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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.
201

Metódo de obtenção de dados de impactos ambientais, durante o processo de desenvolvimento do projeto, através do uso de ferrramenta BIM / Method of obtaining environmental impact data, during the design development process through use of BIM tool

Marcos, Micheline Helen Cot 24 April 2015 (has links)
O setor da construção civil é responsável por uma parcela significativa do consumo de recursos naturais, incluindo energia, emissão de CO2, água e materiais de construção. O tripé ambiente, economia e sociedade deve ser considerado de uma maneira integrada na indústria da construção civil, para atender as expectativas da sociedade e ao mesmo tempo reduzir impactos ambientais (AGOPYAN, JOHN, 2011). Novas tecnologias construtivas aliadas a novas tecnologias projetuais podem contribuir para a melhoria do ambiente construído na área de eficiência energética, desempenho térmico e impactos ambientais (FREIRE, M.; AMORIM, A., 2011). Essa pesquisa tem como objetivo principal: desenvolver um método de obtenção de dados de impactos ambientais, durante o processo de desenvolvimento do projeto, através do uso de uma ferramenta de Modelagem da Informação da Construção (\"Building Information Modeling\" - BIM), para auxiliar na tomada de decisões quanto ao sistema construtivo que proporcione menor impacto ambiental. Para essa pesquisa, foram analisados o CO2 incorporado e a energia incorporada nos materiais de construção. Para validação da pesquisa, o método adotado foi o estudo de caso onde foram analisados dois sistemas construtivos: aço leve (\"steel frame\"\') e alvenaria, aplicados em um mesmo condomínio com vinte habitações unifamiliares, que se encontram na fase de projeto. A partir da revisão da literatura foram extraídos os dados de energia e CO2 incorporado dos principais materiais de construção utilizados nos dois sistemas construtivos. Em seguida esses dados foram inseridos em uma ferramenta BIM. Primeiramente foram analisados e obtidos os resultados das vinte casas em alvenaria, em seguida realizou-se o mesmo processo para uma única casa e, para finalizar, de uma parede. Esse estudo se repete para o sistema em aço leve (\"steel frame\"). Como resultado obtém-se dados de impactos ambientais, auxiliando o profissional na escolha dos materiais de construção e sistemas construtivos com menor impacto ambiental. / The construction sector accounts for a significant portion of natural resources consumption, including energy, CO2 emissions, water and building materials. The environment, economy and society should be considered in an integrated manner in the construction industry to meet society\'s expectations while reducing environmental impacts (AGOPYAN; JOHN, 2011). New construction technologies combined with new projective technologies can contribute to the improvement of the built environment in the area of energy efficiency, thermal performance and environmental impacts (FREIRE, M.; AMORIM, A., 2011). This research aims: to develop a method of obtaining informations of environmental impacts during the project development process, through the use of a modeling tool of Information Construction (\"Building Information Modeling\" - BIM), to assist in making decisions about building system that provides lower environmental impact. For this research, the embedded CO2 and energy in building materials were analyzed. For validation of the research, the method adopted was the case study which analyzed two building systems: steel frame and masonry, applied in the same condominium with twenty houses, which are in the design phase. From the literature review were extracted energy and CO2 informations built the main building materials used in both building systems. Then these data were entered into a BIM tool. First were analyzed and the results obtained from twenty houses masonry then carried out the same process for a single house, and finally, a wall. This study is repeated for the steel frame system. As a result is obtained data of environmental impacts, assisting the professional in the choice of building materials and construction systems with lower environmental impact.
202

Investigating the structural frame decision making process

Haroglu, Hasan January 2010 (has links)
Structural frames are widely used in sectors such as residential, education, commercial, health, retail, leisure etc. and the selection of a structural frame appropriate to a building s function and client needs is a key decision with significant short- and long-term implications. There is a wide choice of structural frame materials for building projects, i.e concrete, steel, timber, or masonry. Although many options are available, these tend to be based on structural steel or reinforced concrete for the simplest buildings. The nature of concrete frame buildings has developed significantly with the emergence of new technologies and innovations particularly in formwork, concrete as a material, and reinforcement developments. As a result, concrete frame construction has become a faster, more sustainable, and safer form of construction. However, competition from other framing materials such as steel have proved challenging. This research was initiated in response to this challenge and represents one organisation s attempt to deliver improvements in order to promote concrete in the UK structural frames market. The organisation is strongly focused on the continued development of concrete through design inspiration and construction efficiency, research strategy, education and training, new product and process innovation and the achievement of best performance of concrete in practice. The research programme was established to address issues that are considered by decision makers when choosing the optimum frame solution for a building project, and to identify how such decisions are made in practice. Both quantitative and qualitative research methods have been adopted during the EngD research including a literature review, industry questionnaire survey and case study. From an initial set of interviews, ten key issues were identified at the early stage of the research as being the most important affecting the structural frame selection for a building project. The structural engineer was found, unsurprisingly, to be the most influential decision-maker in the choice of frame at each stage of design process from a subsequent survey of cost consultants, project managers and clients. The survey also revealed that Design-Build is the preferred procurement route amongst developers of building projects, ranging from complex, high quality projects to simple buildings which suggested that most contractors must be getting involved earlier in the design process and thus could be influencing major decisions, such as the selection of a structural frame. Four case study project teams were examined, from which it was clear that contractors could be influential in the frame selection process if they had the willingness to build in a particular frame type (provided that the frame type selected meets the client s requirements). Key findings on the choice of frame in a Design-Build project and the various actions taken by the contractor were highlighted by the research, including the important role played in the decision-making process by more informed clients, who are much more likely to be influential in deciding on the frame type. Further work could be carried out to assess the specific benefits of early contractor involvement, the factors that affect the extent to which contractors get involved with structural frame decision making and the risk relationship between client and contractor. The findings of this work have been presented in five peer-reviewed papers.
203

Current sculpture and its spaces; a focus on Great-Britain. From conception to reception, a study of the sculptural frame

Sinan, Tarquin 18 January 2019 (has links) (PDF)
The present thesis examines the notion of “sculptural frame” through a meticulous analysis of the spatial practices observable in British Sculpture from the 20th and 21st centuries. The sculptural medium having been left out of the theoretical debate surrounding the frame’s artistic definition and application, this study’s aim is to make up for this lacuna by focusing on the interdependent relationship between three essential sculptural elements: the body (of the artist and of the beholder), the object and, of course, space. Beginning with Henry Moore and closing with a side-by-side analysis of Rachel Whiteread and Antony Gormley, this research puts forth two fundamental paradigms developed in the first half of the past century – Landscape and Architecture – which articulate much of sculpture’s spatial evolution on the British Isles. Moore’s generation interpreted Landscape as an ideological frame which served both as the origin and the destination of sculpture. Richard Long’s conceptual generation gave this frame a sense of spatial self-sufficiency by dematerializing art, rendering the frame boundless. Anthony Caro, by adopting an architectonic vernacular, progressively welcomed the beholder’s body into inhabitable frame-like sculptures -- a spatial dialogue continued yet re-envisaged by Gormley and Whiteread, who respectively stimulate and negate the sentient spectator. These paradigmatic evolutions reveal a shift in prism in the ’70s, which goes hand in hand with an increasingly internalized spatial trajectory as sculptors transition from a material focus to a corporal one. Based on these spatial assessments, the present thesis challenges the current understanding of the “dividing frame”, proving it to be inadequate, and proposes – using the studied corpuses as argumentative examples – a novel definition of the sculptural frame as an encompassing one. / Doctorat en Histoire, art et archéologie / info:eu-repo/semantics/nonPublished
204

Análise teórica e experimental de vigas mistas de aço e concreto e laje com vigotas pré-moldadas e lajotas cerâmicas em um pavimento tipo / Theorical and experimental analysis of composite steel and concrete beams and slabs made by precast elements with lattice and bricks on a frame

Higaki, Bruno Eizo 11 December 2009 (has links)
As vigas mistas de aço e concreto são elementos estruturais que resultam da associação de um perfil de aço laminado, formado a frio ou soldado, e de uma laje de concreto podendo esta ser moldada in loco, pré-fabricada ou com forma de aço incorporada. A construção de vigas mistas com laje de vigotas pré-moldadas de concreto não é prevista pela norma brasileira de dimensionamento de elementos de aço NBR 8800:2008 e poucos estudos foram realizados até o momento. Geralmente, os estudos realizados sobre vigas mistas são feitos em modelos compostos por perfil de aço e uma faixa de laje denominada largura efetiva. Neste trabalho foi desenvolvido um estudo teórico e experimental de vigas mistas fazendo parte de um pavimento tipo. O objetivo principal foi o estudo do comportamento das vigas mistas pertencentes a um pavimento tipo quando submetidas a diferentes tipos de carregamentos, distribuídos e concentrados, verificação da formação de fissuras na laje e a importância de considerar uma faixa de laje maciça na região da largura efetiva sobre as vigas. A análise numérica foi realizada utilizando o pacote comercial ANSYS e por meio das expressões de cálculo fornecidas pela norma brasileira de aço e adaptações para consideração da pré-laje de concreto. Os resultados mostraram um bom desempenho das vigas mistas comparadas com a resistência de cálculo de acordo com as expressões fornecidas pela norma para vigas mistas com pré-laje de concreto e a importância da execução de uma faixa maciça na região da largura efetiva. / The composite steel and concrete beams are structural elements witch results of association by a hot rolled, cold formed or welded steel beam and concrete slab which can be made in site, precast or with steel deck. The design of composite beams made with slab made with precast type lattice joist isn\'t anticipated by the brazilian code and a few studies has been made up to now. Usually, the studies about composite beams are made with steel beam and a concrete\'s zone called a slab\'s effective width. In this work a teorical and experimetal studies were presented with a frame\'s composite beams. The aim of this work was investigate the behaviour when differents loads, distributed and concentrated, were apllied, find out if cracks appeared and the importance of design a solid slab on the effective width\'s regions. The theorical analysis made using the code ANSYS v.10.0 and with expressions of brazilian code for composite beams with precast slabs. The results have shown a good agreement with code\'s analitical models and teh importance of design a solid slab on the effective width\'s regions.
205

Metódo de obtenção de dados de impactos ambientais, durante o processo de desenvolvimento do projeto, através do uso de ferrramenta BIM / Method of obtaining environmental impact data, during the design development process through use of BIM tool

Micheline Helen Cot Marcos 24 April 2015 (has links)
O setor da construção civil é responsável por uma parcela significativa do consumo de recursos naturais, incluindo energia, emissão de CO2, água e materiais de construção. O tripé ambiente, economia e sociedade deve ser considerado de uma maneira integrada na indústria da construção civil, para atender as expectativas da sociedade e ao mesmo tempo reduzir impactos ambientais (AGOPYAN, JOHN, 2011). Novas tecnologias construtivas aliadas a novas tecnologias projetuais podem contribuir para a melhoria do ambiente construído na área de eficiência energética, desempenho térmico e impactos ambientais (FREIRE, M.; AMORIM, A., 2011). Essa pesquisa tem como objetivo principal: desenvolver um método de obtenção de dados de impactos ambientais, durante o processo de desenvolvimento do projeto, através do uso de uma ferramenta de Modelagem da Informação da Construção (\"Building Information Modeling\" - BIM), para auxiliar na tomada de decisões quanto ao sistema construtivo que proporcione menor impacto ambiental. Para essa pesquisa, foram analisados o CO2 incorporado e a energia incorporada nos materiais de construção. Para validação da pesquisa, o método adotado foi o estudo de caso onde foram analisados dois sistemas construtivos: aço leve (\"steel frame\"\') e alvenaria, aplicados em um mesmo condomínio com vinte habitações unifamiliares, que se encontram na fase de projeto. A partir da revisão da literatura foram extraídos os dados de energia e CO2 incorporado dos principais materiais de construção utilizados nos dois sistemas construtivos. Em seguida esses dados foram inseridos em uma ferramenta BIM. Primeiramente foram analisados e obtidos os resultados das vinte casas em alvenaria, em seguida realizou-se o mesmo processo para uma única casa e, para finalizar, de uma parede. Esse estudo se repete para o sistema em aço leve (\"steel frame\"). Como resultado obtém-se dados de impactos ambientais, auxiliando o profissional na escolha dos materiais de construção e sistemas construtivos com menor impacto ambiental. / The construction sector accounts for a significant portion of natural resources consumption, including energy, CO2 emissions, water and building materials. The environment, economy and society should be considered in an integrated manner in the construction industry to meet society\'s expectations while reducing environmental impacts (AGOPYAN; JOHN, 2011). New construction technologies combined with new projective technologies can contribute to the improvement of the built environment in the area of energy efficiency, thermal performance and environmental impacts (FREIRE, M.; AMORIM, A., 2011). This research aims: to develop a method of obtaining informations of environmental impacts during the project development process, through the use of a modeling tool of Information Construction (\"Building Information Modeling\" - BIM), to assist in making decisions about building system that provides lower environmental impact. For this research, the embedded CO2 and energy in building materials were analyzed. For validation of the research, the method adopted was the case study which analyzed two building systems: steel frame and masonry, applied in the same condominium with twenty houses, which are in the design phase. From the literature review were extracted energy and CO2 informations built the main building materials used in both building systems. Then these data were entered into a BIM tool. First were analyzed and the results obtained from twenty houses masonry then carried out the same process for a single house, and finally, a wall. This study is repeated for the steel frame system. As a result is obtained data of environmental impacts, assisting the professional in the choice of building materials and construction systems with lower environmental impact.
206

Design and Scale-Up of Production Scale Stirred Tank Fermentors

Davis, Ryan Z. 01 May 2010 (has links)
In the bio/pharmaceutical industry, fermentation is extremely important in pharmaceutical development, and in microbial research. However, new fermentor designs are needed to improve production and reduce costs of complex systems such as cultivation of mammalian cells and genetically engineered micro-organisms. Traditionally, stirred tank design is driven by the oxygen transfer capability needed to achieve cell growth. However, design methodologies available for stirred tank fermentors are insufficient and many times contain errors. The aim of this research is to improve the design of production scale stirred tank fermentors through the development of dimensionless correlations and by providing information on aspects of fermentor tanks that can aid in oxygen mass transfer. This was accomplished through four key areas. Empirical studies were used to quantify the mass transfer capabilities of several different reactors. Computational fluid dynamics (CFD) was used to assess the impact of certain baffle and impeller geometries. Correction schemes were developed and applied to the experimental data. Dimensionless correlations were created from corrected experimental data to act as a guide for future production scale fermentor design. The methods for correcting experimental data developed in this research have proven to be accurate and useful. Furthermore, the correlations found from the corrected experimental data in this study are of great benefit in the design of production scale stirred tank fermentors. However, when designing a stirred tank fermentor of a different size, further experimentation should be performed to refine the correlations presented.
207

Människans intresse och förmåga att skapa världar : En kvalitativ undersökning om den improviserade scenens uppbyggnad och dragningskraft

Hardestam, Hjalmar January 2019 (has links)
Improvisationsteater är en teaterform där scenerna byggs upp gemensamt och skapas i samma ögonblick som den återges. Uppsatsens syfte har varit att undersöka varför människor vill improvisera samt vilka faktorer som utgör ett lyckat samspel och därmed kan skapa en scen. Samspelet i improvisationsteater ställs även i kontrast mot människans samspel i vardagen. Syftet besvaras med hjälp av två olika frågeställningar: dels varför informanterna vill hålla på med improvisationsteater och dels hur de gör för att tillsammans skapa, samspela och förstå varandra i ett sammanhang som hittas på och återges i stunden. Resultaten analyseras och diskuteras utifrån teorier om symboliskt universum och frame vilka är sprungna ur kunskapssociologin och den symboliska interaktionismen. För att möta syftet valde jag att göra en kvalitativ undersökning med explorativ ansats. Jag intervjuade fyra informanter som alla har en gedigen erfarenhet av att improvisera. På grund av det begränsade urvalet valdes dessa informanter med hjälp ett bekvämlighetsurval, något som var möjligt tack vare två nyckelinformanter. Utifrån de kvalitativa intervjuerna framkom temat ’Friheten att tillsammans skapa en ny värld’ som källa för intresset av improvisationsteater. Som svar på ett lyckat samspel i scenen genererades två teman; ’Den teoretiska verktygslådan’ och ’Improvisatörens nödvändiga förmågor’. Uppsatsens huvudsakliga slutsats är att improvisationsteater utgör en unik ’parantes’ kring verkligheten. Det är ett sammanhang där människor medvetet kan bete sig på sätt som inte hade varit möjligt i vardagen. På så sätt får de tillgång till unika upplevelser och erfarenheter. Dessa begränsas dock till förmån av inramningen och samspelet. Samspelet möjliggörs genom två ’grundpelare’. Den ena utgörs av improvisationsteaterns struktur som är utformad för att snabbt inrama situationen. Den andra utgörs av några centrala förmågor vars syfte är att möjliggöra en ömsesidig intrycksstyrning och teammaskopi. Genom improvisationsteater ges individen således möjlighet att fritt och ohämmat undersöka och öva på det sociala samspelet.
208

The Role of EF-G in Translational Reading Frame Maintenance on the Ribosome

Peng, Bee-Zen 14 September 2018 (has links)
No description available.
209

A computer model for Chinese traditional timber structure: the Foguang Temple.

Cao, Dapeng January 2005 (has links)
This thesis presents a study of an ancient Chinese timber structure- the main hall of the Foguang temple built in China in the Tang Dynasty (857), which is regarded as one of the most important temples in that period. The research represents a detailed digital model of the structural timber components and their connectivity. The research questions are: - Firstly, how to identify and represent the structural components, and the ways they are assembled. This is not covered in the few previous studies of the temple, which just offered brief introductions and general descriptions of the construction of the timber structure. - Secondly, how to create a digital model for such a structure where there is insufficient or incompatible information. These are common issues that arise in the simulation and representation of historic architecture. The outcome of the research is the presentation of a digital model that is much more detailed than previously existing representations. During the process, two concepts were developed and adopted: - Firstly, the concept of "building an ideal model". Rather than seeking the representation of the timber structure as built, the notion outlined in this thesis is to create an ideal digital model according to the vocabulary of structural components and the predefined spatial relations of their assembly connectivity. - Secondly, the concept of "simplest adaptation". When choosing from a number of reasonable hypotheses about a component or assembly detail, it is assumed to be the simplest possible adaptation of an already accepted component or assembly detail. The thesis is organized as followings: Chapter 1: an introduction to the research on ancient Chinese architecture. Chapter 2: a review of the computer simulation and representation of historic architecture. Chapter 3: a discussion about the methodology on the concept of "building an ideal model", and the methodology for modelling when there is a lack of information. Chapter 4: a record of the digital modelling process. Chapter 5: discussions on and conclusions of the research. The thesis has an accompanying CD which contains the representation information, including: - A 2D 'Flash' presentation that shows the brief contents of the research. - 3D animations that represent in detail the timber structure and the assembly process. - A database that represents the structural components and their relations. / Thesis (M.Arch.)--School of Architecture, Landscape Architecture & Urban Design, 2005.
210

Load sharing and system factors for light-frame wall systems

Yu, Guangren 17 January 2003 (has links)
A considerable amount of research has focused on load-sharing and system effects in repetitive-member wood floor systems subject to transverse loading. However, relatively few studies have been conducted to investigate load-sharing and system effects in repetitive-member wall systems which may be subject to combined transverse and gravity (vertical) loading, and which may have different boundary conditions from floors. This research investigates load-sharing and system effects in light-frame wood wall systems and seeks to develop repetitive-member system factors for codified design that rationally account for load sharing and other system effects. These factors are intended for use in the design of individual wall members, much as repetitive-member factors are used in the design of parallel-member floor and roof systems. As part of this research, an analytical model was developed to account for partial composite action, two-way action, and openings in the wall system. The model was validated using experimental test results and was shown to be able to predict reasonably well the response of light-frame wall systems. The model was then incorporated into a Monte Carlo simulation to perform reliability analyses of light-frame wall systems. Since the structural model is complex, and including a time-history analysis within the time-dependent simulation was not computationally practical, the load combination issue was considered separately from the reliability analysis. Sensitivity studies were conducted to investigate how different system parameters affect strength and reliability of light-frame wall systems. The reliability of light-frame wall systems was next evaluated using a portfolio of representative light-frame wall systems designed according to current code provisions. This portfolio approach was also used in evaluating system factors for light-frame wall systems. Thus, two different approaches (a reliability-based approach and a strength-ratio approach) were considered for developing system factors for member-design to account for load sharing, partial composite action and other system effects. Using the strength-ratio approach, a new framework for system factors (i.e., partial system factors) is suggested in which the effects of partial composite action, load sharing, load redistribution and system size (number of members) are treated separately. / Graduation date: 2003

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