounds for Trees search) qui allie la souplesse de la recherche arborescente de Monte-Carlo à l’efficacité des algorithmes de bandits multi-bras pour parcourir l’ensemble des séquences d’expériences possibles en privilégiant surtout celles qui sont les plus prometteuses. EDEN présente le grand avantage d’anticiper les expériences suivantes en sélectionnant à chaque tour des expériences sachant qu’elles seront suivies par un certain nombre d’autres expériences. Illustrée sur deux cas d’étude, le réseau de signalisation JAK/STAT et un des réseaux de régulation génique proposé dans la compétition internationale DREAM7, EDEN, entièrement automatique, obtient de très bonnes performances pour un budget limité et un large choix d’expériences (perturbations, mesures).Continuous progress in screening and high-throughput sequencing techniques in recent years paves the way for the identification of dynamic biological systems such as gene regulatory networks. However, the scarcity of the experimental data often leads to anuncertain estimation of parameters of interest. These uncertainties can be solved by generating new data in different experimental conditions, which induces additional costs. This thesis proposes a general active learning approach to develop tools of sequential experimental design for the identification of dynamical biological systems. The problem is formulated as a one-player game : the player has a budget dedicated for his experiments, each experiment has a different cost ; at every turn, he chooses one or more experiments to be performed on the system with the ultimate aim of maximizing the quality of the estimate, until the available budget is exhausted. The proposed approach called Experimental DEsign for Network inference (EDEN), is based on UCT (Upper Confident bounds for Trees) algorithm which combines Monte-Carlo tree search algorithms with multi-arm bandits to perform an effective exploration of the possible sequences of experiments. A strong point of the approach is anticipation : an experiment is selected at each round, knowing that this round will be followed by a number of other experiments, according to the available budget. This generic approach is rolled out in parameter estimation in nonlinear ordinary differential equations using partial observations. EDEN is applied on two problems : signaling network and gene regulatory network identification. Compared to the competitors, it exhibits very good results on a DREAM7 challenge where a limited budget and a wide range of experiments (perturbations, measurements) are available

Conduite d'expériences par apprentissage actif pour l'identification de systèmes dynamiques biologiques : application à l'estimation de paramètres d'équations différentielles ordinaires

Continuous progress in screening and high-throughput sequencing techniques in recent years paves the way for the identification of dynamic biological systems such as gene regulatory networks. However, the scarcity of the experimental data often leads to anuncertain estimation of parameters of interest. These uncertainties can be solved by generating new data in different experimental conditions, which induces additional costs. This thesis proposes a general active learning approach to develop tools of sequential experimental design for the identification of dynamical biological systems. The problem is formulated as a one-player game : the player has a budget dedicated for his experiments, each experiment has a different cost ; at every turn, he chooses one or more experiments to be performed on the system with the ultimate aim of maximizing the quality of the estimate, until the available budget is exhausted. The proposed approach called Experimental DEsign for Network inference (EDEN), is based on UCT (Upper Confident bounds for Trees) algorithm which combines Monte-Carlo tree search algorithms with multi-arm bandits to perform an effective exploration of the possible sequences of experiments. A strong point of the approach is anticipation : an experiment is selected at each round, knowing that this round will be followed by a number of other experiments, according to the available budget. This generic approach is rolled out in parameter estimation in nonlinear ordinary differential equations using partial observations. EDEN is applied on two problems : signaling network and gene regulatory network identification. Compared to the competitors, it exhibits very good results on a DREAM7 challenge where a limited budget and a wide range of experiments (perturbations, measurements) are available.Ces dernières années, les progrès continuels des techniques de criblage et de séquençage à haut débit ont nourri la biologie des systèmes, ouvrant la voie à l’identification de systèmes dynamiques biologiques tels que des réseaux de régulation génique. Cependant, l’insuffisance et la mauvaise qualité des données expérimentales se traduisent trop souvent par des estimations incertaines des paramètres d’intérêt des systèmes étudiés : ces incertitudes peuvent être levées en produisant de nouvelles données dans des conditions expérimentales variées, ce qui implique un coût potentiellement élevé. Dans cette thèse, nous proposons un nouvel algorithme d’apprentissage actif, destiné à recommander de manière séquentielle les expériences les plus utiles à l’identification de systèmes dynamiques biologiques modélisés par des équations différentielles. Le problème est formulé sous la forme d’un jeu à un joueur : le joueur se voit attribuer un budget dédié aux expérimentations, et un coût spécifique est affecté à chaque expérience ; à chaque tour, il est amené à choisir une, voire plusieurs expériences réalisées sur le système étudié dans le but de maximiser la qualité de l’estimation, une fois le budget épuisé. Notre approche, intitulée « ExperimentalDEsign for Network inference » (EDEN), s’appuie sur la classe d’algorithme UCT (Upper Confidence bounds for Trees search) qui allie la souplesse de la recherche arborescente de Monte-Carlo à l’efficacité des algorithmes de bandits multi-bras pour parcourir l’ensemble des séquences d’expériences possibles en privilégiant surtout celles qui sont les plus prometteuses. EDEN présente le grand avantage d’anticiper les expériences suivantes en sélectionnant à chaque tour des expériences sachant qu’elles seront suivies par un certain nombre d’autres expériences. Illustrée sur deux cas d’étude, le réseau de signalisation JAK/STAT et un des réseaux de régulation génique proposé dans la compétition internationale DREAM7, EDEN, entièrement automatique, obtient de très bonnes performances pour un budget limité et un large choix d’expériences (perturbations, mesures)

Conception de schémas distributifs pour l'aérodynamique stationnaire et instationnaire

Le sujet concerne la simulation d'écoulements de fluides compressibles à l'aide de schémas distributifs. La première partie est consacrée à la résolution numérique de lois de conservation hyperboliques stationnaires. Nous présentons une méthode de construction de schémas distributifs stables et précis pour des problèmes scalaires. Puis, en utilisant le concept d'ondes simples, nous généralisons cette technique au cas de systèmes linéaires symétrisables. Nous étendons formellement cette construction aux équations d'Euler. Le but de la seconde partie est de construire des schémas distributifs décentrés pour des problèmes hyperboliques instationnaires. Pour réaliser cela, nous évaluons un résidu espace-temps basé sur une approximation espace-temps de la solution. Nous développons de nouveaux schémas distributifs qui sont des extensions des schémas distributifs classiques. De nombreux résultats numériques sont présentés afin de démontrer la stabilité et la précision de la méthode.BORDEAUX1-BU Sciences-Talence (335222101) / SudocSudocFranceF

Analyse descriptive des facteurs de risque liés aux mammites dans les élevages d'une clientèle des Ardennes appliquant la démarche GTV partenaire

Les mammites constituent la première pathologie en élevage laitier. Elles représentent la première source de dépense en médicaments et en soins vétérinaires. GTV Partenaire, guide de bonnes pratiques en matière de traitement, a été mis en place dans des élevages des Ardennes dans le but de sensibiliser les éleveurs au traitement raisonné. L enquête veut d une part évaluer le rôle de l action GTV Partenaire dans la gestion des pratiques à risque liées à la traite, à l environnement et aux traitements, et d autre part analyser la bonne application du protocole et l évolution du statut sanitaire des troupeaux en matière de mammites. Après présentation d une synthèse bibliographique qui rappelle l épidémiologie et les plans de lutte contre les mammites, l auteur expose une enquête réalisée sur 14 élevages où l action GTV Partenaire a été mise en place. Dans chaque élevage, l auteur a effectué une visite de traite, une visite de bâtiment et a posé des questions relatives au traitement des mammites et à la politique de réforme. Dans 10 exploitations soumises à une visite d élevage lors de la mise en place de l action GTV Partenaire, le nombre de pratiques défectueuses liées à la traite et au bâtiment a stagné. Dans les 4 autres, il a diminué. Dans les 14 élevages, les facteurs de risque liés au traitement ont régressé. L enquête a révélé une bonne prise en compte des mesures en matière de traitement durant la période de lactation et la période de tarissement dans les élevages où GTV Partenaire a été mis en place, mais les éleveurs n ont pas été sensibilisés aux facteurs de risque liés à la traite et à l environnement. En outre, notre recherche montre une amélioration globale des résultats relatifs au statut sanitaire des troupeaux depuis l intervention de GTV Partenaire.MAISONS-ALFORT-Ecole Vétérin (940462302) / SudocSudocFranceF

Extraterrestrial 3He shows that Mesozoic marl-limestone alternations are mainly driven by CaCO3 variations at the astronomical timescale

IntroductionMarl-limestone alternations are well known rhythmical inter-bedded deposits that commonly occur in many hemipelagic to pelagic deposits of the Phanerozoic. It is quite well established that the origin of these lithological variations are astronomically-driven climatic variations (22, 41, 100 and 405 ka being the main periods) e.g. [1]. However, the exact sedimentological control is not clear: several models attribute these alternations to cyclic changes in the carbonate flux, whereas the terrigenous silicoclastic flux remained relatively constant. On the opposite, some models suggest that the carbonate flux was constant while the silicoclastic flux changed cyclically.Material and methodsTo disentangle these different scenarios, we collected marlstone and limestone samples from two sedimentary successions of Bajocian, Middle Jurassic (3 marl-limestone- couplets over 3.5 m) and Valanginian, Lower Cretaceous (1 marl-limestone couplet over 1 m) age from the Southern French Alps (Barles). We measured their carbonate contents, the nannofossil proportion, as well as their extraterrestrial 3He (3HeET) concentrations in ~200mg decarbonated aliquots.Results and discussionThe carbonate content ranges from 45% in marls to 86% in limestones. Importantly, for all samples, measured 3HeET concentrations are constant in the silicoclastic fractions, within uncertainties. Hence, our results indicate that sedimentation rates at the astronomical timescale in the examined examples were mainly controlled by large changes in the CaCO3 net fluxes, leading to variable dilution of the terrigenous and 3HeET fractions. Nannofossil counting shows that pelagic CaCO3 fluxes of coccolithophores are inversely correlated to the total CaCO3 along the marl-limestone alternations and represent less than 4% of the total carbonate content. Hence, in this setting, these marl-limestone alternations were more probably driven by variations in the CaCO3 supply from the nearby carbonate platform. Finally, assuming a constant 3HeET flux of 0.1 pcc/cm2/ka [2], and the whole thickness of Bajocian and Valanginian strata in this region, the measured concentrations imply sedimentation rates that are broadly compatible with current duration estimates of these two stages.References:Eldrett J. S. et al. (2015) Plan. Sci. Let., 423,98-113.Farley K.A. et al. (2012) 84, 314-328