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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.
31

Études épidémiologiques régionales et nationales des infections virales respiratoires sévères de l’enfant : intérêts pour la prise en charge préventive et curative / Regional and national epidemiological studies on respiratory viral infections in children : preventive and curative interests

Fléchelles, Olivier 30 November 2018 (has links)
Les virus respiratoires induisent de nombreuses et fréquentes pathologies en pédiatrie avec une morbidité importante. Ces virus sont bien connus car étudiés depuis longtemps mais ils sont en évolution constante. L’apparition des antibiotiques, des antiviraux, des soins intensifs, de la vaccination, les connaissances sur l’hygiène ont transformé l’impact de ces virus sur les populations humaines. Nos modes de vie principalement citadins favorisent la diffusion virale locale par le regroupement de presque tous les enfants dans des crèches ou des écoles. De même l’explosion récente des moyens de transport en particulier aérien qui ont reliés physiquement tous les pays du monde entre eux et qui accentuent la diffusion virale mondiale. Faut-il appliquer les mêmes raisonnements dans tous les pays du monde pour lutter contre ces infections ? Cette thèse apporte de nouvelles connaissances sur ce sujet en se focalisant sur les virus influenza et le virus respiratoire syncytial :1) Pendant la pandémie H1N1 au Canada, la mise en évidence de l’augmentation des hospitalisations des enfants asthmatiques, paradoxalement moins souvent ventilés durant leurs séjours en réanimation pédiatrique.2) L’intérêt de la vaccination contre le virus pandémique H1N1 pour diminuer le recours à la ventilation assistée chez les enfants hospitalisés en réanimation pédiatrique.3) Le Canada n’a pas connu de 3ème vague pandémique en raison d’une campagne vaccinale massive qui bien que tardive, a été efficace même 1 an plus tard.(4) La saisonnalité de la bronchiolite dans les régions tropicales est très différente de celle retrouvée dans les pays tempérés et nécessite de réajuster les recommandations de prise en charge à l’aune des données localesEn décrivant la cinétique et l’impact de la pandémie grippale de 2009 sur les enfants hospitalisés en soins intensifs pédiatriques au Canada d’Octobre 2009 à Mars 2011, en comparant cette cohorte à une cohorte similaire en France Hexagonale, et en décrivant 2 épidémies de VRS en Martinique en 2007 et 2008 pour confronter ces données avec celles décrites dans les pays tempérés, ce travail illustre combien nos connaissances doivent toujours être remises en question du fait de l’évolution du climat, de l’évolution de la société et de l’évolution des connaissances médicales / Respiratory viruses are responsible for much pediatric pathology with significant morbidity. These viruses are well known for a long time but are subject to constant changes. The development of antibiotics, antivirals, intensive care, vaccination, knowledge on hygiene has modified the impact of these viruses on human populations. Our predominantly urban lifestyles support local viral spread by bringing almost all children together in nurseries or schools. In the same way, the large use of modern transport facilities especially air transport (which connect all continents between them) facilitate the world viral spread. In this new environment, should we apply the same medical reasoning all over the world to fight against these infections? This thesis brings new knowledge on this topic, focusing on influenza virus and syncytial respiratory virus:1) During Influenza A(H1N1)pdm09, hospitalizations of children with asthma increase, but they were least often to be ventilated during their pediatric intensive care stay.2) The value of vaccination against the pandemic virus to reduce the use of assisted ventilation in children hospitalized in Pediatric Intensive Care Unit.3) Canada did not experience a third pandemic wave in 2010 because of a massive vaccination campaign that, even late, was effective one year later.4) The bronchiolitis season in the tropics is different from what we know in temperate countries. It is mandatory to adjust management recommendations in the light of regional data.By describing the kinetics and impact of the 2009 influenza pandemic on children in pediatric intensive care in Canada from October 2009 to March 2011, comparing this cohort to a similar cohort in France, and comparing 2 epidemics of VRS in Martinique (French West Indies) in 2007 and 2008 with those that have been carried out in temperate countries, this thesis is an example why we have to constantly question our knowledge because of climate change, change in society and medical knowledge evolution.
32

Influência de sistemas de manejo na produção e nas reservas de pessegueiro precoce (Prunus pérsica (L.) Batsch.) cultivado em clima tropical. / Influence of systems of handling in the production and in the reservations of precocious peach tree (Prunus pérsica (L.) Batsch.) cultivated in tropical climate.

Araujo, João Paulo Campos de 12 January 2005 (has links)
A precocidade de maturação é o principal fator de sucesso econômico do persicultor paulista, em vista desse fato existe uma demanda muito grande por novas técnicas que possibilitem a melhoria da qualidade dos frutos e uma maior precocidade na colheita. Este trabalho visa verificar a influência dos sistemas de podas e manutenção das folhas após a colheita nas reservas de carboidratos não estruturados em ramos e raízes do pessegueiro da cultivar Flordaprince,verificar a produção dessas plantas e a qualidade dos frutos em função das reservase verificar a eficiência do uso do regulador vegetal 2,4-DP (ácido diclofenoxipropiônico), em função das reservas de carboidratos solúveis existentes nas plantas, bem como seu possível efeito na qualidade dos frutos obtidos. O trabalho conduzido na Escola Superior de Agricultura "Luiz de Queiroz", em Piracicaba. O delineamento foi de blocos ao acaso, constando de 9 tratamentos e 4 repetições. Cada parcela foi composta por 4 plantas. Os dados foram submetidos as análises de variância e à comparação das médias pelo Teste de Tukey. O espaçamento adotado foi de 3,0 X 1,2 metros, correspondendo a 2777 plantas ha-1. As plantas foram conduzidas em sistema líder central, e todas receberam as práticas de irrigação, nutrição, quebra de dormência, tratamento fitossanitários, desbrotas, normalmente utilizadas. As podas foram realizadas logo após a colheita, no final de agosto de 2003, quando da ocasião da instalação do experimento. Foram coletadas amostras de raízes e ramos,que foram trituradas, secas em estufas, moídas e submetidas à análise de laboratório. Verificou-se os teores de carboidratos solúveis totais no ramo e na raiz das plantas de pessegueiro. O crescimento dos frutos apresentou a forma de uma curva sigmóide dupla. O tratamento onde não ocorreu desfolha de verão apresentou maior produção de frutos, e maior número de frutos por planta. A aplicação do regulador vegetal 2,4-DP não promoveu aumento significativo nas dimensões dos frutos, causou ainda uma queda no teor de sólidos solúveis e promoveu uma melhora na coloração dos frutos, tanto na face exposta como no fundo do fruto. Ocorreu ainda uma antecipação na colheita em cerda de 7 dias devido a aplicação do regulador vegetal. A concentração de carboidratos solúveis nas raízes e nos ramos flutuou de acordo com a época em que foram coletados, dentro do ciclo da planta, e a concentração nas raízes foi sempre superior àquela encontrada nos ramos. A poda de renovação causou uma queda na produção e um número menor de frutos por planta. / The precocity maturation is the main factor of economical success of the producing of peach from São Paulo, in view of that fact the very big demand exists goes new techniques that make possible the improvement of the quality of the fruits and the larger precocity in the crop. This work seeks to verify the influence of the systems of prunings and maintenance of the leaves after the crop in the carboidrates reservations in the structured in branches and roots of the peach tree of cultivating Flordaprince, to verify the production of those plants and the quality of the fruits in function of the reservations to verify the efficiency of the use of the vegetable regulator 2,4-DP (acid diclofenoxipropiônico), in function of the reservations of existent soluble carboidrates in the plants, as well it’s possible effect in the quality of the obtained fruits. The work was established at Escola Superior de Agricultura "Luiz of Queiroz", in Piracicaba. The experimental design used was of blocks at random, consisting of 9 treatments and 4 repetitions. Each portion was composed by 4 plants. The data were submitted the variance analyses and to the comparison of the averages for the Test of Tukey. The adopted spacing was of 3,0 X 1,2 meters, corresponding to 2777 plants hectare-1. The plants were driven in system central leader, and all received the irrigation practices, nutrition, numbness break, and treatments to keep healthy plants were maid, sprouts were removed, usually used. The prunings were accomplished soon after the crop, in the end of August of 2003, when of the occasion of the installation of the experiment. Samples of roots and branches, that were collected were triturated, droughts in greenhouses, milled and submitted to the laboratory analysis. It was verified the tenors of total soluble carboidrates in the branch and in the root of the peach tree plants. The growth of the fruits presented the form of a curve double sigmóide. The treatment where didn't happen defoliates of summer presented larger production of fruits, and larger number of fruits for plant. The application of the vegetable regulator 2,4-DP didn't promote significant increase in the dimensions of the fruits, it still caused a fall in the tenor of soluble solids and it promoted an improvement in the coloration of the fruits, in the exposed face and in the bottom of the fruit. It still happened an anticipation in the crop in bristle of 7 days due to application of the vegetable regulator. The concentration of soluble carboidrates in the roots and in the branches it floated in agreement with the time in that they were collected, inside of the cycle of the plant, and the concentration in the roots was always superior that found in the branches. The renewal pruning caused a fall in the production and a smaller number of fruits for plant.
33

Modelling of the nitrogen budget of oil palm plantations to help reduce losses to the environment. Case study in Sumatra, Indonesia / Modélisation du bilan azoté des plantations de palmiers à huile pour aider à la réduction des pertes dans l’environnement. Etude de cas à Sumatra, Indonésie.

Pardon, Lénaïc 20 October 2017 (has links)
L’humanité fait face aux défis urgents de réduire l’impact environnemental de l’agriculture, de changer les régimes alimentaires et d’accroître la production alimentaire. Le palmier à huile est une plante pérenne tropicale emblématique de ces défis. Alors que sa culture peut être à l’origine d’impacts environnementaux, le palmier à huile peut produire, en conditions optimales, 7 à 10 fois plus d’huile alimentaire que les cultures oléagineuses annuelles. Dans ce contexte, améliorer la durabilité de la production d’huile de palme est crucial, tant pour réduire les impacts environnementaux négatifs que pour garantir la sécurité alimentaire. L’application de fertilisants azotés (N) a été identifiée comme une source majeure d’impacts environnementaux dus à la culture du palmier. Des analyses de cycle de vie de l’huile de palme ont été réalisées pour quantifier les impacts et identifier des améliorations de pratiques agricoles. Cependant, les seuls modèles d’émissions disponibles pour estimer les pertes de N dans l’environnement sont généralement valides pour les cultures annuelles et en climat tempéré. L’utilisation de tels modèles dans l’analyse de cycle de vie peut mener à des résultats très incertains ou à une faible sensibilité aux pratiques. L’objectif global de ce travail de recherche était d’aider à l’identification de pratiques pour réduire les pertes de N dans l’environnement. Le cœur du travail était le développement d’un modèle estimant toutes les pertes de N dans les plantations, tout en étant sensible aux pratiques. L’étude s’est concentrée sur les flux de N dans les plantations de palmiers sur sols minéraux. Nous avons réalisé quatre étapes pour mener à bien cette recherche. Premièrement, nous avons mené une revue de littérature de tout le savoir existant concernant les flux et pertes de N dans les plantations. Deuxièmement, nous avons comparé 11 modèles existants, pouvant être utilisés pour prédire les pertes de N dans les plantations. Troisièmement, nous avons réalisé une analyse de sensibilité de Morris approfondie du modèle mécaniste APSIM-Oil palm. Quatrièmement, nous avons construit IN-Palm, un indicateur agri-environnemental pour les pertes de N dans les plantations. Nous avons utilisé la méthode INDIGO® et l’approche de modélisation par arbres de décisions flous pour développer IN-Palm, et nous avons validé cet indicateur en utilisant des mesures de lixiviation de N d’une plantation à Sumatra, Indonésie. Notre revue de littérature et notre comparaison de modèles ont montré que les particularités du palmier à huile peuvent affecter significativement les dynamiques et pertes de N. Nous avons identifié des manques de recherche et des incertitudes sur les pertes de N, leurs déterminants et la modélisation des particularités du palmier. Nous avons identifié les déterminants des pertes de N et du rendement dans le modèle mécaniste APSIM-Oil palm. Nous avons développé IN-Palm, qui utilise 21 variables d’entré facilement accessibles pour estimer chaque voie de perte de N. Les prédictions de lixiviation de N par IN-Palm étaient acceptables, et IN-Palm s’est montré efficace pour tester des changements de pratiques agricoles. Cette recherche constitue une synthèse exhaustive des connaissances et modèles disponibles pour les flux et pertes de N dans les plantations. L’un des principaux résultats est un nouvel indicateur agri-environnemental, IN-Palm, sensible aux pratiques et conditions locales, de même qu’utilisable en tant que modèle d’émission dans des approches holistiques. Cet indicateur peut être une base utile pour de futures recherches sur l’utilisation d’indicateurs agri-environnementaux pour réduire l’incertitude des analyses cycle de vie, et pour de futures adaptations à d’autres plantes pérennes tropicales. / Humanity faces the challenges of urgently decreasing the environmental impact of agriculture, shifting diets and increasing food production. Oil palm is a tropical perennial crop emblematic of these challenges. While its cultivation can be associated with environmental impacts, oil palm can produce 3 to 7 t of edible oil ha-1 in optimal conditions, which is 7 to 10 fold higher than in annual oil crops. In this context, improving palm oil production sustainability is crucial for both reducing negative environmental impacts and ensuring food security. Application of synthetic nitrogen (N) fertilisers was identified as a major source of environmental impacts associated with the cultivation of oil palm. Life cycle assessments of palm oil have already been performed to help quantify impacts and identify potential improvements of management practices. However, the only available emission models to estimate N losses to environment are generally valid for annual crops and temperate climate conditions. The use of such general models in life cycle assessment may lead to very uncertain results or to low sensitivity of assessments to management practices. The overall objective of this research work was to help identify management practices to reduce N losses in the environment. The core of the work was hence to develop a model that estimates all N losses in oil palm plantations, while being sensitive to management practices. The study focused on N fluxes in industrial oil palm plantations on mineral soils. We performed four steps in order to complete the objectives of this research work. First, we conducted a literature review of all the existing knowledge about N fluxes and losses in plantations. Second, we compared 11 existing models that may be used to predict N losses in plantations. Third, we performed an in-depth Morris’s sensitivity analysis of one of the models, the APSIM-Oil palm process-based model. Fourth, we used all the information identified in the previous chapters, together with expert knowledge, to build IN-Palm, an agri-environmental indicator for N losses in oil palm plantations. We used the INDIGO® method and the fuzzy decision tree modelling approach to develop IN-Palm, and we validated this indicator using a field dataset of N leaching from a plantation in Sumatra, Indonesia. Our literature review and model comparison showed that oil palm peculiarities may impact significantly N dynamics and losses. We identified research gaps and uncertainties about N losses, their drivers and the modelling of oil palm peculiarities. We identified the main drivers of N losses and yield in the APSIM-Oil palm processbased model. We built IN-Palm, which uses 21 readily available input variables to estimate each N loss pathway. IN-Palm predictions of N leaching were acceptable, and IN-Palm has shown efficient to help testing management changes. This research constitutes a comprehensive synthesis of the available knowledge and models for N fluxes and losses in oil palm plantations. One of the main results is a novel agri-environmental indicator, IN-Palm, operationally-oriented, sensitive to local practices and environmental conditions, as well as potentially useable as an emission model for holistic approaches such as life cycle assessment. The INDIGO® method and fuzzy decision tree modelling approach were shown to be very well adapted for building agri-environmental indicators in contexts of knowledge scarcity. This indicator can be a useful base for further research about using agrienvironmental indicators to reduce uncertainty in life cycle assessment, and for future adaptations for other tropical perennial crops.
34

Analyse du retour d'expérience et optimisation de la recherche opérationnelle maîtrise d'ouvrage pour les quartiers durables en milieu tropical / Analysis of feedback and optimization of operational research project management for sustainable neighborhoods in tropical environment

Riviere, Pierre-Alexandre 03 November 2017 (has links)
L’application du concept de développement durable à l’urbanisme suscite de nombreuses questions tant les contours de « l’urbanisme durable » et des « quartiers durables » paraissent flous. De nombreux outils ont été développés pour aider à la conception des « quartiers durables », souvent dérivés des outils de conception des bâtiments (LEED, BREAAM, HQE etc…) ; ils restent largement proposés et conduis par les Maîtres d’Oeuvre (MOE) et les Assistants à Maîtrise d’Ouvrage (AMO). Dans ce contexte, une question émerge, celle de savoir quel peut-être l’impact de ces outils sur les décisions et la conduite du projet urbain par la Maîtrise d’Ouvrage Urbaine (MOU). De plus, le projet urbain qui a pour objet la création d’un quartier ou « morceau de ville », fait appel à un large jeu d’acteurs et les questions soulevées par les outils d’aide à la conception dépassent largement le champ d’action de la MOU. Ceci posé, si le couple MOE et AMO peut « se contenter » de l’utilisation d’outils existants au regard de leurs missions respectives, la MOU, du fait de son rôle central et moteur dans le « quartier durable » a de son côté besoin de nouveaux process pour répondre aux enjeux de la durabilité posés par ces outils : comment travailler avec les différents acteurs en vue d’objectifs communs et/ou convergeants ? Se pose alors la problématique de l’évolution des méthodes de travail de la MOU au fil des opérations d’aménagement durable ; comment ne pas avoir de « pertes en ligne » et ainsi continuer à progresser entre deux opérations d’aménagements : la capitalisation des savoir-faire du « chef d’orchestre » qu’est la MOU est alors un questionnement central. / The application of the concept of sustainable development to urban planning raises many questions as the contours of "sustainable urbanism" and "sustainable neighborhoods" appear to be unclear. Many tools have been developed to help design "sustainable neighborhoods", often derived from building design tools (LEED, BREAAM, HQE etc ...); they remain largely proposed and led by the Project Managers (MOE) and the Assistants to Project Managers (AMO). In this context, a question arises, which is to know what may be the impact of these tools on the decisions and the conduct of the urban project by the Urban Contractor (MOU). In addition, the urban project, which aims to create a neighborhood or "piece of town", involves a wide range of actors and the questions raised by the Neighborhood Sustainable Assement (NSA) go well beyond the scope of action of the MOU. If the MOE and AMO couple can "be satisfied" using the existing tools regarding their respective missions; the MOU, because of its central role and driving force in the "sustainable neighborhood" is in need of new processes to meet the challenges of sustainability requested by these tools: how to work with the different actors aiming a shared vision with common and / or converging objectives? Then naturaly the problem of the evolution of the working methods of the MOU is posed: during the conduct of the neighborhood development, how not to have "losses online" and thus continue to progress between two neighborhood development: the capitalization of the know-how of the MOU starts to become the central question.
35

Influência de sistemas de manejo na produção e nas reservas de pessegueiro precoce (Prunus pérsica (L.) Batsch.) cultivado em clima tropical. / Influence of systems of handling in the production and in the reservations of precocious peach tree (Prunus pérsica (L.) Batsch.) cultivated in tropical climate.

João Paulo Campos de Araujo 12 January 2005 (has links)
A precocidade de maturação é o principal fator de sucesso econômico do persicultor paulista, em vista desse fato existe uma demanda muito grande por novas técnicas que possibilitem a melhoria da qualidade dos frutos e uma maior precocidade na colheita. Este trabalho visa verificar a influência dos sistemas de podas e manutenção das folhas após a colheita nas reservas de carboidratos não estruturados em ramos e raízes do pessegueiro da cultivar Flordaprince,verificar a produção dessas plantas e a qualidade dos frutos em função das reservase verificar a eficiência do uso do regulador vegetal 2,4-DP (ácido diclofenoxipropiônico), em função das reservas de carboidratos solúveis existentes nas plantas, bem como seu possível efeito na qualidade dos frutos obtidos. O trabalho conduzido na Escola Superior de Agricultura “Luiz de Queiroz”, em Piracicaba. O delineamento foi de blocos ao acaso, constando de 9 tratamentos e 4 repetições. Cada parcela foi composta por 4 plantas. Os dados foram submetidos as análises de variância e à comparação das médias pelo Teste de Tukey. O espaçamento adotado foi de 3,0 X 1,2 metros, correspondendo a 2777 plantas ha-1. As plantas foram conduzidas em sistema líder central, e todas receberam as práticas de irrigação, nutrição, quebra de dormência, tratamento fitossanitários, desbrotas, normalmente utilizadas. As podas foram realizadas logo após a colheita, no final de agosto de 2003, quando da ocasião da instalação do experimento. Foram coletadas amostras de raízes e ramos,que foram trituradas, secas em estufas, moídas e submetidas à análise de laboratório. Verificou-se os teores de carboidratos solúveis totais no ramo e na raiz das plantas de pessegueiro. O crescimento dos frutos apresentou a forma de uma curva sigmóide dupla. O tratamento onde não ocorreu desfolha de verão apresentou maior produção de frutos, e maior número de frutos por planta. A aplicação do regulador vegetal 2,4-DP não promoveu aumento significativo nas dimensões dos frutos, causou ainda uma queda no teor de sólidos solúveis e promoveu uma melhora na coloração dos frutos, tanto na face exposta como no fundo do fruto. Ocorreu ainda uma antecipação na colheita em cerda de 7 dias devido a aplicação do regulador vegetal. A concentração de carboidratos solúveis nas raízes e nos ramos flutuou de acordo com a época em que foram coletados, dentro do ciclo da planta, e a concentração nas raízes foi sempre superior àquela encontrada nos ramos. A poda de renovação causou uma queda na produção e um número menor de frutos por planta. / The precocity maturation is the main factor of economical success of the producing of peach from São Paulo, in view of that fact the very big demand exists goes new techniques that make possible the improvement of the quality of the fruits and the larger precocity in the crop. This work seeks to verify the influence of the systems of prunings and maintenance of the leaves after the crop in the carboidrates reservations in the structured in branches and roots of the peach tree of cultivating Flordaprince, to verify the production of those plants and the quality of the fruits in function of the reservations to verify the efficiency of the use of the vegetable regulator 2,4-DP (acid diclofenoxipropiônico), in function of the reservations of existent soluble carboidrates in the plants, as well it’s possible effect in the quality of the obtained fruits. The work was established at Escola Superior de Agricultura “Luiz of Queiroz”, in Piracicaba. The experimental design used was of blocks at random, consisting of 9 treatments and 4 repetitions. Each portion was composed by 4 plants. The data were submitted the variance analyses and to the comparison of the averages for the Test of Tukey. The adopted spacing was of 3,0 X 1,2 meters, corresponding to 2777 plants hectare-1. The plants were driven in system central leader, and all received the irrigation practices, nutrition, numbness break, and treatments to keep healthy plants were maid, sprouts were removed, usually used. The prunings were accomplished soon after the crop, in the end of August of 2003, when of the occasion of the installation of the experiment. Samples of roots and branches, that were collected were triturated, droughts in greenhouses, milled and submitted to the laboratory analysis. It was verified the tenors of total soluble carboidrates in the branch and in the root of the peach tree plants. The growth of the fruits presented the form of a curve double sigmóide. The treatment where didn't happen defoliates of summer presented larger production of fruits, and larger number of fruits for plant. The application of the vegetable regulator 2,4-DP didn't promote significant increase in the dimensions of the fruits, it still caused a fall in the tenor of soluble solids and it promoted an improvement in the coloration of the fruits, in the exposed face and in the bottom of the fruit. It still happened an anticipation in the crop in bristle of 7 days due to application of the vegetable regulator. The concentration of soluble carboidrates in the roots and in the branches it floated in agreement with the time in that they were collected, inside of the cycle of the plant, and the concentration in the roots was always superior that found in the branches. The renewal pruning caused a fall in the production and a smaller number of fruits for plant.
36

Des contraintes solaires à des opportunités de projet urbain : optimisation de typomorphologies urbaines en climat tropical au Brésil / From solar constraints to urban design opportunities : optimization of urban typologies in tropical city in brazil / De condicionantes solares à oportunidades de desenho urbano : optimizaçao de tipo-morfologias urbanas em contexto de clima tropical

Agra de Lemos Martins, Tathiane 31 March 2014 (has links)
Environ trois quarts des ressources globales sont aujourd'hui consommés dans les aires urbaines. Le processus d'urbanisation induit des changements sévères du climat local, de la qualité environnementale des espaces, ainsi qu'une augmentation significative de la demande énergétique des bâtiments. Les projections statistiques sur la croissance de la population urbaine indiquent que cette situation tendra à s'aggraver dans les années à venir. Il devient donc impératif de chercher d'autres stratégies pour mieux adapter les environnements urbains aux nouvelles demandes énergétiques, afin de réduire l'empreinte environnementale des villes. Dans ce contexte, ce travail est une contribution à la recherche énergétique urbaine, plus particulièrement en ce qui concerne l'énergie consommée et potentiellement produite parles bâtiments à l'échelle urbaine locale. La morphologie urbaine est ici considérée comme un paramètre crucial dans le processus d'amélioration de l'efficacité énergétique du cadre bâti. Dans les zones de basses latitudes, sous climat tropical, l'énergie solaire incidente est extrêmement abondante. Toutefois, la bonne utilisation de cette ressource dans les bâtiments peut suggérer l'adoption de formes urbaines très peu denses et étales, en vue de réduire les obstructions produites par l'environnement proche. A rebours, ces formes urbaines très peu denses peuvent entrainer une augmentation des apports solaires sur les façades,élevant la demande énergétique. Le contrôle des gains solaires sur les façades pour la réduction de la demande énergétique peut ainsi représenter une perte potentielle en terme d'éclairement naturel des espaces, et une réduction du potentiel de production d'énergie solaire. Afin de quantifier le potentiel de ces stratégies conflictuelles, il devient indispensable de convoquer des modèles d'analyse pluridisciplinaires, permettant de mettre en oeuvre des approches multicritères dans le processus de conception de la forme urbaine. Cette thèse s'appuie sur une réflexion prospective sur les quartiers de la ville de Maceió, Alagoas, au Brésil. Dans un premier temps, un ensemble de paramètres morphologiques caractéristiques sont employés pour identifier et caractériser le potentiel solaire de typologies de référence de la ville. Ensuite, ces paramètres sont soumis à une analyse de sensibilité via un plan d'expérience. Les paramètres statistiquement significatifs sont alors intégrés à une méthode paramétrique d'optimisation dans laquelle l'algorithme génétique NSGA-II est couplé à un algorithme simplifiée de radiosité, visant à maximiser le potentiel de production d'énergie sur les toitures des bâtiments, tout en minimisant les apports solaires sur ses façades. Nous considérons des seuils d'éclairement naturel et intégrons des règles locales d'urbanisme comme contraintes aux projets. Cinq typologies représentatives du tissu urbain de Maceió ont ainsi été identifiées. L'ensemble des indicateurs les plus influents sur le potentiel solaire des formes urbaines a été hiérarchisé, en mettant l'accent notamment sur le rôle du prospect moyen ou de l'albédo des surfaces. La méthode d'optimisation a permis de tester plus de 80 000configurations d'ilots urbains et les résultats obtenus font apparaître une grande diversité de morphologies «optimum». Ces projets ont des performances solaires supérieures à celles des typologies existantes dans la ville. Cette intégration de stratégies énergétiques contradictoires montre qu'au-delà de l'intégration de contraintes variées et d'une meilleure adaptation à la complexité du processus de design urbain, l'approche utilisée ici apparaît très utile pour la recherche de solutions urbaines performantes à l'échelle des quartiers. Cette approche peut ainsi participer au renouvellement de l'Architecture de la Ville / At the beginning of 21th century, the world was faced with unprecedented environmental transformations. The urbanization process reached record levels and it keeps increasing, especiallyin developing countries. Around 3/4 of global resources are currently consumed in urban settlements, with corresponding adverse environmental consequences which leads to severe local climate changes, affecting environmental quality of spaces and leading to a significant increase of energy demand in buildings. A projection of the world urban population indicates that this situation will worsen in the coming years. It is therefore imperative that we understand how to design less resource intensive urban settlements. This research consists of a contribution to the energy debate in cities, focusing on the energy potentially consumed and produced by the built environment in the neighborhood scale. Urban morphology has been pointed out as a pivotal issue on shifting to climate adapted urban environments towards energy efficiency of buildings. In tropical climate regions, solar energy represents a high potential for renewable electric production in buildings, recording high levels of irradiation throughout the year. Though, engaging such a strategy may suggest applying sparsely low-density urban forms, aiming at reducing obstructions caused by the urban built surroundings. On one hand, scattered and less dense urban forms may result in significant increase of solar thermal load in buildings vertical facades, but on the other hand, the control of the solar heat gains in urban facades may represent significant losses on indoors daylight levels andalso reducing solar energy harness. Estimating the relative potential of these conflicting design strategies, taking into account the constrained parameters related to local building regulation, requires coupling multidisciplinary and multiobjective models of analysis in order to integrate multi-criteria approach in the urban design process. This thesis aims to contribute to a prospective energy debate toward sustainable urban districts for the city of Maceió in Brazil. Firstly, a set of energy-related morphological parameters are applied to identify, classify and characterize the solarpotential of local urban typologies. Then, these parameters are analyzed by means of a sensitivity analysis using a design of experiments reduced factorial method. The statistically most significant parameters are then submitted to a parametric design methodology via optimization, in which thenon-dominated sorting genetic algorithm (NSGA-II) is coupled with a simplified radiosity algorithm.The solar constraints are integrated as design criteria aiming at maximizing the solar energy potential on building roofs and minimizing solar gains on the their vertical facades. Daylight threshold levels as well as local building regulation parameters are taken into account as design constraints. Five representative types of urban fabric of Maceió were identified which allowed examining and adapting them from the use of energy-related indicators of the urban form. A set of most influential indicators of solar potential of urban forms was hierarchized, highlighting the role of the aspect ratio and albedo of urban surfaces. The application of optimization algorithm allowed testing more than 80,000 urban settings, pointing out a great diversity of "optimum" morphologies of urban blocks. The urban block designs obtained behaved better compared to the existing local typologies. Dealing with conflicting energy strategies by means of a constrained evolutionary optimization design process offered a great opportunity in searching for new solutions to the urban design in the neighborhood scale, helping to guide urban designers' decisions and allowing arenewal of the Architecture of the city
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Molecular epidemiology of epidemic severe malaria caused by Plasmodium vivax in the state of Amazonas, Brazil /

Santos-Ciminera, Patricia Dantas. Ciminera, Patricia Dantas Santos. Santos, Patricia. January 2005 (has links) (PDF)
Thesis (Ph. D.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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Evaluation of Crop Water Use and Rice Yield Using Remote Sensing and AquaCrop Model for Three Irrigation Schemes in Sri Lanka

Widengren, Veronika January 2022 (has links)
With a changing climate and an increased competition over water resources for agricultural irrigation, the need to improve crop water productivity using time and cost-efficient methodologies have become critically important. The Malwathu Oya river basin in Sri Lanka is struggling with water scarcity, which threatens food security and the income of farmers. In this study, freely available remote sensed land- and water productivity data from FAO’s WaPOR database was evaluated. The evaluation consisted of a comparison of the WaPOR data and primary collected field data using the crop water model, AquaCrop, for three irrigation schemes in the Malwathu Oya river basin. Additionally, the spatio-temporal variability in crop water use within and across these three irrigation schemes was assessed using indicators derived from the WaPOR portal. The evaluation was conducted for the main cultivation season, called Maha, between 2010 and 2021.  The WaPOR and AquaCrop actual evapotranspiration (ETa) values were found to be in relatively good agreement (312–537 and 400–465 mm respectively). WaPOR yield values (2.5–2.9 ton/ha) were however lower compared to the AquaCrop simulated yield values and historical yield data (4.6–5.7 and 4.4–5.6 ton/ha respectively). Difference in calculation methodology, possible sources of error in WaPOR conversion calculations and limitations in accuracy caused by cloud coverage when collecting satellite data could be explanations for this. Prior knowledge and accurate allocation of the crop type and parameters used in conversion calculations in WaPOR is therefore of significant influence. From the spatio-temporal variation assessment with WaPOR indicators, a fair uniformity of the water distribution within the irrigation schemes was shown (CV 11–19 %). The beneficial water use (BWU) in the irrigation schemes showed lower values (50–90 % allocated to T) for years when the available water amount was higher, which could be explained by the higher rate of water lost through soil evaporation. Crop water productivity (CWP) values showed higher values (about 0.70 kgDM/m3) when the available water amount was higher, indicating that yield production is sensitive to water-scarce environments. Applying a yield boundary function, representing the best attainable yield in relation to water resource, showed that there is potential to achieve the same yield with less amount of water. There are thus possibilities for improved water productivity in the three irrigation schemes investigated. For future research it is recommended to perform a sensitivity analysis for WaPOR and ground truth with yield data to obtain a better understanding of potential limitations. To obtain more precise site descriptions it is also recommended to ground truth AquaCrop with yield and soil data.

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