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1.
Crashes between pedestrians and motor vehicles are an important traffic safety concern. This paper explores the assignment of fault in such crashes, where observed factors are associated with pedestrian at fault, driver at fault, or both at fault. The analysis is based on police reported crash data for 1997 through 2000 in North Carolina, U.S.A.The results show that pedestrians are found at fault in 59% of the crashes, drivers in 32%, and both are found at fault in 9%. The results indicate drivers need to take greater notice of pedestrians when drivers are turning, merging, and backing up as these are some of the prime factors associated with the driver being found at fault in a crash.Pedestrians must apply greater caution when crossing streets, waiting to cross, and when walking along roads, as these are correlated with pedestrians being found at fault. The results suggest a need for campaigns focused on positively affecting pedestrian street-crossing behavior in combination with added jaywalking enforcement. The results also indicate that campaigns to increase the use of pedestrian visibility improvements at night can have a significant positive impact on traffic safety. Intoxication is a concern and the results show that it is not only driver intoxication that is affecting safety, but also pedestrian intoxication.The findings show in combination with other research in the field, that results from traffic safety studies are not necessarily transferable between distant geographic locations, and that location-specific safety research needs to take place. It is also important to further study the specific effects of the design of the pedestrian environment on safety, e.g. crosswalk spacing, signal timings, etc., which together may affect pedestrian safety and pedestrian behavior.  相似文献   

2.
Reconstruction of pedestrian–vehicle accident is a worldwide problem. Numerous previous studies have been carried out on accidents with vehicular skid marks or definite pedestrian throw distances. However, little could be done if marks or throw distances cannot be obtained in accident reconstruction. This paper first describes the physical model of dynamic process of pedestrian head impact on windshield glazing. Some simplifications are made to obtain a better and more practical model, including discussing the support boundary conditions. Firstly, the paper modeled the relations between pedestrian impact speed and deflection of windshield glazing based on the impact dynamics and thin plate theory. Later, the relations of vehicle impact speed and deflection are discussed. Therefore, a model of vehicle impact speed versus deflection of windshield glazing is developed. The model is then verified by ten real-world accident cases to demonstrate its accuracy and reliability. This model provides investigators a new method to reconstruct pedestrian–vehicle accidents.  相似文献   

3.
Walking is a popular form of physical activity associated with clear health benefits. Promoting safe walking for pedestrians requires evaluating the risk of pedestrian–motor vehicle collisions at specific roadway locations in order to identify where road improvements and other interventions may be needed. The objective of this analysis was to estimate the risk of pedestrian collisions at intersections and mid-blocks in Seattle, WA. The study used 2007–2013 pedestrian–motor vehicle collision data from police reports and detailed characteristics of the microenvironment and macroenvironment at intersection and mid-block locations. The primary outcome was the number of pedestrian–motor vehicle collisions over time at each location (incident rate ratio [IRR] and 95% confidence interval [95% CI]). Multilevel mixed effects Poisson models accounted for correlation within and between locations and census blocks over time. Analysis accounted for pedestrian and vehicle activity (e.g., residential density and road classification). In the final multivariable model, intersections with 4 segments or 5 or more segments had higher pedestrian collision rates compared to mid-blocks. Non-residential roads had significantly higher rates than residential roads, with principal arterials having the highest collision rate. The pedestrian collision rate was higher by 9% per 10 feet of street width. Locations with traffic signals had twice the collision rate of locations without a signal and those with marked crosswalks also had a higher rate. Locations with a marked crosswalk also had higher risk of collision. Locations with a one-way road or those with signs encouraging motorists to cede the right-of-way to pedestrians had fewer pedestrian collisions. Collision rates were higher in locations that encourage greater pedestrian activity (more bus use, more fast food restaurants, higher employment, residential, and population densities). Locations with higher intersection density had a lower rate of collisions as did those in areas with higher residential property values. The novel spatiotemporal approach used that integrates road/crossing characteristics with surrounding neighborhood characteristics should help city agencies better identify high-risk locations for further study and analysis. Improving roads and making them safer for pedestrians achieves the public health goals of reducing pedestrian collisions and promoting physical activity.  相似文献   

4.
The objectives of this research were to: (1) identify a more suitable model for modeling injury severity of motor vehicle drivers involved in train–motor vehicle crashes at highway–rail grade crossings from among three commonly used injury severity models and (2) to investigate factors associated with injury severity levels of motor vehicle drivers involved in train–motor vehicle crashes at such crossings. The 2009–2013 highway–rail grade crossing crash data and the national highway–rail crossing inventory data were combined to produce the analysis dataset. Four-year (2009–2012) data were used for model estimation while 2013 data were used for model validation. The three injury severity levels—fatal, injury and no injury—were based on the reported intensity of motor-vehicle drivers’ injuries at highway–rail grade crossings.  相似文献   

5.
Although past research has linked alcohol outlet density to higher rates of drinking and many related social problems, there is conflicting evidence of density's association with traffic crashes. An abundance of local alcohol outlets simultaneously encourages drinking and reduces driving distances required to obtain alcohol, leading to an indeterminate expected impact on alcohol-involved crash risk. This study separately investigates the effects of outlet density on (1) the risk of injury crashes relative to population and (2) the likelihood that any given crash is alcohol-involved, as indicated by police reports and single-vehicle nighttime status of crashes. Alcohol outlet density effects are estimated using Bayesian misalignment Poisson analyses of all California ZIP codes over the years 1999–2008. These misalignment models allow panel analysis of ZIP-code data despite frequent redefinition of postal-code boundaries, while also controlling for overdispersion and the effects of spatial autocorrelation. Because models control for overall retail density, estimated alcohol-outlet associations represent the extra effect of retail establishments selling alcohol. The results indicate a number of statistically well-supported associations between retail density and crash behavior, but the implied effects on crash risks are relatively small. Alcohol-serving restaurants have a greater impact on overall crash risks than on the likelihood that those crashes involve alcohol, whereas bars primarily affect the odds that crashes are alcohol-involved. Off-premise outlet density is negatively associated with risks of both crashes and alcohol involvement, while the presence of a tribal casino in a ZIP code is linked to higher odds of police-reported drinking involvement. Alcohol outlets in a given area are found to influence crash risks both locally and in adjacent ZIP codes, and significant spatial autocorrelation also suggests important relationships across geographical units. These results suggest that each type of alcohol outlet can have differing impacts on risks of crashing as well as the alcohol involvement of those crashes.  相似文献   

6.

Background

Motor vehicle crashes are the leading cause of maternal injury-related mortality during pregnancy in the United States, yet pregnant women remain an understudied population in motor vehicle safety research.

Methods

We estimated the risk of being a pregnant driver in a crash among 878,546 pregnant women, 16–46 years, who reached the 20th week of pregnancy in North Carolina (NC) from 2001 to 2008. We also examined the circumstances surrounding the crash events. Pregnant drivers in crashes were identified by probabilistic linkage of live birth and fetal death records and state motor vehicle crash reports.

Results

During the 8-year study period, the estimated risk of being a driver in a crash was 12.6 per 1000 pregnant women. Pregnant women at highest risk of being drivers in serious crashes were 18–24 years old (4.5 per 1000; 95% confidence interval, CI,4.3, 4.7), non-Hispanic black (4.8 per 1000; 95% CI = 4.5, 5.1), had high school diplomas only (4.5 per 1000; 95% CI = 4.2, 4.7) or some college (4.1 per 1000; 95% CI = 3.9, 4.4), were unmarried (4.7 per 1000; 95% CI = 4.4, 4.9), or tobacco users (4.5 per 1000; 95% CI = 4.1, 5.0). A high proportion of crashes occurred between 20 and 27 weeks of pregnancy (45%) and a lower proportion of crashes involved unbelted pregnant drivers (1%) or airbag deployment (10%). Forty percent of crashes resulted in driver injuries.

Conclusions

NC has a relatively high pregnant driver crash risk among the four U.S. states that have linked vital records and crash reports to examine pregnancy-associated crashes. Crash risks were especially elevated among pregnant women who were young, non-Hispanic black, unmarried, or used tobacco. Additional research is needed to quantify pregnant women's driving frequency and patterns.  相似文献   

7.
With the pressing demand of environmentally friendly personal transportation vehicles, mobility scooters become more and more popular for the short-distance transportation. Similar to pedestrians and bicyclists, scooter riders are vulnerable road users and are expected to receive severe injuries during traffic accidents. In this research, a MADYMO model of vehicle–scooter crash scenarios is numerically set up. The model of the vehicle with the scenario is validated in pedestrian–vehicle accident investigation with previous literatures in terms of throwing distance and HIC15 value. HIC15 values gained at systematic parametric studies. Injury information from various vehicle crashing speeds (i.e. from 10 m/s to 24 m/s), angles (i.e. from 0 to 360°), scooter's speeds (i.e. from 0 m/s to 4 m/s), contact positions (i.e. left, middle and right bumper positions) are extracted, analyzed and then compared with those from widely studied pedestrian–vehicle and bicycle–vehicle accidents. Results show that the ESS provides better impact protection for the riders. Riding ESS would not increase the risk higher than walking at the same impact conditions in terms of head injury. The responsible reasons should be the smaller friction coefficient between the wheel-road than the heel-road interactions, different body gestures leading to different contact positions, forces and timing. Results may shed lights upon the future research of mobility scooter safety analysis and also the safety design guidance for the scooters.  相似文献   

8.
There is growing concern that certain content within motor vehicle advertising may have a negative influence on driving attitudes and behaviours of viewers, particularly young people, and hence a negative impact on road safety. In response, many developed countries have adopted a self-regulatory approach to motor vehicle advertising. However, it appears that many motor vehicle advertisements in Australia and elsewhere are not compliant with self-regulatory codes. Using standard commercial advertising methods, we exposed three motor vehicle ads that had been the subject of complaints to the Australian Advertising Standards Board (ASB) to, N = 463, 14–55 year olds to assess the extent to which their perceptions of the content of the ads communicated themes that were contrary to the Australian self-regulatory code. All three ads were found to communicate messages contrary to the code (such as the vehicle's speed and acceleration capabilities). However, the ASB had upheld complaints about only one of the ads. Where motor vehicle advertising regulatory frameworks exist to guide motor vehicle advertisers as to what is and what is not acceptable in their advertising, greater efforts are needed to ensure compliance with these codes. One way may be to make it mandatory for advertisers to report consumer pre-testing of their advertising to ensure that undesirable messages are not being communicated to viewers.  相似文献   

9.
A novel application of age–period–cohort methods are used to explain changes in vehicle based crash rates in New South Wales, Australia over the period 2003–2010. Models are developed using vehicle age, crash period and vehicle cohort to explain changes in the rate of single vehicle driver fatalities and injuries in vehicles less than 13 years of age. Large declines in risk are associated with vehicle cohorts built after about 1996. The decline in risk appears to have accelerated to 12 percent per vehicle cohort year for cohorts since 2004. Within each cohort, the risk of crashing appears to be a minimum at two years of age and increases as the vehicle ages beyond this. Period effects (i.e., other road safety measures) between 2003 and 2010 appear to have contributed to declines of up to about two percent per annum to the driver-fatality single vehicle crash rate, and possibly only negligible improvements to the driver-injury single vehicle crash rate. Vehicle improvements appear to have been responsible for a decline in per-vehicle crash risk of at least three percent per calendar year for both severity levels over the same period. Given the decline in risk associated with more recent vehicle cohorts and the dynamics of fleet turnover, continued declines in per-vehicle crash risk over coming years are almost certain.  相似文献   

10.
The proportion of motor vehicle crashes that involve a drowsy driver likely is greater than existing crash databases reflect, due to the possibility that some drivers whose pre-crash state of attention was unknown may have been drowsy. This study estimated the proportion of crashes that involved a drowsy driver in a representative sample of 47,597 crashes in the United States from 1999 through 2008 that involved a passenger vehicle that was towed from the scene. Multiple imputation was used to address missing data on driver drowsiness. In the original (non-imputed) data, 3.9% of all crashes, 7.7% of non-fatal crashes that resulted in hospital admission, and 3.6% of fatal crashes involved a driver coded as drowsy; however, the drowsiness status of 45% of drivers was unknown. In the imputed data, an estimated 7.0% of all crashes (95% confidence interval: 4.6%, 9.3%), 13.1% of non-fatal crashes that resulted in hospital admission (95% confidence interval: 8.8%, 17.3%), and 16.5% of fatal crashes (95% confidence interval: 12.5%, 20.6%) involved a drowsy driver. Results suggest that the prevalence of fatal crashes that involve a drowsy driver is over 350% greater than has been reported previously.  相似文献   

11.

Background

Obesity is an epidemic in the United States. The relationship between traumatic injury and obesity in children is not well-studied. We hypothesized that overweight children suffer more severe injuries, different distributions of injuries and improper use of restraints in motor vehicle collisions.

Methods

We conducted a secondary analysis of the CIREN database of motor vehicle collisions of subjects 2-17 years old. Overweight was defined as a BMI percentile for age >85%. Significant injury was an Injury Severity Score (ISS) >15 or an Abbreviated Injury Scale (AIS) score greater than one. Further analysis looked at injuries classified as head, trunk, or extremities and appropriateness of restraints. Odds ratios compared the overweight to lean groups.

Results

335 subjects met inclusion criteria with 35.5% of cases being overweight. For significant injury, overweight cases had an odds ratio of 1.2 [95% CI: 0.8-1.9]. Analysis by AIS for overall significant injury and to specific body regions also did not show any significant associations. Overweight versus lean subjects had an odds ratio of 1.3 [95% CI: 0.8-2.1] for improper use of restraints.

Conclusions

We found no significant relationship between pediatric injury severity, distribution of injuries, or restraint use and being overweight. Limitations of this study were the small sample size in this database and the large number of unrestrained subjects.  相似文献   

12.
Based on data from the Web of Science, international collaboration between China and the UK in food and agriculture has been investigated from various perspectives. A new method for classifying cross- or multi-disciplinary fields has been created. The comparative study focuses on China’s collaboration with selected countries including the USA, the UK, Germany and Japan. The newly proposed Integrated Impact Indicator (I3) is applied to evaluate publication impact. Although China’s total publications dropped in 2010, its research productivity in food and agriculture nevertheless kept growing and international collaboration, reflected by the number of publications, also increased in an exponential way. The growth rate of China’s internationally collaborated publications was lower than that of China’s total publications. The USA, Japan, Canada, Australia, the UK and Germany are the top partners for Chinese researchers in this field. China-UK joint publications overall increased although their share in China’s total internationally collaborated publications decreased. To China, collaborating with the USA, the UK and Germany, instead of Japan, seems to offer an option to raise impact. The rapidly growing number of international publications and impact of Chinese research in food and agriculture offers great collaboration potential for the country. The fact that the average impact of China-UK collaborative publications is higher than the domestic publications of either country implies that collaboration benefits both sides as has been found in several other studies.  相似文献   

13.
Clean Technologies and Environmental Policy - This study investigates the impact of electric vehicle development on China’s greenhouse gas emissions and fossil energy consumption from a life...  相似文献   

14.
Effect of Al content on the stacking fault energy (SFE) was investigated in the austenitic Fe–25Mn–(1.16–9.77)Al–0.68C (at%) alloys by X-ray diffraction line profile analysis and thermodynamic estimation, and was discussed on the basis of anomaly in shear modulus caused by the antiferromagnetic transition. The experimental results show that the stacking fault probability decreases with increasing Al content, the observed SFE increases linearly when Al content is lower than 6.27 at%, and markedly as it is more than 6.27 at%. The thermodynamic estimation indicates that the non-magnetic component of SFE increases faster than the observed one with increasing Al content in the antiferromagnetic state, and both are almost equal in the paramagnetic state. The magnetic order increases SFE in the antiferromagnetic state, and the magnetic component of SFE depends on the average magnetic moment and Néel temperature. The increases in the localized magnetic moment and the decrease in the Néel temperature are caused by the addition of Al atoms into the austenitic Fe–Mn alloys and are accompanied by the anomaly in shear modulus, which affects SFE in the antiferromagnetic state. The anomalous drop in shear modulus leads to the inconsistency for the variations of the observed SFE and non-magnetic component with Al content in the antiferromagnetic state.  相似文献   

15.
Ruimin Ma 《Scientometrics》2012,93(3):645-659
The intellectual structure and its evolution of library and information science (LIS) in China are analyzed with time series data from Chinese Social Sciences Citation Index which is the properest database for ACA practice in the field of social science at present. The result indicates that the subfields of Library and Information Science in China kept changing from 1998 to 2007: some subfields have emerged and developed a lot, e.g., webometrics and competitive intelligence; some subfields maintain, e.g., bibliometrics and intellectual property; and some subfields have begun to decline, e.g., cataloging. Through the comparison with the international LIS, it is found that there are some unique subfields in Chinese LIS from 1998 to 2007, such as competitive intelligence and intellectual property. At the same time, I also suggest that Chinese authors in LIS should pay more attention to the applied research in the future.  相似文献   

16.
China’s economy and technology have experienced spectacular growth since the Opening-up Policy adopted in 1978. In order to explore the innovation process and development of China, this study examines the inventive activities and the collaboration pattern of university, industry and government (UIG) in China. This study analyzes the Chinese patent data retrieved from the United States Patent and Trademark Office. Three models of UIG relations which represent different triple helix configurations are introduced. According to the property of patent assignee, patent ownership can be divided into three types: individuals, enterprises, and universities and research institutes. Furthermore, enterprises can be classified into state-owned enterprise (SOE), private-owned enterprise (POE) and foreign enterprise (FE). The corresponding relationship of patent ownership with UIG is set up. Through analyzing the issued year, it is found that the inventive activities of China have experienced three developmental phases and have been promoted quickly in recent years. The achievement of innovation activities in China primarily falls on the enterprise, especially FEs and POEs. The innovation strengths of the three development phases have shifted from government to university and research institute and then industry. According to co-patent analysis, it is found that the collaboration between university and industry is the strongest and has been intensified in recent years, but other forms of collaboration among UIG have been weak. In addition, an innovation relation model of China was set up. The evolution process of innovation systems was explored, from etatistic model, followed by improved “laissez-faire” model, and then shifting toward triple helix model.  相似文献   

17.
To improve the low work hardening capacity of Hadfield steel at low stress, the effect of stacking fault energy (SFE) on the microstructures and the work hardening behaviors of the Fe–Mn–Si–C high manganese steels were investigated by varying the silicon and carbon contents. The work hardening rates of the Fe–17Mn–Si–C steels with lower SFE were higher than that of the Hadfield steel at the strain below 0.28. The reason was that the amount of deformation-induced ε-martensite or mechanical twins was higher in the Fe–17Mn–Si–C steels than in the Hadfield steel due to their earlier onset. The work hardening rate of the Fe–17Mn–Si–C steels increased with decreasing the SFE because the rate of the formation and the amounts of martensite and twins increased with lowering the SFE.  相似文献   

18.
The efficiency of transmissions is related directly to the energy consumption in vehicle systems. Hence, it is worth a lot researching the overall power losses inside the transmission, in order to modify the transmission performance or optimize the transmission. In most research works, only how to model the component power losses is considered. It is then necessary to put forward a general or standard method to calculate the overall power losses in the transmissions. In this paper, a general model of overall power losses in transmissions is built up, based on the selection of the submodels of component power losses from literature. With the help of the experimental data from the test bench, the methodology of parameter identification is introduced. As a result, more accurate power loss distribution of the transmission is possible to be obtained, through combining the overall efficiency experimental data and the model of overall power losses. In order to validate the methodology, it is applied into two study cases of different transmissions. Through the results of the two study cases, it is concluded that the methodology of modelling of power losses in transmissions with parameter identification is ready to be extended to other transmission study cases. It is expected that with the help of the methodology in this paper, a platform can be built up to benchmark different production transmissions in the future.  相似文献   

19.
20.
The media continues to be a prominent and widely embraced channel for obtaining information on various topics, exerting considerable influence in shaping public opinions. This holds particularly true for the realm of automated vehicles (AVs), as the media consistently covers developments in this field, encompassing both positive aspects such as technological advancements, as well as negative occurrences like incidents involving self-driving cars colliding with pedestrians. The objective of this study was to utilize sentiment analysis techniques to evaluate the portrayal of AV technology in media news coverage. Data was retrieved from Sprinklr using keywords that are often associated with AVs. Over 1.7 million articles were collected on the keywords for relevant articles published between May 1, 2015 to May 24, 2021. Sentiment analysis was carried out on the cleaned data using three different models – VADER, TextBlob, and NRCLex. The sentiment analysis was separately conducted on the title and text of the articles. 2018 recorded the highest number of news articles on the AV technology. The number of negative sentiments in the title of articles published on the web in 2018 increased 12 times compared to the previous year. The negativity induced in 2018 in the news media did not continue in the next year, which explains that the technology experienced short term effects from the negative incidents associated with its early development. The news articles were also found to have subjectivity from the authors in the article text. The findings are expected to stimulate debates among industry players on how to bring the media along the journey of the development and eventual full deployment of AVs.  相似文献   

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