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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

Creating a culture of safety : Austin, Texas

Bennett, Lauren Dayle 08 August 2012 (has links)
Pedestrian and cyclist collisions with motor vehicles are a growing problem in the United States and in particular Austin, Texas. These collisions cause unnecessary loss of life and injury. This research explores strategies in the realms of engineering, education and enforcement from three leading cities for pedestrian and cyclist safety. Based on the analysis, I have identified possible strategies for use in Austin, Texas to prevent these collision types. I also offer a conceptual model that can be used as a framework for organizing and thinking about the various components involved in preventing pedestrian and cyclist collisions with motor vehicles. / text
2

Bicycling in Hamilton: Challenges Associated with Bicycling and Cyclists' Subjective Identities

van Miltenburg, Benita January 2016 (has links)
In order to adequately design for and promote safe and regular use of the bicycle as a form of active transportation, researchers and policy-makers alike would benefit from the input of practiced bicyclists. These lay experts possess unique experiential knowledge of local routes, gaps in the network and the degree of comfort afforded by different types of infrastructure. Furthermore, these individuals are adept at commenting on subjectively valuable aspects of bicycling, which may assist in informing promotion and marketing of this activity. This research draws on the knowledge of lay experts who regularly bicycle in Hamilton, Ontario. The objectives of this research were to identify and understand the challenges associated with bicycling in Hamilton, and to explore the subjective identities of Hamilton’s cyclists. A thematic analysis of 10 semi-structured interviews was conducted and the following themes were identified and explored: an array of physical, structural and social deterrents to bicycling exist in Hamilton; and the identities of Hamilton’s cyclists are complex, locally rooted and multidimensional in nature. Using a critical lens, with the help of the Social Ecological Model of Health and Identity Theory, this study draws the following conclusions: cyclists are well-equipped to critically evaluate the urban spaces through which they travel; cyclists may play an important role in encouraging non-users to take up bicycling; and cyclists and auto drivers may benefit from collaborating over mutually beneficial goals. Furthermore, while many individuals who ride bicycles do identify themselves as “cyclists” this terminology can be contentious and the identity is heavily rooted in cyclists’ local context. Although this identity is primarily experienced individually, a sense of community does exist; and the identity often spans beyond the simple action of riding a bicycle. / Thesis / Master of Arts (MA) / In order to adequately design for and promote safe and regular use of the bicycle as a form of active transportation, researchers and policy-makers alike would benefit from the input of practiced bicyclists. These lay experts possess unique experiential knowledge of local routes, gaps in the network and the degree of comfort afforded by different types of infrastructure. Furthermore, these individuals are adept at commenting on subjectively valuable aspects of bicycling, which may assist in informing promotion and marketing of this activity. This research draws on the knowledge of lay experts who regularly bicycle in Hamilton, Ontario. The objectives of this research were to identify and understand the challenges associated with bicycling in Hamilton, and to explore the subjective identities of Hamilton’s cyclists. An analysis of 10 semi-structured interviews was conducted and the following themes were identified and explored: an array of physical, structural and social deterrents to bicycling exist in Hamilton; and the identities of Hamilton’s cyclists are complex, locally rooted and multidimensional in nature. This research emphasizes the contributions bicyclists have to offer social science literature and highlights the need for continual input and engagement with everyday bicycle users. This ongoing communication is important to adequately support and encourage regular and new bicycle users in practicing this healthy and sustainable means of transportation.
3

Bezpečnost cyklisty předjížděného motorovým vozidlem / The Safety of a Cyclist passed by car

Pavlík, Radim January 2015 (has links)
Title The Safety of a Cyclist passed by car Objectives: The aim of this thesis is to identify by field research whether drivers abide by the distance of at least 1 m when passing cyclists or not. Furthermore to find out from the results of a survey whether previous experience of the drivers as a cyclist influences their behavior. Methods: As for the methods used in this study, field research and public survey had been conducted. Results: Drivers are respecting the passing distance at least 1 meter. The average passing distance, which was foundet out from the results of the survey, was 153 centimeters by the speed of 50 km/h. In conclusion of this thesis is that cyclists and non-cyclists have the same opinion of the passing distance between the cyclist and the passing car. Keywords: Cyclist, passing, safety, accident.
4

Cyclist Behavior to Avoid Vehicle Collisions Using Drive Recorder Videos

Zhao, Yuqing, Mizuno, Koji 02 January 2023 (has links)
Since bicycles travel at high speeds and are frequently involved in traffic accidents, reducing bicycle fatalities and injuries is one of the most important issues in traffic safety. In car-to-cyclist collisions, the perpendicular configuration occupies the largest proportion of these collisions. Driver responses in lateral intrusions of cyclists at intersections have been examined [1,2], focusing on the drivers' braking reaction time and the time-to-collisions (TTC). Cyclist behavior can also have a significant intluence on car-to-cyclist collision occurrence. Cyclist bebavior has been investigated in naturalistic conditions and using in-depth accident data. In addition, the videos of drive recorders provide useful information on the cyclist behaviors [3]. This study investigated cyclist behavior with the drive recorder of cars in near-miss incidents and collisions. [From: Introduction]
5

Freestyle BMX a letní olympijské hry / Freestyle BMX and olympic games

Čermák, Daniel January 2018 (has links)
Tittle: Freestyle BMX and Summer Olympic Games Objectives: The main aim of this thesis is the analysis process of Freestyle BMX acceptance to the Tokyo 2020 Summer Olympics with evalution. In addition, this thesis defines the historical movement of the Freestyle BMX candacy and evaluate the conditions (criteria) setted by the International Olympic Committee for the adoption of new sports into the Olympic Games program. Methods: This thesis is a theoretical work that has a descriptive and analytical character so the main method is an analysis and study of documents, literature and web sources. The information was analyzed and comprehensively processed. Results: Results indicate that Freestyle BMX didn't satisfy all the criteria for acceptance of a new sport into the Olympic Games program. Freestyle BMX should not be accepted according to the criteria set into the Olympic Games program. Freestyle BMX was accepted on the basis of other facts according to this information. Probably this has been achieved on the basis of an evaluation of the popularity sport. Keywords: Sport, Cyclist, Cyclist discipline, Freestyle BMX, Olympics, Summer Olympic Games, Tokyo 2020
6

L’utilisation des mesures d’exposition dans les études sur la sécurité cycliste : revue de littérature quasi-systématique et démonstration de leur effet sur les résultats d’analyse du risque

Vasil, Pier-Alexandre 12 1900 (has links)
La littérature sur la sécurité cycliste présente des résultats parfois contradictoires, car l’utilisation des mesures d’exposition est peu fréquente. Ce mémoire de maîtrise cherche à décrire les mesures d’exposition et la méthodologie associée dans le calcul du risque de blessures chez les cyclistes dans le contexte québécois, ainsi que montrer l’impact de leur utilisation. D’abord une revue narrative quasi-systématique sur les mesures d’exposition aidant à préciser leur utilisation dans le calcul du taux d’incidence de blessures chez les cyclistes est effectuée en incluant les concepts de sécurité, du vélo et des mesures d’exposition. Puis, des mesures d’exposition sont utilisées pour comparer les taux d’incidence de blessures à vélo obtenus dans deux régions du Québec, soit l’Outaouais et Laval, qui se distinguent considérablement au regard de la proportion de port du casque chez les cyclistes et au regard de la quantité d’infrastructures cyclables totales disponibles. Des taux d’incidence des blessures à la tête et blessures totales chez les cyclistes sont calculés pour ces deux régions en utilisant au dénominateur une mesure de fréquence populationnelle et des mesures d’exposition (distance, déplacements, nombre de cyclistes). Les régions sont comparées entre elles en calculant les ratios de taux d’incidence. Les ratios de taux d’incidence utilisant les mesures de fréquence populationnelle montrent peu de différence pour les blessures chez les cyclistes entre les deux régions, alors que les ratios calculés avec les trois mesures d’exposition montrent la région de Laval comme étant plus à risque. Ceci montre l’impact de l’utilisation des mesures d’exposition dans les études de sécurité cycliste. / Cyclists’ safety literature often presents contradictory findings. Infrequent use of exposure in those studies is one reason why. This work aims to describe how to use exposure variables to calculate cyclists’ injury incidence rate in the province of Quebec. A quasi-systematic narrative review on exposure variable in the context of safety of bicyclists was conducted to guide their use. Then, exposure variables were used to compare the incidence rates of head and total injuries between the regions of Outaouais and Laval. These two regions were chosen because they differ in helmet usage and quantity of cycling infrastructures. Incidence rates for head and total injuries were calculated for both regions by controlling population frequency and three exposure variables (distance, trips and number of cyclists). Both regions were compared with incidence rate ratios. The incidence rate ratios using population frequency showed little to no difference in safety between both regions, while those using exposure variables showed that Laval presented greater risks for cyclists. These results show the importance of using exposure in safety studies for cyclists.
7

Cyclists' experiences in urban longitudinal traffic scenarios and their requirements for designing interactions with highly automated vehicles

Fritz, Nicole, Korthauer, Andreas, Bengler, Klaus 19 December 2022 (has links)
As cycling becomes more popular and automated driving is on the rise, it can be assumed that in the city of the future highly automated vehicles (HA Vs) and cyclists will share the same roads. Yet only little is known about how cyclists announce their maneuvers to motorized vehicles or how they communicate and interact with them. Knowledge on these aspects is currently missing to guide the design of cyclist-HA V interactions. Situations where a cyclist rides upfront a vehicle, will be especially challenging for HA Vs, such as when a cyclist (A) avoids an obstacle on the road section ahead, (B) merges onto the road from an ending cycling path, or (C) leaves the road turning into a driveway {see Figure 1) [1 ]. Based on the cyclist's intention, the HA V will have to pass or keep following with only limited options to communicate to the cyclist ahead. Design solutions derived from the well-studied field of pedestrian-HA V interactions cannot simply be transferred to the here considered cyclist-HA V interactions, since in past research successful design concepts for pedestrians were not beneficial for cyclists [2]. Hence, it is vital to investigate the behavior and experiences of cyclists in more detail and to explore possible design solutions for HA V interaction behavior in these situations. With this study we aim to get more insights into the subjective experience of cyclists travelling in longitudinal traffic, especially during cyclist-vehicle interactions, as well as to derive cyclists' requirements to design safe and desirable cyclist-HA V interactions.
8

Acute Postactivation Potentiation Using Isometric and Dynamic Mid-Thigh Clean Pulls in Trained Weightlifters, Powerlifters, and Sprint Cyclist

Kavanaugh, Ashley A., Israetel, Michael A, Sato, Kimitake, Lamont, Hugh S., Stone, Michael H. 01 July 2012 (has links)
Countermovement vertical jump (CMVJ) performance may be acutely facilitated via potentiation (PAP) due to central and peripheral factors. PURPOSE: To investigate the effects of two methods of PAP in trained weightlifters (n=16); group 1: stronger (n=7) and group 2: weaker (n=9) upon unweighted countermovement jumps (CMVJs) over a 15 minute time period. METHODS: A series of maximal unweighted CMVJs were performed prior to, then at, 30, 60, 120, 180, 300, 480, 660, 780, and 900 seconds following two conditions: isometric mid-thigh clean pulls (C1) and dynamic mid-thigh clean pulls (C2). Dependent variables included, jump height (JH, cm), peak power (PP, W), peak velocity (PV, m·s-1), and peak force (PF, N). RESULTS: A series of repeated measures ANOVA: conditions (2); time points (10); groups (2) were performed on JH, PP, PV, and PF (p>.05). Significant main effects for JH existed by condition (C1>C2) (p=.001, ES=.571, 1-β=.979, mean diff=.053cm), group (G1>G2) (p=.018, ES=.339, 1-β=.702, mean diff=.053), and time (60s>900s, 120s>900s, 180s>900s) (p=.014, ES=.148, 1-β=.910).Within subjects main effects for JH were seen for the stronger group for JH by condition (C1>C2) (p=.055, ES=.757, 1-β=.947, mean diff=.053cm), and weaker group by condition (C1>C2) (p=.025, ES=.487, 1-β=.676, mean diff=.054cm). Significant main effects existed for PP by condition (C1>C2) (p=.000, ES=.631, 1-β=.995, mean diff=427.9W), group (G1>G2) (p=.008, ES=.405, 1-β=.819, mean diff=1660.1W), and time (60s>480s, 60s>660s, 60s>780s, 60s>900s>120s>900s, 180s>480s, 180s>660s, 180s>780s) (p=.000, ES=.355, 1-β=1.00, mean diff=240.1W ).Within subjects main effects for PP were seen for the stronger group for condition (C1>C2) (p=.055, ES=.761, 1-β=.951, mean diff=516.8W), and time (120s>900s) (p=.000, ES=.471,1-β=.999, mean diff=319.5W). In the weaker group; significant main effects by condition (C1>C2) (p=.025, ES=.485, 1-β=.672, mean diff=339.1W) and time (120s>900s, 180s>480s, 180s>900s, 300s>900s) (p=.003, ES=.281, 1-β=.963, mean diff=319.5W). Significant main effects were seen for jump PV by condition (C1>C2) (p=.001, ES=.536,1-β=.962, mean diff=.177 m·s-1), group (G1>G2) (p=.022, ES=.320, 1-β=.665, mean diff=.298m/s) and by time (60s>900s, 120s>900s, 180s>900s) (p=.016, ES=.145, 1-β=.904). Within subjects main effects for jump PV in the stronger group by condition (C1>C2) (p=.007, ES=.727, 1-β=.911, mean diff=.165m/s), and time (120s>900s) (p=.036, ES=.269, 1-β=.840, mean diff=.073 m·s-1). In the weaker group there were significant main effects for jump PV by condition (C1>C2) (p=.028, ES=.474, 1-β=.654, mean diff=.188 m·s-1). A significant main effect for jump PF by group (G1>G2) (p=.014, ES=.363, 1-β=.747, mean diff=647.0N) and time (60s>baseline) (p=.05, ES=.122, 1-β=.824, mean diff=71.0N) was seen. Within subjects, a significant main effect for jump PF in the weaker group by time (60s>780s) (p=.012, ES=.247, 1-β=.919). There were no significant interactions for any of the dependent variables (p >.05). CONCLUSION: Isometric mid-thigh clean pulls appear to have a greater potentiating effect than dynamic mid-thigh pulls on PP and PV during subsequent CMVJ0’s, and stronger weightlifters tend to have a more favorable response to both conditions. PRACTICAL APPLICATION: Whole-body isometric movements may be a more effective at eliciting a potentiation response than dynamic movements in strength and power athletes.
9

Numerical Accident Reconstructions : A Biomechanical Tool to Understand and Prevent Head Injuries

Fahlstedt, Madelen January 2015 (has links)
Traumatic brain injuries (TBIs) are a major health and socioeconomic problem throughout the world, with an estimated 10 million deaths and instances of hospitalization annually. Numerical methods such as finite element (FE) methods can be used to study head injuries and optimize the protection, which can lead to a decrease in the number of injuries. The FE head models were initially evaluated for biofidelity by comparing with donated corpses experiments. However, there are some limitations in experiments of corpses, including material degradation after death. One feasible alternative to evaluating head models with living human tissue is to use reconstruction of real accidents. However, the process of accident reconstruction entails some uncertainties since it is not a controlled experiment. Therefore, a deeper understanding of the accident reconstruction process is needed in order to be able to improve the FE human models. Thus, the aim of this thesis was to evaluate and further develop more advanced strategies for accident reconstructions involving head injuries. A FE head model was used to study head injuries in accidents. Existing bicycle accident data was used, as were hypothetical accident situations for cyclists and pedestrians. A FE bicycle helmet model having different designs was developed to study the protective effect. An objective method was developed based on the Overlap Index (OI) and Location Index (LI) to facilitate the comparison of FE model responses with injuries visible in medical images. Three bicycle accident reconstructions were performed and the proposed method evaluated. The method showed to have potential to be an objective method to compare FE model response with medical images and could be a step towards improving the evaluation of results from injury reconstructions. The simulations demonstrated the protective effect of a bicycle helmet. A decrease was seen in the injurious effect on both the brain tissue and the skull. However, the results also showed that the brain tissue strain could be further decreased by modifying the helmet design. Two different numerical pedestrian models were compared to evaluate whether the more time-efficient rigid body model could be used, instead of a FE pedestrian model, to roughly determine the initial conditions as an accident reconstruction involves some uncertainties. The difference, in terms of the head impact location, rotation and velocity, attributable to the two models was in the same range as differences due to uncertainties in some of the initial parameters, such as vehicle impact velocity. / <p>QC 20150414</p>
10

Rörlighet i ländryggen, sittposition och förekomst av ländryggssmärta hos landsvägscyklister.

Djurback, Ingrid January 2018 (has links)
Bakgrund: Ländryggsmärta orsakad av överbelastning är vanligt inom cykelidrotten med en prevalens mellan 15 % -60 % hos landsvägscyklister på motions- och elitnivå. Vid sittande förändras ryggradens kurvatur vilket gör att belastningen förändras och det ger obalanser och större risk för smärta och skada än vid stående och gående. Sittpositionen på cykeln kan anpassas genom justering av cykeln, även kallad bike fit. Det finns få vetenskapliga studier hur denna anpassning ska ske för att undvika ryggsmärta. Syfte: Syftet med studien var att undersöka hur strukturer i ländryggen och säte/ben påverkar sittposition och förekomsten av ländryggssmärta vid landsvägscykling. Metod: Totalt 33 deltagare analyserades för hamstringslängd, total lumbal flexion samt sittposition på cykeln. Deltagarna tillfrågades angående erfarenheter av ländryggssmärta vid cykling. Resultat: Studien kunde påvisa en signifikant korrelation (r=0,57, P= 0,00082) mellan sittposition på cykeln samt total lumbal flexion. Hamstringslängd eller lumbal flexion på cykel visade sig ej korrelera med ländryggssmärta på cykel. Ingen skillnad förelåg mellan de cyklister som rapporterat ländryggssmärta eller ej gällande total lumbal flexionsrörlighet, lumbal flexion på cykeln eller hamstringslängd visades. Konklusion: Rörlighet i ländryggen och position på cykel verkar inte ensamt kunna förklara förekomst av cykelrelaterad ländryggssmärta. Hamstringslängden tycks inte påverka sittposition eller ländryggssmärta vid cykling.

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