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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

Tailoring the Acoustic Properties of Truss-Core Sandwich Structure

Lee, Richard 20 November 2012 (has links)
Undesirable cabin noise has an adverse physiological effect on passengers and crews in an aircraft. In order to reduce the noise level, a passive approach using a truss-core sandwich (TCS) panel as a sound insulator is proposed. Design guidelines and analysis methodologies were developed in order to explore the vibro-acoustic characteristics of TCS structure. Its sound isolation properties can be thereby assessed. Theoretical analyses show that the transmission-loss and sound radiation properties of a TCS structure can be represented by the root-mean-square velocity of its surface, and a beam structure analysis is sufficient to reveal many of the important aspects of TCS panel design. Using finite element analysis, a sensitivity study was performed to create design guidelines for TCS structures. Transmission-loss experiments show that the analytical and numerical analyses correctly predict the trend of TCS structure’s vibro-acoustic performance.
12

Tailoring the Acoustic Properties of Truss-Core Sandwich Structure

Lee, Richard 20 November 2012 (has links)
Undesirable cabin noise has an adverse physiological effect on passengers and crews in an aircraft. In order to reduce the noise level, a passive approach using a truss-core sandwich (TCS) panel as a sound insulator is proposed. Design guidelines and analysis methodologies were developed in order to explore the vibro-acoustic characteristics of TCS structure. Its sound isolation properties can be thereby assessed. Theoretical analyses show that the transmission-loss and sound radiation properties of a TCS structure can be represented by the root-mean-square velocity of its surface, and a beam structure analysis is sufficient to reveal many of the important aspects of TCS panel design. Using finite element analysis, a sensitivity study was performed to create design guidelines for TCS structures. Transmission-loss experiments show that the analytical and numerical analyses correctly predict the trend of TCS structure’s vibro-acoustic performance.
13

Surficial geology of the Komie Creek map area and an investigation of an ice-contact glaciofluvial delta, northeast British Columbia (NTS 94P/05)

Demchuk, Tania Ellen 02 June 2011 (has links)
The Komie Creek map area was fully glaciated by the Laurentide Ice Sheet (LIS) during the Late Wisconsinan Fraser Glaciation. Ice flow during the glacial maximum was towards the southwest, as indicated by the orientation of streamlined landforms on the Etsho Plateau. At some time after the Fraser Glaciation maximum, the LIS divided into two lobes (upland and lowland). The subsequent landform assemblages, highlighted well in LiDAR imagery, provide evidence that the upland lobe retreated to the northeast and the lateral margin of the lowland lobe dropped to the southwest. Organic deposits are the dominant surficial material type in the Komie Creek map area. They have accumulated and been deposited on poorly drained clay and silt-rich morainal and glacio-lacustrine deposits. Morainal deposits are the next most common surficial material type in the area and dominate along the top of the Etsho Escarpment and in the northeast corner of the study area. Glaciofluvial deposits are rare. During ice retreat, an ice-marginal lake formed in the south-central part of the study area where the lowland lobe prevented drainage of meltwater out of the area. An aerially extensive landform, interpreted as an ice-contact glaciofluvial delta complex, was deposited into this dynamic glacial lake. The lake levels rose abruptly several times during delta deposition as a result of large west-flowing outburst floods in the Cabin Creek melt water channel, generated when a glacial lake breached its margins on or under the upland lobe. The delta is composed of several lobate landforms that sedimentologically are highly variable. This thesis presents a new, detailed 1:50,000-scale surficial geology map for the Komie Creek map area. This map was generated using aerial photographs, LiDAR DEMs, ground-based geophysics and field observations. This research also contributes to an increased understanding of the sedimentology and internal structure of ice-contact glaciofluvial deltas. / Graduate
14

(Re)Connect: Architecture and the Senses

Snyder, Elyse 14 June 2013 (has links)
I live in a society where a state of multi-tasking and over-stimulation is common. I am inundated with excessive information and seemingly addicted to distraction. My love affair with hi speed digital devices devours all sense of time and space. But in the process of making all information available to everyone, all the time, we are losing our connection with the value of direct experience. What I can see, feel, taste, smell, touch and hear is losing significance and with this loss I am becoming isolated from my own nature and perhaps even my own body. In response to this contemporary condition this thesis proposes a place dedicated to rediscovering our innate sense of rhythm and to re-connecting with our place in the cosmos. This is not intended as a rejection of current technologies, but rather a place that examines the potential of architecture to bring us into the present moment. In doing so we are able to attend to the experience of being in our body and moving from moment to moment in the world; we learn to slow down and enjoy the incremental life of our senses. The site for this exploration is an island in the rocky landscape of the Canadian Shield. Known as Twin Island, this place is the site of my family's cabin where I spend each summer. The journey to the island and the place itself are both a physical and spiritual symbol of transformation; of disconnecting then re-connecting. Architecture is used as an instrument to heighten one’s awareness of the primordial power of water, stone, fire and darkness to spark the cosmological imagination. Sinking deeply into her bed she penetrates earth, rock and ancient memory. Here, she finds her place. This is ‘architecture minimum’; we are simply sheltered within the expanse of the universe.
15

Análise de cockpits de ônibus a partir das demandas dos motoristas e características da tarefa

Basso, Claudia Rafaela January 2018 (has links)
Os motoristas de ônibus apresentam problemas de saúde física e psicológica decorrentes da exposição a fatores relacionados com a organização do trabalho e com a própria configuração do ônibus, mais especificamente da cabine, onde realizam suas atividades. Os projetos das cabines dos ônibus e do seu cockpit, interface através da qual o motorista envia comandos para o ônibus, normalmente desconsideram a opinião do motorista e a relação entre produto/usuário/contexto de uso real, fundamental para garantir um projeto de interface adequado, segundo os conceitos de ergonomia e design. Assim, esta pesquisa tem como objetivo estudar e determinar as demandas dos motoristas de transporte rodoviário e urbano de passageiros com relação aos cockpits de ônibus, a fim de propor melhorias considerando as características da tarefa e a opinião dos motoristas com relação ao seu conforto e desempenho. Participaram do estudo duas empresas de transporte de passageiros, uma rodoviária e outra urbana. A metodologia foi estruturada em três fases. A primeira (Pré-análise) teve como objetivo conhecer os cockpits dos ônibus, entender os requisitos considerados na compra de novos veículos e evidenciar as condições do cockpit que atuam na dirigibilidade do veículo. A segunda fase (Análise) consistiu em investigar a percepção dos motoristas com relação aos cockpits dos ônibus, realizado observação in loco, filmagens, entrevistas, questionário e dinâmica do protótipo de papel Na terceira fase (Pós-análise) foi realizada a triangulação dos dados para identificar os fatores de conforto mais relevantes e a comparação dos resultados dos dois grupos de motoristas. Os resultados da dinâmica convergiram com aqueles das entrevistas e questionários evidenciando que, em geral, os motoristas tendem a manter os comandos nos locais em que se acostumaram, modificando somente o posicionamento daqueles que não atendem suas necessidades de forma satisfatória. A principal demanda dos motoristas de transporte rodoviário está vinculada ao posicionamento do comando do ar-condicionado no cockpit e às condições de conforto térmico na cabine. Os motoristas de transporte urbano de passageiros, por outro lado, desejam o reposicionamento do comando do itinerário para um local de fácil alcance e visibilidade quando em sedestação. Esses também relataram desconforto térmico relacionando com a inexistência do dispositivo da ventarola, uma vez que a maioria dos veículos da frota não dispõe de ar-condicionado. Os dois grupos de motoristas indicaram a necessidade de melhorar a visibilidade do painel de instrumentos que, por vezes, é dificultado pelo mau posicionamento do volante. Além disso, os dois grupos de motoristas consideraram o espaço interno da cabine, o ruído, bem como o conforto do banco, características a serem melhoradas. / Bus drivers have physical and psychological health problems due to exposure to factors related to work organization and the configuration of the bus, specifically the cabin, where they carry out their activities. The bus cabins and their cockpit‟s designs, the interface through which the driver sends commands to the bus, usually disregard the driver's opinion and the relationship between product/ user/ context of actual use, primal to ensure a proper interface design, according to the concepts of ergonomics and design. Thus, this research aims to study and determine the demands of road and urban passenger transport drivers in relation to bus cockpits, in order to propose improvements considering the characteristics of the task and the opinion of the drivers regarding their comfort and performance. The study included an urban and a road passenger transport companie. The methodology was structured in three phases. The first one (Preanalysis) had as objective to know the cockpits of the buses, to understand the requirements considered in the purchase of new vehicles and to understand the conditions of the cockpit that act in the dirigibility of the vehicle. The second phase (Analysis) was to investigate the drivers' perception regarding the cockpits of the buses through in loco observation, filming, interviews, questionnaire and paper prototype dynamics In the third phase (Post-analysis) the triangulation of the data was performed to identify the most relevant comfort factors and the results of the two groups of drivers were compared. The results of the dynamics converged with those of the interviews and questionnaires showing that, in general, drivers tend to keep the controls in the places they have become used to, modifying only the positioning of those who do not meet their needs. The main demand of road transport drivers is linked to the positioning of the air conditioning control in the cockpit and the conditions of thermal comfort in the cabin. Passenger urban transport drivers, on the other hand, want the itinerary Command relocate to a location within easy reach and visibility when in the sitting position. They also reported thermal discomfort relating to the absence of ventarola device, since most vehicle do not have air conditioning. The two groups of drivers indicated the need to improve the visibility of the instrument panel which is sometimes hampered by poor steering positioning. In addition, the two groups of drivers considered the interior space of the cabin, the noise as well as the comfort of the seat, features to be improved.
16

Análise de cockpits de ônibus a partir das demandas dos motoristas e características da tarefa

Basso, Claudia Rafaela January 2018 (has links)
Os motoristas de ônibus apresentam problemas de saúde física e psicológica decorrentes da exposição a fatores relacionados com a organização do trabalho e com a própria configuração do ônibus, mais especificamente da cabine, onde realizam suas atividades. Os projetos das cabines dos ônibus e do seu cockpit, interface através da qual o motorista envia comandos para o ônibus, normalmente desconsideram a opinião do motorista e a relação entre produto/usuário/contexto de uso real, fundamental para garantir um projeto de interface adequado, segundo os conceitos de ergonomia e design. Assim, esta pesquisa tem como objetivo estudar e determinar as demandas dos motoristas de transporte rodoviário e urbano de passageiros com relação aos cockpits de ônibus, a fim de propor melhorias considerando as características da tarefa e a opinião dos motoristas com relação ao seu conforto e desempenho. Participaram do estudo duas empresas de transporte de passageiros, uma rodoviária e outra urbana. A metodologia foi estruturada em três fases. A primeira (Pré-análise) teve como objetivo conhecer os cockpits dos ônibus, entender os requisitos considerados na compra de novos veículos e evidenciar as condições do cockpit que atuam na dirigibilidade do veículo. A segunda fase (Análise) consistiu em investigar a percepção dos motoristas com relação aos cockpits dos ônibus, realizado observação in loco, filmagens, entrevistas, questionário e dinâmica do protótipo de papel Na terceira fase (Pós-análise) foi realizada a triangulação dos dados para identificar os fatores de conforto mais relevantes e a comparação dos resultados dos dois grupos de motoristas. Os resultados da dinâmica convergiram com aqueles das entrevistas e questionários evidenciando que, em geral, os motoristas tendem a manter os comandos nos locais em que se acostumaram, modificando somente o posicionamento daqueles que não atendem suas necessidades de forma satisfatória. A principal demanda dos motoristas de transporte rodoviário está vinculada ao posicionamento do comando do ar-condicionado no cockpit e às condições de conforto térmico na cabine. Os motoristas de transporte urbano de passageiros, por outro lado, desejam o reposicionamento do comando do itinerário para um local de fácil alcance e visibilidade quando em sedestação. Esses também relataram desconforto térmico relacionando com a inexistência do dispositivo da ventarola, uma vez que a maioria dos veículos da frota não dispõe de ar-condicionado. Os dois grupos de motoristas indicaram a necessidade de melhorar a visibilidade do painel de instrumentos que, por vezes, é dificultado pelo mau posicionamento do volante. Além disso, os dois grupos de motoristas consideraram o espaço interno da cabine, o ruído, bem como o conforto do banco, características a serem melhoradas. / Bus drivers have physical and psychological health problems due to exposure to factors related to work organization and the configuration of the bus, specifically the cabin, where they carry out their activities. The bus cabins and their cockpit‟s designs, the interface through which the driver sends commands to the bus, usually disregard the driver's opinion and the relationship between product/ user/ context of actual use, primal to ensure a proper interface design, according to the concepts of ergonomics and design. Thus, this research aims to study and determine the demands of road and urban passenger transport drivers in relation to bus cockpits, in order to propose improvements considering the characteristics of the task and the opinion of the drivers regarding their comfort and performance. The study included an urban and a road passenger transport companie. The methodology was structured in three phases. The first one (Preanalysis) had as objective to know the cockpits of the buses, to understand the requirements considered in the purchase of new vehicles and to understand the conditions of the cockpit that act in the dirigibility of the vehicle. The second phase (Analysis) was to investigate the drivers' perception regarding the cockpits of the buses through in loco observation, filming, interviews, questionnaire and paper prototype dynamics In the third phase (Post-analysis) the triangulation of the data was performed to identify the most relevant comfort factors and the results of the two groups of drivers were compared. The results of the dynamics converged with those of the interviews and questionnaires showing that, in general, drivers tend to keep the controls in the places they have become used to, modifying only the positioning of those who do not meet their needs. The main demand of road transport drivers is linked to the positioning of the air conditioning control in the cockpit and the conditions of thermal comfort in the cabin. Passenger urban transport drivers, on the other hand, want the itinerary Command relocate to a location within easy reach and visibility when in the sitting position. They also reported thermal discomfort relating to the absence of ventarola device, since most vehicle do not have air conditioning. The two groups of drivers indicated the need to improve the visibility of the instrument panel which is sometimes hampered by poor steering positioning. In addition, the two groups of drivers considered the interior space of the cabin, the noise as well as the comfort of the seat, features to be improved.
17

Condições do escoamento e de conforto térmico em cabine de aeronave. / Air flow conditions and thermal comfort in aircraft.

Danilo de Moura 19 February 2009 (has links)
A aviação comercial vem experimentando expressivo crescimento com elevado grau de competitividade. Produzir aeronaves com nível de conforto diferenciado transformou-se em importante ferramenta de marketing e de venda. Esta, porém, não é tarefa fácil. Cabines de aeronave apresentam condições de escoamento e de trocas térmicas que tornam bastante difícil prover e avaliar condições de conforto térmico. Para tentar resolver o problema, estudos estão sendo realizados em centros de pesquisa, em colaboração com a indústria aeronáutica. O presente trabalho se insere neste contexto. Neste trabalho foi realizado estudo do escoamento em cabine de aeronave, por meio de medição de variáveis ambientais de cabine, e de conforto térmico utilizando manequim térmico instrumentado e avaliação com pessoas. Para a realização dos ensaios foi projetado e construído mock-up de seção de cabine com 12 lugares. Foram analisadas condições do escoamento e de conforto térmico para duas condições de cabine, 19 e 24 °C. Nos ensaios com pessoas participaram 11 voluntários. Temperaturas equivalentes foram determinadas utilizando-se manequim térmico instrumentado e apresentadas em diagrama de sensação térmica previsto para este fim em norma técnica de veículos. Posteriormente, avaliações subjetivas, com resultados apresentados em diagramas de voto térmico médio (VTM) e de voto de conforto médio (VCM), foram realizadas. Verificou-se que, apesar das condições complexas do escoamento, não ocorreram diferenças significativas de velocidade do ar na região de ocupação e nem de temperatura na direção vertical, que são fatores que poderiam ocasionar grande desconforto. Verificou-se também a ocorrência de uma boa aproximação entre as avaliações de conforto térmico feitas por meio das temperaturas equivalentes e os resultados das análises subjetivas realizadas por meio de questionários. Nas avaliações subjetivas ocorreu um pequeno deslocamento dos resultados para o lado direito no diagrama de VTM. Finalmente, verificou-se que as pessoas preferiram as condições de cabine na temperatura de 19 °C, com votos de conforto médio (VCM) de indiferentes a ligeiramente confortáveis, enquanto na temperatura de cabine de 24 °C as condições foram consideradas ligeiramente desconfortáveis. / The commercial aviation has experienced an expressive growth with a high degree of competitiveness. The production of aircrafts with a higher comfort level has become an important tool for marketing and trading. However, this is not an easy task. Aircraft cabins present airflow and thermal transfer conditions that make quite difficult to provide and to evaluate thermal comfort conditions. In order to try to solve this problem, studies are being performed in research centers, in collaboration with the aeronautical industry. This project is inserted in this context. In this project a study of aircraft cabin airflow, through the measurement of the cabin environmental variables, and the thermal comfort using thermal mannequin and evaluation with people, was accomplished. For the accomplishment of the tests a mock-up of a cabin section with 12 places was projected and built. Conditions of airflow and thermal comfort within two cabin conditions, 19 and 24 °C, were analyzed. The tests with people were performed by 11 volunteers. Equivalent temperatures were obtained by using a thermal mannequin and were presented in a thermal sensation diagram, which had been seen to this purpose in vehicles technical norm. Later on, subjective evaluations, whose results were presented by an mean thermal vote (MTV) diagram and by an mean comfort vote (MCV) diagram, were accomplished. It was verified that, in spite of the complex airflow conditions, significant differences neither of the air velocity in the occupation area nor of the temperature in the vertical direction happened, which are factors that could cause a great discomfort. It was also verified a strong relation between thermal comfort evaluations accomplished through the equivalent temperatures and the results of the subjective analyses accomplished through questionnaires. In the subjective evaluations, a small displacement of the results to the right side in the MTV diagram occurred. Finally, it was verified that the volunteers preferred 19 °C temperature cabin condition, with mean comfort votes (MCV) indicating from indifferent to lightly comfortable conditions, while in the 24 °C cabin the conditions were considered lightly uncomfortable.
18

Rhetorical Strategies and Biblical Hypertextuality in Uncle Tom’s Cabin / Retoriska strategier och biblisk hypertextualitet i Uncle Tom’s Cabin

Ryrberg, David January 2018 (has links)
No description available.
19

Revenue recovery strategies for the Alaska public cabin program

Keeler, Kevin R. January 1987 (has links)
This thesis evaluates a range of policy analysis techniques for application to an issue of policy choice. Divergent premises of two policy alternatives are defined and evaluated using policy impact analysis techniques. The two policy alternatives concern revenue recovery for the Alaska Division of Parks and Outdoor Recreation public use cabin (PUC) program. The lack of a mechanism to recover revenues from program user fees is the primary constraint for the operation and development of the PUC program. The Division has proposed that the Alaska Legislature authorize the implementation of a program receipts policy. Because past legislative initiatives for program receipts have failed, Division staff have proposed implementation of a concessionaire strategy. This thesis determines which policy would ensure the continued operation and development of the PUC program. Classification analysis is used to categorize the operational strengths and weaknesses of each policy, and agency influence over these characteristics. Assumptional analysis is used to define the divergent premises of policy makers. These premises are developed as scenarios of program operations within the framework of a structured policy debate. The impacts of the scenarios are forecast using policy impact analysis techniques, and recommendations are made for an optimum policy strategy. A significant weakness of the program receipts policy is that it is uncertain whether it will be authorized by the Legislature. The failure of Legislative authorization is forecast to have significant mid-term impacts on the PUC program. The primary impact would be the deterioration of facilities; combined with further budget cutbacks, the Division may be forced to abandon the PUC program. Implementation of a concessions strategy would provide a viable alternative for program operations and development. Therefore, concessionaire operation is recommended as a contingency strategy to the program receipts policy. The methods applied to this case study are useful for either the development of, or the critical evaluation of policy directives. The techniques of assumptional analysis or the structured policy debate can be used to identify the assumptions and premises of policy makers. The structured policy debate also provides a means to check the logic of a policy argument. Policy impact analysis provides a means of forecasting or measuring the outcome of implementation. Taken together, the techniques provide for a normative evaluation of issues of policy choice. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
20

Design vysokozdvižného vozíku / Design of fork-lift truck

Vaňková, Jana January 2009 (has links)
This diploma thesis deals with design features of a customs swivel cabin fork-lift truck. Concept is adapted to the technical and ergonomic requirements and the main goal of this concept is to provide original design with a view to the future. The complex concept meets the operational, technical and ergonomic demands of such engines. The project is focused on the design concept and complex contour-composition of the swivel cabin fork-lift truck. Designed of the fork-lift truck stems from the modern technological methods and the construction is ready for production and everyday operating usage, hence the production of this project would be rather expensive for the local market. However, it might be possible to start the production of this fork-lift truck, equipped by various functional components, sometime in the future and such extra functional components will be included as basic accessories of any fork-lift truck.

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