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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.
331

Electron and laser interactions with positive ions

McKenna, Paul January 2000 (has links)
No description available.
332

Réflexions et contributions méthodologiques à l'ACV de bâtiments neufs : modélisation du contributeur énergie / Considerations and methodological contributions to LCA of new buildings : energy module

Fouquet, Marine 11 December 2015 (has links)
Depuis 1974, date de l'apparition des exigences thermiques sur les bâtiments en France, les réglementations thermiques n’ont cessé d'évoluer pour rendre les bâtiments de plus en plus performants énergétiquement. Aujourd'hui, il apparaît nécessaire d'introduire d'autres indicateurs que la seule consommation d'énergie comme critère de performance d'un bâtiment.L'évaluation environnementale des bâtiments se base sur l'analyse de cycle de vie (ACV). A l'heure actuelle, il existe différents logiciels dédiés à l'ACV bâtiment avec leurs données, leurs méthodologies et leurs indicateurs propres.Par ailleurs, le développement des bâtiments producteurs d'énergie et des systèmes de gestion de la demande électrique soulève de nouvelles problématiques. En effet, l'approche actuelle en ACV tend à utiliser des résultats de simulations thermiques agrégés à l'année alors que pour évaluer les avantages et inconvénients de tels systèmes une granulométrie temporelle plus fine est plus adaptée.Les travaux de cette thèse portent plus particulièrement sur le calcul des impacts environnementaux de la consommation d'énergie en phase d'utilisation et visent à répondre aux problématiques suivantes :Comment, à partir d'un bilan énergétique exhaustif, peut-on récupérer l'information nécessaire à l'évaluation de l'énergie utilisée tout au long du cycle de vie d'un bâtiment ?Par la suite, quelles données environnementales pertinentes peut-on lui affecter ?Comment exprimer et afficher les résultats des impacts liés à cette utilisation d'énergie ?Ainsi, pour les bâtiments producteurs d'énergie, l'échelle de temps à laquelle doit être effectué le bilan énergétique (calcul import/export/autoconsommation) pour évaluer de manière correcte les impacts environnementaux liés à l'usage d'énergie est identifiée. De plus, un bâtiment peut utiliser des énergies renouvelables en profitant de la synergie que peut créer un ensemble de bâtiments, (mutualisation des productions en utilisant les meilleurs emplacements, foisonnement des consommations qui permet une éventuelle meilleure autoconsommation de la production). La manière dont le bilan import/export doit être effectué dans ce cas est déterminée.Les variabilités temporelles et spatiales des mix énergétiques utilisés dans le bâtiment à court et moyen terme sont caractérisées pour mettre en évidence leur influence sur les impacts environnementaux. Puis, l'utilisation de facteurs de caractérisation dynamique sur des cas d'études permet de mieux cerner les potentialités de l'ACV dynamique dans le bâtiment.Enfin, les différences dues aux méthodologies de prise en compte de l'énergie produite localement sur l'expression des résultats d’ACV sont présentées. Par ailleurs, la sensibilité des résultats d'ACV et des valeurs de référence à la variabilité de la donnée environnementale du mix électrique est exposée. / In France, since 1974 when the first thermal regulation on buildings appeared, thermal regulations have never stopped evolving in order to make more and more energy efficient buildings. Today, it is necessary to add new indicators, and not only energy, to describe building performance.Life Cycle Assessment (LCA) is the basis for buildings environmental assessment. Several building LCA software currently exist; they have their own methodologies and indicators.Besides, the development of buildings producing energy and of electrical load management systems raises new questions. Indeed, the current LCA practice use results from dynamic energy simulation at yearly level whereas assessing benefits and drawbacks of such systems has to be done with a smaller time step.This thesis is particularly focused on the calculation of the environmental impacts from energy consumption during the building use phase and aims to answer the following questions:From a complete energy balance, how can we extract information necessary to the assessment of energy consumption during the building life cycle?Then, which environmental data are relevant and should be assigned?How can you express and display impacts linked to energy use?Thus, for buildings producing energy, the time step that should be used for the energy balance (i.e. differentiation between energy consumed on site, exported and imported) in order to assess properly environmental impacts of energy consumption is identified. Moreover, a building can benefit from renewable energy sharing and thus, the way to realize the energy balance for building block is determined.Temporal (short and long term) and spatial variations of energy mixes used in a building are characterized in order to show their influence on the environmental impacts. Then, the use of dynamic characterisation factors on case studies allows to better understand the potentials of dynamic LCA for buildings.Last but not least, the differences between methodologies to handle onsite energy production on the results are presented. Besides, the sensibility of the LCA results and reference values to the variation of the electricity mix environmental data is displayed.
333

Le temps verbal en espagnol

Arias Bedoya, Claudia Beatriz 08 1900 (has links)
No description available.
334

Illegitimate identity in the middle of an ideological crisis and tensions in the consumption network: a study on why plus-size fashion brands are illegitimate fashion elements

Zanette, Maria Carolina 10 March 2016 (has links)
Submitted by Maria Carolina Zanette (carolzanette@gmail.com) on 2016-04-06T14:25:26Z No. of bitstreams: 1 Tese final final mesmo 2.pdf: 1433487 bytes, checksum: 11d14fb3b96c2ac8b8773788aafa0d9d (MD5) / Rejected by Pamela Beltran Tonsa (pamela.tonsa@fgv.br), reason: Boa tarde Maria Carolina. Para que possamos aprovar seu trabalho é necessário alguns ajustes conforme norma ABNT/APA. * Você inverteu a ordem, pois deve ser CAPA - CONTRA CAPA - FICHA CATALOGRÁFICA. * A ficha catalográfica é na 3ª pagina, pois quando impressa, fica no verso da contra capa. Após os ajustes você deve submete-lo novamente para analise e aprovação. Qualquer duvida estamos a disposição, Pãmela Tonsa 3799-7852 on 2016-04-06T16:23:52Z (GMT) / Submitted by Maria Carolina Zanette (carolzanette@gmail.com) on 2016-04-06T17:12:49Z No. of bitstreams: 1 Tese final final mesmo 3.pdf: 1821304 bytes, checksum: 6e8ee30f04b4059805d8385670f3dc80 (MD5) / Approved for entry into archive by Pamela Beltran Tonsa (pamela.tonsa@fgv.br) on 2016-04-06T18:38:23Z (GMT) No. of bitstreams: 1 Tese final final mesmo 3.pdf: 1821304 bytes, checksum: 6e8ee30f04b4059805d8385670f3dc80 (MD5) / Made available in DSpace on 2016-04-06T21:01:54Z (GMT). No. of bitstreams: 1 Tese final final mesmo 3.pdf: 1821304 bytes, checksum: 6e8ee30f04b4059805d8385670f3dc80 (MD5) Previous issue date: 2016-03-10 / This Dissertation explores why the plus size fashion field lacks legitimacy with plus size consumers. I have explored the subject in three papers. In the first paper, I study the process of legitimacy of a new emergent market, the Brazilian plus-size fashion market, and the challenges to institutionalization that it faces. I conducted seventeen interviews, performed netnography in four Brazilian plus-size fashion blogs and analyzed in a semiotic fashion an e-commerce shop that sells plus size fashion clothes. My results indicate that despite having legitimate actors promoting these plus size fashion brands, the plus size fashion field is still perceived as a shameful version of the fashion field. I argue here that the fact that one of the logics of the plus size fashion field being stigma, it affects derogatorily consumers’ identity projects in a way that prevents them from engaging in within the field cultural capital practices. In the second paper, I conducted a genealogical introspection in which I researched identity issues. As a (selfproclaimed) plus-sized woman I figured it would be relevant to look inside myself in order to explore how my identity entangles with the semiotic-material network that surrounds me in terms of both fashion, food and other elements. My data came both from concurrent and retrospective introspection techniques. In theoretical terms, I used the idea of assemblages and I focused my analysis both on the material aspects of my network of consumption and on the stability of this network. The consequences of my assemblage are linked to a total quality management of my identity, both online and offline, reflected on consumption practices that connect to the idea of a bulimic consumption logic on which food consumption and body management are interlinked. On my third paper, I examine the concept of identity from the perspective of plus size women´s consumption of fashion. Fourteen phenomenological interviews were conducted and analyzed from a hermeneutical perspective. Three thematic categories emerged from the data analysis: the construction of identity through fashion, elements of plus size identity and creative strategies to deal with the lack of products for plus size women in retail. Among the main results, the way the term plus size acts as stigma, influencing consumer´s identity projects, the role of retail in the stigmatization process and the shopping epic saga, which involves a ‘black market’ with the participation of sellers. Finally, I conclude discussing the role of identity in the instability of the plus size fashion field. / O presente trabalho explora as causas pelas quais o campo da moda plus size carece de legitimidade com as consumidoras plus size. Eu explorei o assunto em três artigos. No primeiro, eu estudo o processo de legitimação de um novo mercado emergente, o mercado da moda plus size brasileira e os desafios para sua a institucionalização. Eu conduzi dezessete entrevistas com consumidoras plus size, uma netnografia em quatro blogs de moda plus size brasileiros e analisei de maneira semiótica um site que vende roupas de moda plus size. Meus resultados indicam que, apesar de ter atores legítimos que promovem essas marcas de moda plus size, o campo da moda plus size ainda é percebido como uma versão vergonhosa do campo da moda. Defendo aqui que o fato de uma das lógicas de campo da moda plus size ser estigma, acaba afetando os projetos identitários das consumidoras de maneira depreciativa, de forma elas não se envolvem em práticas de capital cultural que ocorrem dentro do campo da moda plus size. No segundo artigo, eu conduzi uma introspecção genealógica em que eu pesquisei questões de identidade. Como uma mulher (que se assume ) plus size, eu imaginei que seria relevante para olhar para dentro de mim mesma, a fim de explorar a forma como a minha identidade liga-se com a rede semiótica-material que me rodeia em termos de moda, alimentos e outros elementos. Meus dados vieram tanto de técnicas de introspecção simultâneas, quanto retrospectivas. Em termos teóricos, eu usei a ideia de ―assemblages‖ e eu foquei minha análise tanto nos aspectos materiais da minha rede de consumo, quanto na estabilidade da rede. As consequências da minha assemblage estão ligadas a uma gestão de qualidade total da minha identidade, tanto online como off-line, refletidas em práticas de consumo que se conectam à ideia de uma lógica de consumo bulímica em que o consumo de alimentos e gestão corpo estão interligadas. Por fim, no meu terceiro artigo, eu explorei o conceito de identidade a partir do consumo da moda feminina plus size. Foram feitas catorze entrevistas fenomenológicas, cujos dados foram analisados a partir de uma perspectiva hermenêutica. Três categorias temáticas emergiram da análise de dados: a construção da identidade por meio da moda, elementos de identidade plus size e estratégias criativas para lidar com a falta de produtos para mulheres plus size no varejo. Entre os principais resultados, destacam-se a forma como o termo plus size atua como estigma, influenciando projetos de identidade das consumidoras, o papel do varejo no processo de estigmatização e a saga épica de compras, que envolve um 'mercado negro', com a participação de vendedores. Eu concluo discutindo o papel da identidade na instabilidade do campo da moda plus size.
335

Les technologies de production tropicales et leurs champs d'applications en économie / Tropical production technologies and its applications in Economics

Andriamasy, Rabaozafy Louisa 21 September 2018 (has links)
Les mathématiques tropicales sont une branche des mathématiques correspondant à l'étude d'une algèbre modifiée grâce à la redéfinition de l'addition et de la multiplication. Les mathématiques tropicales sont généralement définies grâce au minimum et à l'addition (algèbre min-plus) mais le terme est parfois utilisé pour désigner l'algèbre max-plus, définie grâce au maximum et à l'addition. Briec et Horvath ont introduit une notion de convexité très proche qui apparait comme un cas limite d’opérateurs utilisés en théorie de l’optimisation par Avriel (1972) et de Ben-Tal (1977). En suivant cette ligne d’investigation, nous allons proposer, dans le domaine de l’économie de la production et de l’optimisation de portefeuille, une certaine classe de modèles économiques à élaborés à partir de ces notions. Pour ce faire, nous introduisons une nouvelle classe de technologie de production permettant de prendre en compte les structures d’homothe´tie-translation dans la mesure de productivité au travers du concept de la Convexité Max-Plus. Ensuite, nous allons établir une relation topologique entre plusieurs classes de modèles convexes généralisés connus. Nous analysons pour cela la limite de Painlevé-Kuratowski des modèles CES-CET et des technologies non paramétriques satisfaisant une hypothèse de rendements d’échelle alpha. On montre que leurs limites topologiques convergent vers les modèles de production B-convexe et Cobb-Douglas. Enfin, nous allons montrer que l'amélioration de l'efficacité technique d’une coalition d’entreprises s'avère compatible avec les technologies de semi-treillis dans un jeu coopératif. Nous introduisons ensuite, le concept d’écart absolu moyen dans la sélection du portefeuille en utilisant le « Shortage Function » qui prend en compte simultanément la réduction des inputs et l’augmentation des outputs comme dans la théorie de la production. Enfin, nous allons étendre le concept de B-convexité et de l’inverse B-convexité en se concentrant sur le calcul des mesures d’efficacité technique dans le graphe. / Tropical algebra is the tropical analogue of linear algebra by redefining the usual operation addition by the maximization operation and the usual addition operation as multiplication. Briec and Horvath introduced a concept of convexity very close to this concept quoted above which appears as one of the limits of use of the theory of optimization by Avriel (1972) and Ben-Tal (1977). Following this line of investigation, we give an overview of contributions involving a semilattice structure of production technologies and an optimization portfolio. To do that, firstly, we propose a framework allowing to consider both semilattice structure and translation homothetic properties in productivity measurement. We introduce the concept of Max-Plus convexity which combine both an upper semilattice structure and an additivity assumption. We establish a topological relation between several classes of known generalized convex models using some basic algebraic convex structures. We analyze the Painlevé-Kuratowski limit of the CES-CET and Alpha-returns to scale models. It is shown that their topological limits yield the B-convex and Cobb-Douglas production models. Moreover, we show that the improvement of technical efficiency is compatible with semilattice technologies in a cooperative game. Then, we introduce a criterion to measure portfolio efficiency based upon the minimization of the maximum absolute deviation and minimum absolute deviation from the expected return using the Shortage function. Finally, we derive simple closed-form expressions to calculate the hyperbolic measure in the case of inverse and B-Convexity that evaluates technical efficiency in the full input-output space.
336

Calcul d'itinéraires multiples et de trajets synchronisés dans des réseaux de transport multimodaux / Multiple itinerary and synchronized trip computation in multi-modal transportation networks

Scano, Gregoire 08 September 2016 (has links)
L’utilisation des réseaux de transport est conditionnée par l’efficacité et la simplicité de leur utilisation. En réponse à une mobilité exacerbée, volontaire ou subie, l’offre de transport se développe et motive tout à la fois, en un cycle continu, des déplacements encore plus exigeants. De manière complémentaire, la mobilité est bousculée par l’arrivée de nouvelles modalités de transport pouvant faire émerger, comme dans le cadre du covoiturage, des acteurs ou des pratiques jusqu’alors inexistants. Si la technologie permet de suivre cette évolution dans les services d’information aux voyageurs, il reste toujours à satisfaire des attentes déterminées par des usages en constante évolution. C’est de ce point de vue que l’obtention de chemins multiples pour relier une origine à une destination est un facteur qui n’est plus à négliger, surtout dans des réseaux de transport denses et comportant de nombreux modes et lignes de transport. Une liberté dans le choix laissé à l’utilisateur du réseau réduit les sentiments d’exclusion, d’incompréhension ou d’anxiété qui peuvent survenir face à une application logicielle ou sur internet et qui effectuent des choix arbitraires de façon autoritaire. De plus, cela permet de vérifier la qualité de l’offre de transport, car plus il existe de moyens différents pour effectuer un trajet dans un intervalle de temps donné, meilleur est le service. Cette thèse s’intéresse au calcul de telles alternatives par le biais de l’énumération par coût croissant des chemins entre deux points, puis par le filtrage de ceux-ci suivant des critères, supposés quelconques et laissés à l’appréciation des professionnels de transport qui peuvent ainsi faire varier les angles d’analyses de leurs offres.Par ailleurs, la synchronisation de trajets de plusieurs utilisateurs, en vue d’usages sociaux ou de déplacements mutualisés, est étudiée dans ce manuscrit sous l’angle du covoiturage. En ne considérant que deux usagers, l’objectif est de minimiser le temps de trajet global des participants sous la contrainte qu’ils partagent une partie de leur chemin entre un point de rencontre et un point de séparation qu’il faut alors déterminer. Sont également étudiées les variantes associées au changement des conditions de transport de chacun des participants comme l’établissement d’une origine ou d’une destination commune parallèlement à des contraintes sur les heures de départ ou d’arrivée des usagers. Enfin, puisque la voiture est très souvent pénalisée par la prise en charge d’un piéton, il convient d’étudier comment ce détour peut être contraint et les impacts sur les gains que cette limitation engendre.Cette thèse a été réalisée dans un contexte CIFRE pour la société MobiGIS. Lestravaux qui s’y rapportent ont fait l’objet de réalisations pratiques tant pour fournirdes solutions de mobilité dans le cadre des activités de l’entreprise que pour évaluerexpérimentalement les performances des algorithmes proposés pour les résoudre. / Efficiency and simplicity are two conditions upon which the use of a transportation system is relevant. May it be intentional or imposed, an increasing mobility triggers the need to enhance the transportation offer. In turn, such a response encourages an even more demanding mobility in a constantly adapting cycle. In parallel, new and forthcoming means of transportation emerge from time to time with unknown practices and renewed actors : exactly like what carpooling is stirring at the moment. Passenger information systems can technically deal with such evolutions thanks to improved technologies but they still struggle to keep up with constantly changing usage expectations.From this perspective the computation of several paths from an origin to a destination becomes increasingly relevant. This issue is even more crucial in dense transportation networks in which many modes and lines of transportation are combined. Indeed, giving some traveling choices to the end user reduces the feeling of exclusion, anxiety and the lack of understanding which may arise when facing arbitrary decisions dictated by a software or an Internet application. It is also helpful to estimate the quality of the transportation offer since the more paths exist to go from point A to point B within a fixed time window, the better the service is. This thesis focuses on the computation of such alternatives by the gradually increasing enumeration of paths between two points. Given this input, the pruning necessary to obtain such a diverse selection is assumed not to be known in advance. It is left up to transportation professionals who may choose a fitted solution based on their specific knowledge and objectives.Another subject studied in this thesis concerns the itinerary synchronization of several users for various social uses such as shared travels. It is here seen from the perspective of carpooling. Considering only two users, the problem is to minimize the traveling cost of the users under the constraint that they must share some part of their respective trips with one another. Solving this problem is equivalent to finding a pick up point and a drop off location between which both paths overlap. Multiple corner cases concerning the transportation conditions of each user as well as the special cases of shared origins or destinations are studied. The constraints on the arrival and/or departure times may also vary. Last but not least and since the driver is often penalized when giving up a lift, the restriction to a maximal detour the driver accepts, compared to his shortest path, is analyzed with respect to the benefits such a limitation generates.This thesis was funded by the MobiGIS company under the CIFRE (Industrial Agreement of Training through Research) researching context. The related work consisted in the practical implementation of mobility solutions within the framework of the company as well as the experimental performances evaluation of the algorithms proposed to solve them.
337

Conception préliminaire des actionneurs électromécaniques : approche hybride, directe/inverse / Preliminary design of electromechanical actuators : a hybrid, direct/inverse approach

Liscouet, Jonathan 04 January 2010 (has links)
L’objectif de cette thèse est de proposer des méthodes innovantes de conception préliminaire d’actionneurs électromécaniques (EMA) et de les implémenter sous la forme d’outils logiciels rapidement disponibles pour les industriels. Cet objectif répond à une demande forte de l’industrie, en particulier en aéronautique dans le cadre du développement d’avions plus électriques. Dans un premier temps, cette thèse propose une méthode hybride (montante et descendante) de recherche systématique d’architectures solutions et de sélection vis-à-vis des exigences du cahier des charges et de l’état de l’art technologique. Dans un deuxième temps, des méthodes d’évaluation d’architectures en termes de puissance, d’intégration (enveloppe géométrique et masse), de fiabilité et de performances en boucle fermée sont proposées. L’implémentation de ces méthodes se base sur la modélisation acausale et la combinaison de simulations numériques inverses et directes. Des lois d’échelle, représentatives des phénomènes physiques dimensionnants, sont établies pour réduire la complexité d’utilisation des modèles et l'intervention d’experts de domaine dans les phases préliminaires. Les méthodes proposées et leur implémentation dans l'environnement de simulation Modelica/Dymola ont été appliquées avec succès aux exemples d’actionneurs électromécaniques d’orientation d’un train avant d’atterrissage, de commandes de vol primaires et de contrôle de la poussée vectorielle du premier étage de propulsion d’un lanceur spatial. De cette façon, la durée de la phase d’évaluation d’architectures a pu passer d’un ordre de grandeur en jour à un ordre de grandeur en heure / The aim of this thesis is to propose innovative methods for the preliminary design of electromechanical actuators (EMA), and to implement them in software tools rapidly available for the industry. This objective is motivated by a strong demand of the industry, especially in aeronautics within the frame of the development of more electric aircrafts. First, this thesis puts forward a hybrid methodology (top-down/bottom-up) to generate and select systematically architectures with respect to requirements and the state of the art of technology. Second, methods to evaluate architectures in terms of power, integration (geometrical envelop and mass), reliability and closed loop performances are developed. The implementation of these methods is based on non-causal modelling combined to direct and inverse numerical simulations. Scaling laws, representative of the main sizing phenomena, are established to reduce the complexity of the models and the need for domain experts during the preliminary phases. The proposed methods and their implementation within the simulation framework Modelica/Dymola have been applied successfully to the examples of electromechanical actuators for the steering of a nose landing gear, the primary flight control of an aircraft and the thrust vector control of a space launcher. As a result, the duration of the architecture evaluation has been reduced from day-scale to hour-scale
338

Análise de SNIR e BER para redes acústicas submarinas

Ortega Blanco, Rubén 11 August 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2015. / Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2016-02-16T14:01:50Z No. of bitstreams: 1 2015_RubenOrtegaBlanco.pdf: 78834010 bytes, checksum: 3420abfa3f7efe2d616b97f09d14ff70 (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-02-19T21:04:29Z (GMT) No. of bitstreams: 1 2015_RubenOrtegaBlanco.pdf: 78834010 bytes, checksum: 3420abfa3f7efe2d616b97f09d14ff70 (MD5) / Made available in DSpace on 2016-02-19T21:04:29Z (GMT). No. of bitstreams: 1 2015_RubenOrtegaBlanco.pdf: 78834010 bytes, checksum: 3420abfa3f7efe2d616b97f09d14ff70 (MD5) / O objetivo do seguinte trabalho é determinar um modelo matemático que permita-nos obter a Relação Sinal Ruído mais Interferência (SNIR do Inglês Signal-to-Noise plus Interference Ratio), a Taxa de Erro de Bits (BER do Inglês Bit Error Rate) de um salto e a Taxa de Erro de Bits fim-a-fim numa rede acústica submarina. Com esse propósito foi desenvolvido um modelo matemático que permite o cálculo destes parâmetros considerando a interferência para o protocolo de acesso ao meio (MAC do Inglês Medium Access Control) ALOHA puro. Também foi necessário desenvolver antes diferentes parâmetros da rede, tais como, distância média do salto, distância média até o nó central, distância média entre os nós, número médio de saltos na rota e desvio médio. Com o uso deste modelo também é possível obter o valor da frequência ótima utilizando uma função de otimização. Comparações entre a Taxa de Erro de Bits de um salto e fim-a fim também forem feitas, para diferentes valores de máximo ângulo de desvio na topologia de rede usada. Estas comparações demonstran quando pode ser mais convenente o uso de um salto ou múltiple-salto. Simulações Monte-Carlo e modelo forem comparados com o propósito de validar os resultados obtidos. Estas comparações demostram a grande similitude entre nosso modelo e as simulações de Monte-Carlo. Além disso foi possível o estudo do comportamento da SNIR e do BER variando importante parâmetros da rede tais como frequência de transmissão, número de nós, raio da esfera e máximo ângulo de desvio. Os resultados obtidos provarem que a SNIR para um salto diminui com o aumento do número de nós e o raio da esfera, mas aumenta com o incremento da potência de transmissão. O comportamento de BER é contrário ao comportamento de SNIR. Também foi possível observar a existência da frequência ótima, onde os melhores valores de SNIR e o BER são obtidos. ______________________________________________________________________________________________ ABSTRACT / The objective of this work is to nd a mathematical model that allow us to obtain the Signal-to-Noise plus Interference Ratio (SNIR), the One-Hop Bit Error Rate (BER) and the End-to-End Bit Error Rate for an Underwater Acoustic Network (UAN). Considering this, it was developed a model that includes the interference as an important impairment and for ALOHA MAC (Medium Access Control) protocol. In addition, it was necessary to obtain before several parameters from the network, such as, average distance of the hop, average distance between nodes, average distance to the central node, average number of hops and average deviation. With this model, it is also possible to nd the optimal value of frequency using an optimization function. It was made comparisons between the One-Hop BER and the End-to-End BER for various values of maximal deviation angle. This comparison shows when it is more adequate to either use one-hop or multi-hop. Finally, we compared numerical and Monte-Carlo simulation results, giving a rst validation to our model. These comparisons show a big similitude between the developed model and the Monte-Carlo simulation. In addition, it was possible to analyse the behaviour of the SNIR and BER by varying important parameters of the network, such as, transmission frequency, number of nodes and sphere radius among others. From the obtained results it was prove that the SNIR decreases with an increase from the number of nodes and the sphere radius, but increases with the transmission power. The End-to-End BER has an contrary behavior with the SNIR.
339

Momento de aplicação de calcário e gesso em um latossolo vermelho distrófico, no desenvolvimento inicial do milho

Manetti, Fábio Augusto [UNESP] 05 September 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-09-05Bitstream added on 2014-06-13T18:52:22Z : No. of bitstreams: 1 manetti_fa_me_botfca.pdf: 473618 bytes, checksum: e05c02e7c8f686cc2f1ffa75ea5e1616 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / Com a finalidade de avaliar os efeitos do momento da aplicação isolados e conjuntos do calcário e do gesso no crescimento vegetativo de plantas de milho. O experimento foi instalado em casa de vegetação e conduzido na área experimental do Departamento de Recursos Naturais - Ciência do Solo, localizado na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - FCA da Universidade Estadual Paulista - UNESP, Campus de Botucatu, em um Latossolo Vermelho Distrófico, textura média, Unidade Patrulha. Os tratamentos foram:- T1- sem calcário calcítico e sem gesso (testemunha); T2 - com calcário calcítico e sem gesso; T3 - sem calcário calcítico e com gesso; T4 - calcário calcítico aplicado 30 dias antes da aplicação do gesso; T5 - calcário calcítico aplicado 15 dias antes da aplicação do gesso; T6 - calcário calcítico aplicado junto ao momento de aplicação do gesso (mistura); T7 - calcário calcítico aplicado 15 dias após a aplicação do gesso; T8 - calcário calcítico aplicado 30 dias após a aplicação do gesso; T9 - calcário calcítico e gesso (mistura) aplicado na superfície 30 dias antes da semeadura (das); T1- sem calcário dolomítico e sem gesso (testemunha); T2 - com calcário dolomítico e sem gesso; T3 - sem calcário dolomítico e com gesso; T4 - calcário dolomítico aplicado 30 dias antes da aplicação do gesso; T5 - calcário dolomítico aplicado 15 dias antes da aplicação do gesso; T6 - calcário dolomítico aplicado junto ao momento de aplicação do gesso (mistura); T7 - calcário dolomítico aplicado 15 dias após a aplicação do gesso; T8 - calcário dolomítico aplicado 30 dias após a aplicação do gesso; T9 - calcário dolomítico e gesso (mistura) aplicado na superfície 30 dias antes da semeadura (das). Esses tratamentos foram aplicados nos três primeiros anéis de 7,0 cm cada, totalizando 21 cm, de colunas de PVC de... / With the purpose to appraise the effects of the superposition, isolated and together, of the limestone and the gypsum in the vegetative growth of maize plants, to the forty days after the emergence, as well as in the extraction of the nutrients by the aerial portion of the plants, beyond its effects on the behavior of some chemical features from the superficial layer of the soil, was accomplished this study. The experiment had been settled and guided at the experimental area on Natural Resources Department - Soil Science, located in the Experimental Farm Lageado, of the Faculdade de Ciências Agronômicas - FCA - from Universidade Estadual Paulista - UNESP, Campus of Botucatu, in a dystrophic clayey Rhodic Hapludox, average texture, Unidade Patrulha.The treatments had been defined by the moments of the applications of the two types of limestones, calcitic and dolimitic, with and without gypsum and agricultural gypsum only. These treatments had been applied in three first rings of 7,0cm each, totalizing 21cm, from PVC columns of 49cm of height and 10cm of diameter. The experimental outlining had been made in blocks, in factorial arrangement of 9x2, with four repetitions.The harvest had been made to the forty days after the emergence, having been the plants cut close to the soil and measured like: heights from the stalk's base to the first sheath and the edge of the biggest leaf; stalk's diameter; numbers of leafs for plants; fresh and dry matter...(Complete abstract click electronic access below)
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O consumo crônico de aguardente de cana-de-açúcar induz efeitos ansiolíticos em camundongos

Sena, Maria Clécia Penha 14 February 2012 (has links)
Made available in DSpace on 2015-05-14T12:59:52Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1129921 bytes, checksum: 37f8fc894c14f9259858a469ffccab56 (MD5) Previous issue date: 2012-02-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Distilled sugarcane spirit is a genuine Brazilian beverage produced by distillation after fermentation of sugarcane and is appreciated not only in Brazil but worldwide. Although sugarcane spirit consumption is an important drive to increase alcoholism in Brazil, little is known about its chronic consumption on anxiety/anxiolytic effects. In the present study, we investigated whether the chronic consumption of sugarcane spirit is responsible for inducing anxiolytic-like effects. Male 3-3.5 month-old Swiss mice were exposed to the two-bottle free-choice paradigm for six weeks. Mice in group A were treated with sugarcane spirit + distilled water (n=16); in group B with ethanol + distilled water (n=15); and in group C (control) with distilled water + distilled water (n=14). The content of ethanol in beverages offered to groups A and B was 2% in the first week, 5% in the second week and 10% in the 4 remaining weeks. At the end of the treatments, animals were submitted to the elevated plus maze and the hole board test for assessment of anxiety-related behaviors. Serum aspartate aminotransferase (AST) and alanine amino transferase (ALT) levels were determined. The concentrations of ethanol, volatile acidity, esters, aldehydes, furfural, higher alcohols (n-propylic, isobutylic and isoamylics), methanol, copper and lead of the sugar cane were also determined. Time spent in open arms was increased in mice exposed to chronic ethanol (32±8 vs 7±2 s, p<0.05) or sugarcane spirit (36±9 vs 7±2 s, p<0.05), when compared to the control group. Conversely, the time spent in the closed arms was significantly decreased in animals drinking ethanol (183±6 vs 214±4 s, p<0.05) or sugarcane spirit (150±8 vs 214±4 s, p<0.05), when compared to the control group. In addition, the ratio of the time spent in the open arms over the total time spent in both closed and open arms was significantly increased (ethanol 34±8 vs 6±2 s; sugarcane spirit 43±12 vs 6±2 s, p<0.05. In the hole board test, mice treated with ethanol or sugarcane spirit showed an increase in the number of head-dipping behaviors, when compared to the control condition (control group: 16±1; ethanol: 27±2; sugarcane spirit: 31±3, p<0.05). In addition, motor activity in the hole board test was also increased in both ethanol and sugarcane spirit groups, when compared to the control condition (control group: 21±2; ethanol: 34±2; sugarcane spirit: 40±4, p<0.05). The chemical composition analysis showed that the concentrations of ethanol, volatile acidity, esters, aldehydes, furfural, higher alcohols (n-propylic, isobutylic and isoamylics), methanol, copper and lead in the sugarcane spirit were below the upper limits allowed by the Ministry of Agriculture regulations for the production of spirits. In conclusion, here we report that chronic consumption of sugarcane spirit produces liver injury and anxiolytic-like effects in mice. The more pronounced liver injury caused by sugarcane spirit as suggested by the AST/ALT ratio might have been caused by other organic compounds present in the sugarcane spirit while the anxiolytic-like effect seems to be caused by both ethanol and other compounds present in sugarcane spirit. The mechanisms by which sugarcane spirit leads to more rapid liver injury than does ethanol should be examined in future investigations. / A aguardente de cana-de-açúcar, uma bebida genuinamente brasileira obtida por fermentação seguida de destilação do mosto de cana de açúcar (Saccharum officinarum, L.), é apreciada não só no Brasil, mas mundialmente. Embora o consumo da aguardente de cana-de-açúcar seja um fator importante para o aumento do alcoolismo no Brasil, pouco se sabe sobre o seu consumo crônico na ansiedade ou efeitos ansiolíticos. No presente estudo, investigou-se se o consumo crônico da aguardente de cana-de-açúcar é responsável por induzir efeitos ansiolíticos. Camundongos Suíços machos com 3-3,5 meses de idade foram expostos ao paradigma de livre escolha com duas garrafas por seis semanas. Camundongos do grupo A foram tratados com aguardente de cana-de-açúcar + água destilada (n = 16); do grupo B com etanol +água destilada (n=15); e do grupo C (controle) com água destilada + água destilada (n = 14). O conteúdo de etanol nas bebidas oferecidas aos grupos A e B foi de 2% na primeira semana, de 5% na segunda semana e 10% nas 4 semanas restantes. No final dos tratamentos, os animais foram submetidos aos testes do labirinto em cruz elevado e da placa perfurada para avaliação dos comportamentos relacionados com a ansiedade. Os níveis séricos de aspartato aminotransferase (AST) e alanina aminotransferase foram determinados. As concentrações de etanol, acidez volátil, ésteres, aldeídos, furfural, álcoois superiores (n-propílico, isobutílico e isoamílico), metanol, cobre e chumbo da agurdente de cana-de-açúcar também foram determinados. O tempo gasto nos braços abertos foi aumentado em camundongos expostos ao consumo crônico de etanol (32±8 vs 7±2 s, p<0.05) ou de aguardente de cana-de-açúcar (36±9 vs 7±2 s, p<0.05), quando comparado ao grupo controle. Por outro lado, o tempo gasto nos braços fechados diminuiu significativamente nos animais que consumiram etanol (183±6 vs 214±4 s, p<0.05) ou aguardente de cana-de-açúcar (150±8 vs 214±4 s, p<0.05), quando comparado ao grupo controle. Além disso, a razão entre o tempo gasto nos braços abertos sobre o tempo total gasto em ambos os braços abertos e fechados foi significativamente aumentado (etanol 34±8 vs 6±2 s; aguardente de cana-de-açúcar 43±12 vs 6±2 s, p <0,05). No teste de placa perfurada, os camundongos tratados com etanol ou aguardente de cana-de-açúcar mostraram um aumento no número de mergulhos, quando comparado ao grupo controle (grupo controle: 16±1; etanol: 27±2; aguardente de cana-de-açúcar: 31±3, p<0.05). Além disso, a atividade motora no teste da placa perfurada também foi aumentada em ambos os grupos etanol ou aguardente de cana-de-açúcar, quando comparado ao grupo controle (grupo controle: 21±2; etanol: 34±2; aguardente de cana-de-açúcar: 40±4, p<0.05). A análise da composição química mostrou que as concentrações de etanol, acidez volátil, ésteres, aldeídos, furfural, álcoois superiores (n-propílico, isobutílico e isoamílico), metanol, cobre e chumbo na aguardente de cana-de-açúcar estavam abaixo do limite superior permitido pelos regulamentos do Ministério da Agricultura para a produção de bebidas destiladas. Em conclusão, aqui relatamos que o consumo crônico de aguardente de cana-de-açúcar produz lesão hepática e efeitos ansiolíticos em camundongos. A lesão hepática mais acentuada causada pela aguardente de cana-de-açúcar, como sugerido pela relação AST/ALT pode ter sido causado por outros compostos orgânicos presentes nesta bebida, enquanto o efeito ansiolítico parece ser causado tanto pelo etanol como pelos outros compostos presentes na aguardente de cana-de-açúcar. Os mecanismos pelos quais a aguardente de cana-de-açúcar leva a lesão hepática mais rápida do que o etanol devem ser examinados em futuras investigações.

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