394 resultados para Estradas vicinais


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Dissertação para a obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Vias de Comunicação e Transportes

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Nowadays there is a huge evolution in the technological world and in the wireless networks. The electronic devices have more capabilities and resources over the years, which makes the users more and more demanding. The necessity of being connected to the global world leads to the arising of wireless access points in the cities to provide internet access to the people in order to keep the constant interaction with the world. Vehicular networks arise to support safety related applications and to improve the traffic flow in the roads; however, nowadays they are also used to provide entertainment to the users present in the vehicles. The best way to increase the utilization of the vehicular networks is to give to the users what they want: a constant connection to the internet. Despite of all the advances in the vehicular networks, there were several issues to be solved. The presence of dedicated infrastructure to vehicular networks is not wide yet, which leads to the need of using the available Wi-Fi hotspots and the cellular networks as access networks. In order to make all the management of the mobility process and to keep the user’s connection and session active, a mobility protocol is needed. Taking into account the huge number of access points present at the range of a vehicle for example in a city, it will be beneficial to take advantage of all available resources in order to improve all the vehicular network, either to the users and to the operators. The concept of multihoming allows to take advantage of all available resources with multiple simultaneous connections. This dissertation has as objectives the integration of a mobility protocol, the Network-Proxy Mobile IPv6 protocol, with a host-multihoming per packet solution in order to increase the performance of the network by using more resources simultaneously, the support of multi-hop communications, either in IPv6 or IPv4, the capability of providing internet access to the users of the network, and the integration of the developed protocol in the vehicular environment, with the WAVE, Wi-Fi and cellular technologies. The performed tests focused on the multihoming features implemented on this dissertation, and on the IPv4 network access for the normal users. The obtained results show that the multihoming addition to the mobility protocol improves the network performance and provides a better resource management. Also, the results show the correct operation of the developed protocol in a vehicular environment.

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Roads represent a new source of mortality due to animal-vehicle risk of collision threatening log-term populations’ viability. Risk of road-kill depends on species sensitivity to roads and their specific life-history traits. The risk of road mortality for each species depends on the characteristics of roads and bioecological characteristics of the species. In this study we intend to know the importance of climatic parameters (temperature and precipitation) together with traffic and life history traits and understand the role of drought in barn owl population viability, also affected by road mortality in three scenarios: high mobility, high population density and the combination of previous scenarios (mixed) (Manuscript). For the first objective we correlated the several parameters (climate, traffic and life history traits). We used the most correlated variables to build a predictive mixed model (GLMM) the influence of the same. Using a population model we evaluated barn owl population viability in all three scenarios. Model revealed precipitation, traffic and dispersal have negative relationship with road-kills, although the relationship was not significant. Scenarios showed different results, high mobility scenario showed greater population depletion, more fluctuations over time and greater risk of extinction. High population density scenario showed a more stable population with lower risk of extinction and mixed scenario showed similar results as first scenario. Climate seems to play an indirect role on barn owl road-kills, it may influence prey availability which influences barn owl reproductive success and activity. Also, high mobility scenario showed a greater negative impact on viability of populations which may affect their ability and resilience to other stochastic events. Future research should take in account climate and how it may influence species life cycles and activity periods for a more complete approach of road-kills. Also it is important to make the best mitigation decisions which might include improving prey quality habitat.

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We take for granted that we exist in dimensions of time and space. We accept that time passes and that space extends as a matter of course. Just as our personal space is important to us, so is time of our own. The individual is capable of developing a variety of time perspectives or orientations, each applicable to a different aspect of life, for instance, home, leisure, economic, political and organisational. Our temporal perspective influences a wide range of psychological processes, from motivation, emotions and spontaneity to risk-taking creativity and problem-solving. Our temporal landscapes are made up of recognisable domains, with permeable borders – private time and public time, home time and work time, past, present and future time, cyclical time. Just as a geography of space contains recognisable natural features – rivers, deserts, mountains – and features created by human beings – canals, roads, skyscrapers – so our temporal landscape contains natural features – day and night, the seasons – and features created by us – the ordering of social, economic, legal, and organisational time into, among others, the practices of family life, financial periods, prison sentences and workloads. This paper views the temporal landscapes of night nurses, and is based on longitudinal ethnographic research. It highlights areas such as shift work, workload, and the temporal aspects of caring. The result is the production of a map, albeit a rough one, of the temporal landscape inhabited by night nurses as they go about their working lives.

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As estradas e tráfego inerente surgem como a criação antrópica mais conspícua e penetrante na paisagem natural, sendo considerados os principais agentes causadores de fragmentação e destruição de habitats, assim como representam um obstáculo físico sem precedentes, limitando as relações directas entre os indivíduos, por diminuição da frequência de dispersão e aumento da mortalidade por atropelamento, impedindo o fluxo natural de genes e suscitando o aumento de fenómenos de inbreeding e perda de heterozigotia. Todos os impactes deletérios associados às rodovias são claramente perceptíveis em vertebrados, onde as aves de rapinas nocturnas não são excepção. Uma vez que estas rapaces beneficiam das suas bermas e orlas, como locais de poiso, nidificação ou como corredores de dispersão através da paisagem, são frequentemente vítimas de mortalidade por atropelamento em estradas, sendo esta problemática considerada actualmente uma das mais recentes e importantes formas de mortalidade não natural em rapinas nocturnas e vinculada como um dos maiores problemas de conservação que afecta este grupo. Não obstante, esse mútuo efeito de atracção/repulsa das estradas a estas rapaces, as rodovias criam uma barreira específica que limita a dinâmica, comportamento e densidade populacional das espécies residentes, reconhecendo-se que o isolamento daí resultante, pode comprometer a viabilidade populacional a longo prazo, podendo mesmo conduzir a altos riscos de extinção das populações locais devido a efeitos estocásticos. Mediante esta problemática, este trabalho debruçou-se sobre um único objectivo principal: a avaliação do impacte das rodovias e do tráfego, na densidade das aves de rapina nocturnas. Este estudo foi efectuado na região Alentejana, abrangendo uma área de cariz tipicamente mediterrânico, delimitada pelas localidades de Montemor-o-Novo, Arraiolos e Évora, sendo seccionada por 143 quilómetros de estradas, divididas em autoestrada, rodovias com elevada e reduzida densidade de tráfego. A monitorização das rapinas nocturnas foi conduzida em dois anos amostrais (2005 e 2007), tendo sido focalizada sobretudo em duas espécies de Strigiformes, a Coruja­ do-mato Strix aluco e o Mocho-galego Athene noctua, recorrendo ao uso de playbacks com reprodução de vocalizações de indivíduos conspecíficos. Foram usadas 32 variáveis explicativas integradas em três grandes grupos: variáveis de estrada, métricas da paisagem, uso do solo, tendo sido analiticamente testadas, recorrendo à aplicação de Modelos Lineares Generalizados. Os principais resultados obtidos demonstram que as variáveis de estrada, aliadas à densidade de tráfego e ruído inerente à sua circulação, são provavelmente, responsáveis por um comportamento de repulsa das espécies de aves de rapina nocturnas em estudo, apresentando estas densidades mais elevadas longe de áreas antropicamente perturbadas e, portanto, de menor qualidade que se encontram adjacentes às rodovias. Todavia a presença de habitat favorável a estas rapaces é provavelmente o descritor com maior poder estatístico no que concerne à sua distribuição e densidade, sendo os montados densos e a presença de zonas agrícolas de sequeiro, positivamente correlacionadas, respectivamente com a densidade de casais reprodutores de Coruja-do-mato e Mocho-galego. Mediante a observação dos resultados será veemente a aplicação de medidas de mitigação específicas, que fundamentalmente considerem o afastamento dos efectivos populacionais longe das estradas e tráfego, conservando e assegurando as características estruturais, requisitos e qualidade dos habitats, de modo a incrementar e garantir a viabilidade e densidade das populações, fidelizando a territorialidade e permanência destas aves nestas áreas. Adicionalmente deverá investir-se na conectividade das manchas de paisagem fragmentada pelas rodovias, criando opções de conservação estratégicas, em zonas ecologicamente mais sensíveis, que não somente minimizem o efeito de repulsa reconhecido nestas aves, mas também os níveis de mortalidade por atropelamento, tornando os ecossistemas mais funcionais para a sobrevivência destes rapaces. ABSTRACT; Roads and traffic are the most conspicuous and pervasive human creation, being the great responsible for fragmentation and habitats destruction, reducing animal movement through landscape, which implies decrease of gene flow and loss of variability that can fragmented populations, thus reducing their sizes and densities. All deleterious impacts associated with roads are clearly visible in vertebrates, where owls aren't exception, being frequent victims of road mortality, since they can use roadside habitats and edges for hunting, nesting or dispersal corridors through the landscape, being nowadays one of the most recent and important causes of non­natural mortality in owls and has been recognized as one of the largest conservation problems affecting this group. However, the attractive and avoidance effect of roads and his edges on owls creates a barrier effect that limits dynamics, behaviour and breeding density of resident species, recognizing that possible isolation, could compromise populations survival, make them more vulnerable to high risks of local extinction due to stochastic effects. Despite that, several authors suggest that owls use roads to hunt, as marginal habitats, or for navigation corridors through the landscape ln this context, the major aims of this study was to verify if there are negative effects of roads on the density of owls, considering traffic as an influencing factor. This study was conducted in Alentejo, covering a typical Mediterranean area, including three main localities Montemor-o-Novo, Évora and Arraiolos, being sectioned by 143 km of roads, including highway, roads with high traffic density, and the remaining with low traffic density. The owl census was conducted in two sampling years (2005 and 2007) and was focused mainly on Little owl Athene noctua and Tawny Owl Strix aluco species, using the playback technique, with conspecific calls. We used 32 explanatory variables, mainly included in three groups: road variables, landscape metrics and land use, having been analytically tested, with application of Generalised Linear Models. The main results show that noisy roads with high traffic density are probably the most responsible for the avoidance behaviour of owls, under the study area, showing density depression near high anthropogenic disturbed areas adjacent to roads. However, the presence of habitat quality to these birds is probably the descriptor with greater statistical power, considering its distribution and density, with the dense oak woodland and croplands and arable lands, positively correlated, respectively with Tawny owl and Little owl density. ln consequence, the great conservation effort should be done in order to keep breeding populations away from roads and traffic, ensuring the structural features, requirements and quality of its habitats in order to enhance and ensure the viability and density of owl's populations in these areas. ln addition, it is important to invest in connectivity between roadside fragmented patches, creating strategic conservation options, in sensitive areas, which minimize the avoidance effect, recognized in owls, but also road-kill levels, making ecosystems more functional to survival of these top predators.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, Programa de Mestrado Profissional em Matemática em Rede Nacional, 2015.

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O presente estudo foi realizado numa área com 156,5 Km/ localizada nos municípios de Évora e Montemor-o-Novo, a Sul de Portugal. Cinco genetas foram seguidas via telemetria durante seis meses visando o estudo do uso do espaço e comportamento relativamente às estradas. Estas, parecem funcionar como limites das áreas vitais da geneta actuando como barreira física e/ou social aos seus movimentos. Contudo, as genetas cruzaram diferentes tipos de estrada embora com frequência reduzida. Por outro lado, as genetas adoptaram uma distância de segurança média das estradas, de 1km, onde se verifica uma aproximação durante a noite e um distanciamento durante o dia. Todos os animais evidenciaram ter uma distribuição não aleatória relativamente às estradas concentrando-se maioritariamente apenas num dos lados da estradão que indica o efeito destas infra-estruturas como barreiras parciais ao movimento. A presença de galerias ripicolas parece promover o uso das bermas e durante o estudo todos os indivíduos seleccionaram positivamente estes habitats. ABSTRACT: The present study, was conducted in a 156,5 Km 2 area, located in the Évora and Montemor-o-Novo counties, southern Portugal. Five genets were radio-tracked for six months with the purpose of studying their space use and behavior towards roads. ln this study, roads seem to be artificial boundaries to genets' home ranges acting as physical and social barrier to their movements. However, genets have crossed different types of roads, although in lower frequencies. They adopted, in average, a security distance of 1km from roads being further during the day and closer at night. Ali animals showed a not random distribution on their activity concerning roads presence and their localizations tend to concentrate on one side of the road which confirms that these infrastructures pose a significant barrier to genets' movements. The existence of riparian galleries seems to promote roadside usage and during the study genets have selected positively these habitats.

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According to many scientists third industrial revolution has already began and this primarily means the transition to renewable energy sources. Energy requirements are increasing rapidly due to fast industrialization and the increased number of vehicles on the roads. Massive consumption of fossil fuels leads to environmental pollution, therefore, biofuels are offered as an alternative. For example, the application of biodiesel in diesel engines instead of diesel results in the proven reduction of harmful exhaust emissions. One of the most important technologies, which has been already explored at the commercial level, is the production of a liquid biofuel applicable in compression-ignition engines (or diesel engines), from biomass rich in fats and oils. This biofuel is generically referred as biodiesel, and consists essentially of a mixture of FAME's (fatty acid methyl esters). This current work describes modern approaches of biodiesel production from vegetable oil and subsequent analysis of produced biodiesel main characteristics such as density, acidity, iodine value and FAME content.

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The ceramics industry in Piauí is nowadays with 55 industries where 11 are in Teresina which is the mainstream of the state, producing 55 million shingles; in which 10 % is of this production is wasted being sometimes thrown on the margins of rivers, roads and highways provoking an environmental degradation. The main goal of this work is to verify the potential of producing semi porous ceramic using grog of shingles, on the first part of this work bodies-of-proof were produced from a basic formula of an industry, doping it with 5 %, 10 %, 15 % and 20 % in mass and in the second part of this work some bodies-of-proof were produced from a formula where one raw material was substituted by 50 % of grog and another substituting it all by grog, bodies-of-proof made of a basic formula previously announced was used for experiment control.The grog and the raw materials were characterized by: particle size analysis , thermal differential analysis, X ray diffraction , X ray fluorescence, an thermal gravimetric analysis and rational analyses. The bodies-of-proof were sintetisized in an industrial oven obeying the normal cycle adopted by an industry, with peak temperatures of 1135 oC and a fast burning cycle of 25 minutes having as energetic fuel liquefied petroleum gas . The pieces that were obtained by this were submersed in rehearsed physics of: water absorption of, apparent specific mass, apparent porosity, lineal retraction, rupture tension to the flexural and dilatometry; mineralogical analysis for X ray diffraction; and microstructural for electronic microscope of sweeping. For all the formulas with addition of grog, superior priorities to the requested by the requirements for semi porous and for the formula to F2-2,5 superior priorities to standard formulas which justifies the incorporation of the shingles in mass for the semi porous ceramic

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Mestrado em Finanças

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Droughts surfaced in 1877 as a crucial problem for the birthing Brazilian nation. Engineers, who formed the country's technical and scientific elite, took it upon themselves to study, understand and fight the problem through planned actions of intervention on space. This work, based on proposals and discussions contained in engineering magazines and reports, aims to provide elements for the comprehension of how these systematized actions against droughts, in the Iate nineteenth and early twentieth century, contributed to spatial analysis and the formation of a (then-inexistent) regional and territorial planning discipline in Brazi!. Engineers, by taking up the position of masterminds in the country's modernization, guaranteed for themselves personal economic stability, social prestige and political power. By understanding nature, either as a resource to be exploited or an adversary to national progress, they contributed to the delimitation of the region now known as the Northeast. By seeking to understand the drought phenomenon, they created knowledge about the space they sought to intervene on; by constructing their projects amid political and economical difficulty, they changed the organizational structures of cities and country in the northeast. The proposals for açudes (Iarge water reservoirs) allowed the fixation of population and the resistance against droughts; the roads - railroads and automotive roadways - connected the sertão to the capitais and the coast, speeding up help to the affected populations during droughts and allowing the circulation of goods so as to strengthen the local economies in normal rimes. The adopted practices and techniques, adapted from foreign experience and developed through trial and improvement, were consolidated as an eminently spatial intervention course, even if a theoretical body of regional or territorial planning wasn't formed in Brazil. Regional Planning proper was first applied in the country in the Northeast itself, in the 1950s, based off an economical view of reality in order to achieve development. The engineer's work prior tothat date, however, cannot be dlsconsldered. It was proved that, despite facing financial and political hurdles, engineers had a profound commitment to the problem and intended to act systematically to transform the economical and social relations in the region, in order to be victorious in their struggle against droughts

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The railroad, from 1870 and on, becomes an usual complaining in the press s and politician elite s speeches, especially because of Natal s geographic isolation. The implantation of two railroads in the capital territory Estrada de Ferro de Natal a Nova Cruz, afterwards part of Great Western Railway Company network, and Estrada de Ferro Central do Rio Grande do Norte had serious implications in the urban environment. While railroad s structures were already consolidated, other transportation mechanisms were being implanted in the first decades of the 20th century, such as trams lines, which, by the way, was a transport modal that also used rails as a dislocation meaning. Considering these questions, we may ask: how come railroads and tramways demands, roads and buildings had influenced the internal organization of Natal? We work with the general hypothesis that the influence of technical networks, composed by tramways and railroads, over Natal s urban space happened in a diversified way, sometimes consolidating social aspects in certain areas, sometimes improving the occupation of others. The impact over the city s territory also happens in a diversified way between the buildings/railroad s complexes and the pathways. The different scale of the train in comparison to the trams velocity, size, noise level, flow, among others is also a cause to the different consequences in urban environment. The main objective of this work is to understand the role of circulation technical networks in the construction process of urban space in Natal, as a way to contribute to the urban historiography about the subject. The time frame adopted, between 1881 and 1937, marks the time path of railroads and tramways in Rio Grande do Norte: 1881 is the year of railroad s first section inauguration from Natal to São José do Mipibu as well of the railroad complex in the Republic Square in Natal; the year of 1937 marks the beginning of tramways declination process in the city. At this time railroads and tramways had to face more intensively the competition of motor vehicles. The theory reference adopted is based on concepts and analysis of authors, such as Flávio Villaça and Roberto Lobato Corrêa references to the concepts of urban structure , localization and accessibility and Gabriel Dupuy to explain the concept of urban technical networks . These references reveal the conflict of different realities in the urban universe interests and values which is an important factor about the construction of urban space. The information sources used were from two distinctive natures: primary, journals of the time studied and official government reports, and secondary, based on other works about the subject. It was also used by this study iconographic source, especially images from the data base of the research group História da Cidade, do Território e do Urbanismo .

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Mestrado em Arquitetura Paisagista - Instituto Superior de Agronomia - UL

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Avaliámos a importância das bermas das estradas como áreas de refúgio para pequenos mamíferos, em paisagens Mediterrânicas intensivamente pastoreadas, e comparámos esta possível função das estradas como refúgio com o papel fundamental das galerias ripícolas como reservatórios de diversidade biológica. Para esse efeito, foram realizadas capturas de micromamíferos em dois segmentos de estrada e em duas ribeiras da região de Évora. Foram capturados 457 indivíduos de cinco espécies diferentes. Mus spretus foi a espécie mais capturada, seguida de Crocidura russula e Apodemus sylvaticus. M. spretus apresentou uma maior abundância nas bermas de estrada do que na vegetação ripicola, enquanto que a abundância de C. russula e A. sylvaticus era semelhante para ambos os habitats. O número de capturas das três espécies foi bastante superior dentro dos habitats lineares do que na matriz circundante. Os indivíduos de M. spretus eram maiores nas ribeiras, mas significativamente menores fora dos habitats lineares, e os indivíduos de C. russula apresentavam uma melhor condição corporal nas bermas das estradas. Tanto as estradas como as ribeiras exerceram um forte efeito de barreira aos movimentos dos micromamíferos. Concluímos então que as bermas das estradas actuam como habitat de refúgio em áreas sub-óptimas das paisagens Mediterrânicas. ABSTRACT: We assessed the importance of road verges as refuge areas for small mammals, in highly intensified grazed pastures on a Mediterranean landscape, and compared road function as refuge with the fundamental role of riparian galleries as reservoirs of biological diversity. For this purpose, a small mammal trapping study was undertaken on road verges and on small stream sides. We sampled two road segments and two streams in the vicinity of Évora, Portugal. We captured a total of 457 individuals of five different species. Mus spretus was the most common species captured, followed by Crocidura russula and Apodemus sylvaticus. M. spretus was more abundant on road verges than on riparian strips, whilst the abundance of C. russula and A. sylvaticus were similar in the two habitats. Captures of the three species were much higher inside both linear habitats than on the surrounding matrix. M. spretus were bigger on stream sites but significantly smaller outside the linear habitats and C. russula had better body conditions on roads. 8oth roads and streams exerted a strong barrier effect to small mammals' movements. We conclude that roadside verges act as refuge habitat in sub-optimal Mediterranean landscapes.

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At a time of changes on the territory during the 19th century, the political and socioeconomic elites of the province and later State of Rio Grande do Norte evolved a discourse in order to justify the permanence of Natal as a city holding a status of capital. In this work we analyze the means employed by the ruling classes to impose their wish to raise Natal to an outstanding position among the existing cities by intervening on the territory during a period of one hundred years (1820-1920). During that time, which was characterized by changing commercial flows and technological development, the elites interventions were essentially directed to the implementation of modes of transportation, especially the railway. We try to understand the reinforcement of Natal as a capital city not only in political and administrative terms, but mainly in a commercial and symbolic manner, through the discourse and interventions undertaken by the local administrative elites, who stimulated the creation of a set of relations on the territory that also imprinted visible marks in the capital s urban fabric. These interventions were based upon the establishment of an infrastructure for exporting the State s production, firstly through and despite the Potengi River, and later on by the construction of railways. Although the project of Natal s hegemony had been outlined before the establishment of the railway network, in both cases the ultimate objective was to reinforce and develop the capital city as a commercial urban center to the detriment of other cities