Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-10-05T21:25:00Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Alejandro Caballero Rivero.pdf: 2100591 bytes, checksum: 62dd204ed9c731cf36a92609d07d3461 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-11-22T19:25:33Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Alejandro Caballero Rivero.pdf: 2100591 bytes, checksum: 62dd204ed9c731cf36a92609d07d3461 (MD5) / Made available in DSpace on 2018-11-22T19:25:33Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Alejandro Caballero Rivero.pdf: 2100591 bytes, checksum: 62dd204ed9c731cf36a92609d07d3461 (MD5) Previous issue date: 2017-07-25 / CAPES / O objetivo da pesquisa é caracterizar as práticas de publicação das grandes áreas do conhecimento no Brasil no período 2000 – 2014. Considera-se que os sistemas de avaliação da pesquisa no Brasil, dando preponderância aos indicadores de artigos publicados em periódicos sobre outros canais de comunicação, não consideram adequadamente as diferenças nas práticas de publicação das grandes áreas do conhecimento. Metodologicamente a pesquisa insere-se no contexto das Ciências Sociais e assumem-se os processos de geração, produção e disseminação do conhecimento científico como processos sociais e, portanto, complexos e multidimensionais. Utiliza-se o Modelo Ampliado de Análise Dimensional para a construção das dimensões epistemológica, teórica, técnica, morfológica, ética e política da pesquisa. O discurso tem como base a lógica da quantificação como modo de raciocínio nas Ciências Sociais; o positivismo e o funcionalismo como quadros de referência dos estudos cienciométricos; a concepção Mertoniana da ciência como uma instituição social que precisa ser avaliada; a noção das comunidades acadêmicas como detentoras de culturas epistêmicas que conformam diferentes práticas de publicação e a crítica ao uso de indicadores quantitativos produzidos por empresas privadas do hemisfério norte para avaliar a pesquisa no Brasil. Se realiza uma revisão de literatura a partir de artigos, livros e trabalhos em anais de eventos prospectados das bases de dados da Web of Science, Scopus e SciELO. Os dados da produção científica dos pesquisadores doutores brasileiros são coletados a partir do Diretório de Grupos de Pesquisa do CNPq, considerando os artigos em periódicos nacionais e internacionais, os livros, os capítulos de livros e os trabalhos em anais de eventos. Definem-se os indicadores de análise, constroem-se e representam-se graficamente as séries históricas dos indicadores, identificam-se padrões e realizam-se as análises correspondentes. As análises realizadas permitiram identificar os canais de comunicação predominantes: artigos nacionais, trabalhos em anais e capítulos de livros nas Ciências Humanas, Sociais Aplicadas e Linguística, Letras e Artes; artigos internacionais nas Ciências Exatas e da Terra e Biológicas, artigos internacionais e nacionais nas Ciências Agrárias e da Saúde e os trabalhos em anais nas Engenharias e Ciência da Computação. Corrobora-se a existência de duas hiper-áreas que compartilham padrões nas práticas de publicação: ciências “duras” (Engenharias e Ciência da Computação, Ciências Exatas e da Terra, Agrarias, Biológicas e da Saúde) e Humanidades (Ciências Sociais Aplicadas, Humanas e Linguística, Letras e Artes). A comparação desses padrões mostra que nas ciências “duras” predomina claramente a publicação de artigos se comparada com as monografias e os artigos mostram uma orientação majoritariamente internacional. Nas Humanidades manifesta-se um equilíbrio entre a publicação de artigos, monografias e trabalhos em anais e os artigos mostram uma orientação predominantemente nacional. Verificam-se mudanças nas práticas de publicação das ciências “duras”: a publicação de trabalhos em anais decresce ao longo do tempo; nas Ciências da Saúde a orientação da produção de artigos passou de ser majoritariamente nacional para internacional; nas Ciências Agrarias essa mudança está em processo. Os resultados fornecem elementos para o uso de critérios diferenciados para a avaliação da pesquisa das grandes áreas do conhecimento. / The aim of this work is to characterize the publication practices of the broad disciplinary areas of knowledge in Brazil during the 2000–2014 period. It is considered that the research evalution system in Brazil, giving preponderance to the indicators of articles published in journals over other communication channels, does not adequately considers the differences in the publishing practices of broad disciplinary areas of knowlege. Methodologically, the research is inserted in the field of the Social Sciences, therefore, processes of generation, production and dissemination of scientific knowledge are assumed as complex and multidimensional social processes. The Extended Model of Dimensional Analysis is used for the construction of the epistemological, theoretical, technical, morphological, ethical and political dimensions of research. The discourse is based on: the logic of quantification as a mode of reasoning in the Social Sciences; Positivism and Functionalism as the reference frames for the scientometric studies; the Mertonian conception of science as a social institution that needs to be evaluated; the notion of academic communities as holders of epistemic cultures that conform different publishing practices; and the criticism to the use of quantitative indicators produced by private companies of the northern hemisphere for research evaluation in Brazil. A review of the literature is performed from articles, books and papers, published in proceedings of conferences collected from the Web of Science, Scopus and SciELO databases. Data on scientific production of the Brazilian PhD researchers is collected from the CNPq Research Groups Directory, considering national and international articles published in journals, books, book chapters, and papers published in conference proceedings. The indicators for analysis were defined, their statistical series agains time were constructed and represented graphically, patterns were identified and examined. The analysis made it possible to identify the predominant communication channels: national articles, papers in proceedings of conferences and book chapters in the Humanities, Applied Social Sciences and Linguistics, Literature and Arts; international and national articles in the Agrarian and Health Sciences, international articles in Biological and Exact and Earth Sciences and papers published in conference proceedings in Engineering and Computing Science. The existence of two hyper-areas sharing patterns in publishing practices were identified: "hard" sciences (Engineering and Computer Science, Exact and Earth Sciences, Agrarian, Biological and Health Sciences) and Humanities (Applied Social Sciences, Humanities And Linguistics, Literature and Arts). The comparison of these patterns shows that in the "hard" sciences, the publication of articles clearly predominates when compared to monographs, and articles show a mainly international orientation. In the Humanities there is a balance between the publication of articles, monographs and papers published in conference proceedings, while articles show predominantly national orientation. Some shifts in the publishing practices of "hard" sciences are verified: the publication of papers in conferences proceedings decreases over time; in the Health Sciences they clearly shift from mainly national production of articles in journals to international; shift tht is still in course in the Agrarian Sciences. The results provide elements for the use of differentiated criteria for research evaluation of large knowledge areas.

A acne vulgar é uma das doenças cutâneas mais comuns, apresentando como um de seus fatores fisiopatológicos primários a colonização pelo microrganismo Propionibacterium acnes. Atualmente, têm-se buscado terapias alternativas para o combate ao P. acnes, destacando-se alguns ácidos graxos, como o ácido laúrico (LA). O LA é uma molécula pouco solúvel em água, sendo possível sua incorporação em lipossomas. Os lipossomas apresentam capacidade de encapsulação/ liberação de ativos e impedem a desidratação da pele, tornando-se ingredientes inovadores na área de cosméticos. Foram preparados lipossomas de dipalmitoilfosfatidilcolina (DPPC) contendo diferentes concentrações de LA, que variaram de 0 a 50% da concentração total em mol, em quatro pHs: 9,0, 7,4, 5,0 e 3,0. Nestes pHs o estado de protonação do LA muda variando de 0 a -1. Os lipossomas foram extrusados por filtros com poros de 100 nm de diâmetro visando à obtenção de vesículas unilamelares grandes (LUV). As LUV foram caracterizadas quanto a sua estabilidade em condições de prateleira, temperatura de transição de fase da bicamada, encapsulamento no interior aquoso, liberação do LA, difusão das vesículas na pele e seus aspectos morfológicos foram caracterizados por espalhamento de raios-X a baixo ângulo (SAXS) e crio-microscopia eletrônica de transmissão. Estudos de estabilidade mostraram que independentemente da concentração de LA, as formulações são mais estáveis em pHs mais altos, quando LA está em sua maioria na forma de laurato. Os experimentos de DSC revelaram que em pHs 3,0 e 5,0 e concentrações maiores de LA, a interação deste ácido graxo com as bicamadas é favorecida, havendo um aumento da temperatura de transição de fase (Tm) e diminuição da cooperatividade. Análises de taxa de incorporação de sondas hidrofílicas confirmaram a presença de um compartimento aquoso interno para as vesículas de DPPC:LA. O LA conseguiu permear a pele no período avaliado e pouco LA foi liberado das vesículas em condições de temperatura ambiente. A morfologia das LUV se mostrou bem diferente da esperada e se observaram vesículas com mais de uma bicamada e outros formatos que não o esférico. Estes resultados podem auxiliar na otimização das condições para uma formulação que poderá ser usada no tratamento da acne, aumentando a eficácia do LA no sítio alvo. / Acne vulgaris is one of the most common skin diseases, presenting as one of its causes the microorganism Propionibacterium acnes colonization. Currently, it has been sought alternatives therapies against P. acnes, especially some fatty acids, like the lauric acid (LA). LA is a molecule with low water solubility, allowing its incorporation in liposomes. Liposomes have encapsulation/release capacity of drugs and promote skin lipids regeneration, becoming an innovative ingredient in cosmetics area. Dipalmitoylphosphatidylcholine (DPPC) vesicles containing different LA concentrations were prepared at pHs: 9.0, 7.4, 5.0 and 3.0. At these pHs the LA protonation changes and its charge varies from 0 to -1. The vesicles were extruded through filters containing pores of 100 nm to obtain large unilamellar vesicles (LUV) that were characterized for stability in shelf conditions, bilayer phase transition temperature, aqueous internal compartment encapsulation, LA release and in vitro skin permeation. Its morphological features were characterized by small angle X-ray scattering (SAXS) and cryo-electron transmission microscopy. Stability assays showed that, regardless LA concentration, formulations were more long-term stable in higher pHs, when LA is mostly in the form of laurate. The differential scanning calorimetry, DSC, experiments showed that, at pHs 3.0 and 5.0 and higher LA concentrations, the interaction between the bilayer and LA is favored, increasing phase transition temperature (Tm) and reducing cooperativity. Incorporation of hydrophilic probes confirmed the presence of an internal aqueous compartment in DPPC:LA vesicles. The LA managed to permeate the skin on the period evaluated and, in ambient conditions, low LA concentration was released from the vesicles. LUV containing more than one bilayer and non-spherical structures were observed. The obtained results may help in the optimization of the conditions for a formulation that can be used in the treatment of acne and improving the effectiveness of LA delivery to the target site.

Magíster en Gestión para la Globalización / Paris, cadena de tiendas por departamento, se plantea la posibilidad de expandir sus operaciones a Colombia, como parte de su estrategia de internacionalización, basándose principalmente en la observación de lo que están haciendo los otros retailers chilenos en Latinoamérica y que se cataliza dada la compra de supermercados Carrefour Colombia por parte de su casa matriz, Cencosud, lo que disponibiliza terrenos para instalarse en ese país. Por lo tanto, el objetivo de este trabajo es realizar una evaluación estratégica y económica de la entrada de Paris al mercado de tiendas por departamento colombiano. En la primera sección de este trabajo se definió a Colombia como el país ideal para continuar con la estrategia de internacionalización de Paris, ya que ofrece una serie de oportunidades e incentivos para la inversión extranjera y porque se encuentra viviendo un proceso de recuperación política y económica que ha atraído a los grandes actores del retail latinoamericano. Las tiendas por departamento son una industria creciente en Colombia, la cual está lejos de saturarse y Paris cuenta con los recursos tanto económicos, de personas y know-how para lograr una expansión exitosa bajo la modalidad Greenfield o de inversión directa. El estudio de mercado muestra que la mejor estrategia es replicar el modelo de negocios que posee la compañía en Chile y realizar pequeñas adaptaciones locales, basándose en la exitosa experiencia que tiene Falabella en ese país. Esto tiene implicancias en el Plan de Marketing y Operaciones, ya que las tiendas funcionarán de una manera muy similar a como operan actualmente en nuestro país, manteniendo el lay-out y el mix de productos. La selección de la localización de las tiendas se realizó seleccionando ciudades donde los segmentos altos son más relevantes y que no sean mercados saturados por los competidores. En esas ciudades, se seleccionaron los locales de Carrefour Colombia que cuenten con cercanía a los estratos objetivos, geo-referenciados a través de la estratificación socioeconómica, el atractivo comercial del área determinado a través del modelo de Huff y la ubicación del establecimiento dentro de un Centro Comercial, lo que entregó las ubicaciones exactas dentro de Bogotá, Medellín, Cali, Barranquilla, Cartagena y Pereira que resultan más atractivas para instalar las tiendas Paris. Por las diferencias entre estas ciudades, la comunicación se debe realizar en dos etapas, primero a nivel local y luego nacional. La operación se realizará con elementos locales en las actividades primarias y el corporativo realizará las de apoyo en la casa matriz. La estructura de Recursos Humanos será liviana, pero con la suficiente independencia que requiera para tomar las decisiones relevantes del negocio a nivel local, con un equipo multinacional, teniendo en cuenta las diferencias culturales entre Chile y Colombia. La evaluación económica mostró que realizar un Greenfield resulta muy conveniente, con un VAN de USD 136 millones, descontado a WACC 10,7%, y una TIR de 24,7%. Finalmente, se recomienda evaluar la expansión a otras ciudades colombianas más pequeñas y también a otras economías latinoamericanas.

Etant donné le coût élevé qui accompagne, en général, la résolution de problème en grandes dimensions, notamment quand il s'agit de problèmes réels; le recours à des fonctions dite benchmarks et une approche communément utilisée pour l'évaluation d'algorithmes avec un coût minime. Il est alors question de savoir identifier les formes par lesquelles ces problèmes se présentent pour pouvoir les reproduire dans ces benchmarks. Une question dont la réponse est difficile vu la variété de ces problèmes, leur complexité, et la difficulté de tous les décrire pertinemment. L'idée est alors d'examiner les difficultés qui accompagnent généralement ces problème, ceci afin de les reproduire dans les fonctions benchmarks et évaluer la capacité des algorithmes à les résoudre. Dans le cas des problèmes de grandes dimensions, il serait pratique de pouvoir simplement étendre les benchmarks déjà utilisés pour les dimensions moins importantes. Cependant, il est important de prendre en compte les contraintes additionnelles qui accompagnent les problèmes de grandes dimensions, notamment ceux liés à la complexité d'évaluer ces fonctions benchmark. Idéalement, les fonctions benchmark en grandes dimension garderaient la majorité des propriétés de leurs contreparties en dimensions réduite tout en ayant un coût raisonnable. Les problèmes benchmark sont souvent classifiés en catégories suivant les difficultés qu'ils présentent. Même dans un scénario en boîte-noire où ce genre d'information n'est pas partagée avec l'algorithme, il reste important et pertinent d'avoir cette classification. Ceci permet d'identifier les lacunes d'un algorithme vis à vis d'une difficulté en particulier, et donc de plus facilement pouvoir l'améliorer. Une autre question importante à se poser en modélisant des problèmes de grandes dimensions est la pertinence des variables. En effet, quand la dimension est relativement petite, il n'est pas rare de voir toutes les variables contribuer à définir la qualité d'une solution. Cependant, quand la dimension grandit, il arrive souvent que des variables deviennent redondantes voire inutiles; notamment vu la difficulté de trouver une représentation minimaliste du problème. Ce dernier point encourage la conception et d'algorithmes et de fonctions benchmark traitant cette classe de problèmes. Dans cette thèse, on répond, principalement, à trois questions rencontrées dans l'optimisation stochastique continue en grandes dimensions : 1. Comment concevoir une méthode d'adaptation du pas d'une stratégie d'évolution qui, à la fois, est efficace et a un coût en calculs raisonnable ? 2. Comment construire et généraliser des fonctions à faible dimension effective ? 3. Comment étendre un ensemble de fonctions benchmarks pour des cas de grandes dimensions en préservant leurs propriétés sans avoir des caractéristiques qui soient exploitables ? / Because of the generally high computational costs that come with large-scale problems, more so on real world problems, the use of benchmarks is a common practice in algorithm design, algorithm tuning or algorithm choice/evaluation. The question is then the forms in which these real-world problems come. Answering this question is generally hard due to the variety of these problems and the tediousness of describing each of them. Instead, one can investigate the commonly encountered difficulties when solving continuous optimization problems. Once the difficulties identified, one can construct relevant benchmark functions that reproduce these difficulties and allow assessing the ability of algorithms to solve them. In the case of large-scale benchmarking, it would be natural and convenient to build on the work that was already done on smaller dimensions, and be able to extend it to larger ones. When doing so, we must take into account the added constraints that come with a large-scale scenario. We need to be able to reproduce, as much as possible, the effects and properties of any part of the benchmark that needs to be replaced or adapted for large-scales. This is done in order for the new benchmarks to remain relevant. It is common to classify the problems, and thus the benchmarks, according to the difficulties they present and properties they possess. It is true that in a black-box scenario, such information (difficulties, properties...) is supposed unknown to the algorithm. However, in a benchmarking setting, this classification becomes important and allows to better identify and understand the shortcomings of a method, and thus make it easier to improve it or alternatively to switch to a more efficient one (one needs to make sure the algorithms are exploiting this knowledge when solving the problems). Thus the importance of identifying the difficulties and properties of the problems of a benchmarking suite and, in our case, preserving them. One other question that rises particularly when dealing with large-scale problems is the relevance of the decision variables. In a small dimension problem, it is common to have all variable contribute a fair amount to the fitness value of the solution or, at least, to be in a scenario where all variables need to be optimized in order to reach high quality solutions. This is however not always the case in large-scales; with the increasing number of variables, some of them become redundant or groups of variables can be replaced with smaller groups since it is then increasingly difficult to find a minimalistic representation of a problem. This minimalistic representation is sometimes not even desired, for example when it makes the resulting problem more complex and the trade-off with the increase in number of variables is not favorable, or larger numbers of variables and different representations of the same features within a same problem allow a better exploration. This encourages the design of both algorithms and benchmarks for this class of problems, especially if such algorithms can take advantage of the low effective dimensionality of the problems, or, in a complete black-box scenario, cost little to test for it (low effective dimension) and optimize assuming a small effective dimension. In this thesis, we address three questions that generally arise in stochastic continuous black-box optimization and benchmarking in high dimensions: 1. How to design cheap and yet efficient step-size adaptation mechanism for evolution strategies? 2. How to construct and generalize low effective dimension problems? 3. How to extend a low/medium dimension benchmark to large dimensions while remaining computationally reasonable, non-trivial and preserving the properties of the original problem?

Comment des travailleurs marocains ont-ils été utilisés pour fermer les mines de charbon du Nord-Pas-de-Calais ? C'est à cette question que répond cette thèse. Elle s'inscrit dans une histoire économique du secteur charbonnier, et dans une socio-histoire des politiques migratoires vues du point de vue non pas de l'Etat mais d'une entreprise, de ses dirigeants et des agents impliqués dans le recrutement, l'administration et le contrôle de ces travailleurs immigrés. Alors que les puits d'extraction du charbon ferment les uns après les autres dans le Nord-Pas-de-Calais, comprendre quel a été le rôle des travailleurs marocains nécessite de situer leurs trajectoires professionnelles dans une histoire de la lente disparition du groupe professionnel des mineurs. Le contexte colonial pèse aussi lourdement, interrogeant les relations entre institutions étatiques et entreprises de part et d'autre de la Méditerranée, ainsi que les modalités d'importation de schèmes racialistes et de pratiques d'encadrement et de contrôle des populations.Cette recherche s'inscrit ainsi à l'intersection d'une sociologie économique de l'entreprise et de la régulation par l'Etat d'un secteur économique, et d'une sociologie historique du travail des politiques migratoires, et de la classe ouvrière. Afin de comprendre la manière dont une grande entreprise a mené, dans la durée, une politique de recrutement de travailleurs immigrés, il est nécessaire de mener l'analyse conjointe des transformations du système productif et des conditions économiques de production de l'entreprise, de l'évolution de la politique de main-d’œuvre interne à l'entreprise, et des trajectoires individuelles au sein d'un groupe professionnel segmenté et hiérarchisé.Les sources mobilisées sont constituées des fonds d'archives des Houillères du Nord-Pas-de-Calais et des Charbonnages de France, des fonds relatifs à la politique charbonnière des gouvernements français, des écrits et débats au sein d'un petit groupe d'ingénieurs-économistes du corps des Mines ayant contribué au pilotage de la récession charbonnière, et de dossiers de carrière de travailleurs des mines. Deux types de quantification sont mis en œuvre : à partir de statistiques de gestion et de main-d’œuvre produites par l'entreprise, et à partir d'un échantillon de 400 dossiers de carrière de mineurs (200 Marocains et 200 non marocains).De la nationalisation du secteur minier à la fermeture du dernier puits du Nord-Pas-de-Calais en 1990, apparaissent les liens entre politiques économiques, évolution du capitalisme français et modalités concrète de la construction, de l'affaiblissement, et de la disparition d'une frange importante de la classe ouvrière. / How were Moroccan workers utilised to close coal mines in the Nord-Pas-de-Calais ? This thesis answers this question by studying the economic history of coal mining in France, and migration policies. Such a historical sociology of migrations sees migration policies from the point of view of a firm -- and not of a state --, and of the agents who contributed to the recruitment, management and control of these migrant workers. As coal pits were being closed one by one, understanding the role of Moroccan workers requires to analyse both their professional trajectories and the slow historical process of disappearing of coal miners. Colonial context also weights heavily, raising the issues of the relationships between state institutions and companies on each shore of the Mediterranean Sea, and of the modalities of importation of racialist ideals and of practices of population management and control.This research is defined at the crossing of an economic sociology of the firm and of state regulation of an economic sector, and a historical sociology of work, migration policies and the working class. In order to understand the way a big company implemented, on the long run, a recruitment policy of immigrant workers, one needs to analyse the transformations of productive systems, the evolutions of the firm's workforce policy, and the individual trajectories of a segmented and hierarchised professional group. Sources are constituted of archives of the Houillères de Nord-Pas-de-Calais and of Charbonnages de France, of archives of the governments coal policies, of writings and debates amongst a small group of engineers-economists (Corps des Mines) who contributed to the piloting of coal recession, and of carreer files of mine workers. Two types of quantification are implemented: from the firm's administrative and workforce policy, and from a sample of 400 career files (200 Moroccans, 200 non Moroccans). From the nationalisation of the whole mining sector to the closing of the last pit in the Nord-Pas-de-Calais, this history manifests the relationships between economic policies, the evolution of French capitalism, and the concrete modalities of the construction, weakening and disappearing of an important segment of the working class.

Les limitations récentes imposées par ICAO-CAEP, qui règlent les émissions de NOx, mènent à l’implémentation du concept de combustion lean dans les moteurs aéronautiques. Du point de vue du design, il faudrait étudier de façon plus approfondie la combustion lean et donc la Computational Fluid Dynamics(CFD) peut être un outil essentiel à ce but. Plusieurs phénomènes sont impliqués et différentes stratégies de modélisation, avec des différences en termes de coûts de calcul, sont disponibles. Néanmoins, jusqu'à présent, peu d'outils numériques peuvent prendre en compte les effets de la préparation du combustible liquide dans les calculs réactifs. Les conditions limites d’atomisation sont normalement déterminées par des approches corrélatives qui ne couvrent pas toutes les conditions de fonctionnement et les caractéristiques géométriques des brûleurs aéronautiques. Cependant, comme on peut lire dans la première partie de ma thèse, où plusieurs études de cas de littérature sont analysées, l'impact de la préparation du combustible liquide peut être extrêmement important. Les considérations basées sur des approches corrélatives ne sont pas fiables. Des méthodes prédictives focalisées sur l'atomisation du combustible sont nécessaires. Cette activité de recherche vise donc à développer un outil numérique général, utilisable dans le domaine industriel et capable de modéliser la phase liquide de son injection jusqu'à la génération d'un spray dispersé. Le modèle ELSA (Eulerian Lagrangian Spray Atomization), basé sur une approche eulérienne dans la région dense et une lagrangienne dans la zone diluée, a été choisi à ce but. Le solveur traite le combustible liquide jusqu'à la génération d'une phase dispersée et prend en compte le processus d’atomisation par l'introduction de la densité d'interface liquide-gaz. Néanmoins, si on applique cette méthode dans un environnement réactif fortement turbulent comme un brûleur aéronautique on peut rencontrer plusieurs limites. Par conséquent, on a dédié une attention particulière tout d’abord à l'étude du terme de flux turbulent à l'intérieur de l'équation de la fraction volumique liquide. Cette quantité est d'une importance primaire pour un écoulement turbulent, avec des vitesses de glissement élevées entre ses phases. Une nouvelle fermeture de second ordre pour cette variable est proposée et validée sur un cas de jet en crossflow. Ensuite, pour gérer un environnement réactif, un nouveau modèle d'évaporation est intégré dans le code et évalué par rapport aux résultats expérimentaux. Enfin, une autre méthode de dériver la distribution de la taille des gouttes dans le contexte ELSA pour l'injection lagrangienne est présentée et validée avec des simulations DNS. Pour conclure, ce travail introduit une nouvelle méthode pour une description unifiée de la combustion et de l’atomisation dans les calculs CFD. L'approche proposée devrait conduire à une description complète de l'évolution du combustible et à une caractérisation plus pertinente de l'écoulement réactif. Plusieurs aspects qui sont également mis en évidence sont améliorables et peuvent offrir des suggestions pour d’ultérieurs travaux. / The recent limitations imposed by ICAO-CAEP, regulating NOx emissions, are leading to the implementation of lean burn concept in the aero-engine framework. From a design perspective, a depth insight on lean burn combustion is required and Computational Fluid Dynamics (CFD) can be a useful tool for this purpose. Several interacting phenomena are involved and various modelling strategies, with huge differences in terms of computational costs, are available. Nevertheless, up to now few numerical tools are able to account for the effects of liquid fuel preparation inside reactive computations. Spray boundary conditions are normally determined thanks to correlative approaches that are not able to cover the wide range of operating conditions and geometrical characteristics of aero-engine burners. However, as highlighted in the first part of the dissertation, where several literature test cases are analysed through numerical calculations, the impact of liquid preparation can be extremely important. Considerations based on correlative approaches may be therefore unreliable. More trustworthy predictive methods focused on fuel atomization are required. This research activity is therefore aimed at developing a general numerical tool, to be used in an industrial design process, capable of modelling the liquid phase from its injection till the generation of a dispersed spray subject to evaporation. The ELSA (Eulerian Lagrangian Spray Atomization) model, which is based on an Eulerian approach in the dense region and a Lagrangian one in the dilute zone, has been chosen to this end. The solver is able to deal with pure liquid up to the generation of a dispersed phase and to account for the breakup process through the introduction of the liquid-gas interface density. However, several limitations of such method arise considering its application in a highly swirled reactive environment like an aero-engine burner. Therefore, particular attention has been here devoted first to the study of the turbulent liquid flux term, inside the liquid volume fraction equation. This quantity is of paramount importance for a swirled flow-field, with high slip velocities between phases. A completely innovative modelling framework together with a new second order closure for this variable is proposed and validated on a literature jet in crossflow test case. Then, to handle a reactive environment, a novel evaporation model is integrated in the code and assessed against experimental results. Finally, an alternative way to derive the Drop Size Distribution (DSD) in ELSA context for the lagrangian injection is presented and assessed by means of Direct Numerical Simulations. Ultimately, this work introduces an innovative framework towards a uni- fied description of spray combustion in CFD investigations. The proposed approach should lead to a comprehensive description of fuel evolution in the injector region and to a proper characterization of the subsequent reacting flow-field. Several improvable aspects are also highlighted, pointing the way for further enhancements.

Tesis para optar al grado de Magíster en Gestión y Administración de Empresas / Christhal Zúñiga [Parte I Análisis estratégico y de mercado], Juan Amigo [Parte II Análisis organizativo - financiero] / Autores no envían autorización para el acceso a texto completo de su documento / Debido a la topografía de Chile existen numerosas actividades industriales y productivas que se desarrollan en zonas de difícil acceso en las cuales los drones pueden ser de gran ayuda. Para apoyar a estas empresas en labores de seguridad, vigilancia y monitoreo, se creó una propuesta de valor que consiste en generar eficiencia operacional mediante la utilización de tecnología avanzada de seguridad y monitoreo a través de drones, así como la prevención de incidentes para lograr eficiencia en los procesos de los clientes y el acceso a las imágenes captadas por los equipos vía web en tiempo real. Además se propone dar un aporte a la gestión realizando informes de incidentes y de monitoreo periódico. El mercado objetivo son las empresas de distribución y generación de energía, de telecomunicaciones, mineras, empresas que cuenten grandes estructuras (puentes, edificios, torres de alta tensión, generadores eólicos de gran tamaño, etc.) y empresas de seguridad que prestan servicios a las antes mencionadas. Existen dos factores claves para el éxito de la compañía, el primero consiste en la disponibilidad del servicio, 24 horas durante 365 días del año, y la oportunidad, que consiste en garantizar tiempos de respuesta acordes a las necesidades de los clientes. Las operaciones están enfocadas en asegurar el cumplimiento de estas dos premisas mediante una estructura funcional liviana, flexible y dinámica. Además, el diseño de los sistemas y procesos se hará bajo la lógica de redundancia (N+1), esto es, cada recurso crítico utilizado en los procesos críticos (N) contará con un recurso adicional como backup (+1). En términos prácticos, si se necesita de 1 equipo dron para cubrir un radio de 100 km, se dispondrá de otro equipo de similares características para cubrir la misma zona en caso de falla del primero. Según el análisis financiero realizado, el negocio es intensivo en uso de capital y encuentra el punto de equilibrio alrededor del tercer año cuando logra tener una cobertura a nivel nacional lo que favorece la rentabilidad de este negocio lucrativo en el mediano y largo plazo. Una vez que se haya cubierto la brecha de aprendizaje, esta solución puede ser escalable a otras industrias así como a nivel sudamericano debido a que existen otros países con configuración geográfica similar a la Chilena.

Le but de cette thèse est de développer la théorie de Freidlin-Wentzell pour des modèles des épidémies, afin de prédire le temps mis par les perturbations aléatoires pour éteindre une situation endémique "stable". Tout d'abord nous proposons une nouvelle démonstration plus courte par rapport à celle établit récemment (sous une hypothèse un peu différente, mais satisfaite dans tous les exemples de modèles de maladie infectieuses que nous avons à l'esprit) par Kratz et Pardoux (2017) sur le principe de grandes déviations pour les modèles des épidémies. Ensuite nous établissons un principe de grandes déviations pour des EDS poissoniennes réfléchies au bord d'un ouvert suffisamment régulier. Nous établissons aussi un résultat concernant la zone du bord la plus probable par laquelle le processus solution de l'EDS de Poisson va sortir du domaine d'attraction d'un équilibre stable de sa loi des grands nombres limite. Nous terminons cette thèse par la présentation des méthodes "non standard aux différences finis", appropriés pour approcher numériquement les solutions de nos EDOs ainsi que par la résolution d'un problème de contrôle optimal qui permet d'avoir une bonne approximation du temps d'extinction d'un processus d'infection. / In this thesis, we develop the Freidlin-Wentzell theory for the "natural'' Poissonian random perturbations of the above ODE in Epidemic Dynamics (and similarly for models in Ecology or Population Dynamics), in order to predict the time taken by random perturbations to extinguish a "stable" endemic situation. We start by a shorter proof of a recent result of Kratz and Pardoux (under a somewhat different hypothesis which is satisfied in all the cases we have examined so far), which establishes the large deviations principle for epidemic models. Next, we establish the large deviations principle for reflected Poisonian SDE at the boundary of a sufficiently regular open set. Then, we establish the result for the most likely boundary area by which the process will exit the domain of attraction of a stable equilibrium of an ODE. We conclude this thesis with the presentation of the "non - standard finite difference" methods, suitable to approach numerically the solutions of our ODEs as well as the resolution of an optimal control problem which allows to have a good approximation of the time of extinction of an endemic situation.

This research addresses how interregional interaction changed between the Viejo period (AD 700-1200) and Medio period (AD 1200-1450) in northwest Chihuahua, Mexico. Non-locally procured or created artifacts, features, and iconographic elements are used as proxy evidence for past long-distance relationships. Data available in technical reports and other publications concerning these materials in Viejo period contexts and a sample of excavated Medio period sites are synthesized and presented. The data are used to create a geospatial dataset and distribution maps with quantities and contextual information for each of the nonlocal materials. I argue that interaction and social networks with long-distance neighbors were complex and widespread during both the Viejo and Medio periods. These intricate relationships morphed and altered in profound ways with the rise of the regional center Paquimé and the fluorescence of the Casas Grandes cultural tradition, but some of the fundamental relationships also remained the same.

L’expansion et l’intensification agricole ont d’énormes conséquences sur la biodiversité. L’étude des compromis entre production et biodiversité peut aider au ciblage de mesures en faveur de la biodiversité.L’objectif de la thèse était de révéler des stratégies d’utilisation des sols agricoles qui permettraient d’enrayer le déclin des oiseaux agricoles tout en maintenant la production dans un territoire partagé entre grandes cultures et élevage de ruminants.Notre travail s’est basé sur l’étude de corrélations entre des variables décrivant l’utilisation des sols agricoles, la production agricole et plusieurs descripteurs des communautés d’oiseaux dans les milieux agricoles français.Nous avons observé des communautés d’oiseaux très spécialisées et pauvres en espèces dans les régions à haute production végétale ; et des communautés dominées par des oiseaux généralistes dans les régions à haute production animale. La stratégie qui maximise le FBI (un indice d’abondance des oiseaux agricoles) en maintenant la production dans ses composantes animale et végétale combinait une légère extensification des grandes cultures, le renforcement des régions d’élevage extensif et l’intensification des régions d’élevage déjà intensives.Nos résultats soulignent la nécessité d’adopter des solutions différenciées à la production animale et à la production végétale, au-delà de la dichotomie land sparing/land sharing. / Agricultural expansion and intensification have disastrous consequences on biodiversity. Studying the relationship between biodiversity and food production can help devise appropriate measures.The objective of this work was to reveal land use strategies to halt the decline of farmland birds while maintaining agricultural production.Our work was based on the study of correlations between agricultural land use, food production, and various bird community descriptors across French agroecosystems.In high crop production regions, we observed low-diversity communities dominated by few arable specialist species. In high livestock production regions, we observed communities dominated by generalist bird species. The land-use strategy that maximized the Farmland Bird Index under crop and livestock production constraints involved a decrease of crop intensity in the most intensive crop regions and an increase of livestock intensity in the most intensive livestock regions. Extensive livestock production was reinforced in current extensive areas.Our results have shown that different strategies are needed in crop-dominated and in livestock dominated regions.