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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.
1

Healthy transportation - healthy communities: developing objective measures of built-environment using GIS and testing significance of pedestrian variables on walking to transit

Maghelal, Praveen Kumar 15 May 2009 (has links)
Walking to transit stations is proposed as one of the strategies to increase the use of transit. Urban planners, transportation planners, environmentalists, and health professionals encourage and support environmental interventions that can reduce the use of cars for all kinds of trips and use alternative modes of travel such as walking, biking, and mass-transit. This study investigates the influence of the built-environment on walking to transit stations. Transit-oriented communities at quarter and half-mile distances from the Dallas Area Rapid Transit (DART) station in Dallas, Texas, were analyzed to identify the relation of various constructs of built-environment on walking to the DART stations. Twenty-one pedestrian indices were reviewed to develop a comprehensive list of 73 built-environment variables used to measure the suitability to walk. This study aims to objectively measure built-environment using spatial data. Based on this criterion the total number of variables was narrowed to 32. Walking to transit, calculated as a percentage of transit users who walk to the DART LRT stations, was used as the dependent variable. The number of stations in operation and used for analysis in this study is 20(n). Therefore, bootstrapping was used to perform the statistical analysis for this study. The final pattern of variable grouping for the quarter-mile and the half-mile analysis revealed four principal components: Vehicle-Oriented Design, Density, Diversity, and Walking-Oriented Design. Bootstrap regression revealed that density ( = -0.767) was the only principal component that significantly (p<0.05) explained walking to transit station at quarter-mile distance from the station. At half-mile distance built-environment variables did not report any significant relation to walking to transit. The present study revealed that mere increase of density should not be taken as a proxy of increase in walking. Environmental interventions that can promote walking should be identified even at locations with high density. Further studies should use advanced statistical techniques such as Hierarchical Linear Modeling or Structural Equation Modeling to test the relationship of both the principal components and the individual variables that define the principal component to clearly understand the relationship of built-environment with walking to transit station.
2

Healthy transportation - healthy communities: developing objective measures of built-environment using GIS and testing significance of pedestrian variables on walking to transit

Maghelal, Praveen Kumar 15 May 2009 (has links)
Walking to transit stations is proposed as one of the strategies to increase the use of transit. Urban planners, transportation planners, environmentalists, and health professionals encourage and support environmental interventions that can reduce the use of cars for all kinds of trips and use alternative modes of travel such as walking, biking, and mass-transit. This study investigates the influence of the built-environment on walking to transit stations. Transit-oriented communities at quarter and half-mile distances from the Dallas Area Rapid Transit (DART) station in Dallas, Texas, were analyzed to identify the relation of various constructs of built-environment on walking to the DART stations. Twenty-one pedestrian indices were reviewed to develop a comprehensive list of 73 built-environment variables used to measure the suitability to walk. This study aims to objectively measure built-environment using spatial data. Based on this criterion the total number of variables was narrowed to 32. Walking to transit, calculated as a percentage of transit users who walk to the DART LRT stations, was used as the dependent variable. The number of stations in operation and used for analysis in this study is 20(n). Therefore, bootstrapping was used to perform the statistical analysis for this study. The final pattern of variable grouping for the quarter-mile and the half-mile analysis revealed four principal components: Vehicle-Oriented Design, Density, Diversity, and Walking-Oriented Design. Bootstrap regression revealed that density ( = -0.767) was the only principal component that significantly (p<0.05) explained walking to transit station at quarter-mile distance from the station. At half-mile distance built-environment variables did not report any significant relation to walking to transit. The present study revealed that mere increase of density should not be taken as a proxy of increase in walking. Environmental interventions that can promote walking should be identified even at locations with high density. Further studies should use advanced statistical techniques such as Hierarchical Linear Modeling or Structural Equation Modeling to test the relationship of both the principal components and the individual variables that define the principal component to clearly understand the relationship of built-environment with walking to transit station.
3

Avaliação de parâmetros ergonômicos : vibração e ruído em roçadoras laterais /

Schutzer, Victor Manieri. January 2018 (has links)
Orientador: João Eduardo Guarnetti dos Santos / Banca: Bento Rodrigues de Pontes Junior / Banca: Ricardo Carvalho Tosin / Resumo: A crescente mecanização na agricultura mundial foi acompanhada do aumento do número de acidentes e fez com que elevasse a preocupação com a saúde de seus operadores, já que tais trabalhadores estão expostos aos riscos que esse tipo de atividade proporciona. Alguns dos graves problemas que são gerados pelos equipamentos agrícolas é a alta vibração e ruído a que os operadores ficam expostos na sua jornada de trabalho. A vibração que atinge os trabalhadores pode ser considerada como um distúrbio, já que é responsável por grandes prejuízos à saúde do ser humano, estando diretamente relacionada com a fadiga do trabalhador. O ruído, considerado como um som indesejável, é outro problema gerado por máquinas motoras e responsável por lesão no aparelho auditivo e, até mesmo, por estresse psicofisiológico. Para o presente trabalho, analisou-se os riscos físicos que a vibração e o ruído causam em operadores de roçadoras motorizadas. Foram feitas análises de situações reais que os usuários deste tipo de máquina enfrentam no seu dia a dia de trabalho, para que se possa tirar conclusões da possibilidade de efeitos danosos. Para a pesquisa utilizou-se um acelerômetro de três eixos - HVM 100, marca Larson Davis, para mensurar a vibração captada pela mão do operador e um medidor de pressão sonora, marca Instrutherm, modelo DEC-460 para mensurar o ruído causado pela roçadora. Para a análise da vibração captada pela mão dos operadores foi utilizada a norma internacional ISO 5349 (2001) - Vibraçã... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increasing mechanization in world agriculture was accompanied by an increase in the number of accidents has caused concern about the health of its operators, as these workers are exposed to risks that this type of activity provides. Some of the serious problems that are generated by agricultural equipment are the high vibration and noise to which operators are exposed in their work. The vibration that affects the workers can be considered as a disorder, since it is responsible for major damages to the health of human beings, being directly related to worker fatigue. Noise, regarded as an unwanted sound, is another problem caused by motorized machines and responsible to hearing damage and even to psychophysiological stress. For this study, a physical risks analysis was made. So it is possible to determine the damage that vibration and noise can cause in motorized brushcutter's operators. Real situations of the daily work that these users go through were analyzed, so that conclusions can be made of the possibility of harmful effects. For the research, an accelerometer of three axes - HVM 100, Larson Davis brand, was used to measure the vibration captured by the hand of the operator and a sound pressure meter, Instrutherm brand model DEC-460, was used to measure the noise caused by brushcutters. For the vibration analysis captured by the hand of the operators, the international standard ISO 5349 (2001) - Mechanical Vibration - Measurement and Evaluation of Human Exposure to ... (Complete abstract click electronic access below) / Mestre
4

A Comparative Study of the Oxygen Uptake Between Nonmotorized and Motorized Treadmills

Wood, Michael S. 01 May 1996 (has links)
The purpose of this study was to determine the effects of nonmotorized treadmill walking and motorized treadmill walking on YO, results, measured in ml•kg·'·min·•, of males and females, ages 20-30 at Utah State University, Logan, Utah, USA. The participants were required to walk at a pace of 3 miles per hour and 13% grade for a total exercise time of 9 minutes. The exercise time was broken up with 3-minute recovery periods. Oxygen uptake was measured continuously using a metabolic measurement cart. The data obtained from the metabolic cart were correlated for each treadmill to determine the degree of relationship. A 1 test for correlated means was used to determine if there was a significant difference, alpha < 0.05, when measuring YO, and metabolic (MET) results. A significantly low correlational coefficient was found when the Pro form Dual Motion Crosswalk Cross Trainer motorized treadmill (CW TM) V02 and MET results were compared with the Jane Fonda nonmotorized treadmill (Jane TM) and Voit 502 MD nonmotorized treadmill (Voit TM) YO, and MET results (r = 0.3, Q < 0.0001). These results enabled the researchers to reject the null hypotheses, which stated there would be no significant difference and a high positive correlation between nonmotorized and motorized treadmill V02 and MET results. Standard mean difference effect sizes were calculated for the nonmotorized treadmills versus the motorized treadmill. An effect size of 1.62 was found when both nonmotorized treadmills were compared with the motorized treadmill. This, combined with the significant difference, Q < 0.0001 , provided confidence that a Type I error was avoided. Therefore, the results of this research study show a significant difference in V02 and METs measured on a nonmotorized treadmill when compared with a motorized treadmill.
5

Development of an Improved Medical Transport Device: Stair Chair

Dunn, Taylor B. 02 May 2011 (has links)
No description available.
6

Non Motorized Transport Planning for an Indian City

Rahul, T M January 2015 (has links) (PDF)
Indian cities are currently facing various transportation issues like congestion, pollution, urban inequity, high fatality rate due to accidents etc. because of an increase in the ownership of private motor vehicles and their usage. This has prompted many policy makers to search for alternate modal options that are more sustainable than motorized modes. Non Motorized Transport (NMT), which includes mainly walking and cycling in an urban context, do not produce many of the issues associated with motorized modes like congestion, pollution, fatal accidents etc. But, promotion of NMT requires a clear-cut planning strategy, with a lucid understanding of various strategies and their effect on the NMT usage. Present study tries to answer certain pertinent questions, particularly with respect to walking and cycling, which can arise while preparing a plan for promoting NMT in Indian cities. The following are the questions that the author seeks to answer in the present study. 1) Which are the areas inside a city that a planner shall target for promotion of NMT?2) Where shall a planner locate the infrastructures for NMT in these areas?3) What may be the possible impacts of providing these NMT facilities?4) What may be the possible effect of built environment factors on the choice of NMT? Providing NMT infrastructures requires knowledge of location characteristics such as the trip distance of NMT. Present study tries to elicit the existing distance characteristics of walking and cycling in terms of an acceptable trip distance. The household travel data of Bangalore city, for the year 2009, are used in the study. First, a description and a statistical analysis of the walking and cycling trip distances across the subcategories of socio-demographic and regional factors is done. Secondly, the acceptable distance is computed from the cumulative trip length distribution based on the results of the statistical analysis. The socio-demographic and regional factors used in the study include purpose, age, gender, educational level, occupational status, and motor vehicle ownership. The major results include a significant difference between the mean trip distances on foot for the subcategories of variables such as gender (z value, 4.94), whether the respondent owned a private vehicle (z value, -21.2), and whether the trip was made inside the Central Business District (CBD) (z value, -3.93). One of the major implications of this study pertains to requirement of a footpath around main activity centers like bus stations, at least up to a distance of 1385 meters (maximum value for walking as the main mode) and around the bus stops, at least up to a distance of 750 meters (maximum value for walking as the access mode). Next, the present study analyzes the influence of built environment factors –density and diversity -on the mode choice and trip distance of the residents in the Bangalore city. The built environment factors are analyzed, for their marginal effects in the presence of various socio-demographic and alternative attributes, for the two segments -respondents owning at least a personal vehicle and respondents not owning any personal vehicle. The density used is the total density, which was the sum of population density in a zone and employment density in a zone. The diversity index, which was an explainer of the land-use mixture, was set such that, when a zone with small area had employment opportunities comparable with its population, the diversity index would be high. When tested on a holdout sample other than the ones used in the estimation of the mode choice model, for the vehicle-owning group, the model estimated produced a validation accuracy of 93% and 91% respectively for two-wheelers and walking. For the vehicle non-owning group, the prediction success rate was highest for walking (97%), and lowest for public transit (84%). For the vehicle non-owning group, an increase in the density increased the trip distance (parameter values of 0.016 for total density at origin and 0.002 for total density at destination) and decreased the NMT usage (parameter values of -0.036 and 0.038 respectively for cycling and walking for total density at origin, and -0.092 and 0.073 respectively for cycling and walking for total density at destination), but for the vehicle-owning group, the inverse was true. The results for the vehicle non-owning group highlighted the requirement of a policy framework to control the employment and housing location of them in order to reduce their trip distance. In the mode choice model for the personal vehicle-owning group, the similarity between the parameters of the built environment factors across the two-wheeler and NMT reflected the need for adopting policies that would change the attitude of people towards NMT. Also, the trip distance model determined that females preferred a shorter working distance, with a parameter value -0.109 for the vehicle-owning group and -0.04 for the vehicle non-owning group, when compared with males. Lastly, the study develops a methodological framework to determine the sustainability impact on providing NMT infrastructures using a Composite Sustainability Index (CSI). More specifically, the study develops a methodological framework to determine the variation in the CSI on providing NMT -walking and cycling – infrastructure. The methodology establishes a link between the proposed NMT infrastructures and the CSI using two explanatory indicators: 1) number of motorized vehicles and 2) vehicle-kilometers travelled by the motorized modes. The main components of the framework include the estimation of a mode choice model for a study area, calculation of the explanatory indicators for the scenarios before and after providing NMT infrastructures, and determination of the sustainability impact. The proposed framework, along with the acceptable distance determined in the earlier step, is then used to determine the sustainability impact on providing NMT facilities, for a future scenario, inside the CBD of Bangalore and around the bus stops carrying trips to the CBD. Three case studies are presented with the first one considering only intra zonal (CBD) trips, the second one considering only inter zonal trips having CBD as destination, and the third one considering both above mentioned the trips. The results of all the three case studies found an increase in the CSI (0.002 for the first case study, 0.076 for the second case study, and 0.100 for the third case study) for the peak-hour trips inside the CBD, on providing NMT infrastructures. This increase showed an improvement in the sustainability. Further, for the case study 1, which consisted of high percentage of short distance trips, the major beneficiaries of the NMT infrastructures were the low-income group. There was a reduction in public transport trips, of which the main contributors were the low-income group, from 142706.2 to 96410.2.
7

Evaluating bicycle accessibility and bike-bus integration infrastructure : Saskatoon, SK, 2006

MacIntyre, Stephen Joseph 15 January 2007
The study proposes an application of Talens (2003) methodological framework for assessing neighbourhood-level (i.e., non-motorised mode) accessibility, and offers recommendations for improving non-motorized transportation (NMT) accessibility to enhance multimodal integration between bicycles and buses in contemporary North American suburban neighbourhoods. Accessibility (or access) is defined as the average travel time or distance between a given origin and destination along the shortest available street network route. The study considers characteristics of the transportation network such as available route directness, facilities, and transit service provision to determine their impacts on bicycle access. A further methodology for comparing bicycle versus bus modal efficiencies within suburban contexts is developed and applied to the case study. A review of approaches designed to promote bicycling while discouraging personal automobile use provides a toolbox of proven treatments that are applied to a case study of Saskatoon, Saskatchewan a city of approximately 200,000 people. The approach provides a process that can be used by city or transit planners to identify neighbourhoods that lack sufficient access and apply treatments that improve bicycle accessibility and bicycle-transit integration. Results suggest existing potential for the bicycle as an access mode within contemporary suburban neighbourhood transportation networks. The case study supports the notion that suburban bicycle-bus integration could be used as a viable alternative to automobiles for daily home-to-node activity trips, and raises questions about the current allocation of public transit service to suburban routes within the context of the case study. Discussion and conclusions suggest directions for future research in this field of sustainable urban transportation planning.
8

Evaluating bicycle accessibility and bike-bus integration infrastructure : Saskatoon, SK, 2006

MacIntyre, Stephen Joseph 15 January 2007 (has links)
The study proposes an application of Talens (2003) methodological framework for assessing neighbourhood-level (i.e., non-motorised mode) accessibility, and offers recommendations for improving non-motorized transportation (NMT) accessibility to enhance multimodal integration between bicycles and buses in contemporary North American suburban neighbourhoods. Accessibility (or access) is defined as the average travel time or distance between a given origin and destination along the shortest available street network route. The study considers characteristics of the transportation network such as available route directness, facilities, and transit service provision to determine their impacts on bicycle access. A further methodology for comparing bicycle versus bus modal efficiencies within suburban contexts is developed and applied to the case study. A review of approaches designed to promote bicycling while discouraging personal automobile use provides a toolbox of proven treatments that are applied to a case study of Saskatoon, Saskatchewan a city of approximately 200,000 people. The approach provides a process that can be used by city or transit planners to identify neighbourhoods that lack sufficient access and apply treatments that improve bicycle accessibility and bicycle-transit integration. Results suggest existing potential for the bicycle as an access mode within contemporary suburban neighbourhood transportation networks. The case study supports the notion that suburban bicycle-bus integration could be used as a viable alternative to automobiles for daily home-to-node activity trips, and raises questions about the current allocation of public transit service to suburban routes within the context of the case study. Discussion and conclusions suggest directions for future research in this field of sustainable urban transportation planning.
9

Improving Cable Logging Operations for New Zealand’s Steep Terrain Forest Plantations

Harrill, Hunter January 2014 (has links)
Cable logging will become more important as harvesting shifts to greater annual proportions on steep terrain in New Zealand. The costs of cable logging are considerably higher than that of conventional ground-based methods. Improving cost-effectiveness has been identified as key to ensuring the forestry industry remains cost competitive in the international market. This thesis focuses on ways to better understand and improve cable logging methods by specifically focusing on rigging configurations. The investigation was conducted through a comprehensive literature review, an industry survey to establish current use and preferences, a Delphi survey with experts to establish actual advantages and disadvantages, scale model testing to establish some fundamental knowledge of tension to deflection relationship, and finally a series of targeted case studies to establish both productivity and skyline tension in actual operations. Each of these aspects of the research topic employed different methodology. The literature review highlighted the most relevant research relating to cable logging world-wide spanning nearly a century. Various research papers, manuals, books and computer software were summarized. While many aspects of cable yarding operations have been investigated, much of it focusing on various aspects of operational efficiency through case studies, there is very limited information with regard to rigging configurations. The survey of 50 cable logging practitioners determined what rigging configurations were commonly used in New Zealand. It includes their perceived advantages and disadvantages for varying levels of deflection, but also for specific scenarios such as pulling away from native forest boundaries and flying logs over a stream. Results showed that there were many conflicting perceptions about rigging configuration options. Using an expert panel, a Delphi process was used to derive consensus on what advantages were truly unique to each configuration. This allowed the longer lists of perceived advantages from the industry survey to be pared down to a concise list of ad/disadvantages that will be used in the updating of the Best Practice Guidelines for Cable Logging. To increase our fundamental understanding of tension / payload / deflection relationships, an experiment was conducted in a controlled environment. Using a model yarder in a lab and continuous tension and video recording devices, the dynamic skyline behavior of three similar configurations were tested: North Bend, South Bend and Block in the Bight. The tensions were compared by use of a two-way analysis of variance, which indicated configuration and choker length were significant variables in some but not all of the dynamic load tests. Results also showed that some configurations performed better than others in minimizing the shock loads due to dropping into full suspension, impact with ground objects, and breakout during bridling. Finally, a series of eight studies were conducted on targeted logging operations where relevant stand and terrain parameters were related to the continuous skyline tension monitoring, and recording of productivity through time study. The three targeted configurations included (1) North Bend, (2) Standing skyline using a motorized slack-pulling carriage and (3) a live skyline using a motorized grapple carriage. Results showed that peak and average tensions, as well as amplification factors and the payload to tension relationship, varied between configurations. The study also showed that tensions could be collected to compute measures of payload and tension efficiency, which provided insight into operational performance. The safe working load was exceeded in 53% of all cycles studied and across seven of eight study sites and 14 of 16 spans. Cycle times were significantly different between rigging configurations and that production information could be used to compute measures of labor and energy consumption as well as payload and tension efficiency; which also provide insight into operational performance. The industry should give serious consideration to the use of tension monitors. Tension monitors have many benefits and have the potential to improve cable logging operations in New Zealand. Monitoring tensions can help one learn new techniques or methods (i.e. rigging configurations), help improve payload analysis software for future planning and help evaluate new technology and machinery.
10

Impacto da hierarquia viária orientada para o automóvel no nível de serviço de modos não motorizados / Impacts of the auto-oriented street hierarchy on the level of service of non-motorized modes

Yuassa, Vanessa Naomi 03 April 2008 (has links)
O objetivo desse trabalho é a verificação da hipótese de que, ao se basear na hierarquia viária direcionada ao automóvel, as estratégias de planejamento urbano e de transportes vigentes produzem impactos negativos no nível de serviço de outros modos de transporte, sobretudo os modos não motorizados. O método proposto, aplicado em um estudo de caso realizado na cidade de São Carlos, no estado de São Paulo, envolveu três etapas: (1) caracterização dos níveis de serviço das redes urbanas em análise para os modos a pé, bicicleta e automóvel; (2) análise exploratória dos resultados obtidos na etapa inicial através de geração de mapas e gráficos; e (3) comparação detalhada dos valores obtidos. Foram selecionadas cinco áreas de diferentes níveis de renda para o estudo de caso. Em cada uma delas foram identifi-cados diferentes tipos de vias (local, coletora, radial, estrutural e perimetral), e sele-cionados segmentos para compor uma amostra de 30% da extensão total das vias. A primeira atividade exigiu o desenvolvimento e adaptação de metodologias para a avaliação do nível de serviço dos modos considerados no estudo. Mais de trezentos e cinqüenta segmentos de vias foram examinados. Os resultados obtidos na análise exploratória apontaram que inúmeros segmentos com altos valores de NS para o modo automóvel tinham baixos valores de NS para o modo a pé, o que em princípio confirma a hipótese inicial. As análises detalhadas deram suporte a essa avaliação. No entanto, elas se restringiram às vias locais, o que aponta para a necessidade de estudos complementares nos demais tipos de vias. / The objective of this work is to verify the hypothesis that the current urban and transportation planning strategies based on the auto-oriented street hierarchy produce negative impacts on the level of service of other transportation modes, particularly the non-motorized modes. The proposed method, which was applied in a case study in the city of São Carlos, in the state of São Paulo, involved three steps: (1) the characterization of the level of service for pedestrians, bicycles and automobiles in the urban networks under analyses; (2) an exploratory analysis of the results obtained in the first step through maps and graphs; (3) a detailed comparison of the values found. Five areas with different income levels were selected for the case study. In each one of them five types of streets were identified (local streets, collector streets, minor arterials or radial streets, principal arterials or structural streets, and perimetral streets) and a sample of street segments covering 30% of the total length of the streets was selected. The first activity required the development and adaptation of methodologies for the assessment of the level of service of the transportation modes considered in the study. Over three hundred and fifty street segments were examined. The results obtained in the exploratory analyses have shown that several street segments with high values of level of service for the automobile had low values of level service for the pedestrians, thus confirming the initial hypothesis. The detailed analyses conducted in the sequence supported that observation. However, they were conducted only for the local streets, what indicates the need of further studies in the other types of streets.

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