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671.
ProblemAutomobile crashes are one of the leading causes of death in the United States, especially for younger and older drivers. Additionally, distracted driving is another leading factor in the likelihood of crashes. However, there is little understanding about the interaction between age and secondary task engagement and how that impacts crash likelihood and maneuver safety.MethodData from the Naturalistic Driving Study (NDS), which was part of the Second Strategic Highway Research Program (SHRP2), were used to investigate this issue.ResultsIt was found that the distribution of crashes per one million km driven during the NDS was similar to previous research, but with fewer crashes from older drivers. Additionally, it was found that older and middle-aged drivers engaged in distracted driving more frequently than was expected, and that crashes were significantly more likely if drivers of those age groups were engaged in secondary tasks. However, secondary task engagement did not predict judgment of safe/unsafe vehicle maneuvers.Practical ApplicationsMore research is needed to better understand the interaction of age and distraction on crash likelihood. However, this research could aid future researchers in understanding the likelihood of future use of new in-vehicle technologies for different age groups, as well as provide insight to the engagement patterns of distraction for different age groups.  相似文献   
672.
Introduction: Rear-end crashes are one of the most frequent crash types in China, leading to significant economic and societal losses. The development of active safety systems – such as Automatic Emergency Braking System (AEBS) – could avoid or mitigate the consequences of these crashes in Chinese traffic situations. However, a clear understanding of the crash causation mechanisms is necessary for the design of these systems. Method: Manually coded variables were extracted from a naturalistic driving study conducted with commercial vehicles in Shanghai. Quantitative analyses of rear-end crashes and near crashes (CNC) were conducted to assess the prevalence, duration, and location of drivers’ off-path glances, the influence of lead vehicle brake lights on drivers’ last off-path glance, and driver brake onset, and the influence of off-path glances and kinematic criticality on drivers’ response to conflicts. Results: The results indicate that the Chinese truck drivers in our study rarely engage in distracting activities involving a phone or other handheld objects while driving. Instead, they direct their off-path glances mainly toward the mirrors, and the duration of off-path glances leading to critical situations are shorter compared to earlier analyses performed in Western countries. The drivers also often keep small margins. Conclusions: Overall, the combination of short time headway with off-path glances directed toward the mirror originates visual mismatches which, associated to a rapid change in the kinematic situation, cause the occurrence of rear-end CNC. When drivers look back toward the road after an off-path glance, a fast response seems to be triggered by lower values of looming compared to previous studies, possibly because of the short time headways. Practical Application: The results have practical implications for the development of driver models, for the design of active safety systems and automated driving, and for the design of campaigns promoting safe driving.  相似文献   
673.
Introduction: Studies have shown that approximately half of arrested intoxicated drivers had their last alcoholic drink at a licensed bar or restaurant. Current efforts to prevent intoxicated patrons from leaving licensed establishments and driving home have been only partially successful. Since a high proportion of drinkers drive to their drinking destination, promoting the use of alternative transportation (AT) – including safe ride shuttles, free or subsidized taxi and ridesharing services, voluntary or paid designated driver programs, and more accessible public transportation – is an important strategy for preventing impaired driving. The primary goal of this study was to review and synthesize the findings of research studies designed to test the effectiveness of AT programs in reducing alcohol-impaired driving. A secondary goal was to report if using AT has led to any unintended consequences, in particular greater alcohol consumption. Method: We identified relevant academic articles, new articles, government reports, and other documents (English only) through the University of Chicago library, Google Scholar, and Google Search. We also included published articles recommended by peers. Key search terms included: alternative transportation; safe rides; designated driver; alcohol-impaired driving; alcohol consumption, cost effectiveness; and reduce drunk driving. Initially, we identified 168 potentially relevant sources, of which only 57 were academic articles. After a thorough review, we narrowed down the number of relevant articles to 125 including some background articles and government reports. Results: Some AT programs produced reductions in one or more of the following outcomes: (1) impaired driving; (2) impaired driving crashes; (3) driving under the influence (DUI) arrests; and (4) traffic crashes in general, but others were not shown to be effective. A few programs resulted in greater self-reported alcohol use, but there were no significant findings indicating that drinking when using AT led to an increase in alcohol-related harms such as public intoxication, assaults, or other alcohol-related crime. Of the studies that conducted a cost-benefit analysis, most showed that AT programs yielded a positive benefit, but these studies did not include a sufficient number of variables to be considered true cost-benefit analyses. Conclusions: There is mixed evidence regarding the effectiveness of AT programs. Evaluations with more rigorous quasi-experimental and experimental designs are needed to identify which types of AT programs work best for different types of communities and target groups. Practical Applications: The literature review and synthesis revealed that the most successful AT programs typically have some of these attributes: (1) social acceptance; (2) high level of public awareness; (3) low cost; (4) year-round availability; (5) provide rides to and from drinking venues; (6) several sponsors that provide funding); (7) user convenience; and (8) perceived safety.  相似文献   
674.
山东省耕地资源总量虽在近几年相对增加,但总体仍呈下降趋势,且人均耕地面积下降速度更快,耕地资源状况不容乐观。目前全省各地市耕地总量变化的动态平衡程度不一,德州市是耕地资源动态平衡相对最好的地市,其次为青岛、枣庄和泰安市,莱芜市耕地资源动态平衡状况较差。利用主成分分析方法的计算结果表明,经济活动、社会人口和农业科技发展水平等因素为影响山东省耕地数量变化的主要驱动因子;在以上研究的基础上,预测了山东省人口承载力和2010年粮食短缺情况。  相似文献   
675.
INTRODUCTION: There is evidence suggesting that the problem of fatigued or drowsy driving is an important contributor to road crashes. However, not much is known about public perceptions of the issue. The purpose of this study was to obtain information on attitudes, opinions, and professed practices related to fatigued or drowsy driving. METHODS: The data were gathered by means of a public opinion poll among a representative sample of 750 Ontario drivers. RESULTS: A majority of drivers (58.6%) admitted that they occasionally drive while fatigued or drowsy. Of greater importance, 14.5% of respondents admitted that they had fallen asleep or "nodded off" while driving during the past year. Nearly 2% were involved in a fatigue or drowsy driving related crash in the past year. Respondents were also asked about measures they take to overcome fatigue or drowsiness. Results indicate that relatively ineffective measures such as opening the window or playing music are the most popular; the most effective preventive measure--taking a rest--is the least popular. DISCUSSION: The prevalence of the behavior, coupled with the ineffective prevention measures favored by the public suggest there is a need for increasing their level of awareness and knowledge about the problem. IMPACT ON INDUSTRY: Results from this study further emphasize the importance of increasing the fatigued and drowsy driving knowledge base and the need to educate the public about it.  相似文献   
676.
INTRODUCTION: Aggressive driving encompasses a continuum of behaviors that range from extreme acts, such as shootings, to less severe manifestations, such as arguments and gestures. It is clear from the available data that aggressive driving is not uncommon and very risky. However, little is known about the opinions and practices of drivers. The purpose of this study was to help bridge these gaps. METHODS: The data were gathered by means of a public opinion poll among a representative sample of 1,201 Canadian drivers. Univariate frequency distributions and 95% confidence intervals were calculated and logistic regression and generalized linear latent models were used to summarize the data. RESULTS: It was found that the issue of aggressive driving is a significant one as a considerable percentage of drivers admits to it. The results coming from the logistic regression and the generalized linear latent model suggest that male and younger drivers are more likely to behave aggressively in traffic and that behaving more aggressively is associated with a history of traffic tickets. DISCUSSION: When gauging people's attitudes, opinions, and behaviors, it becomes clear that aggressive driving is a considerable problem. There also seems to be a need for a better understanding of which specific behaviors respondents associate with the generic term "aggressive driving." IMPACT ON INDUSTRY: Results from this study further emphasize the need of increasing the aggressive driving knowledge base.  相似文献   
677.
Sixteen and 17 year-olds were surveyed at motor-vehicle offices in Tennessee after qualifying for their first driver's license. When the survey was conducted during October and November 1995, neither a learner's permit nor completion of a driver education course was required to obtain a license at age 16 or 17. The survey was repeated during December and January 1996–97, approximately one year after a requirement to hold a learner's permit for 90 days or complete a driver education course was implemented. Results from the 1991 drivers (ages 16 and 17) surveyed indicated Tennessee's licensing law change was associated with approximately 100 additional miles and 8 additional hours of practice driving prior to licensure for the typical 16 or 17 year-old, most often while supervised by a parent or guardian. Results are discussed in relation to the prelicense practice driving requirements of graduated licensing systems.  相似文献   
678.
驾驶行为理论模型研究概述   总被引:4,自引:4,他引:0  
通过回顾驾驶行为的研究概况,重点介绍了4种理论模型:计划行为理论、威慑理论、事故原因模型、情境中介模型。在此基础上,分析了我国驾驶行为研究现状,并提出开展我国驾驶行为研究的初步建议和未来的研究方向:发展适用于我国的驾驶行为模型,并进一步研究在我国文化背景和道路环境下,不安全驾驶行为与示范性规范、文化因素以及情境变量等因素之间的关系,从心理学角度减少不安全驾驶行为和事故卷入,改善交通安全,提高交通效率。  相似文献   
679.
企业是践行可持续理念、实现可持续发展目标的重要主体。企业需要在生产经营过程中统筹提升环境(E)、社会(S)、治理(G)三个维度的ESG绩效。基于外部压力和内部实力,本文预先设定了国家背景、行业属性、金融实力三种因素驱动企业改善ESG绩效的理论假设。为检验假设,本文使用多元线性回归和多层线性模型对来自55个国家、共计6139家上市公司样本进行实证研究。结果表明,即使在控制企业规模、风险管理和社会声誉的情况下,国家可持续发展水平、行业绿色发展水平、企业金融实力仍能显著提升企业ESG绩效。其中,国家和行业变量不仅直接促进了企业ESG绩效的提升,还在更高维度上通过调节CFP-ESG的关系间接促进企业ESG绩效的提升。本研究有助于企业更好地制定实施可持续发展战略,也能为投资者评估并筛选出ESG绩效优异的企业提供科学参考。  相似文献   
680.
对蒸汽驱采废水回用高压锅炉给水处理工艺进行了研究,并对比分析了不同的工艺组合流程对蒸汽驱采废水回用高压锅炉给水的处理效果。结果表明,蒸汽驱采废水回用高压锅炉给水处理在技术上是可行的,并提出推荐工艺流程。  相似文献   
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