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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.
11

The behaviour of multi-storey composite steel framed structures in response to compartment fires

Lamont, Susan January 2001 (has links)
For many years, the ability of highly redundant composite framed structure to resist the effect of a fire have been undervalued and misunderstood. A great deal of work on the behavior of composite steel-concrete structures in fire has been developed since the Cardington frame fire tests (UK) conducted in the 1990s.
12

Tecnologia de fachada: cortina com placas de grês porcelanato. / Technology of porcelain tiles curtain wall.

Amaury Antunes de Siqueira Junior 28 February 2003 (has links)
O trabalho apresenta o estado-da-arte das fachadas-cortina executadas com placas de grês porcelanato, discutindo os principais parâmetros para a elaboração de projetos e produção desta tipologia de revestimentos. Acredita-se ser este um dos primeiros trabalhos acadêmicos elaborados no Brasil sobre o assunto, pretendendo-se contribuir quando da implantação desse sistema no país. Procura-se estabelecer os principais conceitos e definições sobre as fachadas-cortina e fachadas ventiladas, objetivando fundamentar a utilização desses termos que vêm sendo empregados sem precisão pelo meio técnico brasileiro. São abordadas as principais características e propriedades dos componentes, elementos construtivos e dispositivos empregados, como também os principais requisitos a serem considerados quando da elaboração do projeto. São destacadas as vantagens relativas desta tecnologia construtiva quando comparada aos revestimentos tradicionais aderidos, ressaltando-se sua importância como alternativa e potencialidades quando comercializado como um sistema de produção. / This report approaches the state-of-art of the porcelain tiles curtain wall. Both design and installations methods are discussed, including main features and properties of the components, elements and devices necessary. Main requirements considered to the design process are also take into consideration. It is believed that this study is one of the first academic studies developed in Brazil concerning this theme, and it is intended to contribute to the implementation of this system in the country. It aims at establishing the main concepts and the definitions on the curtain walls and ventilated facades. The prime objective is to base the correct use of these terms, since they have been used without accuracy by the Brazilian technicians. main features and properties of the components, elements and devices necessary. Main requirements considered to the design process are also take into consideration. Several advantages concerning this type of cladding are emphasized when compared with traditional coverings, standing out the comportance of the method as an interesting technology alternative.
13

Tecnologia de fachada: cortina com placas de grês porcelanato. / Technology of porcelain tiles curtain wall.

Siqueira Junior, Amaury Antunes de 28 February 2003 (has links)
O trabalho apresenta o estado-da-arte das fachadas-cortina executadas com placas de grês porcelanato, discutindo os principais parâmetros para a elaboração de projetos e produção desta tipologia de revestimentos. Acredita-se ser este um dos primeiros trabalhos acadêmicos elaborados no Brasil sobre o assunto, pretendendo-se contribuir quando da implantação desse sistema no país. Procura-se estabelecer os principais conceitos e definições sobre as fachadas-cortina e fachadas ventiladas, objetivando fundamentar a utilização desses termos que vêm sendo empregados sem precisão pelo meio técnico brasileiro. São abordadas as principais características e propriedades dos componentes, elementos construtivos e dispositivos empregados, como também os principais requisitos a serem considerados quando da elaboração do projeto. São destacadas as vantagens relativas desta tecnologia construtiva quando comparada aos revestimentos tradicionais aderidos, ressaltando-se sua importância como alternativa e potencialidades quando comercializado como um sistema de produção. / This report approaches the state-of-art of the porcelain tiles curtain wall. Both design and installations methods are discussed, including main features and properties of the components, elements and devices necessary. Main requirements considered to the design process are also take into consideration. It is believed that this study is one of the first academic studies developed in Brazil concerning this theme, and it is intended to contribute to the implementation of this system in the country. It aims at establishing the main concepts and the definitions on the curtain walls and ventilated facades. The prime objective is to base the correct use of these terms, since they have been used without accuracy by the Brazilian technicians. main features and properties of the components, elements and devices necessary. Main requirements considered to the design process are also take into consideration. Several advantages concerning this type of cladding are emphasized when compared with traditional coverings, standing out the comportance of the method as an interesting technology alternative.
14

The Performance of Rainscreen Walls in Coastal British Columbia

Finch, Graham January 2007 (has links)
This thesis examines the widespread moisture problems which emerged over the past twenty years in buildings throughout coastal British Columbia, commonly known as ‘leaky condos’. A literature review of building physics and a historical review of wood-frame construction in North America provide background for this review. The purpose of this work is to report and interpret the performance of rainscreen walls in the coastal climate of Vancouver BC, based on extensive field data from five local buildings constructed or rehabilitated with rainscreen wall assemblies. Hygrothermal data was collected within exterior walls, and corresponding environmental data was recorded for each building. Driving rain loads at the five buildings across the city are calculated and compared to Vancouver airport data. Site factors are shown to have a significant impact on driving rain load, wind speed and direction. The WUFI 4.1 hygrothermal model was compared with the field data collected and found to be accurate at predicting past performance. Applying this validated model to each wall assembly, further simulations were performed to determine the impact of boundary conditions and assembly details on wall performance. Field measurements and modeling show that ventilated and drained claddings (i.e. rainscreen) reduce the sensitivity of wood frame buildings to moisture damage. Ventilation of the cladding is shown to be particularly important and natural buoyancy forces (from temperature and humidity differences between cavity and exterior) are usually sufficient to provide good drying. Exterior insulation is shown to further improve rainscreen wall performance by increasing the drying potential of the sheathing to both the exterior and interior. Additional work performed included material testing of fiberglass-faced gypsum sheathing and air-leakage testing of individual suites in the monitored buildings. Elevated interior humidity, resulting from inadequate ventilation, is shown to be exacerbated by inter-zonal air-flow in multi-unit residential buildings.
15

Hygrothermal Performance of Insulated, Sloped, Wood-Framed Roof Assemblies

Schumacher, Christopher James January 2008 (has links)
Roofs are the single enclosure element common to artificial shelters constructed by all cultures in all climate regions. The hygrothermal performance of insulated, sloped, wood-framed roof assemblies has long been of interest to building scientists and building codes alike. Requirements for the ventilation of roof assemblies have been included in building codes for more than 50 years, however moisture problems still occur. Unvented roof assemblies have been suggested as an alternate and potentially superior solution. While unvented roofs have become relatively common in the warmer southern climates of North America, some technical issues remain unclear and the need exists for further study and demonstration of the hygrothermal performance of both ventilated and unvented roof assemblies in cold northern climates. This thesis seeks to address these issues through a review of existing literature, experience and industry practice, field investigation and measurement, analytical calculation and computer simulations.
16

The Performance of Rainscreen Walls in Coastal British Columbia

Finch, Graham January 2007 (has links)
This thesis examines the widespread moisture problems which emerged over the past twenty years in buildings throughout coastal British Columbia, commonly known as ‘leaky condos’. A literature review of building physics and a historical review of wood-frame construction in North America provide background for this review. The purpose of this work is to report and interpret the performance of rainscreen walls in the coastal climate of Vancouver BC, based on extensive field data from five local buildings constructed or rehabilitated with rainscreen wall assemblies. Hygrothermal data was collected within exterior walls, and corresponding environmental data was recorded for each building. Driving rain loads at the five buildings across the city are calculated and compared to Vancouver airport data. Site factors are shown to have a significant impact on driving rain load, wind speed and direction. The WUFI 4.1 hygrothermal model was compared with the field data collected and found to be accurate at predicting past performance. Applying this validated model to each wall assembly, further simulations were performed to determine the impact of boundary conditions and assembly details on wall performance. Field measurements and modeling show that ventilated and drained claddings (i.e. rainscreen) reduce the sensitivity of wood frame buildings to moisture damage. Ventilation of the cladding is shown to be particularly important and natural buoyancy forces (from temperature and humidity differences between cavity and exterior) are usually sufficient to provide good drying. Exterior insulation is shown to further improve rainscreen wall performance by increasing the drying potential of the sheathing to both the exterior and interior. Additional work performed included material testing of fiberglass-faced gypsum sheathing and air-leakage testing of individual suites in the monitored buildings. Elevated interior humidity, resulting from inadequate ventilation, is shown to be exacerbated by inter-zonal air-flow in multi-unit residential buildings.
17

Hygrothermal Performance of Insulated, Sloped, Wood-Framed Roof Assemblies

Schumacher, Christopher James January 2008 (has links)
Roofs are the single enclosure element common to artificial shelters constructed by all cultures in all climate regions. The hygrothermal performance of insulated, sloped, wood-framed roof assemblies has long been of interest to building scientists and building codes alike. Requirements for the ventilation of roof assemblies have been included in building codes for more than 50 years, however moisture problems still occur. Unvented roof assemblies have been suggested as an alternate and potentially superior solution. While unvented roofs have become relatively common in the warmer southern climates of North America, some technical issues remain unclear and the need exists for further study and demonstration of the hygrothermal performance of both ventilated and unvented roof assemblies in cold northern climates. This thesis seeks to address these issues through a review of existing literature, experience and industry practice, field investigation and measurement, analytical calculation and computer simulations.
18

Instruments for Scoring Pain, Non-Pain Related Distress, Analgesia, and Sedation in Pediatric Mechanically Ventilated Patients and their Efficacy and Effectiveness in Practice: A Systematic Review

Dorfman, Tamara L. Unknown Date
No description available.
19

Analysis of heat dissipation from railway and automotive friction brakes

Voller, Gordon Paul January 2003 (has links)
The thesis presents research into the understanding and improvement of heat dissipation from friction brakes. The investigations involved two brake types, considered to be the most thermally loaded and therefore most challenging; axle mounted high speed railway and commercial vehicle disc brakes. All three modes of heat transfer (conduction, convection and radiation) and airflow characteristics have been analysed experimentally and theoretically in order to increase the understanding of heat dissipation. Despite the very practical aspects of this research, a 'generic heat transfer approach' was applied, enabling wider engineering applications of the results. Experimental analyses conducted on a specially developed Spin Rig allowed measurements of cooling and airflow characteristics for different designs. Methodologies have been developed to determine thermal contact resistance, heat transfer coefficients, emissivity and aerodynamic (pumping) losses. Established values and relationships compared very favourably with theoretical work. Analytical, FE and CFD analyses were employed to further investigate design variations and perform sensitivity studies. Inertia dynamometer route simulations provided disc temperatures for validation of the overall work. Recommendations have been made for optimising heat dissipation, by proposing practically acceptable and economically viable design solutions. A proposed ventilated disc design efficiency ratio allows large, high speed ventilated disc designs, to be efficiently and accurately evaluated and compared, providing a valuable disc design optimisation tool. The determination of the methodologies, parameters and functions defining cooling characteristics, enable heat dissipation to be predicted confidently and accurately for brakes and other engineering assemblies at early design stages.
20

The Effects Of Construction Materials On Thermal Comfort In Residential Buildings / An Analysis Using Ecotect 5.0.

Aydin Gezer, Nevin 01 January 2003 (has links) (PDF)
The aim of this study was to provide information about the effects of construction materials on thermal comfort in residential buildings using Ecotect 5.0. Three residential buildings, each of different construction in the province of Yozgat, Turkey were used as study material to this end. At the end of this study, the effects of materials on thermal comfort have been explained by graphical and statistical analysis. Pertinent literature reports that the thermal responses of occupants depend to some extent on the outdoor climate in naturally ventilated buildings with operable windows. Furthermore, an adaptation occurs in these buildings regarding the occupants&amp / #8217 / previous thermal experiences, the availability of control, and shifts in expectations. The study therefore focused on collecting data on both indoor and outdoor air temperature and humidity to show the comfort level in such buildings. By collecting data on 3 houses constructed of different materials the author aimed to show the effects of materials on thermal comfort. The analyses were further extended with computer simulations, which enabled restriction of the parameters on construction materials. The study has shown that in naturally ventilated residential buildings, construction materials affect both thermal comfort and thermal performance of the buildings. Buildings with traditional construction material showed a better performance in achieving the preferred thermal comfort while decreasing energy costs.

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