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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

Exploring the Determinants of Vulnerable Road Users' Crash Severity in State Roads

Caviedes Cómbita, Àlvaro Alfonso 08 December 2017 (has links)
Pedestrians and bicyclists are the most vulnerable road users and suffer the most severe consequences when crashes take place. An extensive literature is available for crash severity in terms of driver safety, but fewer studies have explored non-motorized users' crash severity. Furthermore, most research efforts have examined pedestrian and bicyclist crash severity in urban areas. This study focuses on state roads (mostly outside major urban areas) and aims to identify contributing risk factors of fatal and severe crashes involving pedestrians and bicyclists in state roads. Two ordinal regression models were developed (one for pedestrian and the other for bicyclist crashes) to examine crash severity risk factors. Additional models were developed to investigate road and traffic characteristics that could increase the likelihood of fatal crashes. In the model for pedestrian crash severity risk factors such as age, vehicle type and movement, light conditions, road classification, traffic control device, posted speed limit, location of the pedestrian and wet road surface during clear weather conditions are statistically significant. The bicyclist crash severity model indicates that age, crash location, vehicle movement and alcohol intoxication during dark conditions are statistically significant. In terms of road characteristics and traffic conditions, the models suggested risk factors such as arterials, light conditions, posted speed limit, roadways, and high heavy vehicle volume, increased the odds of a crash being fatal. The results seem to suggest that besides improvements in roadway characteristics, additional countermeasures to reduce crash severity for vulnerable users should include separation of vulnerable users from traffic, educational campaigns, more strict control of alcohol intoxicated drivers, and protection strategies of senior pedestrians.
12

The epidemiology of motor vehicle collisions involving pedestrians in eThekwini Municipality, 2001-2006.

Hobday, Michelle Bridget. January 2009 (has links)
Introduction Road traffic collisions in developing countries contribute towards the greatest burden of disabilities and fatalities globally. Concern has arisen about the high proportion of pedestrians involved in collisions in South Africa. Aim This study describes the epidemiology of motor vehicle collisions involving pedestrians in eThekwini Municipality from 2001 to 2006, aiming to identify opportunities for prevention and informing policy. Methods An analytic cross-sectional study design was used. Data was obtained from the eThekwini Transport Authority database (police accident reports), and the Nationallnjury Mortality Surveillance System (mortuary reports). Exposure variables included pedestrian and drivers' demographics and collision environment. Death and injury were the outcome variables measured. Population data was obtained from Statistics South Africa. Results Pedestrians' injuries decreased from 7 445 to 6 288 (incidence risk: 241 to 193 per 100 000) from 200 I to 2006. Annual case fatality rose from 4.9% (366 deaths in 200 I) to 6.8% (430 deaths in 2006). Child pedestrians aged 5 to 9 years had a 77% increased risk of injury relative to other children. The fatality risk ratio of male to female pedestrians was 3.8 (95% Confidence Interval: 1.7 to 9.3). Male drivers aged 30 to 34 years had a 68% increased collision risk relative to all other male drivers and eight times (Incidence risk ratio: 8.0; 95% Confidence Interval: 6.2 to 10.3) the risk of female drivers. Only 3.4% of collisions occurred on freeways but accounted for 19.6% of pedestrian fatalities. Few (1.5%) collisions involving pedestrians occurred at night in unlit conditions but constituted more than four times the number of fatalities as number of collisions in these conditions. / Thesis (MMed.)- University of KwaZulu-Natal, Durban, 2009.
13

Göteborg kommuns utdelning av broddar till kommunens äldre : Effekten på fallskador till följd av halka på is och snö / Gothenburg municipality’s distribution of anti-slip devices to the municipality’s elderly : The effect of fall related injuries due to slipping on ice and snow

Holmberg, Robin January 2017 (has links)
Inledning: Göteborgs kommun implementerade år 2013 en intervention i form av gratis utdelning av broddar till kommunens äldre befolkning (65+), i ett försök att reducera antalet fall/halkolyckor på is/snö. Syftet med detta papper var att se över om interventionen hade haft en effekt på incidensen av fotgängarolyckor gällande fall/halkskador bland kommunens äldre befolkning. Metod: Pappret applicerade en kontrollerad före– och efterstudie för att se på skillnader mellan en föreperiod (2009–2012), då halkskydd ännu inte var utdelade, mot en efterperiod (2013–2016) då interventionen hade implementerats. Resultat: När interventionsgruppen (65+) jämfördes mot kontrollgruppen (16–64) hade antalet incidenser på is/snö minskat med 34.36 fall/halkolyckor per 100 000 efter utdelningen av broddar. Liknande trender kunde inte utläsas när analyser gjordes mot närliggande kontrollkommuner. Placebotest visade heller inte på någon signifikant effekt för Göteborg då placebokontroller utfördes för tidigare observerade perioder (2003–2010). Slutsats: Resultaten tyder på att antalet fall/halkincidenser på is/snö bland äldre invånare i Göteborgs kommun har sjunkit med 36 procent efter kommunens åtgärd. / Introduction: In 2013, Gothenburg municipality implemented an intervention in the form of free distribution of anti-slip devices to the municipality’s elderly population (65+) to reduce the amount of falls/slips on ice/snow. The aim of this paper was to evaluate if the intervention had an effect on the incidence of pedestrian accidents involving falls/slips among the municipality’s elderly. Methods: This paper applied a controlled before-and-after study to test for differences between a before period (2009-2012), when anti-slip devices were not yet distributed, to an after period (2013-2016) when the intervention had been implemented. Results: When the intervention group (age 65+ years) was compared to the control group (age 16–64 years), the number of incidences had significantly decreased by 34.36 falls/slips on ice/snow per 100 000 person-years after the distribution of anti-slip devices had been made. Similar trends were not seen when analysis were done to nearby control municipalities. A placebo test did not show any significant effect of Gothenburg as placebo controls were made on earlier observed periods (2003-2010). Conclusion: The results suggest that the number of fall/slip incidences on ice/snow among the municipality’s elderly residents has been reduced by 36 percent after the municipal intervention.
14

Understanding Boundary Conditions for Brain Injury Prediction : Finite Element Analysis of Vulnerable Road Users

S. Alvarez, Victor January 2017 (has links)
Vulnerable road users (VRUs) are overrepresented in the statistics on severe and deadly injuries in traffic accidents, most commonly involving the head. The finite element (FE) method presents the possibility to model complex interactions between the human body and vehicles in order to better understand the injury mechanisms. While the rapid development of computer capacity has allowed for increasingly detailed FE-models, there is always a benefit of reducing the studied problem. Due to its material properties, the brain is more sensitive to rotational motion than to purely linear, resulting in complex injury causation. When studying brain injuries caused by a direct impact to the head, simulations using an isolated head model significantly increases efficiency compared to using a complete human body model. Also evaluation of head protective systems uses isolated mechanical head representations. It is not, however, established the extent to which the boundary conditions of the head determine the outcome of brain injuries. FE models of both the entire human body and the isolated head were used in this thesis to study the effect of the body, as well as active neck muscle tension, on brain injury outcome in VRU accidents. A pediatric neck model was also developed to enable the study of age-specific effects. A vehicle windscreen model was developed to evaluate the necessity of capturing the failure deformation during pedestrian head impacts. It was shown that the influence of the neck and body on brain injury prediction is greater in longer duration impacts, such as pedestrian head-to-windscreen impacts with an average difference of 21%. In accidents with shorter duration impacts, such as head-to-ground bicycle accidents, the average influence was between 3-12%. The influence did not consistently increase or limit the severity, and was dependent on the degree of rotation induced by the impact, as well as the mode of deformation induced in the neck. It was also shown that the predicted brain injury severity is dependent on capturing the large deformations of fractured windscreen, with the greatest effect near the windscreen frame. The pediatric neck model showed a large effect of age-dependent anatomical changes on inertial head loading, making it a promising tool to study the age-dependent effects in VRU accidents. / <p>QC 20171013</p>
15

Profile of pedestrian road traffic crash fatalities on the R71 road admitted at Polokwane forensic pathology

Mphatja, Tebogo Wilhemina January 2022 (has links)
Thesis (M.Med. (Forensic Pathology)) -- University of Limpopo, 2022 / Introduction and background: Road traffic fatalities remain a worldwide burden with more than half of those fatalities comprising of vulnerable road users (pedestrians, cyclists and motorcyclists). This prompted the World Health Organization and United Nations to establish Sustainable Developmental Goals aimed at reducing road traffic crashes. The study explored factors relating to pedestrian fatalities on the R71 road, which may inform future interventions to enhance pedestrian safety. Aim: The study aimed at profiling pedestrian road traffic crash fatalities on the R71 road admitted at Polokwane Forensic Pathology Services. Methodology: A quantitative descriptive study utilising total population purposive sampling of pedestrians that demised because of R71 road traffic crashes over a 3-year period was done. There were 65 cases studied. Results: The study revealed that the fatalities were more male adult pedestrians than females, who were between 20 -39 years old. Majority of those pedestrians were wearing dark coloured clothing with no reflectors on. The pedestrian fatalities were mostly seen over the weekend and between evening and midnight. The fatalities peaked in December and February (summer season). The common locality of the pedestrian fatalities was Mankweng and Mentz village (Area 3). Most of those pedestrians sustained head injuries. Conclusion: Contributory factors and injuries of those pedestrian fatalities that demised because of R71 road traffic crashes were identified, which some were similar to those already highlighted in literature.
16

Modeling of low illuminance road lighting condition using road temporal profile

Dong, Libo 05 October 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Pedestrian Automatic Emergency Braking (PAEB) system for avoiding/mitigating pedestrian crashes have been equipped on some passenger vehicles. At present, there are many e orts for the development of common standard for the performance evaluation of PAEB. The Transportation Active Safety Institute (TASI) at Indiana University-Purdue University-Indianapolis has been studying the problems and ad- dressing the concerns related to the establishment of such a standard with support from Toyota Collaborative Safety Research Center (CSRC). One of the important components in the PAEB evaluation is the development of standard testing facili- ties at night, in which 70% pedestrian crash social costs occurs [1]. The test facility should include representative low-illuminance environment to enable the examination of sensing and control functions of di erent PAEB systems. This thesis work focuses on modeling low-illuminance driving environment and describes an approach to recon- struct the lighting conditions. The goal of this research is to characterize and model light sources at a potential collision case at low-illuminance environment and deter- mine possible recreation of such environment for PAEB evaluation. This research is conducted in ve steps. The rst step is to identify lighting components that ap- pear frequently on a low-illuminance environment that a ect the performance of the PAEB. The identi ed lighting components include ambient light, same side/opposite side light poles, opposite side car headlight. Next step is to collect all potential pedes- trian collision cases at night with GPS coordinate information from TASI 110 CAR naturalistic driving study video database. Thirdly, since ambient lighting is relatively random and lack of a certain pattern, ambient light intensity for each potential col- lision case is de ned and processed as the average value of a region of interest on all video frames in this case. Fourth step is to classify interested light sources from the selected videos. The temporal pro le method, which compressing region of interest in video data (x,y,t) to image data (x,y), is introduced to scan certain prede ned region on the video. Due to the fact that light sources (except ambient light) impose distinct light patterns on the road, image patterns corresponding to speci c light sources can be recognized and classi ed. All light sources obtained are stamped with GPS coordinates and time information which are provided in corresponding data les along with the video. Lastly, by grouping all light source information of each repre- sentative street category, representative light description of each street category can be generated. Such light description can be used for lighting construction of PAEB test facility.
17

Childhood pedestrian mortality in Johannesburg, South Africa : magnitude, determinants and neighbourhood characteristics

Bulbulia, Abdulsamed 11 1900 (has links)
Child pedestrian injury and mortality is an issue of significant public health concern in the city of Johannesburg, Gauteng, in South Africa. Since there is a paucity of studies in the last decade or more on fatal childhood traffic and non-traffic injuries in Johannesburg, this study aspires to address the disproportion in this domain of research, and provide more recent, and comprehensive empirical evidence over a ten-year period. The overarching aim of this study was to describe and examine the magnitude, circumstances, and neighbourhood characteristics of fatal pedestrian injuries among children (0-14 years) in Johannesburg for the period from 2001 to 2010. More specifically, the objectives of the study were: firstly, to provide a comprehensive epidemiological description of the magnitude, trends and occurrence of pedestrian mortality among children; secondly, to describe and examine the epidemiology of child pedestrian mortality in relation to children as motor vehicle passengers; thirdly, to describe and examine child pedestrian mortality in relation to non-traffic injuries, in particular, burns and drowning; and fourthly, to assess the influence of neighbourhood characteristics on child pedestrian mortality. The study conceptualised pedestrian road safety within an ecological systems framework. The study used quantitative descriptive, and multivariate logistic regression methods of analysis to examine child pedestrian mortality data. The study drew on data from the National Injury Mortality Surveillance System (NIMSS) and the Census 2001. The main findings indicated that black, male children aged 5 to 9 years (11.02/100 000) are the most vulnerable, and that mortality occurred predominantly during the afternoons and early evenings (12h00-16h00 and 16h00-21h00), over weekends, during school holidays, and to a lesser extent, during non-holiday months. In addition, neighbourhood characteristics that reflected concentrations of disadvantage, single female-headed households and residentially stable areas were associated with child pedestrian mortality. The study findings highlight the need for critical action in terms of investment in child pedestrian safety research, and appropriate prevention initiatives guided by stringent evidenced-based studies, and the design of safe pedestrian, vehicular and urban environments. / Psychology / D. Phil. (Psychology)
18

Childhood pedestrian mortality in Johannesburg, South Africa : magnitude, determinants and neighbourhood characteristics

Bulbulia, Abdulsamed 11 1900 (has links)
Child pedestrian injury and mortality is an issue of significant public health concern in the city of Johannesburg, Gauteng, in South Africa. Since there is a paucity of studies in the last decade or more on fatal childhood traffic and non-traffic injuries in Johannesburg, this study aspires to address the disproportion in this domain of research, and provide more recent, and comprehensive empirical evidence over a ten-year period. The overarching aim of this study was to describe and examine the magnitude, circumstances, and neighbourhood characteristics of fatal pedestrian injuries among children (0-14 years) in Johannesburg for the period from 2001 to 2010. More specifically, the objectives of the study were: firstly, to provide a comprehensive epidemiological description of the magnitude, trends and occurrence of pedestrian mortality among children; secondly, to describe and examine the epidemiology of child pedestrian mortality in relation to children as motor vehicle passengers; thirdly, to describe and examine child pedestrian mortality in relation to non-traffic injuries, in particular, burns and drowning; and fourthly, to assess the influence of neighbourhood characteristics on child pedestrian mortality. The study conceptualised pedestrian road safety within an ecological systems framework. The study used quantitative descriptive, and multivariate logistic regression methods of analysis to examine child pedestrian mortality data. The study drew on data from the National Injury Mortality Surveillance System (NIMSS) and the Census 2001. The main findings indicated that black, male children aged 5 to 9 years (11.02/100 000) are the most vulnerable, and that mortality occurred predominantly during the afternoons and early evenings (12h00-16h00 and 16h00-21h00), over weekends, during school holidays, and to a lesser extent, during non-holiday months. In addition, neighbourhood characteristics that reflected concentrations of disadvantage, single female-headed households and residentially stable areas were associated with child pedestrian mortality. The study findings highlight the need for critical action in terms of investment in child pedestrian safety research, and appropriate prevention initiatives guided by stringent evidenced-based studies, and the design of safe pedestrian, vehicular and urban environments. / Psychology / D.Phil. (Psychology)
19

A new approach for pedestrian tracking and status analysis

Jiang, Pingge January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Pedestrian and vehicle interaction analysis in a naturalistic driving environment can provide useful information for designing vehicle-pedestrian crash warning/mitigation systems. Many researchers have used crash data to understand and study pedestrian behaviors and interactions between vehicles and pedestrian during crash. However, crash data may not provide detailed pedestrian-vehicle interaction information for us. In this thesis, we designed an automatic pedestrian tracking and status analysis method to process and study pedestrian and vehicle interactions. The proposed pedestrian tracking and status analysis method includes pedestrian detection, pedestrian tracking and pedestrian status analysis modules. The main contributions of this thesis are: we designed a new pedestrian tracking method by learning the pedestrian appearance and also their motion pattern. We designed a pedestrian status estimation method by using our tracking results and thus helped estimate the possibility of collision. Our preliminary experiment results using naturalistic driving data showed promising results.
20

Pedestrian Protection Using the Integration of V2V Communication and Pedestrian Automatic Emergency Braking System

Tang, Bo 01 December 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The Pedestrian Automatic Emergency Braking System (PAEB) can utilize on-board sensors to detect pedestrians and take safety related actions. However, PAEB system only benefits the individual vehicle and the pedestrians detected by its PAEB. Additionally, due to the range limitations of PAEB sensors and speed limitations of sensory data processing, PAEB system often cannot detect or do not have sufficient time to respond to a potential crash with pedestrians. For further improving pedestrian safety, we proposed the idea for integrating the complimentary capabilities of V2V and PAEB (V2V-PAEB), which allows the vehicles to share the information of pedestrians detected by PAEB system in the V2V network. So a V2V-PAEB enabled vehicle uses not only its on-board sensors of the PAEB system, but also the received V2V messages from other vehicles to detect potential collisions with pedestrians and make better safety related decisions. In this thesis, we discussed the architecture and the information processing stages of the V2V-PAEB system. In addition, a comprehensive Matlab/Simulink based simulation model of the V2V-PAEB system is also developed in PreScan simulation environment. The simulation result shows that this simulation model works properly and the V2V-PAEB system can improve pedestrian safety significantly.

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