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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

Efeito de pertubações antrópicas crônicas sobre a diversidade da flora lenhosa da caatinga

RIBEIRO, Elâine Maria dos Santos 25 February 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-15T14:44:30Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Elâine_Ribeiro_TESE_PPGBV.final_V2.pdf: 8805946 bytes, checksum: 49c5072b57c8b0d0264ac0e02e425dc3 (MD5) / Made available in DSpace on 2016-07-15T14:44:30Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Elâine_Ribeiro_TESE_PPGBV.final_V2.pdf: 8805946 bytes, checksum: 49c5072b57c8b0d0264ac0e02e425dc3 (MD5) Previous issue date: 2015-02-25 / FACEPE / Este estudo teve como objetivo investigar quais os efeitos de perturbações antrópicas crônicas (e.g. coleta de madeira e de produtos florestais não madeireiros, pastoreio extensivo, caça e danos causados à vegetação pela introdução de espécies exóticas que ocorrem em áreas remanescentes de floresta) sobre a diversidade taxonômica e filogenética da flora lenhosa da Caatinga. Inicialmente, investigamos como se dá a questão da perturbação crônica da flora e seus efeitos sobre a biodiversidade através da revisão de 51 artigos que tratam do tema. Verificamos que estes estudos, em sua maioria, foram realizados em países em desenvolvimento, cujas populações humanas utilizam a floresta para subsistência e comércio. Os efeitos da perturbação foram acessados principalmente ao nível de populações e comunidades, sendo a coleta de produtos florestais não madeireiros a fonte de impacto mais analisada. Os efeitos sobre a biodiversidade foram em geral negativos, mas efeitos neutros e positivos também foram registrados. O segundo capítulo traz um estudo de caso que verifica a influência das perturbações humanas crônicas sobre a diversidade e composição taxonômica da flora lenhosa da Caatinga, realizado em várias propriedades privadas na cidade de Parnamirim-PE, Brasil. Neste estudo foram amostradas comunidades lenhosas de adultos, jovens e plântulas, e como preditores da perturbação crônica utilizaram-se a densidade de pessoas e animais domésticos (caprinos e bovinos), além de indicadores de acessibilidade às áreas, como a distância ao centro urbano mais próximo, à estrada mais próxima e à propriedade rural mais próxima às parcelas amostradas. Esses preditores tiveram em geral efeitos negativos sobre a diversidade taxonômica independente do estágio ontogenético, sendo a densidade de pessoas e de animais os preditores mais importantes desses efeitos. Verificouse ainda que a composição das espécies nas áreas perturbadas foi distinta, sendo pouco representada pela abundância de espécies de madeira densa nas áreas mais perturbadas. O terceiro e último capítulo verificou como as comunidades lenhosas de adultos, jovens e plântulas da Caatinga, amostradas no capítulo anterior, são afetadas pela perturbação crônica do ponto de vista de diversidade e estrutura filogenética. Neste capítulo, utilizaram-se os mesmos preditores da perturbação citados anteriormente, porém agora combinados em um índice de perturbação crônica. A diversidade de famílias esperadas para história evolutiva da região e a distância média entre os indivíduos dessas comunidades, medida em anos, foi reduzida em ambientes mais perturbados e para todos os estágios ontogenéticos. As comunidades de jovens e de plântulas apresentaram maior grau de parentesco em áreas mais perturbadas, sendo os táxons Euphorbiaceae e Cnidoscolus responsáveis por esse aumento de parentesco. Os resultados desta tese demonstram que as perturbações antrópicas crônicas na Caatinga não podem ser negligenciadas, pois conferem efeitos negativos importantes à diversidade taxonômica e filogenética da flora lenhosa. Dessa forma, estratégias de manejo que conciliem o uso dessas florestas e a manutenção da biodiversidade da Caatinga são urgentes. / The aim of this study was to investigate the effect of chronic anthropogenic disturbances (e.g. harvesting of timber and non-timber forest products, hunting, livestock, and damage to vegetation caused by exotic species that occur in natural remnant forests) on the taxonomic and phylogenetic diversity of wood flora from Brazilian Caatinga. Initially, 51 scientific papers were revised in order to investigate how chronic anthropogenic disturbances affect the flora of natural ecosystems. Most studies were conducted at developing countries, where human populations use forest resources for subsistence and commerce. Chronic disturbance effects were accessed mainly at population and community levels, and harvesting of nontimber forest products was the disturbance source more frequently analyzed in those papers. Effects of the chronic disturbances were in general negative, however positive and neutral effects were also documented. The second chapter brings a case study that evaluates the influence of chronic disturbances on the taxonomic diversity and composition of Caatinga wood flora from private propreties at the municipality of Parnamirim-PE, Brazil. Adult, sapling and seedling of wood plant communities were sampled, and the density of people and livestock (goats and catle) near the plot were used as predictors of chronic disturbance, as well as the distances to the nearest urban centre, road and rural property. In general, these disturbance predictors showed negative effects on taxonomic diversity irrespective to ontogenetic stage. Moreover, the density of people and livestock near the plot were the main predictors of these negative effects. Species composition differed between plots with low and high level of disturbance, especially in relation to hard wood species, which were rare in the plots highly disturbed. The third and last chapter analyzed how the adult, sapling and seedling communities, surveyed previously, were affected by chronic disturbances from the viewpoint of the phylogenetic diversity and structure. In this chapter the chronic disturbance predictors described above were combined into a chronic disturbance index. The diversity of families expected to the local evolutionary history and the mean phylogenetic distance between the individuals were reduced in plots with higher level of disturbance for all ontogenetic stages. Sapling and seeedling communities had higher degree of relatedness in most disturbed sites, being Euphorbiaceas and Cinidoscolus taxa responsible for this increasing in the relatedness degree. Overall, this thesis demonstrates that chronic anthropogenic disturbance at Caatinga could not continue to be neglected, as it imposes deleterious effects to the taxonomic and phylogenetic diversity of wood plant assemblages. Management strategies conciliating forest use and the maintenance of Caatinga biodiversity are urgent.
162

Experimental studies of the muonic component of extensive air showers / Estudos experimentais da componente muônica de chuveiros atmosféricos extensos

Raul Ribeiro Prado 20 April 2018 (has links)
Ultra-High Energy Cosmic Rays (UHECR) can only be measured by the detection of Extensive Air Showers (EAS) created by the interaction of the cosmic ray particle with an atmospheric nuclei. The inference of some of the properties of UHECR, like their mass composition, is only possible by the comparison of measurements of EAS observables to predictions from Monte Carlo simulations. The most important source of uncertainties on the description of EAS by the simulations is the modeling of hadronic interactions. For many years it has been known that the hadronic interaction models fail on predicting the EAS observables related to their muonic component. The most evident manifestation of that is called muon deficit problem due to the fact that the number of muons in EAS with energies above 1018 eV predicted by simulations is smaller than the observed ones. The aim of this thesis is to approach this problem in three distinct fronts. First, a method is developed to interpret measurements of number of muons in terms of cosmic rays composition in despite of the muon deficit problem. Second, an EAS observable which is sensitive to the muon energy spectrum at ground and, consequently, can be used to constrain hadronic interaction models is proposed and tested. Third and final, the muon production in air showers is studied through measurements of hadron production spectra in pion-carbon interactions. / Raios Cósmicos Ultra Energéticos (Ultra-High Energy Cosmic Rays, UHECR) somente podem ser medidos através da detecção dos Chuveiros Atmosféricos Extensos (Extensive Air Showers, EAS) criados pela interação do raio cósmico primário com núcleos atmoféricos. A inferência de algumas propriedados dos UHECRs, como a composição de massa, é possível somente através da comparação entre medidas de observáveis dos EASs com predições geradas por simulações de Monte Carlo. A fonte de incerteza mais importante na descrição de EAS por simulações é a modelagem das interações hadrônicas. Por muitos anos é sabido que os modelos de interação hadrônica falham na predição de observáveis dos EASs relacionados a sua componente muônica. A manifestação mais evidente disso é chamada problema do déficit de múons devido ao fato que o número de múons em chuveiros com energias acima de 1018 eV predito por simulações é menor que os observados. O objetivo desta tese é abordar este problema através de três frentes. Primeiramente, um método é desenvolvido para interpretar as medidas do número de múons em termos de composição de raios cósmicos considerando o problema do déficit de múons. Segundo, a proposta e o teste de um observável que é sensível ao espectro de energia dos múons na superfície e, consequentemente, pode ser usado para discriminar entre os modelos de interação hadrônica. Por último, a produção de múons em chuveiros é estudada através de medidas do espectro de produção de hádrons em interações do tipo píon-carbono.
163

Avaliação do potencial de uso de três espécies vegetais como cobertura leve de telhados em edificações / Evaluation of the potential use of three plant species as light cover on roof buildings

Caio Cury Beatrice 12 August 2011 (has links)
O uso telhados verdes oferece benefícios como: moderação dos valores da temperatura no interior de edificações e contenção temporária da água de chuva, limpeza de poluentes atmosféricos, além de favorecer aspectos ecológicos. Poucos estudos científicos foram realizados no sentido de adaptar as técnicas contemporâneas e a indicação de espécies apropriadas ao sistema de telhado verde extensivo, originadas de regiões de clima temperado para as condições dos climas tropicais. O objetivo desta pesquisa foi identificar espécies com potencial de uso em telhado verde em sistema extensivo, quantificando a reação das plantas à variação de diferentes profundidades de substrato, em situações limitadas de manutenção, no aspecto de irrigação e nutrição do solo. Procurou-se também registrar o comportamento térmico do solo, a fim de verificar a influência da vegetação no aquecimento da parte inferior do solo em relação a distintas profundidades de substrato. Os vegetais foram plantados em setembro de 2009 aplicados em 27 plataformas de teste. Foram cultivadas três espécies de plantas das famílias Fabaceae (Arachis repens Handro), Poaceae (Paspalum notatum Flügge) e Ruscacea (Ophiopogon japonicus (L.F. Ker Gawl)), sob três tratamentos de profundidades de substrato, 0.05, 0.075 e 0.10 m. Quantificou-se mensalmente a porcentagem de cobertura vegetal, crescimento vertical e de sobrevivência, com encerramento ao final de um ciclo anual. O comportamento térmico dos solos nos diferentes tratamentos foi registrado automaticamente por meio de sensores. Os resultados indicaram a espécie Ophiopogon japonicus, em solos de 0.10 m, como a que apresentou o melhor desempenho entre as três examinadas, seguida por Paspalum notatum. Todas as espécies cultivadas em solos de 0.10 m apresentaram resultados satisfatórios quanto a cobertura do solo, crescimento vertical e sobrevivência, em relação ao cultivo em profundidades menores de substrato. O cultivo em menor profundidade de solo (0.05 m) revelou baixo valor de sobrevivência para todas as espécies durante o período de poucas chuvas. O crescimento vertical foi satisfatório para todas as espécies analisadas, dispensando manutenção com poda regular. Os resultados de comportamento térmico indicaram melhor desempenho de solos à profundidade de 0.10 m, independente do tipo de planta cultivado. Concluiu-se que solos de menor espessura são mais dependentes de cobertura vegetal para minimizar seu aquecimento e que os solos de maior espessura o fazem com menor dependência da vegetação. O melhor desempenho térmico foi observado em solos de 0.10 m, em relação às profundidades menores, embora não variasse seu comportamento térmico significativamente com o cultivo das três diferentes espécies de plantas, referente aos valores de cobertura atingidos neste experimento. / The uses of green roofs provide benefits such as moderation of the temperature inside buildings, temporary containment of rainwater, cleaning of air pollutants, in addition to promoting ecological aspects. Few scientific studies have been conducted to adapt contemporary techniques and indication of appropriate species for extensive green roof system, originated from temperate regions to the conditions of tropical climates. The objective of this research was to identify species with potential for use in green roof in the extensive system, quantifying the response of plants to variation of different depths of substrate, in limited situations of maintenance in respect of irrigation and soil nutrition. Was searched register the thermal behavior of soil in order to determine the influence of vegetation on the warming of the lower soil depths for different substrates. The plants were planted in september 2009, applied in 27 platforms. There were three species of cultivated plants of the families Fabaceae (Arachis repens Handro), Poaceae (Paspalum notatum Flügge) and Ruscacea (Ophiopogon japonicus (L.F.) Ker Gawl) under three treatments of substrate depths, 0.05, 0.075 and 0.10 m. Was quantified the percentage of monthly vegetation cover, vertical growth and survival, with closing at the end of an annual cycle. The thermal behavior of soils under different treatments was recorded using sensors. The results indicated that Ophiopogon japonicus in 0.10 m soils, showed the best performance among the three examined. All species grown in 0.10 m of soils had been satisfactory results of soil cover, vertical growth and survival in relation to culture in shallower substrate. The species Arachis repens showed the highest sensitivity to the depth and water stress during the autumn and winter, requiring more necessity of maintenance. Cultivation in shallower soil (0.05 m) showed low survival value for all species during the short rains. The vertical growth was satisfactory for all species analyzed, of which the greatest height reached was Ophiopogon japonicus without requiring regular maintenance pruning. The results indicated better performance thermal behavior of soil to a depth of 0.10 m, regardless of the type of plant grown. It was concluded that soils of lesser thickness are dependent on vegetation cover to minimize your heating, and the soils with more thickness are less dependence on the vegetation. The best thermal performance was observed in soils of 0.10 m compared to shallower depths, but did not vary significantly its thermal behavior with the cultivation of three different species of plants, referring to amounts of coverage achieved in this experiment.
164

Development and Testing of a Second Generation Hand-held Optical Imager

Gonzalez, Jean 22 March 2012 (has links)
Hand-held optical imagers are developed towards clinical breast cancer imaging. Herein, a Gen-2 hand-held optical imager has been developed with unique features: (i) image curved breast tissues with ~86% surface contact, and (ii) perform reflectance and transillumination imaging using the novel forked probe heads. Extensive phantom studies were performed using 1% Liposyn solution (background, ~ 300 ml and 1000 ml volumes) and 0.45 cc India Ink (absorption) targets, under different target:background contrast ratios and target depths. Two-dimensional surface images detected target(s) up to 2.5 cm deep via reflectance imaging, and up to 5 cm deep via transillumination imaging. Preliminary studies on gel-based breast phantoms (~700 ml) detected targets via reflectance and transillumination imaging. Preliminary in-vivo reflectance studies on normal and cancerous breast tissues also detected targets, although with artifacts. In future, the portable Gen-2 imager has potential for clinical breast imaging via reflectance and transillumination approach after extensive in-vivo studies.
165

Obecní restaurace / Municipal restaurant

Dokulil, Petr January 2018 (has links)
Diploma thesis on a topic ‘Municipal restaurant‘ deals with a new building proposal of a restaurant. An object is designed in the central part of a village called Štěměchy. It is a brick detached building in a slightly sloping terrain. The new building is a double-storeyed. The building has a letter ‘L‘ shape in the floor plan. The main entrance is situated from the south-east side. We can enter the restaurant from the wind lobby. The restaurant is connected with a bar and an outdoor terrace. There is a beverage store etc. next to the bar. A sanitary located background and a cleaning room are at the back side. There are accessible bowling lanes from this place. There are two entrances to the building from the north-east side. We can enter the outdoor equipment storage from the first door and the second one to the hallway which is served as for deliveries, an employee´s entrance and for taking the rubbish out from the waste repository of the kitchen. The hallway connects the restaurant to the kitchen which adheres to the rough vegetable preparation, a store with a freezer and some fridges, a dry store, a background for employees, an office, a cleaning room, an oil store, a mixed waste, a cooled waste and a utility room. There is an attic which is accessible from the wind lobby behind the main entrance. We can go to the hallway up the stairs. The hallway connects the area for exercise and an associated store of exercise aids to the roof terrace, the cleaning room and the sanitary facilities. The sanitary facilities is divided to the men´s part and women´s part. It is made by changing rooms, showers and toilets. The wall system is formed by ceramic blocks of Porotherm. There are a timber joist floor and a plank floor in the attic part. There is a system ceiling of Porotherm company where is placed a warm flat roof´s assembly with an extensive greenery . The attic part is roofed by the sloping gable double–layer roof which is made by a timber collar beam´s roof truss.
166

Hlavní budova vlakového nádraží / The main building of the railway station

Woytela, Jindřich January 2018 (has links)
The subject of my thesis is the design the main building of the railway station, which is located in the city of Kuřim, at the level of documentation for construction. The new building is located in the cadastre unit Kuřim. This is a two floors with partial basement building irregular rectangular shape with parking for traveler. The structural system is consists of wooden BSH beam and placed on them wooden CLT panel for walls, floor and flat roofs. Design of the main building of the railway station respects established requirements.
167

Tančírna u rybníka / Gaff by the pond

Vondra, Miloš January 2018 (has links)
The project involves the design and solution of a restaurant with dance floor and accommodation. This includes a new building on land plot 389/1, 389/3, 389/4, 1632/2, 1632/3, 1634/9, located in the town of Čáslav. Access to the building and layout inside the building is barrier-free. The restaurant is designed for a capacity of 120 people to sit. The total bed capacity of the pension is 14 beds. One double room is designed for barrier free use of the accommodation unit. The structural system of the object is masonry, with additional elements of the cast-in-place concrete frame. At the site of the largest span are designed reinforced concrete columns and dimensioned 0.3 x 0.3 m with a maximum centre to centre spacing of 5.31 x 5.775 m. Basement masonry is supposed to be from permanent shuttering. The masonry part of the building at the groundfloors is made from ceramic blocks of type POROTHERM with 300 mm thickness. Internal loadbearing masonry and not loadbearing masonry walls are built from ceramic blocks of POROTHERM with thickness 250, 150, 80 mm, or plasterboard partition with thickness 155 mm. The building is insulated with a contact insulation system. The (exterior) building envelope is designed with a ventilated air gap. The floor structure is supposed to be from reinforced concrete monolithic slab. The building is roofed with a flat roof with a single-layer flat roof with a classical layout. Above the restaurant will be an extensive green roof.
168

Studentský dům / Student House

Lisá, Nikola January 2019 (has links)
The thesis is focused on elaboration of project documentation. The student house will be located in the city of Ostrava. The building has 4 above-ground floors with partial basement .The basement will for the most part serve as a technical facilities. On the first floor there will be rooms - reception, reception, office, bicycle room, café, small shop, gym, copy center, facilities and hygienic room. Residential units are located on 2 to 4 floors. There will be 26 residential units - single and double, total for 54 persons. Each residential cell has its own sanitary facilities and a kitchenette. The building is designed as a masonry system. The load-bearing masonry in the basement is from a lost formwork of 300 mm. external wall and internal supporting masonry of above-ground floors of clay masonry, Therm type, 300 mm. The warm flat roof is extensive, with a fall of 3%.
169

Polyfunkční dům / Mixed-use building

Jenerál, Pavel January 2019 (has links)
The Thesis deals with a proposal for a new mixed-used building in the city of Moravske Budejovice in the cadastral area of Moravske Budejovice. The building is a three-floored house without a cellar. The roof of the house is completely flattened. On the first floor, there are commercial rooms, hairdresser´s and a bookshop. Apartments are on the second and third floor. The construction will be built of clay blocks which are 300 mm wide. The insulation of the building is formed by thermal insulation composite system. The ceiling is created by reinforced concrete slabs 250 mm wide. Parts of the documentation are water-supply, electricity, pipeline and waste water pipe. The description of pavement and driveway is included. The Thesis is written as a project to build the construction.
170

Kraví hora - rodinné stříbro VUT / Kraví hora - BUT Family silver

Prosseková, Jarmila Unknown Date (has links)
The focus of this thesis is an architectural study of the Kraví Hora area in Brno in a 1:200 scale. The area is significant in both size and location, but has been underutilized up to this point. The objective of the thesis is to discover a solution acceptable for the city of Brno as well as BUT, whose intentions with the area differ significantly. The area has been designed to have recreational spaces of greenery. Traffic has been either largely reduced, or eliminated entirely. A wide variety of sports, eductational programs and recreational activities has been made available for visitors of all ages. The objective of the planned area is to inspire and positively motivate the study of technology and interest in science via its functional design. Exhibition areas, lecture halls, rentable workspaces for graduates, a recruitment center and general storage spaces has been designed in the area. The design of the buildings is based around the incline of the plot – they have a maximum of one extra floor over the level of the surrounding terrain. The green roof and the vertical outer layer of laminated timber is designed to provide a natural character to the structures. The predominantly horizontal area is granted an element of verticality in the form of a lookout tower.

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