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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.
81

Challenges to implementing cyclist counting systems on rural roads

Lopez, Griselda, Moll, Sara, Vacalebri, Francisco, Garcia, Alfredo 03 January 2023 (has links)
In Spain, the presence of sport and recreational cyclists on rural roads has increased notably in recent years. In fact, the number offederation licences reached 75,638 cyclists and 3,634 cycling clubs in 2020. As the number of cyclists on these roads has increased, so has the number of accidents. Despite regulations, information campaigns and measures t.aken by the Spanish Directorate-General for Traffic in recent years, the number of crashes involving cyclists in rural environments remains plateaued at near 50 cyclist fatalities per year. Most Spanish rural roads do not have specifi.c infrastructure for cyclists - e.g. cycle lanes. Theo. cyclists and drivers share the road and interact; being the overtaking manoeuvre one of the most dangerous interactions. These interactions imply risk of rear-end and side-on collisions with cyclists and head-on collisions with oncoming vehicles during the overtaking manoeuvre. Since traffic crashes and risk exposure are highly correlated, every interaction between cyclists and/or with motorised vehicles increases the likelihood of a traffic crash. Consequently, to properly assess road safety on rural roads, an adequate estimation of cycle volume is needed. On the other band, cyclists may ride in groups in different confi.gurations (in-line or two-abreast), which can also affect the traftic operation by creating queues and increasing the delay time of m.otorised vehicles. Therefore, determining the volume of cyclists on a rural road segment is a necessary challenge in order to integrate them into safety and traffic operation analyses. Cycle volume is of great interest for many applications. In fact, knowing the spatial and temporal distribution of cycle volume across a road network. can help engineers to plan and manage these roads, improving road safety and traffic operation. Furthermore, knowing cycle volume can also help motorised drivers. Waming drivers about the presence of cycl:ists before reaching them improves road safety, as drivers can adapt their behaviour to interact with cyclists more safely. One tool to inform drivers of the presence of cyclists in this environment is the use of vertical signs. These systems have evolved in recent years, from simple static signs (infomring ofthe possible presence of cyclists), to the implementation of active and intelligent signs. Active or dyn.amic signs alert drivers about the presence of cyclists in real time, raising their level of attention. This is extremely important, since driver inattention or speeding was present in half of crashes involving cyclists on Spanish rural roads. There are many technologies for cyclist detection. Most of them have been used in urban areas, where cyclists have specific facilities. However, rural roads present particu1arities duc to the type of infrastructure, users, and how they interact. For this reason, the main objective of this study is to analyse what challenges existing counting systems must overcome in order to be effective on rural environment. The analysis will consider the particular characteristics of the phenomenon tobe detected, both the characteristics ofthe cyclists themselves and of the road.
82

Understanding the interaction between cyclists and automated vehicles: Results from a cycling simulator study

Mohammadi, Ali, Piccinini, Giulio B., Dozza, Marco 19 December 2022 (has links)
Cycling as an active mode of transport is increasing across all Europe [1]. Multiple benefits are coming from cycling both for the single user and the society as a whole. With increasing cycling, we expect more conflicts to happen between cyclists and vehicles, as it is also shown by the increasing cyclists' share of fatalities, contrary to the passenger cars' share [2]. Understanding cyclists' behavioral patterns can help automated vehicles (AVs) to predict cyclist's behavior, and then behave safely and comfortably when they encounter them. As a result, developing reliable predictive models of cyclist behavior will help AVs to interact safely with cyclists.
83

Personlighet hos ultralöpare och cyklister : En jämförande studie av the Big Five hos deltagare i Ultravasan och Cykelvasan 2015 / Personality in ultra runners and cyclists : A comparative study of the Big Five among participants in Ultravasan and Cykelvasan

Bröms, Emelie, Hultenmo, Andreas January 2016 (has links)
Allt fler människor deltar i lopp som sträcker sig över långa distanser. Denna studies syftevar att undersöka om dessa människors personligheter skiljer sig åt beroende på vilkengren de deltar i, och i så fall på vilket sätt. Med utgångspunkt i femfaktorteorin (Big Five)och med hjälp av ett självskattningsformulär, Revised NEO Personality Inventory, undersöktesoch jämfördes 214 löpare i Ultravasan 2015 och 145 cyklister i Cykelvasan 2015.Frågeställningen som föranledde arbetet var ifall löparnas personlighet skiljer sig från cyklisternas.Resultaten visade att löpare har en högre grad öppenhet i jämförelse med cyklisterna.Löparna hade även en lägre grad av extraversion i förhållande till cyklisterna,en skillnad som var statistiskt signifikant. Generellt sett visade resultaten små skillnadermellan löpare och cyklister. / More people than ever participate in long distance races and the purpose of this study wasto investigate the personality of these individuals. We had 214 Ultravasan runners and145 Cykelvasan cyclists complete the Revised NEO Personality Inventory test, to assesstheir personality based on the Big Five. The main question was whether the personality ofthe runners would differ from the cyclists’.Results showed that runners scored higher on openness compared to the cyclists.Furthermore, runners were significantly less extrovert than the cyclists. Generally however,the results showed minor differences in personality between the two groups.
84

Mobilitätsverhalten potentieller Radfahrer in Dresden

Manteufel, Rico 01 October 2015 (has links) (PDF)
Before the German reunification, Dresden was a city of motorized traffic and cyclist were rare. But in the 90's began a change of transport policy and cycling became more important. This Master Thesis wants to show the current standing of cycling in Dresden. Thats why the results of the "SrV"-study should be analysed with regard to potential cyclists and their journeys. As methods were used a descriptive analysis and the linear discriminant analysis, both used at a personal and journey-specific level of data. As a result, Dresden have to do much more to become a good "cycling-city", so the bike-level wasn't really high in the year 2013. Instead the car is still the mostly used transport vehicle and the proportion in the Modal-Split is only slowly sinking. But this study shows typical characteritics of cyclists and cycling journays of Dresden, so there is a basis to get more people involved to cycle and become a more eco-friendly city.
85

Um modelo para dimensionamento de calçadas considerando o nível de satisfação do pedestre / A model for sidewalk sizing considering the level of satisfaction of the pedestrian

Carvalho, Marcus Vinicius Guerra Seraphico de Assis 15 March 2006 (has links)
Neste trabalho é apresentado um modelo para dimensionamento de calçadas considerando o nível de satisfação do pedestre. O modelo foi desenvolvido com base em pesquisa conduzida na cidade de Boa Vista, Roraima. Apesar de a cidade apresentar uma demanda razoável de viagens realizadas por bicicletas, não possui uma infra-estrutura adequada para ciclistas, razão porque uma parte considerável dos ciclistas trafega pela calçada. Por este motivo, foi incluído no modelo proposto o fluxo total de ciclistas na via, uma variável que não é mencionada em nenhum outro método de avaliação do nível de serviço de calçadas. Para desenvolver o modelo foram utilizadas as técnicas de árvore de decisão e de regressão robusta MM, contidas no programa S-Plus 6.1. A partir da comparação com outros trabalhos analisados, será mostrado que, desconsiderando o fluxo de ciclistas, o modelo elaborado é compatível com outros desenvolvidos em várias partes do mundo. Devido a limitações da amostragem e caráter local da área estudada, não há elementos suficientes para se afirmar que o modelo ora proposto seja amplamente utilizável quando se considera o fluxo de ciclistas. Porém, mostra-se que, além de permitir avaliar o nível de serviço de calçadas, o modelo pode ser usado no dimensionamento de tais infra-estruturas, sendo útil, portanto, no planejamento urbano / This thesis presents a model for determining sidewalk width taking into account the level of pedestrian satisfaction. The model was developed using the data collected in the city of Boa Vista, State of Roraima, Brazil. Although cycling demand in the city is not low, Boa Vista does not have any facilities for cyclists. As a consequence, a part of them rides on the sidewalk. Taking this reason into account, the total flow of cyclists on the street was included in the proposed model, a variable not mentioned in other methods for evaluating pedestrian level of service on sidewalks. Decision tree and MM robust regression techniques available in S-Plus 6.1 software were used to develop the model. From a comparison with other works, it is shown that, without the cyclists flow, the proposed model provides results that are similar to those of other authors. Due to sample size and geographic limitations of this research, there are still not enough elements to affirm that the model is widely applicable when the cyclists flow on the sidewalk. However, the present work shows that besides the capability to evaluate the sidewalk level of service, the model can also be used for sidewalk sizing and thus, it is a useful tool on urban planning
86

Um modelo para dimensionamento de calçadas considerando o nível de satisfação do pedestre / A model for sidewalk sizing considering the level of satisfaction of the pedestrian

Marcus Vinicius Guerra Seraphico de Assis Carvalho 15 March 2006 (has links)
Neste trabalho é apresentado um modelo para dimensionamento de calçadas considerando o nível de satisfação do pedestre. O modelo foi desenvolvido com base em pesquisa conduzida na cidade de Boa Vista, Roraima. Apesar de a cidade apresentar uma demanda razoável de viagens realizadas por bicicletas, não possui uma infra-estrutura adequada para ciclistas, razão porque uma parte considerável dos ciclistas trafega pela calçada. Por este motivo, foi incluído no modelo proposto o fluxo total de ciclistas na via, uma variável que não é mencionada em nenhum outro método de avaliação do nível de serviço de calçadas. Para desenvolver o modelo foram utilizadas as técnicas de árvore de decisão e de regressão robusta MM, contidas no programa S-Plus 6.1. A partir da comparação com outros trabalhos analisados, será mostrado que, desconsiderando o fluxo de ciclistas, o modelo elaborado é compatível com outros desenvolvidos em várias partes do mundo. Devido a limitações da amostragem e caráter local da área estudada, não há elementos suficientes para se afirmar que o modelo ora proposto seja amplamente utilizável quando se considera o fluxo de ciclistas. Porém, mostra-se que, além de permitir avaliar o nível de serviço de calçadas, o modelo pode ser usado no dimensionamento de tais infra-estruturas, sendo útil, portanto, no planejamento urbano / This thesis presents a model for determining sidewalk width taking into account the level of pedestrian satisfaction. The model was developed using the data collected in the city of Boa Vista, State of Roraima, Brazil. Although cycling demand in the city is not low, Boa Vista does not have any facilities for cyclists. As a consequence, a part of them rides on the sidewalk. Taking this reason into account, the total flow of cyclists on the street was included in the proposed model, a variable not mentioned in other methods for evaluating pedestrian level of service on sidewalks. Decision tree and MM robust regression techniques available in S-Plus 6.1 software were used to develop the model. From a comparison with other works, it is shown that, without the cyclists flow, the proposed model provides results that are similar to those of other authors. Due to sample size and geographic limitations of this research, there are still not enough elements to affirm that the model is widely applicable when the cyclists flow on the sidewalk. However, the present work shows that besides the capability to evaluate the sidewalk level of service, the model can also be used for sidewalk sizing and thus, it is a useful tool on urban planning
87

Bicyclists' Uptake of Traffic-Related Air Pollution: Effects of the Urban Transportation System

Bigazzi, Alexander Y. 27 October 2014 (has links)
While bicyclists and other active travelers obtain health benefits from increased physical activity, they also risk uptake of traffic-related air pollution. But pollution uptake by urban bicyclists is not well understood due to a lack of direct measurements and insufficient analysis of the determinants of exposure and ventilation (breathing). This knowledge gap impedes pollution-conscious transportation planning, design, and health impact assessment. The research presented in this dissertation generates new connections between transportation system characteristics and pollution uptake by bicyclists. The primary research questions are: 1) how do urban bicyclists' intake and uptake of air pollution vary with roadway and travel characteristics and 2) to what extent can transportation-related strategies reduce uptake. Breath biomarkers are used to measure absorbed doses of volatile organic compounds (VOCs). This research is the first application of breath biomarkers to travelers and the first uptake measurements of any pollutant to include roadway-level covariates. Novel methods to collect and integrate bicycle, rider, traffic, and environmental data are also introduced. Bicyclist exposure concentrations, exhaled breath concentrations, respiratory physiology, and travel characteristics were collected on a wide range of facilities in Portland, Oregon. High-resolution trajectory and pollution data were then integrated with roadway and traffic data. Models of exposure, ventilation, and uptake of VOCs were estimated from the on-road data. Important new quantifications in the models include the effects of average daily traffic (ADT) on multi-pollutant exposure, the lagged effect of on-road workload on ventilation, and the effects of exposure and ventilation on absorbed VOCs. Estimated models are applied to situations of interest to travelers and transportation professionals. Sample applications include the inhalation dose effects of road grade, cruising speed choice, stops, and detouring to parallel low-traffic facilities. In addition, dose-minimizing routing behavior is compared with revealed routing preferences in the literature. Finally, findings from this research and the literature are distilled so that they can be incorporated into bicycle network design guidelines.
88

Travel Mode Choice Framework Incorporating Realistic Bike and Walk Routes

Broach, Joseph 26 February 2016 (has links)
For a number of reasons--congestion, public health, greenhouse gas emissions, energy use, demographic shifts, and community livability to name a few--the importance of walking and bicycling as transportation options will only continue to increase. Currently, policy interest and infrastructure funding for nonmotorized modes far outstrip our ability to model bike and walk travel. To ensure scarce resources are used most effectively, accurate models sensitive to key policy variables are needed to support long-range planning and project evaluation, and to continue adding to our growing understanding of key factors driving walk and bike behavior. This research attempts to synthesize and advance the state of the art in trip-based, nonmotorized mode choice modeling. Over the past fifteen years, efforts to model the decision to walk or bike on a given trip have been hampered by the lack of a comprehensive behavioral framework and inconsistency in measurement scales and model specification. This project develops a mode choice behavioral framework that acknowledges the importance of attributes along the specific walk and bike routes that travelers are likely to consider, in addition to more traditional area-based measures of travel environments. The proposed framework is applied to a revealed preference, GPS-based travel dataset collected from 2010-2013 in Portland, Oregon. Measurement of nonmotorized trip distance, built environment, tour-level variables, and attitudinal attributes as well as mode availability are explicitly addressed. Route and mode choice models are specified using discrete choice techniques, and predicted walking and bicycling routes are tested as inputs to various mode choice models. Results suggest strong potential for predicted route measures to enhance walk and bicycle mode choice modeling. Findings also support the specific notion that bicycle and pedestrian infrastructure contribute not only to route choice but also to the choice of whether to bike or walk. For decisions to bicycle, availability of low-traffic routes may be particularly important to women. Model results further indicate that land use and built environments around trip ends and a person’s home still have important effects on nonmotorized travel when controlling for route quality. Both route and area travel environment impacts are mostly robust to the inclusion of residential self-selection variables, consistent with the idea that built environment differences matter even for households that choose to live in a walkable or bikeable neighborhood. The combination of area and route-based built environment measures alongside trip context, sociodemographic, and attitudinal attributes provides a new perspective on nonmotorized travel behavior relevant to both policy and practice.
89

Att färdas i symbios : ett gång -och cykelstråk anpassat efter trafikanternas rörelsemönster och behov

Södergren, Natasha January 2011 (has links)
The aim of this paper is to examine the layout of public spaces and its effect on human behavior with focus on the relation between pedestrians and cyclists movement patterns in a specific path. The study emanates from the security aspect of pedestrians and cyclists, and builds upon previous theories and empirical studies about perception, security, information design, environmental psychology and behavior. The result shows that individual behavior and movement pattern differs with age, purpose, physical- and other conditions, and layout of the surroundings. A design proposal for improved layout of a path and a node between different oncoming paths has been developed to aid the users’ needs, where a separation of walkways and bike lanes forms zones of security for the purpose of better orientation and a better flow between the users. / Syftet med arbetet är att undersöka det offentliga rummets utformning och dess påverkan på det mänskliga beteendet med fokus på att studera relationen mellan gång-och cykeltrafikanternas rörelsemönster i ett specifikt gång-och cykelstråk. Studien utgår från trygghetsaspekten mellan gång- och cykeltrafikanter och bygger på samtida forskning om trafikanternas beteenden, teorier om perception, informationsdesign, stadsplanering, miljöpsykologi, samt empiriska studier. Resultatet visar att trafikanternas beteende och rörelsemönster skiljer sig beroende på ålder, mål med färden, fysiskt tillstånd och de egna förutsättningarna, samt omgivningen. Ett gestaltningsförslag på en förbättrad utformning av ett gång-och cykelstråk och en knutpunkt mellan olika mötande stråk har tagits fram utifrån trafikanternas behov, där en separering av gång -och cykelbana bildar olika trygghetszoner som ska bidra till en bättre orientering och ett bättre flöde mellan trafikanterna.
90

Nehodovost cyklistů / Accident Frequency of Cyclists

TOMANDL, Petr January 2007 (has links)
In compliance with a worldwide there is a growing interest in cycling tourism even in the Czech Republic Cycling is getting modern and is starting to be an inseparable part of lifestyle. Today{\crq}s situation brings positive and negative consequences. The most important negative one is growing accident rate that is connected with considerable economic losses and mainly with casualties. The aim of this work was to collect dates concerning all accidents with bikers attendance in the region of České Budějovice from April 2006 to October 2006 and consequently to analyze cyclist{\crq}s injuries. By this research was found out that in corpus 60% of accidents with cyclists attendance result in head injury of the cyclist. This injury forms 35% of all cyclists{\crq} injuries in corpus. The second most frequent injury is a leg injury with 40%.

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