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1.
Sensors (Basel) ; 23(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37112424

RESUMO

Lane detection in driving situations is a critical module for advanced driver assistance systems (ADASs) and automated cars. Many advanced lane detection algorithms have been presented in recent years. However, most approaches rely on recognising the lane from a single or several images, which often results in poor performance when dealing with extreme scenarios such as intense shadow, severe mark degradation, severe vehicle occlusion, and so on. This paper proposes an integration of steady-state dynamic equations and Model Predictive Control-Preview Capability (MPC-PC) strategy to find key parameters of the lane detection algorithm for automated cars while driving on clothoid-form roads (structured and unstructured roads) to tackle issues such as the poor detection accuracy of lane identification and tracking in occlusion (e.g., rain) and different light conditions (e.g., night vs. daytime). First, the MPC preview capability plan is designed and applied in order to maintain the vehicle on the target lane. Second, as an input to the lane detection method, the key parameters such as yaw angle, sideslip, and steering angle are calculated using a steady-state dynamic and motion equations. The developed algorithm is tested with a primary (own dataset) and a secondary dataset (publicly available dataset) in a simulation environment. With our proposed approach, the mean detection accuracy varies from 98.7% to 99%, and the detection time ranges from 20 to 22 ms under various driving circumstances. Comparison of our proposed algorithm's performance with other existing approaches shows that the proposed algorithm has good comprehensive recognition performance in the different dataset, thus indicating desirable accuracy and adaptability. The suggested approach will help advance intelligent-vehicle lane identification and tracking and help to increase intelligent-vehicle driving safety.

2.
Sensors (Basel) ; 23(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687841

RESUMO

With the increasing use of automated vehicles (AVs) in the coming decades, government authorities and private companies must leverage their potential disruption to benefit society. Few studies have considered the impact of AVs towards mode shift by considering a range of factors at the city level, especially in Australia. To address this knowledge gap, we developed a system dynamic (SD)-based model to explore the mode shift between conventional vehicles (CVs), AVs, and public transport (PT) by systematically considering a range of factors, such as road network, vehicle cost, public transport supply, and congestion level. By using Melbourne's Transport Network as a case study, the model simulates the mode shift among AVs, CVs, and PT modes in the transportation system over 50 years, starting from 2018, with the adoption of AVs beginning in 2025. Inputs such as current traffic, road capacity, public perception, and technological advancement of AVs are used to assess the effects of different policy options on the transport systems. The data source used is from the Victorian Integrated Transport Model (VITM), provided by the Department of Transport and Planning, Melbourne, Australia, data from the existing literature, and authors' assumptions. To our best knowledge, this is the first time using an SD model to investigate the impacts of AVs on mode shift in the Australian context. The findings suggest that AVs will gradually replace CVs as another primary mode of transportation. However, PT will still play a significant role in the transportation system, accounting for 50% of total trips by person after 2058. Cost is the most critical factor affecting AV adoption rates, followed by road network capacity and awareness programs. This study also identifies the need for future research to investigate the induced demand for travel due to the adoption of AVs and the application of equilibrium constraints to the traffic assignment model to increase model accuracy. These findings can be helpful for policymakers and stakeholders to make informed decisions regarding AV adoption policies and strategies.

3.
Transp Res Part A Policy Pract ; 154: 186-202, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34707330

RESUMO

Understanding changes in travel behavior during the spread of pandemic diseases such as COVID-19 is important to develop a resilient transportation system. Since one of the most important ways to prevent the spread of this virus is to keep a safe distance from other people (i.e. social distancing), it has implications for the operations of public transportation as compared to other modes of transportation due to the confinement of a large number of passengers in enclosed space. This study investigated the effect of the spread of COVID-19 on crowding perception and crowding disutility in metro rail system of Tehran. Two surveys were conducted before and during the COVID-19. The stated preference data were analyzed by mixed logit models with the lognormal distribution. Results revealed that the value of crowding increased during the pandemic. Tracking the changes of crowding perception caused by COVID-19 shows that low comfort scores were observed at crowding levels where seats were taken, and the density of standees was high (i.e. not possible to maintain social distancing). During the outbreak of COVID-19, crowding has more disutility for rail passengers and the value of having a seat while traveling increased. Understanding passengers' perceptions of crowding as examined in this study will assist transport operators, and planners maintain the critical functionality of public transport systems and manage risks of mass transportation during the pandemic and beyond.

4.
Sci Rep ; 13(1): 1842, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725959

RESUMO

The digital transformation of Automated Vehicles (AVs) has raised concerns in the cyber realm among prospective AV consumers. However, there is a dearth of empirical research on how cyber obstacles may impact the operation of AVs. To address this knowledge gap, this study examines the six critical cyber impediments (data privacy, AV connectivity, ITS infrastructure, lack of cybersecurity regulations, AV cybersecurity understanding, and AV cyber-insurance) that influence the deployment of AVs. The impact of gender, age, income level, and individual AV and cybersecurity knowledge on these obstacles are statistically assessed using a sample of 2061 adults from the United States, the United Kingdom, New Zealand, and Australia. The research revealed intriguing empirical findings on all cyber barriers in the form of a trichotomy: participants' education level, understanding of AVs, and cybersecurity knowledge. As education levels increase, the significance of a cyber barrier to AV deployment decreases; however, as AV comprehension and cybersecurity knowledge increase, the perception of a cyber barrier becomes significantly more important. In addition, the study demonstrates differences in perceptions of cyber barriers and AV deployments based on gender, age, income, and geographic location. This study's findings on cyber barriers and AV deployment have implications for academia and industry.

5.
Accid Anal Prev ; 186: 107054, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37023653

RESUMO

Technological advancements in Connected and Automated Vehicles (CAVs), particularly the integration of diverse stakeholder groups (communication service providers, road operators, automakers, repairers, CAV consumers, and the general public) and the pursuit of new economic opportunities, have resulted in the emergence of new technical, legal, and social challenges. The most pressing challenge is deterring criminal behaviour in both the physical and cyber realms through the adoption of CAV cybersecurity protocols and regulations. However, the literature lacks a systematic decision tool to analyze the impact of the potential cybersecurity regulations for dynamically interacting stakeholders, and to identify the leverage points to minimise the cyber-risks. To address this knowledge gap, this study uses systems theory to develop a dynamic modelling tool to analyze the indirect consequences of potential CAVs cybersecurity regulations in the medium to long term. It is hypothesized that CAVs Cybersecurity Regulatory Framework (CRF) is the property of the entire ITS stakeholders. The CRF is modelled using the System Dynamic based Stock-and-Flow-Model (SFM) technique. The SFM is founded on five critical pillars: the Cybersecurity Policy Stack, the Hacker's Capability, Logfiles, CAV Adopters, and intelligence-assisted traffic police. It is found that decision-makers should focus on three major leverage points: establishing a CRF grounded on automakers' innovation; sharing risks in eliminating negative externalities associated with underinvestment and knowledge asymmetries in cybersecurity; and capitalising on massive CAV-generated data in CAV operations. The formal integration of intelligence analysts and computer crime investigators to strengthen traffic police capabilities is pivotal. Recommendations for automakers include data-profiteering in CAV design, production, sales, marketing, safety enhancements and enabling consumer data transparency.Furthermore, CAVs-CRF necessitate a balanced approach to the trade-off between: i) data accessibility constraints on CAV automakers and ITS service providers; ii) regulator command and control thresholds; iii) automakers' business investment protection; and iv) consumers' data privacy guard.


Assuntos
Acidentes de Trânsito , Veículos Autônomos , Humanos , Acidentes de Trânsito/prevenção & controle , Comunicação , Segurança Computacional , Inteligência
6.
Accid Anal Prev ; 192: 107231, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37531856

RESUMO

Pedestrian safety is a critical issue in the United Kingdom (UK) as pedestrians are the most vulnerable road users. Despite numerous studies on pedestrian-vehicle crashes globally, limited research has been conducted to explore the factors contributing to such incidents in the UK, especially on rural roads. Therefore, this study aimed to investigate the severity of pedestrian injuries sustained on rural roads in the UK, including crashes at intersections and non-intersections. We utilized the STATS19 dataset, which provided comprehensive road safety data from 2015 to 2019. To overcome the challenges posed by heterogeneity in the data, we employed a Latent Class Analysis to identify homogeneous clusters of crashes. Additionally, we utilized the Ordered Probit model to identify contributing factors within each cluster. Our findings revealed that various factors had distinct effects on the severity of pedestrian injuries at intersections and non-intersections. Several parameters like the pedestrian location in footway and one-way roads are only statistically significant in the intersection section. Certain factors such as the day of the week, the pedestrian's location in a refuge, and minor roads (class B roads) were found to be significant only in the non-intersection section.Parameters includingpedestrians aged over 65 years and under 15 years, drivers under 25 years, male drivers and pedestrians, darkness, heavy vehicles, speed limits exceeding 96 km/h (60 mph), major roads (class A roads), and single carriageway roadsare significant in both sections. The study proposes various measures to mitigate the severity of pedestrian-vehicle crashes, such as improving lighting conditions, enhancing pedestrian infrastructure, reducing speed limits in crash-prone areas, and promoting education and awareness among pedestrians and drivers. The findings and suggested measures could help policymakers and practitioners develop effective strategies and interventions to reduce the severity of these incidents and enhance pedestrian safety.


Assuntos
Pedestres , Ferimentos e Lesões , Humanos , Masculino , Idoso , Acidentes de Trânsito , Análise por Conglomerados , Análise de Classes Latentes , Reino Unido/epidemiologia , Ferimentos e Lesões/epidemiologia
7.
J Safety Res ; 81: 78-90, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35589308

RESUMO

INTRODUCTION: The safety of pedestrians is a major concern in Victoria, Australia. Despite the considerable number of pedestrian fatalities and injuries in traffic crashes, a limited number of studies focused on pedestrian crash severity in Victoria. METHODS: This study investigates and identifies the influential factors determining the severity of pedestrian injuries in traffic crashes in Victoria by using crash data from 2010 to 2019. An unordered multinomial logit model and an ordered logit model are developed for this purpose. RESULTS: The results indicate that pedestrian crashes on weekends, in the period of 10 a.m. to 10 p.m., on dark streets, at intersections, in areas with a speed limit above 50 km/h, and on medians or footpaths are associated with a higher probability of severe and fatal injuries. Male pedestrians, children, and older adults (>59) were more likely to sustain a higher level of injury in crashes. Concerning the driver characteristics, no significant relationship was found between pedestrian injury severity and driver gender and license status, but older drivers were more likely to cause severe and fatal injuries. Pedestrian collisions with motorcycles, heavy vehicles, light commercial vehicles, bus/minibus/coach, and trams increase the probability of more severe injuries compared to cars. Moreover, older vehicles are associated with a higher probability of severe pedestrian injuries. Comparison of the model results illustrated that the MNL model was slightly better fitted on the data than the ordered logit model, but the conclusions inferred from these two models were generally similar. PRACTICAL APPLICATION: To reduce the injuries of pedestrian crashes, we recommend improving lighting conditions and sidewalk design, implementing speed reduction strategies at high pedestrian activity areas, introducing more pedestrian crossings at midblock, installing warning signs to drivers, and discouraging the use of vehicles that are more than 20 years old.


Assuntos
Pedestres , Ferimentos e Lesões , Acidentes de Trânsito , Adulto , Idoso , Criança , Humanos , Modelos Logísticos , Masculino , Fatores de Risco , Vitória/epidemiologia , Ferimentos e Lesões/epidemiologia , Adulto Jovem
8.
Accid Anal Prev ; 165: 106515, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890922

RESUMO

Emerging Connected and Autonomous Vehicles (CAVs) technology have a ubiquitous communication framework. It poses security challenges in the form of cyber-attacks, prompting rigorous cybersecurity measures. There is a lack of knowledge on the anticipated cause-effect relationships and mechanisms of CAVs cybersecurity and the possible system behaviour, especially the unintended consequences. Therefore, this study aims to develop a conceptual System Dynamics (SD) model to analyse cybersecurity in the complex, uncertain deployment of CAVs. Specifically, the SD model integrates six critical avenues and maps their respective parameters that either trigger or mitigate cyber-attacks in the operation of CAVs using a systematic theoretical approach. These six avenues are: i) CAVs communication framework, ii) secured physical access, iii) human factors, iv) CAVs penetration, v) regulatory laws and policy framework, and iv) trust-across the CAVs-industry and among the public. Based on the conceptual model, various system archetypes are analysed. "Fixes that Fail", in which the upsurge in hacker capability is the unintended natural result of technology maturity, requires continuous efforts to combat it. The primary mitigation steps are human behaviour analysis, knowledge of motivations and characteristics of CAVs cyber-attackers, CAVs users and Original Equipment Manufacturers education. "Shifting the burden", where policymakers counter the perceived cyber threats of hackers by updating legislation that also reduces CAVs adaptation by imitations, indicated the need for calculated regulatory and policy intervention. The "limits to success" triggered by CAVs penetration increase the defended hacks to establish regulatory laws, improve trust, and develop more human analysis. However, it may also open up caveats for cyber-crimes and alert that CAVs deployment to be alignment with the intended goals for enhancing cybersecurity. The proposed model can support decision-making and training and stimulate the roadmap towards an optimized, self-regulating, and resilient cyber-safe CAV system.


Assuntos
Acidentes de Trânsito , Veículos Autônomos , Segurança Computacional , Ciclofosfamida , Humanos , Motivação
9.
Accid Anal Prev ; 151: 105990, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484970

RESUMO

Despite many studies on exploring the behaviors of pedestrians crossing the road, there is a need for comprehensive studies that identify the factors that may influence pedestrians crossing behavior at signalized and unsignalized intersections. This study aims to comprehensively examine the influence of gender, age group, group-crossing, technological devices and carrying items on pedestrians crossing behaviors at signalized and unsignalized crosswalks simultaneously. Observational data of 552 pedestrians at two signalized and two unsignalized crosswalks in Tehran were collected. Temporal and spatial violations, conflict experience and collision avoidance, situational awareness, and pedestrians crossing speed were used as pedestrians crossing behaviors indicators. To model crossing behaviors, linear mixed models (LMMs) and Generalized linear mixed models (GLMMs) with fixed-effect approach were applied for the continuous outcome (pedestrians' crossing speed) and binary outcomes, respectively. Phi and Cramer's V coefficients were used to avoid multicollinearity. Results showed that traffic checks before and while crossing showed a high positive correlation with crossing at "don't walk" and flashing "don't walk" signals and conflict experience at signalized crosswalks. As compared to females, males started their crossing more on flashing "don't walk" signal and crossed the crosswalk faster. Older pedestrians exhibited more cautious behaviors at signalized intersections but less in unsignalized intersections. Alone pedestrians behaved more cautiously than groups and crossed the crosswalk more quickly. Using technological devices, regardless of their types, caused pedestrians to not exhibit one or more safe crossing indicators considered in this study. Pedestrians talking on their phones had the least cautious behaviors. Pedestrians listening to music mostly looked at the ground or straight direction rather than looking left-right for traffic. The findings from this study are a valuable resource to road authorities and policy makers to develop appropriate targeted strategies to prevent pedestrians' injuries and fatalities and improve crosswalks safety.


Assuntos
Pedestres , Acidentes de Trânsito/prevenção & controle , Feminino , Humanos , Irã (Geográfico) , Masculino , Segurança , Caminhada
10.
Int J Inj Contr Saf Promot ; 28(2): 233-242, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33820482

RESUMO

Understanding the relationship between bus-pedestrian crash severity and factors contributing to such crashes is important. However, there exists a dearth of research on the factors affecting bus-pedestrian crash severity. This study aims to fulfil this gap by investigating the factors affecting the severity of pedestrian injuries. A data set of bus-pedestrian crashes in the State of Victoria, Australia was analysed over the period of 2006 - 2019. Through the results of association rule discovery method, the factors that increase the risk of pedestrian fatality are darkness, pedestrian walking on carriageway with traffic, intersections, high speed zone, old pedestrian, young bus driver and weekend holidays. Furthermore, co-occurrence of factors that increase the risk of a pedestrian fatality were extracted. To reduce the injuries of bus-pedestrian crashes, we recommend improving the light conditions, reducing the jaywalking behaviour of pedestrians, implementing speed bumps in high speed zones and installing pedestrian detection systems on buses.13 years of bus-pedestrian crashes in Victoria, Australia was analyzed.Association rules discovery was used for modeling pedestrian fatality.Darkness, pedestrian movement, zone speed and age effect the rate of fatality.Pattern of pedestrian fatality in collision with bus was extracted.


Assuntos
Pedestres , Acidentes de Trânsito , Humanos , Veículos Automotores , Vitória/epidemiologia , Caminhada
11.
J Safety Res ; 79: 246-256, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34848005

RESUMO

INTRODUCTION: In recent years, Australia is seeing an increase in the total number of cyclists. However, the rise of serious injuries and fatalities to cyclists has been a major concern. Understanding the factors affecting the fatalities and injuries of bicyclists in crashes with motor vehicles is important to develop effective policy measures aimed at improving the safety of bicyclists. This study aims to identify the factors affecting motor vehicle-bicycle (MVB) crashes in Victoria, Australia and introducing effective countermeasures for the identified risk factors. METHOD: A data set of 14,759 MVB crash records from Victoria, Australia between 2006 and 2019 was analyzed using the binary logit model and latent class clustering. RESULTS: It was observed that the factors that increase the risk of fatalities and serious injuries of bicyclists (FSI) in all clusters are: elderly bicyclist, not using a helmet, and darkness condition. Likewise, in areas with no traffic control, clear weather, and dry surface condition (cluster 1), high speed limits increase the risk of FSI, but the occurrence of MVB crashes in cross intersection and T-intersection has been significantly associated with a reduction in the risk of FSI. In areas with traffic control and unfavorable weather conditions (cluster 2), wet road surface increases the risk of FSI, but the areas with give way sign and pedestrian crossing signs reduce the risk of FSI. Practical Applications: Recommendations to reduce the risk of fatalities or serious injury to bicyclists are: improvement of road lighting and more exposure of bicyclists using reflective clothing and reflectors, separation of the bicycle and vehicle path in mid blocks especially in high-speed areas, using a more stable bicycle for the older people, monitoring helmet use, improving autonomous emergency braking, and using bicyclist detection technology for vehicles.


Assuntos
Acidentes de Trânsito , Ciclismo , Idoso , Ciclismo/lesões , Análise por Conglomerados , Humanos , Modelos Logísticos , Veículos Automotores , Vitória/epidemiologia
12.
J Safety Res ; 76: 73-82, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33653571

RESUMO

INTRODUCTION: Buses are different vehicles in terms of dimensions, maneuverability, and driver's vision. Although bus traveling is a safe mode to travel, the number of annual bus crashes cannot be neglected. Moreover, limited studies have been conducted on the bus involved in fatal crashes. Therefore, identification of the contributing factors in the bus involved fatal crashes can reduce the risk of fatality. METHOD: Data set of bus involved crashes in the State of Victoria, Australia was analyzed over the period of 2006-2019. Clustering of crash data was accomplished by dividing them into homogeneous categories, and by implementing association rules discovery on the clusters, the factors affecting fatality in bus involved crashes were extracted. RESULTS: Clustering results show bus crashes with all vehicles except motor vehicles and weekend crashes have a high rate of fatality. According to the association rule discovery findings, the factors that increase the risk of bus crashes with non-motor vehicles are: old bus driver, collision with pedestrians at signalized intersections, and the presence of vulnerable road users. Likewise, factors that increase the risk of fatality in bus involved crashes on weekends are: darkness of roads in high-speed zones, pedestrian presence at highways, bus crashes with passenger car by a female bus driver, and the occurrence of multi-vehicle crashes in high-speed zones. Practical Applications: The study provides a sequential pattern of factors, named rules that lead to fatality in bus involved crashes. By eliminating or improving one or all of the factors involved in rules, fatal bus crashes may be prevented. The recommendations to reduce fatality in bus crashes are: observing safe distances with the buses, using road safety campaigns to reduce pedestrians' distracted behavior, improving the lighting conditions, implementing speed bumps and rumble strips in high-speed zones, installing pedestrian detection systems on buses and setting special bus lanes in crowded areas.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Mineração de Dados , Veículos Automotores/classificação , Pedestres/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Vitória , Adulto Jovem
13.
Accid Anal Prev ; 148: 105837, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33120180

RESUMO

Modern-day Connected and Autonomous Vehicles (CAVs) with more than 100 million code lines, running up-to a hundred Electronic Control Units (ECUs) will create and exchange digital information with other vehicles and intelligent transport networks. Consequently, ubiquitous internal and external communication (controls, commands, and data) within all CAV-related nodes is inevitably the gatekeeper for the smooth operation. Therefore, it is a primary vulnerable area for cyber-attacks that entails stringent and efficient measures in the form of "cybersecurity". There is a lack of systematic and comprehensive review of the literature on cyber-attacks on the CAVs, respective mitigation strategies, anticipated readiness, and research directions for the future. This study aims to analyse, synthesise, and interpret critical areas for the roll-out and progression of CAVs in combating cyber-attacks. Specifically, we described in a structured way a holistic view of potentially critical avenues, which lies at the heart of CAV cybersecurity research. We synthesise their scope with a particular focus on ensuring effective CAVs deployment and reducing the probability of cyber-attack failures. We present the CAVs communication framework in an integrated form, i.e., from In-Vehicle (IV) communication to Vehicle-to-Vehicle (V2X) communication with a visual flowchart to provide a transparent picture of all the interfaces for potential cyber-attacks. The vulnerability of CAVs by proximity (or physical) access to cyber-attacks is outlined with future recommendations. There is a detailed description of why the orthodox cybersecurity approaches in Cyber-Physical System (CPS) are not adequate to counter cyber-attacks on the CAVs. Further, we synthesised a table with consolidated details of the cyber-attacks on the CAVs, the respective CAV communication system, its impact, and the corresponding mitigation strategies. It is believed that the literature discussed, and the findings reached in this paper are of great value to CAV researchers, technology developers, and decision-makers in shaping and developing a robust CAV-cybersecurity framework.


Assuntos
Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/psicologia , Condução de Veículo/normas , Automóveis/normas , Segurança Computacional/normas , Segurança Computacional/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Condução de Veículo/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Segurança Computacional/estatística & dados numéricos , Feminino , Previsões , Guias como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Safety Res ; 73: 17-24, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32563389

RESUMO

INTRODUCTION: Motorcyclists are exposed to more fatalities and severe injuries per mile of travel as compared to other vehicle drivers. Moreover, crashes that take place at intersections are more likely to result in serious or fatal injuries as compared to those that occur at non-intersections. Therefore, the purpose of this study is to evaluate the contributing factors to motorcycle crash severity at intersections. METHOD: A data set of 7,714 motorcycle crashes at intersections in the State of Victoria, Australia was analyzed over the period of 2006-2018. The multinomial logit model was used for evaluating the motorcycle crashes. The severity of motorcycle crashes was divided into three categories: minor injury, serious injury and fatal injury. The risk factors consisted of four major categories: motorcyclist characteristics, environmental characteristics, intersection characteristics and crash characteristics. RESULTS: The results of the model demonstrated that certain factors increased the probability of fatal injuries. These factors were: motorcyclists aged over 59 years, weekend crashes, midnight/early morning crashes, morning rush hours crashes, multiple vehicles involved in the crash, t-intersections, crashes in towns, crashes in rural areas, stop or give-way intersections, roundabouts, and uncontrolled intersections. By contrast, factors such as female motorcyclists, snowy or stormy or foggy weather, rainy weather, evening rush hours crashes, and unpaved roads reduced the probability of fatal injuries. Practical Applications: The results from our study demonstrated that certain treatment measures for t-intersections may reduce the probability of fatal injuries. An effective way for improving the safety of stop or give-way intersections and uncontrolled intersections could be to convert them to all-way stop controls. Further, it is recommended to educate the older riders that with ageing, there are physiological changes that occur within the body which can increase both crash likelihood and injury severity.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Motocicletas/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Vitória , Adulto Jovem
15.
Accid Anal Prev ; 95(Pt B): 405-416, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26519346

RESUMO

A recent crowd stampede during a New Year's Eve celebration in Shanghai, China resulted in 36 fatalities and over 49 serious injuries. Many of such tragic crowd accidents around the world resulted from complex multi-direction crowd movement such as merging behavior. Although there are a few studies on merging crowd behavior, none of them have conducted a systematic analysis considering the impact of both merging angle and flow direction towards the safety of pedestrian crowd movement. In this study, a series of controlled laboratory experiments were conducted to examine the safety constraints of merging pedestrian crowd movements considering merging angle (60°, 90° and 180°) and flow direction under slow running and blocked vision condition. Then, macroscopic and microscopic properties of crowd dynamics are obtained and visualized through the analysis of pedestrian crowd trajectory data derived from video footage. It was found that merging angle had a significant influence on the fluctuations of pedestrian flows, which is important in a critical situation such as emergency evacuation. As the merging angle increased, mean velocity and mean flow at the measuring region in the exit corridors decreased, while mean density increased. A similar trend was observed for the number of weaving and overtaking conflicts, which resulted in the increase of mean headway. Further, flow direction had a significant impact on the outflow of the individuals while blocked vision had an influence on pedestrian crowd interactions and merging process. Finally, this paper discusses safety assessments on crowd merging behaviors along with some recommendations for future research. Findings from this study can assist in the development and validation of pedestrian crowd simulation models as well as organization and control of crowd events.


Assuntos
Aglomeração , Comportamento de Massa , Pedestres , Corrida , Segurança , Adolescente , Adulto , China , Emergências , Feminino , Humanos , Modelos Teóricos , Visão Ocular , Adulto Jovem
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