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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.
71

Creative Design of Multi-Speed Hub System for Bicycles

Chi, Yu-Hsin 26 July 2002 (has links)
A multi-speed drive hub is one of important components in transmission system. The purpose of this work is to develop a system methodology for the design of multi-speed bicycle drive hubs. First, identify the basic characteristics and design requirement of multi-speed drive hub. Second, using the useful gear trains. Third, a method is proposed to determine the feasible multi-speed sequence tables for each gear train. Fourth, an analytic method is formulated to synthesize the gear ratios and gear teeth according to a set of desired speed ratios. Fifth, the basic theory for transmission analysis of multi-speed drive hubs will be developed. The results of this work will be benefit to the development and design of multi-speed bicycle drive hubs.
72

Bicycle Rider's Bike Upgrade Model - Grounded Theory Approach

Chou, Meng-hsuan 27 July 2009 (has links)
This research study is focusing on the mid-high priced bikers to understand the process of bicyclers¡¦ purchasing behaviors and decision making. By studying bicyclers¡¦ purchasing behaviors, this research study will provide bikers¡¦ upgrading behavior patterns to bicycle manufacturers. This research study is using half structural formula to interview bikers who have mid-high priced bicycles. Based on process of data analysis in the grounded theory, this research study is using open coding, axial coding, and selecting coding methods to organize the response from participants. After using these three procedures, this research study receives five factors which can be used to form their interconnections. Lastly, this research study builds the upgrade model.
73

Bicyclist understanding, use, and preference of various innovative bicycle infrastructure treatments

Oliver, Jonathan Hunt 08 July 2011 (has links)
As bicycle transportation has increased, especially among commuters, so have the types of bicycle infrastructure facilities increased. This report focuses on the application of several of these innovative bicycle infrastructure treatments in three different scenarios: shared-lane facilities, bicycle-specific facilities, and high-conflict area treatments. The focus treatments include the sharrow, Sharrow Bicycle Priority Lane, Green Bicycle Priority Lane, Bicycles May Use Full Lane sign, green bike lane, bike-box, green lane in a conflict area, and elephant's footprint markings. The goal of this report is to gather how well bicyclists understand their meaning, how they would use each, and which treatments are most preferred among bicyclists. Data for this study was gathered in the form of an online survey administered to 1000 bicyclists of varying levels and purposes from different regions of the country. The survey gathers general rider characteristics, asks how each bicyclist would use each treatment in different traffic speed and volume scenarios, and finally each respondent rates each of the treatments in order of preference. Using the survey results, the effectiveness of each treatment is analyzed in detail by different population segments of those surveyed. Bicyclist riding characteristics and route choice factors are also examined in detail to better understand the sampled population of riders. The results are discussed and conclusions to the effectiveness of each treatment are made.
74

Bike big data : how GPS route data collected from smartphones can benefit bicycle planning

Meyer, Joel Loren 04 December 2013 (has links)
In order to determine the most effective ways to increase ridership in their communities, bicycle planners require quality data on bicycling behavior. Traditional bicycle data collection methods, however, are limited by the large amount of time and expertise required to process and analyze the data, by their inability to provide information at the level of detail needed to understand the complexities of bicycling behavior, and by issues related to sampling bias and poor respondent trip recall. Fortunately, a relatively new method for collecting travel data has emerged that has the potential to provide higher quality and lower cost bicycle data to local planning agencies than has previously been possible with traditional data collection methods: the use of global positioning system (GPS) sensors in smartphones. Researchers at The University of Texas recently evaluated the usefulness of one such smartphone application - “CycleTracks” - to collect bicycle route data. Over 3,600 unique trips were collected from around 300 cyclists in Austin, Texas between May and October, 2011. While they found the CycleTracks app to be useful for collecting a large dataset, to this point there has been only limited analysis of the route data in terms of its usefulness in the planning field. This report will explore the ways in which GPS route data collected from smartphones can address some of the limitations of traditional data collection methods. Austin is used as a case study to show how the GPS route data can be used to plan for network connectivity, to identify barriers in the bicycle network, and to analyze cycling behavior before and after the installation of new facilities. The report finds that despite a number of limitations, smartphone-based GPS data collection has the potential to become an important part of local planning agencies’ regular data collection efforts. / text
75

Automated Route Generation for Bicycle Tours of the United States

Payne, Katherine Carl January 2014 (has links)
Planning a multi-day bicycle tour is a time intensive and difficult task. To enable cyclists to construct their own multi-day tour routes, we propose an automated system which, given an origin, destination, and points of interest, generates detailed bicycle tour routes of minimal perceived exertion. This dissertation is comprised of three bodies of work contained in chapters 2, 3, and 4, respectively. In the first work, chapter 2, we build and test a model of the perceived exertion of different categories of cyclists on a daily path within a long bicycle tour. We first propose an additive formula for calculating the perceived exertion of cyclists on component parts of a tour and then present the results of a survey designed to verify the accuracy of the model. In the second work, chapter 3, we describe an algorithmic procedure for transforming a traditional road graph into a topographical graph. To that end we use polyline data from the OpenStreetMap (OSM), elevation data from the U.S. Geological Survey, and a model of perceived exertion for bicyclists of different levels of expertise. Our topographical graph allows for the calculation of the perceived exertion over any sequence of road segments (a path) for bicyclists of different levels of expertise and serves as input for generating paths of minimal perceived exertion. In the final work, chapter 4, we describe a procedure for constructing bicycle routes of minimal perceived exertion for cyclists of different levels of expertise over a multi-day tour. Given a cyclists origin, destination, selected points of interest, and a level of cycling expertise, this procedure generates a multi-day bicycle tour as a collection of successive daily paths that begin and end at overnight accommodations. We demonstrate the implementation of this procedure on an example multi-day tour route in California and present the results of a survey designed to evaluate the daily paths constructed. In summation, this dissertation contributes a new metric of perceived exertion for bicycle riders, a new topographical graph, and a procedure for constructing multi-day bicycle tour routes of minimal perceived exertion for bicyclists of different levels of expertise.
76

Reading cycles : the culture of BMX freestyle

Nelson, Wade Gordon James. January 2006 (has links)
This dissertation draws from and contributes to many traditions within the (interdisciplinary) discipline of communication studies. Serving the two primary objectives of the examination of the figure of the BMX freestyle cycling Pro and the analysis of the role of the magazines within this particular culture or field in the construction and maintenance of this figure, this project brings together studies of cultural intermediaries, magazine history, advertising history and theory, subcultures, audiences, commodification, cultural industries, celebrity, stars and professional athletes. The culture of BMX freestyle cycling is an interesting and heretofore unexamined phenomenon, and a focused examination allows the exploration and investigation of larger questions within the discipline. As such, this dissertation provides an informed interpretation of the culture of BMX freestyle, allows the examination of a number of other issues concerning the mediation of cultural practices, and suggests a theory of the special-interest magazine, thus contributing substantively to various literatures. / Special-interest magazines are a part of a larger system and industries within which the ultimate goal is the sale of commodities. At the same time, they function as a site of credibility within a larger field, both conferring star status on particular individuals and approving particular commodities that are being offered to the readers. Special-interest magazines construct and sell audiences to advertisers, create star systems, propose candidates for stardom, help build image careers, contribute substantially to a "star currency" within the particular field, negotiate (i.e.; mediate) tensions between the advertisers, the stars, and the readers, help organize the time of a culture and work to infuse it with a sense of vitality through the punctual and ritualistic appearance of novel content, assist the consumer with their desires for commodities and stars by standing as catalogues of commodities (serving to educate newcomers in the protocol of the culture), provide new financial opportunities (such as the commodity form of the photo contingency), and in their complicity with the needs of those that provide their primary source of revenue, give more value to the advertising dollar in the construction of editorial content that could be seen as advertising.
77

Bike big data : how GPS route data collected from smartphones can benefit bicycle planning

Meyer, Joel Loren 04 December 2013 (has links)
In order to determine the most effective ways to increase ridership in their communities, bicycle planners require quality data on bicycling behavior. Traditional bicycle data collection methods, however, are limited by the large amount of time and expertise required to process and analyze the data, by their inability to provide information at the level of detail needed to understand the complexities of bicycling behavior, and by issues related to sampling bias and poor respondent trip recall. Fortunately, a relatively new method for collecting travel data has emerged that has the potential to provide higher quality and lower cost bicycle data to local planning agencies than has previously been possible with traditional data collection methods: the use of global positioning system (GPS) sensors in smartphones. Researchers at The University of Texas recently evaluated the usefulness of one such smartphone application - "CycleTracks" - to collect bicycle route data. Over 3,600 unique trips were collected from around 300 cyclists in Austin, Texas between May and October, 2011. While they found the CycleTracks app to be useful for collecting a large dataset, to this point there has been only limited analysis of the route data in terms of its usefulness in the planning field. This report will explore the ways in which GPS route data collected from smartphones can address some of the limitations of traditional data collection methods. Austin is used as a case study to show how the GPS route data can be used to plan for network connectivity, to identify barriers in the bicycle network, and to analyze cycling behavior before and after the installation of new facilities. The report finds that despite a number of limitations, smartphone-based GPS data collection has the potential to become an important part of local planning agencies' regular data collection efforts.
78

Aerodynamics of High Performance Bicycle Wheels

Moore, Jaclyn Kate January 2008 (has links)
This thesis presents the work undertaken to assess potential improvements in high performance bicycles. There are several wheel options available for elite riders to use in competition and this research has investigated the aerodynamic properties of different wheel type. The research has also developed CFD and FEA models of carbon fibre bicycle wheels to assist in the wheel improvements process. An accurate and repeatable experimental test rig was developed to measure the aerodynamic properties of bicycle wheels in the wind tunnel, namely translational drag, rotational drag and side force. Both disk wheels and spoked wheels were tested. It was found that disk wheels of different hub widths have different aerodynamic properties with the 53mm wide Zen disk wheel requiring the lowest total power of the wheels tested. There was little difference between the translational power requirements of the wheels but there was greater variation in the rotational power requirements. Compression spoked wheels of 3 and 5 spokes were found to require less power than wire spoked wheels. There was little difference between the total power requirements of the compression spoked wheels tested, with the differences at 50km/hr being less than the experimental uncertainty. The Zipp 808 wheel demonstrated considerably lower axial force than all other wheels at 10° yaw angle, confirming Zipp design intention to have optimum wheel performance between 0-20°. The Zen 3-spoke wheel showed the lowest axial drag and side force at yaw of the compression spoked wheels tested and had similar side force results to the Zipp 808. CFD models of the disk and 3-spoke wheel achieved good agreement with the experimental results in terms of translational drag. Rotational drag did not agree so well, most likely due to the turbulence model being designed for higher Reynolds number flows. A FE model of the disk wheel was validated with experimental testing. In order to simplify modelling, the FE model of the 3-spoke wheel did not include the hub, which led to a large discrepancy with experimental results for the particular loading scenario. The experimental rig and CFD models were used to develop aerodynamic improvements to the wheel and the FE models were used to identify the implication of geometric changes to the wheel structural integrity. These improvements are not reported in this thesis due to the results being commercially sensitive.
79

A COMPARISON OF VISUALISATION TECHNIQUES FOR A BICYCLE SIMULATOR

Cosimato, Pasquale January 2014 (has links)
In this project, the perception of distance and the degree of immersion in a game, with two different visualisation techniques, have been evaluated. A bicycle simulator was used, and the game has been tested in a non-immersive virtual reality, by projecting the game on a screen, and using an immersive virtual reality by Oculus Rift. The study provides a preliminary investigation that focuses on how humans can perceive the distance, an overview of the term immersion and how to quantify this component.Regarding the study of the perception of distance, to subjects who have tested the game has been asked their perceptions of distance with respect to a given object. The immersion was studied and evaluated using a questionnaire given to each subject.The results showed an underestimation of distance in both the visualisation of the game, precisely a greater underestimation respect to real distance when the screen was used was found.The degree of immersion did not detect large differences between the two visualisation techniques.
80

A ward level investigation of patterns of cycling to work in metropolitan areas

Ashley, C. A. January 1988 (has links)
No description available.

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