Braking News: the Link between Crash Severity and Crash Avoidance Maneuvers

DEFF Research Database (Denmark)

Kaplan, Sigal; Prato, Carlo Giacomo

2012-01-01

the ordered-response nature of severity while allowing for changes in effects across severity levels. The data sample for estimation consists of single-vehicle crashes extracted from the General Estimates System (GES) crash database for the period 2005-2009. Results show the correlation between crash...... severity. These trends suggest that effort should be posed toward understanding the reaction mechanisms to different critical events, improving in-vehicle warning systems, promoting responsible driving behavior, and designing forgiving infrastructures....

A test-based method for the assessment of pre-crash warning and braking systems.

Science.gov (United States)

Bálint, András; Fagerlind, Helen; Kullgren, Anders

2013-10-01

In this paper, a test-based assessment method for pre-crash warning and braking systems is presented where the effectiveness of a system is measured by its ability to reduce the number of injuries of a given type or severity in car-to-car rear-end collisions. Injuries with whiplash symptoms lasting longer than 1 month and MAIS2+ injuries in both vehicles involved in the crash are considered in the assessment. The injury reduction resulting from the impact speed reduction due to a pre-crash system is estimated using a method which has its roots in the dose-response model. Human-machine interaction is also taken into account in the assessment. The results reflect the self-protection as well as the partner-protection performance of a pre-crash system in the striking vehicle in rear-end collisions and enable a comparison between two or more systems. It is also shown how the method may be used to assess the importance of warning as part of a pre-crash system. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effectiveness of antilock braking systems in reducing motorcycle fatal crash rates.

Science.gov (United States)

Teoh, Eric R

2011-04-01

Overbraking and underbraking have been shown to be common factors in motorcycle crashes. Antilock braking systems (ABS) prevent wheels from locking during braking and may make riders less reluctant to apply full braking force. The objective of this study was to evaluate the effect of ABS in fatal motorcycle crashes. Motorcycle drivers involved in fatal crashes per 10,000 registered vehicle years were compared for 13 motorcycle models with optional ABS and those same models without the option during 2003-2008. Motorcycles with optional ABS were included only if the presence of the option could be identified from the vehicle identification number. The rate of fatal motorcycle crashes per 10,000 registered vehicle years was 37 percent lower for ABS models than for their non-ABS versions. ABS appears to be highly effective in preventing fatal motorcycle crashes based on some early adopters of motorcycle ABS technology.

Requirements of a system to reduce car-to-vulnerable road user crashes in urban intersections.

Science.gov (United States)

Habibovic, Azra; Davidsson, Johan

2011-07-01

Intersection crashes between cars and vulnerable road users (VRUs), such as pedestrians and bicyclists, often result in injuries and fatalities. Advanced driver assistance systems (ADASs) can prevent, or mitigate, these crashes. To derive functional requirements for such systems, an understanding of the underlying contributing factors and the context in which the crashes occur is essential. The aim of this study is to use microscopic and macroscopic crash data to explore the potential of information and warning providing ADASs, and then to derive functional sensor, collision detection, and human-machine interface (HMI) requirements. The microscopic data were obtained from the European project SafetyNet. Causation charts describing contributing factors for 60 car-to-VRU crashes had been compiled and were then also aggregated using the SafetyNet Accident Causation System (SNACS). The macroscopic data were obtained from the Swedish national crash database, STRADA. A total of 9702 crashes were analyzed. The results show that the most frequent contributing factor to the crashes was the drivers' failure to observe VRUs due to reduced visibility, reduced awareness, and/or insufficient comprehension. An ADAS should therefore help drivers to observe the VRUs in time and to enhance their ability to interpret the development of events in the near future. The system should include a combination of imminent and cautionary collision warnings, with additional support in the form of information about intersection geometry and traffic regulations. The warnings should be deployed via an in-vehicle HMI and according to the likelihood of crash risk. The system should be able to operate under a variety of weather and light conditions. It should have the capacity to support drivers when their view is obstructed by physical objects. To address problems that vehicle-based sensors may face in this regard, the use of cooperative systems is recommended. Copyright © 2011 Elsevier Ltd. All

Estimating Motor Carrier Management Information System Crash File Underreporting from Carrier Records.

Science.gov (United States)

2017-08-01

This FMCSA-sponsored research investigated the claim that motor carriers have a substantial number of crashes in their own records that are not contained in the Motor Carrier Management Information System (MCMIS) crash file. Based on the results of t...

The effectiveness of lane departure warning systems-A reduction in real-world passenger car injury crashes.

Science.gov (United States)

Sternlund, Simon; Strandroth, Johan; Rizzi, Matteo; Lie, Anders; Tingvall, Claes

2017-02-17

The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes. The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems. The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions). LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers.

Effectiveness of forward collision warning and autonomous emergency braking systems in reducing front-to-rear crash rates.

Science.gov (United States)

Cicchino, Jessica B

2017-02-01

The objective of this study was to evaluate the effectiveness of forward collision warning (FCW) alone, a low-speed autonomous emergency braking (AEB) system operational at speeds up to 19mph that does not warn the driver prior to braking, and FCW with AEB that operates at higher speeds in reducing front-to-rear crashes and injuries. Poisson regression was used to compare rates of police-reported crash involvements per insured vehicle year in 22 U.S. states during 2010-2014 between passenger vehicle models with FCW alone or with AEB and the same models where the optional systems were not purchased, controlling for other factors affecting crash risk. Similar analyses compared rates between Volvo 2011-2012 model S60 and 2010-2012 model XC60 vehicles with a standard low-speed AEB system to those of other luxury midsize cars and SUVs, respectively, without the system. FCW alone, low-speed AEB, and FCW with AEB reduced rear-end striking crash involvement rates by 27%, 43%, and 50%, respectively. Rates of rear-end striking crash involvements with injuries were reduced by 20%, 45%, and 56%, respectively, by FCW alone, low-speed AEB, and FCW with AEB, and rates of rear-end striking crash involvements with third-party injuries were reduced by 18%, 44%, and 59%, respectively. Reductions in rear-end striking crashes with third-party injuries were marginally significant for FCW alone, and all other reductions were statistically significant. FCW alone and low-speed AEB reduced rates of being rear struck in rear-end crashes by 13% and 12%, respectively, but FCW with AEB increased rates of rear-end struck crash involvements by 20%. Almost 1 million U.S. police-reported rear-end crashes in 2014 and more than 400,000 injuries in such crashes could have been prevented if all vehicles were equipped with FCW and AEB that perform similarly as systems did for study vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crash protection of stock car racing drivers--application of biomechanical analysis of Indy car crash research.

Science.gov (United States)

Melvin, John W; Begeman, Paul C; Faller, Ronald K; Sicking, Dean L; McClellan, Scott B; Maynard, Edwin; Donegan, Michael W; Mallott, Annette M; Gideon, Thomas W

2006-11-01

Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars. Unlike the Indy car, the typical racing stock car features a more spacious driver cockpit due to its resemblance to the shape of a passenger car. The typical racing seat used in stock cars did not have the same configuration or support characteristics of the Indy car seat, and five-point belt restraints were used. The tubular steel space frame chassis of a stock car also differs from an Indy car's composite chassis structure in both form and mechanical behavior. This paper describes the application of results of the biomechanical analysis of the Indy car crash studies to the unique requirements of stock car racing driver crash protection. Sled test and full-scale crash test data using both Hybrid III frontal crash anthropomorphic test devices (ATDs) and BioSID side crash ATDs for the purpose of evaluating countermeasures involving restraint systems, seats and head/neck restraints has been instrumental in guiding these developments. In addition, the development of deformable walls for oval tracks (the SAFER Barrier) is described as an adjunct to improved occupant restraint through control

Connected motorcycle crash warning interfaces.

Science.gov (United States)

2016-01-15

Crash warning systems have been deployed in the high-end vehicle market segment for some time and are trickling down to additional motor vehicle industry segments each year. The motorcycle segment, however, has no deployed crash warning system to dat...

Estimating likelihood of future crashes for crash-prone drivers

Directory of Open Access Journals (Sweden)

Subasish Das

2015-06-01

Full Text Available At-fault crash-prone drivers are usually considered as the high risk group for possible future incidents or crashes. In Louisiana, 34% of crashes are repeatedly committed by the at-fault crash-prone drivers who represent only 5% of the total licensed drivers in the state. This research has conducted an exploratory data analysis based on the driver faultiness and proneness. The objective of this study is to develop a crash prediction model to estimate the likelihood of future crashes for the at-fault drivers. The logistic regression method is used by employing eight years' traffic crash data (2004–2011 in Louisiana. Crash predictors such as the driver's crash involvement, crash and road characteristics, human factors, collision type, and environmental factors are considered in the model. The at-fault and not-at-fault status of the crashes are used as the response variable. The developed model has identified a few important variables, and is used to correctly classify at-fault crashes up to 62.40% with a specificity of 77.25%. This model can identify as many as 62.40% of the crash incidence of at-fault drivers in the upcoming year. Traffic agencies can use the model for monitoring the performance of an at-fault crash-prone drivers and making roadway improvements meant to reduce crash proneness. From the findings, it is recommended that crash-prone drivers should be targeted for special safety programs regularly through education and regulations.

Impact of pavement conditions on crash severity.

Science.gov (United States)

Li, Yingfeng; Liu, Chunxiao; Ding, Liang

2013-10-01

Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of Expected Crash and Injury Reduction from Production Forward Collision and Lane Departure Warning Systems.

Science.gov (United States)

Kusano, Kristofer D; Gabler, Hampton C

2015-01-01

The U.S. New Car Assessment Program (NCAP) now tests for forward collision warning (FCW) and lane departure warning (LDW). The design of these warnings differs greatly between vehicles and can result in different real-world field performance in preventing or mitigating the effects of collisions. The objective of this study was to compare the expected number of crashes and injured drivers that could be prevented if all vehicles in the fleet were equipped with the FCW and LDW systems tested under the U.S. NCAP. To predict the potential crashes and serious injury that could be prevented, our approach was to computationally model the U.S. crash population. The models simulated all rear-end and single-vehicle road departure collisions that occurred in a nationally representative crash database (NASS-CDS). A sample of 478 single-vehicle crashes from NASS-CDS 2012 was the basis for 24,822 simulations for LDW. A sample of 1,042 rear-end collisions from NASS-CDS years 1997-2013 was the basis for 7,616 simulations for FCW. For each crash, 2 simulations were performed: (1) without the system present and (2) with the system present. Models of each production safety system were based on 54 model year 2010-2014 vehicles that were evaluated under the NCAP confirmation procedure for LDW and/or FCW. NCAP performed 40 LDW and 45 FCW tests of these vehicles. The design of the FCW systems had a dramatic impact on their potential to prevent crashes and injuries. Between 0 and 67% of crashes and 2 and 69% of moderately to fatally injured drivers in rear-end impacts could have been prevented if all vehicles were equipped with the FCW systems. Earlier warning times resulted in increased benefits. The largest effect on benefits, however, was the lower operating speed threshold of the systems. Systems that only operated at speeds above 20 mph were less than half as effective as those that operated above 5 mph with similar warning times. The production LDW systems could have prevented

Injury mitigation estimates for an intersection driver assistance system in straight crossing path crashes in the United States.

Science.gov (United States)

Scanlon, John M; Sherony, Rini; Gabler, Hampton C

2017-05-29

Accounting for one fifth of all crashes and one sixth of all fatal crashes in the United States, intersection crashes are among the most frequent and fatal crash modes. Intersection advanced driver assistance systems (I-ADAS) are emerging vehicle-based active safety systems that aim to help drivers safely navigate intersections. The objective of this study was to estimate the number of crashes and number of vehicles with a seriously injured driver (Maximum Abbreviated Injury Scale [MAIS] 3+) that could be prevented or reduced if, for every straight crossing path (SCP) intersection crash, one of the vehicles had been equipped with an I-ADAS. This study retrospectively simulated 448 U.S. SCP crashes as if one of the vehicles had been equipped with I-ADAS. Crashes were reconstructed to determine the path and speeds traveled by the vehicles. Cases were then simulated with I-ADAS. A total of 30 variations of I-ADAS were considered in this study. These variations consisted of 5 separate activation timing thresholds, 3 separate computational latency times, and 2 different I-ADAS response modalities (i.e., a warning or autonomous braking). The likelihood of a serious driver injury was computed for every vehicle in every crash using impact delta-V. The results were then compiled across all crashes in order to estimate system effectiveness. The model predicted that an I-ADAS that delivers an alert to the driver has the potential to prevent 0-23% of SCP crashes and 0-25% of vehicles with a seriously injured driver. Conversely, an I-ADAS that autonomously brakes was found to have the potential to prevent 25-59% of crashes and 38-79% of vehicles with a seriously injured driver. I-ADAS effectiveness is a strong function of design. Increasing computational latency time from 0 to 0.5 s was found to reduce crash and injury prevention estimates by approximately one third. For an I-ADAS that delivers an alert, crash/injury prevention effectiveness was found to be very sensitive to

A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

DEFF Research Database (Denmark)

Kaplan, Sigal; Prato, Carlo Giacomo

' propensity to engage in various corrective maneuvers in the case of the critical event of vehicle travelling. Five lateral and speed control maneuvers are considered: “braking”, “steering”, “braking & steering”, and “other maneuvers”, in addition to a “no action” option. The analyzed data are retrieved from...... the United States National Automotive Sampling System General Estimates System (GES) crash database for the years 2005-2009. Results show (i) the correlation between crash avoidance maneuvers and crash severity, and (ii) the link between drivers' attributes, risky driving behavior, road characteristics...

Evaluation of the crash mitigation effect of low-speed automated emergency braking systems based on insurance claims data.

Science.gov (United States)

Isaksson-Hellman, Irene; Lindman, Magdalena

2016-09-01

The aim of the present study was to evaluate the crash mitigation performance of low-speed automated emergency braking collision avoidance technologies by examining crash rates, car damage, and personal injuries. Insurance claims data were used to identify rear-end frontal collisions, the specific situations where the low-speed automated emergency braking system intervenes. We compared cars of the same model (Volvo V70) with and without the low-speed automated emergency braking system (AEB and no AEB, respectively). Distributions of spare parts required for car repair were analyzed to identify car damage, and crash severity was estimated by comparing the results with laboratory crash tests. Repair costs and occupant injuries were investigated for both the striking and the struck vehicle. Rear-end frontal collisions were reduced by 27% for cars with low-speed AEB compared to cars without the system. Those of low severity were reduced by 37%, though more severe crashes were not reduced. Accordingly, the number of injured occupants in vehicles struck by low-speed AEB cars was reduced in low-severity crashes. In offset crash configurations, the system was found to be less effective. This study adds important information about the safety performance of collision avoidance technologies, beyond the number of crashes avoided. By combining insurance claims data and information from spare parts used, the study demonstrates a mitigating effect of low-speed AEB in real-world traffic.

Estimating likelihood of future crashes for crash-prone drivers

OpenAIRE

Subasish Das; Xiaoduan Sun; Fan Wang; Charles Leboeuf

2015-01-01

At-fault crash-prone drivers are usually considered as the high risk group for possible future incidents or crashes. In Louisiana, 34% of crashes are repeatedly committed by the at-fault crash-prone drivers who represent only 5% of the total licensed drivers in the state. This research has conducted an exploratory data analysis based on the driver faultiness and proneness. The objective of this study is to develop a crash prediction model to estimate the likelihood of future crashes for the a...

The Influence of Manufacturing Variations on a Crash Energy Management System

Science.gov (United States)

2008-09-24

Crash Energy Management (CEM) systems protect passengers in the event of a train collision. A CEM system distributes crush throughout designated unoccupied crush zones of a passenger rail consist. This paper examines the influence of manufacturing va...

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

Science.gov (United States)

2011-01-01

Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102 PMID:21291517

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

Directory of Open Access Journals (Sweden)

Roberts Ian

2011-02-01

Full Text Available Abstract Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials, quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions, whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions. Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102

Robust client/server shared state interactions of collaborative process with system crash and network failures

NARCIS (Netherlands)

Wang, Lei; Wombacher, Andreas; Ferreira Pires, Luis; van Sinderen, Marten J.; Chi, Chihung

With the possibility of system crashes and network failures, the design of robust client/server interactions for collaborative process execution is a challenge. If a business process changes state, it sends messages to relevant processes to inform about this change. However, server crashes and

Effectiveness of motorcycle antilock braking systems (ABS) in reducing crashes, the first cross-national study.

Science.gov (United States)

Rizzi, Matteo; Strandroth, Johan; Kullgren, Anders; Tingvall, Claes; Fildes, Brian

2015-01-01

This study set out to evaluate the effectiveness of motorcycle antilock braking systems (ABS) in reducing real-life crashes. Since the European Parliament has voted on legislation making ABS mandatory on all new motorcycles over 125 cc from 2016, the fitment rate in Europe is likely to increase in the coming years. Though previous research has focused on mostly large displacement motorcycles, this study used police reports from Spain (2006-2009), Italy (2009), and Sweden (2003-2012) in order to analyze a wide range of motorcycles, including scooters, and compare countries with different motorcycling habits. The statistical analysis used odds ratio calculations with an induced exposure approach. Previous research found that head-on crashes were the least ABS-affected crash type and was therefore used as the nonsensitive crash type for ABS in these calculations. The same motorcycle models, with and without ABS, were compared and the calculations were carried out for each country separately. Crashes involving only scooters were further analyzed. The effectiveness of motorcycle ABS in reducing injury crashes ranged from 24% (95% confidence interval [CI], 12-36) in Italy to 29% (95% CI, 20-38) in Spain, and 34% (95% CI, 16-52) in Sweden. The reductions in severe and fatal crashes were even greater, at 34% (95% CI, 24-44) in Spain and 42% (95% CI, 23-61) in Sweden. The overall reductions of crashes involving ABS-equipped scooters (at least 250 cc) were 27% (95% CI, 12-42) in Italy and 22% (95% CI, 2-42) in Spain. ABS on scooters with at least a 250 cc engine reduced severe and fatal crashes by 31% (95% CI, 12-50), based on Spanish data alone. At this stage, there is more than sufficient scientific-based evidence to support the implementation of ABS on all motorcycles, even light ones. Further research should aim at understanding the injury mitigating effects of motorcycle ABS, possibly in combination with combined braking systems.

The TUeV Bayern's ECV crash system. Das ECV-Crashsystem des TUeV Bayern

Energy Technology Data Exchange (ETDEWEB)

Hupfer, P.; Richter, R.; Wech, L.

1992-05-01

In order to obtain more realistic crash test results, TUeV Bayern has developed the ECV Crash Technology (Eletronically Controlled Vehicle), in which the vehicle is driven by its own engine and automatically steered. Further advantages of this system are the high precision and flexibility of the crash configuration and its mobility. The driverless operation of the vehicle is realized by a microprocessor-equiped control unit, which activates steering system, throttle, brake and clutch. The desired course of the vehicle is predetermined by the pilot cable. Through this cable low frequency alternating current is flowing. (orig./HW).

Barrier-relevant crash modification factors and average costs of crashes on arterial roads in Indiana.

Science.gov (United States)

Zou, Yaotian; Tarko, Andrew P

2018-02-01

The objective of this study was to develop crash modification factors (CMFs) and estimate the average crash costs applicable to a wide range of road-barrier scenarios that involved three types of road barriers (concrete barriers, W-beam guardrails, and high-tension cable barriers) to produce a suitable basis for comparing barrier-oriented design alternatives and road improvements. The intention was to perform the most comprehensive and in-depth analysis allowed by the cross-sectional method and the crash data available in Indiana. To accomplish this objective and to use the available data efficiently, the effects of barrier were estimated on the frequency of barrier-relevant (BR) crashes, the types of harmful events and their occurrence during a BR crash, and the severity of BR crash outcomes. The harmful events component added depth to the analysis by connecting the crash onset with its outcome. Further improvement of the analysis was accomplished by considering the crash outcome severity of all the individuals involved in a crash and not just drivers, utilizing hospital data, and pairing the observations with and without road barriers along same or similar road segments to better control the unobserved heterogeneity. This study confirmed that the total number of BR crashes tended to be higher where medians had installed barriers, mainly due to collisions with barriers and, in some cases, with other vehicles after redirecting vehicles back to traffic. These undesirable effects of barriers were surpassed by the positive results of reducing cross-median crashes, rollover events, and collisions with roadside hazards. The average cost of a crash (unit cost) was reduced by 50% with cable barriers installed in medians wider than 50ft. A similar effect was concluded for concrete barriers and guardrails installed in medians narrower than 50ft. The studied roadside guardrails also reduced the unit cost by 20%-30%. Median cable barriers were found to be the most effective

"Crashing the gates" - selection criteria for television news reporting of traffic crashes.

Science.gov (United States)

De Ceunynck, Tim; De Smedt, Julie; Daniels, Stijn; Wouters, Ruud; Baets, Michèle

2015-07-01

This study investigates which crash characteristics influence the probability that the crash is reported in the television news. To this purpose, all news items from the period 2006-2012 about traffic crashes from the prime time news of two Belgian television channels are linked to the official injury crash database. Logistic regression models are built for the database of all injury crashes and for the subset of fatal crashes to identify crash characteristics that correlate with a lower or higher probability of being reported in the news. A number of significant biases in terms of crash severity, time, place, types of involved road users and victims' personal characteristics are found in the media reporting of crashes. More severe crashes are reported in the media more easily than less severe crashes. Significant fluctuations in media reporting probability through time are found in terms of the year and month in which the crash took place. Crashes during week days are generally less reported in the news. The geographical area (province) in which the crash takes place also has a significant impact on the probability of being reported in the news. Crashes on motorways are significantly more represented in the news. Regarding the age of the involved victims, a clear trend of higher media reporting rates of crashes involving young victims or young fatalities is observed. Crashes involving female fatalities are also more frequently reported in the news. Furthermore, crashes involving a bus have a significantly higher probability of being reported in the news, while crashes involving a motorcycle have a significantly lower probability. Some models also indicate a lower reporting rate of crashes involving a moped, and a higher reporting rate of crashes involving heavy goods vehicles. These biases in media reporting can create skewed perceptions in the general public about the prevalence of traffic crashes and eventually may influence people's behaviour. Copyright © 2015

Modeling wrong-way crashes and fatalities on arterials and freeways

Directory of Open Access Journals (Sweden)

Raj V. Ponnaluri

2018-04-01

Full Text Available Wrong way driving (WWD research and mitigation measures have primarily focused on limited access facilities. This is most likely due to the higher incidence of fatal WWD crashes with dramatic consequences on freeways, media attention, and a call for innovative solutions to address the problem. While public agencies and published literature address WWD incidence on freeway systems, the crash analyses on non-limited access facilities, i.e., arterial corridors, remains untouched. This research extends previous works and attempts to provide many new perspectives on arterial WWD incidence. In particular, one work showed that while WWD fatalities are more likely to occur on freeways, the likelihood of these crashes is higher on arterials. Hence this work with univariate and multivariate analyses of WWD and non-WWD crashes, and fatal and non-fatal WWD incidents. Results show the impressive negative impacts of alcohol use, driver defect, nighttime and weekend incidence, poor street lighting, low traffic volumes, rural geography, and median and shoulder widths. The objective here is to highlight the need for paying greater attention to WWD crashes on arterial corridors as is done with fatal WWD incidents on freeway systems. It suffices to say that while engineering countermeasures should evolve from the traditional signing and pavement markings to connected vehicle technology applications, there is a clear and compelling need to focus on educational campaigns specifically targeting drunken driving, and enforcement initiatives with an objective to mitigate WWD in the most efficient manner possible. Keywords: Wrong-way driving, Modeling, Arterials and freeways, Logistic regression, Likelihood

Comparison of moped, scooter and motorcycle crash risk and crash severity.

Science.gov (United States)

Blackman, Ross A; Haworth, Narelle L

2013-08-01

The increased popularity of mopeds and motor scooters in Australia and elsewhere in the last decade has contributed substantially to the greater use of powered two-wheelers (PTWs) as a whole. As the exposure of mopeds and scooters has increased, so too has the number of reported crashes involving those PTW types, but there is currently little research comparing the safety of mopeds and, particularly, larger scooters with motorcycles. This study compared the crash risk and crash severity of motorcycles, mopeds and larger scooters in Queensland, Australia. Comprehensive data cleansing was undertaken to separate motorcycles, mopeds and larger scooters in police-reported crash data covering the five years to 30 June 2008. The crash rates of motorcycles (including larger scooters) and mopeds in terms of registered vehicles were similar over this period, although the moped crash rate showed a stronger downward trend. However, the crash rates in terms of distance travelled were nearly four times higher for mopeds than for motorcycles (including larger scooters). More comprehensive distance travelled data is needed to confirm these findings. The overall severity of moped and scooter crashes was significantly lower than motorcycle crashes but an ordered probit regression model showed that crash severity outcomes related to differences in crash characteristics and circumstances, rather than differences between PTW types per se. Greater motorcycle crash severity was associated with higher (>80km/h) speed zones, horizontal curves, weekend, single vehicle and nighttime crashes. Moped crashes were more severe at night and in speed zones of 90km/h or more. Larger scooter crashes were more severe in 70km/h zones (than 60km/h zones) but not in higher speed zones, and less severe on weekends than on weekdays. The findings can be used to inform potential crash and injury countermeasures tailored to users of different PTW types. Copyright © 2013 Elsevier Ltd. All rights reserved.

Use of car crashes resulting in fatal and serious injuries to analyze a safe road transport system model and to identify system weaknesses.

Science.gov (United States)

Stigson, Helena; Hill, Julian

2009-10-01

The objective of this study was to evaluate a model for a safe road transport system, based on some safety performance indicators regarding the road user, the vehicle, and the road, by using crashes with fatally and seriously injured car occupants. The study also aimed to evaluate whether the model could be used to identify system weaknesses and components (road user, vehicles, and road) where improvements would yield the highest potential for further reductions in serious injuries. Real-life car crashes with serious injury outcomes (Maximum Abbreviated Injury Scale 2+) were classified according to the vehicle's safety rating by Euro NCAP (European New Car Assessment Programme) and whether the vehicle was fitted with ESC (Electronic Stability Control). For each crash, the road was also classified according to EuroRAP (European Road Assessment Programme) criteria, and human behavior in terms of speeding, seat belt use, and driving under the influence of alcohol/drugs. Each crash was compared and classified according to the model criteria. Crashes where the safety criteria were not met in more than one of the 3 components were reclassified to identify whether all the components were correlated to the injury outcome. In-depth crash injury data collected by the UK On The Spot (OTS) accident investigation project was used in this study. All crashes in the OTS database occurring between 2000 and 2005 with a car occupant with injury rated MAIS2+ were included, for a total of 101 crashes with 120 occupants. It was possible to classify 90 percent of the crashes according to the model. Eighty-six percent of the occupants were injured when more than one of the 3 components were noncompliant with the safety criteria. These cases were reclassified to identify whether all of the components were correlated to the injury outcome. In 39 of the total 108 cases, at least two components were still seen to interact. The remaining cases were only related to one of the safety criteria

2004 road traffic crashes in Queensland

Science.gov (United States)

2009-05-01

This report presents an overview of reported road traffic crashes in Queensland during : 2004 in the context of the previous five years based on data contained in the Queensland : Road Crash Information System maintained by the Department of Transpor...

Effect of Accounting for Crash Severity on the Relationship between Mass Reduction and Crash Frequency and Risk per Crash

Energy Technology Data Exchange (ETDEWEB)

Wenzel, Tom P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Building Technology and Urban Systems Division. Energy Technologies Area

2016-05-20

Previous analyses have indicated that mass reduction is associated with an increase in crash frequency (crashes per VMT), but a decrease in fatality or casualty risk once a crash has occurred, across all types of light-duty vehicles. These results are counter-intuitive: one would expect that lighter, and perhaps smaller, vehicles have better handling and shorter braking distances, and thus should be able to avoid crashes that heavier vehicles cannot. And one would expect that heavier vehicles would have lower risk once a crash has occurred than lighter vehicles. However, these trends occur under several alternative regression model specifications. This report tests whether these results continue to hold after accounting for crash severity, by excluding crashes that result in relatively minor damage to the vehicle(s) involved in the crash. Excluding non-severe crashes from the initial LBNL Phase 2 and simultaneous two-stage regression models for the most part has little effect on the unexpected relationships observed in the baseline regression models. This finding suggests that other subtle differences in vehicles and/or their drivers, or perhaps biases in the data reported in state crash databases, are causing the unexpected results from the regression models.

Development of a continuous motorcycle protection barrier system using computer simulation and full-scale crash testing.

Science.gov (United States)

Atahan, Ali O; Hiekmann, J Marten; Himpe, Jeffrey; Marra, Joseph

2018-07-01

Road restraint systems are designed to minimize the undesirable effects of roadside accidents and improve safety of road users. These systems are utilized at either side or median section of roads to contain and redirect errant vehicles. Although restraint systems are mainly designed against car, truck and bus impacts there is an increasing pressure by the motorcycle industry to incorporate motorcycle protection systems into these systems. In this paper development details of a new and versatile motorcycle barrier, CMPS, coupled with an existing vehicle barrier is presented. CMPS is intended to safely contain and redirect motorcyclists during a collision event. First, crash performance of CMPS design is evaluated by means of a three dimensional computer simulation program LS-DYNA. Then full-scale crash tests are used to verify the acceptability of CMPS design. Crash tests were performed at CSI proving ground facility using a motorcycle dummy in accordance with prEN 1317-8 specification. Full-scale crash test results show that CMPS is able to successfully contain and redirect dummy with minimal injury risk on the dummy. Damage on the barrier is also minimal proving the robustness of the CMPS design. Based on the test findings and further review by the authorities the implementation of CMPS was recommended at highway system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cyclist–motorist crash patterns in Denmark: A latent class clustering approach

DEFF Research Database (Denmark)

Kaplan, Sigal; Prato, Carlo Giacomo

2013-01-01

to prioritize safety issues and to devise efficient preventive measures. Method: The current study focused on cyclist–motorist crashes that occurred in Denmark during the period between 2007 and 2011. To uncover crash patterns, the current analysis applied latent class clustering, an unsupervised probabilistic...

Activity modes selection for project crashing through deterministic simulation

Directory of Open Access Journals (Sweden)

Ashok Mohanty

2011-12-01

Full Text Available Purpose: The time-cost trade-off problem addressed by CPM-based analytical approaches, assume unlimited resources and the existence of a continuous time-cost function. However, given the discrete nature of most resources, the activities can often be crashed only stepwise. Activity crashing for discrete time-cost function is also known as the activity modes selection problem in the project management. This problem is known to be NP-hard. Sophisticated optimization techniques such as Dynamic Programming, Integer Programming, Genetic Algorithm, Ant Colony Optimization have been used for finding efficient solution to activity modes selection problem. The paper presents a simple method that can provide efficient solution to activity modes selection problem for project crashing.Design/methodology/approach: Simulation based method implemented on electronic spreadsheet to determine activity modes for project crashing. The method is illustrated with the help of an example.Findings: The paper shows that a simple approach based on simple heuristic and deterministic simulation can give good result comparable to sophisticated optimization techniques.Research limitations/implications: The simulation based crashing method presented in this paper is developed to return satisfactory solutions but not necessarily an optimal solution.Practical implications: The use of spreadsheets for solving the Management Science and Operations Research problems make the techniques more accessible to practitioners. Spreadsheets provide a natural interface for model building, are easy to use in terms of inputs, solutions and report generation, and allow users to perform what-if analysis.Originality/value: The paper presents the application of simulation implemented on a spreadsheet to determine efficient solution to discrete time cost tradeoff problem.

Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

Science.gov (United States)

Donier, Jonathan; Bouchaud, Jean-Philippe

2015-01-01

Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes.

Fatal crashes of passenger vehicles before and after adding antilock braking systems.

Science.gov (United States)

Farmer, C M; Lund, A K; Trempel, R E; Braver, E R

1997-11-01

Fatal crash rates of passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. Vehicles selected for analysis had no other significant design changes between the model years being compared, and the model years with and without antilocks were no more than two years apart. The overall fatal crash rates were similar for the two model years. However, the vehicles with antilocks were significantly more likely to be involved in crashes fatal to their own occupants, particularly single-vehicle crashes. Conversely, antilock vehicles were less likely to be involved in crashes fatal to occupants of other vehicles or nonoccupants (pedestrians, bicyclists). Overall, antilock brakes appear to have had little effect on fatal crash involvement. Further study is needed to better understand why fatality risk has increased for occupants of antilock vehicles.

Contributory factors to traffic crashes at signalized intersections in Hong Kong.

Science.gov (United States)

Wong, S C; Sze, N N; Li, Y C

2007-11-01

Efficient geometric design and signal timing not only improve operational performance at signalized intersections by expanding capacity and reducing traffic delays, but also result in an appreciable reduction in traffic conflicts, and thus better road safety. Information on the incidence of crashes, traffic flow, geometric design, road environment, and traffic control at 262 signalized intersections in Hong Kong during 2002 and 2003 are incorporated into a crash prediction model. Poisson regression and negative binomial regression are used to quantify the influence of possible contributory factors on the incidence of killed and severe injury (KSI) crashes and slight injury crashes, respectively, while possible interventions by traffic flow are controlled. The results for the incidence of slight injury crashes reveal that the road environment, degree of curvature, and presence of tram stops are significant factors, and that traffic volume has a diminishing effect on the crash risk. The presence of tram stops, number of pedestrian streams, road environment, proportion of commercial vehicles, average lane width, and degree of curvature increase the risk of KSI crashes, but the effect of traffic volume is negligible.

Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

Directory of Open Access Journals (Sweden)

Jonathan Donier

Full Text Available Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes.

Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights

Science.gov (United States)

Donier, Jonathan; Bouchaud, Jean-Philippe

2015-01-01

Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes. PMID:26448333

Perbandingan Stock Market Crash 1987 : Dan Stock Market Crash 1997

OpenAIRE

Indridewi Atmadjaja, Yovita Vivianty

1999-01-01

Stock market crash refers to the condition, which is marked with the large dropping of stock Market price index. Historically, stock market crash has happened three times, namely in 1929, 1987 and 1997. This paper will discuss the causes of 1987's and 1997's stock market Crash and the similarities and the differences between 1987's and 1997's stock market crash. The structure of the paper is as follows. The paper starts with the introduction. The second Section briefly explains the causes of ...

Crash probability estimation via quantifying driver hazard perception.

Science.gov (United States)

Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang

2018-07-01

Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using linked data to evaluate hospital charges for motor vehicle crash victims in Pennsylvania : Crash Outcome Data Evaluation System (CODES) linked data demonstration project

Science.gov (United States)

1998-10-01

The report uses police-reported crash data that have been linked to hospital discharge data to evaluate charges for hospital care provided to motor vehicle crash victims in Pennsylvania. Approximately 17,000 crash victims were hospitalized in Pennsyl...

Naturalistic Assessment of Novice Teenage Crash Experience

Science.gov (United States)

Lee, Suzanne E.; Simons-Morton, Bruce G.; Klauer, Sheila E.; Ouimet, Marie Claude; Dingus, Thomas A.

2011-01-01

Background Crash risk is highest during the first months after licensure. Current knowledge about teenagers’ driving exposure and the factors increasing their crash risk is based on self-reported data and crash database analyses. While these research tools are useful, new developments in naturalistic technologies have allowed researchers to examine newly-licensed teenagers’ exposure and crash risk factors in greater detail. The Naturalistic Teenage Driving Study (NTDS) described in this paper is the first study to follow a group of newly-licensed teenagers continuously for 18 months after licensure. The goals of this paper are to compare the crash and near-crash experience of drivers in the NTDS to national trends, to describe the methods and lessons learned in the NTDS, and to provide initial data on driving exposure for these drivers. Methods A data acquisition system was installed in the vehicles of 42 newly-licensed teenage drivers 16 years of age during their first 18 months of independent driving. It consisted of cameras, sensors (accelerometers, GPS, yaw, front radar, lane position, and various sensors obtained via the vehicle network), and a computer with removable hard drive. Data on the driving of participating parents was also collected when they drove the instrumented vehicle. Findings The primary findings after 18 months included the following: (1) crash and near-crash rates among teenage participants were significantly higher during the first six months of the study than the final 12 months, mirroring the national trends; (2) crash and near-crash rates were significantly higher for teenage than adult (parent) participants, also reflecting national trends; (3) teenaged driving exposure averaged between 507-710 kilometers (315-441 miles) per month over the study period, but varied substantially between participants with standard errors representing 8-14 percent of the mean; and (4) crash and near-crash types were very similar for male and female

Prevalence of driver physical factors leading to unintentional lane departure crashes.

Science.gov (United States)

Cicchino, Jessica B; Zuby, David S

2017-07-04

Some lane-keeping assist systems in development and production provide autonomous braking and steering to correct unintentional lane drift but otherwise require drivers to fully control their vehicles. The goal of this study was to quantify the proportion of drivers involved in unintentional lane drift crashes who would be unable to regain control of their vehicles to inform the design of such systems. The NHTSA's National Motor Vehicle Crash Causation Survey collected in-depth, on-scene data for a nationally representative sample of 5,470 U.S. police-reported passenger vehicle crashes during 2005-2007 that occurred between 6 a.m. and midnight and for which emergency medical services were dispatched. The physical states of drivers involved in the 631 lane drift crashes in the sample, which represented 259,034 crashes nationally, were characterized. Thirty-four percent of drivers who crashed because they drifted from their lanes were sleeping or otherwise incapacitated. These drivers would be unlikely to regain full control of their vehicles if an active safety system prevented their initial drift. An additional 13% of these drivers had a nonincapacitating medical issue, blood alcohol concentration (BAC) ≥ 0.08%, or other physical factor that may not allow them to regain full vehicle control. When crashes involved serious or fatal injuries, 42% of drivers who drifted were sleeping or otherwise incapacitated, and an additional 14% were impacted by a nonincapacitating medical issue, BAC ≥ 0.08%, or other physical factor. Designers of active safety systems that provide autonomous lateral control should consider that a substantial proportion of drivers at risk of lane drift crashes are incapacitated. Systems that provide only transient corrective action may not ultimately prevent lane departure crashes for these drivers, and drivers who do avoid lane drift crashes because of these systems may be at high risk of other types of crashes when they attempt to regain

Direct medical costs of motorcycle crashes in Ontario.

Science.gov (United States)

Pincus, Daniel; Wasserstein, David; Nathens, Avery B; Bai, Yu Qing; Redelmeier, Donald A; Wodchis, Walter P

2017-11-20

There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively ( p motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety. © 2017 Joule Inc. or its licensors.

Critical market crashes

Science.gov (United States)

Sornette, D.

2003-04-01

This review presents a general theory of financial crashes and of stock market instabilities that his co-workers and the author have developed over the past seven years. We start by discussing the limitation of standard analyses for characterizing how crashes are special. The study of the frequency distribution of drawdowns, or runs of successive losses shows that large financial crashes are “outliers”: they form a class of their own as can be seen from their statistical signatures. If large financial crashes are “outliers”, they are special and thus require a special explanation, a specific model, a theory of their own. In addition, their special properties may perhaps be used for their prediction. The main mechanisms leading to positive feedbacks, i.e., self-reinforcement, such as imitative behavior and herding between investors are reviewed with many references provided to the relevant literature outside the narrow confine of Physics. Positive feedbacks provide the fuel for the development of speculative bubbles, preparing the instability for a major crash. We demonstrate several detailed mathematical models of speculative bubbles and crashes. A first model posits that the crash hazard drives the market price. The crash hazard may sky-rocket at some times due to the collective behavior of “noise traders”, those who act on little information, even if they think they “know”. A second version inverses the logic and posits that prices drive the crash hazard. Prices may skyrocket at some times again due to the speculative or imitative behavior of investors. According the rational expectation model, this entails automatically a corresponding increase of the probability for a crash. We also review two other models including the competition between imitation and contrarian behavior and between value investors and technical analysts. The most important message is the discovery of robust and universal signatures of the approach to crashes. These precursory

Motorcycle crash causes and outcomes : pilot study.

Science.gov (United States)

2010-06-01

The number of motorcyclist crash-related fatalities has more than doubled during the past 10 years. In the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) P.L. 109-59, Congress directed the Secretary ...

Correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists in single-vehicle crashes.

Science.gov (United States)

Wang, Chen; Lu, Linjun; Lu, Jian; Wang, Tao

2016-01-01

In order to improve motorcycle safety, this article examines the correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists, under multiple precrash conditions. Ten-year crash data for single-vehicle motorcycle crashes from the General Estimates Systems (GES) were analyzed, using partial proportional odds models (i.e., generalized ordered logit models). The modeling results show that "braking (no lock-up)" is associated with a higher probability of increased severity, whereas "braking (lock-up)" is associated with a higher probability of decreased severity, under all precrash conditions. "Steering" is associated with a higher probability of reduced injury severity when other vehicles are encroaching, whereas it is correlated with high injury severity under other conditions. "Braking and steering" is significantly associated with a higher probability of low severity under "animal encounter and object presence," whereas it is surprisingly correlated with high injury severity when motorcycles are traveling off the edge of the road. The results also show that a large number of motorcyclists did not perform any crash avoidance maneuvers or conducted crash avoidance maneuvers that are significantly associated with high injury severity. In general, this study suggests that precrash maneuvers are an important factor associated with motorcyclists' injury severity. To improve motorcycle safety, training/educational programs should be considered to improve safety awareness and adjust driving habits of motorcyclists. Antilock brakes and such systems are also promising, because they could effectively prevent brake lock-up and assist motorcyclists in maneuvering during critical conditions. This study also provides valuable information for the design of motorcycle training curriculum.

Vehicular crash data used to rank intersections by injury crash frequency and severity

Directory of Open Access Journals (Sweden)

Yi Liu

2016-09-01

Full Text Available This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016 [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO, and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.

Statistical modeling of total crash frequency at highway intersections

Directory of Open Access Journals (Sweden)

Arash M. Roshandeh

2016-04-01

Full Text Available Intersection-related crashes are associated with high proportion of accidents involving drivers, occupants, pedestrians, and cyclists. In general, the purpose of intersection safety analysis is to determine the impact of safety-related variables on pedestrians, cyclists and vehicles, so as to facilitate the design of effective and efficient countermeasure strategies to improve safety at intersections. This study investigates the effects of traffic, environmental, intersection geometric and pavement-related characteristics on total crash frequencies at intersections. A random-parameter Poisson model was used with crash data from 357 signalized intersections in Chicago from 2004 to 2010. The results indicate that out of the identified factors, evening peak period traffic volume, pavement condition, and unlighted intersections have the greatest effects on crash frequencies. Overall, the results seek to suggest that, in order to improve effective highway-related safety countermeasures at intersections, significant attention must be focused on ensuring that pavements are adequately maintained and intersections should be well lighted. It needs to be mentioned that, projects could be implemented at and around the study intersections during the study period (7 years, which could affect the crash frequency over the time. This is an important variable which could be a part of the future studies to investigate the impacts of safety-related works at intersections and their marginal effects on crash frequency at signalized intersections.

Crash data and rates for age-sex groups of drivers, 1996

Science.gov (United States)

1998-01-01

The results of this research note are based on 1996data for fatal crashes, driver licenses, and estimates of total crashes based upon data obtained from the nationally representative sample of crashes gathered in the General Estimates System (GES). T...

Camera systems for crash and hyge testing

Science.gov (United States)

Schreppers, Frederik

1995-05-01

Since the beginning of the use of high speed cameras for crash and hyge- testing substantial changements have taken place. Both the high speed cameras and the electronic control equipment are more sophisticated nowadays. With regard to high speed equipment, a short historical retrospective view will show that concerning high speed cameras, the improvements are mainly concentrated in design details, where as the electronic control equipment has taken full advantage of the rapid progress in electronic and computer technology in the course of the last decades. Nowadays many companies and institutes involved in crash and hyge-testing wish to perform this testing, as far as possible, as an automatic computer controlled routine in order to maintain and improve security and quality. By means of several in practice realize solutions, it will be shown how their requirements could be met.

Evaluation of Vehicle-Based Crash Severity Metrics.

Science.gov (United States)

Tsoi, Ada H; Gabler, Hampton C

2015-01-01

Vehicle change in velocity (delta-v) is a widely used crash severity metric used to estimate occupant injury risk. Despite its widespread use, delta-v has several limitations. Of most concern, delta-v is a vehicle-based metric which does not consider the crash pulse or the performance of occupant restraints, e.g. seatbelts and airbags. Such criticisms have prompted the search for alternative impact severity metrics based upon vehicle kinematics. The purpose of this study was to assess the ability of the occupant impact velocity (OIV), acceleration severity index (ASI), vehicle pulse index (VPI), and maximum delta-v (delta-v) to predict serious injury in real world crashes. The study was based on the analysis of event data recorders (EDRs) downloaded from the National Automotive Sampling System / Crashworthiness Data System (NASS-CDS) 2000-2013 cases. All vehicles in the sample were GM passenger cars and light trucks involved in a frontal collision. Rollover crashes were excluded. Vehicles were restricted to single-event crashes that caused an airbag deployment. All EDR data were checked for a successful, completed recording of the event and that the crash pulse was complete. The maximum abbreviated injury scale (MAIS) was used to describe occupant injury outcome. Drivers were categorized into either non-seriously injured group (MAIS2-) or seriously injured group (MAIS3+), based on the severity of any injuries to the thorax, abdomen, and spine. ASI and OIV were calculated according to the Manual for Assessing Safety Hardware. VPI was calculated according to ISO/TR 12353-3, with vehicle-specific parameters determined from U.S. New Car Assessment Program crash tests. Using binary logistic regression, the cumulative probability of injury risk was determined for each metric and assessed for statistical significance, goodness-of-fit, and prediction accuracy. The dataset included 102,744 vehicles. A Wald chi-square test showed each vehicle-based crash severity metric

Solutions for acceleration measurement in vehicle crash tests

Science.gov (United States)

Dima, D. S.; Covaciu, D.

2017-10-01

Crash tests are useful for validating computer simulations of road traffic accidents. One of the most important parameters measured is the acceleration. The evolution of acceleration versus time, during a crash test, form a crash pulse. The correctness of the crash pulse determination depends on the data acquisition system used. Recommendations regarding the instrumentation for impact tests are given in standards, which are focused on the use of accelerometers as impact sensors. The goal of this paper is to present the device and software developed by authors for data acquisition and processing. The system includes two accelerometers with different input ranges, a processing unit based on a 32-bit microcontroller and a data logging unit with SD card. Data collected on card, as text files, is processed with a dedicated software running on personal computers. The processing is based on diagrams and includes the digital filters recommended in standards.

New evidence concerning fatal crashes of passenger vehicles before and after adding antilock braking systems.

Science.gov (United States)

Farmer, C M

2001-05-01

Fatal crash rates for passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. A prior study, based on fatal crash experience through 1995, reported that vehicle models with antilock brakes were more likely than identical but 1-year-earlier models to be involved in crashes fatal to their own occupants, but were less likely to be involved in crashes fatal to occupants of other vehicles. Overall, there was no significant effect of antilocks on the likelihood of fatal crashes. Similar analyses, based on fatal crash experience during 1996-98, yielded very different results. During 1996-98, vehicles with antilock brakes were again less likely than earlier models to be involved in crashes fatal to occupants of other vehicles, but they were no longer overinvolved in crashes fatal to their own occupants.

Fatal motorcycle crashes: a growing public health problem in Cambodia.

Science.gov (United States)

Roehler, Douglas R; Ear, Chariya; Parker, Erin M; Sem, Panhavuth; Ballesteros, Michael F

2015-01-01

This study examines the risk characteristics of fatal motorcycle crashes in Cambodia over a 5-year period (2007-2011). Secondary data analyses were conducted using the Cambodia Road Crash and Victim Information System, the only comprehensive and integrated road crash surveillance system in the country. Researchers from the Centers for Disease Control and Prevention and Handicap International found that (1) males are dying in motorcycle crashes roughly seven times more frequently than females; (2) motorcyclist fatalities increased by about 30% from 2007 to 2011; (3) the motorcyclist death rates per 100,000 population increased from 7.4 to 8.7 deaths from 2007 to 2011; and (4) speed-related crashes and not wearing motorcycle helmet were commonly reported for motorcyclist fatalities at approximately 50% and over 80% through the study years, respectively. Additionally, this study highlights that Cambodia has the highest motorcycle death rate in South-East Asia, far surpassing Thailand, Malaysia, and Myanmar. By recognising the patterns of fatal motorcycle crashes in Cambodia, local road-safety champions and stakeholders can design targeted interventions and preventative measures to improve road safety among motorcyclists.

Predicting motorcycle crash injury severity using weather data and alternative Bayesian multivariate crash frequency models.

Science.gov (United States)

Cheng, Wen; Gill, Gurdiljot Singh; Sakrani, Taha; Dasu, Mohan; Zhou, Jiao

2017-11-01

Motorcycle crashes constitute a very high proportion of the overall motor vehicle fatalities in the United States, and many studies have examined the influential factors under various conditions. However, research on the impact of weather conditions on the motorcycle crash severity is not well documented. In this study, we examined the impact of weather conditions on motorcycle crash injuries at four different severity levels using San Francisco motorcycle crash injury data. Five models were developed using Full Bayesian formulation accounting for different correlations commonly seen in crash data and then compared for fitness and performance. Results indicate that the models with serial and severity variations of parameters had superior fit, and the capability of accurate crash prediction. The inferences from the parameter estimates from the five models were: an increase in the air temperature reduced the possibility of a fatal crash but had a reverse impact on crashes of other severity levels; humidity in air was not observed to have a predictable or strong impact on crashes; the occurrence of rainfall decreased the possibility of crashes for all severity levels. Transportation agencies might benefit from the research results to improve road safety by providing motorcyclists with information regarding the risk of certain crash severity levels for special weather conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of teen and adult driver crash scenarios in a nationally representative sample of serious crashes.

Science.gov (United States)

McDonald, Catherine C; Curry, Allison E; Kandadai, Venk; Sommers, Marilyn S; Winston, Flaura K

2014-11-01

Motor vehicle crashes are the leading cause of death and acquired disability during the first four decades of life. While teen drivers have the highest crash risk, few studies examine the similarities and differences in teen and adult driver crashes. We aimed to: (1) identify and compare the most frequent crash scenarios-integrated information on a vehicle's movement prior to crash, immediate pre-crash event, and crash configuration-for teen and adult drivers involved in serious crashes, and (2) for the most frequent scenarios, explore whether the distribution of driver critical errors differed for teens and adult drivers. We analyzed data from the National Motor Vehicle Crash Causation Survey, a nationally representative study of serious crashes conducted by the U.S. National Highway Traffic Safety Administration from 2005 to 2007. Our sample included 642 16- to 19-year-old and 1167 35- to 54-year-old crash-involved drivers (weighted n=296,482 and 439,356, respectively) who made a critical error that led to their crash's critical pre-crash event (i.e., event that made the crash inevitable). We estimated prevalence ratios (PR) and 95% confidence intervals (CI) to compare the relative frequency of crash scenarios and driver critical errors. The top five crash scenarios among teen drivers, accounting for 37.3% of their crashes, included: (1) going straight, other vehicle stopped, rear end; (2) stopped in traffic lane, turning left at intersection, turn into path of other vehicle; (3) negotiating curve, off right edge of road, right roadside departure; (4) going straight, off right edge of road, right roadside departure; and (5) stopped in lane, turning left at intersection, turn across path of other vehicle. The top five crash scenarios among adult drivers, accounting for 33.9% of their crashes, included the same scenarios as the teen drivers with the exception of scenario (3) and the addition of going straight, crossing over an intersection, and continuing on a

Hotspots and causes of motor vehicle crashes in Baltimore, Maryland: A geospatial analysis of five years of police crash and census data.

Science.gov (United States)

Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A

2016-11-01

Road traffic injuries are a leading killer of youth (aged 15-29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of

Evaluation of safety ratings of roads based on frontal crashes with known crash pulse and injury outcome.

Science.gov (United States)

Stigson, H

2009-06-01

The objective in this study, using data from crashed cars fitted with on-board crash pulse recorders, was to present differences in average crash severity, distribution of crash severity, and injury outcomes, based on an independent safety rating of roads, also taking road type and speed limit into consideration. Furthermore, the objective was to evaluate differences in injury risk, based on the distribution of crash severity. The investigation included both frontal two-vehicle crashes and single-vehicle crashes with known injury outcome. In total, 209 real-world crashes involving cars fitted with crash pulse recorders were included. For all crashes, average mean acceleration and change of velocity of the vehicle acceleration pulse were measured and calculated. All crash spots were classified according to an independent road safety rating program (European Road Assessment Programme Road Protection Score), where the safety quality of roads is rated in relation to posted speed limits. The crash severity and injury outcome in crashes that occurred on roads with good safety ratings were compared with crashes on roads with poor safety ratings. The data were also divided into subcategories according to posted speed limit and road type, to evaluate whether there was a difference in crash severity and injury outcome within the categories. In total, crash severity was statistically significantly lower in crashes occurring on roads with good safety ratings than in crashes occurring on roads with poor safety ratings. It was found that crash severity and injury risk were lower on roads with good safety ratings with a speed limit of above 90 km/h compared with roads with poor safety ratings, irrespective of speed limit. On the other hand, crash severity was higher on roads with good safety ratings with speed limit of 70 km/h than on roads with poor safety ratings with the same speed limit. Though it was found that a higher speed limit resulted in higher crash severity on roads

Crash risk factors for interstate large trucks in North Carolina.

Science.gov (United States)

Teoh, Eric R; Carter, Daniel L; Smith, Sarah; McCartt, Anne T

2017-09-01

Provide an updated examination of risk factors for large truck involvements in crashes resulting in injury or death. A matched case-control study was conducted in North Carolina of large trucks operated by interstate carriers. Cases were defined as trucks involved in crashes resulting in fatal or non-fatal injury, and one control truck was matched on the basis of location, weekday, time of day, and truck type. The matched-pair odds ratio provided an estimate of the effect of various driver, vehicle, or carrier factors. Out-of-service (OOS) brake violations tripled the risk of crashing; any OOS vehicle defect increased crash risk by 362%. Higher historical crash rates (fatal, injury, or all crashes) of the carrier were associated with increased risk of crashing. Operating on a short-haul exemption increased crash risk by 383%. Antilock braking systems reduced crash risk by 65%. All of these results were statistically significant at the 95% confidence level. Other safety technologies also showed estimated benefits, although not statistically significant. With the exception of the finding that short-haul exemption is associated with increased crash risk, results largely bolster what is currently known about large truck crash risk and reinforce current enforcement practices. Results also suggest vehicle safety technologies can be important in lowering crash risk. This means that as safety technology continues to penetrate the fleet, whether from voluntary usage or government mandates, reductions in large truck crashes may be achieved. Practical application: Results imply that increased enforcement and use of crash avoidance technologies can improve the large truck crash problem. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Evaluating impacts of different longitudinal driver assistance systems on reducing multi-vehicle rear-end crashes during small-scale inclement weather.

Science.gov (United States)

Li, Ye; Xing, Lu; Wang, Wei; Wang, Hao; Dong, Changyin; Liu, Shanwen

2017-10-01

Multi-vehicle rear-end (MVRE) crashes during small-scale inclement (SSI) weather cause high fatality rates on freeways, which cannot be solved by traditional speed limit strategies. This study aimed to reduce MVRE crash risks during SSI weather using different longitudinal driver assistance systems (LDAS). The impact factors on MVRE crashes during SSI weather were firstly analyzed. Then, four LDAS, including Forward collision warning (FCW), Autonomous emergency braking (AEB), Adaptive cruise control (ACC) and Cooperative ACC (CACC), were modeled based on a unified platform, the Intelligent Driver Model (IDM). Simulation experiments were designed and a large number of simulations were then conducted to evaluate safety effects of different LDAS. Results indicate that the FCW and ACC system have poor performance on reducing MVRE crashes during SSI weather. The slight improvement of sight distance of FCW and the limitation of perception-reaction time of ACC lead the failure of avoiding MVRE crashes in most scenarios. The AEB system has the better effect due to automatic perception and reaction, as well as performing the full brake when encountering SSI weather. The CACC system has the best performance because wireless communication provides a larger sight distance and a shorter time delay at the sub-second level. Sensitivity analyses also indicated that the larger number of vehicles and speed changes after encountering SSI weather have negative impacts on safety performances. Results of this study provide useful information for accident prevention during SSI weather. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fatal crashes involving large numbers of vehicles and weather.

Science.gov (United States)

Wang, Ying; Liang, Liming; Evans, Leonard

2017-12-01

Adverse weather has been recognized as a significant threat to traffic safety. However, relationships between fatal crashes involving large numbers of vehicles and weather are rarely studied according to the low occurrence of crashes involving large numbers of vehicles. By using all 1,513,792 fatal crashes in the Fatality Analysis Reporting System (FARS) data, 1975-2014, we successfully described these relationships. We found: (a) fatal crashes involving more than 35 vehicles are most likely to occur in snow or fog; (b) fatal crashes in rain are three times as likely to involve 10 or more vehicles as fatal crashes in good weather; (c) fatal crashes in snow [or fog] are 24 times [35 times] as likely to involve 10 or more vehicles as fatal crashes in good weather. If the example had used 20 vehicles, the risk ratios would be 6 for rain, 158 for snow, and 171 for fog. To reduce the risk of involvement in fatal crashes with large numbers of vehicles, drivers should slow down more than they currently do under adverse weather conditions. Driver deaths per fatal crash increase slowly with increasing numbers of involved vehicles when it is snowing or raining, but more steeply when clear or foggy. We conclude that in order to reduce risk of involvement in crashes involving large numbers of vehicles, drivers must reduce speed in fog, and in snow or rain, reduce speed by even more than they already do. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Vehicular crash data used to rank intersections by injury crash frequency and severity

OpenAIRE

Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar

2016-01-01

This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, modera...

Origin of crashes in three US stock markets: shocks and bubbles

Science.gov (United States)

Johansen, Anders

2004-07-01

This paper presents an exclusive classification of the largest crashes in Dow Jones industrial average, SP500 and NASDAQ in the past century. Crashes are objectively defined as the top-rank filtered drawdowns (loss from the last local maximum to the next local minimum disregarding noise fluctuations), where the size of the filter is determined by the historical volatility of the index. It is shown that all crashes can be linked to either an external shock, e.g., outbreak of war, or a log-periodic power law (LPPL) bubble with an empirically well-defined complex value of the exponent. Conversely, with one sole exception all previously identified LPPL bubbles are followed by a top-rank drawdown. As a consequence, the analysis presented suggest a one-to-one correspondence between market crashes defined as top-rank filtered drawdowns on one hand and surprising news and LPPL bubbles on the other. We attribute this correspondence to the efficient market hypothesis effective on two quite different time scales depending on whether the market instability the crash represent is internally or externally generated.

Cirrus Airframe Parachute System and Odds of a Fatal Accident in Cirrus Aircraft Crashes.

Science.gov (United States)

Alaziz, Mustafa; Stolfi, Adrienne; Olson, Dean M

2017-06-01

General aviation (GA) accidents have continued to demonstrate high fatality rates. Recently, ballistic parachute recovery systems (BPRS) have been introduced as a safety feature in some GA aircraft. This study evaluates the effectiveness and associated factors of the Cirrus Airframe Parachute System (CAPS) at reducing the odds of a fatal accident in Cirrus aircraft crashes. Publicly available Cirrus aircraft crash reports were obtained from the National Transportation Safety Board (NTSB) database for the period of January 1, 2001-December 31, 2016. Accident metrics were evaluated through univariate and multivariate analyses regarding odds of a fatal accident and use of the parachute system. Included in the study were 268 accidents. For CAPS nondeployed accidents, 82 of 211 (38.9%) were fatal as compared to 8 of 57 (14.0%) for CAPS deployed accidents. After controlling for all other factors, the adjusted odds ratio for a fatal accident when CAPS was not deployed was 13.1. The substantial increased odds of a fatal accident when CAPS was not deployed demonstrated the effectiveness of CAPS at providing protection of occupants during an accident. Injuries were shifted from fatal to serious or minor with the use of CAPS and postcrash fires were significantly reduced. These results suggest that BPRS could play a significant role in the next major advance in improving GA accident survival.Alaziz M, Stolfi A, Olson DM. Cirrus Airframe Parachute System and odds of a fatal accident in Cirrus aircraft crashes. Aerosp Med Hum Perform. 2017; 88(6):556-564.

An anticipative escape system for vehicles in water crashes

Science.gov (United States)

Shen, Chuanliang; Wang, Jiawei; Yin, Qi; Zhu, Yantao; Yang, Jiawei; Liao, Mengdi; Yang, Liming

2017-07-01

In this article, it designs an escape system for vehicles in water crashes. The structure mainly contains sensors, control organs and actuating mechanism for both doors and windows. Sensors judge whether the vehicle falls into water or is in the falling process. The actuating mechanism accepts the signal delivered by the control organs, then open the electronic central lock on doors and meanwhile lower the window. The water escape system is able to anticipate drowning situations for vehicles and controls both doors and windows in such an emergency. Under the premise of doors staying in an undamaged state, it is for sure that people in the vehicle can open the door while drowning in the water and safely escape.

Time-varying Crash Risk

DEFF Research Database (Denmark)

Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae

We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly on re...

A collaborative processes synchronization method with regard to system crashes and network failures

NARCIS (Netherlands)

Wang, Lei; Wombacher, Andreas; Ferreira Pires, Luis; van Sinderen, Marten J.; Chi, Chihung

2014-01-01

Processes can synchronize their states by exchanging messages. System crashes and network failures may cause message loss, so that state changes of a process may remain unnoticed by its partner processes, resulting in state inconsistency or deadlocks. In this paper we define a method to transform a

Relationship between organisational safety culture dimensions and crashes.

Science.gov (United States)

Varmazyar, Sakineh; Mortazavi, Seyed Bagher; Arghami, Shirazeh; Hajizadeh, Ebrahim

2016-01-01

Knowing about organisational safety culture in public transportation system can provide an appropriate guide to establish effective safety measures and interventions to improve safety at work. The aim of this study was investigation of association between safety culture dimensions (leadership styles and company values, usage of crashes information and prevention programmes, management commitment and safety policy, participation and control) with involved self-reported crashes. The associations were considered through Spearman correlation, Pearson chi-square test and logistic regression. The results showed an association among self-reported crashes (occurrence or non-occurrence) and factors including leadership styles and company values; management commitment and safety policy; and control. Moreover, it was found a negative correlation and an odds ratio less than one between control and self-reported crashes.

Advances in Crash Response

Centers for Disease Control (CDC) Podcasts

In this podcast, Dr. Richard C. Hunt, Director of CDC's Division of Injury Response, provides an overview on the benefits of using an Advanced Automatic Collision Notification system, or AACN, to help with emergency triage of people injured in vehicle crashes.

Relationship of Near-Crash/Crash Risk to Time Spent on a Cell Phone While Driving.

Science.gov (United States)

Farmer, Charles M; Klauer, Sheila G; McClafferty, Julie A; Guo, Feng

2015-01-01

The objective of this study was to examine in a naturalistic driving setting the dose-response relationship between cell phone usage while driving and risk of a crash or near crash. How is the increasing use of cell phones by drivers associated with overall near-crash/crash risk (i.e., during driving times both on and off the phone)? Day-to-day driving behavior of 105 volunteer subjects was monitored over a period of 1 year. A random sample was selected comprised of 4 trips from each month that each driver was in the study, and in-vehicle video was used to classify driver behavior. The proportion of driving time spent using a cell phone was estimated for each 3-month period and correlated with overall crash and near-crash rates for each period. Thus, it was possible to test whether changes in an individual driver's cell phone use over time were associated with changes in overall near-crash/crash risk. Drivers in the study spent 11.7% of their driving time interacting with a cell phone, primarily talking on the phone (6.5%) or simply holding the phone in their hand or lap (3.7%). The risk of a near-crash/crash event was approximately 17% higher when the driver was interacting with a cell phone, due primarily to actions of reaching for/answering/dialing, which nearly triples risk (relative risk = 2.84). However, the amount of driving time spent interacting with a cell phone did not affect a driver's overall near-crash/crash risk. Vehicle speeds within 6 s of the beginning of each call on average were 5-6 mph lower than speeds at other times. Results of this naturalistic driving study are consistent with the observation that increasing cell phone use in the general driving population has not led to increased crash rates. Although cell phone use can be distracting and crashes have occurred during this distraction, overall crash rates appear unaffected by changes in the rate of cell phone use, even for individual drivers. Drivers compensate somewhat for the distraction

Motorcycle crash causes and outcomes: pilot study : traffic tech.

Science.gov (United States)

2010-08-01

The number of motorcyclist crash-related fatalities has more than doubled during the past 10 years. In the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU), Congress directed the Secretary of Transport...

Safety impacts of platform tram stops on pedestrians in mixed traffic operation: A comparison group before-after crash study.

Science.gov (United States)

Naznin, Farhana; Currie, Graham; Logan, David; Sarvi, Majid

2016-01-01

Tram stops in mixed traffic environments present a variety of safety, accessibility and transport efficiency challenges. In Melbourne, Australia the hundred year-old electric tram system is progressively being modernized to improve passenger accessibility. Platform stops, incorporating raised platforms for level entry into low floor trams, are being retro-fitted system-wide to replace older design stops. The aim of this study was to investigate the safety impacts of platform stops over older design stops (i.e. Melbourne safety zone tram stops) on pedestrians in the context of mixed traffic tram operation in Melbourne, using an advanced before-after crash analysis approach, the comparison group (CG) method. The CG method evaluates safety impacts by taking into account the general trends in safety and the unobserved factors at treatment and comparison sites that can alter the outcomes of a simple before-after analysis. The results showed that pedestrian-involved all injury crashes reduced by 43% after platform stop installation. This paper also explores a concern that the conventional CG method might underestimate safety impacts as a result of large differences in passenger stop use between treatment and comparison sites, suggesting differences in crash risk exposure. To adjust for this, a modified analysis explored crash rates (crash counts per 10,000 stop passengers) for each site. The adjusted results suggested greater reductions in pedestrian-involved crashes after platform stop installation: an 81% reduction in pedestrian-involved all injury crashes and 86% reduction in pedestrian-involved FSI crashes, both are significant at the 95% level. Overall, the results suggest that platform stops have considerable safety benefits for pedestrians. Implications for policy and areas for future research are explored. Copyright © 2015 Elsevier Ltd. All rights reserved.

AP statistics crash course

CERN Document Server

D'Alessio, Michael

2012-01-01

AP Statistics Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Statistics Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Statistics course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valuable study time. Our easy-to-read format covers: exploring da

Child passengers injured in motor vehicle crashes.

Science.gov (United States)

Romano, Eduardo; Kelley-Baker, Tara

2015-02-01

During 2010, 171,000 children aged 0-14 were injured in motor vehicle crashes. Despite the severity of the problem, research has been limited, and most of what we know about these children emanates from fatal crash databases. Using information from the General Estimates System, this effort examines the occurrence of non-fatal crashes among children aged 0-14 over the last decade. We found that about 1% of the non-injured children in the file had been driven by a driver who was positive for alcohol. This percentage climbed to about 2% among children who had suffered injuries. Compared with the proportion of alcohol-positive drivers at the time of the crash, the proportion of drivers who sped or failed to obey a traffic signal was significantly higher. The finding that drinking and driving with children did not decrease over time questions the adequacy of the extant child endangerment laws. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

An investigation of the speeding-related crash designation through crash narrative reviews sampled via logistic regression.

Science.gov (United States)

Fitzpatrick, Cole D; Rakasi, Saritha; Knodler, Michael A

2017-01-01

Speed is one of the most important factors in traffic safety as higher speeds are linked to increased crash risk and higher injury severities. Nearly a third of fatal crashes in the United States are designated as "speeding-related", which is defined as either "the driver behavior of exceeding the posted speed limit or driving too fast for conditions." While many studies have utilized the speeding-related designation in safety analyses, no studies have examined the underlying accuracy of this designation. Herein, we investigate the speeding-related crash designation through the development of a series of logistic regression models that were derived from the established speeding-related crash typologies and validated using a blind review, by multiple researchers, of 604 crash narratives. The developed logistic regression model accurately identified crashes which were not originally designated as speeding-related but had crash narratives that suggested speeding as a causative factor. Only 53.4% of crashes designated as speeding-related contained narratives which described speeding as a causative factor. Further investigation of these crashes revealed that the driver contributing code (DCC) of "driving too fast for conditions" was being used in three separate situations. Additionally, this DCC was also incorrectly used when "exceeding the posted speed limit" would likely have been a more appropriate designation. Finally, it was determined that the responding officer only utilized one DCC in 82% of crashes not designated as speeding-related but contained a narrative indicating speed as a contributing causal factor. The use of logistic regression models based upon speeding-related crash typologies offers a promising method by which all possible speeding-related crashes could be identified. Published by Elsevier Ltd.

Distracted Driving Raises Crash Risk

Science.gov (United States)

... this issue Health Capsule Distracted Driving Raises Crash Risk En español Send us your comments Video technology ... distracted driving, especially among new drivers, raises the risk for car crashes and near crashes. The study ...

Use of fatal real-life crashes to analyze a safe road transport system model, including the road user, the vehicle, and the road.

Science.gov (United States)

Stigson, Helena; Krafft, Maria; Tingvall, Claes

2008-10-01

To evaluate if the Swedish Road Administration (SRA) model for a safe road transport system, which includes the interaction between the road user, the vehicle, and the road, could be used to classify fatal car crashes according to some safety indicators. Also, to present a development of the model to better identify system weakness. Real-life crashes with a fatal outcome were classified according to the vehicle's safety rating by Euro NCAP (European Road Assessment Programme) and fitment of ESC (Electronic Stability Control). For each crash, the road was also classified according to EuroRAP (European Road Assessment Programme) criteria, and human behavior in terms of speeding, seat belt use, and driving under the influence of alcohol. Each crash was compared with the model criteria, to identify components that might have contributed to fatal outcome. All fatal crashes where a car occupant was killed that occurred in Sweden during 2004 were included: in all, 215 crashes with 248 fatalities. The data were collected from the in-depth fatal crash data of the Swedish Road Administration (SRA). It was possible to classify 93% of the fatal car crashes according to the SRA model. A number of shortcomings in the criteria were identified since the model did not address rear-end or animal collisions or collisions with stationary/parked vehicles or trailers (18 out of 248 cases). Using the further developed model, it was possible to identify that most of the crashes occurred when two or all three components interacted (in 85 of the total 230 cases). Noncompliance with safety criteria for the road user, the vehicle, and the road led to fatal outcome in 43, 27, and 75 cases, respectively. The SRA model was found to be useful for classifying fatal crashes but needs to be further developed to identify how the components interact and thereby identify weaknesses in the road traffic system. This developed model might be a tool to systematically identify which of the components are

Cell phone use and traffic crash risk: a culpability analysis.

Science.gov (United States)

Asbridge, Mark; Brubacher, Jeff R; Chan, Herbert

2013-02-01

The use of a cell phone or communication device while driving is illegal in many jurisdictions, yet evidence evaluating the crash risk associated with cell phone use in naturalistic settings is limited. This article aims to determine whether cell phone use while driving increases motor vehicle crash culpability. Method Drivers involved in crashes where police reported cell phone use (n = 312) and propensity matched drivers (age, sex, suspect alcohol/drug impairment, crash type, date, time of day, geographical location) without cell phone use (n = 936) were drawn from Insurance Corporation of British Columbia Traffic Accident System data. A standardized scoring tool, modified to account for Canadian driving conditions, was used to determine crash culpability from police reports on all drivers from the crashes. The association between crash culpability and cell phone use was determined, with additional subgroup analyses based on crash severity, driver characteristics and type of licence. A comparison of crashes with vs without cell phones revealed an odds ratio of 1.70 (95% confidence interval 1.22-2.36; P = 0.002). This association was consistent after adjustment for matching variables and other covariates. Subgroup analyses demonstrated an association for male drivers, unimpaired drivers, injured and non-injured drivers, and for drivers aged between 26 and 65 years. Crash culpability was found to be significantly associated with cell phone use by drivers, increasing the odds of a culpable crash by 70% compared with drivers who did not use a cell phone. This increased risk was particularly high for middle-aged drivers.

Observed and unobserved correlation between crash avoidance manoeuvers and crash severity

DEFF Research Database (Denmark)

Kaplan, Sigal; Prato, Carlo Giacomo

2015-01-01

Understanding drivers’ responses to critical events, analyzing drivers’ abilities to perform corrective manoeuvers, and investigating the correlation between these manoeuvers and crash severity provide the opportunity of increasing the knowledge about how to avoid crash occurrence or at least mit...

Statistical analysis of vehicle crashes in Mississippi based on crash data from 2010 to 2014.

Science.gov (United States)

2017-08-15

Traffic crash data from 2010 to 2014 were collected by Mississippi Department of Transportation (MDOT) and extracted for the study. Three tasks were conducted in this study: (1) geographic distribution of crashes; (2) descriptive statistics of crash ...

Construct exploit constraint in crash analysis by bypassing canary

Science.gov (United States)

Huang, Ning; Huang, Shuguang; Huang, Hui; Chang, Chao

2017-08-01

Selective symbolic execution is a common program testing technology. Developed on the basis of it, some crash analysis systems are often used to test the fragility of the program by constructing exploit constraints, such as CRAX. From the study of crash analysis based on symbolic execution, this paper find that this technology cannot bypass the canary stack protection mechanisms. This paper makes the improvement uses the API hook in Linux. Experimental results show that the use of API hook can effectively solve the problem that crash analysis cannot bypass the canary protection.

The October 2014 United States Treasury bond flash crash and the contributory effect of mini flash crashes.

Directory of Open Access Journals (Sweden)

Zachary S Levine

Full Text Available We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention.

The October 2014 United States Treasury bond flash crash and the contributory effect of mini flash crashes.

Science.gov (United States)

Levine, Zachary S; Hale, Scott A; Floridi, Luciano

2017-01-01

We investigate the causal uncertainty surrounding the flash crash in the U.S. Treasury bond market on October 15, 2014, and the unresolved concern that no clear link has been identified between the start of the flash crash at 9:33 and the opening of the U.S. equity market at 9:30. We consider the contributory effect of mini flash crashes in equity markets, and find that the number of equity mini flash crashes in the three-minute window between market open and the Treasury Flash Crash was 2.6 times larger than the number experienced in any other three-minute window in the prior ten weekdays. We argue that (a) this statistically significant finding suggests that mini flash crashes in equity markets both predicted and contributed to the October 2014 U.S. Treasury Bond Flash Crash, and (b) mini-flash crashes are important phenomena with negative externalities that deserve much greater scholarly attention.

Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach.

Science.gov (United States)

Kaplan, Sigal; Prato, Carlo Giacomo

2012-01-01

The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. The analysis is conducted by means of a mixed logit model that represents the selection among 5 emergency lateral and speed control maneuvers (i.e., "no avoidance maneuvers," "braking," "steering," "braking and steering," and "other maneuvers) while accommodating correlations across maneuvers and heteroscedasticity. Data for the analysis were retrieved from the General Estimates System (GES) crash database for the year 2009 by considering drivers for which crash avoidance maneuvers are known. The results show that (1) the nature of the critical event that made the crash imminent greatly influences the choice of crash avoidance maneuvers, (2) women and elderly have a relatively lower propensity to conduct crash avoidance maneuvers, (3) drowsiness and fatigue have a greater negative marginal effect on the tendency to engage in crash avoidance maneuvers than alcohol and drug consumption, (4) difficult road conditions increase the propensity to perform crash avoidance maneuvers, and (5) visual obstruction and artificial illumination decrease the probability to carry out crash avoidance maneuvers. The results emphasize the need for public awareness campaigns to promote safe driving style for senior drivers and warning about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing

Airplane crash

International Nuclear Information System (INIS)

Brunner, P.

1975-01-01

In May, 1974, a severe airplane crash occurred near Springfield, llinois; the crew of three and a courier were killed. The plane was carrying a large container of controlled water with a slight amount of 60 Co. A survey of the crash site by Air Force detectives and the radiological assistance team from Wright--Patterson Air Force Base indicated no radioactivity. Experiences of the incident were used to develop guidelines for future emergency preparedness

Repeatability study of replicate crash tests: A signal analysis approach.

Science.gov (United States)

Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

2017-10-03

To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test

Creating pedestrian crash scenarios in a driving simulator environment.

Science.gov (United States)

Chrysler, Susan T; Ahmad, Omar; Schwarz, Chris W

2015-01-01

adjust time to arrival triggers for the pedestrian actions. This article discusses the rationale behind creating the simulator scenarios and some of the procedural considerations for conducting this type of research. Crash analyses can be used to construct test scenarios for driver behavior evaluations using driving simulators. By considering trajectories, roadway, and environmental conditions of real-world crashes, representative virtual scenarios can serve as safe test beds for advanced driver assistance systems. The results of such research can be used to inform pedestrian crash avoidance/mitigation systems by identifying driver error, driver response time, and driver response choice (i.e., steering vs. braking).

Road crash costs.

NARCIS (Netherlands)

2010-01-01

Road crashes result in all kinds of social costs, such as medical costs, production loss, human losses, property damage, settlement costs and costs due to congestion. Studies into road crash costs and their trends are carried out quite regularly. In 2009, the costs amounted to € 12.5 billion, or

Reporting on cyclist crashes in Australian newspapers.

Science.gov (United States)

Boufous, Soufiane; Aboss, Ahmad; Montgomery, Victoria

2016-10-01

To assess information on cyclist crashes reported in Australian newspapers. The Factiva news archive was searched for articles on cyclist crashes published in major Australian newspapers between 2010 and 2013. Information on the circumstances of cyclist crashes were extracted and coded. A total of 160 cyclist crashes were covered by 198 newspaper articles, with 44% of crashes resulting in cyclist fatalities. Crashes reported by more than one newspaper were more likely to involve public figures or protracted court cases. Individual characteristics of cyclists as well as the location of the crash were reported for more than 80% of crashes. The road user at fault was reported for more than half of crashes. In contrast, information on helmet use, alcohol and cycling lanes was mentioned for only about 10% of crashes. Fewer than one in five articles mentioned prevention strategies including education campaigns, legislative and infrastructure changes. Australian newspapers tend to focus on the most dramatic and more 'newsworthy' aspects of cyclist crashes. Cycling advocates need to work with journalists to improve the quality of this coverage. Better communication between cycling advocates and journalists is likely to have a positive impact on the safety and the uptake of cycling in the community. © 2016 Public Health Association of Australia.

Motor Carrier Crash Data -

Data.gov (United States)

Department of Transportation — Contains data on large trucks and buses involved in Federally reportable crashes as per Title 49 U.S.C. Part 390.5 (crashes involving a commercial motor vehicle, and...

Patterns of severe injury in pediatric car crash victims: Crash Injury Research Engineering Network database.

Science.gov (United States)

Brown, J Kristine; Jing, Yuezhou; Wang, Stewart; Ehrlich, Peter F

2006-02-01

Motor vehicle crashes (MVCs) account for 50% of pediatric trauma. Safety improvements are typically tested with child crash dummies using an in vitro model. The Crash Injury Research Engineering Network (CIREN) provides an in vivo validation process. Previous research suggest that children in lateral crashes or front-seat locations have higher Injury Severity Scale scores and lower Glasgow Coma Scale scores than those in frontal-impact crashes. However, specific injury patterns and crash characteristics have not been characterized. Data were collected from the CIREN multidisciplinary crash reconstruction network (10 pediatric trauma centers). Injuries were examined with regard to crash direction (frontal/lateral), restraint use, seat location, and change in velocity at impact (DeltaV). Injuries were limited to Abbreviated Injury Scale (AIS) scores of 3 or higher and included head, thoracic, abdominal, pelvic, spine, and long bone (orthopedic) injuries. Standard age groupings (0-4, 5-9, 10-14, and 15-18 years) were used. Statistical analyses used Fisher's Exact test and multiple logistic regressions. Four hundred seventeen MVCs with 2500 injuries were analyzed (males = 219, females = 198). Controlling for DeltaV and age, children in lateral-impact crashes (n = 232) were significantly more likely to suffer severe injuries to the head and thorax as compared with children in frontal crashes (n = 185), who were more likely to suffer severe spine and orthopedic injuries. Children in a front-seat (n = 236) vs those in a back-seat (n = 169) position had more injuries to the thoracic (27% vs 17%), abdominal (21% vs 13%), pelvic (11% vs 1%), and orthopedic (28% vs 10%) regions (P < .05 for all). Seat belts were protective for pelvic (5% vs 12% unbelted) and orthopedic (15% vs 40%) injuries (odds ratio = 3, P < .01 for both). A reproducible pattern of injury is noted for children involved in lateral-impact crashes characterized by head and chest injuries. The Injury Severity

Neighborhood Influences on Vehicle-Pedestrian Crash Severity.

Science.gov (United States)

Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas

2017-12-01

Socioeconomic factors are known to be contributing factors for vehicle-pedestrian crashes. Although several studies have examined the socioeconomic factors related to the location of the crashes, limited studies have considered the socioeconomic factors of the neighborhood where the road users live in vehicle-pedestrian crash modelling. This research aims to identify the socioeconomic factors related to both the neighborhoods where the road users live and where crashes occur that have an influence on vehicle-pedestrian crash severity. Data on vehicle-pedestrian crashes that occurred at mid-blocks in Melbourne, Australia, was analyzed. Neighborhood factors associated with road users' residents and location of crash were investigated using boosted regression tree (BRT). Furthermore, partial dependence plots were applied to illustrate the interactions between these factors. We found that socioeconomic factors accounted for 60% of the 20 top contributing factors to vehicle-pedestrian crashes. This research reveals that socioeconomic factors of the neighborhoods where the road users live and where the crashes occur are important in determining the severity of the crashes, with the former having a greater influence. Hence, road safety countermeasures, especially those focussing on the road users, should be targeted at these high-risk neighborhoods.

Narrative text analysis to identify technologies to prevent motor vehicle crashes: examples from military vehicles.

Science.gov (United States)

Pollack, Keshia M; Yee, Nathan; Canham-Chervak, Michelle; Rossen, Lauren; Bachynski, Kathleen E; Baker, Susan P

2013-02-01

The purpose of this research is to describe the leading circumstances of military vehicle crashes to guide prioritization and implementation of crash avoidance and/or warning technologies. A descriptive study using narrative text analysis on 3,944 military vehicle crash narratives. Crash data on drivers, from 2001 to 2006, were assembled from the U.S. Army Combat Readiness/Safety Center. Reviewers collected information on the circumstances of crashes and determined if vehicle technology could have prevented the crash. Nearly 98% of the crashes were nonfatal; 63% occurred in the U.S. and 24% in Iraq. Among crash events where the direction of the impact was recorded, 32% were to the front of the vehicle and 16% involved a vehicle being rear-ended. Rollovers were mentioned in 20% of the narratives. Technology was determined to have the potential to prevent 26% of the crashes, with the forward collision warning system, rear end collision avoidance, emergency brake assistance, and rollover stability control system likely to have the greatest impacts. Some technologies available for civilian vehicles may prevent certain military crash circumstances. The results of this research are significant in light of ongoing global military operations that rely on military vehicles. Improving the preventive technology featured on military vehicles may be an effective strategy to reduce the occurrence of military crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.

From “Crash!” to Crash: Adapting the Adaptation

Directory of Open Access Journals (Sweden)

Ljubica Matek

2017-12-01

Full Text Available The paper focuses on J.G. Ballard’s various adaptations of his own material related to the issue of the sexual and sensual nature of an automobile crash, and suggests that adaptation is one of the key methods in art and literature which can be used as a means of contemplating and developing various aesthetic and political ideas. Ballard’s short story “Crash!” was first published in the ICA’s (Institute of Contemporary Arts Eventsheet in February 1969, and later became a chapter of his experimental novel The Atrocity Exhibition (1970. At the same time, Ballard adapts the idea into the “Crashed Cars” exhibition (1970 in London. The short story was then adapted into a short film, Crash!, directed by Harley Cokeliss (1971 and starring Ballard himself, to be finally adapted into the novel Crash (1973. Ballard’s adaptation of his initial ideas across literary forms and media testifies to the importance of adaptation as a process and method of creating art. Thus, rather than suggesting that adaptations merely “breathe life” into the written word, the paper points to the conclusion that the form and content are mutually influential and that, in this case, the novel itself is an adaptation, rather than a hypotext (which it becomes in 1996 to David Cronenberg as he adapts it to film. The complexity of the relationship between the source text and its many adaptations has already contributed to the deconstruction, in Derrida’s terms, of the hierarchy (opposition between the original and the copy. Rather, Ballard’s crossmedial and transmedial adaptations of his own ideas show how, as Ray would suggest, an adaptation cites the source and grafts it into a new context, giving it a new function, both aesthetic and political.

Feasibility of a web-based system for police crash report review and information recording.

Science.gov (United States)

2016-04-01

Police crash reports include useful additional information that is not available in crash summary records. : This information may include police sketches and narratives and is often needed for detailed site-specific : safety analysis. In addition, so...

Cross-country VFR crashes: pilot and contextual factors.

Science.gov (United States)

O'Hare, David; Owen, Douglas

2002-04-01

General Aviation (GA) cross-country crashes, particularly those involving weather, continue to be a major source of fatalities, with a fatality rate more than four times greater than for GA crashes in general. There has been much speculation and little solid evidence on the causes of these crashes. We have designed a program of laboratory and database research into the causes of cross-country weather-related crashes including an analysis of air crashes in New Zealand between 1988 and 2000. There were 1308 reported occurrences in this period. We examined in detail 77 crashes where it could be determined that the aircraft was on a cross-country flight. In our first analysis we compared the characteristics of crashes that occurred in response to externally driven failures with crashes where the aircraft continued to be flown at the pilot's discretion up until the point of the crash. Clear differences were found for visibility, altitude, crash severity, and for several pilot characteristics. These differences are highly consistent with those found for previous research on pilot characteristics and crash involvement. In the second analysis we made comparisons between the weather-related and nonweather-related crashes in the discretionary control group and between subcategories of weather-related crashes. These data show that weather-related crashes occur further into the flight and closer to the planned destination than other kinds of cross-country crashes in GA. Pilots involved in these crashes are younger and have more recent flight time than pilots involved in other crashes. Their increased involvement cannot be explained simply by exposure (flight-time) but must be due to other factors.

Homogenization of Vehicle Fleet Frontal Crash Pulses from 2000–2010

Science.gov (United States)

Locey, Caitlin M.; Garcia-Espana, J. Felipe; Toh, Akira; Belwadi, Aditya; Arbogast, Kristy B.; Maltese, Matthew R.

2012-01-01

Full-scale vehicle crash tests are performed globally to assess vehicle structure and restraint system performance. The crash pulse, captured by accelerometers mounted within the occupant compartment, measures the motion of the vehicle during the impact event. From an occupant’s perspective, the crash pulse is the inertial event to which the vehicle’s restraint systems must respond in order to mitigate the forces and accelerations that act on a passenger, and thus reduce injury risk. The objective of this study was to quantify the characteristics of crash pulses for different vehicle types in the contemporary North American fleet, and delineate current trends in crash pulse evolution. NHTSA and Transport Canada crash test databases were queried for full-frontal rigid barrier crash tests of passenger vehicles model year 2000–2010 with impact angle equaling zero degrees. Acceleration-time histories were analyzed for all accelerometers attached to the vehicle structure within the occupant compartment. Custom software calculated the following crash pulse characteristics (CPCs): peak deceleration, time of peak deceleration, onset rate, pulse duration, and change in velocity. Vehicle body types were classified by adapting the Highway Loss Data Institute (HLDI) methodology, and vehicles were assigned a generation start year in place of model year in order to more accurately represent structural change over time. 1094 vehicle crash tests with 2795 individual occupant compartment-mounted accelerometers were analyzed. We found greater peak decelerations and and shorter pulse durations across multiple vehicle types in newer model years as compared to older. For midsize passenger cars, large passenger cars, and large SUVs in 56 km/h rigid barrier tests, maximum deceleration increased by 0.40, 0.96, and 1.57 g/year respectively, and pulse duration decreased by 0.74, 1.87, and 2.51 ms/year. We also found that the crash pulse characteristics are becoming more homogeneous in

Sleep-related vehicle crashes on low speed roads.

Science.gov (United States)

Filtness, A J; Armstrong, K A; Watson, A; Smith, S S

2017-02-01

Very little is known about the characteristics of sleep related (SR) crashes occurring on low speed roads compared with current understanding of the role of sleep in crashes occurring on high speed roads e.g. motorways. To address this gap, analyses were undertaken to identify the differences and similarities between (1) SR crashes occurring on roads with low (≤60km/h) and high (≥100km/h) speed limits, and (2) SR crashes and not-SR crashes occurring on roads with low speed limits. Police reports of all crashes occurring on low and high speed roads over a ten year period between 2000 and 2009 were examined for Queensland, Australia. Attending police officers identified all crash attributes, including 'fatigue/fell asleep', which indicates that the police believe the crash to have a causal factor relating to falling asleep, sleepiness due to sleep loss, time of day, or fatigue. Driver or rider involvement in crashes was classified as SR or not-SR. All crash-associated variables were compared using Chi-square tests (Cramer's V=effect size). A series of logistic regression was performed, with driver and crash characteristics as predictors of crash category. A conservative alpha level of 0.001 determined statistical significance. There were 440,855 drivers or riders involved in a crash during this time; 6923 (1.6%) were attributed as SR. SR crashes on low speed roads have similar characteristics to those on high speed roads with young (16-24y) males consistently over represented. SR crashes on low speed roads are noticeably different to not-SR crashes in the same speed zone in that male and young novice drivers are over represented and outcomes are more severe. Of all the SR crashes identified, 41% occurred on low speed roads. SR crashes are not confined to high speed roads. Low speed SR crashes warrant specific investigation because they occur in densely populated areas, exposing a greater number of people to risk and have more severe outcomes than not-SR crashes

Not just a rural occurrence: differences in agricultural equipment crash characteristics by rural-urban crash site and proximity to town.

Science.gov (United States)

Harland, Karisa K; Greenan, Mitchell; Ramirez, Marizen

2014-09-01

Although approximately one-third of agricultural equipment-related crashes occur near town, these crashes are thought to be a rural problem. This analysis examines differences between agricultural equipment-related crashes by their urban-rural distribution and distance from a town. Agricultural equipment crashes were collected from nine Midwest Departments of Transportation (2005-2008). Crash zip code was assigned as urban or rural (large, small and isolated) using Rural-Urban Commuting Areas. Crash proximity to a town was estimated with ArcGIS. Multivariable logistic regression was used to estimate the odds of crashing in an urban versus rural zip codes and across rural gradients. ANOVA analysis estimated mean distance (miles) from a crash site to a town. Over four years, 4444 crashes involved agricultural equipment. About 30% of crashes occurred in urban zip codes. Urban crashes were more likely to be non-collisions (aOR=1.69[1.24-2.30]), involve ≥2 vehicles (2 vehicles: aOR=1.58[1.14-2.20], 3+ vehicles: aOR=1.68[0.98-2.88]), occur in a town (aOR=2.06[1.73-2.45]) and within one mile of a town (aOR=1.65[1.40-1.95]) than rural crashes. The proportion of crashes within a town differed significantly across rural gradients (Purban-rural distribution (Pagricultural equipment are unexpectedly common in urban areas and near towns and cities. Education among all roadway users, increased visibility of agricultural equipment and the development of complete rural roads are needed to increase road safety and prevent agricultural equipment-related crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of Test and Finite Element Analysis for Two Full-Scale Helicopter Crash Tests

Science.gov (United States)

Annett, Martin S.; Horta,Lucas G.

2011-01-01

Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.

Commercial truck crash injury severity analysis using gradient boosting data mining model.

Science.gov (United States)

Zheng, Zijian; Lu, Pan; Lantz, Brenda

2018-06-01

Truck crashes contribute to a large number of injuries and fatalities. This study seeks to identify the contributing factors affecting truck crash severity using 2010 to 2016 North Dakota and Colorado crash data provided by the Federal Motor Carrier Safety Administration. To fulfill a gap of previous studies, broad considerations of company and driver characteristics, such as company size and driver's license class, along with vehicle types and crash characteristics are researched. Gradient boosting, a data mining technique, is applied to comprehensively analyze the relationship between crash severities and a set of heterogeneous risk factors. Twenty five variables were tested and 22 of them are identified as significant variables contributing to injury severities, however, top 11 variables account for more than 80% of injury forecasting. The relative variable importance analysis is conducted and furthermore marginal effects of all contributing factors are also illustrated in this research. Several factors such as trucking company attributes (e.g., company size), safety inspection values, trucking company commerce status (e.g., interstate or intrastate), time of day, driver's age, first harmful events, and registration condition are found to be significantly associated with crash injury severity. Even though most of the identified contributing factors are significant for all four levels of crash severity, their relative importance and marginal effect are all different. For the first time, trucking company and driver characteristics are proved to have significant impact on truck crash injury severity. Some of the results in this study reinforce previous studies' conclusions. Findings in this study can be helpful for transportation agencies to reduce injury severity, and develop efficient strategies to improve safety. Copyright © 2018 National Safety Council and Elsevier Ltd. All rights reserved.

Cannabis and crash responsibility while driving below the alcohol per se legal limit.

Science.gov (United States)

Romano, Eduardo; Voas, Robert B; Camp, Bayliss

2017-11-01

There is a growing interest in how extensively the use of marijuana by drivers relates to crash involvement. While cognitive, lab-based studies are consistent in showing that the use of cannabis impairs driving tasks, epidemiological, field-based studies have been inconclusive regarding whether cannabis use causes an increased risk of accidents. There is ample evidence that the presence of cannabis among drivers with a BAC≥0.08g/dL highly increases the likelihood of a motor vehicle crash. Less clear, however, is the contribution of cannabis to crash risk when drivers have consumed very little or no alcohol. This effort addresses this gap in knowledge. We took advantage of a unique database that merged fatal crashes in the California Statewide Integrated Traffic Records System (SWITRS) and the Fatality Analysis Reporting System (FARS), which allows for a precise identification of crash responsibility. To account for recent increase in lab testing, we restricted our sample to cover only the years 1993-2009. A total of 4294 drivers were included in the analyses. Descriptive analyses and logistic regressions were run to model the contribution of alcohol and drugs to the likelihood of being responsible in a fatal crash. We found evidence that compared with drivers negative for alcohol and cannabis, the presence of cannabis elevates crash responsibility in fatal crashes among drivers at zero BACs (OR=1.89) and with 0cannabis on fatal crashes, in particular in the absence of alcohol, are needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Heavy Vehicle Crash Characteristics in Oman; 2009–2011

Directory of Open Access Journals (Sweden)

Islam Al-Bulushi

2015-05-01

Full Text Available In recent years, Oman has seen a shift in the burden of diseases towards road accidents. The main objective of this paper, therefore, is to describe key characteristics of heavy vehicle crashes in Oman and identify the key driving behaviours that influence fatality risks. Crash data from January 2009 to December 2011 were examined and it was found that, of the 22,543 traffic accidents that occurred within this timeframe, 3,114 involved heavy vehicles. While the majority of these crashes were attributed to driver behaviours, a small proportion was attributed to other factors. The results of the study indicate that there is a need for a more thorough crash investigation process in Oman. Future research should explore the reporting processes used by the Royal Oman Police, cultural influences on heavy vehicle operations in Oman and improvements to the current licensing system.

Understanding fatal older road user crash circumstances and risk factors.

Science.gov (United States)

Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith

2018-02-28

This study used medicolegal data to investigate fatal older road user (ORU) crash circumstances and risk factors relating to four key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners Court of Victoria's Surveillance Database was searched to identify coronial records with at least one deceased ORU in the state of Victoria, Australia, for 2013-2014. Information relating to the ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. The average rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI] 6.0-10.2), which was more than double the average rate of fatal middle-aged road user crashes (3.6, 95% CI 2.5-4.6). There was a significant relationship between age group and deceased road user type (χ 2 (15, N = 226) = 3.56, p road" (87.0%), on roads that were paved (94.2%), dry (74.2%), and had light traffic volume (38.3%). Road user error was identified by the police and/or coroner for the majority of fatal ORU crashes (57.9%), with a significant proportion of deceased ORU deemed to have "misjudged" (40.9%) or "failed to yield" (37.9%). Road user error was the most significant risk factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the Victorian road system to fully accommodate road user errors. Initiatives related to safer roads and roadsides, vehicles, and speed zones, as well as behavioral approaches, are key areas of priority for targeted activity to prevent fatal older road user crashes in the future.

The invisible hand and the rational agent are behind bubbles and crashes

International Nuclear Information System (INIS)

Galam, Serge

2016-01-01

The 2000 dot-com crash and the 2008 subprime crisis have fueled the belief that the two classical paradigms of economics, the invisible hand and the rational agent, are not well appropriate to describe market dynamics and should be abandoned at the benefit of alternative new theoretical concepts. At odd with such a view, using a simple model of choice dynamics from sociophysics, the invisible hand and the rational agent paradigms are given a new legitimacy. Indeed, it is sufficient to introduce the holding of a few intermediate mini market aggregations by agents sharing their own private information, to recenter the invisible hand and the rational agent at the heart of market self regulation. An elasticity is discovered in the market efficiency mechanism due to the existence of an agent collective anticipation. This elasticity is shown to create spontaneous bubbles, which are rationally founded. At the same time, crashes occur at once when the limit of elasticity is reached. Plasticity can also be achieved through a combination of a crash with a sudden shift of the collective anticipation. Although the findings disclose a path to put an end to the bubble-crash phenomena, it is argued to be rationally not feasible. Bubbles and crashes are thus an intrinsic internal part of classical economics.

Factors associated with civilian drivers involved in crashes with emergency vehicles.

Science.gov (United States)

Drucker, Christopher; Gerberich, Susan G; Manser, Michael P; Alexander, Bruce H; Church, Timothy R; Ryan, Andrew D; Becic, Ensar

2013-06-01

Motor vehicle crashes involving civilian and emergency vehicles (EVs) have been a known problem that contributes to fatal and nonfatal injuries; however, characteristics associated with civilian drivers have not been examined adequately. This study used data from The National Highway Traffic Safety Administration's Fatality Analysis Reporting System and the National Automotive Sampling System General Estimates System to identify driver, roadway, environmental, and crash factors, and consequences for civilian drivers involved in fatal and nonfatal crashes with in-use and in-transport EVs. In general, drivers involved in emergency-civilian crashes (ECCs) were more often driving: straight through intersections (vs. same direction) of four-points or more (vs. not at intersection); where traffic signals were present (vs. no traffic control device); and at night (vs. midday). For nonfatal ECCs, drivers were more often driving: distracted (vs. not distracted); with vision obstructed by external objects (vs. no obstruction); on dark but lighted roads (vs. daylight); and in opposite directions (vs. same directions) of the EVs. Consequences included increased risk of injury (vs. no injury) and receiving traffic violations (vs. no violation). Fatal ECCs were associated with driving on urban roads (vs. rural), although these types of crashes were less likely to occur on dark roads (vs. daylight). The findings of this study suggest drivers may have difficulties in visually detecting EVs in different environments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modeling crash injury severity by road feature to improve safety.

Science.gov (United States)

Penmetsa, Praveena; Pulugurtha, Srinivas S

2018-01-02

The objective of this research is 2-fold: to (a) model and identify critical road features (or locations) based on crash injury severity and compare it with crash frequency and (b) model and identify drivers who are more likely to contribute to crashes by road feature. Crash data from 2011 to 2013 were obtained from the Highway Safety Information System (HSIS) for the state of North Carolina. Twenty-three different road features were considered, analyzed, and compared with each other as well as no road feature. A multinomial logit (MNL) model was developed and odds ratios were estimated to investigate the effect of road features on crash injury severity. Among the many road features, underpass, end or beginning of a divided highway, and on-ramp terminal on crossroad are the top 3 critical road features. Intersection crashes are frequent but are not highly likely to result in severe injuries compared to critical road features. Roundabouts are least likely to result in both severe and moderate injuries. Female drivers are more likely to be involved in crashes at intersections (4-way and T) compared to male drivers. Adult drivers are more likely to be involved in crashes at underpasses. Older drivers are 1.6 times more likely to be involved in a crash at the end or beginning of a divided highway. The findings from this research help to identify critical road features that need to be given priority. As an example, additional advanced warning signs and providing enlarged or highly retroreflective signs that grab the attention of older drivers may help in making locations such as end or beginning of a divided highway much safer. Educating drivers about the necessary skill sets required at critical road features in addition to engineering solutions may further help them adopt safe driving behaviors on the road.

Crash Fatality Rates After Recreational Marijuana Legalization in Washington and Colorado.

Science.gov (United States)

Aydelotte, Jayson D; Brown, Lawrence H; Luftman, Kevin M; Mardock, Alexandra L; Teixeira, Pedro G R; Coopwood, Ben; Brown, Carlos V R

2017-08-01

To evaluate motor vehicle crash fatality rates in the first 2 states with recreational marijuana legalization and compare them with motor vehicle crash fatality rates in similar states without recreational marijuana legalization. We used the US Fatality Analysis Reporting System to determine the annual numbers of motor vehicle crash fatalities between 2009 and 2015 in Washington, Colorado, and 8 control states. We compared year-over-year changes in motor vehicle crash fatality rates (per billion vehicle miles traveled) before and after recreational marijuana legalization with a difference-in-differences approach that controlled for underlying time trends and state-specific population, economic, and traffic characteristics. Pre-recreational marijuana legalization annual changes in motor vehicle crash fatality rates for Washington and Colorado were similar to those for the control states. Post-recreational marijuana legalization changes in motor vehicle crash fatality rates for Washington and Colorado also did not significantly differ from those for the control states (adjusted difference-in-differences coefficient = +0.2 fatalities/billion vehicle miles traveled; 95% confidence interval = -0.4, +0.9). Three years after recreational marijuana legalization, changes in motor vehicle crash fatality rates for Washington and Colorado were not statistically different from those in similar states without recreational marijuana legalization. Future studies over a longer time remain warranted.

Conscientious personality and young drivers’ crash risk

OpenAIRE

Ehsani, Johnathon P.; Li, Kaigang; Simons-Morton, Bruce; Tree-McGrath, Cheyenne Fox; Perlus, Jessamyn; O’Brien, Fearghal; Klauer, Sheila G.

2015-01-01

Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior, and crashes and near-crashes, using naturalistic driving research methods. Method: Participants' driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes...

Crashes and near-crashes on horizontal curves along rural two-lane highways: Analysis of naturalistic driving data.

Science.gov (United States)

Wang, Bo; Hallmark, Shauna; Savolainen, Peter; Dong, Jing

2017-12-01

Prior research has shown the probability of a crash occurring on horizontal curves to be significantly higher than on similar tangent segments, and a disproportionally higher number of curve-related crashes occurred in rural areas. Challenges arise when analyzing the safety of horizontal curves due to imprecision in integrating information as to the temporal and spatial characteristics of each crash with specific curves. The second Strategic Highway Research Program(SHRP 2) conducted a large-scale naturalistic driving study (NDS),which provides a unique opportunity to better understand the contributing factors leading to crash or near-crash events. This study utilizes high-resolution behavioral data from the NDS to identify factors associated with 108 safety critical events (i.e., crashes or near-crashes) on rural two-lane curves. A case-control approach is utilized wherein these events are compared to 216 normal, baseline-driving events. The variables examined in this study include driver demographic characteristics, details of the traffic environment and roadway geometry, as well as driver behaviors such as in-vehicle distractions. Logistic regression models are estimated to discern those factors affecting the likelihood of a driver being crash-involved. These factors include high-risk behaviors, such as speeding and visual distractions, as well as curve design elements and other roadway characteristics such as pavement surface conditions. This paper successfully integrated driver behavior, vehicle characteristics, and roadway environments into the same model. Logistic regression model was found to be an effective way to investigate crash risks using naturalistic driving data. This paper revealed a number of contributing factors to crashes on rural two-lane curves, which has important implications in traffic safety policy and curve geometry design. This paper also discussed limitations and lessons learned from working with the SHRP 2 NDS data. It will benefit

Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes

OpenAIRE

Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu

2013-01-01

Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with ...

Omitted variable bias in crash reduction factors.

Science.gov (United States)

2015-09-01

Transportation planners and traffic engineers are increasingly turning to crash reduction factors to evaluate changes in road : geometric and design features in order to reduce crashes. Crash reduction factors are typically estimated based on segment...

Understanding traffic crash under-reporting

DEFF Research Database (Denmark)

Janstrup, Kira Hyldekær; Kaplan, Sigal; Hels, Tove

2016-01-01

Objective: This study aligns to the body of research dedicated to estimating the underreporting of road crash injuries and adds the perspective of understanding individual and crash factors contributing to the decision to report a crash to the police, the hospital, or both. Method: This study foc...... policy measures aimed at increasing the reporting rate by targeting specific road user groups (e.g., males, young road users) or specific situational factors (e.g., slight injuries, arm injuries, leg injuries, weekend)....

The relationship between impaired driving crashes and beliefs about impaired driving: do residents in high crash rate counties have greater concerns about impaired driving?

Science.gov (United States)

Beck, Kenneth H; Yan, Alice F; Wang, Min Qi; Kerns, Timothy J; Burch, Cynthia A

2009-04-01

The purpose of this investigation was to examine the relationship between impaired driving crashes and public beliefs and concerns about impaired driving across each of Maryland's twenty-four counties (including Baltimore City). It was hypothesized that residents of counties that experience higher impaired driving crashes would express more concerns about impaired driving and perceive more risks about driving impaired than residents of counties that have lower rates of impaired driving. Data for alcohol impaired driving crashes were obtained for the years 2004-2006. These data were compared to public opinion data that was obtained annually by random-digit-dial telephone surveys from 2004 to 2007. Concerns about drunk driving as well as perceptions of the likelihood of being stopped by the police if one were to drive after having too much to drink were related to counties with higher serious impaired driving crash rates, as were perceptions that the police and the legal system were too lenient. Perceptions about the likelihood of being stopped by the police were higher in those counties with more impaired driving enforcement activity. Perceptions of concern appear to be shaped more by crash exposure than enforcement activity. Campaigns that address impaired driving prevention should substantially increase enforcement, strengthen the adjudication process of impaired drivers, and emphasize the potential seriousness of drinking-driving crashes in their promotional activities.

AP English language & composition crash course

CERN Document Server

Hogue, Dawn

2012-01-01

AP English Language & Composition Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP English Language & Composition Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP English Language & Composition course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valua

Large truck and bus crash facts, 2010.

Science.gov (United States)

2012-09-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2010. Selected crash statistics on passenger : vehicles are also presen...

Large truck and bus crash facts, 2012.

Science.gov (United States)

2014-06-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2012. Selected crash statistics on passenger vehicles are also presented ...

Large truck and bus crash facts, 2013.

Science.gov (United States)

2015-04-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2013. Selected crash statistics on passenger vehicles are also presented ...

Large truck and bus crash facts, 2009.

Science.gov (United States)

2011-10-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2009. Selected crash statistics on passenger : vehicles are also presen...

Large truck and bus crash facts, 2011.

Science.gov (United States)

2013-10-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2011. Selected crash statistics on passenger : vehicles are also presen...

Real time control of restraint systems in frontal crashes

NARCIS (Netherlands)

Griotto, G.; Lemmen, P.P.M.; Eijnden, E.A.C. van den; Leijsen, A.C.P. van; Schie, C. van; Cooper, J.

2007-01-01

It is generally accepted that the targets for fatality reduction in car accidents set by Governments in Europe, USA and Japan can only be met by using advanced technologies that will include a broad range of sensors to monitor the crash likelihood and severity, vehicle condition, occupant type and

Macro-level vulnerable road users crash analysis: A Bayesian joint modeling approach of frequency and proportion.

Science.gov (United States)

Cai, Qing; Abdel-Aty, Mohamed; Lee, Jaeyoung

2017-10-01

This study aims at contributing to the literature on pedestrian and bicyclist safety by building on the conventional count regression models to explore exogenous factors affecting pedestrian and bicyclist crashes at the macroscopic level. In the traditional count models, effects of exogenous factors on non-motorist crashes were investigated directly. However, the vulnerable road users' crashes are collisions between vehicles and non-motorists. Thus, the exogenous factors can affect the non-motorist crashes through the non-motorists and vehicle drivers. To accommodate for the potentially different impact of exogenous factors we convert the non-motorist crash counts as the product of total crash counts and proportion of non-motorist crashes and formulate a joint model of the negative binomial (NB) model and the logit model to deal with the two parts, respectively. The formulated joint model is estimated using non-motorist crash data based on the Traffic Analysis Districts (TADs) in Florida. Meanwhile, the traditional NB model is also estimated and compared with the joint model. The result indicates that the joint model provides better data fit and can identify more significant variables. Subsequently, a novel joint screening method is suggested based on the proposed model to identify hot zones for non-motorist crashes. The hot zones of non-motorist crashes are identified and divided into three types: hot zones with more dangerous driving environment only, hot zones with more hazardous walking and cycling conditions only, and hot zones with both. It is expected that the joint model and screening method can help decision makers, transportation officials, and community planners to make more efficient treatments to proactively improve pedestrian and bicyclist safety. Published by Elsevier Ltd.

Religion and stock price crash risk: Evidence

Directory of Open Access Journals (Sweden)

Wenfei Li

2016-09-01

Full Text Available This paper investigates whether religious traditions influence firm-specific crash risk in China. Using a sample of A-share listed firms from 2003 to 2013, we provide evidence that the more intense the religious environment, the lower the stock price crash risk, implying that religion plays an important role in Chinese corporate governance. Further, we find that (1 religion affects stock price crash risk by reducing earnings management and the management perk problem; (2 different religions have different effects, and Taoism, in particular, is unrelated to crash risk; and (3 the effects of religion are more pronounced with higher quality corporate governance and a stronger legal environment. Religion constrains the management agency problem, thus reducing stock price crash risk in China. Our paper enriches the literature on stock price crash risk and religion, and on new economic geography.

Crash Prediction and Risk Evaluation Based on Traffic Analysis Zones

Directory of Open Access Journals (Sweden)

Cuiping Zhang

2014-01-01

Full Text Available Traffic safety evaluation for traffic analysis zones (TAZs plays an important role in transportation safety planning and long-range transportation plan development. This paper aims to present a comprehensive analysis of zonal safety evaluation. First, several criteria are proposed to measure the crash risk at zonal level. Then these criteria are integrated into one measure-average hazard index (AHI, which is used to identify unsafe zones. In addition, the study develops a negative binomial regression model to statistically estimate significant factors for the unsafe zones. The model results indicate that the zonal crash frequency can be associated with several social-economic, demographic, and transportation system factors. The impact of these significant factors on zonal crash is also discussed. The finding of this study suggests that safety evaluation and estimation might benefit engineers and decision makers in identifying high crash locations for potential safety improvements.

Overview of the Transport Rotorcraft Airframe Crash Testbed (TRACT) Full Scale Crash Tests

Science.gov (United States)

Annett, Martin; Littell, Justin

2015-01-01

The Transport Rotorcraft Airframe Crash Testbed (TRACT) full-scale tests were performed at NASA Langley Research Center's Landing and Impact Research Facility in 2013 and 2014. Two CH-46E airframes were impacted at 33-ft/s forward and 25-ft/s vertical combined velocities onto soft soil, which represents a severe, but potentially survivable impact scenario. TRACT 1 provided a baseline set of responses, while TRACT 2 included retrofits with composite subfloors and other crash system improvements based on TRACT 1. For TRACT 2, a total of 18 unique experiments were conducted to evaluate Anthropomorphic Test Devices (ATD) responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and activation of emergency locator transmitters and crash sensors. Combinations of Hybrid II, Hybrid III, and ES-2 ATDs were placed in forward and side facing seats and occupant results were compared against injury criteria. The structural response of the airframe was assessed based on accelerometers located throughout the airframe and using three-dimensional photogrammetric techniques. Analysis of the photogrammetric data indicated regions of maximum deflection and permanent deformation. The response of TRACT 2 was noticeably different in the horizontal direction due to changes in the cabin configuration and soil surface, with higher acceleration and damage occurring in the cabin. Loads from ATDs in energy absorbing seats and restraints were within injury limits. Severe injury was likely for ATDs in forward facing passenger seats.

AP calculus AB & BC crash course

CERN Document Server

Rosebush, J

2012-01-01

AP Calculus AB & BC Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Calculus AB & BC Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Calculus AB & BC course description outline and actual AP test questions. It covers only the information tested on the exams, so you can make the most of your valuable study time. Written by experienced math teachers, our

Antilock braking system effectiveness in prevention of road traffic crashes in Iran.

Science.gov (United States)

Khorasani-Zavareh, Davoud; Shoar, Saeed; Saadat, Soheil

2013-05-04

Anti-lock Brake System (ABS) helps the equipped vehicles to stop under heavy braking, in a shorter distance and with a better control of direction. It was expected that this technology will reduce the rate of fatal road traffic crashes (RTC); however, the outcome is controversial in the real world. The aim of this study is to compare the claimed annual incidence rate and financial losses due to RTCs in ABS vs. non-ABS personal vehicles in Iran. A telephone survey among drivers of two similar models of personal vehicles was arranged. The studied vehicles were of the same brand and type; but only one of them was equipped with ABS. The number of RTCs, subsequent financial loss, and drivers' knowledge and perception about ABS were sought. The sample consisted of drivers of 1232 ABS and 3123 non-ABS vehicles. The annual incidence rate of RTC involving another vehicle was 145.1 (134.8-155.9) per 1000 vehicle-years and there was not a statistically significant difference between study groups.The incidence of RTC with another vehicle due to brake failure was 50.3 (42.9-58.5) for 1000 non ABS vehicle-years and 30.0 (21.2-41.2) for 1000 ABS equipped vehicle-years. The difference was statistically significant after adjustment for the driver and vehicle's age and the daily driving time. The attributable risk of RTC for non-ABS vehicles was 20/1000 vehicles and the excess fraction was 39.8%. The mean financial loss due to reported RTCs was $987.9 ± $1547.3 US Dollars and there was not a statistically significant difference between study groups. While 61.1% of ABS vehicle drivers reported situations in which they believed the ABS had prevented a crash, 44.1% of them however, they did not know how to use ABS efficiently. Law enforcement to maintain safe distance and adhere to speed limit while driving, is needed to raise the effectiveness of ABS. This is as necessary as considering mandatory outfitting of ABS. Safety authorities should first consider the global experience

Mitigating Wind Induced Truck Crashes

Science.gov (United States)

2009-12-25

Dangerous weather and high wind in particular, is a common contributing factor in truck crashes. High wind speeds have been documented as a perennial cause of truck crashes in Kansas and other Great Plains states. The possibility of reducing such cra...

Influences of pre-crash braking induced dummy - forward displacements on dummy behaviour during EuroNCAP frontal crashtest.

Science.gov (United States)

Woitsch, Gernot; Sinz, Wolfgang

2014-01-01

Combination of active and passive safety systems is a future key to further improvement in vehicle safety. Autonomous braking systems are able to reduce collision speeds, and therefore severity levels significantly. Passengers change their position due to pre-impact vehicle motion, a fact, which has not yet been considered in common crash tests. For this paper, finite elements simulations of crash tests were performed to show that forward displacements due to pre-crash braking do not necessarily increase dummy load levels. So the influence of different pre-crash scenarios, all leading to equal closing speeds in the crash phase, are considered in terms of vehicle motion (pitching, deceleration) and restraint system configurations (belt load limiter, pretensioner). The influence is evaluated by dummy loads as well as contact risk between the dummy and the interior. Copyright © 2013 Elsevier Ltd. All rights reserved.

Advances in Crash Response

Centers for Disease Control (CDC) Podcasts

2009-06-29

In this podcast, Dr. Richard C. Hunt, Director of CDC's Division of Injury Response, provides an overview on the benefits of using an Advanced Automatic Collision Notification system, or AACN, to help with emergency triage of people injured in vehicle crashes.  Created: 6/29/2009 by National Center for Injury Prevention and Control (NCIPC), Division of Injury Response (DIR).   Date Released: 6/29/2009.

Analyzing Traffic Crash Severity in Work Zones under Different Light Conditions

Directory of Open Access Journals (Sweden)

Xinxin Wei

2017-01-01

Full Text Available Previous studies have investigated various factors that contribute to the severity of work zone crashes. However, little has been done on the specific effects of light conditions. Using the data from the Enhanced Tennessee Roadway Information Management System (E-TRIMS, crashes that occurred in the Tennessee work zones during 2003–2015 are categorized into three light conditions: daylight, dark-lighted, and dark-not-lighted. One commonly used decision tree method—Classification and Regression Trees (CART—is adopted to investigate the factors contributing to crash severity in highway work zones under these light conditions. The outcomes from the three decision trees with differing light conditions show significant differences in the ranking and importance of the factors considered in the study, thereby indicating the necessity of examining traffic crashes according to light conditions. By separately considering the crash characteristics under different light conditions, some new findings are obtained from this study. The study shows that an increase in the number of lanes increases the crash severity level in work zones during the day while decreasing the severity at night. Similarly, drugs and alcohol are found to increase the severity level significantly under the dark-not-lighted condition, while they have a limited influence under daylight and dark-lighted conditions.

Investigation of Influential Factors for Bicycle Crashes Using a Spatiotemporal Model

Science.gov (United States)

Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.

2017-09-01

Despite the numerous potential advantages of indulging in bicycling, such as elevation of health and environment along with mitigation of congestion, the cyclists are a vulnerable group of commuters which is exposed to safety risks. This study aims to investigate the explanatory variables at transportation planning level which have a significant impact on the bicycle crashes. To account for the serial changes around the built environment, the linear time trend as well as time-varying coefficients are utilized for the covariates. These model modifications help account for the variations in the environment which may escape the incorporated variables due to lack of robustness in data. Also, to incorporate the interaction of roadway, demographic, and socioeconomic features within a Traffic Analysis Zone (TAZ), with the bicycle crashes of that area, a spatial correlation is integrated. This spatial correlation accounts for the spatially structured random effects which capture the unobserved heterogeneity and add towards building more comprehensive model with relatively precise estimates. Two different age groups, the student population in the TAZs, the presence of arterial roads and bike lanes, were observed to be statistically significant variables related with bicycle crashes. These observations will guide the transportation planning organizations which focus on the entity of TAZ while developing policies. The results of the current study establish a quantifies relationship between the significant factors and the crash count which will enable the planners to choose the most cost-efficient, yet most productive, factors which needs to be addressed for mitigation of crashes.

Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes.

Science.gov (United States)

Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu

Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with remaining cases in relation to crash and vehicular characteristics. TAI cases of later crash year (CY) (2004-2012) were compared to those in earlier CY (1996-2003) in relation to TAI severity (minor, moderate, severe and non-survivable). TAI cases in newer model year (MY) vehicles (1999-2012) were compared to those in older vehicles (1988-98) in relation to injury source (steering wheel, front, left, seat belt, air bag and other or unknown). Analysis was stratified by direction of impact (frontal and near-side) and the use of restraints. The similar TAI severity of earlier and later CY among frontal crashes suggests that the observed changes in the adjusted odds of injury seen in NASS-CDS are not due to an increase in injury detection. The decrease in TAI severity among newer vehicles in near-side crashes of later CY is consistent with a beneficial effect of crashworthiness improvements for this crash configuration. A shift of injury source in frontal crashes from the steering wheel in older vehicles to "front of vehicle structures", "seat belts" and "unknown and other" in newer vehicles should suggest potential sites for crashworthiness improvements.

Under-reporting of road traffic crash data in Ghana.

Science.gov (United States)

Salifu, Mohammed; Ackaah, Williams

2012-01-01

Having reliable estimates of the shortfalls in road traffic crash data is an important prerequisite for setting more realistic targets for crash/casualty reduction programmes and for a better appreciation of the socio-economic significance of road traffic crashes. This study was carried out to establish realistic estimates of the overall shortfall (under-reporting) in the official crash statistics in Ghana over an eight-year period (1997-2004). Surveys were conducted at hospitals and among drivers to generate relevant alternative data which were then matched against records in police crash data files and the official database. Overall shortfalls came from two sources, namely, 'non-reporting' and 'under-recording'. The results show that the level of non-reporting varied significantly with the severity of the crash from about 57% for property damage crashes through 8% for serious injury crashes to 0% for fatal crashes. Crashes involving cyclists and motorcyclists were also substantially non-reported. Under-recording on the other hand declined significantly over the period from an average of 37% in 1997-1998 to 27% in 2003-2004. Thus, the official statistics of road traffic crashes in Ghana are subject to significant shortfalls that need to be accounted for. Correction factors have therefore been suggested for adjusting the official data.

How similar are two-unit bicycle and motorcycle crashes?

Science.gov (United States)

Haworth, Narelle; Debnath, Ashim Kumar

2013-09-01

This paper explores the similarities and differences between bicycle and motorcycle crashes with other motor vehicles. If similar treatments can be effective for both bicycle and motorcycle crashes, then greater benefits in terms of crash costs saved may be possible for the same investment in treatments. To reduce the biases associated with under-reporting of these crashes to police, property damage and minor injury crashes were excluded. The most common crash type for both bicycles (31.1%) and motorcycles (24.5%) was intersection from adjacent approaches. Drivers of other vehicles were coded most at fault in the majority of two-unit bicycle (57.0%) and motorcycle crashes (62.7%). The crash types, patterns of fault and factors affecting fault were generally similar for bicycle and motorcycle crashes. This confirms the need to combat the factors contributing to failure of other drivers to yield right of way to two-wheelers, and suggest that some of these actions should prove beneficial to the safety of both motorized and non-motorized two-wheelers. In contrast, child bicyclists were more often at fault, particularly in crashes involving a vehicle leaving the driveway or footpath. The greater reporting of violations by riders and drivers in motorcycle crashes also deserves further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characteristics of Single Vehicle Crashes with a Teen Driver in South Carolina, 2005-2008.

Science.gov (United States)

Shults, Ruth A; Bergen, Gwen; Smith, Tracy J; Cook, Larry; Kindelberger, John; West, Bethany

2017-09-22

Teens' crash risk is highest in the first years of independent driving. Circumstances surrounding fatal crashes have been widely documented, but less is known about factors related to nonfatal teen driver crashes. This study describes single vehicle nonfatal crashes involving the youngest teen drivers (15-17 years), compares these crashes to single vehicle nonfatal crashes among adult drivers (35-44 years) and examines factors related to nonfatal injury producing crashes for teen drivers. Police crash data linked to hospital inpatient and emergency department data for 2005-2008 from the South Carolina Crash Outcomes Data Evaluation System (CODES) were analyzed. Nonfatal, single vehicle crashes involving passenger vehicles occurring on public roadways for teen (15-17 years) drivers were compared with those for adult (35-44 years) drivers on temporal patterns and crash risk factors per licensed driver and per vehicle miles traveled. Vehicle miles traveled by age group was estimated using data from the 2009 National Household Travel Survey. Multivariable log-linear regression analysis was conducted for teen driver crashes to determine which characteristics were related to crashes resulting in a minor/moderate injury or serious injury to at least one vehicle occupant. Compared with adult drivers, teen drivers in South Carolina had 2.5 times the single vehicle nonfatal crash rate per licensed driver and 11 times the rate per vehicle mile traveled. Teen drivers were nearly twice as likely to be speeding at the time of the crash compared with adult drivers. Teen driver crashes per licensed driver were highest during the afternoon hours of 3:00-5:59 pm and crashes per mile driven were highest during the nighttime hours of 9:00-11:59 pm. In 66% of the teen driver crashes, the driver was the only occupant. Crashes were twice as likely to result in serious injury when teen passengers were present than when the teen driver was alone. When teen drivers crashed while

Analysis of near crashes among teen, young adult, and experienced adult drivers using the SHRP2 naturalistic driving study.

Science.gov (United States)

Seacrist, Thomas; Douglas, Ethan C; Huang, Elaine; Megariotis, James; Prabahar, Abhiti; Kashem, Abyaad; Elzarka, Ayya; Haber, Leora; MacKinney, Taryn; Loeb, Helen

2018-02-28

Motor vehicle crashes are the leading cause of death among young drivers. Though previous research has focused on crash events, near crashes offer additional data to help identify driver errors that could potentially lead to crashes as well as evasive maneuvers used to avoid them. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study (NDS) contains extensive data on real-world driving and offers a reliable methodology to quantify and study near crashes. This article presents findings on near crashes and how they compare to crash events among teen, young adult, and experienced adult drivers. A subset from the SHRP2 database consisting of 1,653 near crashes for teen (16-19 years, n = 550), young adult (20-24 years, n = 748), and experienced adult (35-54 years, n = 591) drivers was used. Onboard instrumentation including scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to classify near crashes based on 7 types: rear-end, road departure, intersection, head-on, side-swipe, pedestrian/cyclist, and animal. Near crash rates, incident type, secondary tasks, and evasive maneuvers were compared across age groups and between crashes and near crashes. For rear-end near crashes, vehicle dynamic variables including near crash severity, headway distance, time headway, and time to collision at the time of braking were compared across age groups. Crashes and near crashes were combined to compare the frequency of critical events across age. Teen drivers exhibited a significantly higher (P systems based on the most common driving errors for vulnerable road users.

Prescription medicines and the risk of road traffic crashes: a French registry-based study.

Directory of Open Access Journals (Sweden)

Ludivine Orriols

2010-11-01

Full Text Available In recent decades, increased attention has been focused on the impact of disabilities and medicinal drug use on road safety. The aim of our study was to investigate the association between prescription medicines and the risk of road traffic crashes, and estimate the attributable fraction.We extracted and matched data from three French nationwide databases: the national health care insurance database, police reports, and the national police database of injurious crashes. Drivers identified by their national health care number involved in an injurious crash in France, between July 2005 and May 2008, were included in the study. Medicines were grouped according to the four risk levels of the French classification system (from 0 [no risk] to 3 [high risk]. We included 72,685 drivers involved in injurious crashes. Users of level 2 (odds ratio [OR]  = 1.31 [1.24-1.40] and level 3 (OR  = 1.25 [1.12-1.40] prescription medicines were at higher risk of being responsible for a crash. The association remained after adjustment for the presence of a long-term chronic disease. The fraction of road traffic crashes attributable to levels 2 and 3 medications was 3.3% [2.7%-3.9%]. A within-person case-crossover analysis showed that drivers were more likely to be exposed to level 3 medications on the crash day than on a control day, 30 days earlier (OR  = 1.15 [1.05-1.27].The use of prescription medicines is associated with a substantial number of road traffic crashes in France. In light of the results, warning messages appear to be relevant for level 2 and 3 medications and questionable for level 1 medications. A follow-up study is needed to evaluate the impact of the warning labeling system on road traffic crash prevention.

Volvo and Infiniti drivers' experiences with select crash avoidance technologies.

Science.gov (United States)

Braitman, Keli A; McCartt, Anne T; Zuby, David S; Singer, Jeremiah

2010-06-01

Vehicle-based crash avoidance systems can potentially reduce crashes, but success depends on driver acceptance and understanding. This study gauged driver use, experience, and acceptance among early adopters of select technologies. Telephone interviews were conducted in early 2009 with 380 owners of Volvo vehicles equipped with forward collision warning with autobrake, lane departure warning, side-view assist, and/or active bi-xenon headlights and 485 owners of Infiniti vehicles with lane departure warning/prevention. Most owners kept systems turned on most of the time, especially forward collision warning with autobrake and side-view assist. The exception was lane departure prevention; many owners were unaware they had it, and the system must be activated each time the vehicle is started. Most owners reported being safer with the technologies and would want them again on their next vehicles. Perceived false or unnecessary warnings were fairly common, particularly with side-view assist. Some systems were annoying, especially lane departure warning. Many owners reported safer driving behaviors such as greater use of turn signals (lane departure warning), increased following distance (forward collision warning), and checking side mirrors more frequently (side-view assist), but some reported driving faster at night (active headlights). Despite some unnecessary or annoying warnings, most Volvo and Infiniti owners use crash avoidance systems most of the time. Among early adopters, the first requirement of effective warning systems (that owners use the technology) seems largely met. Systems requiring activation by drivers for each trip are used less often. Owner experience with the latest technologies from other automobile manufacturers should be studied, as well as for vehicles on which technologies are standard (versus optional) equipment. The effectiveness of technologies in preventing and mitigating crashes and injuries, and user acceptance of interfaces, should be

Influence of pedestrian age and gender on spatial and temporal distribution of pedestrian crashes.

Science.gov (United States)

Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas

2018-01-02

Every year, about 1.24 million people are killed in traffic crashes worldwide and more than 22% of these deaths are pedestrians. Therefore, pedestrian safety has become a significant traffic safety issue worldwide. In order to develop effective and targeted safety programs, the location- and time-specific influences on vehicle-pedestrian crashes must be assessed. The main purpose of this research is to explore the influence of pedestrian age and gender on the temporal and spatial distribution of vehicle-pedestrian crashes to identify the hotspots and hot times. Data for all vehicle-pedestrian crashes on public roadways in the Melbourne metropolitan area from 2004 to 2013 are used in this research. Spatial autocorrelation is applied in examining the vehicle-pedestrian crashes in geographic information systems (GIS) to identify any dependency between time and location of these crashes. Spider plots and kernel density estimation (KDE) are then used to determine the temporal and spatial patterns of vehicle-pedestrian crashes for different age groups and genders. Temporal analysis shows that pedestrian age has a significant influence on the temporal distribution of vehicle-pedestrian crashes. Furthermore, men and women have different crash patterns. In addition, results of the spatial analysis shows that areas with high risk of vehicle-pedestrian crashes can vary during different times of the day for different age groups and genders. For example, for those between ages 18 and 65, most vehicle-pedestrian crashes occur in the central business district (CBD) during the day, but between 7:00 p.m. and 6:00 a.m., crashes among this age group occur mostly around hotels, clubs, and bars. This research reveals that temporal and spatial distributions of vehicle-pedestrian crashes vary for different pedestrian age groups and genders. Therefore, specific safety measures should be in place during high crash times at different locations for different age groups and genders to

The effects of age, gender, and crash types on drivers' injury-related health care costs.

Science.gov (United States)

Shen, Sijun; Neyens, David M

2015-04-01

There are many studies that evaluate the effects of age, gender, and crash types on crash related injury severity. However, few studies investigate the effects of those crash factors on the crash related health care costs for drivers that are transported to hospital. The purpose of this study is to examine the relationships between drivers' age, gender, and the crash types, as well as other crash characteristics (e.g., not wearing a seatbelt, weather condition, and fatigued driving), on the crash related health care costs. The South Carolina Crash Outcome Data Evaluation System (SC CODES) from 2005 to 2007 was used to construct six separate hierarchical linear regression models based on drivers' age and gender. The results suggest that older drivers have higher health care costs than younger drivers and male drivers tend to have higher health care costs than female drivers in the same age group. Overall, single vehicle crashes had the highest health care costs for all drivers. For males older than 64-years old sideswipe crashes are as costly as single vehicle crashes. In general, not wearing a seatbelt, airbag deployment, and speeding were found to be associated with higher health care costs. Distraction-related crashes are more likely to be associated with lower health care costs in most cases. Furthermore this study highlights the value of considering drivers in subgroups, as some factors have different effects on health care costs in different driver groups. Developing an understanding of longer term outcomes of crashes and their characteristics can lead to improvements in vehicle technology, educational materials, and interventions to reduce crash-related health care costs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Geo-demographic analysis of fatal motorcycle crashes

Science.gov (United States)

2001-01-01

The objective of this study is to analyze the combined motor vehicle crash data from the Fatality Analysis Reporting System (FARS) with the Claritas geo-demographic database from the lifestyle perspective to determine the appropriate media to use in ...

Factors influencing pediatric Injury Severity Score and Glasgow Coma Scale in pediatric automobile crashes: results from the Crash Injury Research Engineering Network.

Science.gov (United States)

Ehrlich, Peter F; Brown, J Kristine; Sochor, Mark R; Wang, Stewart C; Eichelberger, Martin E

2006-11-01

Motor vehicle crashes account for more than 50% of pediatric injuries. Triage of pediatric patients to appropriate centers can be based on the crash/injury characteristics. Pediatric motor vehicle crash/injury characteristics can be determined from an in vitro laboratory using child crash dummies. However, to date, no detailed data with respect to outcomes and crash mechanism have been presented with a pediatric in vivo model. The Crash Injury Research Engineering Network is comprised of 10 level 1 trauma centers. Crashes were examined with regard to age, crash severity (DeltaV), crash direction, restraint use, and airbag deployment. Multiple logistic regression analysis was performed with Injury Severity Score (ISS) and Glasgow Coma Scale (GCS) as outcomes. Standard age groupings (0-4, 5-9, 10-14, and 15-18) were used. The database is biases toward a survivor population with few fatalities. Four hundred sixty-one motor vehicle crashes with 2500 injuries were analyzed (242 boys, 219 girls). Irrespective of age, DeltaV > 30 mph resulted in increased ISS and decreased GCS (eg, for 0-4 years, DeltaV 30: ISS = 19.5, GCS = 10.6; P 15) injuries than did backseat passengers (odds ratio, 1.7; 95% confidence interval, 0.7-3.4). A trend was noted for children younger than 12 years sitting in the front seat to have increased ISS and decreased GCS with airbag deployment but was limited by case number. A reproducible pattern of increased ISS and lower GCS characterized by high severity, lateral crashes in children was noted. Further analysis of the specific injuries as a function and the crash characteristic can help guide management and prevention strategies.

Crash data modeling with a generalized estimator.

Science.gov (United States)

Ye, Zhirui; Xu, Yueru; Lord, Dominique

2018-05-11

The investigation of relationships between traffic crashes and relevant factors is important in traffic safety management. Various methods have been developed for modeling crash data. In real world scenarios, crash data often display the characteristics of over-dispersion. However, on occasions, some crash datasets have exhibited under-dispersion, especially in cases where the data are conditioned upon the mean. The commonly used models (such as the Poisson and the NB regression models) have associated limitations to cope with various degrees of dispersion. In light of this, a generalized event count (GEC) model, which can be generally used to handle over-, equi-, and under-dispersed data, is proposed in this study. This model was first applied to case studies using data from Toronto, characterized by over-dispersion, and then to crash data from railway-highway crossings in Korea, characterized with under-dispersion. The results from the GEC model were compared with those from the Negative binomial and the hyper-Poisson models. The cases studies show that the proposed model provides good performance for crash data characterized with over- and under-dispersion. Moreover, the proposed model simplifies the modeling process and the prediction of crash data. Copyright © 2018 Elsevier Ltd. All rights reserved.

Wrong-way driving crashes on French divided roads.

Science.gov (United States)

Kemel, Emmanuel

2015-02-01

The objective of divided roads is to increase users' safety by posting unidirectional traffic flows. It happens however that drivers proceed in the wrong direction, endangering themselves as well as other users. The crashes caused by wrong-way drivers are generally spotlighted by the media and call for public intervention. This paper proposes a characterization of wrong-way driving crashes occurring on French divided road on the 2008-2012 period. The objective is to identify the factors that delineate between wrong-way driving crashes and other crashes. Building on the national injury road crash database, 266 crashes involving a wrong-way driver were identified. Their characteristics (related to timing, location, vehicle and driver) are compared to those of the 22,120 other crashes that occurred on the same roads over the same period. The comparison relies on descriptive statistics, completed by a logistic regression. Wrong-way driving crashes are rare but severe. They are more likely to occur during night hours and on non-freeway roads than other crashes. Wrong-way drivers are older, more likely to be intoxicated, to be locals, to drive older vehicles, mainly passenger cars without passengers, than other drivers. The differences observed across networks can help prioritizing public intervention. Most of the identified WW-driving factors deal with cognitive impairment. Therefore, the specific countermeasures such as alternative road signs should be designed for and tested on cognitively impaired drivers. Nevertheless, WW-driving factors are also risk factors for other types of crashes (e.g. elderly driving, drunk driving and age of the vehicle). This suggests that, instead of (or in addition to) developing WW-driving specific countermeasures, managing these risk factors would help reducing a larger number of crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Heart rate variability (HRV) and muscular system activity (EMG) in cases of crash threat during simulated driving of a passenger car.

Science.gov (United States)

Zużewicz, Krystyna; Roman-Liu, Danuta; Konarska, Maria; Bartuzi, Paweł; Matusiak, Krzysztof; Korczak, Dariusz; Lozia, Zbigniew; Guzek, Marek

2013-10-01

The aim of the study was to verify whether simultaneous responses from the muscular and circulatory system occur in the driver's body under simulated conditions of a crash threat. The study was carried out in a passenger car driving simulator. The crash was included in the driving test scenario developed in an urban setting. In the group of 22 young male subjects, two physiological signals - ECG and EMG were continuously recorded. The length of the RR interval in the ECG signal was assessed. A HRV analysis was performed in the time and frequency domains for 1-minute record segments at rest (seated position), during undisturbed driving as well as during and several minutes after the crash. For the left and right side muscles: m. trapezius (TR) and m. flexor digitorum superficialis (FDS), the EMG signal amplitude was determined. The percentage of maximal voluntary contraction (MVC) was compared during driving and during the crash. As for the ECG signal, it was found that in most of the drivers changes occurred in the parameter values reflecting HRV in the time domain. Significant changes were noted in the mean length of RR intervals (mRR). As for the EMG signal, the changes in the amplitude concerned the signal recorded from the FDS muscle. The changes in ECG and EMG were simultaneous in half of the cases. Such parameters as mRR (ECG signal) and FDS-L amplitude (EMG signal) were the responses to accident risk. Under simulated conditions, responses from the circulatory and musculoskeletal systems are not always simultaneous. The results indicate that a more complete driver's response to a crash in road traffic is obtained based on parallel recording of two physiological signals (ECG and EMG).

Exploring cycle crash characteristics in Malaysia

Directory of Open Access Journals (Sweden)

Hamzah A.

2017-01-01

Full Text Available This paper explains the cycle road crash trend, characteristics and injuries in Malaysia. It analyses the in-depth road crash investigation data collected by the Royal Malaysian Police which was made available to MIROS crash database. Fatality data was utilized due to its consistency. Cycle casualties reflected a continual downward pattern for year 2009 to 2014 in which the number of cycle crash involvement reduced by 49% and fatalities dropped by 42%. Among the prevalent factors of cycle fatalities are >60 age group, federal and state roads and straight road sections, rural and small towns, evening peak hours, and mainly involving cars and motorcycles. It is hoped that all these information would spark interests to improve cycle safety in Malaysia.

2008 South Dakota motor vehicle traffic crash summary

Science.gov (United States)

2009-06-01

The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2008 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...

2009 South Dakota motor vehicle traffic crash summary

Science.gov (United States)

2010-06-01

The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2009 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...

The Pattern of Road Traffic Crashes in South East Iran.

Science.gov (United States)

Rad, Mahdieh; Martiniuk, Alexandra Lc; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan

2016-09-01

In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future.

A Methodology to Efficiently Compare Operating System Stability

NARCIS (Netherlands)

van der Kouwe, E.; Giuffrida, C.; Ghitulete, R.; Tanenbaum, A.S.

2015-01-01

Despite decades of advances in software engineering, operating systems (OSes) are still plagued by crashes due to software faults, calling for techniques to improve OS stability when faults occur. Evaluating such techniques requires a way to compare the stability of different OSes that is both

2010 South Dakota motor vehicle traffic crash summary

Science.gov (United States)

2011-01-01

The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical Trends and 2010 Motor Vehicle Traffic Crash Profile. The Historical Trend section provides information on alcohol involvement in motor vehicle crashes, severity of ...

Large truck and bus crash facts, 2008. 

Science.gov (United States)

2010-03-01

This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2008. Selected crash statistics on passenger : vehicles are also presen...

Using medico-legal data to investigate fatal older road user crash circumstances and risk factors.

Science.gov (United States)

Koppel, Sjaan; Bugeja, Lyndal; Smith, Daisy; Lamb, Ashne; Dwyer, Jeremy; Fitzharris, Michael; Newstead, Stuart; D'Elia, Angelo; Charlton, Judith

2018-02-17

This study used medico-legal data to investigate fatal older road user (ORU, aged 65 years and older) crash circumstances and risk factors relating to 4 key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. The Coroners' Court of Victoria's (CCOV) Surveillance Database was searched to identify and describe the frequency and rate per 100,000 population of fatal ORU crashes in the Australian state of Victoria for 2013-2014. Information relating to the deceased ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. One hundred and thirty-eight unintentional fatal ORU crashes were identified in the CCOV Surveillance Database. Of these fatal ORU crashes, most involved older drivers (44%), followed by older pedestrians (32%), older passengers (17%), older pedal cyclists (4%), older motorcyclists (1%), and older mobility scooter users (1%). The average annual rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI], 6.0-10.2). In terms of the crash characteristics and circumstances, most fatal ORU crashes involved a counterpart (98%), of which the majority were passenger cars (50%) or fixed/stationary objects (25%), including trees (46%) or embankments (23%). In addition, most fatal ORU crashes occurred close to home (73%), on-road (87%), on roads that were paved (94%), on roads with light traffic volume (37%), and during low-risk conditions: between 12 p.m. and 6 p.m. (44%), on weekdays (80%), during daylight (75%), and under dry/clear conditions (81%). Road user (RU) error was identified by the police and/or the coroner for the majority of fatal crashes (55%), with a significant proportion of deceased ORUs deemed to have failed to yield (54%) or misjudged (41%). RU error was the most significant factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the

Bicycle Crashes

Data.gov (United States)

Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving bicyclists in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

Pedestrian Crashes

Data.gov (United States)

Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving pedestrians in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

A hybrid clustering and classification approach for predicting crash injury severity on rural roads.

Science.gov (United States)

Hasheminejad, Seyed Hessam-Allah; Zahedi, Mohsen; Hasheminejad, Seyed Mohammad Hossein

2018-03-01

As a threat for transportation system, traffic crashes have a wide range of social consequences for governments. Traffic crashes are increasing in developing countries and Iran as a developing country is not immune from this risk. There are several researches in the literature to predict traffic crash severity based on artificial neural networks (ANNs), support vector machines and decision trees. This paper attempts to investigate the crash injury severity of rural roads by using a hybrid clustering and classification approach to compare the performance of classification algorithms before and after applying the clustering. In this paper, a novel rule-based genetic algorithm (GA) is proposed to predict crash injury severity, which is evaluated by performance criteria in comparison with classification algorithms like ANN. The results obtained from analysis of 13,673 crashes (5600 property damage, 778 fatal crashes, 4690 slight injuries and 2605 severe injuries) on rural roads in Tehran Province of Iran during 2011-2013 revealed that the proposed GA method outperforms other classification algorithms based on classification metrics like precision (86%), recall (88%) and accuracy (87%). Moreover, the proposed GA method has the highest level of interpretation, is easy to understand and provides feedback to analysts.

Bubbles, Post-Crash Dynamics, and the Housing Market

OpenAIRE

Crocker H. Liu; Adam Nowak; Stuart Rosenthal

2014-01-01

This paper documents and explains previously unrecognized post-crash dynamics following the collapse of a housing bubble. A simple model predicts that speculative developers ensure stable pre-crash relative prices between small and large homes while their post-crash exit allows small-home relative values to fall. Evidence from Phoenix supports the model. Although home prices doubled 2004-2006, relative prices of small-to-large homes remained nearly constant but then plummeted post-crash. As s...

The effects of roadway characteristics on farm equipment crashes: A GIS approach

Science.gov (United States)

Greenan, Mitchell Joseph

Tractors and other self-propelled farm equipment, such as combines, sprayers, and towed grain carts, are often used on public roadways as the primary means for traveling from homestead to homestead or from homestead to a distributer. Increased roadway exposure has led to a growing concern for crashes involving farm equipment on the public roadway. A handful of studies exist examining public roadway crashes involving farm equipment using crash data, but none thus far have evaluated road segment data to identify road-specific risk factors. The objective of this study is to identify if roadway characteristics (traffic density, speed limit, road type, surface type, road width, and shoulder width) affect the risk of a crash involving farm equipment on Iowa public roadways. A retrospective cohort study of Iowa roads was conducted to identify the types of roads that are at an increased risk of having a farm-equipment crash on them. Crash data from the Iowa Department of Transportation (to identify crashes) were spatial linked to Iowa roadway data using Geographic Information Systems (GIS). Logistic regression was used to calculate ORs and 95% CL. Out of 319,705 road segments in Iowa, 0.4% segments (n=1,337) had a farm equipment crash from 2005-2011. The odds of having a farm equipment crash were significantly higher for road segments with increased traffic density and speed limit. Roads with an average daily traffic volume of at least 1,251 vehicles were at a 5.53 times greater odds of having a crash than roads with a daily traffic volume between 0-30 vehicles. (CI: 3.90-7.83). Roads with a posted speed limit between 50mph and 60mph were at a 4.88 times greater odds of having a crash than roads with a posted speed limit of 30mph or less. (CI: 3.85-6.20). Specific roadway characteristics such as roadway and shoulder width were also associated with the risk of a crash. For every 5 foot increase in road width, the odds for a crash decreased by 6 percent (CI: 0.89-0.99) and

Tracking progress in teenage driver crash risk in the United States since the advent of graduated driver licensing programs.

Science.gov (United States)

McCartt, Anne T; Teoh, Eric R

2015-06-01

This study examined U.S. teenagers' crash rates since 1996, when the first graduated driver licensing (GDL) program in the United State was implemented. Passenger vehicle driver crash involvement rates for 16-19 and 30-59 (middle-aged) year-olds were examined, using data from the Fatality Analysis Reporting System, National Automotive Sampling System General Estimates System, Census Bureau, and National Household Travel Surveys. Per capita fatal and police-reported crash rates in 2012 were lower for 16year-olds than for middle-aged drivers but older teenagers' rates were higher. Mileage-based fatal and police-reported crash rates in 2008 were higher for teenagers than for middle-aged drivers and higher for 16-17year-olds than for older teenagers. In 1996-2012, teenagers' per capita fatal and police-reported crash rates declined sharply, especially for 16-17year-olds, and more so than for middle-aged drivers. Substantial declines also occurred in teenagers' mileage-based fatal and police-reported crash rates from 1995-96 to 2008, generally more so than for middle-aged drivers. Regarding factors in fatal crashes in 1996 and 2012, proportions of young teenagers' crashes occurring at night and with multiple teenage passengers declined, more so than among older teenagers and middle-aged drivers. The proportion of fatally injured drivers who had been drinking declined for teenagers but changed little for middle-aged drivers. Improvements were not apparent in rates of driver errors or speeding among teenage drivers in fatal crashes. Teenage drivers' crash risk dropped during the period of implementation of GDL laws, especially fatal crash types targeted by GDL. However, teenagers' crash risk remains high, and important crash factors remain unaddressed by GDL. Although this study was not designed to examine the role of GDL, the results are consistent with the increased presence of such laws. More gains are achievable if states strengthen their laws. Copyright © 2015

Advances in crash dynamics for aircraft safety

Science.gov (United States)

Guida, M.; Marulo, F.; Abrate, S.

2018-04-01

This paper studies the ability of the fuselage's lower lobe to absorb the energy during a crash landing, where the introduction of the composite materials can improve the crash survivability thanks to the crushing capability of structural parts to limit the effects of deceleration on the occupants. Providing a protective shell around the occupants and minimizing the risks of injuries during and immediately after the crash in the post-crash regime is a safety requirement. This study consists of: (1) numerical and experimental investigations on small components to verify design concepts using high performance composite materials; (2) analyses of full scale crashes of fuselage lower lobes. This paper outlines an approach for demonstrating the crashworthiness characteristics of the airframe performing a drop test at low velocity impact to validate a numerical model obtained by assembling structural components and materials' properties previously obtained by testing coupons and sub-elements.

Nonconformities in real-world fatal crashes--electronic stability control and seat belt reminders.

Science.gov (United States)

Lie, Anders

2012-01-01

Many new safety systems are entering the market. Vision Zero is a safety strategy aiming at the elimination of fatalities and impairing injuries by the use of a holistic model for safe traffic to develop a safe system. The aim of this article is to analyze fatalities in modern cars with respect to the Vision Zero model with special respect to electronic stability control (ESC) systems and modern seat belt reminders (SBRs). The model is used to identify and understand cases where cars with ESC systems lost control and where occupants were unbelted in a seat with seat belt reminders under normal driving conditions. The model for safe traffic was used to analyze in-depth studies of fatal crashes with respect to seat belt use and loss of control. Vehicles from 2003 and later in crashes from January 2004 to mid-2010 were analyzed. The data were analyzed case by case. Cars that were equipped with ESC systems and lost control and occupants not using the seat belt in a seat with a seat belt reminder were considered as nonconformities. A total of 138 fatal crashes involving 152 fatally injured occupants were analyzed. Cars with ESC systems had fewer loss-of-control-relevant cases than cars without ESC systems. Thirteen percent of the ESC-equipped vehicles had loss-of-control-relevant crashes and 36 percent of the cars without ESC systems had loss-of-control-relevant crashes. The analysis indicates that only one car of the 9 equipped with ESC that lost control did it on a road surface with relevant friction when driving within the speed restriction of the road. In seats with seat belt reminders that are in accordance with the European New Car Assessment Programme's (Euro NCAP) protocol, 93 percent of the occupants were using a seat belt. In seats without reminders this number was 74 percent. This study shows that ESC systems result in a very significant reduction in fatal crashes, especially under normal driving conditions. Under extreme driving conditions such as speeding

U.S. Civil Air Show Crashes, 1993 to 2013: Burden, Fatal Risk Factors, and Evaluation of a Risk Index for Aviation Crashes.

Science.gov (United States)

Ballard, Sarah-Blythe; Osorio, Victor B

2015-01-01

This study provides new public health data about U.S. civil air shows. Risk factors for fatalities in civil air show crashes were analyzed. The value of the FIA score in predicting fatal outcomes was evaluated. With the use of the FAA's General Aviation and Air Taxi Survey and the National Transportation Safety Board's data, the incidence of civil air show crashes from 1993 to 2013 was calculated. Fatality risk factors for crashes were analyzed by means of regression methods. The FIA index was validated to predict fatal outcomes by using the factors of fire, instrument conditions, and away-from-airport location, and was evaluated through receiver operating characteristic (ROC) curves. The civil air show crash rate was 31 crashes per 1,000 civil air events. Of the 174 civil air show crashes that occurred during the study period, 91 (52%) involved at least one fatality; on average, 1.1 people died per fatal crash. Fatalities were associated with four major risk factors: fire [adjusted odds ratio (AOR) = 7.1, 95% confidence interval (CI) = 2.4 to 20.6, P Civil air show crashes were marked by a high risk of fatal outcomes to pilots in aerobatic performances but rare mass casualties. The FIA score was not a valid measurement of fatal risk in civil air show crashes.

Gasoline prices and traffic crashes in Alabama, 1999-2009.

Science.gov (United States)

Chi, Guangqing; McClure, Timothy E; Brown, David B

2012-09-01

The price of gasoline has been found to be negatively associated with traffic crashes in a limited number of studies. However, most of the studies have focused either on fatal crashes only or on all crashes but measured over a very short time period. In this study, we examine gasoline price effects on all traffic crashes by demographic groups in the state of Alabama from 1999 to 2009. Using negative binomial regression techniques to examine monthly data from 1999 to 2009 in the state of Alabama, we estimate the effects of changes in gasoline price on changes in automobile crashes. We also examine how these effects differ by age group (16-20, 21-25, 26-30, 31-64, and 65+), gender (male and female), and race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic). The results show that gasoline prices have both short-term and long-term effects on reducing total traffic crashes and crashes of each age, gender, and race/ethnicity group (except Hispanic due to data limitations). The short-term and long-term effects are not statistically different for each individual demographic group. Gasoline prices have a stronger effect in reducing crashes involving drivers aged 16 to 20 than crashes involving drivers aged 31 to 64 and 65+ in the short term; the effects, however, are not statistically different across other demographic groups. Although gasoline price increases are not favored, our findings show that gasoline price increases (or decreases) are associated with reductions (or increases) in the incidence of traffic crashes. If gasoline prices had remained at the 1999 level of $1.41 from 1999 to 2009, applying the estimated elasticities would result in a predicted increase in total crashes of 169,492 (or 11.3%) from the actual number of crashes. If decision makers wish to reduce traffic crashes, increasing gasoline taxes is a possible option-however, doing so would increase travel costs and lead to equity concerns. These findings may help to shape transportation

The trend of road traffic crashes at urban signalised intersection

Science.gov (United States)

Farhana Nasarrudin, Nurul; Razelan, Intan Suhana Mohd

2018-04-01

Road traffic crash is one of the main contributing factors for deaths in the world. Intersection is listed as the second road type which road crashes occurred frequently. Hence, the traffic light was installed to minimise the road crashes at intersection. However, the crashes are still occurring and arising. The objective of this study was to exhibit the trend of road crashes at the signalised intersections. The data of road crashes for the past 6 years were analysed using descriptive analysis. The results showed that the road traffic crashes at three- and four-legged signalised intersection recorded the increasing trend. In conclusion, this finding shows that the road traffic crashes for these types of signalised intersection in Malaysia is rising. It is also one the contributors to the increasing number of crashes in Malaysia. This finding will encourage the local authority to conduct awareness programs on the safety at the signalised intersection.

Alcohol-crash problem in Canada, 2007

Science.gov (United States)

2010-03-01

This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

Alcohol-crash problem in Canada, 2006

Science.gov (United States)

2009-01-01

This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

Alcohol-crash problem in Canada, 2008

Science.gov (United States)

2010-12-01

This report examines: data on alcohol in fatally injured drivers and pedestrians; the number and : percent of people who died in alcohol-related crashes; and alcohol involvement in those crashes : in which someone was seriously injured but not killed...

Feedback control of occupant motion during a crash

NARCIS (Netherlands)

Hesseling, R.J.; Steinbuch, M.; Veldpaus, F.E.; Klisch, T.

2006-01-01

Passive in-vehicle safety systems such as the air bag and the belt restrain the occupant during a crash. However, often their behavior is not optimal in terms of occupant injuries. This paper discusses an approach to design an ideal restraint system. The problem is formulated as a feedback tracking

Multinational Corporations and Stock Price Crash Risk

Directory of Open Access Journals (Sweden)

Anthony May

2016-10-01

Full Text Available A nascent literature in finance and accounting on tail risk in individual stock returns concludes that bad news hoarding by corporate managers engenders sudden, extreme crashes in a firm’s stock price when the bad news is eventually made public. This literature finds that firm-specific crash risk is higher among firms with more severe asymmetric information and agency problems. A hitherto disjointed literature spanning the fields of international business, finance, and accounting suggests that geographic dispersion in a firm’s operations, and especially dispersion across different countries, gives rise to organizational complexities and greater costs of monitoring that can exacerbate asymmetric information and agency problems. Motivated by the confluence of arguments and findings from these two strands of literature, this paper examines whether stock price crash risk is higher among multinational firms than domestic firms. Using a large sample of U.S. headquartered firms during 1987-2011, we find robust evidence that multinational firms are significantly more likely to crash than domestic firms. Moreover, we show that the difference in crash risk between multinational and domestic firms is most acute among firms with weaker corporate governance mechanisms, including weaker shareholder rights, less independent boards, and less stable institutional ownership. Our analysis indicates that stronger monitoring from each of these three governance mechanisms significantly attenuates the positive relation between crash risk and multinationality. Our findings are robust to the use of alternative measures of crash risk and to controlling for known determinants of crash risk identified in prior studies. Our study offers new insights that should hold value for scholars and market participants interested in understanding the implications of heighted agency problems that multinational firms are likely to encounter and scholars and market participants

LS-DYNA Analysis of a Full-Scale Helicopter Crash Test

Science.gov (United States)

Annett, Martin S.

2010-01-01

A full-scale crash test of an MD-500 helicopter was conducted in December 2009 at NASA Langley's Landing and Impact Research facility (LandIR). The MD-500 helicopter was fitted with a composite honeycomb Deployable Energy Absorber (DEA) and tested under vertical and horizontal impact velocities of 26 ft/sec and 40 ft/sec, respectively. The objectives of the test were to evaluate the performance of the DEA concept under realistic crash conditions and to generate test data for validation of a system integrated LS-DYNA finite element model. In preparation for the full-scale crash test, a series of sub-scale and MD-500 mass simulator tests was conducted to evaluate the impact performances of various components, including a new crush tube and the DEA blocks. Parameters defined within the system integrated finite element model were determined from these tests. The objective of this paper is to summarize the finite element models developed and analyses performed, beginning with pre-test and continuing through post test validation.

Resisting "Crash Diet" Staff Development

Science.gov (United States)

Dana, Nancy Fichtman; Yendol-Hoppey, Diane

2008-01-01

People often respond to the pressure of attending a high school reunion or their child's wedding by going on a crash diet to get quick results. In response, friends may marvel about how good they look on the outside. But what folks don't acknowledge is that, in the name of getting results, crash dieters have done some very unhealthy things to…

School start times and teenage driver motor vehicle crashes.

Science.gov (United States)

Foss, Robert D; Smith, Richard L; O'Brien, Natalie P

2018-04-26

Shifting school start times to 8:30 am or later has been found to improve academic performance and reduce behavior problems. Limited research suggests this may also reduce adolescent driver motor vehicle crashes. A change in the school start time from 7:30 am to 8:45 am for all public high schools in one North Carolina county presented the opportunity to address this question with greater methodologic rigor. We conducted ARIMA interrupted time-series analyses to examine motor vehicle crash rates of high school age drivers in the intervention county and 3 similar comparison counties with comparable urban-rural population distribution. To focus on crashes most likely to be affected, we limited analysis to crashes involving 16- & 17-year-old drivers occurring on days when school was in session. In the intervention county, there was a 14% downward shift in the time-series following the 75 min delay in school start times (p = .076). There was no change approaching statistical significance in any of the other three counties. Further analysis indicated marked, statistically significant shifts in hourly crash rates in the intervention county, reflecting effects of the change in school start time on young driver exposure. Crashes from 7 to 7:59 am decreased sharply (-25%, p = .008), but increased similarly from 8 to 8:59 am (21%, p = .004). Crashes from 2 to 2:59 pm declined dramatically (-48%, p = .000), then increased to a lesser degree from 3 to 3:59 pm (32%, p = .024) and non-significantly from 4 to 4:59 (19%, p = .102). There was no meaningful change in early morning or nighttime crashes, when drowsiness-induced crashes might have been expected to be most common. The small decrease in crashes among high school age drivers following the shift in school start time is consistent with the findings of other studies of teen driver crashes and school start times. All these studies, including the present one, have limitations, but the similar

National Motor Vehicle Crash Causation Survey (NMVCCS)

Data.gov (United States)

Department of Transportation — The National Motor Vehicle Crash Causation Survey (NMVVCS) was a nationwide survey of crashes involving light passenger vehicles, with a focus on the factors related...

Gasoline Prices and Their Relationship to Drunk-Driving Crashes

OpenAIRE

Guangqing Chi; Xuan Zhou; Timothy McClure; Paul Gilbert; Arthur Cosby; Li Zhang; Angela Robertson; David Levinson

2010-01-01

This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by age, gender, and race from 2004Ð2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk- driving crashes among younger...

Calibration of Airframe and Occupant Models for Two Full-Scale Rotorcraft Crash Tests

Science.gov (United States)

Annett, Martin S.; Horta, Lucas G.; Polanco, Michael A.

2012-01-01

Two full-scale crash tests of an MD-500 helicopter were conducted in 2009 and 2010 at NASA Langley's Landing and Impact Research Facility in support of NASA s Subsonic Rotary Wing Crashworthiness Project. The first crash test was conducted to evaluate the performance of an externally mounted composite deployable energy absorber under combined impact conditions. In the second crash test, the energy absorber was removed to establish baseline loads that are regarded as severe but survivable. Accelerations and kinematic data collected from the crash tests were compared to a system integrated finite element model of the test article. Results from 19 accelerometers placed throughout the airframe were compared to finite element model responses. The model developed for the purposes of predicting acceleration responses from the first crash test was inadequate when evaluating more severe conditions seen in the second crash test. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used to calibrate model results for the second full-scale crash test. This combination of heuristic and quantitative methods was used to identify modeling deficiencies, evaluate parameter importance, and propose required model changes. It is shown that the multi-dimensional calibration techniques presented here are particularly effective in identifying model adequacy. Acceleration results for the calibrated model were compared to test results and the original model results. There was a noticeable improvement in the pilot and co-pilot region, a slight improvement in the occupant model response, and an over-stiffening effect in the passenger region. This approach should be adopted early on, in combination with the building-block approaches that are customarily used, for model development and test planning guidance. Complete crash simulations with validated finite element models can be used

Crash-Tech 2001. Conference; Crash-Tech 2001. Tagung

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

Improved active and passive safety of motor vehicles has resulted in a very much improved accident statistics. This conference discussed further optimisations in motor car safety. The harmonisation of test specifications world-wide was gone into, with particular interest in compatibility. Safety specifications resulting from current accident research and new legislation were gone into, and the current state of measuring and technology in crash testing was outlined. [German] Aufgrund der Verbesserungen in der aktiven und passiven Sicherheit von Fahrzeugen weisen die Unfallstatistiken in vielen europaeischen Laendern eine erfreuliche Tendenz auf. Die Tagung wird sich mit den Moeglichkeiten der weiteren Optimierung der Verkehrssicherheit befassen. Die 'Crash-Tech 2001' will sich mit dem Motto 'Sind wir auf dem Weg zum World NCAP?' der Harmonisierung der Testvorschriften unter Einbeziehung der Kompatibilitaet widmen. Dazu werden Anforderungen an die Fahrzeugsicherheit diskutiert, die sich sowohl aus der aktuellen Unfallforschung als auch aus den Vorschriften ergeben. Weiterhin wird der aktuelle Stand der Mess- und Versuchstechnik im Unfallversuch vorgestellt. (orig.)

A comprehensive engineering analysis of motorcycle crashes in Maryland.

Science.gov (United States)

2010-12-01

The goal of this study was to identify recurring or common road characteristics of motorcycle crashes : in Maryland from 1998 to 2007. Motorcycle crash data was obtained from the National Highway : Traffic Safety Administrations Crash Outcome Data...

Glass half-full: On-road glance metrics differentiate crashes from near-crashes in the 100-Car data.

Science.gov (United States)

Seppelt, Bobbie D; Seaman, Sean; Lee, Joonbum; Angell, Linda S; Mehler, Bruce; Reimer, Bryan

2017-10-01

Much of the driver distraction and inattention work to date has focused on concerns over drivers removing their eyes from the forward roadway to perform non-driving-related tasks, and its demonstrable link to safety consequences when these glances are timed at inopportune moments. This extensive literature has established, through the analyses of glance from naturalistic datasets, a clear relationship between eyes-off-road, lead vehicle closing kinematics, and near-crash/crash involvement. This paper looks at the role of driver expectation in influencing drivers' decisions about when and for how long to remove their eyes from the forward roadway in an analysis that consider the combined role of on- and off-road glances. Using glance data collected in the 100-Car Naturalistic Driving Study (NDS), near-crashes were examined separately from crashes to examine how momentary differences in glance allocation over the 25-s prior to a precipitating event can differentiate between these two distinct outcomes. Individual glance metrics of mean single glance duration (MSGD), total glance time (TGT), and glance count for off-road and on-road glance locations were analyzed. Output from the AttenD algorithm (Kircher and Ahlström, 2009) was also analyzed as a hybrid measure; in threading together on- and off-road glances over time, its output produces a pattern of glance behavior meaningful for examining attentional effects. Individual glance metrics calculated at the epoch-level and binned by 10-s units of time across the available epoch lengths revealed that drivers in near-crashes have significantly longer on-road glances, and look less frequently between on- and off- road locations in the moments preceding a precipitating event as compared to crashes. During on-road glances, drivers in near-crashes were found to more frequently sample peripheral regions of the roadway than drivers in crashes. Output from the AttenD algorithm affirmed the cumulative net benefit of longer on

Offsite radiological consequence analysis for the bounding aircraft crash accident

International Nuclear Information System (INIS)

OBERG, B.D.

2003-01-01

The purpose of this calculation note is to quantitatively analyze a bounding aircraft crash accident for comparison to the DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', Appendix A, Evaluation Guideline of 25 rem. The potential of aircraft impacting a facility was evaluated using the approach given in DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities''. The following aircraft crash FR-equencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash FR-equency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash FR-equency is ''extremely unlikely.'' (2) The general aviation crash FR-equency is ''extremely unlikely.'' (3) The helicopter crash FR-equency is ''beyond extremely unlikely.'' (4) For the Hanford Site 200 Areas, other aircraft type, commercial or military, each above ground facility, and any other type of underground facility is ''beyond extremely unlikely.'' As the potential of aircraft crash into the 200 Area tank farms is more FR-equent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required

Analysis of traffic crash data in Kentucky : 2004-2008.

Science.gov (United States)

2009-09-01

The report documents an analysis of traffic crash data in Kentucky for the years of 2004 through 2008. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashe...

Analysis of Driver Evasive Maneuvering Prior to Intersection Crashes Using Event Data Recorders.

Science.gov (United States)

Scanlon, John M; Kusano, Kristofer D; Gabler, Hampton C

2015-01-01

Intersection crashes account for over 4,500 fatalities in the United States each year. Intersection Advanced Driver Assistance Systems (I-ADAS) are emerging vehicle-based active safety systems that have the potential to help drivers safely navigate across intersections and prevent intersection crashes and injuries. The performance of an I-ADAS is expected to be highly dependent upon driver evasive maneuvering prior to an intersection crash. Little has been published, however, on the detailed evasive kinematics followed by drivers prior to real-world intersection crashes. The objective of this study was to characterize the frequency, timing, and kinematics of driver evasive maneuvers prior to intersection crashes. Event data recorders (EDRs) downloaded from vehicles involved in intersection crashes were investigated as part of NASS-CDS years 2001 to 2013. A total of 135 EDRs with precrash vehicle speed and braking application were downloaded to investigate evasive braking. A smaller subset of 59 EDRs that collected vehicle yaw rate was additionally analyzed to investigate evasive steering. Each vehicle was assigned to one of 3 precrash movement classifiers (traveling through the intersection, completely stopped, or rolling stop) based on the vehicle's calculated acceleration and observed velocity profile. To ensure that any significant steering input observed was an attempted evasive maneuver, the analysis excluded vehicles at intersections that were turning, driving on a curved road, or performing a lane change. Braking application at the last EDR-recorded time point was assumed to indicate evasive braking. A vehicle yaw rate greater than 4° per second was assumed to indicate an evasive steering maneuver. Drivers executed crash avoidance maneuvers in four-fifths of intersection crashes. A more detailed analysis of evasive braking frequency by precrash maneuver revealed that drivers performing complete or rolling stops (61.3%) braked less often than drivers

Minor crashes and 'whiplash' in the United States.

Science.gov (United States)

Bartsch, Adam J; Gilbertson, Lars G; Prakash, Vikas; Morr, Douglas R; Wiechel, John F

2008-10-01

In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define 'whiplash' injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4 g (s.d. = 0.5 g), respectively. A total of 113 struck vehicle occupants were diagnosed within five weeks post-crash with 761 ICD-9-CM complaints and 427 AIS injuries (99.5% AIS1) attributed to the crashes. No striking vehicle occupants reported complaints. The main ICD-9-CM diagnoses were 40.6% cervical, 22.5% lumbar/sacral and 10.2% thoracic and the main AIS1 diagnoses were 29.7% cervical, 23.2% lumbar/sacral and 14.3% thoracic. The diagnosis disparity was mainly due to coding for pre-existing degenerative diagnosis in ICD-9-CM. Degenerative spine conditions were not significant for increased AIS1 injury risk. Surprisingly, many non-'whiplash' diagnoses were found. The AIS injury diagnosis distribution and frequency in these minor delta-V crashes did not correspond with previous minor rear crash studies. A prospectively collected and unbiased minor rear crash databank in the model of CIREN or NASS is highly desirable to verify or refute these results for the U.S. population since the current study cohort may have been influenced by litigation.

The Effect of Managerial Ability on Future Stock Price Crash Risk: Evidence from Korea

Directory of Open Access Journals (Sweden)

Soo Yeon Park

2017-12-01

Full Text Available This study examines the effect of managerial ability on subsequent stock price crash risk using listed firm data in Korea. Compared to some financially advanced countries, the influence of managers is particularly more powerful in Korea, as ownership and management are not effectively separate in most Korean firms. In addition, we considered the effect of large business groups called Chaebol, which is family-run conglomerates with unique corporate governance system that hugely affect the Korean economy. It is important to recognize determinants of the stock price crash risk which would result in doubt on going concern to enhance the company’s sustainable management. Hence, this study focuses on the managerial ability as one of the main factors of the stock price crash risk. We use the measures of firm-specific stock price crash risk based on Hutton et al. (2009. Managerial ability is estimated through a Data Envelopment Analysis (DEA and tobit regressions following Demerjian et al. (2012. From the empirical tests, there is a negative association between managerial ability and stock price crash risk. This suggests that managers with a higher ability release more voluntary disclosure to signal their ability, ultimately lowering the subsequent stock price crash risk. We also find that firms in large business groups, Chaebol, weaken the negative association between managerial ability and subsequent stock price crash risk.

Statewide analysis of bicycle crashes : [project summary].

Science.gov (United States)

2017-06-01

An extensive literature review was conducted to locate existing studies in four areas: (1) risk factors that affect the frequency and severity of bicycle crashes; (2) bicycle crash causes, patterns, and contributing factors; (3) network screening met...

Using linked data to evaluate motor vehicle crashes involving elderly drivers in Connecticut : Crash Outcome Data Evaluation System (CODES) linked data demonstration project

Science.gov (United States)

1999-09-01

A deterministic algorithm was developed which allowed data from Department of Transportation motor vehicle crash records, state mortality registry records, and hospital admission and emergency department records to be linked for analysis of the impac...

Analisis Penyerapan Energi Crash Box Pola Origami pada Pengujian Frontal Impact Posisi Angular Frontal

Directory of Open Access Journals (Sweden)

Redi Bintarto

2017-05-01

Full Text Available In the car, the body structure is designed in such a way so as to transfer and absorb energy. This serves to minimize the result of this accident related to kinetic energy. This needs a system to absorb the kinetic energy maximally, so as a result of a frontal collision events that can be reduced optimally and kinetic energy can be absorbed by a front body structure. Devices used for absorbing kinetic energy in the car is usually called a crash box, which is located between the main structure and bumper. Crash Box generally tubular thin shaped. It has been a lot of research about the crash box. In this study using crash box origami patterns and using methods taguchi orthogonal array L9 (34. AA7003-T7 aluminum material modeled as bilinear isotropic hardening, the loading method is Frontal Impact Frontal Angular Position with impact angles of 5, 15 and 30 degree by using the finite element software simulation methods. The simulation results showed that the crash box in the lowest possible energy absorption were happened at crash box with 5 degree, with 683 153 Joule energy absorbsion. The highest result was happened to crash box number 5 with the results of 3,140.778 Joule. Lowest absorption on impact of 15 degree and 30 degree were happened to crash box number 1 and number 3 with a value of 245 685 Joule and 174 845 Joule, while the highest absorption at mumber 3 with each value 1,708.521 Joule and 1,750.872 Joule.

Factors Contributing to Crashes among Young Drivers

Directory of Open Access Journals (Sweden)

Lyndel J. Bates

2014-08-01

Full Text Available Young drivers are the group of drivers most likely to crash. There are a number of factors that contribute to the high crash risk experienced by these drivers. While some of these factors are intrinsic to the young driver, such as their age, gender or driving skill, others relate to social factors and when and how often they drive. This article reviews the factors that affect the risk of young drivers crashing to enable a fuller understanding of why this risk is so high in order to assist in developing effective countermeasures.

Teen driver crashes : a report to Congress

Science.gov (United States)

2008-07-01

This report summarizes what is known about the teen driver crash problem and reviews the research on the major contributing factors to the high teen crash rate. Dispositional factors, such as immaturity, inexperience, faulty judgment, and a higher pr...

Impact of connected vehicles on mitigating secondary crash risk

Directory of Open Access Journals (Sweden)

Hong Yang

2017-09-01

Full Text Available Reducing the risk of secondary crashes is a key goal for effective traffic incident management. However, only few countermeasures have been established in practices to achieve the goal. This is mainly due to the stochastic nature of both primary and secondary crashes. Given the emerging connected vehicle (CV technologies, it is highly likely that CVs will soon be able to communicate with each other through the ad-hoc wireless vehicular network. Information sharing among vehicles is deemed to change traffic operations and allow motorists for more proactive actions. Motorists who receive safety messages can be motivated to approach queues and incident sites with more caution. As a result of the improved situational awareness, the risk of secondary crashes is expected to be reduced. To examine whether this expectation is achievable or not, this study aims to assess the impact of connectivity on the risk of secondary crashes. A simulation-based modeling framework that enables vehicle-to-vehicle communication module was developed. Since crashes cannot be directly simulated in micro-simulation, the use of surrogate safety measures was proposed to capture vehicular conflicts as a proxy for secondary crash risk upstream of a primary crash site. An experimental study was conducted based on the developed simulation modeling framework. The results show that the use of connected vehicles can be a viable way to reduce the risk of secondary crashes. Their impact is expected to change with an increasing market penetration of connected vehicles.

MOTORCYCLE CRASH PREDICTION MODEL FOR NON-SIGNALIZED INTERSECTIONS

Directory of Open Access Journals (Sweden)

S. HARNEN

2003-01-01

Full Text Available This paper attempts to develop a prediction model for motorcycle crashes at non-signalized intersections on urban roads in Malaysia. The Generalized Linear Modeling approach was used to develop the model. The final model revealed that an increase in motorcycle and non-motorcycle flows entering an intersection is associated with an increase in motorcycle crashes. Non-motorcycle flow on major road had the greatest effect on the probability of motorcycle crashes. Approach speed, lane width, number of lanes, shoulder width and land use were also found to be significant in explaining motorcycle crashes. The model should assist traffic engineers to decide the need for appropriate intersection treatment that specifically designed for non-exclusive motorcycle lane facilities.

CDC Vital Signs: Motor Vehicle Crash Injuries: Costly but Preventable

Science.gov (United States)

... Press Kit Read the MMWR Science Clips Motor Vehicle Crash Injuries Costly but Preventable Language: English (US) ... and how to prevent future crashes. Problem Motor vehicle crashes are a leading cause of injury in ...

Assessing the role of pavement macrotexture in preventing crashes on highways.

Science.gov (United States)

Pulugurtha, Srinivas S; Kusam, Prasanna R; Patel, Kuvleshay J

2010-02-01

The objective of this article is to assess the role of pavement macrotexture in preventing crashes on highways in the State of North Carolina. Laser profilometer data obtained from the North Carolina Department of Transportation (NCDOT) for highways comprising four corridors are processed to calculate pavement macrotexture at 100-m (approximately 330-ft) sections according to the American Society for Testing and Materials (ASTM) standards. Crash data collected over the same lengths of the corridors were integrated with the calculated pavement macrotexture for each section. Scatterplots were generated to assess the role of pavement macrotexture on crashes and logarithm of crashes. Regression analyses were conducted by considering predictor variables such as million vehicle miles of travel (as a function of traffic volume and length), the number of interchanges, the number of at-grade intersections, the number of grade-separated interchanges, and the number of bridges, culverts, and overhead signs along with pavement macrotexture to study the statistical significance of relationship between pavement macrotexture and crashes (both linear and log-linear) when compared to other predictor variables. Scatterplots and regression analysis conducted indicate a more statistically significant relationship between pavement macrotexture and logarithm of crashes than between pavement macrotexture and crashes. The coefficient for pavement macrotexture, in general, is negative, indicating that the number of crashes or logarithm of crashes decreases as it increases. The relation between pavement macrotexture and logarithm of crashes is generally stronger than between most other predictor variables and crashes or logarithm of crashes. Based on results obtained, it can be concluded that maintaining pavement macrotexture greater than or equal to 1.524 mm (0.06 in.) as a threshold limit would possibly reduce crashes and provide safe transportation to road users on highways.

Side Impact Regulatory Trends, Crash Environment and Injury Risk in the USA.

Science.gov (United States)

Prasad, Priya; Dalmotas, Dainius; Chouinard, Aline

2015-11-01

Light duty vehicles in the US are designed to meet and exceed regulatory standards, self-imposed industry agreements and safety rating tests conducted by NHTSA and IIHS. The evolution of side impact regulation in the US from 1973 to 2015 is discussed in the paper along with two key industry agreements in 2003 affecting design of restraint systems and structures for side impact protection. A combination of all the above influences shows that vehicles in the US are being designed to more demanding and comprehensive requirements than in any other region of the world. The crash environment in the US related to side impacts was defined based on data in the nationally representative crash database NASS. Crash environment factors, including the distribution of cars, light trucks and vans (LTV's), and medium-to-heavy vehicles (MHV's) in the fleet, and the frequency of their interactions with one another in side impacts, were considered. Other factors like, crash severity in terms of closing velocity between two vehicles involved in crash, gender and age of involved drivers in two-vehicle and single vehicle crashes, were also examined. Injury risks in side impacts to drivers and passengers were determined in various circumstances such as near-side, far-side, and single vehicle crashes as a function of crash severity, in terms of estimated closing speed or lateral delta-V. Also injury risks in different pairs of striking and struck cars and LTV's, were estimated. A logistic regression model for studying injury risks in two vehicle crashes was developed. The risk factors included in the model include case and striking vehicles, consisting of cars, SUV's, vans, and pickup trucks, delta-V, damage extent, occupant proximity to the impact side, age and gender of the occupant, and belt use. Results show that car occupants make up the vast majority of serious-to-fatally injured occupants. Injury rates of car occupants in two-vehicle collision are highest when the car is struck by a

Counterfactual simulations applied to SHRP2 crashes: The effect of driver behavior models on safety benefit estimations of intelligent safety systems.

Science.gov (United States)

Bärgman, Jonas; Boda, Christian-Nils; Dozza, Marco

2017-05-01

As the development and deployment of in-vehicle intelligent safety systems (ISS) for crash avoidance and mitigation have rapidly increased in the last decades, the need to evaluate their prospective safety benefits before introduction has never been higher. Counterfactual simulations using relevant mathematical models (for vehicle dynamics, sensors, the environment, ISS algorithms, and models of driver behavior) have been identified as having high potential. However, although most of these models are relatively mature, models of driver behavior in the critical seconds before a crash are still relatively immature. There are also large conceptual differences between different driver models. The objective of this paper is, firstly, to demonstrate the importance of the choice of driver model when counterfactual simulations are used to evaluate two ISS: Forward collision warning (FCW), and autonomous emergency braking (AEB). Secondly, the paper demonstrates how counterfactual simulations can be used to perform sensitivity analyses on parameter settings, both for driver behavior and ISS algorithms. Finally, the paper evaluates the effect of the choice of glance distribution in the driver behavior model on the safety benefit estimation. The paper uses pre-crash kinematics and driver behavior from 34 rear-end crashes from the SHRP2 naturalistic driving study for the demonstrations. The results for FCW show a large difference in the percent of avoided crashes between conceptually different models of driver behavior, while differences were small for conceptually similar models. As expected, the choice of model of driver behavior did not affect AEB benefit much. Based on our results, researchers and others who aim to evaluate ISS with the driver in the loop through counterfactual simulations should be sure to make deliberate and well-grounded choices of driver models: the choice of model matters. Copyright © 2017 Elsevier Ltd. All rights reserved.

Life-threatening motor vehicle crashes in bright sunlight

OpenAIRE

Redelmeier, Donald A.; Raza, Sheharyar

2017-01-01

Abstract Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight. This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estim...

EMPLOYMENT OF ATMS TRAFFIC CONTROL DEVICE DATA TO ASSIST IN IDENTIFICATION OF CRASH-PRONE INTERSECTIONS

Directory of Open Access Journals (Sweden)

Kevin P. HWANG

2008-01-01

Full Text Available This paper employs information from the advanced traffic management system (ATMS of Kaohsiung, Taiwan to help differentiate those crash-prone intersections by discriminant analysis. From the 25,604 records of 2005, 1977 crashes that occurred at 119 intersections with traffic exposure data were compiled to calibrate and validate the model. The road attributes of crash records, traffic control devices and movement exposure are the three types of data used as predicting variables. The correct ratios for model calibration and validation range from 78.33% to 67.80%. if traffic movements are removed, the correct ratios become slightly lowered to 76.67% to 66.10%. Research findings reveal that with or without inclusion of exposure data in identifying high crash-prone intersections for an urban environment does not make a significant difference. in addition, layout and traffic control devices could possibly explain about 66.10 ∼ 78.33% of the possibility that an intersection will become a high crash intersection. it suggests that the developed approach could be a countermeasure for budget constraints and difficulties in continuation of exposure data collection, and the information of ATMS could help identify crash-prone urban intersections.

Estimating under-reporting of road crash injuries to police using multiple linked data collections.

Science.gov (United States)

Watson, Angela; Watson, Barry; Vallmuur, Kirsten

2015-10-01

The reliance on police data for the counting of road crash injuries can be problematic, as it is well known that not all road crash injuries are reported to police which under-estimates the overall burden of road crash injuries. The aim of this study was to use multiple linked data sources to estimate the extent of under-reporting of road crash injuries to police in the Australian state of Queensland. Data from the Queensland Road Crash Database (QRCD), the Queensland Hospital Admitted Patients Data Collection (QHAPDC), Emergency Department Information System (EDIS), and the Queensland Injury Surveillance Unit (QISU) for the year 2009 were linked. The completeness of road crash cases reported to police was examined via discordance rates between the police data (QRCD) and the hospital data collections. In addition, the potential bias of this discordance (under-reporting) was assessed based on gender, age, road user group, and regional location. Results showed that the level of under-reporting varied depending on the data set with which the police data was compared. When all hospital data collections are examined together the estimated population of road crash injuries was approximately 28,000, with around two-thirds not linking to any record in the police data. The results also showed that the under-reporting was more likely for motorcyclists, cyclists, males, young people, and injuries occurring in Remote and Inner Regional areas. These results have important implications for road safety research and policy in terms of: prioritising funding and resources; targeting road safety interventions into areas of higher risk; and estimating the burden of road crash injuries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors related to serious injury in post-NCAP European cars involved in frontal crashes.

Science.gov (United States)

Frampton, Richard; Williams, Owen; Thomas, Pete

2004-01-01

ABSTRACT This study examined the relationship between EuroNCAP ratings for body region protection and real world injury risk for 653 belted drivers in frontal crashes. It was also able to comment on further improvements in crash protection for post-EuroNCAP cars. Protection for the head and lower leg appeared good. In terms of life threatening injury, results showed a need to prioritise chest protection, whilst for impairment, protection for the upper leg and ankle/foot should be considered. The EuroNCAP body region scoring system reflects trends in real crash injury risks to all body regions, except for the chest, where there is no clear trend. More generally, further development in the testing regime could usefully concentrate on a restraint system test and the use of smaller dummies seated appropriately, rather than an increase of the test speed.

Building concepts against airplane crash

International Nuclear Information System (INIS)

Henkel, F.O.; Woelfel, H.

1984-01-01

In Germany safety related buildings of nuclear facilities as well as their equipment are to be designed against airplane crash. While the safety of the structure itself can always be guaranteed by structural means, the induced vibrations may cause severe problems for the equipment. Considerable effort was expended in recent years to comprehend the load case airplane crash in a more exact manner and to evaluate reasonable floor response spectra. Besides this analytical effort, investigations are cited to minimize the induced vibrations by new structural concepts. The present paper gives a survey concerning the development of structural concepts, culminating in the double shell structures that are state of the art today. Then the idea of spring supports, as it is known for the aseismic foundation of buildings, is further developed to a new spring concept which reduces the induced vibrations in an optimum way in the load case airplane crash and which additionally isolates earthquake vibrations. (orig.)

Identification and validation of a logistic regression model for predicting serious injuries associated with motor vehicle crashes.

Science.gov (United States)

Kononen, Douglas W; Flannagan, Carol A C; Wang, Stewart C

2011-01-01

A multivariate logistic regression model, based upon National Automotive Sampling System Crashworthiness Data System (NASS-CDS) data for calendar years 1999-2008, was developed to predict the probability that a crash-involved vehicle will contain one or more occupants with serious or incapacitating injuries. These vehicles were defined as containing at least one occupant coded with an Injury Severity Score (ISS) of greater than or equal to 15, in planar, non-rollover crash events involving Model Year 2000 and newer cars, light trucks, and vans. The target injury outcome measure was developed by the Centers for Disease Control and Prevention (CDC)-led National Expert Panel on Field Triage in their recent revision of the Field Triage Decision Scheme (American College of Surgeons, 2006). The parameters to be used for crash injury prediction were subsequently specified by the National Expert Panel. Model input parameters included: crash direction (front, left, right, and rear), change in velocity (delta-V), multiple vs. single impacts, belt use, presence of at least one older occupant (≥ 55 years old), presence of at least one female in the vehicle, and vehicle type (car, pickup truck, van, and sport utility). The model was developed using predictor variables that may be readily available, post-crash, from OnStar-like telematics systems. Model sensitivity and specificity were 40% and 98%, respectively, using a probability cutpoint of 0.20. The area under the receiver operator characteristic (ROC) curve for the final model was 0.84. Delta-V (mph), seat belt use and crash direction were the most important predictors of serious injury. Due to the complexity of factors associated with rollover-related injuries, a separate screening algorithm is needed to model injuries associated with this crash mode. Copyright © 2010 Elsevier Ltd. All rights reserved.

Multi-level Bayesian analyses for single- and multi-vehicle freeway crashes.

Science.gov (United States)

Yu, Rongjie; Abdel-Aty, Mohamed

2013-09-01

This study presents multi-level analyses for single- and multi-vehicle crashes on a mountainous freeway. Data from a 15-mile mountainous freeway section on I-70 were investigated. Both aggregate and disaggregate models for the two crash conditions were developed. Five years of crash data were used in the aggregate investigation, while the disaggregate models utilized one year of crash data along with real-time traffic and weather data. For the aggregate analyses, safety performance functions were developed for the purpose of revealing the contributing factors for each crash type. Two methodologies, a Bayesian bivariate Poisson-lognormal model and a Bayesian hierarchical Poisson model with correlated random effects, were estimated to simultaneously analyze the two crash conditions with consideration of possible correlations. Except for the factors related to geometric characteristics, two exposure parameters (annual average daily traffic and segment length) were included. Two different sets of significant explanatory and exposure variables were identified for the single-vehicle (SV) and multi-vehicle (MV) crashes. It was found that the Bayesian bivariate Poisson-lognormal model is superior to the Bayesian hierarchical Poisson model, the former with a substantially lower DIC and more significant variables. In addition to the aggregate analyses, microscopic real-time crash risk evaluation models were developed for the two crash conditions. Multi-level Bayesian logistic regression models were estimated with the random parameters accounting for seasonal variations, crash-unit-level diversity and segment-level random effects capturing unobserved heterogeneity caused by the geometric characteristics. The model results indicate that the effects of the selected variables on crash occurrence vary across seasons and crash units; and that geometric characteristic variables contribute to the segment variations: the more unobserved heterogeneity have been accounted, the better

Effect of various pre-crash braking strategies on simulated human kinematic response with varying levels of driver attention

NARCIS (Netherlands)

Rooij, L. van

2011-01-01

In this study, human kinematic response resulting from various pre-crash braking scenarios is quantified. The underlying question is what kind of effect do pre-crash braking systems have on the driver or the front seat passenger.

Minor Crashes and ‘Whiplash’ in the United States

Science.gov (United States)

Bartsch, Adam J.; Gilbertson, Lars G.; Prakash, Vikas; Morr, Douglas R.; Wiechel, John F.

2008-01-01

In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define ‘whiplash’ injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4g (s.d. = 0.5g), respectively. A total of 113 struck vehicle occupants were diagnosed within five weeks post-crash with 761 ICD-9-CM complaints and 427 AIS injuries (99.5% AIS1) attributed to the crashes. No striking vehicle occupants reported complaints. The main ICD-9-CM diagnoses were 40.6% cervical, 22.5% lumbar/sacral and 10.2% thoracic and the main AIS1 diagnoses were 29.7% cervical, 23.2% lumbar/sacral and 14.3% thoracic. The diagnosis disparity was mainly due to coding for pre-existing degenerative diagnosis in ICD-9-CM. Degenerative spine conditions were not significant for increased AIS1 injury risk. Surprisingly, many non-‘whiplash’ diagnoses were found. The AIS injury diagnosis distribution and frequency in these minor delta-V crashes did not correspond with previous minor rear crash studies. A prospectively collected and unbiased minor rear crash databank in the model of CIREN or NASS is highly desirable to verify or refute these results for the U.S. population since the current study cohort may have been influenced by litigation. PMID:19026229

Cell phone use while driving and attributable crash risk.

Science.gov (United States)

Farmer, Charles M; Braitman, Keli A; Lund, Adrian K

2010-10-01

Prior research has estimated that crash risk is 4 times higher when talking on a cell phone versus not talking. The objectives of this study were to estimate the extent to which drivers talk on cell phones while driving and to compute the implied annual number of crashes that could have been avoided if driver cell phone use were restricted. A national survey of approximately 1200 U.S. drivers was conducted. Respondents were asked to approximate the amount of time spent driving during a given day, number of cell phone calls made or received, and amount of driving time spent talking on a cell phone. Population attributable risk (PAR) was computed for each combination of driver gender, driver age, day of week, and time of day. These were multiplied by the corresponding crash counts to estimate the number of crashes that could have been avoided. On average, drivers were talking on cell phones approximately 7 percent of the time while driving. Rates were higher on weekdays (8%), in the afternoon and evening (8%), and for drivers younger than 30 (16%). Based on these use rates, restricting cell phones while driving could have prevented an estimated 22 percent (i.e., 1.3 million) of the crashes in 2008. Although increased rates of cell phone use while driving should be leading to increased crash rates, crash rates have been declining. Reasons for this paradox are unclear. One possibility is that the increase in cell phone use and crash risk due to cell phone use have been overestimated. Another possibility is that cell phone use has supplanted other driving distractions that were similarly hazardous.

Volvo drivers' experiences with advanced crash avoidance and related technologies.

Science.gov (United States)

Eichelberger, Angela H; McCartt, Anne T

2014-01-01

Crash avoidance technologies can potentially prevent or mitigate many crashes, but their success depends in part on driver acceptance. Owners of 2010-2012 model Volvo vehicles with several technologies were interviewed about their experiences. Interviews were conducted in summer 2012 with 155 owners of vehicles with City Safety as a standard feature; 145 owners with an optional technology package that included adaptive cruise control, distance alert, collision warning with full auto brake (and pedestrian detection on certain models), driver alert control, and lane departure warning; and 172 owners with both City Safety and the technology package. The survey response rates were 21 percent for owners with City Safety, 30 percent for owners with the technology package, and 27 percent for owners with both. Ten percent of owners opted out before the telephone survey began, and 18 percent declined to participate when called. Despite some annoyance, most respondents always leave the systems on, although fewer do so for lane departure warning (59%). For each of the systems, at least 80 percent of respondents with the system would want it on their next vehicle. Many respondents reported safer driving habits with the systems (e.g., following less closely with adaptive cruise control, using turn signals more often with lane departure warning). Fewer respondents reported potentially unsafe behavior, such as allowing the vehicle to brake for them at least some of the time. About one third of respondents experienced autonomous braking when they believed they were at risk of crashing, and about one fifth of respondents thought it had prevented a crash. About one fifth of respondents with the technology package reported that they were confused or misunderstood which safety system had activated in their vehicle. Consistent with the results for early adopters in the previous survey of Volvo and Infiniti owners, the present survey found that driver acceptance of the technologies

Improvement of Aircraft Crash Effective Areas for Koeberg Nuclear Power Plant

International Nuclear Information System (INIS)

Momoti, S.; Dongmo, G.B.; Combrink, Y.

2017-01-01

Probabilistic Safety Assessment (PSA): Tool for determining safe functioning of nuclear power plant to meet regulatory requirements; One of the inputs to the PSA are the frequency and consequences of an aircraft crash. Overview: Frequency of Aircraft Crash; Effective Area of an Aircraft Crashing into Koeberg - Aviation Categories, - Shielding of sensitive target buildings; Impact of refining the Effective AreaFrequency of Aircraft Crash

Syncope and Motor Vehicle Crash Risk

DEFF Research Database (Denmark)

Numé, Anna-Karin; Gislason, Gunnar; Christiansen, Christine Benn

2016-01-01

IMPORTANCE: Syncope may have serious consequences for traffic safety. Current clinical guideline recommendations on driving following syncope are primarily based on expert consensus. OBJECTIVE: To identify whether there is excess risk of motor vehicle crashes among patients with syncope compared...... vehicle crashes throughout the follow-up period. This study suggests that syncope should be considered as one of several factors in a broad assessment of fitness to drive....

Assessing the potential benefits of the motorcycle autonomous emergency braking using detailed crash reconstructions.

Science.gov (United States)

Savino, Giovanni; Giovannini, Federico; Baldanzini, Niccolò; Pierini, Marco; Rizzi, Matteo

2013-01-01

The aim of this study was to assess the feasibility and quantitative potential benefits of a motorcycle autonomous emergency braking (MAEB) system in fatal rear-end crashes. A further aim was to identify possible criticalities of this safety system in the field of powered 2-wheelers (PTWs; e.g., any additional risk introduced by the system itself). Seven relevant cases from the Swedish national in-depth fatal crash database were selected. All crashes involved car-following in which a non-anti-lock braking system (ABS)-equipped motorcycle was the bullet vehicle. Those crashes were reconstructed in a virtual environment with Prescan, simulating the road scenario, the vehicles involved, their precrash trajectories, ABS, and, alternatively, MAEB. The MAEB chosen as reference for the investigation was developed within the European Commission-funded Powered Two-Wheeler Integrated Safety (PISa) project and further detailed in later studies, with the addition of the ABS functionality. The boundary conditions of each simulation varied within a range compatible with the uncertainty of the in-depth data and also included a range of possible rider behaviors including the actual one. The benefits of the MAEB were evaluated by comparing the simulated impact speed in each configuration (no ABS/MAEB, ABS only, MAEB). The MAEB proved to be beneficial in a large number of cases. When applicable, the benefits of the system were in line with the expected values. When not applicable, there was no clear evidence of an increased risk for the rider due to the system. MAEB represents an innovative safety device in the field of PTWs, and the feasibility of such a system was investigated with promising results. Nevertheless, this technology is not mature yet for PTW application. Research in the field of passenger cars does not directly apply to PTWs because the activation logic of a braking system is more challenging on PTWs. The deployment of an autonomous deceleration would affect the

Drug and Alcohol Involvement in Four Types of Fatal Crashes*

Science.gov (United States)

Romano, Eduardo; Voas, Robert B.

2011-01-01

Objective: The aim of this study was to explore the relationship of drunk and drugged driving to the occurrence of fatal crashes associated with speeding, failure to obey/yield, inattention, and seat belt nonuse. Method: We examined data for fatally injured drivers involved in single-vehicle crashes killed in states in which more than 79% of the drivers were tested for drugs other than alcohol and had a known result. Results: About 25% of the drivers tested positive for drugs, a figure almost double that estimated by the 2007 National Roadside Survey. Cannabinoids and stimulants each contributed to about 23% of the drug-positive results (6% among all fatally injured single-vehicle drivers). Stimulants more than cannabinoids were found to be associated with the four types of crashes under study. Some drugs showed a protective effect over the four crash types under study. Significant interactions between drugs and alcohol were observed. Stimulants contributed to the different types of fatal crashes irrespective of the levels of alcohol consumed by the drivers. Conclusions: This study provides further evidence of a link between drug consumption and fatal crashes. It also opens the door to some interesting and sometimes unexpected questions regarding the way drugs contribute to crashes, which we found varies depending on the type of crash considered, the class of drug, and the presence of alcohol. Research is also needed on drugs that could have a protective effect on the occurrence of fatal crashes. These findings could be highly relevant to the design of drug-related traffic laws and programs targeted at curbing drugged driving. PMID:21683038

Definition of run-off-road crash clusters-For safety benefit estimation and driver assistance development.

Science.gov (United States)

Nilsson, Daniel; Lindman, Magdalena; Victor, Trent; Dozza, Marco

2018-04-01

Single-vehicle run-off-road crashes are a major traffic safety concern, as they are associated with a high proportion of fatal outcomes. In addressing run-off-road crashes, the development and evaluation of advanced driver assistance systems requires test scenarios that are representative of the variability found in real-world crashes. We apply hierarchical agglomerative cluster analysis to define similarities in a set of crash data variables, these clusters can then be used as the basis in test scenario development. Out of 13 clusters, nine test scenarios are derived, corresponding to crashes characterised by: drivers drifting off the road in daytime and night-time, high speed departures, high-angle departures on narrow roads, highways, snowy roads, loss-of-control on wet roadways, sharp curves, and high speeds on roads with severe road surface conditions. In addition, each cluster was analysed with respect to crash variables related to the crash cause and reason for the unintended lane departure. The study shows that cluster analysis of representative data provides a statistically based method to identify relevant properties for run-off-road test scenarios. This was done to support development of vehicle-based run-off-road countermeasures and driver behaviour models used in virtual testing. Future studies should use driver behaviour from naturalistic driving data to further define how test-scenarios and behavioural causation mechanisms should be included. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparison of four statistical and machine learning methods for crash severity prediction.

Science.gov (United States)

Iranitalab, Amirfarrokh; Khattak, Aemal

2017-11-01

Crash severity prediction models enable different agencies to predict the severity of a reported crash with unknown severity or the severity of crashes that may be expected to occur sometime in the future. This paper had three main objectives: comparison of the performance of four statistical and machine learning methods including Multinomial Logit (MNL), Nearest Neighbor Classification (NNC), Support Vector Machines (SVM) and Random Forests (RF), in predicting traffic crash severity; developing a crash costs-based approach for comparison of crash severity prediction methods; and investigating the effects of data clustering methods comprising K-means Clustering (KC) and Latent Class Clustering (LCC), on the performance of crash severity prediction models. The 2012-2015 reported crash data from Nebraska, United States was obtained and two-vehicle crashes were extracted as the analysis data. The dataset was split into training/estimation (2012-2014) and validation (2015) subsets. The four prediction methods were trained/estimated using the training/estimation dataset and the correct prediction rates for each crash severity level, overall correct prediction rate and a proposed crash costs-based accuracy measure were obtained for the validation dataset. The correct prediction rates and the proposed approach showed NNC had the best prediction performance in overall and in more severe crashes. RF and SVM had the next two sufficient performances and MNL was the weakest method. Data clustering did not affect the prediction results of SVM, but KC improved the prediction performance of MNL, NNC and RF, while LCC caused improvement in MNL and RF but weakened the performance of NNC. Overall correct prediction rate had almost the exact opposite results compared to the proposed approach, showing that neglecting the crash costs can lead to misjudgment in choosing the right prediction method. Copyright © 2017 Elsevier Ltd. All rights reserved.

SELF-REPORTED DIFFERENCES BETWEEN CRASH-INVOLVED AND NON-CRASH-INVOLVED THREE-WHEELER DRIVERS IN SRI LANKA

Directory of Open Access Journals (Sweden)

A.K. SOMASUNDARASWARAN, Dr.

2006-01-01

Full Text Available Despite being an important mode of transportation in the developing world, little research has been conducted to understand the factors contributing to crashes involving three wheel vehicles. This study surveyed a convenient sample of 505 professional three-wheeler drivers in Sri Lanka to explore the similarities and differences in the demographic and work characteristics between three-wheeler drivers who reported experiencing at least one collision in the past twelve months and those who reported that they were not involved in any collisions. Our study revealed some interesting results that were quite different from those obtained in the studies on professional drivers in developed countries. In particular, both drivers with less than one year and more than five years of driving experience in our study were found to be associated with higher probability of crash involvement. Also, the number of trips per day and the average travel distance per trip were found to be insignificant in delineating between crash-involved and non-crash-involved drivers. Moreover, crash-involved drivers, on average, have significantly fewer working days per week and fewer hours per day, suggesting that the conventional approach used in most developed countries to tackle fatigue among professional drivers do not appear to be suitable for solving the road safety problem involving three-wheeler drivers in a developing country. Also, since the age of most drivers falls in a narrow range, this U-shaped relationship is not likely to be a result of youth and ageing but of inexperience in newer drivers and complacency in more experienced drivers. Lastly, since a relatively large proportion of the drivers had driven without a valid driving license, legislation and enforcement interventions are likely to be less effective than education and engineering countermeasures.

Aftershocks following crash of currency exchange rate: The case of RUB/USD in 2014

Science.gov (United States)

Usmanova, Vasilya; Lysogorskiy, Yury V.; Abe, Sumiyoshi

2018-02-01

The dynamical behavior of the currency exchange rate after its large-scale catastrophe is discussed through a case study of the rate of Russian rubles to US dollars after its crash in 2014. It is shown that, similarly to the case of the stock market crash, the relaxation is characterized by a power law, which is in analogy with the Omori-Utsu law for earthquake aftershocks. The waiting-time distribution is found to also obey a power law. Furthermore, the event-event correlation is discussed, and the aging phenomenon and scaling property are observed. Comments are made on (non-)Markovianity of the aftershock process and on a possible relevance of glassy dynamics to the market system after the crash.

Survivors’ experiences from a train crash

Directory of Open Access Journals (Sweden)

Rebecca Forsberg

2011-11-01

Full Text Available Rarely described are people's lived experiences from severe injury events such as train crashes. The number of train crashes named disasters with ≥10 killed and/or ≥100 nonfatally injured grows globally and the trend shows that more people survive these disasters today than did so in the past. This results in an increased number of survivors needing care. The aim of the study was to explore survivors’ experiences from a train crash. Narrative interviews were performed with 14 passengers 4 years after a train crash event. Qualitative content analysis was used to analyse the interviews. Experiences were captured in three main themes: (1 Living in the mode of existential threat describes how the survivors first lost control, then were thrown into a state of unimaginable chaos as they faced death. (2 Dealing with the unthinkable described how survivors restored control, the central role of others, and the importance of reconstructing the event to move forward in their processing. (3 Having cheated death shows how some became shackled by their history, whereas others overcame the haunting of unforgettable memories. Furthermore, the result shows how all experienced a second chance in life. Experiencing a train crash meant that the passengers experienced severe vulnerability and a threat to life and interdependence turned out to play a crucial role. Focusing on helping other passengers on site was one way to regain the loss of control and kept the chaos at bay. Family, friends, and fellow passengers turned out to be extremely important during the recovery process why such closeness should be promoted and facilitated.

Numerical analyses of an aircraft crash on containment building

Energy Technology Data Exchange (ETDEWEB)

Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk [Kyunghee University, Yongin (Korea, Republic of)

2016-05-15

The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values.

Numerical analyses of an aircraft crash on containment building

International Nuclear Information System (INIS)

Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk

2016-01-01

The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values

Information note about the protection of nuclear facilities against aircraft crashes

International Nuclear Information System (INIS)

2001-01-01

The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

Conscientious personality and young drivers’ crash risk

Science.gov (United States)

Ehsani, Johnathon P.; Li, Kaigang; Simons-Morton, Bruce; Tree-McGrath, Cheyenne Fox; Perlus, Jessamyn; O’Brien, Fearghal; Klauer, Sheila G.

2015-01-01

Introduction Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior and crashes and near-crashes, using naturalistic driving research methods. Method Participants’ driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18 months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants’ KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Results Conscientiousness was marginally negatively associated with CNC (path c = −0.034, p = .09) and both potential mediators KRD (path a = −0.040, p = .09) and secondary task engagement while driving (path a = −0.053, p = .03). KRD, but not secondary task engagement, was found to mediate (path b = 0.376, p = .02) the relationship between conscientiousness and CNC (path c’ = −0.025, p = .20). Conclusions Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, suffered fewer CNC. Practical Applications Part of the variability in crash-risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage

Conscientious personality and young drivers' crash risk.

Science.gov (United States)

Ehsani, Johnathon P; Li, Kaigang; Simons-Morton, Bruce G; Fox Tree-McGrath, Cheyenne; Perlus, Jessamyn G; O'Brien, Fearghal; Klauer, Sheila G

2015-09-01

Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior, and crashes and near-crashes, using naturalistic driving research methods. Participants' driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate, and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants' KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Conscientiousness was marginally negatively associated with CNC (path c=-0.034, p=.09) and both potential mediators KRD (path a=-0.040, p=.09) and secondary task engagement while driving (path a=-0.053, p=.03). KRD, but not secondary task engagement, was found to mediate (path b=0.376, p=.02) the relationship between conscientiousness and CNC (path c'=-0.025, p=.20). Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, and suffered fewer CNC. Part of the variability in crash risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage drivers' personality into account when providing guidance, and establishing norms and

Validation of a method to evaluate future impact of road safety interventions, a comparison between fatal passenger car crashes in Sweden 2000 and 2010.

Science.gov (United States)

Strandroth, Johan

2015-03-01

When targeting a society free from serious and fatal road-traffic injuries, it has been a common practice in many countries and organizations to set up time-limited and quantified targets for the reduction of fatalities and injuries. In setting these targets EU and other organizations have recognized the importance to monitor and predict the development toward the target as well as the efficiency of road safety policies and interventions. This study aims to validate a method to forecast future road safety challenges by applying it to the fatal crashes in Sweden in 2000 and using the method to explain the change in fatalities based on the road safety interventions made until 2010. The estimation of the method is then compared to the true outcome in 2010. The aim of this study was to investigate if a residual of crashes produced by a partial analysis could constitute a sufficient base to describe the characteristics of future crashes. show that out of the 332 car occupants killed in 2000, 197 were estimated to constitute the residual in 2010. Consequently, 135 fatalities from 2000 were estimated by the model to be prevented by 2010. That is a predicted reduction of 41% compared to the reduction in the real outcome of 53%, from 332 in 2000 to 156 in 2010. The method was found able to generate a residual of crashes in 2010 from the crashes in 2000 that had a very similar nature, with regards to crash type, as the true outcome of 2010. It was also found suitable to handle double counting and system effects. However, future research is needed in order to investigate how external factors as well as random and systematic variation should be taken into account in a reliable manner. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mechanism for rapid sawtooth crashes in tokamaks

International Nuclear Information System (INIS)

Aydemir, A.Y.; Hazeltine, R.D.

1986-09-01

The sawtooth oscillations in the soft x-ray signals observed in tokamaks are associated with periodic changes in the central electron temperature, T/sub e/. Typically, a slow phase during which the central temperature slowly rises is followed by a fast drop in T/sub e/, associated with flattening of the central temperature. The time scale of the slow phase is determined by various transport processes such as ohmic heating. The resistive internal kink mode was invoked by Kadomtsev to explain the crash phase of the oscillations. Fast crash times observed in the large tokamaks are studied here, especially the fast crashes observed in JET. These sawtooth oscillations are characterized by the absence of any discrenible precursor oscillations, and a rapid collapse of the central temperature in about 100 microseconds. During the crash phase, the hot core region rapidly moves outward and is replaced by colder plasma. Then, this highly asymmetric state relaxes (in ∼100μsec) to a poloidally symmetric state in which a ring of hot plasma surrounds the colder core plasma, producing a hollow pressure profile

Using linked data to evaluate medical and financial outcomes of motor vehicle crashes in Connecticut : Crash Outcome Data Evaluation System (CODES) linked data demonstration project

Science.gov (United States)

1999-09-01

A deterministic algorithm was developed which allowed data from Department of Transportation motor vehicle crash records, state mortality registry records, and hospital admission and emergency department records to be linked for analysis of the finan...

Three Cases of Spine Fractures after an Airplane Crash.

Science.gov (United States)

Lee, Han Joo; Moon, Bong Ju; Pennant, William A; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum; Ha, Yoon

2015-10-01

While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings.

Three Cases of Spine Fractures after an Airplane Crash

Science.gov (United States)

Lee, Han Joo; Moon, Bong Ju; Pennant, William A.; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum

2015-01-01

While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings. PMID:27169094

Injury and side impact air bag deployment in near and far sided motor vehicle crashes, United States, 2000-2005.

Science.gov (United States)

Stadter, Greg; Grabowski, Jurek G; Burke, Christine; Aldaghlas, Tayseer A; Robinson, Linda; Fakhry, Samir M

2008-12-01

Side impact crashes, the most lethal type, account for 26% of all motor vehicle crashes in the United States. The purpose of this study is to delineate side impact airbag (SIAB) deployment rates, injury rates, and analyze crash factors associated with SIAB deployment and occupant injury. All passenger vehicles equipped with SIABs that were involved in a side impact crash were identified from the National Automotive Sampling System database. Crashes with multiple impacts, ejections, unbelted drivers or rollovers were excluded from the study. The outcome variables of interest were SIAB deployment and driver injury. SIAB deployment was compared in similar crashes to analyze the impact on driver's injury severity score. Other crash factors were also examined to analyze what role they play in SIAB deployment rates and injury rates, such as plane of contact, striking object and Delta-V. The data set for this study contained 247 drivers in near and far side crashes in vehicles with installed SIABs. Overall SIAB deployment was 43% in side impact crashes. A significant factor associated with both the SIAB deployment rate and the driver's injury rate was increased Delta-V. SIABs do not deploy consistently in crashes with a high Delta-V or with a lateral primary direction of force and a front plane of contact. In these two scenarios, further research is warranted on SIAB deployments. With SIAB deployment, it appears drivers are able to sustain a higher Delta-V impact without serious injury.

The risk of groundling fatalities from unintentional airplane crashes.

Science.gov (United States)

Thompson, K M; Rabouw, R F; Cooke, R M

2001-12-01

The crashes of four hijacked commercial planes on September 11, 2001, and the repeated televised images of the consequent collapse of the World Trade Center and one side of the Pentagon will inevitably change people's perceptions of the mortality risks to people on the ground from crashing airplanes. Goldstein and colleagues were the first to quantify the risk for Americans of being killed on the ground from a crashing airplane for unintentional events, providing average point estimates of 6 in a hundred million for annual risk and 4.2 in a million for lifetime risk. They noted that the lifetime risk result exceeded the commonly used risk management threshold of 1 in a million, and suggested that the risk to "groundlings" could be a useful risk communication tool because (a) it is a man-made risk (b) arising from economic activities (c) from which the victims derive no benefit and (d) exposure to which the victims cannot control. Their results have been used in risk communication. This analysis provides updated estimates of groundling fatality risks from unintentional crashes using more recent data and a geographical information system approach to modeling the population around airports. The results suggest that the average annual risk is now 1.2 in a hundred million and the lifetime risk is now 9 in ten million (below the risk management threshold). Analysis of the variability and uncertainty of this estimate, however, suggests that the exposure to groundling fatality risk varies by about a factor of approximately 100 in the spatial dimension of distance to an airport, with the risk declining rapidly outside the first 2 miles around an airport. We believe that the risk to groundlings from crashing airplanes is more useful in the context of risk communication when information about variability and uncertainty in the risk estimates is characterized, but we suspect that recent events will alter its utility in risk communication.

Multivariate poisson lognormal modeling of crashes by type and severity on rural two lane highways.

Science.gov (United States)

Wang, Kai; Ivan, John N; Ravishanker, Nalini; Jackson, Eric

2017-02-01

In an effort to improve traffic safety, there has been considerable interest in estimating crash prediction models and identifying factors contributing to crashes. To account for crash frequency variations among crash types and severities, crash prediction models have been estimated by type and severity. The univariate crash count models have been used by researchers to estimate crashes by crash type or severity, in which the crash counts by type or severity are assumed to be independent of one another and modelled separately. When considering crash types and severities simultaneously, this may neglect the potential correlations between crash counts due to the presence of shared unobserved factors across crash types or severities for a specific roadway intersection or segment, and might lead to biased parameter estimation and reduce model accuracy. The focus on this study is to estimate crashes by both crash type and crash severity using the Integrated Nested Laplace Approximation (INLA) Multivariate Poisson Lognormal (MVPLN) model, and identify the different effects of contributing factors on different crash type and severity counts on rural two-lane highways. The INLA MVPLN model can simultaneously model crash counts by crash type and crash severity by accounting for the potential correlations among them and significantly decreases the computational time compared with a fully Bayesian fitting of the MVPLN model using Markov Chain Monte Carlo (MCMC) method. This paper describes estimation of MVPLN models for three-way stop controlled (3ST) intersections, four-way stop controlled (4ST) intersections, four-way signalized (4SG) intersections, and roadway segments on rural two-lane highways. Annual Average Daily traffic (AADT) and variables describing roadway conditions (including presence of lighting, presence of left-turn/right-turn lane, lane width and shoulder width) were used as predictors. A Univariate Poisson Lognormal (UPLN) was estimated by crash type and

Structural integrity analysis of an Ignalina nuclear power plant building subjected to an airplane crash

International Nuclear Information System (INIS)

Dundulis, Gintautas; Kulak, Ronald F.; Marchertas, Algirdas; Uspuras, Eugenijus

2007-01-01

Recent terrorist attacks using commandeered commercial airliners on civil structures have raised the issue of the ability of nuclear power plants to survive the consequences of an airliner crash. The structural integrity analysis due to the effects of an aircraft crash on an Ignalina nuclear power plant (INPP) accident localization system (ALS) building is the subject of this paper. A combination of the finite element method and empirical relationships were used for the analysis. A global structural integrity analysis was performed for a portion of the ALS building using the dynamic loading from an aircraft crash impact model. The local effects caused by impact of the aircraft's engine on the building wall were evaluated independently by using an empirical formula. The results from the crash analysis of a twin engine commercial aircraft show that the impacted reinforced concrete wall of the ALS building will not have through-the-wall concrete failure, and the reinforcement will not fail. Strain-rate effects were found to delay the onset of cracking. Therefore, the structural integrity of the impacted wall of the INPP ALS building will be maintained during the crash event studied

Structural integrity analysis of an Ignalina nuclear power plant building subjected to an airplane crash

Energy Technology Data Exchange (ETDEWEB)

Dundulis, Gintautas [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, 3 Breslaujos, 44403 Kaunas-35 (Lithuania)]. E-mail: gintas@isag.lei.lt; Kulak, Ronald F. [RFK Engineering Mechanics Consultants (United States); Marchertas, Algirdas [Northern Illinois University (United States); Uspuras, Eugenijus [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, 3 Breslaujos, 44403 Kaunas-35 (Lithuania)

2007-08-15

Recent terrorist attacks using commandeered commercial airliners on civil structures have raised the issue of the ability of nuclear power plants to survive the consequences of an airliner crash. The structural integrity analysis due to the effects of an aircraft crash on an Ignalina nuclear power plant (INPP) accident localization system (ALS) building is the subject of this paper. A combination of the finite element method and empirical relationships were used for the analysis. A global structural integrity analysis was performed for a portion of the ALS building using the dynamic loading from an aircraft crash impact model. The local effects caused by impact of the aircraft's engine on the building wall were evaluated independently by using an empirical formula. The results from the crash analysis of a twin engine commercial aircraft show that the impacted reinforced concrete wall of the ALS building will not have through-the-wall concrete failure, and the reinforcement will not fail. Strain-rate effects were found to delay the onset of cracking. Therefore, the structural integrity of the impacted wall of the INPP ALS building will be maintained during the crash event studied.

Analyzing the effect of carbon fiber reinforced polymer on the crashworthiness of aluminum square hollow beam for crash box application

Science.gov (United States)

Raman, R.; Jayanth, K.; Sarkar, I.; Ravi, K.

2017-11-01

Crashworthiness of a material is a measure of its ability to absorb energy during a crash. A well-designed crash box is instrumental in protecting the costly vehicle components. A square, hollow, hybrid beam of aluminum/CFRP was subjected to dynamic axial load to analyze the effect of five different lay-up sequences on its crashworthiness. The beam was placed between two plates. Boundary conditions were imposed on them to simulate a frontal body crash test model. Modeling and dynamic analysis of composite structures was done on ABAQUS. Different orientation of carbon fibers varies the crashworthiness of the hybrid beam. Addition of CFRP layer showed clear improvement in specific energy absorption and crush force efficiency compared to pure aluminum beam. Two layers of CFRP oriented at 90° on Aluminum showed 52% increase in CFE.

Comparing crash trends and severity in the northern Rocky Mountain region.

Science.gov (United States)

2012-08-01

Safety Management Systems are federally mandated in an effort to encourage states to develop strategic programs in order to : mitigate severe crashes. In 2006, the Wyoming Department of Transportation (WYDOT) published the Wyoming Strategic Highway S...

Factors associated with crashes due to overcorrection or oversteering of vehicles

Directory of Open Access Journals (Sweden)

Praveena Penmetsa

2018-04-01

Full Text Available The objective of this research is to identify factors associated with crashes due to overcorrection or oversteering of vehicles. Crash data was collected from 2011 to 2013 for the State of North Carolina in the United States. Logistic regression modeling was used to analyze crash data because of the dichotomous nature of the dependent variable (overcorrection or oversteering. The crash involvement due to overcorrection or oversteering of a vehicle decreased as the age of the driver increased. Drivers are 2.22 times more likely to overcorrect or oversteer when ill, 3.44 times more likely to overcorrect or oversteer when under fatigue, and 1.61 times more likely to overcorrect or oversteer when fallen asleep compared to normal physical conditions. Overall, driver characteristics and speed limit tend to play a major role in overcorrection or oversteering of vehicles. Programs to reduce impaired driving might help in the reduction of overcorrection or oversteering related crash fatalities or injuries. Additionally, training and driver education programs focusing on identified factors associated with crashes due to overcorrection or oversteering of vehicles will benefit drivers on how to respond during emergency or panic situations. Keywords: Overcorrection, Oversteering, Vehicle, Logistic regression, Crash

Investigation of pedestrian crashes on two-way two-lane rural roads in Ethiopia.

Science.gov (United States)

Tulu, Getu Segni; Washington, Simon; Haque, Md Mazharul; King, Mark J

2015-05-01

Understanding pedestrian crash causes and contributing factors in developing countries is critically important as they account for about 55% of all traffic crashes. Not surprisingly, considerable attention in the literature has been paid to road traffic crash prediction models and methodologies in developing countries of late. Despite this interest, there are significant challenges confronting safety managers in developing countries. For example, in spite of the prominence of pedestrian crashes occurring on two-way two-lane rural roads, it has proven difficult to develop pedestrian crash prediction models due to a lack of both traffic and pedestrian exposure data. This general lack of available data has further hampered identification of pedestrian crash causes and subsequent estimation of pedestrian safety performance functions. The challenges are similar across developing nations, where little is known about the relationship between pedestrian crashes, traffic flow, and road environment variables on rural two-way roads, and where unique predictor variables may be needed to capture the unique crash risk circumstances. This paper describes pedestrian crash safety performance functions for two-way two-lane rural roads in Ethiopia as a function of traffic flow, pedestrian flows, and road geometry characteristics. In particular, random parameter negative binomial model was used to investigate pedestrian crashes. The models and their interpretations make important contributions to road crash analysis and prevention in developing countries. They also assist in the identification of the contributing factors to pedestrian crashes, with the intent to identify potential design and operational improvements. Copyright © 2015. Published by Elsevier Ltd.

A joint econometric analysis of seat belt use and crash-related injury severity.

Science.gov (United States)

Eluru, Naveen; Bhat, Chandra R

2007-09-01

This paper formulates a comprehensive econometric structure that recognizes two important issues in crash-related injury severity analysis. First, the impact of a factor on injury severity may be moderated by various observed and unobserved variables specific to an individual or to a crash. Second, seat belt use is likely to be endogenous to injury severity. That is, it is possible that intrinsically unsafe drivers do not wear seat belts and are the ones likely to be involved in high injury severity crashes because of their unsafe driving habits. The preceding issues are considered in the current research effort through the development of a comprehensive model of seat belt use and injury severity that takes the form of a joint correlated random coefficients binary-ordered response system. To our knowledge, this is the first instance of such a model formulation and application not only in the safety analysis literature, but in the econometrics literature in general. The empirical analysis is based on the 2003 General Estimates System (GES) data base. Several types of variables are considered to explain seat belt use and injury severity levels, including driver characteristics, vehicle characteristics, roadway design attributes, environmental factors, and crash characteristics. The results, in addition to confirming the effects of various explanatory variables, also highlight the importance of (a) considering the moderating effects of unobserved individual/crash-related factors on the determinants of injury severity and (b) seat belt use endogeneity. From a policy standpoint, the results suggest that seat belt non-users, when apprehended in the act, should perhaps be subjected to both a fine (to increase the chances that they wear seat belts) as well as mandatory enrollment in a defensive driving course (to attempt to change their aggressive driving behaviors).

Social costs of road crashes : an international analysis.

NARCIS (Netherlands)

Wijnen, W. & Stipdonk, H.L.

2016-01-01

This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income

Allegheny County Crash Data

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2016. Fields include injury severity,...

Allegheny County Crash Data

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2017. Fields include injury severity,...

Linear regression crash prediction models : issues and proposed solutions.

Science.gov (United States)

2010-05-01

The paper develops a linear regression model approach that can be applied to : crash data to predict vehicle crashes. The proposed approach involves novice data aggregation : to satisfy linear regression assumptions; namely error structure normality ...

Behaviour of a spent fuel transport-storage cask during an airplane crash

International Nuclear Information System (INIS)

Malesys, P.

1994-01-01

TRANSNUCLEAIRE has got an order for the design and manufacturing of dual purpose, transport and storage, casks for spent fuel.An original item of the qualification of the design of this cask, for the storage aspect, is the necessity to demonstrate the resistance to an air crash.The typical case taken into account for design is the crash of a military fighter (F16) with a total mass of 14600kg and an impact speed of 150ms -1 . The demonstration of the ability of the cask to withstand this test is provided by both calculation and test.Two cases were considered. For the first one, the projectile hits the cask at the centre of the anti-crash lid. For the second one, it hits the cask in the plane of the closure system.The first step of the qualification is based on calculations performed with a code designed to study the effects of crashes. The aim of the calculations is, mainly, to determine the missile which has to be shot, and to select the worst orientation for the impact.To provide a full justification of the acceptability of the impact as concerned leaktightness, a test has been performed on a one-third scale model. It has shown that it was not altered by the impact.The paper provides a full description of the method of analysis, results of the numerical analysis, conclusion of the test and how the combination of calculation and test demonstrates the ability of the cask to withstand an airplane crash. ((orig.))

Analysing the Severity and Frequency of Traffic Crashes in Riyadh City Using Statistical Models

Directory of Open Access Journals (Sweden)

Saleh Altwaijri

2012-12-01

Full Text Available Traffic crashes in Riyadh city cause losses in the form of deaths, injuries and property damages, in addition to the pain and social tragedy affecting families of the victims. In 2005, there were a total of 47,341 injury traffic crashes occurred in Riyadh city (19% of the total KSA crashes and 9% of those crashes were severe. Road safety in Riyadh city may have been adversely affected by: high car ownership, migration of people to Riyadh city, high daily trips reached about 6 million, high rate of income, low-cost of petrol, drivers from different nationalities, young drivers and tremendous growth in population which creates a high level of mobility and transport activities in the city. The primary objective of this paper is therefore to explore factors affecting the severity and frequency of road crashes in Riyadh city using appropriate statistical models aiming to establish effective safety policies ready to be implemented to reduce the severity and frequency of road crashes in Riyadh city. Crash data for Riyadh city were collected from the Higher Commission for the Development of Riyadh (HCDR for a period of five years from 1425H to 1429H (roughly corresponding to 2004-2008. Crash data were classified into three categories: fatal, serious-injury and slight-injury. Two nominal response models have been developed: a standard multinomial logit model (MNL and a mixed logit model to injury-related crash data. Due to a severe underreporting problem on the slight injury crashes binary and mixed binary logistic regression models were also estimated for two categories of severity: fatal and serious crashes. For frequency, two count models such as Negative Binomial (NB models were employed and the unit of analysis was 168 HAIs (wards in Riyadh city. Ward-level crash data are disaggregated by severity of the crash (such as fatal and serious injury crashes. The results from both multinomial and binary response models are found to be fairly consistent but

Characteristics of cyclist crashes in Italy using latent class analysis and association rule mining.

Directory of Open Access Journals (Sweden)

Gabriele Prati

Full Text Available The factors associated with severity of the bicycle crashes may differ across different bicycle crash patterns. Therefore, it is important to identify distinct bicycle crash patterns with homogeneous attributes. The current study aimed at identifying subgroups of bicycle crashes in Italy and analyzing separately the different bicycle crash types. The present study focused on bicycle crashes that occurred in Italy during the period between 2011 and 2013. We analyzed categorical indicators corresponding to the characteristics of infrastructure (road type, road signage, and location type, road user (i.e., opponent vehicle and cyclist's maneuver, type of collision, age and gender of the cyclist, vehicle (type of opponent vehicle, and the environmental and time period variables (time of the day, day of the week, season, pavement condition, and weather. To identify homogenous subgroups of bicycle crashes, we used latent class analysis. Using latent class analysis, the bicycle crash data set was segmented into 19 classes, which represents 19 different bicycle crash types. Logistic regression analysis was used to identify the association between class membership and severity of the bicycle crashes. Finally, association rules were conducted for each of the latent classes to uncover the factors associated with an increased likelihood of severity. Association rules highlighted different crash characteristics associated with an increased likelihood of severity for each of the 19 bicycle crash types.

Integrated traffic conflict model for estimating crash modification factors.

Science.gov (United States)

Shahdah, Usama; Saccomanno, Frank; Persaud, Bhagwant

2014-10-01

Crash modification factors (CMFs) for road safety treatments are usually obtained through observational models based on reported crashes. Observational Bayesian before-and-after methods have been applied to obtain more precise estimates of CMFs by accounting for the regression-to-the-mean bias inherent in naive methods. However, sufficient crash data reported over an extended period of time are needed to provide reliable estimates of treatment effects, a requirement that can be a challenge for certain types of treatment. In addition, these studies require that sites analyzed actually receive the treatment to which the CMF pertains. Another key issue with observational approaches is that they are not causal in nature, and as such, cannot provide a sound "behavioral" rationale for the treatment effect. Surrogate safety measures based on high risk vehicle interactions and traffic conflicts have been proposed to address this issue by providing a more "causal perspective" on lack of safety for different road and traffic conditions. The traffic conflict approach has been criticized, however, for lacking a formal link to observed and verified crashes, a difficulty that this paper attempts to resolve by presenting and investigating an alternative approach for estimating CMFs using simulated conflicts that are linked formally to observed crashes. The integrated CMF estimates are compared to estimates from an empirical Bayes (EB) crash-based before-and-after analysis for the same sample of treatment sites. The treatment considered involves changing left turn signal priority at Toronto signalized intersections from permissive to protected-permissive. The results are promising in that the proposed integrated method yields CMFs that closely match those obtained from the crash-based EB before-and-after analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Systematic review of military motor vehicle crash-related injuries.

Science.gov (United States)

Krahl, Pamela L; Jankosky, Christopher J; Thomas, Richard J; Hooper, Tomoko I

2010-01-01

Motor vehicle crashes account for nearly one third of U.S. military fatalities annually. The objective of this review is to summarize the published evidence on injuries due specifically to military motor vehicle (MMV) crashes. A search of 18 electronic databases identified English language publications addressing MMV crash-related injuries between 1970 and 2006 that were available to the general public. Documents limited in distribution to military or government personnel were not evaluated. Relevant articles were categorized by study design. The search identified only 13 studies related specifically to MMV crashes. Most were case reports or case series (n=8); only one could be classified as an intervention study. Nine of the studies were based solely on data from service-specific military safety centers. Few studies exist on injuries resulting from crashes of military motor vehicles. Epidemiologic studies that assess injury rates, type, severity, and risk factors are needed, followed by studies to evaluate targeted interventions and prevention strategies. Interventions currently underway should be evaluated for effectiveness, and those proven effective in the civilian community, such as graduated driver licensing, should be considered for implementation and evaluation in military populations. Published by Elsevier Inc.

Road Crashes in Addis Ababa, Ethiopia: Empirical Findings ...

African Journals Online (AJOL)

Nneka Umera-Okeke

studies on road crashes forecasted road traffic fatalities to be the second ... Ethiopia's capital city – shares 60% out of the total number of vehicles in the ... network density and vehicle ownership, the country (Ethiopia) has been cited as ... crash related injury case confirmation. ..... to thank you in advance for your cooperation!

Response of equipment in nuclear power plants to airplane crash

International Nuclear Information System (INIS)

Schalk, M.; Woelfel, H.

1976-01-01

Nuclear power plants in Germany are to be designed against airplane crash. Two problems arise: first, the local problem of penetration as well as local destruction of the building and secondly the airplane induced vibrations of the whole building which cause loadings for secondary systems (equipment). This paper deals especially with the second problem. Floor response spectra due to airplane crash are presented for two different power plant buildings. The influence of various parameters (time history of excitation, direction and location of impact, mathematical model, soil, damping, etc.) are discussed. A comparison with the results of earthquake loading is given. Suggestions are made for developing suitable floor design spectra and using them to analyse multidegree-of-freedom systems. However, the paper gives only a partial answer to the questions arising because of some important restrictions which had to be made. Studies concerning these restrictions are still being conducted and will be presented in a separate paper. (Auth.)

Increased inequality in mortality from road crashes among Arabs and Jews in Israel.

Science.gov (United States)

Magid, Avi; Leibovitch-Zur, Shalhevet; Baron-Epel, Orna

2015-01-01

Previous studies in several countries have shown that the economically disadvantaged seem to have a greater risk of being involved in a car crash. The aim of the present study was to compare rates and trends in mortality and injury from road crashes by age among the Arab and Jewish populations in Israel. Data on road crashes with casualties (2003-2011) from the Israeli Central Bureau of Statistics were analyzed. Age-adjusted road crash injury rates and mortality rates for 2003 to 2011 were calculated and time trends for each age group and population group are presented. Time trend significance was evaluated by linear regression models. Arabs in Israel are at increased risk of injury and mortality from road crashes compared to Jews. Road crash injury rates have significantly decreased in both populations over the last decade, although the rates have been persistently higher among Arabs. Road crash mortality rates have also decreased significantly in the Jewish population but not in the Arab population. This implies an increase in the disparity in mortality between Jews and Arabs. The most prominent differences in road crash injury and mortality rates between Arabs and Jews can be observed in young adults and young children. The reduction in road crashes in the last decade is a positive achievement. However, the reductions are not equal among Arabs and Jews in Israel. Therefore, an increase in the disparities in mortality from road crashes is apparent. Public health efforts need to focus specifically on decreasing road crashes in the Arab community.

Minor Crashes and ‘Whiplash’ in the United States

OpenAIRE

Bartsch, Adam J.; Gilbertson, Lars G.; Prakash, Vikas; Morr, Douglas R.; Wiechel, John F.

2008-01-01

In the United States there is currently a paucity of available real world minor rear crash data with struck vehicle delta-V, or speed change, less than or equal to 15 kilometers per hour. These data are essential as researchers attempt to define ‘whiplash’ injury risk potential in these minor crashes. This study analyzed a new set of 105 U.S. minor rear aligned crashes between passenger vehicles. Mean struck vehicle delta-V and acceleration were 6.3 km/h (s.d. = 2.1 km/h) and 1.4g (s.d. = 0.5...

Projecting Fatalities in Crashes Involving Older Drivers, 2000-2025

Energy Technology Data Exchange (ETDEWEB)

Hu, P.S.

2001-03-23

As part of this research effort, we developed a new methodology for projecting elderly traffic crash fatalities. This methodology separates exposure to crashes from crash risk per se, and further divides exposure into two components, the number of miles driven and the likelihood of being a driver. This component structure permits conceptually different determinants of traffic fatalities to be projected separately and has thorough motivation in behavioral theory. It also permits finer targeting of particular aspects of projections that need improvement and closer linking of projections to possible policy instruments for influencing them.

Risk factors associated with high potential for serious crashes.

Science.gov (United States)

2015-09-01

Crashes are random events and low traffic volumes therefore dont always make crash hot-spot : identification possible. This project has used extensive data collection and analysis for a large sample : of Oregons low volume roads to develop a ri...

Trends and projections of vehicle crash related fatalities and injuries in Northwest Gondar, Ethiopia: A time series analysis

Directory of Open Access Journals (Sweden)

Solomon Meseret Woldeyohannes

2014-01-01

Conclusion: The numbers of lives lost and disabilities due to vehicle crashes indicated an upward trend in the last decade showing future burden in terms of societal and economic costs threatening the lives of many individuals. Surveillance systems that could enable to monitor patterns of vehicle crashes with preventive strategies must be established.

Structural Integrity Assessment of Reactor Containment Subjected to Aircraft Crash

International Nuclear Information System (INIS)

Kim, Junyong; Chang, Yoonsuk

2013-01-01

When an accident occurs at the NPP, containment building which acts as the last barrier should be assessed and analyzed structural integrity by internal loading or external loading. On many occasions that can occur in the containment internal such as LOCA(Loss Of Coolant Accident) are already reflected to design. Likewise, there are several kinds of accidents that may occur from the outside of containment such as earthquakes, hurricanes and strong wind. However, aircraft crash that at outside of containment is not reflected yet in domestic because NPP sites have been selected based on the probabilistic method. After intentional aircraft crash such as World Trade Center and Pentagon accident in US, social awareness for safety of infrastructure like NPP was raised world widely and it is time for assessment of aircraft crash in domestic. The object of this paper is assessment of reactor containment subjected to aircraft crash by FEM(Finite Element Method). In this paper, assessment of structural integrity of containment building subjected to certain aircraft crash was carried out. Verification of structure integrity of containment by intentional severe accident. Maximum stress 61.21MPa of horizontal shell crash does not penetrate containment. Research for more realistic results needed by steel reinforced concrete model

Investigation of Roadway Geometric and Traffic Flow Factors for Vehicle Crashes Using Spatiotemporal Interaction

Science.gov (United States)

Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.

2017-09-01

Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.

INVESTIGATION OF ROADWAY GEOMETRIC AND TRAFFIC FLOW FACTORS FOR VEHICLE CRASHES USING SPATIOTEMPORAL INTERACTION

Directory of Open Access Journals (Sweden)

G. Gill

2017-09-01

Full Text Available Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.

A different perspective on conspicuity related motorcycle crashes.

Science.gov (United States)

de Craen, Saskia; Doumen, Michelle J A; van Norden, Yvette

2014-02-01

The most common type of conflict in which a motorcyclist is injured or killed is a collision between a motorcycle and a car, often in priority situations. Many studies on motorcycle safety focus on the question why car drivers fail to give priority and on the poor conspicuity of motorcycles. The concept of 'looked-but-failed-to-see' crashes is a recurring item. On the other hand, it is not entirely unexpected that motorcycles have many conflicts with cars; there simply are so many cars on the road. This paper tries to unravel whether - acknowledging the differences in exposure - car drivers indeed fail to yield for motorcycles more often than for other cars. For this purpose we compared the causes of crashes on intersections (e.g. failing to give priority, speeding, etc.) between different crash types (car-motorcycle or car-car). In addition, we compared the crash causes of dual drivers (i.e. car drivers who also have their motorcycle licence) with regular car drivers. Our crash analysis suggests that car drivers do not fail to give priority to motorcycles relatively more often than to another car when this car/motorcycle approaches from a perpendicular angle. There is only one priority situation where motorcycles seem to be at a disadvantage compared to cars. This is when a car makes a left turn, and fails to give priority to an oncoming motorcycle. This specific crash scenario occurs more often when the oncoming vehicle is a motorcycle than when it is a car. We did not find a significant difference between dual drivers and regular car drivers in how often they give priority to motorcycles compared to cars. Copyright © 2013 Elsevier Ltd. All rights reserved.

School start times and teenage driver motor vehicle crashes.

Science.gov (United States)

2015-12-01

There is substantial evidence that lack of sleep is a significant factor in motor vehicle crashes experienced by teenage drivers. This report examines the hypothesis that a later high school start time may reduce crash rates by reducing the interfere...

Analysis of Traffic Crash Data in Kentucky (2012-2016).

Science.gov (United States)

2017-09-01

This report documents an analysis of traffic crash data in Kentucky for the years of 2012 through 2016. A primary objective of this study was to determine average crash statistics for Kentucky highways. Rates were calculated for various types of high...

Analysis of traffic crash data in Kentucky (2009-2013).

Science.gov (United States)

2014-09-01

This report documents an analysis of traffic crash data in Kentucky for the years of 2009 through 2013. A primary objective of this study was to determine average crash statistics for Kentucky highways. Rates were calculated for various types of high...

Drug and alcohol crash risk : a case-control study.

Science.gov (United States)

2016-12-01

This study used a case-control design to estimate the risk of crashes involving drivers using drugs, alcohol or both. Data was collected in Virginia Beach, Virginia, for 20 months. The study obtained biological measures on more than 3,000 crash...

Application of a bus seat buffer to mitigate frontal crash effects

Science.gov (United States)

Stanisławek, Sebastian; Dziewulski, Paweł; Sławiński, Grzegorz

2018-01-01

The paper considers the problem of coach occupant safety during crash events. The authors present a simple low-cost seat buffer concept which may mitigate the effects of frontal impact. The method of computer simulation was chosen to solve the problem efficiently. The Finite Element Method (FEM) implemented in the LS-DYNA commercial code was used. The testing procedure was based on European Commission regulations, under which vehicles move at a defined speed. Simulations have shown that seat occupants suffer serious trauma during a crash, with the head experiencing relatively high acceleration, thus resulting in an HIC36 of 1490. The installation of a protective buffer mounted on the upper part of the seat reduced the HIC36 to only 510. However, in its current form it does not meet the requirements of the regulations. Further modifications to the overlay shape and structure are essential in order to better improve the deceleration of passengers' bodies. Moreover, a detailed model of seats and their anchorage should be taken into account. A more flexible structure should provide more positive and more accurate results.

Compulsive Cell Phone Use and History of Motor Vehicle Crash

Science.gov (United States)

O’Connor, Stephen S.; Whitehill, Jennifer M.; King, Kevin M.; Kernic, Mary A.; Boyle, Linda Ng; Bresnahan, Brian; Mack, Christopher D.; Ebel, Beth E.

2013-01-01

Introduction Few studies have examined the psychological factors underlying the association between cell phone use and motor vehicle crash. We sought to examine the factor structure and convergent validity of a measure of problematic cell phone use and explore whether compulsive cell phone use is associated with a history of motor vehicle crash. Methods We recruited a sample of 383 undergraduate college students to complete an on-line assessment that included cell phone use and driving history. We explored the dimensionality of the Cell Phone Overuse Scale (CPOS) using factor analytic methods. Ordinary least squares regression models were used to examine associations between identified subscales and measures of impulsivity, alcohol use, and anxious relationship style to establish convergent validity. We used negative binomial regression models to investigate associations between the CPOS and motor vehicle crash incidence. Results We found the CPOS to be comprised of four subscales: anticipation, activity interfering, emotional reaction, and problem recognition. Each displayed significant associations with aspects of impulsivity, problematic alcohol use, and anxious relationship style characteristics. Only the anticipation subscale demonstrated statistically significant associations with reported motor vehicle crash incidence, controlling for clinical and demographic characteristics (RR 1.13, CI 1.01 to 1.26). For each one-point increase on the 6-point anticipation subscale, risk for previous motor vehicle crash increased by 13%. Conclusions Crash risk is strongly associated with heightened anticipation about incoming phone calls or messages. The mean score on the CPOS is associated with increased risk of motor vehicle crash but does not reach statistical significance. PMID:23910571

Crash risk analysis during fog conditions using real-time traffic data.

Science.gov (United States)

Wu, Yina; Abdel-Aty, Mohamed; Lee, Jaeyoung

2018-05-01

This research investigates the changes of traffic characteristics and crash risks during fog conditions. Using real-time traffic flow and weather data at two regions in Florida, the traffic patterns at the fog duration were compared to the traffic patterns at the clear duration. It was found that the average 5-min speed and the average 5-min volume were prone to decreasing during fog. Based on previous studies, a "Crash Risk Increase Indicator (CRII)" was proposed to explore the differences of crash risk between fog and clear conditions. A binary logistic regression model was applied to link the increase of crash risks with traffic flow characteristics. The results suggested that the proposed indicator worked well in evaluating the increase of crash risk under fog condition. It was indicated that the crash risk was prone to increase at ramp vicinities in fog conditions. Also, the average 5-min volume during fog and the lane position are important factors for crash risk increase. The differences between the regions were also explored in this study. The results indicated that the locations with heavier traffic or locations at the lanes that were closest to the median in Region 2 were more likely to observe an increase in crash risks in fog conditions. It is expected that the proposed indicator can help identify the dangerous traffic status under fog conditions and then proper ITS technologies can be implemented to enhance traffic safety when the visibility declines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Differences in Factors Affecting Various Crash Types with High Numbers of Fatalities and Injuries in China

Science.gov (United States)

Wang, Kai; He, Jie; Ding, Jianxun; Shi, Qin; Wang, Changjun; Li, Pingfan

2016-01-01

Objectives Road traffic crashes that involve very high numbers of fatalities and injuries arouse public concern wherever they occur. In China, there are two categories of such crashes: a crash that results in 10–30 fatalities, 50–100 serious injuries or a total cost of 50–100 million RMB ($US8-16m) is a “serious road traffic crash” (SRTC), while a crash that is even more severe or costly is a “particularly serious road traffic crash” (PSRTC). The aim of this study is to identify the main factors affecting different types of these crashes (single-vehicle, head-on, rear-end and side impact) with the ultimate goal of informing prevention activities and policies. Methods Detailed descriptions of the SRTCs and PSRTCs that occurred from 2007 to 2014 were collected from the database “In-depth Investigation and Analysis System for Major Road Traffic Crashes” (IIASMRTC), which is maintained by the Traffic Management Research Institute of the Ministry of Public Security of China (TMRI). 18 main risk factors, which were categorized into four areas (participant, vehicle, road and environment-related) were chosen as potential independent variables for the multinomial logistic regression analysis. Comparisons were made among the single-vehicle, head-on, rear-end and side impact crashes in terms of factors affecting crash occurrence. Findings Five risk factors were significant for the six multinomial logistic regression models, which were location, vertical alignment, roadside safety rating, driver distraction and overloading of cargo. It was indicated that intersections were more likely to have side impact SRTCs and PSRTCs, especially with poor visibility at night. Overloaded freight vehicles were more likely to be involved in a rear-end crash than other freight vehicles. Driver distraction is an important risk factor for head-on crashes, while vertical alignment and roadside safety rating are positively associated with single-vehicle crashes. Conclusion Based

Analysis of hourly crash likelihood using unbalanced panel data mixed logit model and real-time driving environmental big data.

Science.gov (United States)

Chen, Feng; Chen, Suren; Ma, Xiaoxiang

2018-06-01

Driving environment, including road surface conditions and traffic states, often changes over time and influences crash probability considerably. It becomes stretched for traditional crash frequency models developed in large temporal scales to capture the time-varying characteristics of these factors, which may cause substantial loss of critical driving environmental information on crash prediction. Crash prediction models with refined temporal data (hourly records) are developed to characterize the time-varying nature of these contributing factors. Unbalanced panel data mixed logit models are developed to analyze hourly crash likelihood of highway segments. The refined temporal driving environmental data, including road surface and traffic condition, obtained from the Road Weather Information System (RWIS), are incorporated into the models. Model estimation results indicate that the traffic speed, traffic volume, curvature and chemically wet road surface indicator are better modeled as random parameters. The estimation results of the mixed logit models based on unbalanced panel data show that there are a number of factors related to crash likelihood on I-25. Specifically, weekend indicator, November indicator, low speed limit and long remaining service life of rutting indicator are found to increase crash likelihood, while 5-am indicator and number of merging ramps per lane per mile are found to decrease crash likelihood. The study underscores and confirms the unique and significant impacts on crash imposed by the real-time weather, road surface, and traffic conditions. With the unbalanced panel data structure, the rich information from real-time driving environmental big data can be well incorporated. Copyright © 2018 National Safety Council and Elsevier Ltd. All rights reserved.

Crash fatality risk and unibody versus body-on-frame structure in SUVs.

Science.gov (United States)

Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara

2014-09-01

In crashes between cars and SUVs, car occupants are more likely to be killed than if they crashed with another car. An increasing proportion of SUVs are built with unibody, rather than truck-like body-on-frame construction. Unibody SUVs are generally lighter, less stiff, and less likely to roll over than body-on-frame SUVs, but whether unibody structure affects risk of death in crashes is unknown. To determine whether unibody SUVs differ from body-on-frame SUVs in the danger they pose to occupants of other vehicles and in the self-protection they offer to their own occupants. Case-control study of crashes between one compact SUV and one other passenger vehicle in the US during 1995-2008, in which the SUV was model year 1996-2006. Cases were all decedents in fatal crashes, one control was selected from each non-fatal crash. Occupants of passenger vehicles that crashed with compact unibody SUVs were at 18% lower risk of death compared to those that crashed with compact body-on-frame SUVs (adjusted odds ratio 0.82 (95% confidence interval 0.73-0.94)). Occupants of compact unibody SUVs were also at lower risk of death compared to occupants of body-on-frame SUVs (0.86 (0.72-1.02)). In two-vehicle collisions involving compact SUVs, unibody structure was associated with lower risk of death both in occupants of other vehicles in the crash, and in SUVs' own occupants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Traffic crash involvement: experiential driving knowledge and stressful contextual antecedents.

Science.gov (United States)

Legree, Peter J; Heffner, Tonia S; Psotka, Joseph; Martin, Daniel E; Medsker, Gina J

2003-02-01

Researchers have rarely examined stressful environments and psychological characteristics as predictors of driving behavior in the same study. The authors hypothesized that (a) safer drivers more accurately assess physical and emotional traffic hazards and (b) stress and emotional states elevate crash risk. The hypotheses were evaluated with procedural and declarative tacit driving knowledge tests requiring assessment of emotional and contextual hazards and with accident reports describing crash antecedents, including stressful events and environmental conditions. Analyses identified separate driving knowledge factors corresponding to emotional and contextual hazards that were significantly related to the crash criteria. Accident report analyses show that stress significantly elevates at-fault crash risk. The results demonstrate the importance of experiential knowledge acquired without instruction (procedural or tacit knowledge) and provide safety recommendations.

Alcohol-related predictors of adolescent driving: gender differences in crashes and offenses.

Science.gov (United States)

Shope, J T; Waller, P F; Lang, S W

1996-11-01

Demographic and alcohol-related data collected from eight-grade students (age 13 years) were used in logistic regression to predict subsequent first-year driving crashes and offenses (age 17 years). For young men's crashes and offenses, good-fitting models used living situation (both parents or not), parents' attitude about teen drinking (negative or neutral), and the interaction term. Young men who lived with both parents and reported negative parental attitudes regarding teen drinking were less likely to have crashes and offenses. For young women's crashes, a good-fitting model included friends' involvement with alcohol. Young women who reported that their friends were not involved with alcohol were least likely to have crashes. No model predicting young women's offenses emerged.

Protection of children restrained in child safety seats in side impact crashes.

Science.gov (United States)

Arbogast, Kristy B; Locey, Caitlin M; Zonfrillo, Mark R; Maltese, Matthew R

2010-10-01

The performance of child restraint systems (CRS) in side impact motor vehicle crashes has been under study due to the injury and fatality burden of these events. Although previous research has quantified injury risk or described injured body regions, safety advances require an understanding of injury causation. Therefore, the objective was to delineate injury causation scenarios for CRS-restrained children in side impacts and document probable contact points in the vehicle interior. Two in-depth crash investigation databases, the Crash Injury Research and Engineering Network and the Partners for Child Passenger Safety Study, were queried for rear-seated, CRS-restrained children in side impact crashes who sustained Abbreviated Injury Scale 2+ injury. These cases were reviewed by a multidisciplinary team of physicians and engineers to describe injury patterns, injury causation, and vehicle components that contributed to the injuries. Forty-one occupants (average age, 2.6 years) met the inclusion criteria. Twenty-four were near side to the crash, 7 were far side, and 10 were center seated. The most common injuries were to the skull and brain with an increasing proportion of skull fracture as age increased. Head and spine injuries without evidence of head contact were rare but present. All thoracic injuries were lung contusions and no rib fractures occurred. Near-side head and face contacts points were along the rear vertical plane of the window and the horizontal plane of the window sill. Head and face contact points for center- and far-side occupants were along the edges of the front seat back and front seat head restraint. Head injuries are the target for injury prevention for children in CRS in side impact crashes. Most of these injuries are due to the contact; for near-side occupants, contact with the CRS structure and the door interior, for far- or center-seated occupants, contact with the front seat back. These data are useful in developing both educational and

A market systems analysis of the U.S. Sport Utility Vehicle market considering frontal crash safety technology and policy.

Science.gov (United States)

Hoffenson, Steven; Frischknecht, Bart D; Papalambros, Panos Y

2013-01-01

Active safety features and adjustments to the New Car Assessment Program (NCAP) consumer-information crash tests have the potential to decrease the number of serious traffic injuries each year, according to previous studies. However, literature suggests that risk reductions, particularly in the automotive market, are often accompanied by adjusted consumer risk tolerance, and so these potential safety benefits may not be fully realized due to changes in consumer purchasing or driving behavior. This article approaches safety in the new vehicle market, particularly in the Sport Utility Vehicle and Crossover Utility Vehicle segments, from a market systems perspective. Crash statistics and simulations are used to predict the effects of design and policy changes on occupant crash safety, and discrete choice experiments are conducted to estimate the values consumers place on vehicle attributes. These models are combined in a market simulation that forecasts how consumers respond to the available vehicle alternatives, resulting in predictions of the market share of each vehicle and how the change in fleet mixture influences societal outcomes including injuries, fuel consumption, and firm profits. The model is tested for a scenario where active safety features are implemented across the new vehicle fleet and a scenario where the U.S. frontal NCAP test speed is modified. While results exhibit evidence of consumer risk adjustment, they support adding active safety features and lowering the NCAP frontal test speed, as these changes are predicted to improve the welfare of both firms and society. Copyright © 2012 Elsevier Ltd. All rights reserved.

Prediction equation for vehicle-pedestrian crash and safety analysis ...

African Journals Online (AJOL)

The occurrences of vehicle-pedestrian crashes at signalized intersections were investigated using a 3 year (2004-2006) crash records of 82 signalized intersections in Accra, Kumasi, Tema, Sekondi-Takoradi and Tamale. The data were analyzed using Micro-computer Accident Analysis Package. Traffic flow characteristics ...

Injury severity in delivery-motorcycle to vehicle crashes in the Seoul metropolitan area.

Science.gov (United States)

Chung, Younshik; Song, Tai-Jin; Yoon, Byoung-Jo

2014-01-01

More than 56% of motorcycles in Korea are used for the purpose of delivering parcels and food. Since such delivery requires quick service, most motorcyclists commit traffic violations while delivering, such as crossing the centerline, speeding, running a red light, and driving in the opposite direction down one-way streets. In addition, the fatality rate for motorcycle crashes is about 12% of the fatality rate for road traffic crashes, which is considered to be high, although motorcycle crashes account for only 5% of road traffic crashes in South Korea. Therefore, the objective of this study is to analyze the injury severity of vehicle-to-motorcycle crashes that have occurred during delivery. To examine the risk of different injury levels sustained under all crash types of vehicle-to-motorcycle, this study applied an ordered probit model. Based on the results, this study proposes policy implications to reduce the injury severity of vehicle-to-motorcycle crashes during delivery. Copyright © 2013 Elsevier Ltd. All rights reserved.

Helicopter crashes into water: warning time, final position, and other factors affecting survival.

Science.gov (United States)

Brooks, Christopher J; MacDonald, Conor V; Baker, Susan P; Shanahan, Dennis F; Haaland, Wren L

2014-04-01

According to 40 yr of data, the fatality rate for a helicopter crash into water is approximately 25%. Does warning time and the final position of the helicopter in the water influence the survival rate? The National Transportation Safety Board (NTSB) database was queried to identify helicopter crashes into water between 1981 and 2011 in the Gulf of Mexico and Hawaii. Fatality rate, amount of warning time prior to the crash, and final position of the helicopter were identified. There were 133 helicopters that crashed into water with 456 crew and passengers. Of these, 119 occupants (26%) did not survive; of those who did survive, 38% were injured. Twelve died after making a successful escape from the helicopter. Crashes with 1 min. However, more than half of fatalities (57%) came from crashes for which the warning time could not be determined. Lack of warning time and how to survive in the water after the crash should be a topic for study in all marine survival/aircraft ditching courses. Investigators should be trained to provide estimates of warning time when investigating helicopter crashes into water.

A comprehensive analysis of factors influencing the injury severity of large-truck crashes.

Science.gov (United States)

Zhu, Xiaoyu; Srinivasan, Sivaramakrishnan

2011-01-01

Given the importance of trucking to the economic well being of a country and the safety concerns posed by the trucks, a study of large-truck crashes is critical. This paper contributes by undertaking an extensive analysis of the empirical factors affecting injury severity of large-truck crashes. Data from a recent, nationally representative sample of large-truck crashes are examined to determine the factors affecting the overall injury severity of these crashes. The explanatory factors include the characteristics of the crash, vehicle(s), and the driver(s). The injury severity was modeled using two measures. Several similarities and some differences were observed across the two models which underscore the need for improved accuracy in the assessment of injury severity of crashes. The estimated models capture the marginal effects of a variety of explanatory factors simultaneously. In particular, the models indicate the impacts of several driver behavior variables on the severity of the crashes, after controlling for a variety of other factors. For example, driver distraction (truck drivers), alcohol use (car drivers), and emotional factors (car drivers) are found to be associated with higher severity crashes. A further interesting finding is the strong statistical significance of several dummy variables that indicate missing data - these reflect how the nature of the crash itself could affect the completeness of the data. Future efforts should seek to collect such data more comprehensively so that the true effects of these aspects on the crash severity can be determined. Copyright © 2010 Elsevier Ltd. All rights reserved.

Bayesian log-periodic model for financial crashes

DEFF Research Database (Denmark)

Rodríguez-Caballero, Carlos Vladimir; Knapik, Oskar

2014-01-01

This paper introduces a Bayesian approach in econophysics literature about financial bubbles in order to estimate the most probable time for a financial crash to occur. To this end, we propose using noninformative prior distributions to obtain posterior distributions. Since these distributions...... cannot be performed analytically, we develop a Markov Chain Monte Carlo algorithm to draw from posterior distributions. We consider three Bayesian models that involve normal and Student’s t-distributions in the disturbances and an AR(1)-GARCH(1,1) structure only within the first case. In the empirical...... part of the study, we analyze a well-known example of financial bubble – the S&P 500 1987 crash – to show the usefulness of the three methods under consideration and crashes of Merval-94, Bovespa-97, IPCMX-94, Hang Seng-97 using the simplest method. The novelty of this research is that the Bayesian...

Trends in teen driver licensure, driving patterns and crash involvement in the United States, 2006-2015.

Science.gov (United States)

Shults, Ruth A; Williams, Allan F

2017-09-01

The Monitoring the Future (MTF) survey provides nationally-representative annual estimates of licensure and driving patterns among U.S. teens. A previous study using MTF data reported substantial declines in the proportion of high school seniors that were licensed to drive and increases in the proportion of nondrivers following the recent U.S. economic recession. To explore whether licensure and driving patterns among U.S. high school seniors have rebounded in the post-recession years, we analyzed MTF licensure and driving data for the decade of 2006-2015. We also examined trends in teen driver involvement in fatal and nonfatal injury crashes for that decade using data from the Fatality Analysis Reporting System and National Automotive Sampling System General Estimates System, respectively. During 2006-2015, the proportion of high school seniors that reported having a driver's license declined by 9 percentage points (11%) from 81% to 72% and the proportion that did not drive during an average week increased by 8 percentage points (44%) from 18% to 26%. The annual proportion of black seniors that did not drive was consistently greater than twice the proportion of nondriving white seniors. Overall during the decade, 17- and 18-year-old drivers experienced large declines in fatal and nonfatal injury crashes, although crashes increased in both 2014 and 2015. The MTF data indicate that licensure and driving patterns among U.S. high school seniors have not rebounded since the economic recession. The recession had marked negative effects on teen employment opportunities, which likely influenced teen driving patterns. Possible explanations for the apparent discrepancies between the MTF data and the 2014 and 2015 increases in crashes are explored. MTF will continue to be an important resource for clarifying teen driving trends in relation to crash trends and informing strategies to improve teen driver safety. Published by Elsevier Ltd.

Estimating motor carrier management information system crash file underreporting from carrier records : research brief.

Science.gov (United States)

2017-08-01

This study estimated a significant amount of underreporting to the MCMIS crash file by the States, for the carriers who cooperated in the study. For the study carriers, it appears that the MCMIS file contained about 66 percent of their reportable cra...

Explaining reduction of pedestrian-motor vehicle crashes in Arkhangelsk, Russia, in 2005-2010.

Science.gov (United States)

Kudryavtsev, Alexander V; Nilssen, Odd; Lund, Johan; Grjibovski, Andrej M; Ytterstad, Børge

2012-01-01

To explain a reduction in pedestrian-motor vehicle crashes in Arkhangelsk, Russia, in 2005-2010. Retrospective ecological study. For 2005-2010, police data on pedestrian-motor vehicle crashes, traffic violations, and total motor vehicles (MVs) were combined with data on changes in national road traffic legislation and municipal road infrastructure. Negative binomial regression was used to investigate trends in monthly rates of pedestrian-motor vehicle crashes per total MVs and estimate changes in these rates per unit changes in the safety measures. During the 6 years, the police registered 2,565 pedestrian-motor vehicle crashes: 1,597 (62%) outside crosswalks, 766 (30%) on non-signalized crosswalks, and 202 (8%) on signalized crosswalks. Crash rates outside crosswalks and on signalized crosswalks decreased on average by 1.1% per month, whereas the crash rate on non-signalized crosswalks remained unchanged. Numbers of signalized and non-signalized crosswalks increased by 14 and 19%, respectively. Also, 10% of non-signalized crosswalks were combined with speed humps, and 4% with light-reflecting vertical signs. Pedestrian penalties for traffic violations increased 4-fold. Driver penalties for ignoring prohibiting signal and failure to give way to pedestrian on non-signalized crosswalk increased 7- and 8-fold, respectively. The rate of total registered drivers' traffic violations per total MVs decreased on average by 0.3% per month. All studied infrastructure and legislative measures had inverse associations with the rate of crashes outside crosswalks. The rate of crashes on signalized crosswalks showed inverse associations with related monetary penalties. The introduction of infrastructure and legislative measures is the most probable explanation of the reduction of pedestrian-motor vehicle crashes in Arkhangelsk. The overall reduction is due to decreases in rates of crashes outside crosswalks and on signalized crosswalks. No change was observed in the rate of

Compulsive cell phone use and history of motor vehicle crash.

Science.gov (United States)

O'Connor, Stephen S; Whitehill, Jennifer M; King, Kevin M; Kernic, Mary A; Boyle, Linda Ng; Bresnahan, Brian W; Mack, Christopher D; Ebel, Beth E

2013-10-01

Few studies have examined the psychological factors underlying the association between cell phone use and motor vehicle crash. We sought to examine the factor structure and convergent validity of a measure of problematic cell phone use, and to explore whether compulsive cell phone use is associated with a history of motor vehicle crash. We recruited a sample of 383 undergraduate college students to complete an online assessment that included cell phone use and driving history. We explored the dimensionality of the Cell Phone Overuse Scale (CPOS) using factor analytic methods. Ordinary least-squares regression models were used to examine associations between identified subscales and measures of impulsivity, alcohol use, and anxious relationship style, to establish convergent validity. We used negative binomial regression models to investigate associations between the CPOS and motor vehicle crash incidence. We found the CPOS to be composed of four subscales: anticipation, activity interfering, emotional reaction, and problem recognition. Each displayed significant associations with aspects of impulsivity, problematic alcohol use, and anxious relationship style characteristics. Only the anticipation subscale demonstrated statistically significant associations with reported motor vehicle crash incidence, controlling for clinical and demographic characteristics (relative ratio, 1.13; confidence interval, 1.01-1.26). For each 1-point increase on the 6-point anticipation subscale, risk for previous motor vehicle crash increased by 13%. Crash risk is strongly associated with heightened anticipation about incoming phone calls or messages. The mean score on the CPOS is associated with increased risk of motor vehicle crash but does not reach statistical significance. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Relationship of Worldwide Rocket Launch Crashes with Geophysical Parameters

Directory of Open Access Journals (Sweden)

N. Romanova

2013-01-01

Full Text Available A statistical comparison of launch crashes at different worldwide space ports with geophysical factors has been performed. A comprehensive database has been compiled, which includes 50 years of information from the beginning of the space age in 1957 about launch crashes occurring world-wide. Special attention has been paid to statistics concerning launches at the largest space ports: Plesetsk, Baikonur, Cape Canaveral, and Vandenberg. In search of a possible influence of geophysical factors on launch failures, such parameters as the vehicle type, local time, season, sunspot number, high-energy electron fluxes, and solar proton events have been examined. Also, we have analyzed correlations with the geomagnetic indices as indirect indicators of the space weather condition. Regularities found in this study suggest that further detailed studies of space weather effects on launcher systems, especially in the high-latitude regions, should be performed.

Head-on crashes on two-way interurban roads: a public health concern in road safety.

Science.gov (United States)

Olabarria, Marta; Santamariña-Rubio, Elena; Marí-Dell'Olmo, Marc; Gotsens, Mercè; Novoa, Ana M; Borrell, Carme; Pérez, Katherine

2015-09-01

To describe the magnitude and characteristics of crashes and drivers involved in head-on crashes on two-way interurban roads in Spain between 2007 and 2012, and to identify the factors associated with the likelihood of head-on crashes on these roads compared with other types of crash. A cross-sectional study was conducted using the National Crash Register. The dependent variables were head-on crashes with injury (yes/no) and drivers involved in head-on crashes (yes/no). Factors associated with head-on crashes and with being a driver involved in a head-on crash versus other types of crash were studied using a multivariate robust Poisson regression model to estimate proportion ratios (PR) and confidence intervals (95% CI). There were 9,192 head-on crashes on two-way Spanish interurban roads. A total of 15,412 men and 3,862 women drivers were involved. Compared with other types of crash, head-on collisions were more likely on roads 7 m or more wide, on road sections with curves, narrowings or drop changes, on wet or snowy surfaces, and in twilight conditions. Transgressions committed by drivers involved in head-on crashes were driving in the opposite direction and incorrectly overtaking another vehicle. Factors associated with a lower probability of head-on crashes were the existence of medians (PR=0.57; 95%CI: 0.48-0.68) and a paved shoulder of less than 1.5 meters (PR=0.81; 95%CI: 0.77-0.86) or from 1.5 to 2.45 meters (PR=0.90; 95%CI: 0.84-0.96). This study allowed the characterization of crashes and drivers involved in head-on crashes on two-way interurban roads. The lower probability observed on roads with median strips point to these measures as an effective way to reduce these collisions. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

Prevalence and factors associated with road traffic crash among taxi drivers in Hanoi, Vietnam.

Science.gov (United States)

La, Quang Ngoc; Lee, Andy H; Meuleners, Lynn B; Van Duong, Dat

2013-01-01

Injury due to road traffic crash is a major cause of ill health and premature deaths in developing countries. Taxis provide a main mode of public transport in Vietnam but there has been little research on the risk of crash for taxi drivers. This retrospective study collected information on taxi crashes for the period 2006-2009 by interviewing drivers from five taxi companies in Hanoi, Vietnam, using a structured questionnaire. Of the total 1214 participants recruited, 276 drivers reported at least one crash, giving an overall crash prevalence of 22.7%. Among the crashed group, 50 drivers (18.1%) were involved in two to four crashes. Logistic regression analysis further identified age of driver, type of driving licence, employment status, perceived sufficiency of income, seat-belt usage, and traffic infringement history to be significantly associated with the crash risk. Further prospective and qualitative studies are recommended to provide detailed crash characteristics as well as behaviour and perception of taxi drivers, so that an effective intervention can be developed to improve road safety and to prevent injury of these commercial drivers. Copyright © 2012 Elsevier Ltd. All rights reserved.

Investigation of dynamics of ELM crashes and their mitigation techniques

Energy Technology Data Exchange (ETDEWEB)

Pankin, Alexei Y. [Tech-X Corporation, Boulder, CO (United States)

2015-08-14

The accurate prediction of H-mode pedestal dynamics is critical for planning experiments in existing tokamaks and in the design of future tokamaks such as ITER and DEMO. The main objective of the proposed research is to advance the understanding of the physics of H-mode pedestal. Through advances in coupled kinetic-MHD simulations, a new model for H-mode pedestal and ELM crashes as well as an improved model for the bootstrap current will be developed. ELMmitigation techniques will also be investigated. The proposed research will help design efficient confinement scenarios and reduce transient heat loads on the divertor and plasma facing components. During the last two years, the principal investigator (PI) of this proposal actively participated in physics studies related to the DOE Joint Research Targets. These studies include the modeling of divertor heat load in the DIII-D, Alcator C-Mod, and NSTX tokamaks in 2010, and the modeling of H-mode pedestal structure in the DIII-D tokamak in 2011. It is proposed that this close collaboration with experimentalists from major US tokamaks continue during the next funding period. Verification and validation will be a strong component of the proposed research. During the course of the project, advances will be made in the following areas; Dynamics of the H-mode pedestal buildup and recovery after ELM crashes – The effects of neutral fueling, particle and thermal pinches will be explored; Dynamics of ELM crashes in realistic tokamak geometries – Heat loads associated with ELM crashes will be validated against experimental measurements. An improved model for ELM crashes will be developed; ELM mitigation – The effect of resonant magnetic perturbations on ELMs stability and their evolution will be investigated; Development of a new bootstrap current model – A reduced model for will be developed through careful verification of existing models for bootstrap current against first-principle kinetic neoclassical simulations

Is the stock market efficient?

Science.gov (United States)

Malkiel, B G

1989-03-10

A stock market is said to be efficient if it accurately reflects all relevant information in determining security prices. Critics have asserted that share prices are far too volatile to be explained by changes in objective economic events-the October 1987 crash being a case in point. Although the evidence is not unambiguous, reports of the death of the efficient market hypothesis appear premature.

Financial Services Advertising before and after the Crash of 1987.

Science.gov (United States)

Everett, Stephen E.

1988-01-01

Examines institutional changes in advertising before and after the stock market "crash" of 1987 as represented in the "Wall Street Journal." Finds that financial institutions increased the frequency and size of ads after the crash. (RS)

Taxonomy of Older Driver Behaviors and Crash Risk : Appendix C

Science.gov (United States)

2012-02-01

This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...

Load event: Aircraft crash

International Nuclear Information System (INIS)

Fritsch, H.

1985-01-01

The bibliography includes 48 quotations, up to the year 1983, on the following issues: Experiments and computational methods. Design load for the dimensioning of reinforced concrete buildings and components with respect to the dynamic load in the event of an aircraft crash. (orig./HP) [de

Initiative for safe driving and enhanced utilization of crash data

Science.gov (United States)

Wagner, John F.

1994-03-01

This initiative addresses the utilization of current technology to increase the efficiency of police officers to complete required Driving Under the Influence (DUI) forms and to enhance their ability to acquire and record crash and accident information. The project is a cooperative program among the New Mexico Alliance for Transportation Research (ATR), Science Applications International Corporation (SAIC), Los Alamos National Laboratory, and the New Mexico State Highway and Transportation Department. The approach utilizes an in-car computer and associated sensors for information acquisition and recording. Los Alamos artificial intelligence technology is leveraged to ensure ease of data entry and use.

Comparison between Euro NCAP test results and real-world crash data.

Science.gov (United States)

Kullgren, Anders; Lie, Anders; Tingvall, Claes

2010-12-01

The objective of this study was 2-fold: first, to compare Euro NCAP safety ratings of cars with those published by the Folksam real-world injury ratings; and second, to compare injury risk measures between Euro NCAP 2 and 5 Star cars with real-world injury and disability outcomes using police and insurance injury data. Car models were grouped according to the Euro NCAP star rating scores. Folksam risk of injury ratings come from statistical analysis of real-world crashes using police and insurance databases. The paired comparison method using 2-car crashes was used to control for crash speed and the mass differences between cars of different weights were normalized. For all comparisons, 5-star rated Euro NCAP cars were found to have a lower risk of injury compared to 2-star rated cars (5-star cars were 10% ± 2.5% lower risk than 2-star cars). For fatal and serious injuries, the difference was 23 ± 8 percent, and for fatal injuries alone the difference was 68 ± 32 percent. By comparison, the Folksam 5-star rated cars had a relative risk of 0.020 ± 0.0024, whereas 2-star rated car risk was 0.028 ± 0.0016, corresponding to a 27 percent difference in risk between 5- and 2-star cars. Good correlation was found between Euro NCAP test results and real-world injury outcomes. The largest difference in injury risk between 2- and 5-star rated cars in Euro NCAP was found for risk of fatality, confirming that car manufacturers have focused their safety performance on serious crash outcomes. In addition, Euro NCAP crash tests were shown to be highly correlated with serious crash performance, confirming their relevance for evaluating real-world crash performance. Good concordance was found between Euro NCAP and Folksam real-world crash and injury ratings.

Urban sprawl as a risk factor in motor vehicle crashes

Science.gov (United States)

Ewing, Reid; Hamidi, Shima; Grace, James B.

2016-01-01

A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation modelling. Controlling for covariates, we find that sprawl is associated with significantly higher direct and indirect effects on fatal crash rates. The direct effect is likely due to the higher traffic speeds in sprawling areas, and the indirect effect is due to greater vehicle miles driven in such areas. Conversely, sprawl has negative direct relationships with total crashes and non-fatal injury crashes, and these offset (and sometimes overwhelm) the positive indirect effects of sprawl on both types of crashes through the mediating effect of increased vehicle miles driven. The most likely explanation is the greater prevalence of fender benders and other minor accidents in the low speed, high conflict traffic environments of compact areas, negating the lower vehicle miles travelled per capita in such areas.

Evaluating the police service quality for handling traffic crash reporting

DEFF Research Database (Denmark)

Janstrup, Kira Hyldekær; Kaplan, Sigal; Barfod, Michael Bruhn

2017-01-01

Purpose The phenomenon of traffic crash under-reporting has been extensively documented in terms of its extent, but not equally analysed in terms of its reasons. As police distrust has been recently identified as a major reason for crash under-reporting, the purpose of this paper is to look...... at the police service quality for handling the reporting of traffic crashes. Design/methodology/approach This study introduces a novel approach to evaluate service quality that combines multi-criteria decision analysis (MCDA) with latent class analysis (LCA). Moreover, this study presents the design of a web......-based survey on the basis of the SERVQUAL approach to detecting strengths, opportunities and threats with crash reporting to the police at a strategic level. Transportation stakeholders (e.g. researchers, authorities, consultants, NGO representatives, suppliers) with an interest in traffic safety in Denmark...

Examination of factors associated in motorcycle crashes in work zones.

Science.gov (United States)

2013-01-01

This paper analyzes the factors associated with motorcycle crashes in work zones. This analysis was completed : through the collection and inspection of three types of data: 1) practices used throughout the country on this topic, : 2) crash reports a...

Changes in crash risk following re-timing of traffic signal change intervals.

Science.gov (United States)

Retting, Richard A; Chapline, Janella F; Williams, Allan F

2002-03-01

More than I million motor vehicle crashes occur annually at signalized intersections in the USA. The principal method used to prevent crashes associated with routine changes in signal indications is employment of a traffic signal change interval--a brief yellow and all-red period that follows the green indication. No universal practice exists for selecting the duration of change intervals, and little is known about the influence of the duration of the change interval on crash risk. The purpose of this study was to estimate potential crash effects of modifying the duration of traffic signal change intervals to conform with values associated with a proposed recommended practice published by the Institute of Transportation Engineers. A sample of 122 intersections was identified and randomly assigned to experimental and control groups. Of 51 eligible experimental sites, 40 (78%) needed signal timing changes. For the 3-year period following implementation of signal timing changes, there was an 8% reduction in reportable crashes at experimental sites relative to those occurring at control sites (P = 0.08). For injury crashes, a 12% reduction at experimental sites relative to those occurring at control sites was found (P = 0.03). Pedestrian and bicycle crashes at experimental sites decreased 37% (P = 0.03) relative to controls. Given these results and the relatively low cost of re-timing traffic signals, modifying the duration of traffic signal change intervals to conform with values associated with the Institute of Transportation Engineers' proposed recommended practice should be strongly considered by transportation agencies to reduce the frequency of urban motor vehicle crashes.

In pedestrian crashes, it's vehicle speed that matters the most

Science.gov (United States)

2000-05-13

A recently prepared report on pedestrian injuries provides these two main findings: 1) regardless of age, pedestrians involved in crashes are more likely to be killed as vehicle speeds increase; and 2) in crashes at any speed, older pedestrians are m...

Type, size and age of vehicles driven by teenage drivers killed in crashes during 2008-2012.

Science.gov (United States)

McCartt, Anne T; Teoh, Eric R

2015-04-01

Given teenagers' elevated crash rates, it is especially important that their vehicles have key safety features and good crash protection. A profile of vehicles driven by teenagers killed in crashes was developed. Data on vehicles of drivers ages 15-17 and ages 35-50 who died in crashes during 2008-2012 were obtained from the Fatality Analysis Reporting System. Using vehicle identification numbers, the vehicle make, model and model year were identified. 29% of fatally injured teenagers were driving mini or small cars, 82% were driving vehicles at least 6 years old, and 48% were driving vehicles at least 11 years old. Compared with middle-aged drivers, teenagers' vehicles more often were small or mini cars or older vehicles. Few teenagers' vehicles had electronic stability control or side airbags as standard features. Parents should consider safety when choosing vehicles for their teenagers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

National Motor Vehicle Crash Causation Survey (NMVCCS) - NMVCCS XML Case Viewer

Data.gov (United States)

Department of Transportation — The National Motor Vehicle Crash Causation Survey (NMVVCS) was a nationwide survey of crashes involving light passenger vehicles, with a focus on the factors related...

A hot spot analysis of teenage crashes : an assessment of crashes in Houston, Texas.

Science.gov (United States)

2014-09-01

Today, states have enacted laws to ensure that teen drivers are more skilled and drive safely. The result is : fewer accidents. However, in previous research, when teen crashes were mapped, certain streets and areas : appeared to have more accidents ...

Influence of horizontally curved roadway section characteristics on motorcycle-to-barrier crash frequency.

Science.gov (United States)

Gabauer, Douglas J; Li, Xiaolong

2015-04-01

The purpose of this study was to investigate motorcycle-to-barrier crash frequency on horizontally curved roadway sections in Washington State using police-reported crash data linked with roadway data and augmented with barrier presence information. Data included 4915 horizontal curved roadway sections with 252 of these sections experiencing 329 motorcycle-to-barrier crashes between 2002 and 2011. Negative binomial regression was used to predict motorcycle-to-barrier crash frequency using horizontal curvature and other roadway characteristics. Based on the model results, the strongest predictor of crash frequency was found to be curve radius. This supports a motorcycle-to-barrier crash countermeasure placement criterion based, at the very least, on horizontal curve radius. With respect to the existing horizontal curve criterion of 820 feet or less, curves meeting this criterion were found to increase motorcycle-to-barrier crash frequency rate by a factor of 10 compared to curves not meeting this criterion. Other statistically significant predictors were curve length, traffic volume and the location of adjacent curves. Assuming curves of identical radius, the model results suggest that longer curves, those with higher traffic volume, and those that have no adjacent curved sections within 300 feet of either curve end would likely be better candidates for a motorcycle-to-barrier crash countermeasure. Copyright © 2015 Elsevier Ltd. All rights reserved.

COMPARISON OF SEVERITY AFFECTING FACTORS BETWEEN YOUNG AND OLDER DRIVERS INVOLVED IN SINGLE VEHICLE CRASHES

Directory of Open Access Journals (Sweden)

Sunanda DISSANAYAKE, Ph.D., P.E.

2004-01-01

Full Text Available Single vehicle crashes contribute to a significant amount of fatalities in the United States. At the same time, fatality crash involvement rates of young and older drivers are well above the average and both groups are identified as critical groups when it comes to highway safety. Therefore, the study described in this paper developed separate models to predict crash severity of single vehicle crashes by young and older drivers. By using the models, factors affecting towards increased crash severity were identified for each group and comparisons were made. Almost all the common identified factors influenced both driver groups in the same manner except in the case of alcohol and drug usage, which indicated an interesting finding in the case of crash severity of older drivers. Speeding and non-usage of a restraint device were the two most important factors affecting towards increased crash severity for both driver groups at all severity levels. Additionally, ejection and existence of curve/grade were determinants of higher young driver crash severity at all levels. For older drivers, having a frontal impact point was a severity determinant at all levels. County of residence and weather condition were not effective in making any changes with respect to crash severity at any level, while some other factors had a minimal affect. Findings of this study are beneficial in investigating the potential ways of reducing crash severity, which could also be influential in reducing the occurrence of crashes as well.

Population based case–control study of serious non-fatal motorcycle crashes

Science.gov (United States)

2013-01-01

Background Motorcycle sales, registration and use are increasing in many countries. The epidemiological literature on risk factors for motorcycle injury is becoming outdated, due to changes in rider demography, licensing regulations, traffic mix and density, road environments, and motorcycle designs and technologies. Further, the potential contribution of road infrastructure and travel speed has not yet been examined. Methods/design A population based case–control study together with a nested case-crossover study is planned. Cases will be motorcycle riders who are injured but not killed in a motorcycle crash on a public road within 150 km radius of Melbourne, Australia, and admitted to one of the study hospitals. Controls will be motorcycle riders who ride through the crash site on the same type of day (weekday or weekend) within an hour of the crash time. Data on rider, bike, and trip characteristics will be collected from the participants by questionnaire. Data on crash site characteristics will be collected in a structured site inspection, and travel speed for the cases will be estimated from these data. Travel speed for the controls will be measured prior to recruitment with a radar traffic detection device as they ride through the crash site. Control sites for the case-crossover study will be selected 1 km upstream from the crash site and matched on either intersection status or road curvature (either straight or cornered). If the initial site selected does not match the case site on these characteristics, then the closest matching site on the case route will be selected. Conditional multivariate logistic regression models will be used to compare risk between the matched case and control riders and to examine associations between road infrastructure and road environment characteristics and crash occurrence. Interactions between type of site and speed will be tested to determine if site type is an effect modifier of the relationship between speed and crash

Finite pressure effects on the tokamak sawtooth crash

International Nuclear Information System (INIS)

Nishimura, Yasutaro

1998-07-01

The sawtooth crash is a hazardous, disruptive phenomenon that is observed in tokamaks whenever the safety factor at the magnetic axis is below unity. Recently, Tokamak Test Fusion Reactor (TFTR) experimental data has revealed interesting features of the dynamical pressure evolution during the crash phase. Motivated by the experimental results, this dissertation focuses on theoretical modeling of the finite pressure effects on the nonlinear stage of the sawtooth crash. The crash phase has been studied numerically employed a toroidal magnetohydrodynamic (MHD) initial value code deduced from the FAR code. For the first time, by starting from a concentric equilibrium, it has been shown that the evolution through an m/n = 1/1 magnetic island induces secondary high-n ballooning instabilities. The magnetic island evolution gives rise to convection of the pressure inside the inversion radius and builds up a steep pressure gradient across the island separatrix, or current sheet, and thereby triggers ballooning instabilities below the threshold for the axisymmetric equilibrium. Due to the onset of secondary ballooning modes, concomitant fine scale vortices and magnetic stochasticity are generated. These effects produce strong flows across the current sheet, and thereby significant modify the m = 1 driven magnetic reconnection process. The resultant interaction of the high-n ballooning modes with the magnetic reconnection process is discussed

STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS*

Science.gov (United States)

HUDOMIET, PÉTER; KÉZDI, GÁBOR; WILLIS, ROBERT J.

2011-01-01

SUMMARY This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households’ expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market. PMID:21547244

STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS.

Science.gov (United States)

Hudomiet, Péter; Kézdi, Gábor; Willis, Robert J

2011-01-01

This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households' expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market.

Two-fractal overlap time series: Earthquakes and market crashes

Indian Academy of Sciences (India)

velocity over the other and time series of stock prices. An anticipation method for some of the crashes have been proposed here, based on these observations. Keywords. Cantor set; time series; earthquake; market crash. PACS Nos 05.00; 02.50.-r; 64.60; 89.65.Gh; 95.75.Wx. 1. Introduction. Capturing dynamical patterns of ...

Crash protectiveness to occupant injury and vehicle damage: An investigation on major car brands.

Science.gov (United States)

Huang, Helai; Li, Chunyang; Zeng, Qiang

2016-01-01

This study sets out to investigate vehicles' crash protectiveness on occupant injury and vehicle damage, which can be deemed as an extension of the traditional crash worthiness. A Bayesian bivariate hierarchical ordered logistic (BVHOL) model is developed to estimate the occupant protectiveness (OP) and vehicle protectiveness (VP) of 23 major car brands in Florida, with considering vehicles' crash aggressivity and controlling external factors. The proposed model not only takes over the strength of the existing hierarchical ordered logistic (HOL) model, i.e. specifying the order characteristics of crash outcomes and cross-crash heterogeneities, but also accounts for the correlation between the two crash responses, driver injury and vehicle damage. A total of 7335 two-vehicle-crash records with 14,670 cars involved in Florida are used for the investigation. From the estimation results, it's found that most of the luxury cars such as Cadillac, Volvo and Lexus possess excellent OP and VP while some brands such as KIA and Saturn perform very badly in both aspects. The ranks of the estimated safety performance indices are even compared to the counterparts in Huang et al. study [Huang, H., Hu, S., Abdel-Aty, M., 2014. Indexing crash worthiness and crash aggressivity by major car brands. Safety Science 62, 339-347]. The results show that the rank of occupant protectiveness index (OPI) is relatively coherent with that of crash worthiness index, but the ranks of crash aggressivity index in both studies is more different from each other. Meanwhile, a great discrepancy between the OPI rank and that of vehicle protectiveness index is found. What's more, the results of control variables and hyper-parameters estimation as well as comparison to HOL models with separate or identical threshold errors, demonstrate the validity and advancement of the proposed model and the robustness of the estimated OP and VP. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transferability and robustness of real-time freeway crash risk assessment.

Science.gov (United States)

Shew, Cameron; Pande, Anurag; Nuworsoo, Cornelius

2013-09-01

This study examines the data from single loop detectors on northbound (NB) US-101 in San Jose, California to estimate real-time crash risk assessment models. The classification tree and neural network based crash risk assessment models developed with data from NB US-101 are applied to data from the same freeway, as well as to the data from nearby segments of the SB US-101, NB I-880, and SB I-880 corridors. The performance of crash risk assessment models on these nearby segments is the focus of this research. The model applications show that it is in fact possible to use the same model for multiple freeways, as the underlying relationships between traffic data and crash risk remain similar. The framework provided here may be helpful to authorities for freeway segments with newly installed traffic surveillance apparatuses, since the real-time crash risk assessment models from nearby freeways with existing infrastructure would be able to provide a reasonable estimate of crash risk. The robustness of the model output is also assessed by location, time of day, and day of week. The analysis shows that on some locations the models may require further learning due to higher than expected false positive (e.g., the I-680/I-280 interchange on US-101 NB) or false negative rates. The approach for post-processing the results from the model provides ideas to refine the model prior to or during the implementation. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.

Motorcycle crash-related emergency department visits and hospitalizations for traumatic brain injury in North Carolina.

Science.gov (United States)

Harmon, Katherine J; Marshall, Stephen W; Proescholdbell, Scott K; Naumann, Rebecca B; Waller, Anna E

2015-01-01

To examine statewide emergency department (ED) visit data for motorcycle crash morbidity and healthcare utilization due to traumatic brain injuries (TBIs) and non-TBIs. North Carolina ED data (2010-2012) and hospital discharge data (2009-2011). Statewide ED visits and hospitalizations due to injuries from traffic-related motorcycle crashes stratified by TBI status. Descriptive study. Descriptive statistics include age, sex, mode of transport, disposition, expected source of payment, hospital length of stay, and hospital charges. Over the study period, there were 18 780 ED visits and 3737 hospitalizations due to motorcycle crashes. Twelve percent of ED visits for motorcycle crashes and 26% of hospitalizations for motorcycle crashes had a diagnosis of TBI. Motorcycle crash-related hospitalizations with a TBI diagnosis had median hospital charges that were nearly $9000 greater than hospitalizations without a TBI diagnosis. Emergency department visits and hospitalizations due to motorcycle crashes with a TBI diagnosis consumed more healthcare resources than motorcycle crash-related ED visits and hospitalizations without a TBI diagnosis. Increased awareness of motorcyclists by other road users and increased use of motorcycle helmets are 2 strategies to mitigate the incidence and severity of motorcycle crash injuries, including TBIs.

Human fatigue and the crash of the airship Italia

Directory of Open Access Journals (Sweden)

Gregg A. Bendrick

2016-07-01

Full Text Available The airship Italia, commanded by General Umberto Nobile, crashed during its return flight from the North Pole in 1928. The cause of the accident was never satisfactorily explained. We present evidence that the crash may have been fatigue-related. Nobile's memoirs indicate that at the time of the crash he had been awake for at least 72 h. Sleep deprivation impairs multiple aspects of cognitive functioning necessary for exploration missions. Just prior to the crash, Nobile made three command errors, all of which are of types associated with inadequate sleep. First, he ordered a release of lift gas when he should have restarted engines (an example of incorrect data synthesis, with deterioration of divergent thinking; second, he inappropriately ordered the ship above the cloud layer (a deficiency in the assessment of relative risks; and third, he remained above the cloud layer for a prolonged period of time (examples of attention to secondary problems, and calculation problems. We argue that as a result of these three errors, which would not be expected from such an experienced commander, there was no longer enough static lift to maintain level flight when the ship went below the cloud layer. Applying Circadian Performance Simulation Software to the sleep–wake patterns described by Nobile in his memoirs, we found that the predicted performance for someone awake as long as he had been is extremely low. This supports the historical evidence that human fatigue contributed to the crash of the Italia.

Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach

DEFF Research Database (Denmark)

Kaplan, Sigal; Prato, Carlo Giacomo

2012-01-01

from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. Methods: The analysis is conducted by means of a mixed...... about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing a forgiving infrastructure within a sustainable safety systems......Objective: The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives...

Alcohol and older drivers' crashes.

Science.gov (United States)

2014-09-01

Researchers have examined the effects of alcohol consumption : on older adults functioning, and some have : addressed alcohols effects on older drivers crash risk. : Generally, the findings have shown that alcohol is less : likely to be a fa...

Crash-related mortality and model year: are newer vehicles safer?

Science.gov (United States)

Ryb, Gabriel E; Dischinger, Patricia C; McGwin, Gerald; Griffin, Russell L

2011-01-01

The objective of this study was to determine whether occupants of newer vehicles experience a lower risk of crash-related mortality. The occurrence of death was studied in relation to vehicle model year (MY) among front seat vehicular occupants, age ≥ 16 captured in the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) between 2000 and 2008. The associations between death and other occupant, vehicular and crash characteristics were also explored. Multiple logistic regression models for the prediction of death were built with model year as the independent variable and other characteristics linked to death as covariates. Imputation was used for missing data; weighted data was used. A total of 70,314 cases representing 30,514,372 weighted cases were available for analysis. Death occurred in 0.6% of the weighted population. Death was linked to age>60, male gender, higher BMI, near lateral direction of impact, high delta v, rollover, ejection and vehicle mismatch, and negatively associated with seatbelt use and rear and far lateral direction of impact. Mortality decreased with later model year groups (MY<94 0.78%, MY 94-97 0.53%, MY 98-04 0.51% and MY 05-08 0.38%, p=<0.0001). After adjustment for confounders, MY 94-97, MY 98-04 and MY 05-08 showed decreased odds of death [OR 0.80 (0.69-0.94), 0.82 (0.70-0.97), and 0.67 (0.47-0.96), respectively] when compared to MY <94. Newer vehicles are associated with lower crash-related mortality. Their introduction into the vehicle fleet may explain, at least in part, the decrease in mortality rates in the past two decades.

The Crash Intensity Evaluation Using General Centrality Criterions and a Geographically Weighted Regression

Science.gov (United States)

Ghadiriyan Arani, M.; Pahlavani, P.; Effati, M.; Noori Alamooti, F.

2017-09-01

Today, one of the social problems influencing on the lives of many people is the road traffic crashes especially the highway ones. In this regard, this paper focuses on highway of capital and the most populous city in the U.S. state of Georgia and the ninth largest metropolitan area in the United States namely Atlanta. Geographically weighted regression and general centrality criteria are the aspects of traffic used for this article. In the first step, in order to estimate of crash intensity, it is needed to extract the dual graph from the status of streets and highways to use general centrality criteria. With the help of the graph produced, the criteria are: Degree, Pageranks, Random walk, Eccentricity, Closeness, Betweenness, Clustering coefficient, Eigenvector, and Straightness. The intensity of crash point is counted for every highway by dividing the number of crashes in that highway to the total number of crashes. Intensity of crash point is calculated for each highway. Then, criteria and crash point were normalized and the correlation between them was calculated to determine the criteria that are not dependent on each other. The proposed hybrid approach is a good way to regression issues because these effective measures result to a more desirable output. R2 values for geographically weighted regression using the Gaussian kernel was 0.539 and also 0.684 was obtained using a triple-core cube. The results showed that the triple-core cube kernel is better for modeling the crash intensity.

Improving freight crash incident management.

Science.gov (United States)

2015-06-01

The objective of this study was to determine the most effective way to mitigate the effect of freight : crash incidents on Louisiana freeways. Candidate incident management strategies were reviewed from : practice in other states and from those publi...

Crash course in readers' advisory

CERN Document Server

Orr, Cynthia

2014-01-01

One of the key services librarians provide is helping readers find books they'll enjoy. This ""crash course"" will furnish you with the basic, practical information you need to excel at readers' advisory (RA) for adults and teens.

A dynamic mathematical test of international property securities bubbles and crashes

Science.gov (United States)

Hui, Eddie C. M.; Zheng, Xian; Wang, Hui

2010-04-01

This study investigates property securities bubbles and crashes by using a dynamic mathematical methodology developed from the previous research (Watanabe et al. 2007a, b [31,32]). The improved model is used to detect the bubble and crash periods in five international countries/cities (namely, United States, United Kingdom, Japan, Hong Kong and Singapore) from Jan, 2000 to Oct, 2008. By this model definition, we are able to detect the beginning of each bubble period even before it bursts. Meanwhile, the empirical results show that most of property securities markets experienced bubble periods between 2003 and 2007, and crashes happened in Apr 2008 triggered by the Subprime Mortgage Crisis of US. In contrast, Japan suffered the shortest bubble period and no evidence has documented the existence of crash there.

The shift to and from daylight savings time and motor vehicle crashes.

Science.gov (United States)

Lambe, M; Cummings, P

2000-07-01

The objective of the study was to examine whether the shifts to and from daylight savings time in Sweden have short-term effects on the incidence of traffic crashes. A database maintained by the Swedish National Road Administration was used to examine crashes from 1984 through 1995, that occurred on state roads the Monday preceding, the Monday immediately after (index Monday), and the Monday 1 week after the change to daylight savings time in the spring and for the corresponding three Mondays in the autumn. The Mondays 1 week before and after the time changes were taken as representing the expected incidence of crashes. Crash incidence was calculated per 1000 person-years using population estimates for each year of the study. The association between 1 h of possible sleep loss and crash incidence was estimated by the incidence rate ratio from negative binomial regression. The incidence rate ratio was 1.04 (95% CI, 0.92-1.16) for a Monday on which drivers were expected to have had 1 h less sleep, compared with other Mondays. In the spring, the incidence rate ratio for crashes was 1.11 (95% CI, 0.93-1.31) for Mondays after the time change compared to other spring Mondays. The corresponding rate ratio for the fall was 0.98 (95% CI, 0.84-1.15) It was concluded that the shift to and from daylight savings time did not have measurable important immediate effects on crash incidence in Sweden.

A Partial Proportional Odds Model for Pedestrian Crashes at Mid-Blocks in Melbourne Metropolitan Area

Directory of Open Access Journals (Sweden)

Toran Pour Alireza

2016-01-01

Full Text Available Pedestrian crashes account for 11% of all reported traffic crashes in Melbourne metropolitan area between 2004 and 2013. There are very limited studies on pedestrian accidents at mid-blocks. Mid-block crashes account for about 46% of the total pedestrian crashes in Melbourne metropolitan area. Meanwhile, about 50% of all pedestrian fatalities occur at mid-blocks. In this research, Partial Proportional Odds (PPO model is applied to examine vehicle-pedestrian crash severity at mid-blocks in Melbourne metropolitan area. The PPO model is a logistic regression model that allows the covariates that meet the proportional odds assumption to affect different crash severity levels with the same magnitude; whereas the covariates that do not meet the proportional odds assumption can have different effects on different severity levels. In this research vehicle-pedestrian crashes at mid-blocks are analysed for first time. In addition, some factors such as distance of crashes to public transport stops, average road slope and some social characteristics are considered to develop the model in this research for first time. Results of PPO model show that speed limit, light condition, pedestrian age and gender, and vehicle type are the most significant factors that influence vehicle-pedestrian crash severity at mid-blocks.

Overreaction or Fundamentals: Some Lessons from Insiders' Response to the Market Crash of 1987.

OpenAIRE

Seyhun, H Nejat

1990-01-01

This paper shows that the 1987 crash was a surprise to corporate insiders; insiders became buyers of stock in record numbers immediately following the crash; stocks that declined more during the crash were also purchased more by insiders; and stocks that were purchased more extensively by insiders during October 1987 showed larger positive returns in 1988. The overall evidence suggests that overreaction was an important part of the crash. Copyright 1990 by American Finance Association.

Assessing crash risk considering vehicle interactions with trucks using point detector data.

Science.gov (United States)

Hyun, Kyung Kate; Jeong, Kyungsoo; Tok, Andre; Ritchie, Stephen G

2018-03-12

Trucks have distinct driving characteristics in general traffic streams such as lower speeds and limitations in acceleration and deceleration. As a consequence, vehicles keep longer headways or frequently change lane when they follow a truck, which is expected to increase crash risk. This study introduces several traffic measures at the individual vehicle level to capture vehicle interactions between trucks and non-trucks and analyzed how the measures affect crash risk under different traffic conditions. The traffic measures were developed using headways obtained from Inductive Loop Detectors (ILDs). In addition, a truck detection algorithm using a Gaussian Mixture (GM) model was developed to identify trucks and to estimate truck exposure from ILD data. Using the identified vehicle types from the GM model, vehicle interaction metrics were categorized into three groups based on the combination of leading and following vehicle types. The effects of the proposed traffic measures on crash risk were modeled in two different cases of prior- and non-crash using a case-control approach utilizing a conditional logistic regression. Results showed that the vehicle interactions between the leading and following vehicle types were highly associated with crash risk, and further showed different impacts on crash risk by traffic conditions. Specifically, crashes were more likely to occur when a truck following a non-truck had shorter average headway but greater headway variance in heavy traffic while a non-truck following a truck had greater headway variance in light traffic. This study obtained meaningful conclusions that vehicle interactions involved with trucks were significantly related to the crash likelihood rather than the measures that estimate average traffic condition such as total volume or average headway of the traffic stream. Copyright © 2018 Elsevier Ltd. All rights reserved.

Using event-triggered naturalistic data to examine the prevalence of teen driver distractions in rear-end crashes.

Science.gov (United States)

Carney, Cher; Harland, Karisa K; McGehee, Daniel V

2016-06-01

While teen driver distraction is cited as a leading cause of crashes, especially rear-end crashes, little information is available regarding its true prevalence. The majority of distraction studies rely on data derived from police reports, which provide limited information regarding driver distraction. This study examined over 400 teen driver rear-end crashes captured by in-vehicle event recorders. A secondary data analysis was conducted, paying specific attention to driver behaviors, eyes-off-road time, and response times to lead-vehicle braking. Among teens in moderate to severe rear-end crashes, over 75% of drivers were observed engaging in a potentially distracting behavior. The most frequently seen driver behaviors were cell phone use, attending to a location outside the vehicle, and attending to passengers. Drivers using a cell phone had a significantly longer response time than drivers not engaged in any behaviors, while those attending to passengers did not. Additionally, in about 50% of the rear-end crashes where the driver was operating/looking at a phone (e.g., texting), the driver showed no driver response (i.e., braking or steering input) before impact, compared to 10% of crashes where the driver was attending to a passenger. The high frequency of attending to passengers and use of a cell phone leading up to a crash, compounded with the associated risks, underlines the importance of continued investigation in these areas. Parents and teens must be educated regarding the frequency of and the potential effects of distractions. Additional enforcement may be necessary if Graduated Driver Licensing (GDL) programs are to be effective. Systems that alert distracted teens could also be especially helpful in reducing rear-end collisions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.

Characteristics of single-vehicle crashes with e-bikes in Switzerland.

Science.gov (United States)

Hertach, Patrizia; Uhr, Andrea; Niemann, Steffen; Cavegn, Mario

2018-08-01

In Switzerland, the usage and accident numbers of e-bikes have strongly increased in recent years. According to official statistics, single-vehicle accidents constitute an important crash type. Up to date, very little is known about the mechanisms and causes of these crashes. To gain more insight, a survey was conducted among 3658 e-cyclists in 2016. The crash risk and injury severity were analysed using logistic regression models. 638 (17%) e-cyclists had experienced a single-vehicle accident in road traffic since the beginning of their e-bike use. Risk factors were high riding exposure, male sex, and using the e-bike mainly for the purpose of getting to work or school. There was no effect of age on the crash risk. Skidding, falling while crossing a threshold, getting into or skidding on a tram/railway track and evasive actions were the most important accident mechanisms. The crash causes mentioned most often were a slippery road surface, riding too fast for the situation and inability to keep the balance. Women, elderly people, riders of e-bikes with a pedal support up to 45 km/h and e-cyclists who considered themselves to be less fit in comparison to people of the same age had an increased risk of injury. This study confirms the high relevance of single-vehicle crashes with e-bikes. Measures to prevent this type of accident could include the sensitisation of e-cyclists regarding the most common accident mechanisms and causes, a regular maintenance of bicycle pathways, improvements regarding tram and railway tracks and technological advancements of e-bikes. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Exploring older driver crash trend: New Jersey case study

Directory of Open Access Journals (Sweden)

Vanvi Trieu

2014-04-01

Full Text Available Older drivers age 65 and above are known to experience greater risk on the roadway as well as increasing the risk to other roadway users. Within the next 20 years, their population is expected to increase from 41 million in 2011 to 70 million in 2030. To address this foreseeable change, the nation's recent Moving Ahead for Progress in the 21st Century (MAP-21 act requires state and local governments to examine older drivers and pedestrian risks and implement countermeasures as appropriate. This research was conducted to assist agencies in strategising for future plans, programmes and initiatives to better address the problem presented. This was accomplished by performing a detailed engineering analysis on crash data of older drivers over a 10-year period (2003–2012 from the state of New Jersey to identify crash trends and characteristics. A major finding from this research was the increase in fatal crashes of older drivers as a function of age. Top-ranking collision types with other vehicles and non-vehicles were identified. Crashes as a function of seasonal change, climate and lighting conditions were also examined.

Sleep deficiency and motor vehicle crash risk in the general population: a prospective cohort study.

Science.gov (United States)

Gottlieb, Daniel J; Ellenbogen, Jeffrey M; Bianchi, Matt T; Czeisler, Charles A

2018-03-20

Insufficient sleep duration and obstructive sleep apnea, two common causes of sleep deficiency in adults, can result in excessive sleepiness, a well-recognized cause of motor vehicle crashes, although their contribution to crash risk in the general population remains uncertain. The objective of this study was to evaluate the relation of sleep apnea, sleep duration, and excessive sleepiness to crash risk in a community-dwelling population. This was a prospective observational cohort study nested within the Sleep Heart Health Study, a community-based study of the health consequences of sleep apnea. The participants were 1745 men and 1456 women aged 40-89 years. Sleep apnea was measured by home polysomnography and questionnaires were used to assess usual sleep duration and daytime sleepiness. A follow-up questionnaire 2 years after baseline ascertained driving habits and motor vehicle crash history. Logistic regression analysis was used to examine the relation of sleep apnea and sleep duration at baseline to the occurrence of motor vehicle crashes during the year preceding the follow-up visit, adjusting for relevant covariates. The population-attributable fraction of motor vehicle crashes was estimated from the sample proportion of motor vehicle crashes and the adjusted odds ratios for motor vehicle crash within each exposure category. Among 3201 evaluable participants, 222 (6.9%) reported at least one motor vehicle crash during the prior year. A higher apnea-hypopnea index (p vehicle crashes was 10% due to sleep apnea and 9% due to sleep duration less than 7 hours. Sleep deficiency due to either sleep apnea or insufficient sleep duration is strongly associated with motor vehicle crashes in the general population, independent of self-reported excessive sleepiness.

Effects from airplane crashes and gas explosions to Leningrad nuclear plant

International Nuclear Information System (INIS)

Junttila, K.; Varpasuo, P.

1998-01-01

In this study the effects of aircraft crash and gas explosion to Leningrad Nuclear Power Plant has been researched. One of the two reactor buildings is modeled with finite element method using the pre-processor program MSC/PATRAN and analyzed with MSC/NASTRAN analysis program. In MSC/PATRAN or FEMAP, which is a pre-processor program of MSC/NASTRAN for Windows, the reactor building of the plant has been modeled with shell and beam elements and the load sets describing the aircraft crash and gas explosion have been developed. The crash loads are from Cessna 210 civil airplane crash with impact velocity 360 km/h and maximum impact force of 7 MN and Phantom RF-43 military airplane crash with impact velocity 215 m/s and with maximum impact force of 110 MN. The gas explosion pressure wave simulates the deflagration wave with maximum pressure of 0,045 MPa. Seven Cessna 210 airplane crash locations, two Phantom RF-43 airplane crash locations and one gas explosion load case is modeled. Airplane crash loads were from different directions and to different points of impact in the reactor building. The gas explosion load was assumed to affect the reactor building from one side parallel to one of the global coordinate axes of the model. With MSC/NASTRAN reactions from loads are analyzed. All loads were timedependent; their magnitude varied with time and consequently the analysis was carried out with the aid of transient response analysis. Time step in Cessna 210 analysis was 0,003 s and in Phantom RF-43 and gas explosion analyses 0,01 s. The greatest displacement from Cessna 210 loads was 12 mm and from Phantom RF-43 load 344 mm. The last value shows that construction would fail with that load. The greatest displacement from gas explosion load was 68 mm. Stresses are not so interesting in this preliminary analysis of the effects, but they are shown in pictures embedded in the report text. Displacements were greatest in upper part of the reactor building, where no intersections

Explaining reduction of pedestrian–motor vehicle crashes in Arkhangelsk, Russia, in 2005–2010

Directory of Open Access Journals (Sweden)

Alexander V. Kudryavtsev

2012-09-01

Full Text Available Objective. To explain a reduction in pedestrian–motor vehicle crashes in Arkhangelsk, Russia, in 2005–2010. Study design. Retrospective ecological study. Methods. For 2005–2010, police data on pedestrian–motor vehicle crashes, traffic violations, and total motor vehicles (MVs were combined with data on changes in national road traffic legislation and municipal road infrastructure. Negative binomial regression was used to investigate trends in monthly rates of pedestrian–motor vehicle crashes per total MVs and estimate changes in these rates per unit changes in the safety measures. Results. During the 6 years, the police registered 2,565 pedestrian–motor vehicle crashes: 1,597 (62% outside crosswalks, 766 (30% on non-signalized crosswalks, and 202 (8% on signalized crosswalks. Crash rates outside crosswalks and on signalized crosswalks decreased on average by 1.1% per month, whereas the crash rate on non-signalized crosswalks remained unchanged. Numbers of signalized and non-signalized crosswalks increased by 14 and 19%, respectively. Also, 10% of non-signalized crosswalks were combined with speed humps, and 4% with light-reflecting vertical signs. Pedestrian penalties for traffic violations increased 4-fold. Driver penalties for ignoring prohibiting signal and failure to give way to pedestrian on non-signalized crosswalk increased 7- and 8-fold, respectively. The rate of total registered drivers’ traffic violations per total MVs decreased on average by 0.3% per month. All studied infrastructure and legislative measures had inverse associations with the rate of crashes outside crosswalks. The rate of crashes on signalized crosswalks showed inverse associations with related monetary penalties. Conclusions. The introduction of infrastructure and legislative measures is the most probable explanation of the reduction of pedestrian–motor vehicle crashes in Arkhangelsk. The overall reduction is due to decreases in rates of crashes

Application of a random effects negative binomial model to examine tram-involved crash frequency on route sections in Melbourne, Australia.

Science.gov (United States)

Naznin, Farhana; Currie, Graham; Logan, David; Sarvi, Majid

2016-07-01

Safety is a key concern in the design, operation and development of light rail systems including trams or streetcars as they impose crash risks on road users in terms of crash frequency and severity. The aim of this study is to identify key traffic, transit and route factors that influence tram-involved crash frequencies along tram route sections in Melbourne. A random effects negative binomial (RENB) regression model was developed to analyze crash frequency data obtained from Yarra Trams, the tram operator in Melbourne. The RENB modelling approach can account for spatial and temporal variations within observation groups in panel count data structures by assuming that group specific effects are randomly distributed across locations. The results identify many significant factors effecting tram-involved crash frequency including tram service frequency (2.71), tram stop spacing (-0.42), tram route section length (0.31), tram signal priority (-0.25), general traffic volume (0.18), tram lane priority (-0.15) and ratio of platform tram stops (-0.09). Findings provide useful insights on route section level tram-involved crashes in an urban tram or streetcar operating environment. The method described represents a useful planning tool for transit agencies hoping to improve safety performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Patient distribution in a mass casualty event of an airplane crash.

Science.gov (United States)

Postma, Ingri L E; Weel, Hanneke; Heetveld, Martin J; van der Zande, Ineke; Bijlsma, Taco S; Bloemers, Frank W; Goslings, J Carel

2013-11-01

Difficulties have been reported in the patient distribution during Mass Casualty Incidents. In this study we analysed the regional patient distribution protocol (PDP) and the actual patient distribution after the 2009 Turkish Airlines crash near Amsterdam. Analysis of the patient distribution of 126 surviving casualties of the crash by collecting data on medical treatment capacity, number of patients received per hospital, triage classification, Injury Severity Score (ISS), secondary transfers, distance from the crash site, and the critical mortality rate. The PDP holds ambiguous definitions of medical treatment capacity and was not followed. There were 14 receiving hospitals (distance from crash: 5.8-53.5 km); four hospitals received 133-213% of their treatment capacity, and 5 hospitals received 1 patient. Three hospitals within 20 km of the crash did not receive any casualties. Level I trauma centres received 89% of the 'critical' casualties and 92% of the casualties with ISS ≥ 16. Only 3 casualties were secondarily transferred, and no casualties died in, or on the way to hospital (critical mortality rate=0%). Patient distribution worked out well after the crash as secondary transfers were low and critical mortality rate was zero. However, the regional PDP was not followed in this MCI and casualties were unevenly distributed among hospitals. The PDP is indistinctive, and should be updated in cooperation between Emergency Services, surrounding hospitals, and Schiphol International Airport as a high risk area. Copyright © 2013 Elsevier Ltd. All rights reserved.

Investigation of time and weather effects on crash types using full Bayesian multivariate Poisson lognormal models.

Science.gov (United States)

El-Basyouny, Karim; Barua, Sudip; Islam, Md Tazul

2014-12-01

Previous research shows that various weather elements have significant effects on crash occurrence and risk; however, little is known about how these elements affect different crash types. Consequently, this study investigates the impact of weather elements and sudden extreme snow or rain weather changes on crash type. Multivariate models were used for seven crash types using five years of daily weather and crash data collected for the entire City of Edmonton. In addition, the yearly trend and random variation of parameters across the years were analyzed by using four different modeling formulations. The proposed models were estimated in a full Bayesian context via Markov Chain Monte Carlo simulation. The multivariate Poisson lognormal model with yearly varying coefficients provided the best fit for the data according to Deviance Information Criteria. Overall, results showed that temperature and snowfall were statistically significant with intuitive signs (crashes decrease with increasing temperature; crashes increase as snowfall intensity increases) for all crash types, while rainfall was mostly insignificant. Previous snow showed mixed results, being statistically significant and positively related to certain crash types, while negatively related or insignificant in other cases. Maximum wind gust speed was found mostly insignificant with a few exceptions that were positively related to crash type. Major snow or rain events following a dry weather condition were highly significant and positively related to three crash types: Follow-Too-Close, Stop-Sign-Violation, and Ran-Off-Road crashes. The day-of-the-week dummy variables were statistically significant, indicating a possible weekly variation in exposure. Transportation authorities might use the above results to improve road safety by providing drivers with information regarding the risk of certain crash types for a particular weather condition. Copyright © 2014 Elsevier Ltd. All rights reserved.

Societal costs of traffic crashes and crime in Michigan : 2011 update.

Science.gov (United States)

2011-06-01

"Cost estimates, including both monetary and nonmonetary quality-of-life costs specific to Michigan, were : estimated for overall traffic crashes and index crimes by experts in the field of economics of traffic crashes : and crimes. These cost estima...

A spatial generalized ordered response model to examine highway crash injury severity.

Science.gov (United States)

Castro, Marisol; Paleti, Rajesh; Bhat, Chandra R

2013-03-01

This paper proposes a flexible econometric structure for injury severity analysis at the level of individual crashes that recognizes the ordinal nature of injury severity categories, allows unobserved heterogeneity in the effects of contributing factors, as well as accommodates spatial dependencies in the injury severity levels experienced in crashes that occur close to one another in space. The modeling framework is applied to analyze the injury severity sustained in crashes occurring on highway road segments in Austin, Texas. The sample is drawn from the Texas Department of Transportation (TxDOT) crash incident files from 2009 and includes a variety of crash characteristics, highway design attributes, driver and vehicle characteristics, and environmental factors. The results from our analysis underscore the value of our proposed model for data fit purposes as well as to accurately estimate variable effects. The most important determinants of injury severity on highways, according to our results, are (1) whether any vehicle occupant is ejected, (2) whether collision type is head-on, (3) whether any vehicle involved in the crash overturned, (4) whether any vehicle occupant is unrestrained by a seat-belt, and (5) whether a commercial truck is involved. Copyright © 2012 Elsevier Ltd. All rights reserved.

Large Truck Crash Causation Study (LTCCS)

Data.gov (United States)

Department of Transportation — The Large Truck* Crash Causation Study (LTCCS) is based on a three-year data collection project conducted by the Federal Motor Carrier Safety Administration (FMCSA)...

THE CRASH INTENSITY EVALUATION USING GENERAL CENTRALITY CRITERIONS AND A GEOGRAPHICALLY WEIGHTED REGRESSION

Directory of Open Access Journals (Sweden)

M. Ghadiriyan Arani

2017-09-01

Full Text Available Today, one of the social problems influencing on the lives of many people is the road traffic crashes especially the highway ones. In this regard, this paper focuses on highway of capital and the most populous city in the U.S. state of Georgia and the ninth largest metropolitan area in the United States namely Atlanta. Geographically weighted regression and general centrality criteria are the aspects of traffic used for this article. In the first step, in order to estimate of crash intensity, it is needed to extract the dual graph from the status of streets and highways to use general centrality criteria. With the help of the graph produced, the criteria are: Degree, Pageranks, Random walk, Eccentricity, Closeness, Betweenness, Clustering coefficient, Eigenvector, and Straightness. The intensity of crash point is counted for every highway by dividing the number of crashes in that highway to the total number of crashes. Intensity of crash point is calculated for each highway. Then, criteria and crash point were normalized and the correlation between them was calculated to determine the criteria that are not dependent on each other. The proposed hybrid approach is a good way to regression issues because these effective measures result to a more desirable output. R2 values for geographically weighted regression using the Gaussian kernel was 0.539 and also 0.684 was obtained using a triple-core cube. The results showed that the triple-core cube kernel is better for modeling the crash intensity.

Cross-sectional study of road accidents and related law enforcement efficiency for 10 countries: A gap coherence analysis.

Science.gov (United States)

Urie, Yohan; Velaga, Nagendra R; Maji, Avijit

2016-10-02

Road crashes are considered as the eighth leading causes of death. There is a wide disparity in crash severity and law enforcement efficiency among low-, medium-, and high-income countries. It would be helpful to review the crash severity trends in these countries, identify the vulnerable road users, and understand the law enforcement effectiveness in devising efficient road safety improvement strategies. The crash severity, fatality rate among various age groups, and law enforcement strategies of 10 countries representing low-income (i.e., India and Morocco), medium-income (i.e. Argentina, South Korea, and Greece), and high-income (i.e., Australia, Canada, France, the UK, and the United States) are studied and compared for a period of 5 years (i.e., 2008 to 2012). The critical parameters affecting road safety are identified and correlated with education, culture, and basic compliance with traffic safety laws. In the process, possible road safety improvement strategies are identified for low-income countries. The number of registered vehicles shows an increasing trend for low-income countries as do the crash rate and crash severity. Compliance related to seat belt and helmet laws is high in high-income countries. In addition, recent seat belt- and helmet-related safety programs in middle-income countries helped to curb fatalities. Noncompliance with safety laws in low-income countries is attributed to education, culture, and inefficient law enforcement. Efficient law enforcement and effective safety education taking into account cultural diversity are the key aspects to reduce traffic-related injuries and fatalities in low-income countries like India.

The influence of road curvature on fatal crashes in New Zealand

DEFF Research Database (Denmark)

Haynes, Robin; Lake, Iain R.; Kingham, Simon

2008-01-01

Bends in roads can cause crashes but a recent study in the UK found that areas with mostly curved roads had lower crash rates than areas with straighter roads. This present study aimed to replicate the previous research in a different country. Variations in the number of fatal road crashes...... occurring between 1996 and 2005 in 73 territorial local authorities across New Zealand were modelled against possible predictors. The predictors were traffic flow, population counts and characteristics, car use, socio-economic deprivation, climate, altitude and road characteristics including four measures...... of average road curvature. The best predictors of the number of fatal crashes on urban roads, rural state highways and other rural roads were traffic flow, speed limitation and socio-economic deprivation. Holding significant factors constant, there was no evidence that TLAs with the most curved roads had...

Rear seat safety: Variation in protection by occupant, crash and vehicle characteristics.

Science.gov (United States)

Durbin, Dennis R; Jermakian, Jessica S; Kallan, Michael J; McCartt, Anne T; Arbogast, Kristy B; Zonfrillo, Mark R; Myers, Rachel K

2015-07-01

Current information on the safety of rear row occupants of all ages is needed to inform further advances in rear seat restraint system design and testing. The objectives of this study were to describe characteristics of occupants in the front and rear rows of model year 2000 and newer vehicles involved in crashes and determine the risk of serious injury for restrained crash-involved rear row occupants and the relative risk of fatal injury for restrained rear row vs. front passenger seat occupants by age group, impact direction, and vehicle model year. Data from the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) and Fatality Analysis Reporting System (FARS) were queried for all crashes during 2007-2012 involving model year 2000 and newer passenger vehicles. Data from NASS-CDS were used to describe characteristics of occupants in the front and rear rows and to determine the risk of serious injury (AIS 3+) for restrained rear row occupants by occupant age, vehicle model year, and impact direction. Using a combined data set containing data on fatalities from FARS and estimates of the total population of occupants in crashes from NASS-CDS, logistic regression modeling was used to compute the relative risk (RR) of death for restrained occupants in the rear vs. front passenger seat by occupant age, impact direction, and vehicle model year. Among all vehicle occupants in tow-away crashes during 2007-2012, 12.3% were in the rear row where the overall risk of serious injury was 1.3%. Among restrained rear row occupants, the risk of serious injury varied by occupant age, with older adults at the highest risk of serious injury (2.9%); by impact direction, with rollover crashes associated with the highest risk (1.5%); and by vehicle model year, with model year 2007 and newer vehicles having the lowest risk of serious injury (0.3%). Relative risk of death was lower for restrained children up to age 8 in the rear compared with passengers in the right

Correlation Analysis of Freeway Traffic Status and Crashes with Nevada Data.

Science.gov (United States)

2017-11-11

This project is to study the correlation between freeway traffic status and crash risks with the historical freeway ITS data and related crash data in Nevada. With the comprehensive review of previous research results, the Center for Advanced Transpo...

Analysis of factors associated with injury severity in crashes involving young New Zealand drivers

DEFF Research Database (Denmark)

Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

2014-01-01

measures within youth-oriented road safety programs. The current study estimates discrete choice models of injury severity of crashes involving young drivers conditional on these crashes having occurred. The analysis examined a comprehensive set of single-vehicle and two-vehicle crashes involving at least...

Analysis of delta velocity and PDOF by means of collision partner and structural involvement in real-life crash pulses with modern passenger cars.

Science.gov (United States)

Iraeus, Johan; Lindquist, Mats

2014-01-01

In the widely used National Automotive Sampling System (NASS)-Crashworthiness Data System (CDS) database, summary metrics that describe crashes are available. Crash angle or principal direction of force (PDOF) is estimated by the crash examiner and velocity changes (ΔV) in the x- and y-directions are calculated by the WinSMASH computer program using PDOF and results from rigid barrier crash testing combined with deformations of the crashed car. In recent years, results from event data recorders (EDRs) have been added to the database. The aim of this study is to compare both PDOF and ΔV between EDR measurements and WinSMASH calculations. NASS-CDS inclusion criteria were model-year 2000 through 2010 automobiles, frontal crashes with ΔV higher than 16 km/h, and the pulse entirely recorded in the EDR module. This resulted in 649 cases. The subject vehicles were further examined and characterized with regard to frontal structure engagement (large or small overlap) as well as collision properties of the partner (impact location; front, side, or back) or object. The EDR crash angle was calculated as the angle between the lateral and longitudinal ΔV at the time of peak longitudinal ΔV. This angle was compared to the NASS-CDS investigator's estimated PDOF with regard to structural engagement and the collision partner or object. Multiple linear regression was used to establish adjustment factors on ΔV and crash angle between the results calculated based on EDR recorded data and that estimated in NASS-CDS. According to this study, simulation in the newest WinSMASH version (2008) underestimates EDR ΔV by 11 percent for large overlap crashes and 17 percent for small overlap impacts. The older WinSMASH version, used prior to 2008, underestimated each one of these two groups by an additional 7 percentage points. Another significant variable to enhance the prediction was whether the crash examiner had reported the WinSMASH estimated ΔV as low or high. In this study, none

General aviation crash safety program at Langley Research Center

Science.gov (United States)

Thomson, R. G.

1976-01-01

The purpose of the crash safety program is to support development of the technology to define and demonstrate new structural concepts for improved crash safety and occupant survivability in general aviation aircraft. The program involves three basic areas of research: full-scale crash simulation testing, nonlinear structural analyses necessary to predict failure modes and collapse mechanisms of the vehicle, and evaluation of energy absorption concepts for specific component design. Both analytical and experimental methods are being used to develop expertise in these areas. Analyses include both simplified procedures for estimating energy absorption capabilities and more complex computer programs for analysis of general airframe response. Full-scale tests of typical structures as well as tests on structural components are being used to verify the analyses and to demonstrate improved design concepts.

Phantom crash confirms models

International Nuclear Information System (INIS)

Anon.

1989-01-01

To test computer models of how a nuclear reactor's containment building would fare if an airplane crashed into it, the Muto Institute in Tokyo sponsored a 3.2 million dollar project at Sandia National Laboratory to slam an F-4 Phantom jet into a 500 ton concrete wall. The results showed that the computer calculations were accurate

Personality of young drivers in Oman: Relationship to risky driving behaviors and crash involvement among Sultan Qaboos University students.

Science.gov (United States)

Al Azri, Mohammed; Al Reesi, Hamed; Al-Adawi, Samir; Al Maniri, Abdullah; Freeman, James

2017-02-17

Drivers' behaviors such as violations and errors have been demonstrated to predict crash involvement among young Omani drivers. However, there is a dearth of studies linking risky driving behaviors to the personality of young drivers. The aim of the present study was to assess such traits within a sample of young Omani drivers (as measured through the behavioral inhibition system [BIS] and the behavioral activation system [BAS]) and determine links with aberrant driving behaviors and self-reported crash involvement. A cross-sectional study was conducted at the Sultan Qaboos University that targeted all licensed Omani's undergraduate students. A total of 529 randomly selected students completed the self-reported questionnaire that included an assessment of driving behaviors (e.g., Driver Behaviour Questionnaire, DBQ) as well as the BIS/BAS measures. A total of 237 participants (44.8%) reported involvement in at least one crash since being licensed. Young drivers with lower BIS-Anxiety scores and higher BAS-Fun Seeking tendencies as well as male drivers were more likely to report driving violations. Statistically significant gender differences were observed on all BIS and BAS subscales (except for BAS-Fun) and the DBQ subscales, because males reported higher trait scores. Though personality traits were related to aberrant driving behaviors at the bivariate level, the constructs were not predictive of engaging in violations or errors. Furthermore, consistent with previous research, a supplementary multivariate logistic regression analysis revealed that only driving experience was predictive of crash involvement. The findings highlight that though personality traits influence self-reported driving styles (and differ between the genders), the relationship with crash involvement is not as clear. This article further outlines the key findings of the study in regards to understanding core psychological constructs that increase crash risk.

Thoracic aortic injury in motor vehicle crashes: the effect of impact direction, side of body struck, and seat belt use.

Science.gov (United States)

Fitzharris, Michael; Franklyn, Melanie; Frampton, Richard; Yang, King; Morris, Andrew; Fildes, Brian

2004-09-01

Using in-depth, real-world motor vehicle crash data from the United States and the United Kingdom, we aimed to assess the incidence and risk factors associated with thoracic aorta injuries. De-identified National Automotive Sampling System Crashworthiness Data System (U.S.) and Co-operative Crash Injury Study (U.K.) data formed the basis of this retrospective analysis. Logistic regression was used to assess the level of risk of thoracic aorta injury associated with impact direction, seat belt use and, given the asymmetry of the thoracic cavity, whether being struck toward the left side of the body was associated with increased risk in side-impact crashes. A total of 13,436 U.S. and 3,756 U.K. drivers and front seat passengers were analyzed. The incidence of thoracic aorta injury in the U.S. and U.K. samples was 1.5% (n = 197) and 1.9% (n = 70), respectively. The risk was higher for occupants seated on the side closest to the impact than for occupants involved in frontal impact crashes. This was the case irrespective of whether the force was applied toward the left (belted: relative risk [RR], 4.6; 95% confidence interval [CI], 2.9-7.1; p direction. Thoracic aorta injuries were found to be associated with high impact severity, and being struck by a sports utility vehicle relative to a passenger vehicle (RR, 1.7; 95% CI, 1.2-2.3; p = 0.001). Aortic injuries have been conventionally associated with frontal impacts. However, emergency clinicians should be aware that occupants of side-impact crashes are at greater risk, particularly if the occupant was unbelted and involved in a crash of high impact severity.

Regulatory Analysis on the Safety Assessment of NPPs against Aircraft Crash

International Nuclear Information System (INIS)

Kim, Sang Yun; Park, Jong Seuk; Chung, Yun Suk; Jung, Rae Young

2011-01-01

Following the 9/11 terror, a new regulation (10CFR 50.150) was enacted in June 2009 in the United States mandating the assessment of new nuclear power plants (NPPs) against intentional aircraft crashes, along with a regulation (10CFR 50.54 (h)(h)) in March 2009 that requires the establishment of accident mitigation measures for NPPs in operation. The UAE requested that the Korean NPP (APR 1400) design meet the U.S.'s new requirements related to the intentional aircraft crash. During the UAE NPP contract bidding process, France claimed that the Korean NPP is vulnerable to aircraft crashes comparing with the French NPP (EPR). Under these international and domestic environments, the necessity to establish a domestic regulation concerning the intentional aircraft crash was raised. This paper proposes a draft regulatory position on this issue through a comprehensive analysis of various influencing factors

Failure analysis of parameter-induced simulation crashes in climate models

Science.gov (United States)

Lucas, D. D.; Klein, R.; Tannahill, J.; Ivanova, D.; Brandon, S.; Domyancic, D.; Zhang, Y.

2013-08-01

Simulations using IPCC (Intergovernmental Panel on Climate Change)-class climate models are subject to fail or crash for a variety of reasons. Quantitative analysis of the failures can yield useful insights to better understand and improve the models. During the course of uncertainty quantification (UQ) ensemble simulations to assess the effects of ocean model parameter uncertainties on climate simulations, we experienced a series of simulation crashes within the Parallel Ocean Program (POP2) component of the Community Climate System Model (CCSM4). About 8.5% of our CCSM4 simulations failed for numerical reasons at combinations of POP2 parameter values. We applied support vector machine (SVM) classification from machine learning to quantify and predict the probability of failure as a function of the values of 18 POP2 parameters. A committee of SVM classifiers readily predicted model failures in an independent validation ensemble, as assessed by the area under the receiver operating characteristic (ROC) curve metric (AUC > 0.96). The causes of the simulation failures were determined through a global sensitivity analysis. Combinations of 8 parameters related to ocean mixing and viscosity from three different POP2 parameterizations were the major sources of the failures. This information can be used to improve POP2 and CCSM4 by incorporating correlations across the relevant parameters. Our method can also be used to quantify, predict, and understand simulation crashes in other complex geoscientific models.

A mixed logit analysis of two-vehicle crash severities involving a motorcycle.

Science.gov (United States)

Shaheed, Mohammad Saad B; Gkritza, Konstantina; Zhang, Wei; Hans, Zachary

2013-12-01

Using motorcycle crash data for Iowa from 2001 to 2008, this paper estimates a mixed logit model to investigate the factors that affect crash severity outcomes in a collision between a motorcycle and another vehicle. These include crash-specific factors (such as manner of collision, motorcycle rider and non-motorcycle driver and vehicle actions), roadway and environmental conditions, location and time, motorcycle rider and non-motorcycle driver and vehicle attributes. The methodological approach allows the parameters to vary across observations as opposed to a single parameter representing all observations. Our results showed non-uniform effects of rear-end collisions on minor injury crashes, as well as of the roadway speed limit greater or equal to 55mph, the type of area (urban), the riding season (summer) and motorcyclist's gender on low severity crashes. We also found significant effects of the roadway surface condition, clear vision (not obscured by moving vehicles, trees, buildings, or other), light conditions, speed limit, and helmet use on severe injury outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

The association of graduated driver licensing with miles driven and fatal crash rates per miles driven among adolescents.

Science.gov (United States)

Zhu, Motao; Cummings, Peter; Zhao, Songzhu; Coben, Jeffrey H; Smith, Gordon S

2015-04-01

Graduated driver licensing (GDL) laws are associated with reduced crash rates per person-year among adolescents. It is unknown whether adolescents crash less per miles driven or drive less under GDL policies. We used data from the US National Household Travel Survey and Fatality Analysis Reporting System for 1995-1996, 2001-2002 and 2008-2009. We compared adolescents subject to GDL laws with those not by estimating adjusted IRRs for being a driver in a crash with a death per person-year (aIRRpy) and per miles driven (aIRRm), and adjusted miles driven ratios (aMR) controlling for changes in rates over time. Comparing persons subject to GDL policies with those not, 16 year olds had fewer fatal crashes per person-year (aIRRpy 0.63, 95% CI 0.47 to 0.91), drove fewer miles (aMR 0.79, 95% CI 0.63 to 0.98) and had lower crash rates per miles driven (aIRRm 0.83, 95% CI 0.65 to 1.06). For age 17, the aIRRpy was 0.83 (95% CI 0.60 to 1.17), the aMR 0.80 (95% CI 0.63 to 1.03) and the aIRRm 1.03 (95% CI 0.80 to 1.35). For age 18, the aIRRpy was 0.93 (95% CI 0.72 to 1.19), the aMR 0.92 (95% CI 0.77 to 1.09) and the aIRRm 1.01 (95% CI 0.84 to 1.23). If these associations are causal, GDL laws reduced crashes per person-year by about one-third among 16 year olds; half the reduction was due to fewer crashes per miles driven and half to less driving. For ages 17 and 18, there was no evidence of reduced crash rates per miles driven. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Fatigue-related crashes involving express buses in Malaysia: will the proposed policy of banning the early-hour operation reduce fatigue-related crashes and benefit overall road safety?

Science.gov (United States)

Mohamed, Norlen; Mohd-Yusoff, Mohammad-Fadhli; Othman, Ilhamah; Zulkipli, Zarir-Hafiz; Osman, Mohd Rasid; Voon, Wong Shaw

2012-03-01

Fatigue-related crashes have long been the topic of discussion and study worldwide. The relationship between fatigue-related crashes and time of day is well documented. In Malaysia, the possibility of banning express buses from operating during the early-hours of the morning has emerged as an important consideration for passenger safety. This paper highlights the findings of an impact assessment study. The study was conducted to determine all possible impacts prior to the government making any decision on the proposed banning. This study is an example of a simple and inexpensive approach that may influence future policy-making process. The impact assessment comprised two major steps. The first step involved profiling existing operation scenarios, gathering information on crashes involving public express buses and stakeholders' views. The second step involved a qualitative impact assessment analysis using all information gathered during the profiling stage to describe the possible impacts. Based on the assessment, the move to ban early-hour operations could possibly result in further negative impacts on the overall road safety agenda. These negative impacts may occur if the fundamental issues, such as driving and working hours, and the need for rest and sleep facilities for drivers, are not addressed. In addition, a safer and more accessible public transportation system as an alternative for those who choose to travel at night would be required. The proposed banning of early-hour operations is also not a feasible solution for sustainability of express bus operations in Malaysia, especially for those operating long journeys. The paper concludes by highlighting the need to design a more holistic approach for preventing fatigue-related crashes involving express buses in Malaysia. Copyright © 2011 Elsevier Ltd. All rights reserved.

Social costs of road crashes: An international analysis.

Science.gov (United States)

Wijnen, Wim; Stipdonk, Henk

2016-09-01

This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income countries (HICs) and seven low and middle income countries (LMICs). Costs are expressed as a proportion of the gross domestic product (GDP). Differences between countries are described and explained. These are partly a consequence of differences in the road safety level, but there are also methodological explanations. Countries may or may not correct for underreporting of road crashes, they may or may not use the internationally recommended willingness to pay (WTP)-method for estimating human costs, and there are methodological differences regarding the calculation of some other cost components. The analysis shows that the social costs of road crashes in HICs range from 0.5% to 6.0% of the GDP with an average of 2.7%. Excluding countries that do not use a WTP- method for estimating human costs and countries that do not correct for underreporting, results in average costs of 3.3% of GDP. For LMICs that do correct for underreporting the share in GDP ranges from 1.1% to 2.9%. However, none of the LMICs included has performed a WTP study of the human costs. A major part of the costs is related to injuries: an average share of 50% for both HICs and LMICs. The average share of fatalities in the costs is 23% and 30% respectively. Prevention of injuries is thus important to bring down the socio-economic burden of road crashes. The paper shows that there are methodological differences between countries regarding cost components that are taken into account and regarding the methods used to estimate specific cost components. In order to be able to make sound comparisons of the costs of road crashes across countries, (further) harmonization of cost studies is recommended. This can be

Relationship between areas of cognitive functioning on the Mini-Mental State Examination and crash risk.

Science.gov (United States)

Huisingh, Carrie; Wadley, Virginia G; McGwin, Gerald; Owsley, Cynthia

2018-03-01

Previous studies have suggested that the pattern of cognitive impairment in crash involved older drivers is different from non-crash involved older drivers. This study assessed the relationship between seven areas of cognitive functioning (orientation to time, orientation to place, registration, attention and calculation, recall, language, and visual construction) on the Mini-Mental State Examination (MMSE) collected at baseline and rates of future crash involvement in a prospective population-based sample of older drivers. Motor vehicle collision involvement was obtained from the Alabama Department of Public Safety. Poisson regression was used to calculate crude and adjusted rate ratios (RR). Older drivers having difficulties in place orientation were more than 6 times (95% CI 1.90-19.86) more likely to be involved in a future crash (adjusted RR = 6.14, 95% confidence interval (CI) 1.90-19.86) and at-fault crash (adjusted RR=6.39, 95% CI 1.51-27.10). Impairment in the other cognitive areas was not associated with higher rates of crash or at-fault crash involvement. The findings were validated in an independent sample of high-risk older drivers and a similar pattern of results was observed. Spatial orientation impairment can help identify older drivers who are more likely to crash in the future.

Transport company safety climate - the impact on truck driver behaviour and crash involvement

OpenAIRE

Sullman, Mark J. M.; Stephens A. N.; Pajo K.

2017-01-01

Objective: The present study investigated the relationships between safety climate and driving behavior and crash involvement. Methods: A total of 339 company-employed truck drivers completed a questionnaire that measured their perceptions of safety climate, crash record, speed choice, and aberrant driving behaviors (errors, lapses, and violations). Results: Although there was no direct relationship between the drivers' perceptions of safety climate and crash involvement, safety clima...

Economic Cost of Crashes in Idaho

Science.gov (United States)

2016-06-01

The Idaho Transportation Departments Office of Highway Safety contracted with Cambridge Systematics (CS) for an assessment of the feasibility of calculating the Idaho-specific economic and comprehensive costs associated with vehicle crashes. Resea...

Novice drivers' risky driving behavior, risk perception, and crash risk: findings from the DRIVE study.

Science.gov (United States)

Ivers, Rebecca; Senserrick, Teresa; Boufous, Soufiane; Stevenson, Mark; Chen, Huei-Yang; Woodward, Mark; Norton, Robyn

2009-09-01

We explored the risky driving behaviors and risk perceptions of a cohort of young novice drivers and sought to determine their associations with crash risk. Provisional drivers aged 17 to 24 (n = 20 822) completed a detailed questionnaire that included measures of risk perception and behaviors; 2 years following recruitment, survey data were linked to licensing and police-reported crash data. Poisson regression models that adjusted for multiple confounders were created to explore crash risk. High scores on questionnaire items for risky driving were associated with a 50% increased crash risk (adjusted relative risk = 1.51; 95% confidence interval = 1.25, 1.81). High scores for risk perception (poorer perceptions of safety) were also associated with increased crash risk in univariate and multivariate models; however, significance was not sustained after adjustment for risky driving. The overrepresentation of youths in crashes involving casualties is a significant public health issue. Risky driving behavior is strongly linked to crash risk among young drivers and overrides the importance of risk perceptions. Systemwide intervention, including licensing reform, is warranted.

Injury risks for on-road farm equipment and horse and buggy crashes in Pennsylvania: 2010-2013.

Science.gov (United States)

Gorucu, Serap; Murphy, Dennis J; Kassab, Cathy

2017-04-03

The purpose of this study was to investigate characteristics associated with farm equipment and horse and buggy roadway crashes in relation to person, incident, and injury characteristics to identify appropriate points for injury incident prevention. Information on crashes occurring on public roads during the years 2010-2013 was obtained from the Pennsylvania Department of Transportation (PennDOT) and analyzed. There were 344 farm equipment and 246 horse and buggy crashes during the 4-year study period. These crashes involved 666 and 504 vehicles and 780 and 838 people, respectively. In incidents with farm equipment, the non-farm equipment drivers had an almost 2 times greater injury risk than farm equipment operators. Horse and buggy crashes were almost 3 times more injurious to the horse and buggy drivers than the drivers of the other vehicles. The average crash rate for farm equipment was 198.4 crashes per 100,000 farm population and for horse and buggy the crash rate was calculated as 89.4 crashes per 100,000 Amish population per year. This study suggests that road safety and public health programs should focus not only on farm equipment operators and horse and buggy drivers but on other motorists sharing the roadway with them.

A comparative empirical analysis of statistical models for evaluating highway segment crash frequency

Directory of Open Access Journals (Sweden)

Bismark R.D.K. Agbelie

2016-08-01

Full Text Available The present study conducted an empirical highway segment crash frequency analysis on the basis of fixed-parameters negative binomial and random-parameters negative binomial models. Using a 4-year data from a total of 158 highway segments, with a total of 11,168 crashes, the results from both models were presented, discussed, and compared. About 58% of the selected variables produced normally distributed parameters across highway segments, while the remaining produced fixed parameters. The presence of a noise barrier along a highway segment would increase mean annual crash frequency by 0.492 for 88.21% of the highway segments, and would decrease crash frequency for 11.79% of the remaining highway segments. Besides, the number of vertical curves per mile along a segment would increase mean annual crash frequency by 0.006 for 84.13% of the highway segments, and would decrease crash frequency for 15.87% of the remaining highway segments. Thus, constraining the parameters to be fixed across all highway segments would lead to an inaccurate conclusion. Although, the estimated parameters from both models showed consistency in direction, the magnitudes were significantly different. Out of the two models, the random-parameters negative binomial model was found to be statistically superior in evaluating highway segment crashes compared with the fixed-parameters negative binomial model. On average, the marginal effects from the fixed-parameters negative binomial model were observed to be significantly overestimated compared with those from the random-parameters negative binomial model.

Obesity and non-fatal motor vehicle crash injuries: sex difference effects.

Science.gov (United States)

Ma, X; Laud, P W; Pintar, F; Kim, J-E; Shih, A; Shen, W; Heymsfield, S B; Allison, D B; Zhu, S

2011-09-01

Obesity and motor vehicle crash (MVC) injuries are two parallel epidemics in the United States. An important unanswered question is whether there are sex differences in the associations between the presence of obesity and non-fatal MVC injuries. To further understand the association between obesity and non-fatal MVC injuries, particularly the sex differences in these relations. We examined this question by analyzing data from the 2003 to 2007 National Automotive Sampling System Crashworthiness Data System (NASS CDS). A total of 10,962 drivers who were aged 18 years or older and who survived frontal collision crashes were eligible for the study. Male drivers experienced a lower rate of overall non-fatal MVC injuries than did female drivers (38.1 versus 52.2%), but experienced a higher rate of severe injuries (0.7 versus 0.2%). After adjusting for change in velocity (ΔV) during the crashes, obese male drivers showed a much higher risk (logistic coefficients of body mass index (BMI) for moderate, serious and severe injury are 0.0766, 0.1470 and 0.1792, respectively; all Pobese male drivers and these risks increased with injury severity. Non-fatal injury risks were not found to be increased in obese female drivers. The association between obesity and risk of non-fatal injury was much stronger for male drivers than for female drivers. The higher risk of non-fatal MVC injuries in obese male drivers might result from their different body shape and fat distribution compared with obese female drivers. Our findings should be considered for obesity reduction, traffic safety evaluation and vehicle design for obese male drivers and provide testable hypotheses for future studies.

Crash simulations for interior design

NARCIS (Netherlands)

Poeze, E.; Slaats, P.M.A.

1996-01-01

With the increasing number of compact cars, safety aspects becomes increasingly important for interior designs. The smaller dimensions of these cars do not only decrease the car mass, but also the energy absorption length, resulting in a more severe crash pulse. As a consequence, the inertia loading

2008 Michigan traffic crash facts

Science.gov (United States)

2009-03-18

In keeping with recent trends, traffic fatalities in 2008 were down to 980, a 9.6 : percent decrease from last year. The total number of persons injured also declined : 7.5 percent to 74,568 and total crashes dropped 2.5 percent to 316,057. Most : no...

2009 Michigan traffic crash facts

Science.gov (United States)

2010-01-01

In keeping with recent trends, traffic fatalities in 2009 were down to 871, a 11.1 : percent decrease from last year. The total number of persons injured also declined : 4.9 percent to 70,931 and total crashes dropped 7.9 percent to 290,978. Most : n...

Motor Vehicle Crash Injuries PSA (:60)

Centers for Disease Control (CDC) Podcasts

This 60 second Public Service Announcement is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.

Geospatial and machine learning techniques for wicked social science problems: analysis of crash severity on a regional highway corridor

Science.gov (United States)

Effati, Meysam; Thill, Jean-Claude; Shabani, Shahin

2015-04-01

The contention of this paper is that many social science research problems are too "wicked" to be suitably studied using conventional statistical and regression-based methods of data analysis. This paper argues that an integrated geospatial approach based on methods of machine learning is well suited to this purpose. Recognizing the intrinsic wickedness of traffic safety issues, such approach is used to unravel the complexity of traffic crash severity on highway corridors as an example of such problems. The support vector machine (SVM) and coactive neuro-fuzzy inference system (CANFIS) algorithms are tested as inferential engines to predict crash severity and uncover spatial and non-spatial factors that systematically relate to crash severity, while a sensitivity analysis is conducted to determine the relative influence of crash severity factors. Different specifications of the two methods are implemented, trained, and evaluated against crash events recorded over a 4-year period on a regional highway corridor in Northern Iran. Overall, the SVM model outperforms CANFIS by a notable margin. The combined use of spatial analysis and artificial intelligence is effective at identifying leading factors of crash severity, while explicitly accounting for spatial dependence and spatial heterogeneity effects. Thanks to the demonstrated effectiveness of a sensitivity analysis, this approach produces comprehensive results that are consistent with existing traffic safety theories and supports the prioritization of effective safety measures that are geographically targeted and behaviorally sound on regional highway corridors.

The Effects of Curtain Airbag on Occupant Kinematics and Injury Index in Rollover Crash

Directory of Open Access Journals (Sweden)

Hongyun Li

2018-01-01

Full Text Available Background. Occupant injuries in rollover crashes are associated with vehicle structural performance, as well as the restraint system design. For a better understanding of the occupant kinematics and injury index in certain rollover crash, it is essential to carry out dynamic vehicle rollover simulation with dummy included. Objective. This study focused on effects of curtain airbag (CAB parameters on occupant kinematics and injury indexes in a rollover crash. Besides, optimized parameters of the CAB were proposed for the purpose of decreasing the occupant injuries in such rollover scenario. Method and Material. The vehicle motion from the physical test was introduced as the input for the numerical simulation, and the 50% Hybrid III dummy model from the MADYMO database was imported into a simulation model. The restraint system, including a validated CAB module, was introduced for occupant kinematics simulation and injury evaluation. TTF setting, maximum inflator pressure, and protection area of the CAB were analysed. Results. After introducing the curtain airbag, the maximum head acceleration was reduced from 91.60 g to 49.52 g, and the neck Mx and neck Fz were reduced significantly. Among these CAB parameters, the TTF setting had the largest effect on the head acceleration which could reduce 8.6 g furthermore after optimization. The neck Fz was decreased from 3766.48 N to 2571.77 N after optimization of CAB protection area. Conclusions. Avoiding hard contact is critical for the occupant protection in the rollover crashes. The simulation results indicated that occupant kinematics and certain injury indexes were improved with the help of CAB in such rollover scenario. Appropriate TTF setting and inflator selection could benefit occupant kinematics and injury indexes. Besides, it was advised to optimize the curtain airbag thickness around the head contact area to improve head and neck injury indexes.

Crash fatality and vehicle incompatibility in collisions between cars and light trucks or vans.

Science.gov (United States)

Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara

2014-12-01

In crashes between a car and a light truck or van (LTV), car occupants are more likely to be killed than LTV occupants. The extent this is due to the greater harm imposed by LTVs on cars or the greater protection they offer their own occupants is not known. We conducted a case-control study of collisions between two passenger vehicles in the USA during 1990-2008. Cases were all decedents in fatal crashes (N=157,684); one control was selected from each crash in a national probability sample of crashes (N=379,458). Adjusted for the type of vehicle they were riding in and other confounders, occupants of vehicles colliding with any type of LTVs (categorised as compact sport utility vehicles (SUV), full-size SUVs, minivans, full-size vans, compact pickups and full-size pickups) were at higher risk of death compared with occupants colliding with cars. Adjusted for the type of vehicle they crashed with and other confounders, occupants of LTVs in a collision with any vehicle were at lower risk of death compared with car occupants. Compared with a crash between two cars, the overall RR of death in a crash between any of the other 27 different combinations of vehicle types was 1.0 or greater, except for crashes between two full-size pickups, where the RR of death was 0.9. Although LTVs protect their own occupants better than cars do, LTVs are associated with an excess total risk of death in crashes with cars or other LTVs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Development and evaluation of a web-based software for crash data collection, processing and analysis.

Science.gov (United States)

Montella, Alfonso; Chiaradonna, Salvatore; Criscuolo, Giorgio; De Martino, Salvatore

2017-02-05

First step of the development of an effective safety management system is to create reliable crash databases since the quality of decision making in road safety depends on the quality of the data on which decisions are based. Improving crash data is a worldwide priority, as highlighted in the Global Plan for the Decade of Action for Road Safety adopted by the United Nations, which recognizes that the overall goal of the plan will be attained improving the quality of data collection at the national, regional and global levels. Crash databases provide the basic information for effective highway safety efforts at any level of government, but lack of uniformity among countries and among the different jurisdictions in the same country is observed. Several existing databases show significant drawbacks which hinder their effective use for safety analysis and improvement. Furthermore, modern technologies offer great potential for significant improvements of existing methods and procedures for crash data collection, processing and analysis. To address these issues, in this paper we present the development and evaluation of a web-based platform-independent software for crash data collection, processing and analysis. The software is designed for mobile and desktop electronic devices and enables a guided and automated drafting of the crash report, assisting police officers both on-site and in the office. The software development was based both on the detailed critical review of existing Australasian, EU, and U.S. crash databases and software as well as on the continuous consultation with the stakeholders. The evaluation was carried out comparing the completeness, timeliness, and accuracy of crash data before and after the use of the software in the city of Vico Equense, in south of Italy showing significant advantages. The amount of collected information increased from 82 variables to 268 variables, i.e., a 227% increase. The time saving was more than one hour per crash, i

Propensity scores-potential outcomes framework to incorporate severity probabilities in the highway safety manual crash prediction algorithm.

Science.gov (United States)

Sasidharan, Lekshmi; Donnell, Eric T

2014-10-01

Accurate estimation of the expected number of crashes at different severity levels for entities with and without countermeasures plays a vital role in selecting countermeasures in the framework of the safety management process. The current practice is to use the American Association of State Highway and Transportation Officials' Highway Safety Manual crash prediction algorithms, which combine safety performance functions and crash modification factors, to estimate the effects of safety countermeasures on different highway and street facility types. Many of these crash prediction algorithms are based solely on crash frequency, or assume that severity outcomes are unchanged when planning for, or implementing, safety countermeasures. Failing to account for the uncertainty associated with crash severity outcomes, and assuming crash severity distributions remain unchanged in safety performance evaluations, limits the utility of the Highway Safety Manual crash prediction algorithms in assessing the effect of safety countermeasures on crash severity. This study demonstrates the application of a propensity scores-potential outcomes framework to estimate the probability distribution for the occurrence of different crash severity levels by accounting for the uncertainties associated with them. The probability of fatal and severe injury crash occurrence at lighted and unlighted intersections is estimated in this paper using data from Minnesota. The results show that the expected probability of occurrence of fatal and severe injury crashes at a lighted intersection was 1 in 35 crashes and the estimated risk ratio indicates that the respective probabilities at an unlighted intersection was 1.14 times higher compared to lighted intersections. The results from the potential outcomes-propensity scores framework are compared to results obtained from traditional binary logit models, without application of propensity scores matching. Traditional binary logit analysis suggests that

Modeling the effect of operator and passenger characteristics on the fatality risk of motorcycle crashes.

Science.gov (United States)

Tavakoli Kashani, Ali; Rabieyan, Rahim; Besharati, Mohammad Mehdi

2016-01-01

In Iran more than 25% of crash fatalities belong to motorcycle operators and passengers in the recent years, from which about 20% are related to passenger fatalities. The aim of this study was to investigate the motorcycle operator and passenger characteristics as well as other contributory factors that may affect the fatality risk of motorcyclists involved in traffic crashes. To this end, motorcycle crash data between 2009 and 2012 was extracted from Iran traffic crash database and a logistic regression analysis was performed to obtain odds ratio estimates for each of the study variables. The fatality risk of motorcyclists has a direct relationship with the number of pillion passengers carried. Results also indicate that the amount of increase in the likelihood of having a fatality in a motorcycles crash is considerably higher when the operator is accompanied by a male passenger of the same age. Furthermore, results showed that if the crash is occurred in the darkness, on curves, in rural areas and on highways, then the crash would be more likely to be fatal. Moreover, the head-on collisions, older operators, unlicensed operators and not using a safety helmet were found to increase the likelihood of a fatality in a motorcycle crash. Preventative measures such as, imposing stricter rules regarding safety helmet usage and confining the number of pillion passengers to one, might be implemented to reduce the fatality risk in motorcycle crashes. In addition, more appropriate infrastructures for penalizing offending motorcyclists could also reduce the frequency of law violations such as not wearing helmet or riding without motorcycle license, which in turn, would result into a reduction in the fatality risk of motorcycle crashes. © 2016 KUMS, All rights reserved.

Is Cannabis Use Related to Road Crashes? A Study of Long ...

African Journals Online (AJOL)

Factors associated with driving under the influence of cannabis (DUIC) and related road crashes among 422 commercial drivers were studied. A multivariate analysis was conducted to understand the associations between risk factors and DUIC and car crashes respectively. Young age, OR = 3.6, 95% CI 1.9-7.6; cannabis ...

75 FR 6123 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection

Science.gov (United States)

2010-02-08

... motor vehicle safety standard is in effect under this chapter, a State or a political subdivision of a... [Docket No. NHTSA-2009-0156] RIN 2127-AK57 Federal Motor Vehicle Safety Standards; Occupant Crash...'s response to petitions for reconsideration of a November 12, 2008 final rule that amended the child...

Technostress: Surviving a Database Crash.

Science.gov (United States)

Dobb, Linda S.

1990-01-01

Discussion of technostress in libraries focuses on a database crash at California Polytechnic State University, San Luis Obispo. Steps taken to restore the data are explained, strategies for handling technological accidents are suggested, the impact on library staff is discussed, and a 10-item annotated bibliography on technostress is provided.…

Development of a prediction model for crash occurrence by analyzing traffic crash and citation data : final report.

Science.gov (United States)

2017-04-30

It is commonly acknowledged that factors such as human factors, vehicle characteristics, road design and environmental factors highly contribute to the occurrence of traffic crashes (WHO, 2004). Since human factors usually have the most significant i...

Patologia da comunicação: Crash sem pentecostes

Directory of Open Access Journals (Sweden)

Olgária Chain Féres Matos

2008-11-01

Full Text Available O objetivo do ensaio é mostrar a metrópole como o sujeito histórico da contemporaneidade, por meio da análise do filme Crash. Ela é o microcosmo em que se comunicam indivíduos pela mediação do automóvel. Nela inscrevem-se as relações sociais e seus conflitos: xenofobia, racismo, particularismos legais e desregulamentações políticas. Mundo menos dominado por pessoas e mais pelo acaso, ele resulta da determinação de todas as esferas da vida pelo fator econômico e pelas derivas do mercado mundial, forma moderna do destino. Palavras-chave: crash; estado de direito; estado de exceção; fundamentalismos Abstract: The Pathology of Communication: Crash without Pentecost — The purpose of this essay is to portray the metropolis as the historical subject of contemporaneousness, based on an analysis of the movie Crash, which illustrates the microcosm in which individual communications are mediated by the automobile and which is marked by social relations and their conflicts: xenophobia, racism, legal particularities and political deregulation. A world ruled by fortuitousness rather than by human will, it is the product of the determination of all spheres of life by economic factors and by global market trends, seen as the modern depiction of fate. Keywords: Crash; rule of law; rule of exception; fundamentalism

Tool to manage Road Safety Deficiencies and risk of highway crashes

Energy Technology Data Exchange (ETDEWEB)

Lopez Maldonado, G.; Baena Ruiz, L.; Garach Morcillo, L.; Oña Lopez, J. de

2016-07-01

In order to facilitate the management of the results obtained in the project “Analysis of the relationship between Road Safety Deficiencies, crashes and hazardous sections” financed by Public Works Agency of the Regional Government of Andalusia (AOPJA) and led by the research group TRYSE from University of Granada, a safety management tool has been developed. This application allows safety managers to consult some factors affecting crashes on two-lane rural highways.The main aim of that project was to analyze the influence of some road deficiencies on crashes and hazardous sections in the Complementary Road Network of Andalusia. These deficiencies were defined in a checklist and were identified by a road inspection. Decision Trees (DTs), that are a data mining technique that allows the extraction of Decision Rules (DRs), were used. DRs revealed the relationship between road deficiencies and crashes.The application allows two different analyses. A specific analysis of the Complementary Road Network of Andalusia, in which, particular safety problems can be identified, and the location of roads with those problems can be obtained. A more general analysis in which some characteristics related to road safety can be selected in order to know the combination of factors contributing to traffic crashes. Safety problems are based on data from Complementary Road Network of Andalusia but results can be extrapolated to other rural highways in Spain. (Author)

Association between commercial vehicle driver at-fault crashes involving sleepiness/fatigue and proximity to rest areas and truck stops.

Science.gov (United States)

Bunn, Terry L; Slavova, Svetla; Rock, Peter J

2017-11-22

There is ongoing concern at the national level about the availability of adequate commercial vehicle rest areas and truck stops for commercial vehicle drivers to rest or to wait for a delivery window. A retrospective case-control study was conducted to determine the association between the occurrence of sleepiness/fatigue-related (cases) vs. all other human factor-related commercial vehicle driver at-fault crashes (controls) and proximity to rest areas, weigh stations with rest havens, and truck stops. Commercial vehicle driver at-fault crashes involving sleepiness/fatigue were more likely to occur on roadways where the nearest rest areas/weigh stations with rest havens/truck stops were located 20 miles or more from the commercial vehicle crash site (Odds Ratio [OR]=2.32; Confidence Interval [CI] 1.615, 3.335] for 20-39.9 miles vs. commercial vehicle at-fault driver crashes with human factors other than sleepiness/fatigue cited in crash reports. Commercial vehicle driver at-fault crashes involving sleepiness/fatigue also were more likely to occur on parkways compared to interstates (adjusted OR=3.747 [CI 2.83, 4.95]), during nighttime hours (adjusted OR=6.199 [CI 4.733, 8.119]), and on dry pavement (adjusted OR 1.909, [CI 1.373, 2.655]). The use of statewide crash data analysis coupled with ArcGIS mapping capabilities provided the opportunity to both statistically determine and to visualize the association between rest area/weigh station with rest haven/truck stop distance and the occurrence of commercial vehicle driver at-fault crashes involving sleepiness/fatigue. Implementation and evaluation of commercial vehicle employer policies and interventions such as the use of commercial vehicle driver fatigue alert systems may help to reduce fatigue and sleepiness in commercial vehicle drivers. These results can be used by state and local highway transportation officials to inform and increase truck parking availability, especially on parkways. Copyright © 2017

Symposium: "Crash": Rhetorically Wrecking Discourses of Race, Tolerance, and White Privilege

Science.gov (United States)

Nunley, Vorris L.

2007-01-01

From within the milieu of race and identity fatigue emerges "Crash." Winner of three Academy Awards, including Best Picture, "Crash" addresses how the fluidity of identity is pooled, ebbed, blocked, directed, dammed up. How identity and subjectivity are dammed up and mediated through the force of the anxieties, fears, and frustrations of people…

A survey on the effects of institutional ownership, internal audit and non-executive board members on forecasting crashes: Evidence from Tehran Stock Exchange

Directory of Open Access Journals (Sweden)

Mostafa Sohouli Vahed

2014-11-01

Full Text Available This paper presents an empirical investigation to study the effects of institutional ownership, internal audit system, the number of non-executive board members and having differentiation between chair and general managers’ responsibilities on the likelihood of stock price crash on 110 listed firms on Tehran Stock Exchange over the period 2004-2011. The study uses Chen’ model (2001 [Chen, J., Hong, H., & Stein, J. C. (2001. Forecasting crashes: Trading volume, past returns, and conditional skewness in stock prices. Journal of Financial Economics, 61(3, 345-381.] to perform the investigation. Based on the results of the survey, there is a negative and meaningful relationship between stock price crash and institutional ownership when the level of significance is ten percent. In addition, as the number of non-executive board members increases, the chance of stock price crash decreases when the level of significance is five percent. However, separation between the responsibility of chair and general managers did not seem to influence on stock price and also having internal audit system had no impact on the likelihood of stock price change.

EMS Provider Assessment of Vehicle Damage Compared to a Professional Crash Reconstructionist

Science.gov (United States)

Lerner, E. Brooke; Cushman, Jeremy T.; Blatt, Alan; Lawrence, Richard; Shah, Manish N.; Swor, Robert; Brasel, Karen; Jurkovich, Gregory J.

2011-01-01

Objective To determine the accuracy of EMS provider assessments of motor vehicle damage, when compared to measurements made by a professional crash reconstructionist. Methods EMS providers caring for adult patients injured during a motor vehicle crash and transported to the regional trauma center in a midsized community were interviewed upon ED arrival. The interview collected provider estimates of crash mechanism of injury. For crashes that met a preset severity threshold, the vehicle’s owner was asked to consent to having a crash reconstructionist assess their vehicle. The assessment included measuring intrusion and external auto deformity. Vehicle damage was used to calculate change in velocity. Paired t-test and correlation were used to compare EMS estimates and investigator derived values. Results 91 vehicles were enrolled; of these 58 were inspected and 33 were excluded because the vehicle was not accessible. 6 vehicles had multiple patients. Therefore, a total of 68 EMS estimates were compared to the inspection findings. Patients were 46% male, 28% admitted to hospital, and 1% died. Mean EMS estimated deformity was 18” and mean measured was 14”. Mean EMS estimated intrusion was 5” and mean measured was 4”. EMS providers and the reconstructionist had 67% agreement for determination of external auto deformity (kappa 0.26), and 88% agreement for determination of intrusion (kappa 0.27) when the 1999 Field Triage Decision Scheme Criteria were applied. Mean EMS estimated speed prior to the crash was 48 mph±13 and mean reconstructionist estimated change in velocity was 18 mph±12 (correlation -0.45). EMS determined that 19 vehicles had rolled over while the investigator identified 18 (kappa 0.96). In 55 cases EMS and the investigator agreed on seatbelt use, for the remaining 13 cases there was disagreement (5) or the investigator was unable to make a determination (8) (kappa 0.40). Conclusions This study found that EMS providers are good at estimating

Predicting Crashes Using Traffic Offences. A Meta-Analysis that Examines Potential Bias between Self-Report and Archival Data

Science.gov (United States)

af Wåhlberg, Anders; Freeman, James; Watson, Barry; Watson, Angela

2016-01-01

Background Traffic offences have been considered an important predictor of crash involvement, and have often been used as a proxy safety variable for crashes. However the association between crashes and offences has never been meta-analysed and the population effect size never established. Research is yet to determine the extent to which this relationship may be spuriously inflated through systematic measurement error, with obvious implications for researchers endeavouring to accurately identify salient factors predictive of crashes. Methodology and Principal Findings Studies yielding a correlation between crashes and traffic offences were collated and a meta-analysis of 144 effects drawn from 99 road safety studies conducted. Potential impact of factors such as age, time period, crash and offence rates, crash severity and data type, sourced from either self-report surveys or archival records, were considered and discussed. After weighting for sample size, an average correlation of r = .18 was observed over the mean time period of 3.2 years. Evidence emerged suggesting the strength of this correlation is decreasing over time. Stronger correlations between crashes and offences were generally found in studies involving younger drivers. Consistent with common method variance effects, a within country analysis found stronger effect sizes in self-reported data even controlling for crash mean. Significance The effectiveness of traffic offences as a proxy for crashes may be limited. Inclusion of elements such as independently validated crash and offence histories or accurate measures of exposure to the road would facilitate a better understanding of the factors that influence crash involvement. PMID:27128093

A simulator-based analysis of engineering treatments for right-hook bicycle crashes at signalized intersections.

Science.gov (United States)

Warner, Jennifer; Hurwitz, David S; Monsere, Christopher M; Fleskes, Kayla

2017-07-01

A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures - regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design - at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with a shared right-turn and through lane. Changes in driver performance in response to treatments were measured in a high-fidelity driving simulator. Twenty-eight participants each completed 22 right-turn maneuvers. A partially counterbalanced experimental design exposed drivers to critical scenarios, which had been determined in a previous experiment. For each turn, driver performance measures, including visual attention, crash avoidance, and potential crash severity, were collected. A total of 75 incidents (47 near-collisions and 28 collisions) were observed during the 616 right turns. All treatments had some positive effect on measured driver performance with respect to the right-turn vehicle conflicts. Further work is required to map the magnitude of these changes in driver performance to crash-based outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Crash prediction model for two-lane rural highways in the Ashanti region of Ghana

Directory of Open Access Journals (Sweden)

Williams Ackaah

2011-07-01

Full Text Available Crash Prediction Models (CPMs have been used elsewhere as a useful tool by road Engineers and Planners. There is however no study on the prediction of road traffic crashes on rural highways in Ghana. The main objective of the study was to develop a prediction model for road traffic crashes occurring on the rural sections of the highways in the Ashanti Region of Ghana. The model was developed for all injury crashes occurring on selected rural highways in the Region over the three (3 year period 2005–2007. Data was collected from 76 rural highway sections and each section varied between 0.8 km and 6.7 km. Data collected for each section comprised injury crash data, traffic flow and speed data, and roadway characteristics and road geometry data. The Generalised Linear Model (GLM with Negative Binomial (NB error structure was used to estimate the model parameters. Two types of models, the ‘core’ model which included key exposure variables only and the ‘full’ model which included a wider range of variables were developed. The results show that traffic flow, highway segment length, junction density, terrain type and presence of a village settlement within road segments were found to be statistically significant explanatory variables (p<0.05 for crash involvement. Adding one junction to a 1 km section of road segment was found to increase injury crashes by 32.0% and sections which had a village settlement within them were found to increase injury crashes by 60.3% compared with segments with no settlements. The model explained 61.2% of the systematic variation in the data. Road and Traffic Engineers and Planners can apply the crash prediction model as a tool in safety improvement works and in the design of safer roads. It is recommended that to improve safety, highways should be designed to by-pass village settlements and that the number of junctions on a highway should be limited to carefully designed ones.

Predicting crash-relevant violations at stop sign-controlled intersections for the development of an intersection driver assistance system.

Science.gov (United States)

Scanlon, John M; Sherony, Rini; Gabler, Hampton C

2016-09-01

Intersection crashes resulted in over 5,000 fatalities in the United States in 2014. Intersection Advanced Driver Assistance Systems (I-ADAS) are active safety systems that seek to help drivers safely traverse intersections. I-ADAS uses onboard sensors to detect oncoming vehicles and, in the event of an imminent crash, can either alert the driver or take autonomous evasive action. The objective of this study was to develop and evaluate a predictive model for detecting whether a stop sign violation was imminent. Passenger vehicle intersection approaches were extracted from a data set of typical driver behavior (100-Car Naturalistic Driving Study) and violations (event data recorders downloaded from real-world crashes) and were assigned weighting factors based on real-world frequency. A k-fold cross-validation procedure was then used to develop and evaluate 3 hypothetical stop sign warning algorithms (i.e., early, intermediate, and delayed) for detecting an impending violation during the intersection approach. Violation detection models were developed using logistic regression models that evaluate likelihood of a violation at various locations along the intersection approach. Two potential indicators of driver intent to stop-that is, required deceleration parameter (RDP) and brake application-were used to develop the predictive models. The earliest violation detection opportunity was then evaluated for each detection algorithm in order to (1) evaluate the violation detection accuracy and (2) compare braking demand versus maximum braking capabilities. A total of 38 violating and 658 nonviolating approaches were used in the analysis. All 3 algorithms were able to detect a violation at some point during the intersection approach. The early detection algorithm, as designed, was able to detect violations earlier than all other algorithms during the intersection approach but gave false alarms for 22.3% of approaches. In contrast, the delayed detection algorithm sacrificed

The roles of motorcyclists and car drivers in conspicuity-related motorcycle crashes.

NARCIS (Netherlands)

Craen, S. de Doumen, M. Bos, N. & Norden, Y. van

2012-01-01

This report gives an overview of the available research on the different factors of influence on the perception of motorcycles. It also presents analyses of Dutch motorcycle crashes which provide a description of the relative occurrence of car-motorcycle crashes in the Netherlands. Finally, this

Vital Sign Monitoring and Mobile Phone Usage Detection Using IR-UWB Radar for Intended Use in Car Crash Prevention

OpenAIRE

Seong Kyu Leem; Faheem Khan; Sung Ho Cho

2017-01-01

In order to avoid car crashes, active safety systems are becoming more and more important. Many crashes are caused due to driver drowsiness or mobile phone usage. Detecting the drowsiness of the driver is very important for the safety of a car. Monitoring of vital signs such as respiration rate and heart rate is important to determine the occurrence of driver drowsiness. In this paper, robust vital signs monitoring through impulse radio ultra-wideband (IR-UWB) radar is discussed. We propose a...

Self-harm and risk of motor vehicle crashes among young drivers : findings from the DRIVE Study

NARCIS (Netherlands)

Martiniuk, Alexandra L. C.; Ivers, Rebecca Q.; Glozier, Nick; Patton, George C.; Lam, Lawrence T.; Boufous, Soufiane; Senserrick, Teresa; Williamson, Ann; Stevenson, Mark; Norton, Robyn

2009-01-01

Background: Some motor vehicle crashes, particularly single-vehicle crashes, may result from intentional self-harm. We conducted a prospective cohort study to assess the risk that intentional self-harm poses for motor vehicle crashes among young drivers. Methods: We prospectively linked survey data

Risk Factors Associated with Crash Severity on Low-Volume Rural Roads in Denmark

DEFF Research Database (Denmark)

Prato, Carlo Giacomo; Rasmussen, Thomas Kjær; Kaplan, Sigal

2014-01-01

Safety on low-volume rural roads is drawing attention due to the high fatality and severe injury rates in comparison with high-volume roads and the increasing awareness of sustainable rural development among policy makers. This study analyzes the risk factors associated with crash severity on low......-volume rural roads, including crash characteristics, driver attributes and behavior, vehicle type, road features, environmental conditions, distance from the nearest hospital, and zone rurality degree. The data consist of a set of crashes occurred on low-volume rural roads in Denmark between 2007 and 2011...... advantage in accommodating the ordered-response nature of severity while relaxing the proportional odds assumption. Model estimates and pseudoelasticities show that aggravated crash injury severity is significantly associated with (1) alcohol and failure to wear seatbelts, (2) involvement of vulnerable road...

Macro-level safety analysis of pedestrian crashes in Shanghai, China.

Science.gov (United States)

Wang, Xuesong; Yang, Junguang; Lee, Chris; Ji, Zhuoran; You, Shikai

2016-11-01

Pedestrian safety has become one of the most important issues in the field of traffic safety. This study aims at investigating the association between pedestrian crash frequency and various predictor variables including roadway, socio-economic, and land-use features. The relationships were modeled using the data from 263 Traffic Analysis Zones (TAZs) within the urban area of Shanghai - the largest city in China. Since spatial correlation exists among the zonal-level data, Bayesian Conditional Autoregressive (CAR) models with seven different spatial weight features (i.e. (a) 0-1 first order, adjacency-based, (b) common boundary-length-based, (c) geometric centroid-distance-based, (d) crash-weighted centroid-distance-based, (e) land use type, adjacency-based, (f) land use intensity, adjacency-based, and (g) geometric centroid-distance-order) were developed to characterize the spatial correlations among TAZs. Model results indicated that the geometric centroid-distance-order spatial weight feature, which was introduced in macro-level safety analysis for the first time, outperformed all the other spatial weight features. Population was used as the surrogate for pedestrian exposure, and had a positive effect on pedestrian crashes. Other significant factors included length of major arterials, length of minor arterials, road density, average intersection spacing, percentage of 3-legged intersections, and area of TAZ. Pedestrian crashes were higher in TAZs with medium land use intensity than in TAZs with low and high land use intensity. Thus, higher priority should be given to TAZs with medium land use intensity to improve pedestrian safety. Overall, these findings can help transportation planners and managers understand the characteristics of pedestrian crashes and improve pedestrian safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

2010 traffic crash facts annual report

Science.gov (United States)

2010-01-01

The death rate on Nebraska roadways during 2010 was .97 persons killed per 100 million vehicle miles traveled. This is the lowest death rate recorded since the state first began keeping motor vehicle crash statistics in 1936. The trend of declining d...

Latent Classes of Polydrug Users as a Predictor of Crash Involvement and Alcohol Consumption.

Science.gov (United States)

Scherer, Michael; Romano, Eduardo; Voas, Robert; Taylor, Eileen

2018-05-01

Polydrug users have been shown to be at higher risk for alcohol consumption and crash involvement. However, research has shown that polydrug groups differ in some important ways. It is currently unknown how polydrug-using groups differ in terms of crash involvement and alcohol consumption. The current study used latent class analysis to examine subgroups of polydrug users (n = 384) among a sample of drivers in Virginia Beach, Virginia (N = 10,512). A series of logistic regression analyses were conducted to determine the relationship between polydrug use categories and crash involvement and alcohol consumption. Four distinct subclasses of users were identified among polydrug-using drivers: Class 1 is the "marijuana-amphetamines class" and accounts for 21.6% of polydrug users. Class 2 is the "benzo-antidepressant class" and accounts for 39.0% of polydrug users. Class 3 is the "opioid-benzo class" and accounts for 32.7% of polydrug users. Finally, Class 4 is the "marijuana-cocaine class" and accounts for 6.7% of the study sample. Drivers in the opioid-benzo class were significantly more likely than those in any other class as well as non-drug users and single-drug users to be involved in a crash and were more likely than those in most other conditions to consume alcohol. No significant difference was found between marijuana-amphetamine users or benzo-antidepressant users and non-drug users on crash risk. Some polydrug users are indeed at greater risk for crash involvement and alcohol consumption; however, not all polydrug users are significantly worse than single-drug users and/or non-drug users, and the practice of lumping polydrug users together when predicting crash risk runs the risk of inaccurately attributing crash involvement to certain drivers.

Development of a method to rate the primary safety of vehicles using linked New Zealand crash and vehicle licensing data.

Science.gov (United States)

Keall, Michael D; Newstead, Stuart

2016-01-01

Vehicle safety rating systems aim firstly to inform consumers about safe vehicle choices and, secondly, to encourage vehicle manufacturers to aspire to safer levels of vehicle performance. Primary rating systems (that measure the ability of a vehicle to assist the driver in avoiding crashes) have not been developed for a variety of reasons, mainly associated with the difficult task of disassociating driver behavior and vehicle exposure characteristics from the estimation of crash involvement risk specific to a given vehicle. The aim of the current study was to explore different approaches to primary safety estimation, identifying which approaches (if any) may be most valid and most practical, given typical data that may be available for producing ratings. Data analyzed consisted of crash data and motor vehicle registration data for the period 2003 to 2012: 21,643,864 observations (representing vehicle-years) and 135,578 crashed vehicles. Various logistic models were tested as a means to estimate primary safety: Conditional models (conditioning on the vehicle owner over all vehicles owned); full models not conditioned on the owner, with all available owner and vehicle data; reduced models with few variables; induced exposure models; and models that synthesised elements from the latter two models. It was found that excluding young drivers (aged 25 and under) from all primary safety estimates attenuated some high risks estimated for make/model combinations favored by young people. The conditional model had clear biases that made it unsuitable. Estimates from a reduced model based just on crash rates per year (but including an owner location variable) produced estimates that were generally similar to the full model, although there was more spread in the estimates. The best replication of the full model estimates was generated by a synthesis of the reduced model and an induced exposure model. This study compared approaches to estimating primary safety that could mimic

Taxonomy of Older Driver Behaviors and Crash Risk : with Appendices A and B

Science.gov (United States)

2012-02-01

This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...

Nonparametric Analyses of Log-Periodic Precursors to Financial Crashes

Science.gov (United States)

Zhou, Wei-Xing; Sornette, Didier

We apply two nonparametric methods to further test the hypothesis that log-periodicity characterizes the detrended price trajectory of large financial indices prior to financial crashes or strong corrections. The term "parametric" refers here to the use of the log-periodic power law formula to fit the data; in contrast, "nonparametric" refers to the use of general tools such as Fourier transform, and in the present case the Hilbert transform and the so-called (H, q)-analysis. The analysis using the (H, q)-derivative is applied to seven time series ending with the October 1987 crash, the October 1997 correction and the April 2000 crash of the Dow Jones Industrial Average (DJIA), the Standard & Poor 500 and Nasdaq indices. The Hilbert transform is applied to two detrended price time series in terms of the ln(tc-t) variable, where tc is the time of the crash. Taking all results together, we find strong evidence for a universal fundamental log-frequency f=1.02±0.05 corresponding to the scaling ratio λ=2.67±0.12. These values are in very good agreement with those obtained in earlier works with different parametric techniques. This note is extracted from a long unpublished report with 58 figures available at , which extensively describes the evidence we have accumulated on these seven time series, in particular by presenting all relevant details so that the reader can judge for himself or herself the validity and robustness of the results.

Fatal Cervical Spine Injury Following a Bicycle Crash

Directory of Open Access Journals (Sweden)

Uhrenholt Lars

2017-06-01

Full Text Available Spinal injury following direct loading of the head and neck is a rare sequel of bicycle crashes. Fatal head injuries following bicycle crashes have been described in great detail and safety measures such as bicycle helmets have been developed accordingly. Less frequently, however, potentially severe cervical spine injuries have been described. We present the case of a middle-aged female who sustained an ultimately fatal cervical spine injury following a collision with a car whilst biking wearing a helmet. We discuss the literature regarding the protective effects of bicycle helmets, the relevance to cervical spine injury and legislation on mandatory use of helmets for injury prevention.

Data development technical support document for the aircraft crash risk analysis methodology (ACRAM) standard

International Nuclear Information System (INIS)

Kimura, C.Y.; Glaser, R.E.; Mensing, R.W.; Lin, T.; Haley, T.A.; Barto, A.B.; Stutzke, M.A.

1996-01-01

The Aircraft Crash Risk Analysis Methodology (ACRAM) Panel has been formed by the US Department of Energy Office of Defense Programs (DOE/DP) for the purpose of developing a standard methodology for determining the risk from aircraft crashes onto DOE ground facilities. In order to accomplish this goal, the ACRAM panel has been divided into four teams, the data development team, the model evaluation team, the structural analysis team, and the consequence team. Each team, consisting of at least one member of the ACRAM plus additional DOE and DOE contractor personnel, specializes in the development of the methodology assigned to that team. This report documents the work performed by the data development team and provides the technical basis for the data used by the ACRAM Standard for determining the aircraft crash frequency. This report should be used to provide the generic data needed to calculate the aircraft crash frequency into the facility under consideration as part of the process for determining the aircraft crash risk to ground facilities as given by the DOE Standard Aircraft Crash Risk Assessment Methodology (ACRAM). Some broad guidance is presented on how to obtain the needed site-specific and facility specific data but this data is not provided by this document

Factors associated with pilot fatality in work-related aircraft crashes, Alaska, 1990-1999.

Science.gov (United States)

Bensyl, D M; Moran, K; Conway, G A

2001-12-01

Work-related aircraft crashes are the leading cause of occupational fatality in Alaska, with civilian pilots having the highest fatality rate (410/100,000/year). To identify factors affecting survivability, the authors examined work-related aircraft crashes that occurred in Alaska in the 1990s (1990-1999), comparing crashes with pilot fatalities to crashes in which the pilot survived. Using data from National Transportation Safety Board reports, the authors carried out logistic regression analysis with the following variables: age, flight experience, use of a shoulder restraint, weather conditions (visual flight vs. instrument flight), light conditions (daylight vs. darkness), type of aircraft (airplane vs. helicopter), postcrash fire, crash location (airport vs. elsewhere), and state of residence. In the main-effects model, significant associations were found between fatality and postcrash fire (adjusted odds ratio (AOR) = 6.43, 95% confidence interval (CI): 2.38, 17.37), poor weather (AOR = 4.11, 95% CI: 2.15, 7.87), and non-Alaska resident status (AOR = 2.10, 95% CI: 1.05, 4.20). Protective effects were seen for shoulder restraint use (AOR = 0.40, 95% CI: 0.21, 0.77) and daylight versus darkness (AOR = 0.50, 95% CI: 0.25, 0.99). The finding that state of residence was associated with survivability offers new information on pilot survivability in work-related aircraft crashes in Alaska. These results may be useful in targeting safety interventions for pilots who fly occupationally in Alaska or in similar environments.

Vehicle mass and injury risk in two-car crashes: A novel methodology.

Science.gov (United States)

Tolouei, Reza; Maher, Mike; Titheridge, Helena

2013-01-01

This paper introduces a novel methodology based on disaggregate analysis of two-car crash data to estimate the partial effects of mass, through the velocity change, on absolute driver injury risk in each of the vehicles involved in the crash when absolute injury risk is defined as the probability of injury when the vehicle is involved in a two-car crash. The novel aspect of the introduced methodology is in providing a solution to the issue of lack of data on the speed of vehicles prior to the crash, which is required to calculate the velocity change, as well as a solution to the issue of lack of information on non-injury two-car crashes in national accident data. These issues have often led to focussing on relative measures of injury risk that are not independent of risk in the colliding cars. Furthermore, the introduced methodology is used to investigate whether there is any effect of vehicle size above and beyond that of mass ratio, and whether there are any effects associated with the gender and age of the drivers. The methodology was used to analyse two-car crashes to investigate the partial effects of vehicle mass and size on absolute driver injury risk. The results confirmed that in a two-car collision, vehicle mass has a protective effect on its own driver injury risk and an aggressive effect on the driver injury risk of the colliding vehicle. The results also confirmed that there is a protective effect of vehicle size above and beyond that of vehicle mass for frontal and front to side collisions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of requirements and functional specifications for crash event data recorders : final report

Science.gov (United States)

2004-12-01

The U.S. DOT has conducted research on the requirements for a Crash Event Data Recorder to facilitate the reconstruction of commercial motor vehicle crashes. This report documents the work performed on the Development of Requirements and Functiona...

The impact of pedestal turbulence and electron inertia on edge-localized-mode crashes

Energy Technology Data Exchange (ETDEWEB)

Xi, P. W. [FSC and State Key Lab of Nuclear Physics and Technology, Department of Physics, Peking University, Beijing 100871 (China); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Xu, X. Q. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Center for Astrophysics and Space Sciences and Department of Physics, University of California San Diego, La Jolla, California 92093-0429 (United States)

2014-05-15

We demonstrate that the occurrence of Edge-Localized-Modes (ELM) crashes does not depend only on the linear peeling-ballooning threshold, but also relies on nonlinear processes. Wave-wave interaction constrains the growth time of a mode, thus inducing a shift in the criterion for triggering an ELM crash. An ELM crash requires the P-B growth rate to exceed a critical value γ>γ{sub c}, where γ{sub c} is set by 1/τ{sup ¯}{sub c}, and τ{sup ¯}{sub c} is the averaged mode phase coherence time. For 0<γ<γ{sub c}, P-B turbulence develops but drives enhanced turbulent transport. We also show that electron inertia dramatically changes the instability threshold when density is low. However, P-B turbulence alone cannot generate enough current transport to allow fast reconnection during an ELM crash.

Emerging interdependence between stock values during financial crashes.

Directory of Open Access Journals (Sweden)

Jacopo Rocchi

Full Text Available To identify emerging interdependencies between traded stocks we investigate the behavior of the stocks of FTSE 100 companies in the period 2000-2015, by looking at daily stock values. Exploiting the power of information theoretical measures to extract direct influences between multiple time series, we compute the information flow across stock values to identify several different regimes. While small information flows is detected in most of the period, a dramatically different situation occurs in the proximity of global financial crises, where stock values exhibit strong and substantial interdependence for a prolonged period. This behavior is consistent with what one would generally expect from a complex system near criticality in physical systems, showing the long lasting effects of crashes on stock markets.

Emerging interdependence between stock values during financial crashes.

Science.gov (United States)

Rocchi, Jacopo; Tsui, Enoch Yan Lok; Saad, David

2017-01-01

To identify emerging interdependencies between traded stocks we investigate the behavior of the stocks of FTSE 100 companies in the period 2000-2015, by looking at daily stock values. Exploiting the power of information theoretical measures to extract direct influences between multiple time series, we compute the information flow across stock values to identify several different regimes. While small information flows is detected in most of the period, a dramatically different situation occurs in the proximity of global financial crises, where stock values exhibit strong and substantial interdependence for a prolonged period. This behavior is consistent with what one would generally expect from a complex system near criticality in physical systems, showing the long lasting effects of crashes on stock markets.

The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

International Nuclear Information System (INIS)

Chen, Goong; Wang, Yi-Ching; Gu, Cong; Perronnet, Alain; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O

2017-01-01

Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics . This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

Science.gov (United States)

Chen, Goong; Wang, Yi-Ching; Perronnet, Alain; Gu, Cong; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O.

2017-03-01

Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics. This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

Patterns of injury seen in road crash victims in a South African ...

African Journals Online (AJOL)

Patterns of injury seen in road crash victims in a South African trauma centre. F Parkinson, S Kent, C Aldous, G Oosthuizen, DL Clarke. Abstract. Background. Road traffic crashes (RTCs) account for a significant burden of disease in South Africa. This prospective study reviews basic demographic and outcome data of ...

Light vehicle crash avoidance needs and countermeasure profiles for safety applications based on vehicle-to-vehicle communications

Science.gov (United States)

2013-04-30

This report discusses light-vehicle crash countermeasure profiles and functions for five target pre-crash scenario groups based on vehicle-to-vehicle (V2V) communications. Target pre-crash scenario groups include rear-end, lane change, opposite direc...