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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.
161

Effect Of Initial Support Of Excavation On Seismic Performance Of Cut And Cover Structures

Rezaei, Hamidreza 01 May 2011 (has links) (PDF)
ABSTRACT EFFECT OF INITIAL SUPPORT OF EXCAVATION ON SEISMIC PERFORMANCE OF CUT AND COVER STRUCTURES Rezaei, Hamidreza M.Sc., Department of Civil Engineering Supervisor: Asst. Prof. Dr. Alp Caner MAY 2011, 66 pages The effect of the initial support and its embedment depth, on the seismic performance of cut and cover tunnels is investigated. Cut and cover construction is one of the fastest and cheapest methods for constructing rectangular shallow tunnels. Construction of cut and cover structure in soil usually starts with installation of the initial support of excavation system, which may consists of rigid type of initial supports such as tangent piles or secant piles. These systems usually remain in place after completion of the final structure. However, to simplify the design, it is a common practice to ignore the contribution of initial support. In this study the effect of initial support of excavation on the seismic performance of cut and cover tunnels is investigated by means of a detailed dynamic finite element analysis. Three different tunnel geometries, three soil types and three acceleration histories were considered Results of the study show that depending on the soil stiffness (soft, medium, or stiff soil), the dynamic response of the tunnel deformations are affected significantly by the initial support of excavation. The effect of the initial support diminishes as the quality of the soil improves. Therefore, dynamic analyses are recommended for the final design of this type of structures especially in soft soils.
162

Ekstradicijos samprata, pagrindai ir sąlygos / The concept and legal conditions of extradition in the criminal law

Sluškonytė, Lina 17 December 2006 (has links)
SUMMARY Extradition is the official process by which one nation or state requests and obtains from another nation or state the surrender of a suspected or convicted criminal. As between nations, extradition is regulated by treaties. As between states or other political subdivisions on a domestic level, extradition is more accurately known as rendition. The master thesis is a research of the concept of extradition in historical perspective, trying to overlook deeper the basics of this legal norm. The research of the concept of extradition in historical perspective, trying to overlook deeper the basics of this legal norm. The research is made by comparing the institute of extradition and institute of fugitives in the context of international law, other legal acts. Fundamental legal acts of extradition are thoroughly discussed in the master thesis. The author presents the analysis of conventions, bilateral, agreements, national laws of extradition, principle of reciprocity and moral human rights. The author presents opinions of various contemporary Lithuanian scientists such as V. Vadapalas, A. Nevera, A. Čepas, J. Žilinskas, G. Goda, M. Kazlauskas, P. Kuconis, G. Švedas, L. Visockienė. Also were used fundamental works about extradition by M. Akehurst, S. Bedi, G. Gilbert, H. Lauterpacht, I. A. Shearer, A. Boicov, R. Valejev, J. Vasiljev, B. Velčev, L. Galenskaja etc. International agreements, national criminal laws and laws of criminal procedure are also analyzed in the study... [to full text]
163

Development of a precipitation index-based conceptual model to overcome sparse data barriers in runoff prediction in cold climate

Akanegbu, J. O. (Justice Orazulukwe) 07 December 2018 (has links)
Abstract This thesis describes the development of a new precipitation index-based conceptual water balance model with parameters easily regionalized through the functional relationship with catchment and climate attributes. It also presents a simple method for improving model dynamics for streamflow simulations in a non-stationary climate. The model was developed for streamflow modelling and prediction in high-latitude catchments, where model parameter regionalization is difficult due to limited availability of hydrological data for the region. The model couples a snow accumulation and melt formulation with a current precipitation index (CPI) formulation to simulate daily precipitation in runoff hydrograph pattern from catchments with seasonal snow cover. Using new runoff conversion factors CT and Lf, and a threshold flow factor ThQ, the simulated CPI hydrograph is converted into daily runoff and routed using the transformation function Maxbas. The model was developed in Microsoft Excel workbook and tested in 32 catchments in Finland, a region with considerable seasonal snow cover. The results showed that the model can adequately simulate and reproduce the dynamics of daily runoff from catchments where the underlying physical conditions are not known. In addition, incorporating temperature conditions influencing inter-annual variability in streamflow into the model structure improved its structural dynamics, thereby improving its performance in a non-stationary climate. Most model parameters showed strong relationships with observable catchment characteristics, climate characteristics, or both. The parameter functional relationships derived from the model parameter-catchment relationships produced equally good model results when applied to independent test catchments used as mock-ungauged catchments. Inclusion of snow-water equivalent records and use of multiple objective functions for snow-water equivalent and runoff simulations during model optimization helped reduce the effect of parameter equifinality, making it easier to determine optimal parameter values. The current precipitation index (CPIsnow) model is a parsimonious tool for predicting streamflow in data-limited high-latitude regions. / Tiivistelmä Tämä väitöskirja käsittelee yksinkertaisen sadantaan perustuvan konseptuaalisen vesitasemallin kehitystä ja soveltamista boreaalisille valuma-alueille sekä malliin liittyvää alueellista parametrisointia valuma-alueominaisuuksien ja ilmastoaineiston perusteella. Hydrologinen malli on luotu laskemaan ja ennustamaan valuntaa pohjoisille valuma-alueille, joilta on vähän hydrologista tietoa. Malli yhdistää lumen kertymisen ja sulannan tunnettuun sadantaindeksiin perustuvaan malliin (CPI) ja edelleen simuloi päivittäisen hydrografin valuma-alueille, joilla on selkeä lumipeitteinen ajanjakso. Malli laskee MaxBas funktion avulla CPI:llä muodostetun hydrografin päivittäiseksi valunnaksi valuntaan liittyvien malliparametrien CT ja Lf sekä virtaaman kynnysarvon ThQ avulla. Malli kehitettiin Excel-ympäristössä ja sitä testattiin 32 valuma-alueella Suomessa. Valuma-alueet edustivat maantieteellisesti kattavasti alueita, joilla esiintyy tyypillisesti kausittainen lumipeite. Saadut tulokset osoittivat, että kehitetty malli simuloi ja tuottaa päivittäisen valunnan riittävällä tarkkuudella valuma-alueille, vaikka hydrologista ja fysikaalista tietoa alueilta olisi niukasti. Useimmat malliparametrit olivat vahvasti riippuvaisia joko valuma-alue ominaisuuksista tai ilmastollisista parametreista tai molemmista. Parametrien funktionaalinen yhteys muodostettiin valuma-alueiden ominaisuuksien perusteella ja testattiin riippumattomalla valuma-aluejoukolla hyvin tuloksin. Malliparametrien samatavoitteellisuutta eli ekvifinaliteettiä voitiin vähentää huomioimalla mallissa lumen vesiarvomittaukset sekä hyödyntämällä useita parametrisia funktioita. Tällöin myös optimaalisten parametrien löytyminen nopeutui ja helpottui. Tämän väitöstyön pohjalta syntynyt uusi sadannan indeksiin pohjautuva laskentamalli (CPIsnow) mahdollistaa valunnan arvioinnin pieniltä valuma-alueilta, joilta on niukasti aineistoa saatavilla ja joissa lumen sulanta ja kertyminen ovat keskeisiä hydrologisia prosesseja.
164

The victims within the reformed criminal justice system / Las víctimas en el sistema procesal penal reformado

Pásara Pazos, Luis 10 April 2018 (has links)
This article analyzes the negative impact of the reforms within the criminal systems in Latin America, both for those who suffer a crime, and those who are accused of having committed such crime. Supprted by empirical data, the author warns how the innovations of the reformed criminal proceedings (for example, the simplified court proceeding or the active role played by prosecutors), by enrolling into an authoritative legalculture, become in practice contrary to their likely design. / El presente artículo analiza la incidencia negativa de las reformas llevadas a cabo en los sistemas penales de América Latina, tanto en relación a quien sufre un delito, como respecto a quien es acusado de haberlo cometido. Sustentado en información empírica, el autor advierte cómo las novedades del proceso penal reformado (por ejemplo, el procedimiento abreviado o el rol activo a desempeñar por los fiscales), al inscribirse en una cultura jurídica autoritaria, devienen en la práctica en formas contrarias a su diseño ideal.
165

L'intégration des données énergétiques dans la conception architecturale située / Morpho-energetic investigations to assess buildings and city areas energy performance

Arantes, Laëtitia 23 January 2013 (has links)
Ce travail est une réflexion prospective sur la densification verticale de la ville par la tour d'habitation. Trois échelles sont considérées : le bâtiment seul (objet), la composition de sa façade et son insertion urbaine (bâtiment situé). Le parti pris est de n'examiner que le seul critère énergétique. Sont réalisées trois séries d'études « morpho-énergétiques » : 1 - une étude sur l'influence énergétique de la morphologie d'un bâtiment « objet » : l'objectif est de développer un outil d'évaluation simplifiée de la performance énergétique totale des bâtiments résidentiels. 2 - une extension du précédent modèle en insérant le bâtiment dans un morceau de ville : l'objectif est d'identifier l'influence des configurations urbaines sur leur performances énergétiques, à l'aide d'un outil d'optimisation par algorithmes génétiques. 3 - l'étude d'une nouvelle démarche de conception et de rénovation des bâtiments à travers le concept Core-Skin-Shell : l'objectif est d'évaluer l'intérêt énergétique d'une décomposition fonctionnelle du bâtiment. / This thesis analyses the energy performance of dense cities and residential towers. It focuses on the energy performance of the built environment at three different scales – the building, the façade and the city area. The details of the three “morpho-energetic” studies are as follows : 1 - the first one analyses the link between buildings' dimensions and their energy performance: it focuses on a simple calculation method to quickly approximate the whole energy balance of residential buildings. 2 - the second study analyses the morphology of energy and density reasoned city areas: the ultimate goal is to develop a tool helping to find the optimal form(s) of a low energy and dense city area. It is based on a genetic algorithm tool. 3 - the last one analyses the energy impact of a new design methodology for construction and refurbishment: the Core-Skin-Shell concept.
166

Uma proposta de FSS fractal com geometria simplificada

Montalv?o, Emanuele da Silva Rodrigues 21 December 2010 (has links)
Made available in DSpace on 2014-12-17T14:55:47Z (GMT). No. of bitstreams: 1 EmanueleSRM_DISSERT.pdf: 2423953 bytes, checksum: 516a98f7f1136b2e57265165c2a43b20 (MD5) Previous issue date: 2010-12-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Frequency Selective Surfaces (FSS) are periodic structures in one or two dimensions that act as spatial filters, can be formed by elements of type conductors patches or apertures, functioning as filters band-stop or band-pass respectively. The interest in the study of FSS has grown through the years, because such structures meet specific requirements as low-cost, reduced dimensions and weighs, beyond the possibility to integrate with other microwave circuits. The most varied applications for such structures have been investigated, as for example, radomes, antennas systems for airplanes, electromagnetic filters for reflective antennas, absorbers structures, etc. Several methods have been used for the analysis of FSS, among them, the Wave Method (WCIP). Are various shapes of elements that can be used in FSS, as for example, fractal type, which presents a relative geometric complexity. This work has as main objective to propose a simplification geometric procedure a fractal FSS, from the analysis of influence of details (gaps) of geometry of the same in behavior of the resonance frequency. Complementarily is shown a simple method to adjust the frequency resonance through analysis of a FSS, which uses a square basic cell, in which are inserted two reentrance and dimensions these reentrance are varied, making it possible to adjust the frequency. For this, the structures are analyzed numerically, using WCIP, and later are characterized experimentally comparing the results obtained. For the two cases is evaluated, the influence of electric and magnetic fields, the latter through the electric current density vector. Is realized a bibliographic study about the theme and are presented suggestions for the continuation of this work / As Superf?cies Seletivas de Frequ?ncia (FSS) s?o estruturas peri?dicas em uma ou duas dimens?es que atuam como filtros espaciais, podendo ser formadas por elementos do tipo patches condutores ou aberturas, funcionando como filtros rejeita-faixa ou passa-faixa, respectivamente. O interesse no estudo das FSS tem crescido atrav?s dos anos, pois tais estruturas atendem a requisitos espec?ficos como baixo custo, dimens?es e pesos reduzidos, al?m da possibilidade de se integrar com outros circuitos de micro-ondas. As mais variadas aplica??es para tais estruturas t?m sido investigadas, como por exemplo, radomes, sistemas de antenas para avi?es, filtros eletromagn?ticos para antenas refletoras, estruturas absorvedoras, etc. V?rios m?todos t?m sido utilizados para a an?lise de FSS, dentre eles, o M?todo das Ondas (WCIP). S?o diversas as formas de elementos que podem ser utilizados em FSS, como por exemplo, os do tipo fractal, que apresenta uma relativa complexidade geom?trica. Este trabalho tem como objetivo principal propor um procedimento de simplifica??o geom?trica de uma FSS fractal, a partir da an?lise da influ?ncia dos detalhes (fendas) da geometria da mesma no comportamento da frequ?ncia de resson?ncia. De forma complementar ? mostrado um m?todo simples de ajustar a frequ?ncia de resson?ncia atrav?s da an?lise de uma FSS, que utiliza uma c?lula b?sica retangular, na qual s?o inseridas duas reentr?ncias e as dimens?es dessas reentr?ncias s?o variadas, tornando poss?vel o ajuste da frequ?ncia. Para isso, as estruturas s?o analisadas numericamente, utilizando o WCIP, e posteriormente s?o caracterizadas experimentalmente, comparando-se os resultados obtidos. Para os dois casos ? avaliada, a influ?ncia dos campos el?trico e magn?tico, este ?ltimo atrav?s do vetor densidade de corrente el?trica. ? realizado um estudo bibliogr?fico a cerca do tema e s?o apresentadas sugest?es para a continuidade deste trabalho
167

Desenvolvimento e caracteriza??o de solu??es tern?rias ?gua-glicerol-propilenoglicol como fluido refrigerante secund?rio / Development and Characterization of Ternary Solutions Glycerol-Propylene Glycol-Water like Secondary Coolant Fluid

Medeiros, Pedro Samuel Gomes 17 December 2012 (has links)
Made available in DSpace on 2014-12-17T14:58:19Z (GMT). No. of bitstreams: 1 PedroSGM_DISSERT.pdf: 2326508 bytes, checksum: 0470d41afc69c7b0199856916c484045 (MD5) Previous issue date: 2012-12-17 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Cada vez mais o mundo est? adotando uma matriz energ?tica limpa e sustent?vel, com o uso da agricultura para produ??o de agroenergia e combust?veis verdes, como bioetanol e biodiesel. A produ??o do biodiesel gera um coproduto, a glicerina, em que as usinas produtoras t?m dificuldades com o destino do seu excedente. V?rias pesquisas est?o sendo desenvolvidas para nortear diferentes usos do glicerol (glicerina pura). O glicerol possui total solubilidade com a ?gua e pode ser usado como aditivo anticongelante aplicado como fluido refrigerante secund?rio, em sistemas de refrigera??o indireta e com termoacumula??o. Tamb?m, o glicerol ? uma mat?ria-prima alternativa na produ??o de propilenoglicol, um ?lcool de grande aplicabilidade industrial inclusive como anticongelante. Por?m, o melhor ?lcool anticongelante ? o etilenoglicol, um ?lcool t?xico derivado do petr?leo. As solu??es ?gua-glicerol (AG) e ?gua-propilenoglicol (AP) possuem propriedades termof?sicas de qualidade inferior e desequilibradas se comparadas ?s solu??es ?gua-etilenoglicol (AE). Desta forma, esta pesquisa inovadora teve como prop?sito o desenvolvimento e a caracteriza??o de solu??es tern?rias ?gua-glicerol-propilenoglicol (AGP) como fluidos secund?rios, com propriedades termof?sicas desej?veis e competitivas com as solu??es ?gua-etilenoglicol. Equa??es preditivas simplificadas foram usadas para prever o comportamento das solu??es AGP, onde as seguintes propriedades termof?sicas foram avaliadas e estimadas teoricamente: ponto de congelamento, massa espec?fica, calor espec?fico e condutividade t?rmica. As concentra??es para definir o ponto de congelamento das solu??es AGP foram definidas a partir da Lei de Raoult das propriedades coligativas. A an?lise matem?tica inicial mostrou que as solu??es AGP possuem propriedades mais equilibradas que as solu??es AG e AP e competitiva com a solu??o AE. A comprova??o experimental das solu??es AGP foi feita a partir de ensaios para verificar suas propriedades (massa espec?fica, condutividade t?rmica e viscosidade din?mica), comparando com as solu??es de refer?ncia AG e AP. Os resultados experimentais comprovaram as expectativas iniciais e viabilidade t?cnica do novo fluido secund?rio tern?rio. A grande vantagem dos fluidos AGP ? que s?o at?xicos e derivam de fontes renov?veis
168

Evaluation of the coarse aggregate influence in the fatigue damage using fine aggregate matrices with different maximum nominal sizes / AvaliaÃÃo da influÃncia agregado graÃdo no dano por fadiga usando matriz de agregados finos com diferentes tamanhos mÃximas nominais

Reuber Arrais Freire 01 July 2015 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Fatigue cracking is one of the most common distresses in flexible pavements in Brazil and in the world. Fatigue damage in asphalt mixtures originates as a small scale phenomenon. Recently, some authors have used the fine portion of the asphalt mixtures, called Fine Aggregates Matrix (FAM), as an intermediate step to estimate the hot mix asphalt (HMA) behavior. By definition, the FAM is composed of fine aggregates, mineral filler and asphalt binder. There are many volumetric issues of these kind of mixtures. In Brazil, the developed research regarding FAM uses sieve #10 (2.00mm) in the FAM sample preparation, since the #16 sieve (most used in the literature) does not belong to the set of national standardized sieves. Recently, some authors have used the concept of continuum damage mechanics in viscoelastic media in order to quantify the damage during the fatigue testing. In this theory the cracks are considered homogeneous dispersed in the medium, and are represented from internal state variables, determined experimentally. The objective of this study is to evaluate the influence of the variation of one of the FAM constituents, the aggregates, by varying its Maximum Nominal Size (MNS), on damage resistance of these asphalt mixtures. To achieve the objective, Linear Amplitude Sweep (LAS) and time sweep (TS) tests at controlled stress and controlled strain modes of loading were performed on the mixtures and the results were analyzed using the simplified viscoelastic continuum damage (S-VECD) methodology creating C vs S curves. Through the results and a failure criterion based on energy, cyclic tests can be simulated at different loading conditions for WÃhlerâs curves construction. The FAM dynamic moduli obtained are very similar to the frequency used to induce damage. However, for lower frequency, the intermediate FAM presented lower stiffness value. It was concluded that FAM with different MNS present very distinct damage performance, and the decrease in the MNS results in an increase in the mixture damage performance for low strain amplitudes. Also, the LAS testing protocol does not allow failure prediction due to the absence of failure in this type of test for FAM. / O Trincamento por fadiga à um dos problemas mais comuns em pavimentos flexÃveis no Brasil e no mundo. Danos por fadiga em misturas asfÃlticas se origina como um fenÃmeno de pequena escala. Recentemente, alguns autores tÃm utilizado a porÃÃo fina das misturas asfÃlticas, chamado Matriz de Agregados Finos (MAF), como um passo intermediÃrio para estimar o comportamento do Concreto AsfÃltico (CA). Por definiÃÃo, a MAF à composta de agregados finos, fÃler mineral e ligante asfÃltico. Hà muitas questÃes volumÃtricas neste tipo de mistura. No Brasil, a pesquisa desenvolvida sobre MAF usa peneira #10 (2,00mm) na preparaÃÃo de amostras, uma vez que a peneira #16 (mais utilizado na literatura) nÃo pertence ao conjunto de peneiras normatizadas nacionalmente. Recentemente, alguns autores tÃm utilizado o conceito de mecÃnica do dano contÃnuo em meios viscoelÃsticos, a fim de quantificar o dano durante o ensaio de fadiga. Nesta teoria as trincas sÃo consideradas homogÃneas dispersa no meio, e sÃo representados como variÃveis ​internas ​de estado determinadas experimentalmente. O objetivo deste estudo à avaliar a influÃncia da variaÃÃo de um dos constituintes da MAF, os agregados, variando seu tamanho mÃxima nominal (TMN), na resistÃncia ao dano destas misturas asfÃlticas. Para alcanÃar o objetivo, ensaios de Linear Amplitude Sweep (LAS) e Time Sweep (TS) à tensÃo controlada e à deformaÃÃo controlada foram realizadas nas misturas e os resultados foram analisados ​​usando o mÃtodo simplified viscoelastic continuum damage (S-VECD) para a criaÃÃo de curvas C vs S. AtravÃs dos resultados e um critÃrio de falha com base em energia, os testes cÃclicos podem ser simulados em diferentes condiÃÃes de carregamento para a construÃÃo da curva de WÃhler. Os mÃdulos dinÃmicos obtidos das MAFs sÃo muito semelhantes aos da frequÃncia utilizada para induzir danos. No entanto, para menor freqÃÃncia, a MAF intermediÃria apresentou menor valor de rigidez. Concluiu-se que as MAFs com diferentes TMNs apresentaram desempenhos de dano muito distintos, e à diminuiÃÃo do TMN da mistura resulta em um aumento da resistÃncia ao dano para baixas amplitudes de deformaÃÃo. AlÃm disso, o protocolo de teste LAS nÃo permite a previsÃo de falha, devido à ausÃncia de falha neste tipo de ensaio para MAF.
169

Seleção de área para implantação de aterro sanitário simplificado: estudo de caso para o município de Guapó GO / Área selection for implamentation of simplified landfill - A case study for the city of Guapo - GO

MARQUES, Marília Daher 29 August 2011 (has links)
Made available in DSpace on 2014-07-29T15:01:48Z (GMT). No. of bitstreams: 1 Dissertacao Marilia Daher Marques.pdf: 3111241 bytes, checksum: 34783ea2d710ed7dd92ebe4c2b85a5df (MD5) Previous issue date: 2011-08-29 / The disposal of Municipal Solid Waste is one of the major sanitation problems found in Brazil. The disposal of these wastes in inappropriate places brings social, environmental and economic disorders. Currently the state of Goiás has extremely low rate of proper disposal of MSW, especially in small cities. Recent regulatory instructions of ABNT and of SEMARH GO brought simplified methodology for the construction of simplified landfill for municipalities with untill 50.000 inhabitants, considered as small municipalities. As those have simplified structure, the area selection for deployment of those landfills must be careful to avoid possible environmental and social damages. Therefore, this work aimed to select viable areas for implementation of simplified landfill having as scenario the city of Guapó GO. It was determined a project horizon of 20 years. The selection of viable areas was performed using the geographic information system (GIS) ArcGis 9.3, which was used to exclude unsuitable areas according to current legislation. In the first stage of the study were used shapes provided by the State System of Statistics and Geographic Information of the State of Goiás. Were identified five possible areas for the implementation of simplified landfill which were submitted for individual evaluation using weighting matrices in which the areas were evaluated and scored according to aspects required by environmental legislation. Done the hierarchy process was searched for the presence or absence of legal reserves in them. As a result we obtained the three best areas for the implementation of simplified landfill in the city of Guapó and concluded that the selection of viable areas that meets the legal parameters can and should be done by all small municipalities in order to adjust the final disposal of their MSW and promote the welfare of local people and the preservation of the environment. / A disposição final de Resíduos Sólidos Urbanos (RSU) é hoje um dos grandes problemas de saneamento básico encontrados no Brasil. O despejo destes resíduos em locais inadequados traz transtornos sociais, ambientais e econômicos. Atualmente, o Estado de Goiás possui baixíssimo índice de disposição adequada de RSU, principalmente nos municípios de pequeno porte. Recentes instruções normativas da ABNT e da SEMARH-GO trouxeram metodologia simplificada para a construção de aterro simplificado para municípios com até 50.000 habitantes, considerados como municípios de pequeno porte. Por possuírem estrutura simplificada, a seleção de área para implantação destes aterros deve ser criteriosa a fim de evitar possíveis danos ambientais e sociais. Diante disso, este trabalho teve o objetivo de selecionar áreas viáveis para implantação de aterro sanitário simplificado tendo como cenário de estudo o município de Guapó GO, o qual atualmente dispõe seus resíduos em aterro controlado. O horizonte de projeto determinado foi de 20 anos. A seleção das áreas viáveis foi realizada utilizando o sistema de informações geográficas (SIG) ArcGis 9.3, através do qual excluiu-se áreas inadequadas de acordo com a legislação vigente. Na primeira etapa do trabalho foram utilizadas shapes fornecidas gratuitamente pelo Sistema Estadual de Estatística e de Informações Geográficas do Estado de Goiás. Foram identificadas cinco possíveis áreas para a implantação do aterro sanitário simplificado, que foram submetidas à avaliação individual utilizando-se de matrizes de ponderação nas quais as áreas foram avaliadas e pontuadas de acordo com aspectos exigidos pela legislação ambiental vigente. Feita a hierarquização das áreas verificou-se a presença ou ausência de reservas legais nas mesmas. Como resultado obteve-se as três melhores áreas para a implantação do aterro sanitário simplificado do município de Guapó e constatou-se que a seleção de uma área viável, que atenda aos parâmetros e exigências legais, pode e deve ser realizada por todos os municípios de pequeno porte a fim de adequar a disposição final de seus RSU e promover o bem-estar da população local e a preservação do meio ambiente.
170

Modélisation et étude numérique d'écoulements diphasiques : Modélisation d’un écoulement homogène équilibré : Modélisation des collisions entre gouttelettes à l’aide d’un modèle simplifié de type BGK / Modeling and numerical study of two phases flow

Champmartin, Aude 28 February 2011 (has links)
Cette thèse décrit la modélisation et la simulation de systèmes à deux phases composées de particules évoluant dans un gaz. Les deux phases interagissent entre elles et le type de modèle à considérer dépend directement du type de simulations envisagées. Dans une première partie, les deux phases sont considérées comme des fluides, elles sont décrites à l’aide d’un modèle de mélange avec une relation de dérive (permettant de suivre une vitesse relative entre les deux phases et de prendre en compte deux vitesses) et sont supposées à l’équilibre en température et pression. Cette partie du manuscrit est composée de la dérivation des équations, de l’écriture d’un schéma numérique associé à ce jeu d’équations, d’une étude d’ordre de ce schéma ainsi que de simulations. Une étude mathématique de ce modèle (hyperbolicité dans un cadre simplifié, stabilité du système linéaire autour d’un état constant) a été réalisée dans un cadre o`u le gaz est supposé barotrope. La seconde partie de ce manuscrit est consacrée à la modélisation de l’effet de collisions inélastiques sur les gouttelettes lorsque l’on se place à un temps de simulation beaucoup plus court, pour lequel les gouttelettes ne peuvent plus être vues comme un fluide. Pour modéliser ces collisions, on construit un modèle simplifié (moins coûteux en temps) de type BGK permettant de reproduire le comportement en temps de certains moments sur les gouttelettes. Ces moments sont choisis pour être représentatifs de l’effet des collisions sur ces gouttelettes, à savoir une thermalisation en vitesse et énergie. Ce modèle est discrétisé avec une méthode particulaire et des résultats numériques sont donnés en comparaison avec ceux obtenus avec un modèle résolvant directement l’équation de Boltzmann homogène. / This thesis describes the modelisation and the simulation of two-phase systems composed of droplets moving in a gas. The two phases interact with each other and the type of model to consider directly depends on the type of simulations targeted. In the first part, the two phases are considered as fluid and are described using a mixture model with a drift relation (to be able to follow the relative velocity between the two phases and take into account two velocities), the two-phase flows are assumed at the equilibrium in temperature and pressure. This part of the manuscript consists of the derivation of the equations, writing a numerical scheme associated with this set of equations, a study of this scheme and simulations. A mathematical study of this model (hyperbolicity in a simplified framework, linear stability analysis of the system around a steady state) was conducted in a frame where the gas is assumed barotropic. The second part is devoted to the modelisation of the effect of inelastic collisions on the particles when the time of the simulation is shorter and the droplets can no longer be seen as a fluid. We introduce a model of inelastic collisions for droplets in a spray, leading to a specific Boltzmann kernel. Then, we build caricatures of this kernel of BGK type, in which the behavior of the first moments of the solution of the Boltzmann equation (that is mass, momentum, directional temperatures, variance of the internal energy) are mimicked. The quality of these caricatures is tested numerically at the end.

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