• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 198
  • 37
  • 36
  • 25
  • 25
  • 17
  • 9
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 472
  • 126
  • 120
  • 65
  • 57
  • 56
  • 51
  • 46
  • 45
  • 42
  • 42
  • 40
  • 39
  • 39
  • 31
  • 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

Methodology for Determining Crash and Injury Reduction from Emerging Crash Prevention Systems in the U.S.

Kusano, Kristofer Darwin 30 July 2013 (has links)
In order to prevent or mitigate the negative consequences of traffic crashes, automakers are developing active safety systems, which aim to prevent or mitigate collisions.  These systems are expensive to develop and as a result automakers and regulators are motivated to forecast the potential benefits of a proposed safety system before it is widely deployed in the vehicle fleet. The objective of this dissertation was to develop a methodology for predicting fleet-wide benefits for emerging crash avoidance systems as if all vehicles were equipped with a system.  Forward Collision Avoidance Systems (FCAS) were used as an example application of this methodology. The methodology developed for this research includes the following components: 1) identification of the target population, 2) development and validation of a driver model, 3) development of injury risk functions, 4) development of a crash severity reduction model, and 5) computation of fleet-wide benefits.  This dissertation presents a general methodology for each of these components that could be used for any active safety system.  Then a specific model is constructed for FCAS. FCAS could potentially be applicable to 31% of all collisions, 6% of serious injury crashes, and 7% of fatal crashes.  Annually, this accounts for 3.3 million collisions and 18,367 fatal crashes.  We developed a model of driver braking in response to a forward collision warning. Next we used logistic regression to develop injury risk functions that predicted the probability of injury given the crash severity ("V) and occupant characteristics.  Finally, we simulated 2,459 real-world rear-end collisions as if the driver had an FCAS with combinations of warnings, brake assist, and autonomous braking.  We found that between 3.4% and 7.2% of crashes could be prevented and that many more could be mitigated in severity.  These systems reduced the number of injured (MAIS2+) drivers in rear-end collisions between 32% and 55%.  In total, the systems could prevent between $184 and $338 million in economic costs associated with crashes per year. / Ph. D.
12

MODELING BASE CRASH RATES FOR INTERSECTIONS

KASHAYI, NAGARAJU C. January 2006 (has links)
No description available.
13

From Crash to Care:  A Road Towards Improved Safety and Efficiency of Emergency Medical Response

Valente, Jacob Tyler 05 January 2024 (has links)
Motor vehicle crashes (MVCs) are a global public health concern. In 2020 alone, there were an estimated 6.76 million police reported crashes in the United States [1]. In the wake of an MVC, those involved may have been inflicted with serious or fatal injuries. Despite large research and development efforts to design vehicles and safety features to help reduce the frequency and severity of MVCs, crashes are, and will continue to be, a reality. In response to MVCs, first responders are tasked to provide crash victims with rapid immediate care and transport them to an appropriate facility. In spite of continued progress in emergency medicine, there are still many operational hurdles that emergency medical technicians need to overcome to perform their duties proficiently. Development and deployment of advanced automatic crash notification (AACN) systems have the potential to reduce the time between a crash and 911 system activation, especially for unseen roadway departures or crashes that render occupants incapacitated. Ultimately, AACN systems may aid first responders and improve MVC patient outcomes, however, these systems only target the earliest elements of an emergency response event. Therefore, the work contained in this dissertation aimed to identify additional areas for improvement within an emergency response event, specifically MVCs, and propose and/or develop solutions to address them. The first area pertained to emergency medical services (EMS) transportation, which can include responding to and transporting patients from an MVC. Through the analysis of the national EMS Information System database, an existing light vehicle naturalistic driving study, and a pilot ambulance-based naturalistic driving study, this dissertation provides a comprehensive investigation into EMS roadway interactions. The findings of these investigations confirmed that traffic interactions are a common issue and leading cause of EMS delay during response and transport phases. Even when ambulance operators drive with observed "due regard" and utilize emergency lights and sirens appropriate, many drivers were observed to yield the right of way inappropriately or in a delayed manner that resulted in safety critical events on open roadways and in intersections. The second area of improvement pertained to providing EMS with detailed patient information following an MVC. This took shape through the development of a post-crash injury triage system that provides first responders with occupant condition prior to on-scene arrival. The proposed system collects and shares crash occupant respiration rate, heart rate, and mental status through vehicle cabin integrated sensors and a post-crash response operator. This information, and additional vehicle specific crash details, are then populated into post-crash web application that responding agencies can view and interact with to strategically allocate response resources and predevelop transportation plans. Collectively, the work included in this dissertation identified challenges that EMS face when responding to MVCs, and produced findings that can be used to develop technology, update policies, and innovate in the transportation sector to improve emergency response and post-crash care. The identified safety and efficiency benefits not only apply to emergency respondents but encompass benefits to crash victims and all other road users. Although targeted at MVCs, the findings of this dissertation may also be applicable to many different types of emergencies and can benefit other public safety domains such as law enforcement, fire services, towing, and infrastructure maintenance. / Doctor of Philosophy / Motor vehicle crashes (MVCs) are a global public health concern. In 2020 alone, there were an estimated 6.76 million police reported crashes in the United States [1]. In the wake of an MVC, those involved may have been seriously or fatally injuries. Despite large research and development efforts to design vehicles and safety features to help reduce the frequency and severity of MVCs, crashes are, and will continue to be, a reality. In response to MVCs, first responders are tasked to provide crash victims with rapid immediate care and transport them to an appropriate facility. In spite of continued progress in emergency medicine, there are still many operational hurdles that emergency medical technicians need to overcome to perform their duties proficiently. Development and deployment of advanced automatic crash notification (AACN) systems have the potential to reduce the time between a crash when a 911 response is started, especially for unseen roadway departures or crashes that render occupants incapacitated. Ultimately, AACN systems may aid first responders and improve MVC patient outcomes, however, these systems only target the earliest elements of an emergency response event. Therefore, the work contained in this dissertation aimed to identify additional areas for improvement within an emergency response event, specifically MVCs, and propose and/or develop solutions to address them. The first area pertained to emergency medical services (EMS) transportation, which can include responding to and transporting patients from an MVC. Through the analysis of a national database, an existing light vehicle driving study, and a pilot ambulance-based driving study, this dissertation provides a comprehensive investigation into EMS roadway interactions. The findings can be used to better understand EMS roadway interactions and applied to develop innovative ways to improve safety and efficiency for all road users. The second area of improvement pertained to providing EMS with detailed patient information following an MVC. This took shape through the development of a post-crash injury triage system that provides first responders with occupant condition prior to on-scene arrival. The proposed system collects and shares crash occupant respiration rate, heart rate, and mental status, allowing responding agencies to strategically allocate response resources and predevelop transportation plans. Collectively, the work included in this dissertation identified challenges that EMS face when responding to MVCs, and produced findings that can be used to develop technology, update policies, and innovate in the transportation sector to improve emergency response and post-crash care. The identified safety and efficiency benefits not only apply to emergency respondents but encompass benefits to crash victims and all other road users. Although targeted at MVCs, the findings of this dissertation may also be applicable to many different types of emergencies and can benefit other public safety domains such as law enforcement, fire services, towing, and infrastructure maintenance. Therefore, the work contained in this dissertation aimed to identify additional areas for improvement within an emergency response event, specifically MVCs, and propose and/or develop solutions to address them. The first area pertained to emergency medical services (EMS) transportation, which can include responding to and transporting patients from an MVC. Through the analysis of a national database, an existing light vehicle naturalistic driving study, and a pilot ambulance-based naturalistic driving study, this dissertation provides a comprehensive investigation into EMS roadway interactions. The findings can be used to better understand EMS roadway interactions and applied to develop innovative ways to improve safety and efficiency for all road users. The second area of improvement pertained to providing EMS with detailed patient information following an MVC. This took shape through the development of a post-crash injury triage system that provides first responders with occupant condition prior to on-scene arrival. The proposed system collects and shares crash occupant respiration rate, heart rate, and mental status, allowing responding agencies to strategically allocate response resources and predevelop transportation plans. Collectively, the work included in this dissertation identified challenges that EMS face when responding to MVCs, and produced findings that can be used to develop technology, update policies, and innovate in the transportation sector to improve emergency response and post-crash care. The identified safety and efficiency benefits not only apply to emergency respondents but encompass benefits to crash victims and all other road users. Although targeted at MVCs, the findings of this dissertation may also be applicable to many different types of emergencies and can benefit other public safety domains such as law enforcement, fire services, towing, and infrastructure maintenance.
14

Twisted Metal: An Investigation into Observable Factors that Lead to Critical Traffic Events

Kieliszewski, Cheryl A. 09 December 2005 (has links)
The purpose of this research was to explore traffic event severity relationships, evaluate the potentiality of a hazardous event, and develop a framework of observable event factors. Data was collected from three regions in Virginia, each assumed to exemplify a unique driving environment due to amount of traffic and infrastructure characteristics. In combination, a broad spectrum of site, traffic, and driver performance variables were accounted for. Observational techniques of surveillance, incident reporting, and inventorying were used to collect site, traffic, and driver data. This effort resulted in 368 observed traffic events that were evenly distributed among the three regions that represented metropolitan, mid-sized city, and town/rural driving environments. The 368 events were evaluated for severity and contributing variables where 1% of the events were non-injury crashes, 10% were serious, near-crashes, 24% were near-crashes, and the remaining 65% were serious errors with a hazard present. Exploratory analyses were performed to understand the general relationship between event severity levels. Binary logistic regression analyses (α = 0.05) were performed to further scope predictor variables to identify traffic event characteristics with respect to severity level, maneuver type, and conflict type. The results were that 69 of 162 observed predictor variables were valuable in characterizing traffic events based on severity. It was found that variables could be grouped to create event severity signatures for crashes, serious near-crashes, and near-crashes. Based on these signatures, it was found that there is a trend between severity levels that included a propensity for problems with straight path maneuvers, lateral and longitudinal vehicle control, and information density within the driving environment as contributing to driver error and hence crashes and near-crashes. There were also differences between the severity levels. These differences were evident in the degree of control the driver appeared to have of the vehicle, type of control regulating the driving environment, and type of road users present in the driving environment. Modifications to roadway evaluative techniques would increase awareness of additional variables that impact drivers to make more informed decisions for roadway enhancements. / Ph. D.
15

The Crash Injury Risk to Rear Seated Passenger Vehicle Occupants

Tatem, Whitney M. 22 January 2020 (has links)
Historically, rear seat occupants have been at a lower risk of serious injury and fatality in motor vehicle crashes than their front seat counterparts. However, many passive safety advancements that have occurred over the past few decades such as advanced airbag and seatbelt technology primarily benefit occupants of the front seat. Indeed, safety for front seat occupants has improved drastically in the 21st century, but has it improved so much that the front seat is now safer than the rear? Today, rear-seated occupants account for 10% of all passenger vehicle fatalities. In this era focused on achieving zero traffic deaths, the safety of rear-seated occupants must be further addressed. This dissertation analyzed U.S. national crash data to quantify the risk of injury and fatality to rear-seated passenger vehicle occupants while accounting for the influence of associated crash, vehicle, and occupant characteristics such as crash severity, vehicle model year, and occupant age/sex. In rear impacts, the risk of moderate-to-fatal injury was greater for rear-seated occupants than their front-seated counterparts. In high-severity rear impact crashes, catastrophic occupant compartment collapse can occur and carries with it a great fatality risk. In frontal impacts, there is evidence that the rear versus front seat relative risk of fatality has been increasing in vehicle model years 2007 and newer. Rear-seated occupants often sustained serious thoracic, abdomen, and/or head injuries that are generally related to seatbelt use. Seatbelt pretensioners and load limiters – commonplace technology in the front seating positions – aim to mitigate these types of injuries but are rarely provided as standard safety equipment in the rear seats of vehicles today. Finally, in side impacts, injury and fatality risks to rear- and front-seated occupants are more similar than in the other crash modes studied, though disparities in protection remain, especially in near-side vehicle-to-vehicle crashes. Finally, this work projects great injury reduction benefits if a rear seat belt reminder system were to be widely implemented in the U.S. vehicle fleet. This dissertation presents a comprehensive investigation of the factors that contribute to rear-seated occupant injury and/or fatality through retrospective studies on rear, front, and side impacts. The overall goal of this dissertation is to better quantify the current risk of injury to rear-seated occupants under a variety of crash conditions, compare this to the current risk to front-seated occupants, and, when possible, identify how exactly injuries are occurring and ways in which they may be prevented in the future. The findings can benefit automakers who seek to improve the effectiveness of rear seat safety systems as well as regulatory agencies seeking to improve was vehicle tests targeting rear seat passenger vehicle safety. / Doctor of Philosophy / Historically, if a passenger vehicle such as a sedan or SUV is in a crash, occupants who are rear-seated were less likely to be hurt than someone who was front-seated. In other words, rear-seated occupants have been at a lower risk of injury than front-seated occupants. Indeed, safety for front seat occupants has improved drastically in the 21st century due to advancements in airbag and seatbelt technologies, among others, but has it improved so much that the front seat is now safer than the rear? Today, of all vehicle occupants who are killed in crashes on U.S. roadways, 10% are rear-seated. During this time when conversations surrounding vehicle safety are focused on achieving zero traffic deaths, the safety of rear-seated occupants must be further studied. This dissertation looked at national databases of all police-reported crashes that occur each year in the United States. The risk of injury to rear-seated passenger vehicle occupants was quantified and compared to that of front-seated occupants. Factors that may increase or decrease this risk of injury and fatality such as crash type, vehicle type, and occupant demographics were further explored and reported. In vehicles that were rear-ended, the risk of injury was greater for rear-seated occupants than their front-seated counterparts. When a vehicle crashes into something front-first (the most common type of impact in a vehicle crash), evidence is presented that the risk of fatality is greater in the rear seats than the front seats in model year 2007 and newer vehicles which generally are equipped with the most recent airbag and seatbelt technology. When a vehicle is hit on either of its sides, the risk of injury is closer between rear- and front-seated occupants than it was in the rear-end or frontal crashes previously studied. That said, differences in occupant protection were still observed between the rear and front seats, especially when the occupants studied were seated on the closest side of impact, or the near-side, and the vehicle was struck by another vehicle rather than sliding into an object such as a pole. Finally, this work projects great injury reduction benefits if a rear seat belt reminder system were to be widely implemented in the U.S. vehicle fleet. This dissertation presents a comprehensive investigation of the factors that contribute to rear-seated occupant injury and/or fatality through retrospective studies on rear, front, and side impacts. The overall goal of this dissertation is to better quantify the current risk of injury to rear-seated occupants under a variety of crash conditions, compare this to the current risk to front-seated occupants, and, when possible, identify how exactly injuries are occurring and ways in which they may be prevented in the future. The findings can benefit automakers who seek to improve the effectiveness of rear seat safety systems as well as regulatory agencies seeking to improve was vehicle tests targeting rear seat passenger vehicle safety.
16

A feasibility study for an optimising algorithm to guide car structure design under side impact loading

Harle, Nick January 1998 (has links)
No description available.
17

Maxillofacial, chest and abdominal injuries sustained in severe traffic accidents

Arajärvi, Eero. January 1989 (has links)
Thesis--Helsinki University, 1989. / Includes bibliographical references (p. 50-55).
18

Anpassung des CrashViewers zur immersiven Visualisierung

Piekarski, Thomas. January 2001 (has links)
Stuttgart, Univ., Fakultät Informatik, Studienarbeit, 2001.
19

Qualitative und quantitative Bewertung der Crashtauglichkeit von höchstfesten Stählen /

Laumann, Till. January 2010 (has links)
Zugl.: Erlangen-Nürnberg, Universiẗat, Diss., 2009.
20

Energy as a basis for accident severity a preliminary study /

Campbell, Kenneth L. January 1972 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1972. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Page generated in 0.0414 seconds