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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.
291

Masokombinát / Meatpacking plant

Majtán, Marián January 2017 (has links)
The diploma thesis is focused on project documentation of Meat packing plant. Along with meat processing the documentation solve question of accomodation for employees. Building consists of two main sections: The processing – it is structured under requierements of meat packing industry. Second one is residential part set in 2nd, 3rd and 4th floor. Main inspiration for design are meat packing plants in Scandinavian countries, where is often need to provide accomodation to employess because of disadvantageous geographic locality. Building is built of Heluz building system, perimeter walls consists of insulation filled blocks. Building is without basement and it is based on footings of plaint. The roof is flat, partially designed as extensive green roof. Isover system is used to thermal insulation. A part of object is also asphalted plain for transport goods to and from the meat packing plant.
292

Polyfunkční dům / Multifunctional building

Matulík, Jakub January 2017 (has links)
The master’s thesis deals with design documentation of a multifunctional building in Vyskov. The property consists of eight apartments, shops and offices. It is a detached, three-storey building without a basement. Parking space is solved by parking in front of the building. The shape in plan consists of three rectangles with a flat roof. The house is fitted to almost flat terrain. The main entrances to the building are situated to the north, west, northwest. The building is designed from the structural system POROTHERM.
293

Polyfunkční dům v řadové zástavbě / Multifunctional house in terraced houses

Šaár, Martin January 2017 (has links)
The diploma thesis deals with the design documentation of new Multifunctional house in terraced houses on the level of documentation for building permit. The living area is designed for housing eight people. Part with shops and with offices are designed for seventy three people. The building will be located in the Zlín Region, District of Uherské Hradiště, in the city of Uherský Brod. The Cadastral area is Uherský Brod - the town. The bulding has four aboveground floors and he hadn't cellar. The building is designed like a brick structure with column and girder. Vertical structures aboveground parts are made of bricks Porotherm and column and girder are from reinforced concrete C16/20 and shoring B500B. Platform of a multifunctional house in terraced houses is of rectangular shape with dimensions of 25,20 x 16,30 m. The main entrance to the building is located on the south side. Part with shops in first floor have four shops. In the second floor are four offices. Whole building are roofed helped three diferent roof construction. Above living part is gabled roof and above technical room and staircase is compact flat roof and the rest of building is vegetation roof with terrace.
294

Polyfunkční dům / Multifunctional Building

Teplý, Jan January 2017 (has links)
The dissertation contains the project and working out of the designing documentation for execution of a multifunctional building. The project deals with a new multifunctional building in the marginal part of the Olomouc city. The object is a brick building with no cellar and four above-ground floors. The ground plan of the building is regular and mainly rectangular. There are balconies at the corner and in the middle of the eastern part of building in above-ground floors. The last floor is partially receding and there are two terraces here. There is the flat roof construction. The horizontal and vertical supporting and non-supporting constructions are suggested from the Heluz´s brick system. There are three places of business on the ground floor and ten flats on the above-ground floors. The building site has a plane terrain.
295

Contrôle de la fonctionnalisation par réduction des sels de diazonium via le piégeage radicalaire / Control of the grafting by diazonium salt reduction using radical scavenger

Menanteau, Thibaud 19 September 2016 (has links)
La fonctionnalisation de surface par réduction de précurseurs diazoniums est une puissante méthode de fonctionnalisation de surface. Cependant, bien que cette approche permette l’obtention de matériaux robustes, elle reste encore mal maîtrisée et conduit systématiquement à l’élaboration de films organiques épais, non reproductibles, et structurellement désorganisés. Dans ce contexte, nous avons développé une méthodologie permettant le contrôle du greffage dans le but de réaliser des matériaux organisés et reproductibles. Basée sur l’utilisation de piégeur de radicaux, cette méthode a permis l’obtention d’une monocouche sur un substrat carboné. La stratégie de contrôle a ensuite été exploitée pour bloquer sélectivement le mécanisme radicalaire et évaluer le rôle des mécanismes non-radicalaires dans le processus de greffage. Cette étude a permis une meilleure caractérisation du processus de greffage et mis en lumière l’impact du substituant du précurseur diazonium sur le processus de croissance du film organique. L’exploitation de ces connaissances a été mise à profit via la réalisation d’une plateforme monocouche multifonctionnelle. L’étude des relations structures/propriété a révélé des performances accrues en matière de transfert électronique et d’électro catalyse. Pour finir, la transposition de la méthode de contrôle à un greffage de type spontané a fourni un résultat similaire à celui observé pour le greffage électro-induit. L’approche a été validée par l’optimisation des performances d’un super condensateur réalisé à base de matériaux carbonés dispersés. / The surface functionalization by diazonium salt reduction is a powerful grafting method. However, despite that this approach allows the preparation of robust materials, it leads to thick and unorganized organic films. In this context, we have developped a method allowing the grafting control in order to obtain films having controlled thickness. Based on the use of radical scavengers, this method gives access to monolayer formations on carbon substrates. The control strategy was then exploited to selectively block the radical grafting mechanism and allows to assess the role of non-radical mechanisms in the process. This study provided a better understanding of the layer growth, highlighting the impact of precursor substituent.This knowledge has been used to elaborate a multifunctional platform monolayer. The establishment of sutructure/properties relathionships revealed better performances for electronic transfert and electrocatalysis. Finally, the control method was transposed to the spontaneous grafting and gives similar results than those obtained for the electrochemical one. This approach was validated by the performance optimization of supercapacitor made of carbon powder.
296

Cultivating the city - a multifunctional landscape along the Walker Spruit, Pretoria

Rossi, Dominique Gina 07 December 2012 (has links)
The purpose of this dissertation was to explore how a landscape architect may help to address environmental decay and the threat of food scarcity that are the results of rapid urban growth. For this urban renewal scheme, it is proposed that the underutilized open spaces within the city are reclaimed and interconnected in order to maximize their potential, forming a continuous landscape network. It is believed that this landscape network needs to function beyond mere beautification in order to be successful and productive. A multifunctional strategy is thus brought forward, as emphasis is placed upon providing for food security and realizing the city’s wasted resources. Along with related economic and ecological advantages, ways in which open space may be more sustainably managed are explored. Acknowledging the sheer lack of municipal funds, community involvement is believed to be the catalyst of this vision. Surrounding neighbourhoods are hence proposed to be the maintainers of their surrounding open spaces, decreasing the monetary pressures on the authorities. Emphasis is placed on ways in which communities may be incorporated through designing for flexibility, pride of ownership and sense of belonging. A new identity that ties in with the original genius of place is ultimately promoted through this meaningful utility parkland. An abandoned stretch of land along the Walker Spruit between Pretoria’s Sunnyside East and Clydesdale suburbs served as a model for testing the hypothesis of a spatially continuous, linear and productive community park. / Dissertation ML(Prof)--University of Pretoria, 2012. / Architecture / Unrestricted
297

Conversor multifuncional conectado à rede elétrica para compensação de oscilações de potência instantânea /

Olímpio Filho, José de Arimatéia January 2019 (has links)
Orientador: Helmo Kelis Morales Paredes / Resumo: Esta dissertação de mestrado propõe o desenvolvimento e a implementação de uma estratégia de compensação para conversores eletrônicos de potência (CEP) multifuncionais conectados à rede elétrica. A geração dos sinais de referência de corrente para o conversor multifuncional é obtida através das grandezas conservativas da CPT, do inglês Conservative Power Theory. O CEP proposto neste trabalho desempenha o papel de um conversor interface de rede no modo conectado, tendo como finalidade a mitigação de oscilações de potência instantânea bem como injeção de potência ativa na rede elétrica, caracterizando assim o seu aspecto multifuncional. São realizados estudos teóricos e simulações computacionais com o intuito de validar a estratégia proposta. Para tanto, foram identificadas as parcelas indesejadas de corrente que permitam a compensação das componentes oscilatórias da potência instantânea e da energia reativa instantânea da CPT. O CEP é controlado em modo corrente, através da estratégia de modulação PWM com duas malhas de controle. A estratégia de compensação e o sistema de controle serão avaliados e testados via simulação para diferentes configurações de cargas, incluindo uma carga não-linear desbalanceada operando em condições onde as distorções e desequilíbrios de tensão sejam consideráveis. Por fim, resultados experimentais obtidos com um protótipo em escala laboratorial são utilizados para validar a estratégia de compensação proposta / Abstract: This master’s thesis proposes the development and implementation of a compensation strategy for the three-phase multifunctional grid-tied inverter. The reference signal generation method for grid-tied is based on the Conservative Power Theory (CPT). In this work, the multifunctional inverter plays the role of the Utility Interface (UI) which perform several functions: in grid-connected operation, it injects active power into the grid and compensates the instantaneous power oscillation and the instantaneous reactive energy oscillation. The goal is to execute theoretical studies and computational simulations to validate the proposed strategy. For this purpose, firstly are identifies the unwanted currents which allow the compensation of the oscillatory terms of instantaneous power and reactive energy. The inverter is controlled in current mode through PWM modulation strategy with two control loops. In addition, the proposed compensation strategy and control system is evaluated and tested for different load configurations, such as linear and nonlinear loads (balanced and unbalanced) operating under different voltage conditions (distorted and unbalanced). Finally, experimental results are presented to validate the effectiveness and performance of the proposed compensation strategy. / Mestre
298

An integrative approach to assess urban riparian greenways potential: The case of Mapocho River in Santiago de Chile

Vásquez, Alexis 27 June 2016 (has links)
Santiago is the 7th largest major city of Latin America with almost 8 million inhabitants and is situated in a fairly closed watershed, surrounded on the eastern side by the high Andean mountain chain with altitudes of 5,000 m. From the Andean mountains, the Mapocho River and a set of large and small streams transport -often torrentially- water and sediment. In thirty years, Santiago has increased its size two fold, replacing previous agricultural lands, native forests and shrubs with urban land uses, and occupying rivers beds and streams. These land use and cover changes have had dramatic environmental consequences. The mentioned urban dynamic has produced a city in constant collision with the natural system. This structural disarticulation produces many environmental problems such as an increase in city’s surface and air temperatures, an accelerated disappearance of vegetation, a major interruption in wind, sediment and water flows, and finally, increasing people’s exposure to environmental hazards. Since streams, canals and rivers are structural components of Santiago’s landscape, they can function as key links between the urban-social and natural system and provide multiple ecosystem services, helping to reduce environmental problems and ensure long-term urban sustainability. Traditionally, the analysis of river and streamsides has been focused on rural and natural landscapes as well as on environmental protection and nature conservation. Nowadays, there is an increasing interest and necessity to understand the environmental status, functions and possibilities of riparian zones in urban environments in order to delineate and plan greenways, which provide social and ecological benefits. Green infrastructure such as urban greenways is a key component of sustainable cities. Few studies have been conducted to evaluate the socio-ecological status of urban riparian zones and even fewer to assess these areas in terms of their potential as multifunctional greenways. New efforts should be conducted to develop analytical application-oriented frameworks in the green infrastructure field. This research elaborates and proposes a transferable conceptual-methodological framework for evaluating the potential for multifunctional riparian greenway development. An analytical application-oriented framework to assess the potential for multifunctional green infrastructure development is proposed by articulating and improving three analyses hitherto used separately: multicriteria, least cost path and opportunities-challenges. The Mapocho River was selected for the application and testing of the proposed conceptual-methodological framework to contribute to multifunctional green infrastructure planning in Santiago as a city representative of the structure and processes of megacities in Latin America. First, the main ecological and social characteristics of the Mapocho’s riparian zone are analyzed, making a synthesis of the socio-ecological status. Second, the suitability to provide multiple ecosystem services of the riparian zone is spatially explicitly modelled, first separately, as mono-functional suitability, and then, integrated into a multifunctional suitability evaluation. Third, the opportunities and challenges perceived by government actors are identified and analyzed as well as those derived from an institutional and regulatory analysis. Finally, the assessment phase concludes with a discussion on the main potential for the development of a greenway, resulting from the synthesis and integration of the most relevant findings of the suitability and opportunities analysis The socio-ecological status of the riparian zones is characterized by being highly altered in ecological terms, diverse in social terms, and highly used by the metropolitan transport infrastructure with a concentration of green areas in a few municipalities. This means that the riparian zone provides limited physical support for important social and ecological functions characteristic of these zones in urban environments: habitat, aesthetic, cooling, transport route and flood mitigation. The results reveal a significant east-west gradient in the socio-ecological status of riparian zone, which gradually decreases from east to west. The riparian zone of the Mapocho River in Santiago has good suitability as a wind corridor, providing a cooling effect and to mitigate flood hazards. The main challenges for the development of a multifunctional urban greenway in the Mapocho River corresponds to low levels of inter-jurisdictional and inter-sectoral coordination and cooperation, maintenance costs and the existence of urban highways in the zone. On the contrary, the main opportunities are the existence of important sectors of vacant land, increased political and social importance of urban green areas and the existence of a set of consolidated riparian parks. In synthesis, the assessment developed in the Mapocho River identifies the most important aspects to be considered and the greatest potentialities to capitalize in planning a multifunctional greenway along the Mapocho River. This is key when thinking about a possible master plan for the Mapocho River that returns the river to the city and values it as an axis for urban integration. The development of a multifunctional greenway in Santiago can considerably contribute to the social and ecological connectivity and thereby mitigate the socio-ecological segregation and disconnection characteristic of cities in the region. It may also contribute significantly to reconcile urban growth with ecological health and people’s quality of life, maintaining functions and key ecosystem services and mitigating the negative effects of urbanization.
299

Bio-inspired Multifunctional Coatings and Composite Interphases

Deng, Yinhu 19 October 2016 (has links)
Graphene nanoplatelets have been introduced into the interphase between electrically insulating glass fibre and polymer matrix to functionalize the traditional composite. Owing to the distribution of network structure of GNPs, the interphase can transfer the signals about various internal change of material. Consequently, due to the novel bio-inspired overlapping structure, our GNPs-glass fibre shows a unique opportunity as a micro-scale multifunctional sensor. The following conclusions can be drawn from present research: • We prepared GNPs solution via a scalable and highly effective liquid-phase exfoliation method. This method produces high-quality, unoxidized graphene flakes from flake graphite. We control the thickness and size of GNPs by varying the centrifugation rate. • A simple fibre oriented capillary flow which can suppress ‘coffee ring’ effect to deposit GNPs onto the curved glass fibre surface. The GNPs form continuous fish scales like overlapping structure. • The electrical conductivity of our GNPs-glass fibre shows semiconductive property. The electrical resistance value scattering and the advancing contact angle value scattering indicate a uniform deposit structure. The uniform overlapping structure is a key factor for higher electrical conductivity compared with our previous work with CNTs. • The contact angles of our GNPs-glass fibre with water indicate that the GNPs are almost unoxidized, so the inert GNPs coating decreases the interfacial shears strength. • A micro scale GNPs-glass fibre sensor for gas sensing is achieved by deposit GNPs onto glass fibre surface. This sensor can be used to detect solvents vapours, such as water, ethanol and acetone. All these vapours work as electron acceptor when reacting with GNPs. The acetone shows the highest sensitivity (45000%) compared with water and ethanol. • The doping-dedoping of GNPs-glass fibres during adsorption-desorption cycles of acetone result in the efficient “break-junction” (GNPs lost electron carrier concentration) mechanism, which provides the possibility to fabricate the electrochemical “switch” in a simple and unique way. • The resistance of our GNPs-glass fibre shows exponential relationship with RH. This is attributed to two points. Firstly, the water vapours show similar exponential adsorption on carbon surface; secondly, the bandgap of GNPs increases with the increase of adsorbed water vapour concentration. • Due to the weak van der Waals interaction when water molecules are adsorbed on GNPs surface, our GNPs-glass fibre shows extreme fast response and recovery time with RH. It is potential for our GNPs-glass fibre being used to monitor the breath frequency. • Utilizing the negative temperature coefficient of GNPs, our GNPs-glass fibre can be used as temperature sensor with a sensing region of -150 to 30 °C. • Through the observed abnormal resistance change at a temperature of about – 18 °C, we discovered a phase change of the trance confined water in graphene layers. Based on the resistance change, we can study the interaction of water and carbon nanoparticles. • The bio-inspired novel overlapped multilayer structure of GNPs coating shows structural colours. Even more, our GNPs-glass fibre can be used to monitor the loading force in the interphase when it is embedded into epoxy resin. • Our GNPs-glass fibre shows an excellent piezoresistive property, the single GNPs-glass fibre shows a larger gauge factor than the commercial strains sensor. • The semiconductive interphase was formed when the GNPs-glass fibre was embedded in polymer matrix. This semiconductive interphase is very sensitive to the deformation of material, therefore, an in-situ strain sensor was manufactured to real-time monitor the microcracks in a composite instead of external sensors. The area of resistance ‘jump’ increase can be seen as the feature area for damage’s early warning. • Monitoring the resistance variation of the single fibre composite was conducted under cyclic loading with progressively increasing the strain peaks in order to further investigate the response of in-situ sensor to the interphase damage process. The deviation of resistance/strain when the stress is larger than 2 % highlights the accumulation of damage, which gives insight into the mechanism of resistance change.
300

Development and Investigation of High-Performance Fire Retardant Polypropylene Nanocomposites via High Energy Electrons

Xiao, Dan 04 October 2017 (has links)
Polypropylene (PP) has excellent mechanical and chemical properties. Thus, it is used in a wide range of applications. However, like for most polymers, the high flammability of PP limits its application in various fields requiring specific flame-retardant standards. Some of halogenated flame retardants are restricted by European Community directives ROHs, WEEE and REACH. Now metallic hydroxides flame retardants are widely used in industry, but the high loading (about 60 wt %) seriously destroys the mechanical properties of polymeric materials. To improve the performance of flame retardant polymers, an environment-friendly electron beam (EB) technology has been successfully used in modifying flame retardant and polymer matrix. In this work, high efficient functional intumescent flame retardants and functional surfactant are designed and prepared for EB technology. In-depth studies the thermal stability, fire behavior and mechanical properties of these flame retardant PP composites have been studied. The possible graft-linking and cross-linking mechanisms of such EB modified composites can be well established. Specially, it is shown that the novel surfactant has better thermal stability in comparison to traditionally used modifiers. Another part of this work deals with the exploration of novel allylamine polyphosphate (AAPP) as flame retardant crosslinker for PP by electron beam (EB) treatment. Multifunctional AAPP showed unique efficient intumescent flame retardant properties. The limiting oxygen index (LOI) value and the effective melt drop resistance in UL-94 test of multifunctional flame retardant PP composites is greatly enhanced. In the cone calorimeter test, a reduction of peak heat release rate, total heat release and smoke production is achieved. Moreover, EB treatment increased the thermal stability of these designed flame retardant PP composites. Furthermore, AAPP provided an excellent quality of char residue in the combustion stage due to P−N−C and P−O−C structure. In addition, synergistic mechanism of AAPP with montmorillonite (MMT) was explored. Finally, different EB parameters have been used to modify fire retardant polymer nanocomposites. The effects of EB treatment on thermal stability, fire behavior and mechanical properties of fire retardant PP nanocomposites have been discussed. The heat release, the production of toxic gases and the mass loss of EB modified fire retardant PP nanocomposites are delayed in accordance to the result of cone calorimeter test. Based on these results high performance fire retardant polymer nanocomposites can be developed for industrial applications such as insulated material of wire, cable, etc.

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