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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.
291

Impacts des changements climatiques sur l'hydrologie des bassins versants dans l'est du Canada = Climate change impacts on catchment hydrology in eastern Canada

Aygün, Okan January 2021 (has links) (PDF)
No description available.
292

[pt] AVALIAÇÃO DA DISTRIBUIÇÃO DE HIDROCARBONETOS EM MATRIZES AMBIENTAIS E AVALIAÇÃO CRÍTICA DAS FERRAMENTAS DE DIAGNÓSTICO DE FONTES / [en] EVALUATION OF HYDROCARBONS DISTRIBUTION IN ENVIRONMENTAL MATRICES AND CRITICAL APPRAISAL OF DIAGNOSTICS SOURCE TOOLS

16 December 2021 (has links)
[pt] A Baía de Guanabara é um ecossistema costeiro cujas alterações na bacia de drenagem ao longo dos anos levaram a sua condição atual de degradação ambiental. As razões diagnósticas e abordagens para a diferenciação de fontes de hidrocarbonetos baseiam-se em dados da literatura e a aplicação destas ao ambiente de estudo é de difícil extrapolação. Este estudo objetiva uma avaliação crítica destas ferramentas através da análise de dois tipos de aportes, o material particulado atmosférico (PM2,5) da Região Metropolitana do Rio de Janeiro e amostras de petróleo e seus produtos de origem brasileira, interpretando os resultados separadamente e relacionando-os aos dados obtidos em amostras de sedimentos desta mesma baía. A concentração de hidrocarbonetos na atmosfera é considerada baixa, onde a precipitação mostrou-se o principal fenômeno atmosférico a influenciar na concentração de material particulado e de hidrocarbonetos. As emissões veiculares, principalmente derivadas de veículos a gasolina, são a principal fonte de hidrocarbonetos para a atmosfera. A concentração de hidrocarbonetos em sedimentos corrobora o forte aporte crônico ao qual a baía está sujeita, sendo a fonte antrópica a principal responsável pelos níveis encontrados. Muitas das razões diagnósticas e seus limites estabelecidos em literatura não correspondem aos valores encontrados nas diferentes matrizes analisadas, existindo também sobreposição de valores entre estas. Os sedimentos da Baía de Guanabara encontram-se em um estado elevado de degradação que interfere na quantificação de fontes e avaliação de aportes. A análise de componentes principais realizada com a proporção relativa dos HPAs em relação aos compostos de mesma massa mostrou-se a metodologia mais adequada para a avaliação de aportes. Os hidrocarbonetos policíclicos aromáticos normalmente não quantificados em estudos ambientais, especialmente os de massa 278 e 276, mostraram maior capacidade em discriminar e separar as amostras geograficamente em relação à origem da contaminação. / [en] Guanabara Bay is a coastal ecosystem where changes in the drainage basin over the years led to its current condition of environmental degradation. The diagnostic reasons and approaches for differentiating hydrocarbon sources are based on literature data and their application in the environment is difficult to extrapolate. This study aims a critical evaluation of these tools by analyzing two types of contributions, the atmospheric particulate matter (PM2,5) in the Metropolitan Region of Rio de Janeiro and samples of petroleum and their products of Brazilian origin, interpreting the results separately and linking them to data obtained in sediment samples from the same bay. The hydrocarbons concentration in the atmosphere is relatively low, where precipitation proved to be the main atmospheric phenomena to influence the concentration of particulate matter and hydrocarbons. The vehicular emissions, mainly derived from gasoline of vehicles, are the main source of hydrocarbons to the atmosphere. The concentration of hydrocarbons in sediments corroborates the intense chronic contribution which the bay is subject, presenting the anthropogenic source as the main cause of levels detected. Many of the diagnostic reasons and limits established in the literature do not correspond to the values found in different matrices analyzed, there is also overlap between these values. The sediments of Guanabara Bay are in a high state of degradation that interferes with the sources quantification and assessment of contributions. A principal component analysis performed with the PAHs relative proportion in relation to the compounds with the same molecular mass proved to be the most appropriate methodology for evaluating contributions. The polycyclic aromatic hydrocarbons not usually quantified in environmental studies, especially the ones with mass 278 and 276, demonstrated greater ability to discriminate and separate samples geographically regarding the contamination origin.
293

Évaluation nutritionnelle systémique de l’enfant en réanimation pédiatrique / Holistic nutritional assessment in critically ill children

Valla, Frédéric 09 December 2019 (has links)
La malnutrition à l’admission en réanimation pédiatrique est fréquente et associée à une augmentation de la morbi-mortalité. Néanmoins, la plupart des études, limitées à une évaluation statique du statut nutritionnel, ne permettent pas une analyse fine de l’impact de la malnutrition. Une approche systémique associerait en plus d’une évaluation nutritionnelle statique, une analyse dynamique dans le temps, une analyse de la composition corporelle et une analyse physiopathologique et étiologique. Cette approche globale a été appliquée dans 4 études prospectives observationnelles, incluant des enfants sévèrement agressés de plus de 36 semaines d’âge corrigé. Il en ressort que la dénutrition globale à l’admission est fréquente (23,7%) et que la cassure des courbes de croissance avant l’admission est associée à une augmentation de la durée de séjour de 3 jours. L’enfant sévèrement agressé présente à l’admission des taux plasmatiques abaissés de 6 micronutriments impliqués dans le stress oxydant (Sélénium, Zinc, Cuivre, Vitamines C, E et bêta-carotène), proportionnellement au nombre de défaillances d’organe. La dénutrition globale et la fonte musculaire acquises en cours de séjour sont des phénomènes fréquents, précoces et importants, associés à une durée de séjour prolongée. Les changements métaboliques liés à l’agression sévère conduisent à une dénutrition. Ces processus adaptatifs sont parfois dépassés et la dénutrition pourra à son tour aggraver le pronostic. La bonne compréhension de la physiopathologie sous-jacente et un suivi systémique et systématique du statut nutritionnel sont les éléments indispensables à l’évaluation des stratégies nutritionnelles / Malnutrition at pediatric Intensive care unit (PICU) admission is frequent and associated with impaired outcomes. However, most studies have focused solely on a static definition. A holistic approach would improve the description of malnutrition: this would include both a static and dynamic assessment of nutritional status, together with body composition assessment and with malnutrition classified based on its patho-physiology and etiology. This holistic assessment of malnutrition has been applied and examined in four observational studies which included critically ill children older than 36 gestational weeks (corrected age). These found that malnutrition was frequent at PICU admission (27.3%) and faltering growth prior to PICU admission was associated with an increased length of PICU stay (+3 days). Critically ill children present at admission with decreased plasma levels of 6 micro-nutrients (Selenium, Copper, Zinc, Vitamin C, E and beta-carotene) involved in anti-oxidative stress pathways. Nutritional status deterioration during PICU stay, and associated muscle mass loss occurred frequently and were intense. This early phenomenon was associated with extended length of PICU stay. A profound critical illness related metabolic shift leads to malnutrition as an adaptive process. However, malnutrition may also negatively impact on outcomes in this setting. These studies have led to a clearer understanding of the underlying patho-physiology. This, combined with a more systematic and holistic nutritional assessment, will enable implementation and assessment of nutritional strategies aiming to improve the functional outcome of critically ill children
294

Compréhension, observation et quantification des mécanismes de rupture ductile par imagerie 3D / Understanding, observation and quantification of ductile failure mechanisms via 3D imaging

Buljac, Ante 28 September 2017 (has links)
Au cours des dernières décennies, des efforts importants ont été menés dans la modélisation des processus de rupture ductile entraînant des progrès substantiels. Cependant, la compréhension complète des mécanismes de rupture ductile dans des états de contraintes spécifiques demeure une question ouverte. Ceci est dû au manque de bases des données expérimentales et à la non validation des modèles pour ces conditions de chargement. Dans ce travail, les acquisitions de données sont principalement obtenues en utilisant la laminographie, ce qui rend possible l'imagerie de régions d'intérêt d'échantillons plats. L'utilisation d'éprouvettes larges (et minces) permet de générer différents états de contraintes et des conditions aux limites pertinentes pour l'ingénierie, qui ne pouvaient pas être évaluées jusqu'à présent en trois dimensions et en essais in-situ à des échelles micrométriques. La corrélation d'images volumiques (DVC) est utilisée pour mesurer les champs de déplacement à l'intérieur des échantillons en acquérant des images de laminographie 3D. Deux classes de matériaux représentatives de deux modes génériques de rupture ductile ont été examinées, à savoir les alliages d'aluminium (rupture par instabilité) et la fonte à graphite sphéroïdal (rupture par croissance de vide et coalescence).L'observation de la microstructure et les interactions déformations-endommagement pour différentes géométries d'échantillons et pour différents niveaux de triaxialité des contraintes associés ont été étudiées pour des alliages d'aluminium à une résolution micrométrique. De plus, un cadre combiné numérique-expérimental (DVC-FE) est introduit pour valider les simulations numériques à l'échelle microscopique pour la fonte à graphite sphéroïdal. Les simulations par éléments finis (FE), qui représentent la microstructure des matériaux étudiés, sont conduites avec des conditions aux limites de Dirichlet extraites des mesures DVC. Enfin, le cadre DVC-FE a été amélioré et utilisé comme une procédure d'identification intégrée pour l'étude du comportement élasto-plastique de la matrice ferritique de la fonte, non seulement en termes de champs cinématiques induits par la microstructure aléatoire, mais aussi avec les niveaux de charge globaux. / In the last few decades significant efforts have been made in modeling ductile failure processes resulting in substantial progress. However, the full understanding of ductile failure mechanisms under specific stress states still remains an open question. This is partly due to missing experimental data and validation of models for such loading conditions.In this work, data acquisitions are mainly obtained by using laminography, which makes the imaging of regions of interest in flat samples possible. The use of large (and thin) specimens allows various stress states and engineering-relevant boundary conditions to be generated, which could not be assessed in three dimensions and in-situ at micrometer scales before. Digital Volume Correlation (DVC) is used for measuring displacement fields in the bulk of samples by registering 3D laminography images. Two material classes that are representative of two generic modes of ductile failure have been examined, namely, Al-alloys (failure by instability) and cast iron (failure by void growth and coalescence). The observation of microstructure and strain-damage interactions at micrometer resolution for various specimen geometries and associated levels of stress triaxiality are studied for Al-alloys. Additionally, a combined computational-experimental (DVC-FE) framework is introduced to validate numerical simulations at the microscopic scale for nodular graphite cast iron. Finite Element (FE) simulations, which account for the studied material microstructure, are driven by Dirichlet boundary conditions extracted from DVC measurements.Last, the DVC-FE framework is upgraded to an integrated identification procedure to probe elasto-plastic constitutive law of the cast iron ferritic matrix not only in terms of kinematic fields induced by the random microstructure but also by overall load levels.
295

[pt] ANÁLISE DE FONTE DE PARES EMARANHADOS BASEADA EM SPDC PARA COMUNICAÇÃO QUANTICA COM MULTIPLEXAÇÃO ESPECTRAL / [en] SIMULATION AND ANALYSIS OF SPDC-BASED ENTANGLED PHOTON PAIR SOURCE FOR QUANTUM COMMUNICATIONS WITH SPECTRAL MULTIPLEXING

BRENO PERLINGEIRO CORREA 08 November 2022 (has links)
[pt] A internet quântica atrai a atenção de muitos pesquisadores e empresas. O elemento essencial para realizá-la é o emaranhamento. A distribuição do emaranhamento permite a transmissão de qubits sem realmente enviá-los pelo canal quântico. Portanto, a fonte que produz esses estados emaranhados deve fazê-lo de forma confiável e com taxa competitiva à de comunicação clássica. Este trabalho apresenta uma ferramenta de simulação para a fonte de pares de fótons emaranhados mais comum, o EPPS baseado em SPDC. Além disso, usando filtros, emulamos o efeito do SPDC dentro de uma cavidade. Otimizando os parâmetros da fonte, obtivemos um ganho de 6dB na taxa de chaves secretas em comparação com um processo SPDC simples. / [en] The quantum internet has dragged the attention of many researchers and companies. The essential element to accomplish it is entanglement. Distributing entanglement allows the transmission of qubits without really sending them through the quantum channel. Therefore, the source that produces these entangled states shall do it reliably and with a competitive rate to classical communication. This work presents a simulation tool for the most common entangled photon pair source, the SPDC-based EPPS. Furthermore, using filters, we can emulate the effect of cavity-enhanced SPDC. Optimizing the parameters of the source, we achieved a 6dB gain on the Secret Key Rate compared to a simple SPDC process.
296

[pt] QUEM É O VERDADEIRO ISRAEL?: ANÁLISE DO AMBIENTE DE MT 25,31-46 À LUZ DOS TEXTOS FONTE E CONTEXTUAIS / [en] WHO IS THE TRUE ISRAEL?: ANALYSIS OF THE ENVIRONMENT IN MT 25:31-46 IN LIGHT OF SOURCE AND CONTEXTUAL TEXTS

VIVIANE PAIXAO DA GAMA 18 September 2023 (has links)
[pt] O presente trabalho debruçou-se sobre o discurso escatológico de Mateus, especificamente sobre Mt 25,31-46, que relaciona o julgamento do Filho do Homem, esperado para os últimos dias, com a prática da justiça, manifesta na realização das obras de misericórdia. Compreende-se que o contexto histórico da comunidade mateana era o pós-guerra de 70 d.C. Esses eventos catastróficos provocaram uma grave crise de identidade nas comunidades judaicas, que passaram a reorganizar a vida na centralidade da Torá, devido à ausência do Templo, que havia sido destruído pelos romanos. Tal ausência também culminou com a perda da liderança judaica, fazendo com que os diversos grupos judaicos, existentes na época, concorressem entre si para assumirem essa função. Entendiam-se como intérpretes autorizados da Torá e, portanto, o verdadeiro Israel. Dentre eles, formou-se uma coalizão que estava em conflito direto com a comunidade mateana, agravando ainda mais a crise que ela vivia. O evangelho de Mateus foi escrito com os propósitos de: levar ordenamento e sentido para a sua comunidade; e consolar os seus membros, profundamente marcados por estes eventos. Para tal, o evangelista fez uso da visão de mundo da escatologia apocalíptica como o julgamento no final dos tempos pelo Filho do Homem e a retribuição dos justos e ímpios. O objetivo deste estudo foi analisar a perícope de Mt 25,31-46, a fim de compreender o ambiente em que o evangelho foi produzido; assim como, a resposta encontrada pelo evangelista em relação à situação de crise no pós-guerra; e os pontos de convergência e divergência com outros grupos judaicos do mesmo período, em especial, o judaísmo formativo, com quem a comunidade mateana está em conflito. Essa análise foi feita por meio da abordagem diacrônica do método histórico crítico, e sincrônica a partir abordagem dos textos fonte e contextual. / [en] The present work focused on the eschatological discourse of Matthew, specifically on Mt 25:31-46, which relates the judgment of the Son of Man, expected for the last days, to the practice of justice manifested in the works of mercy. It is understood that the historical context of the Matthean community was the post-war period of 70 AD. These catastrophic events caused a severe identity crisis among Jewish communities, which began to reorganize their lives around the centrality of the Torah due to the absence of the Temple, which had been destroyed by the Romans. This absence also led to the loss of Jewish leadership, causing various Jewish groups existing at the time to compete for that role. They saw themselves as authorized interpreters of the Torah and therefore the true Israel. Among them, a coalition was formed that was in direct conflict with the Matthean community, further aggravating the crisis it was experiencing. The Gospel of Matthew was written with the purposes of bringing order and meaning to its community, and comforting its members, deeply affected by these events. To this end, the evangelist made use of the worldview of apocalyptic eschatology, such as the judgment at the end of time by the Son of Man and the retribution of the righteous and the wicked. The objective of this study was to analyze the pericope of Mt 25:31-46 in order to understand the environment in which the Gospel was produced, as well as the response found by the evangelist regarding the post-war crisis, and the points of convergence and divergence with other Jewish groups of the same period, especially formative Judaism, with whom the Matthean community is in conflict. This analysis was conducted through the diachronic approach of the historical-critical method, and the synchronic approach of source and contextual texts.
297

[pt] ENTENDENDO CARACTERÍSTICAS E EFEITOS ESTRUTURAIS DE REFATORAÇÃO EM LOTES NA PRÁTICA / [en] UNDERSTANDING CHARACTERISTICS AND STRUCTURAL EFFECTS OF BATCH REFACTORINGS IN PRACTICE

ANA CARLA GOMES BIBIANO 04 November 2019 (has links)
[pt] Refatorar código-fonte consiste em aplicar transformações sobre a estrutura de código-fonte de projetos de software. Refatoração é bastante usada para remover estruturas pobres que dificultam a manutenção de sistemas de software. Poucas transformações isoladas são capazes de remover por completo estruturas pobres, mesmo as mais simples. Por exemplo, encurtar um método longo usualmente requer a extração de vários métodos. Até 60 por cento das transformações são inter-relacionadas e aplicadas em lotes, durante a dita refatoração em lote, ao invés de aplicadas isoladamente. Embora lotes serão frequentes na prática, o conhecimento sobre as características que constituem lotes está fragmentado na literatura. Qual o tamanho usual de lotes? As transformações internas a lotes costumam variar? Não há uma sumarização de conhecimento que responda tais questões. Ademais, são poucas as evidências sobre o efeito de lotes sobre a manutenção de sistemas. Lotes tendem a introduzir ou remover estruturas pobres, especialmente aquelas indicadas por anomalias de código-fonte? A resposta a perguntas como essa é insuficiente para apoiar a aplicação de lotes. Esta dissertação de mestrado apresenta dois estudos experimentais complementares visando resolver as limitações supracitadas. A dissertação começa com uma revisão da literatura sobre refatoração em lote baseada em 29 estudos. Nós identificamos sete características de lotes tais como o escopo de código-fonte afetado pela aplicação de um lote, mais sete tipos de efeito de lotes sobre a manutenção de sistemas, tais como a remoção de anomalias. As características e tipos de efeito identificadas foram sumarizadas por um mapa conceitual. A dissertação encerra-se com uma análise quantitativa de 57 projetos de sistemas abertos e fechados. Ao computar 4.607 lotes com uma heurística, nós descobrimos que a maioria dos lotes leva um único commit para ser aplicada (93 por cento) mas afeta mais do que um só método (90 por cento). Surpreendentemente, a maioria dos lotes introduz (51 por cento) ou não remove (38 por cento) anomalias. Revelamos também lotes até então desconhecidos mas capazes de remover por completo certas anomalias. Esta dissertação sugere trabalhos futuros com base em conflitos identificados na literatura quanto a características e tipos de efeito de lotes. / [en] Code refactoring means applying transformations on the code structure of a software project. Refactoring usually intends to remove poor code structures that harm the software maintenance. Each single transformation rarely suffices to fully remove poor code structures, even the simplest ones. For instance, shortening a long method often requires many method extractions. Up to 60 percent of the refactorings in software projects are constituted of a set of interrelated transformations, the so-called batches, rather than single transformations applied in isolation. Although batches are frequent in practice, the knowledge of batch characteristics is fragmented across studies. What is the usual size of batches? How do transformations vary within a batch? There is no summary that helps to address these questions. More critically, there is little empirical evidence of the batch effect on maintenance. Are batches more likely to introduce or remove poor code structures, especially those spotted by code smells? The current answer to questions like this is insufficient to support the batch application in practice. This Master s dissertation presents two complementary empirical studies that address both aforementioned literature gaps. The dissertation starts with a literature review of batch refactoring with 29 studies. We identified seven batch characteristics such as the scope in which batches are applied to code structures, plus seven types of batch effect on software maintenance, including code smell removal. All batch characteristics and types of effect were summarized in a conceptual map. The dissertation ends with the quantitative analysis of 57 open and closed software projects. From 4,607 heuristic-computed batches, we found that most batches occur entirely within one commit (93 percent) but affect more than just one method (90 percent). Surprisingly, batches mostly end up introducing (51 percent) or not removing (38 percent) code smells. Our results enabled us to reveal certain forms of batches, not documented by previous studies, that are useful to fully remove certain types of code smells.
298

[pt] AVALIAÇÃO PROBABILÍSTICA DE IMPACTO DE ACESSO DE GERADORES RENOVÁVEIS AO SISTEMA DE TRANSMISSÃO / [en] PROBABILISTIC IMPACT ASSESSMENT OF RENEWABLE GENERATOR CONNECTION TO THE TRANSMISSION

DAFINY LORENA RIBEIRO MARQUES 12 September 2024 (has links)
[pt] O aumento significativo de pequenas usinas de geração, impulsionado pela privatização do mercado de oferta de energia elétrica e avanços tecnológicos, apresenta desafios no acesso desses empreendimentos ao sistema de transmissão. Em algumas regiões, o aumento da implantação de usinas cria filas para acesso à rede elétrica, potencialmente resultando em uma escassez de margem de transmissão. Isso é caracterizado pela saturação de escoamento de potência em áreas geográficas com elevado potencial para fontes renováveis (como eólica e solar), impactando negativamente o planejamento e operação do sistema de transmissão. Esta Dissertação de Mestrado propõe uma abordagem de avaliação probabilística dos riscos associados à entrada de novos geradores, com destaque para fontes eólicas e fotovoltaicas. A utilização do fluxo de potência probabilístico, por meio da simulação de Monte Carlo, estende as capacidades do método determinístico, proporcionando uma melhor representação da intermitência inerente das fontes renováveis variáveis e possíveis contingências de equipamentos. Os estudos realizados no sistema teste IEEE RTS 79 - 24 barras, considerando a incorporação de usinas renováveis, permitem compreender a importância do método probabilístico no fornecimento de informações mais representativas aos tomadores de decisão. A proposta de reformulação do processo de acesso, adaptando métodos de cálculo para refletir a complexidade do cenário atual de geração de energia, emerge como um caminho promissor à utilização eficiente do sistema de transmissão, especialmente diante da crescente presença de fontes renováveis. / [en] The significant increase in small generation plants, driven by the privatization of the electricity supply market and technological advances, presents challenges in terms of their access to the transmission system. In some regions, the increasing deployment of power plants creates queues for access to the grid, potentially resulting in a transmission margin shortage. This is characterized by the saturation of power flow in geographical areas with high potential for renewable sources (such as wind and solar), negatively impacting the planning and operation of the transmission system. This Master s Thesis proposes a probabilistic approach to assessing the risks associated with the entry of new generators, especially wind and photovoltaic sources. The use of probabilistic power flow, through Monte Carlo simulation, extends the capabilities of the deterministic method, providing a better representation of the inherent intermittency of variable renewable sources and possible equipment contingencies. The studies carried out on the IEEE RTS 79 - 24-bus test system, considering the incorporation of renewable power plants, allow us to understand the importance of the probabilistic method in providing decision-makers with more representative information. The proposal to reformulate the access process, adapting calculation methods to reflect the complexity of the current energy generation scenario, emerges as a promising way of making efficient use of the transmission system, especially given the growing presence of renewable sources.
299

Influent generator : towards realistic modelling of wastewater flowrate and water quality using machine-learning methods

Li, Feiyi 12 November 2023 (has links)
Depuis que l'assainissement des eaux usées est reconnu comme un des objectifs de développement durable des Nations Unies, le traitement et la gestion des eaux usées sont devenus plus importants que jamais. La modélisation et la digitalisation des stations de récupération des ressources de l'eau (StaRRE) jouent un rôle important depuis des décennies, cependant, le manque de données disponibles sur les affluents entrave le développement de la modélisation de StaRRE. Cette thèse vis e à faire progresser la modélisation des systèmes d'assainissement en général, et en particulier en ce qui concerne la génération dynamique des affluents. Dans cette étude, différents générateurs d'affluent (GA), qui peuvent fournir un profil d'affluent dynamique, ont été proposés, optimisés et discutés. Les GA développés ne se concentrent pas seulement sur le débit, les solides en suspension et la matière organique, mais également sur les substances nutritives telles que l'azote et le phosphore. En outre, cette étude vise à adapter les GA à différentes applications en fonction des différentes exigences de modélisation. Afin d'évaluer les performances des GA d'un point de vue général, une série de critères d'évaluation de la qualité du modèle est décrite. Premièrement, pour comprendre la dynamique des affluents, une procédure de caractérisation des affluents a été développée et testée pour une étude de cas à l'échelle pilote. Ensuite, pour générer différentes séries temporelles d'affluent, un premier GA a été développé. La méthodologie de modélisation est basée sur l'apprentissage automatique en raison de ses calculs rapides, de sa précision et de sa capacité à traiter les mégadonnées. De plus, diverses versions de ce GA ont été appliquées pour différents cas optimisées en fonction des disponibilités d'études et ont été des données (la fréquence et l'horizon temporel), des objectifs et des exigences de précision. Les résultats démontrent que : i) le modèle GA proposé peut être utilisé pour générer d'affluents dynamiques réalistes pour différents objectifs, et les séries temporelles résultantes incluent à la fois le débit et la concentration de polluants avec une bonne précision et distribution statistique; ii) les GA sont flexibles, ce qui permet de les améliorer selon différents objectifs d'optimisation; iii) les GA ont été développés en considérant l'équilibre entre les efforts de modélisation, la collecte de données requise et les performances du modèle. Basé sur les perspectives de modélisation des StaRRE, l'analyse des procédés et la modélisation prévisionnelle, les modèles de GA dynamiques peuvent fournir aux concepteurs et aux modélisateurs un profil d'affluent complet et réaliste, ce qui permet de surmonter les obstacles liés au manque de données d'affluent. Par conséquent, cette étude a démontré l'utilité des GA et a fait avancer la modélisation des StaRRE en focalisant sur l'application de méthodologies d'exploration de données et d'apprentissage automatique. Les GA peuvent donc être utilisés comme outil puissant pour la modélisation des StaRRE, avec des applications pour l'amélioration de la configuration de traitement, la conception de procédés, ainsi que la gestion et la prise de décision stratégique. Les GA peuvent ainsi contribuer au développement de jumeaux numériques pour les StaRRE, soit des système intelligent et automatisé de décision et de contrôle. / Since wastewater sanitation is acknowledged as one of the sustainable development goals of the United Nations, wastewater treatment and management have been more important then ever. Water Resource Recovery Facility (WRRF) modelling and digitalization have been playing an important role since decades, however, the lack of available influent data still hampers WRRF model development. This dissertation aims at advancing the field of wastewater systems modelling in general, and in particular with respect to the dynamic influent generation. In this study, different WRRF influent generators (IG), that can provide a dynamic influent flow and pollutant concentration profile, have been proposed, optimized and discussed. The developed IGs are not only focusing on flowrate, suspended solids, and organic matter, but also on nutrients such as nitrogen and phosphorus. The study further aimed at adapting the IGs to different case studies, so that future users feel comfortable to apply different IG versions according to different modelling requirements. In order to evaluate the IG performance from a general perspective, a series of criteria for evaluating the model quality were evaluated. Firstly, to understand the influent dynamics, a procedure of influent characterization has been developed and experimented at pilot scale. Then, to generate different realizations of the influent time series, the first IG was developed and a data-driven modelling approach chosen, because of its fast calculations, its precision and its capacity of handling big data. Furthermore, different realizations of IGs were applied to different case studies and were optimized for different data availabilities (frequency and time horizon), objectives, and modelling precision requirements. The overall results indicate that: i) the proposed IG model can be used to generate realistic dynamic influent time series for different case studies, including both flowrate and pollutant concentrations with good precision and statistical distribution; ii) the proposed IG is flexible and can be improved for different optimization objectives; iii) the IG model has been developed by considering the balance between modelling efforts, data collection requirements and model performance. Based on future perspectives of WRRF process modelling, process analysis, and forecasting, the dynamic IG model can provide designers and modellers with a complete and realistic influent profile and this overcomes the often-occurring barrier of shortage of influent data for modelling. Therefore, this study demonstrated the IGs' usefulness for advanced WRRF modelling focusing on the application of data mining and machine learning methodologies. It is expected to be widely used as a powerful tool for WRRF modelling, improving treatment configurations and process designs, management and strategic decision-making, such as when transforming a conventional WRRF to a digital twin that can be used as an intelligent and automated system.
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Étude comparative des traitements de semences sans fongicide chez les céréales à l'aide de l'ozone et de l'oxygène pur

Neched, Hassiba 23 April 2018 (has links)
La fonte des semis et la pourriture des racines font partie des maladies céréalières des grandes cultures au Québec. Elles sont causées par deux agents pathogènes, le Fusarium graminearum et le Bipolaris sorokiniana contaminant la semence céréalière, en particulier le blé et l’orge, ce qui entraîne à la fois une baisse de la levée et un rendement moins élevé. Des agriculteurs biologiques tentent de trouver un traitement de semences sans fongicide afin de lutter contre ces champignons, qui sont néfastes pour l’agriculture céréalière. Notre projet a comme objectif d’utiliser l’action oxydative de l’oxygène ou l’ozone humidifié pour engendrer un stress oxydatif afin de diminuer l’impact des deux agents pathogènes responsables de cette maladie, le F. graminearum et le B. sorokiniana, tout en préservant le pouvoir germinatif de ces semences. La dose en agent oxydant, le débit des gaz oxydants (ozone et /ou oxygène) ainsi que le temps d’exposition constituent les paramètres clés à optimiser pour ce traitement oxydatif et la cinétique de germination des graines céréalières traitées. Un tel traitement semblait prometteur pour la semence de blé. Il l’était toutefois un peu moins pour la semence d’orge en raison de son enveloppe assez rigide qui a rendu difficile la pénétration de l’ozone et l’oxygène. Pour remédier à ce problème, nous avons fait des tests préliminaires sur l’orge en utilisant la sonication par ultrasons comme prétraitement de l’orge avant le traitement oxydatif. Les résultats obtenus suggèrent qu’un tel traitement est prometteuret non négligeable afin d’optimiser notre traitement oxydatif et de permettre par la suite de réduire les agents responsables de la maladie sans nuire à la qualité des semences de céréales. Ce point a été abordé dans nos travaux par un test préliminaire sur l’orge, et cette approche s’annonce très prometteuse pour nos recherches futures. / Seedling blight and root rot are part of cereal diseases of field crops in Quebec. They are caused by two pathogens, Fusarium graminearum and Bipolaris sorokiniana, which contaminate the seed grain, especially wheat and barley, which causes both decreased, lift and lower performance. Organic farmers are trying to find a seed without fungicide treatment to fight against these fungi, which are harmful to cereal farming. Our project has as goal to use the oxidative action of oxygen or ozone moistened to cause oxidative stress in order to reduce the impact of the two pathogens responsible for this disease, F. graminearum and B. sorokiniana, while preserving the germinability of the seeds. The dose in oxidizing agent, the flow of oxidizing gases (ozone and/or oxygen) and the time of exposure are key parameters to optimize for this oxidative treatment and germination kinetics treated cereal seed. Such treatment looked promising for the seed of wheat. It was however a little less for the seed of barley because it’s fairly rigid envelope which made difficult the penetration of ozone and oxygen. To remedy this problem, we have preliminary tests on barley using sonication ultrasonic as pre-treatment of barley oxidative pre-treatment. The results suggest that, such treatment is promising and significant in order to optimize our oxidative treatment and subsequently, reduce the causative agents of disease without harming the quality of cereal seed. This point has been addressed in our work by a preliminary test on barley, and this approach looks very promising for our future research.

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