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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.
21

Evaluation Of Pedestrian Safety Around Bus Stops Using Geographic Information Systems

Yuksekol, Irem 01 September 2012 (has links) (PDF)
Pedestrians are the most vulnerable road users in terms of traffic safety. Public transit users mostly have a pedestrian trip before and/or after the transit one. Thus, pedestrian activity is produced at transit stops naturally. The main focus of this study is pedestrian safety problems around transit stops, more specifically bus stops. The proposed methodology first includes Geographic Information Systems (GIS) analyses of the pedestrian safety along the study corridors and around bus stops on them / this enables determination of accident-prone corridor segments and bus stops, respectively. Later, two analyses are studied to understand their correlation. Finally, linear regression analyses are performed to find the significant factors affecting pedestrian safety. These analyses use parameters created in the GIS analyses in the first part, as well as others (i.e. built environment, traffic network, etc.) that have potential impact on pedestrian movement or safety. In corridor safety models, the number of pedestrian accidents or accident density (or some transformation of them) is used as the dependent variable / while it is selected as the total number of accidents within a selected buffer zone in the bus stop safety models. The case study corridors are selected based on the high density of pedestrian accidents in Ankara, including the Central Business District (CBD) and four main arterials serve from CBD to different regions. The bus stops on corridors with high motorized and pedestrian flows are found to be more critical than others.
22

Pedestrian Safety and Collision Avoidance for Autonomous Vehicles

Gelbal, Sukru Yaren January 2021 (has links)
No description available.
23

Designing a Surrogate Upper Body Mass for a Projectile Pedestrian Legform

Ratliff, Adam R. 19 March 2008 (has links)
No description available.
24

Обележја страдања пешака на пешачким прелазима регулисаним светлосном сигнализацијом / Obeležja stradanja pešaka na pešačkim prelazima regulisanim svetlosnom signalizacijom / PEDESTRIAN FATALITY CHARACTERISTICS AT TRAFFIC LIGHTCONTROLLEDCROSSWALKS

Bulajić Aleksandar 23 November 2016 (has links)
<p>Основни предмет истраживања докторске дисертације представљала су обележја страдања пешака на пешачким прелазима регулисаним светлосном сигнализацијом са дефинисаним захтевима у погледу идентификације специфичних карактеристика страдања пешака и дефинисања модела понашања пешака на овим прелазима. У оквиру истраживања у циљу дефинисања обележја страдања пешака на територији града Новог Сада спроведена је свеобухватна анализа релевантних података. Резултати спроведеног истраживања указују да је намера пешака да чине недозвољени прелазак коловоза у већој мери одређена друштвеним утицајима (тј. субјективне, дескриптивне, нормативне и персоналне норме), него на основу личног мишљења (ставови и опажена контрола понашања). Анализа података показује да саобраћајне незгоде са пешацима као рањивим корисницима пута и њихове последице захтевају приступ који ће узети у обзир све специфичности као што су пол, старост, просторне и временске карактеристике, присуство алкохола, брзину итд.</p> / <p>Osnovni predmet istraživanja doktorske disertacije predstavljala su obeležja stradanja pešaka na pešačkim prelazima regulisanim svetlosnom signalizacijom sa definisanim zahtevima u pogledu identifikacije specifičnih karakteristika stradanja pešaka i definisanja modela ponašanja pešaka na ovim prelazima. U okviru istraživanja u cilju definisanja obeležja stradanja pešaka na teritoriji grada Novog Sada sprovedena je sveobuhvatna analiza relevantnih podataka. Rezultati sprovedenog istraživanja ukazuju da je namera pešaka da čine nedozvoljeni prelazak kolovoza u većoj meri određena društvenim uticajima (tj. subjektivne, deskriptivne, normativne i personalne norme), nego na osnovu ličnog mišljenja (stavovi i opažena kontrola ponašanja). Analiza podataka pokazuje da saobraćajne nezgode sa pešacima kao ranjivim korisnicima puta i njihove posledice zahtevaju pristup koji će uzeti u obzir sve specifičnosti kao što su pol, starost, prostorne i vremenske karakteristike, prisustvo alkohola, brzinu itd.</p> / <p>The main subject researched by this doctoral disseration were the characteristics<br />of pedestrian accidents at traffic light-controlled crosswalks with the defined<br />requirements for the identification of specific characteristics of pedestrian accidents<br />and for structuring the models of pedestrian behavior at these crosswalks. Within the<br />scope of the reseach, with an aim to define the characteristics of pedestrian accidents<br />in the City of Novi Sad, a comprehensive analysis of relevant data was conducted.<br />The analysis of data indicate that traffic accidents involving pedestrians as<br />vulnerable road users and their consequences require an approach that will include<br />all specific elements, such as gender, age, space and time characteristics, amount of<br />alcohol, speed, etc.</p>
25

The impact of bus stop micro-locations on pedestrian safety in areas of main attraction

Kovacevic, Vlado S January 2005 (has links)
From the safety point of view, the bus stop is perhaps the most important part of the Bus Public Transport System, as it represents the point where bus passengers may interact directly with other road users and create conflicting situations leading to traffic accidents. For example, travellers could be struck walking to/from or boarding/alighting a bus. At these locations, passengers become pedestrians and at some stage crossing busy arterial roads at the bus stop in areas or at objects of main attraction usually outside of pedestrian designated facilities such as signal controlled intersections, zebra and pelican crossings. Pedestrian exposure to risk or risk-taking occurs when people want to cross the road in front of the stopped bus, at the rear of the bus or between the buses, particularly where bus stops are located on two-way roads (i.e. within the mid-block of the road with side streets, at non-signalised cross-section). However, it is necessary to have a better understanding of the pedestrian road-crossing risk exposure (pedestrian crossing distraction, obscurity and behaviour) within bus stop zones so that it can be incorporated into new design, bus stop placement, and evaluation of traffic management schemes where bus stop locations will play an increasingly important role. A full range of possible incidental interactions are presented in a tabular model that looks at the most common interacting traffic movements within bus stop zones. The thesis focused on pedestrian safety, discusses theoretical foundations of bus stops, and determines the types of accident risks between bus travellers as pedestrians and motor vehicles within the zones of the bus stop. Thus, the objectives of this thesis can be summarized as follows: (I) - Classification of bus stops, particularly according to objects of main attraction (pedestrian-generating activities); (II) - Analysis of traffic movement and interactions as an accident/risk exposure in the zone of bus stops with respect to that structure; (III) - Categorizing traffic accident in the vicinity of bus stops, and to analyse the interactions (interacting movements) that occur within bus stop zones in order to discover the nature of problems; (IV) - Formulation of tabular (pedestrian traffic accident prediction) models/forms (based on traffic interactions that creating and causing possibilities of accident conflict) for practical statistical methods of those accidents related to bus stop, and; (V) - Safety aspects related to the micro-location of bus stops to assist in the micro-location design, operations of bus stop safety facilities and safer pedestrian crossing for access between the bus stop and nearby objects of attraction. The scope of this thesis focuses on the theoretical foundation of bus stop microâ??location in areas of main attractions or at objects of main attraction, and traffic accident risk types as they occur between travellers as pedestrians and vehicle flow in the zone of the bus stop. The knowledge of possible interactions leads to the identification of potential conflict situations between motor vehicles and pedestrians. The problems discussed for each given conflict situation, has a great potential in increasing the knowledge needed to prevent accidents and minimise any pedestrian-vehicle conflict in this area and to aid in the development and planning of safer bus stops.
26

The impact of bus stop micro-locations on pedestrian safety in areas of main attraction

Kovacevic, Vlado S January 2005 (has links)
From the safety point of view, the bus stop is perhaps the most important part of the Bus Public Transport System, as it represents the point where bus passengers may interact directly with other road users and create conflicting situations leading to traffic accidents. For example, travellers could be struck walking to/from or boarding/alighting a bus. At these locations, passengers become pedestrians and at some stage crossing busy arterial roads at the bus stop in areas or at objects of main attraction usually outside of pedestrian designated facilities such as signal controlled intersections, zebra and pelican crossings. Pedestrian exposure to risk or risk-taking occurs when people want to cross the road in front of the stopped bus, at the rear of the bus or between the buses, particularly where bus stops are located on two-way roads (i.e. within the mid-block of the road with side streets, at non-signalised cross-section). However, it is necessary to have a better understanding of the pedestrian road-crossing risk exposure (pedestrian crossing distraction, obscurity and behaviour) within bus stop zones so that it can be incorporated into new design, bus stop placement, and evaluation of traffic management schemes where bus stop locations will play an increasingly important role. A full range of possible incidental interactions are presented in a tabular model that looks at the most common interacting traffic movements within bus stop zones. The thesis focused on pedestrian safety, discusses theoretical foundations of bus stops, and determines the types of accident risks between bus travellers as pedestrians and motor vehicles within the zones of the bus stop. Thus, the objectives of this thesis can be summarized as follows: (I) - Classification of bus stops, particularly according to objects of main attraction (pedestrian-generating activities); (II) - Analysis of traffic movement and interactions as an accident/risk exposure in the zone of bus stops with respect to that structure; (III) - Categorizing traffic accident in the vicinity of bus stops, and to analyse the interactions (interacting movements) that occur within bus stop zones in order to discover the nature of problems; (IV) - Formulation of tabular (pedestrian traffic accident prediction) models/forms (based on traffic interactions that creating and causing possibilities of accident conflict) for practical statistical methods of those accidents related to bus stop, and; (V) - Safety aspects related to the micro-location of bus stops to assist in the micro-location design, operations of bus stop safety facilities and safer pedestrian crossing for access between the bus stop and nearby objects of attraction. The scope of this thesis focuses on the theoretical foundation of bus stop microâ??location in areas of main attractions or at objects of main attraction, and traffic accident risk types as they occur between travellers as pedestrians and vehicle flow in the zone of the bus stop. The knowledge of possible interactions leads to the identification of potential conflict situations between motor vehicles and pedestrians. The problems discussed for each given conflict situation, has a great potential in increasing the knowledge needed to prevent accidents and minimise any pedestrian-vehicle conflict in this area and to aid in the development and planning of safer bus stops.
27

In-depth accident investigation of pedestrian impact dynamics and development of head injury risk functions / Évaluation des conditions d'impact de la tête en cas d'accident de piéton

Peng, Yong 17 September 2012 (has links)
Les piétons comptent parmi les usagers de la route les plus vulnérables dans la mesure où ils ne bénéficient d'aucune protection en cas d'impact avec un véhicule automobile. Plus de 1,17 millions de personnes sont tués sur la route de part le monde dont environ 65% ce piétons. Les blessures de la tête, souvent fatales, concernent environ 30 % des blessures enregistrées. Ces blessures conduisent à des incapacités de longue durée avec un coût sociétal et économique immense. Il est par conséquent essentiel de comprendre aussi bien les mécanismes d'accidents que les mécanismes de blessure de la tête afin d'intervenir sur la conception de la face avant des véhicules automobile. Dans ce contexte l'objet de la présente thèse est d'analyser la répons dynamique du piton en cas d'accident et ce contribuer au développement de critères de blessure de la tête. Dans le but d'étudier l'influence de la position du piéton, de la géométrie de la face avant du véhicule et de sa vitesse initiale sur la cinématique du piéton et les conditions d'impact de la tête, une simulation multi-corps a été mise en place. Les résultats de ces simulations donnent la vitesse et l'angle d'impact de la tête et la position de l'impact sur le véhicule. Cette analyse paramètrique a été conduite sur cinq types de véhicules et pour un modèle humain adulte et enfant de 6 ans et a permis de consolider les connaissances sur la conditions d'impact de la tête en comparaison avec les tests normatifs en vigueur.[...] / Pedestrians are regarded as an extremely vulnerable and high-risk group of road users since they are unprotected in vehicle impacts. More than 1.17 million people throughout the world are killed in road traffic accidents each year. Where, about 65% of deaths involve pedestrians. The head injuries in vehicle-pedestrian collisions accounted for about 30% of all reported injuries on different body regions, which often resulted in a fatal consequence. Such injuries can result in disabilities and long-term sequence, which lead to significant social costs. It is therefore important to study the characteristics of pedestrian accidents and understand the head injury mechanism of the pedestrian so as to improve vehicle design for pedestrian protection. The aim of this study is to investigate pedestrian dynamic response and develop head injury risk functions.In order to investigate the effect of pedestrian gait, vehicle front geometry and impact velocity on the dynamic responses of the head, the multi-body dynamic (MBD) models were used to simulate the head responses in vehicle to pedestrian collisions with different vehicle types in terms of head impact point measured with Wrap Around Distance (WAD), head relative velocity and impact angle. A simulation matrix is established using five vehicle types, and two mathematical models of the pedestrians represented a 50th male adult and a 6 year old child as well as seven pedestrian gaits based on typical postures in pedestrian accidents. In order to simulate a large range of impact conditions, four vehicle velocities (30 km/h, 40 km/h, 50 km/h and 60 km/h) are considered for each pedestrian position and vehicle type.A total of 43 passenger car versus pedestrian accidents were selected from In-depth Investigation of Vehicle Accidents in Changsha, China (IVAC) and German In-Depth Accident Study (GIDAS) database for simulation study. According to real-world accident investigation, accident reconstructions were conducted using multi-body system (MBS) pedestrian and car models under MADYMO simulation environment to calculate head impact conditions, in terms of head impact velocity, head position and head orientation. In order to study kinematics of adult pedestrian, relationship curves: head impact time, throw distance, head impact velocity and vehicle impact velocity, were computed and logistic regression models: head impact velocity, resultant angular velocity, HIC value, head contact force and head injuries, were developed based on the results from accident reconstructions.The automobile windshield, with which pedestrians come into frequent contact, has been identified as one of the main contact sources for pedestrian head injuries. In order to investigate the mechanical behavior of windshield laminated glass in the caseof pedestrian head impact, windshield FE models were set up using different combination for the modeling of glass and PVB, with various connection types and two mesh sizes (5 mm and 10 mm). Each windshield model was impacted with a standard adult headform impactor in an LS-DYNA simulation environment, and the results were compared with the experimental data reported in the literatures.In order to assess head injury risks of adult pedestrians, accident reconstructions were carried out by using Hybrid III head model based on the real-world pedestrian accidents. The impact conditions were obtained from the MBS simulation, including head impact velocity, head position and head orientation. They were used to set the initial conditions in a simulation of a Hybrid III FE head model striking a windshield FE model. Logistic regression models, Skull Fracture Correlate (SFC), head linear acceleration, Head Impact Power (HIP), HIC value, resultant angular acceleration and head injuries, were developed to study brain injury risk.{...]
28

Integration of V2V-AEB system with wearable cardiac monitoring system and reduction of V2V-AEB system time constraints

Bhatnagar, Shalabh January 2017 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Autonomous Emergency Braking (AEB) system uses vehicle’s on-board sensors such as radar, LIDAR, camera, infrared, etc. to detect the potential collisions, alert the driver and make safety braking decision to avoid a potential collision. Its limitation is that it requires clear line-of-sight to detect what is in front of the vehicle. Whereas, in current V2V (vehicle-to-vehicle communication) systems, vehicles communicate with each other over a wireless network and share information about their states. Thus the safety of a V2V system is limited to the vehicles with communication capabilities. Our idea is to integrate the complementary capabilities of V2V and AEB systems together to overcome the limitations of V2V and AEB systems. In a V2V-AEB system, vehicles exchange data about the objects information detected by their onboard sensors along with their locations, speeds, and movements. The object information detected by a vehicle and the information received through the V2V network is processed by the AEB system of the subject vehicle. If there is an imminent crash, the AEB system alerts the driver or applies the brake automatically in critical conditions to prevent the collision. To make V2V-AEB system advance, we have developed an intelligent heart Monitoring system and integrated it with the V2V-AEB system of the vehicle. The advancement of wearable and implantable sensors enables them to communicate driver’s health conditions with PC’s and handheld devices. Part of this thesis work concentrates on monitoring the driver’s heart status in real time by using fitness tracker. In the case of a critical health condition such as the cardiac arrest of a driver, the system informs the vehicle to take an appropriate operation decision and broadcast emergency messages over the V2V network. Thus making other vehicles and emergency services aware of the emergency condition, which can help a driver to get immediate medical attention and prevent accident casualties. To ensure that the effectiveness of the V2V-AEB system is not reduced by a time delay, it is necessary to study the effect of delay thoroughly and to handle them properly. One common practice to control the delayed vehicle trajectory information is to extrapolate trajectory to the current time. We have put forward a dynamic system that can help to reduce the effect of delay in different environments without extrapolating trajectory of the pedestrian. This method dynamically controls the AEB start braking time according to the estimated delay time in the scenario. This thesis also addresses the problem of communication overload caused by V2V-AEB system. If there are n vehicles in a V2V network and each vehicle detects m objects, the message density in the V2V network will be n*m. Processing these many messages by the receiving vehicle will take considerable computation power and cause a delay in making the braking decision. To prevent flooding of messages in V2V-AEB system, some approaches are suggested to reduce the number of messages in the V2V network that include not sending information of objects that do not cause a potential collision and grouping the object information in messages.
29

Effectiveness of Vehicle External Communication Toward Improving Vulnerable Road User Safe Behaviors: Considerations for Legacy Vehicles to Automated Vehicles of the Future

Rossi-Alvarez, Alexandria Ida 25 January 2023 (has links)
Automated vehicles (AVs) will be integrated into our society at some point in the future, but when is still up for debate. An extensive amount of research is being completed to understand the communication methods between AVs and other road users sharing the environment to prepare for this future. Currently, researchers are working to understand how different forms of external communication on the AVs will impact vulnerable road user (VRU) interaction. However, within the last 10 years, VRU casualty rates have continued to rise for all classifications of VRUs. Unfortunately, there is no suggestion that pedestrian fatality rates will ever decrease without some intervention. This dissertation aims at understanding the impacts of eHMI across real-world, complex scenarios with AVs and how researchers can apply those future findings to improve VRUs' judgments to today. A series of studies evaluated the necessity and impact of eHMI on AV–VRU interaction, assessed how the visual components of eHMI influenced VRU crossing decisions, and how variations in a real-world environment (multiple vehicles and scenario complexity) impact crossing decision behavior. Two studies examined how eHMI will impact future interactions between AVs and VRUs. Specifically, to understand how to advance the design of these future devices to avoid unintended consequences that may result. Results from these studies found that the presence and condition of eHMI did not influence participants' willingness to cross. Participants primarily relied on the speed and distance of the vehicle to make their crossing decision. It was difficult for participants to focus on the eHMI when multiple vehicles competed for their attention. Participants typically prioritized their focus on the vehicle that was nearest and most detrimental to their crossing path. Additionally, the type of scenario caused participants to make more cautious crossing decisions. However, it did not influence their willingness to cross. The last study applied the learnings from the first two studies to a foundational perception study for current legacy vehicles. These results showed a significant increase in judgment accuracies with a display. Through analysis across overall conclusions from the 3 studies, five critical findings were identified when addressing eHMI and 3 design recommendations, which are discussed in the penultimate section of this work. The results of this dissertation indicate that eHMI improved VRUs' accuracy of perception of change in vehicle speed. eHMI did not significantly impact VRUs crossing decisions. However, the complexity of the traffic scenarios affected the level of caution participants exhibited in their crossing behavior. / Doctor of Philosophy / An extensive amount of research is being completed to understand the communication methods between AVs and other road users sharing the environment to prepare for this future. Currently, researchers are working to understand how different forms of external communication on the AVs will impact vulnerable road user (VRU) interaction. However, within the last 10 years, VRU casualty rates have continued to rise for all classifications of VRUs. Unfortunately, there is no suggestion that pedestrian fatality rates will ever decrease without some intervention. This dissertation aims at understanding the impacts of eHMI across real-world, complex scenarios with AVs and how researchers can apply those future findings to improve VRUs' judgments to today. A series of studies evaluated the necessity and impact of eHMI on AV–VRU interaction, assessed how the visual components of eHMI influenced VRU crossing decisions, and how variations in a real-world environment (multiple vehicles and scenario complexity) impact crossing decision behavior.
30

Mejora del transbordo Corredor Rojo-Metro de Lima por medio de un conector peatonal en la intersección de la Av. Javier Prado con Av. Aviación / Improvement of the transhipment “Corredor Rojo”-Lima’s Metro by a pedestrian connector at the intersection of Javier Prado Avenue with Aviacion Avenue

Asenjo Albitres, Christian, Tocas Morales, Frank Anthony 19 November 2020 (has links)
La realidad peruana refleja una falta de integración de los sistemas de transporte. Asimismo, se evidencia bajos estándares de calidad con relación a las infraestructuras urbanas y una inseguridad hacia el peatón en la ciudad de Lima, un ejemplo de lo mencionado ocurre en la intersección de la Avenida Javier Prado con Aviación. Mediante el software Vissim-Visswalk 9 se realiza una microsimulación que refleja las trayectorias, frecuencias y composiciones vehiculares y peatonales, la cual se calibra y valida respectivamente. La metodología propuesta describe una delimitación de la intersección mencionada, luego se realiza la clasificación de usuarios de transportes públicos y tipos de vehículos para proceder al levantamiento de información dinámica en cuanto al aforo de vehículos y peatones y posteriormente registrarlas en el Vissim-Viswalk 9. De manera cualitativa, la seguridad vial se evalúa mediante la utilización de listas de chequeo las cuales reflejan claramente una inseguridad y alta vulnerabilidad hacia la integridad del peatón evidenciado en los 13 ítems analizados. La propuesta de solución consiste en el diseño de un conector peatonal de 320 metros, el cual cumple con los reglamentos requeridos ya que tiene un ancho efectivo constante de 1.6 metros y una pendiente máxima de 5% y 10% en el conector y en la rampa, respectivamente. Los resultados demuestran que la propuesta permite una reducción del tiempo de transbordo en un 17.1% y un aumento en la velocidad promedio de 26.1%, asimismo se evidencia un aumento significativo de la seguridad vial hacia los peatones. / Peruvian reality reflects a lack of integration of transport systems. In addition, low quality standards are evident in relation to urban infrastructures and a pedestrian insecurity in the city of Lima, an example of what is mentioned at the intersection of Avenida Javier Prado with Aviacion. The Vissim-Visswalk 9 software performs a microsimulation that reflects the trajectories, frequencies and vehicular and pedestrian compositions, which is calibrated and validated respectively. The proposed methodology describes a delimitation of the mentioned intersection, then the classification of public transport users and vehicle types is carried out to carry out dynamic information regarding the capacity of vehicles and pedestrians and subsequently register them in Vissim-Viswalk 9. Qualitatively, road safety is evaluated by using checklists which clearly reflect insecurity and high vulnerability to pedestrian integrity evident in the 13 items analyzed. The solution proposal consists of the design of a pedestrian connector of 320 meters, which complies with the required regulations since it has a constant effective width of 1.6 meters and a maximum slope of 5% and 10% on the connector and on the ramp, respectively. The results show that the proposal allows for a reduction in transfer time by 17.1% and an increase in average speed of 26.1%, and there is also a significant increase in road safety towards pedestrians. / Tesis

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