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481.
In road safety, it may be debated whether all risky behaviors are sufficiently similar to be explained by similar factors. The often assumed generalizability of the factors that influence risky driving behaviors has been inadequately tested. Study 1 (N=116) examined the role of demographic, personality and attitudinal factors in the prediction of a range of risky driving behaviors, for young drivers. Results illustrated that different driving behaviors were predicted by different factors (e.g., speeding was predicted by authority--rebellion, while drink driving was predicted by sensation seeking and optimism bias). Study 2 (N=127) examined the generalizability of these results to the general driving population. Study 1 results did not generalize. Predictive factors remained behavior-specific, but different predictor-behavior relationships were observed in the community sample. Overall, results suggest that future research and practice should focus on a multi-factor framework for specific risky driving behaviors, rather than assuming generalizability across behaviors and driving populations.  相似文献   
482.
Motor-vehicle crash rates are highly elevated immediately after licensure and then decline gradually over a period of years. Young age, risk taking, and inexperience contribute to the problem, but inexperience is particularly important early on. Driving is like other complex, skilled behaviors in which subtle improvements in perception and judgment develop gradually over a period of years. After all, safe driving is more a matter of attention and perception than physical management of the vehicle. Inexperience is particularly linked to driving performance and safety outcomes under certain driving conditions, with driving at night and with teen passengers as the most important cases. Surprisingly, driving outcomes do not appear to be affected by the pre-license training or supervised practice driving. Given the limits of training, safety effects can best be achieved by countermeasures that delay licensure or limit novice teen driving under high risk driving conditions while novices gain experience and develop safety competence. The two complementary approaches of Graduated Driver Licensing policies and parent management have been shown to provide safety effects by limiting the driving conditions of novice teenagers.  相似文献   
483.
PROBLEM: The implementation of Graduated Driver Licensing (GDL) programs has significantly improved the crash and fatality rates of novice teen drivers, but these rates remain unacceptably high. METHOD: A review of adolescent development research was undertaken to identify potential areas of improvement. RESULTS: Research support for GDL was found to be strong, particularly regarding early acquisition of expertise in driving safety (beyond driving skill), and to limitations that reduce opportunities for distraction. GDL regimes are highly variable, and no US jurisdictions have implemented optimal regimes. SUMMARY: Expanding and improving GDL to enhance acquisition of expertise and self-regulation are indicated for implementation and for applied research. Driver training that effectively incorporates safety goals along with driving skill is another target. IMPACT ON INDUSTRY: The insurance industry will benefit from further GDL enhancements. Benefits may accrue to improved driver training, improved simulation devices during training, and automated safety feedback instrumentation.  相似文献   
484.
INTRODUCTION: The purpose of this investigation was to identify risky driving behaviors and dispositions that distinguish drivers who use a cell phone while operating a motor vehicle from non-cell phone using drivers. METHOD: Annual telephone surveys were used to identify drivers who reported using a cell phone while driving in the last month (n=1803) and were compared to those who said they did not use cell phones while driving (n=1578). RESULTS: Cell phone using drivers were more likely to report driving while drowsy, going 20 mph over the speed limit, driving aggressively, running a stop sign or red light, and driving after having had several drinks. They were also more likely to have had a prior history of citation and crash involvement than non-cell phone using drivers. Cell phone using drivers also reported they were less careful and more in a hurry when they drive than non-cell phone using drivers. CONCLUSION: Cell phone using drivers report engaging in many behaviors that place them at risk for a traffic crash, independent of the specific driving impairments that cell phone usage may produce. Strategies that combine coordinated and sustained enforcement activities along with widespread public awareness campaigns hold promise as effective countermeasures for these drivers, who resemble aggressive drivers in many respects.  相似文献   
485.
池州市2000—2010年能源足迹动态测度与驱动因子分析   总被引:3,自引:1,他引:2  
能源足迹测度分析是揭示能源消费对区域环境压力及可持续发展的重要方法.基于能源足迹的碳吸收计量模型、能源足迹强度与生态压力分析方法,利用统计年鉴中能源消费数据,对2000—2010年池州能源足迹及生态压力与强度进行了动态测度,运用灰色GM(1,1)预测模型,对2015年、2020年能源足迹进行了预测,并借鉴STIRPAT模型对能源足迹驱动因子进行了分析.结果表明:池州人均能源足迹由2000年的0.1173ghm2(全球公顷,下同)上升至2010年的0.8993ghm2,呈波动上升趋势.2000—2003年,人均能源足迹的供给大于需求,EPIEF<1,2004年开始人均能源足迹的需求已超过供给,供需状态严重失衡,EPIEF>1,2010年,EPIEF比值达2.4,能源足迹为森林对能源足迹承载力的2.41倍.煤炭足迹为能源足迹的主要贡献者,平均贡献率达90.21%.能源足迹强度整体呈倒"U"型趋势.人口规模、人均GDP、第二产业在经济中所占比例、单位工业增加值能耗与能源足迹呈正相关关系,边际弹性系数分别为0.5698、0.590、1.468、0.144.可为池州市政府动态了解能源消费对环境形成的压力,准确把握可持续发展状况,进而为制定相应的发展策略提供科学依据,也可为微观尺度区域能源足迹研究提供借鉴.  相似文献   
486.
重型柴油车道路循环工况下排放特性的仿真分析   总被引:1,自引:0,他引:1  
柴油车道路工况下NOx排放和排温的动态特性对柴油机排气后处理系统的工作以及后处理系统控制策略的确定具有重要的影响.根据6114涡轮增压柴油机的万有特性及NOx和排温的MAP图,仿真分析了道路循环工况下配有6114柴油机的重型柴油车的NOx排放和排温的动态变化;研究了道路工况、行驶特征、驾驶行为以及柴油车载荷等对柴油车排放的影响规律.研究结果表明,城市道路循环工况下,柴油车NOx排放的整体水平不高,但变化频繁、剧烈;高速公路道路循环工况下,柴油车NOx排放整体水平较高,但变化平缓;加速过程,尤其是在高速区对柴油车排放的影响显著;冲动的驾驶方式会显著提高柴油车的排放水平;满载时,柴油车的高排放区将由半载时的高速高加速区向外扩展至其他工况点,高排放区显著增大.  相似文献   
487.
长江经济带城市土地利用效率格局演变及驱动机制研究   总被引:5,自引:0,他引:5  
以长江经济带为研究区域,综合运用DEA模型、ESDA统计指数及Tobit线性回归模型等方法对长江经济带城市土地利用效率格局演变及驱动机制进行了初步地分析。结果表明:(1)2000~2012年长江经济带城市土地利用效率总体上呈上升趋势,存在显著区域差异,且技术效率高于综合效率和规模效率;(2)全局上城市土地利用效率呈现出正的空间自相关,效率高(低)的城市相互空间邻接;局部上城市土地利用效率的L-L类型主要集中在川西高原区,空间分布形态较平稳,而效率H-H类型主要分布在上海及苏南地区,并逐渐向绍杭、皖江地区演化,从"一字形"转向"Z字形"分布;(3)城镇化、经济发展、产业结构、科技水平及土地市场化是研究期长江经济带城市土地利用效率格局时空演变主要驱动力。  相似文献   
488.
运用水足迹理论和计算方法,系统分析了四川省各市(州)2003~2011年农业水足迹的时空动态变化趋势与农业水资源利用效益,并采用灰色关联度法分析其驱动力因素。研究结果表明:(1)四川省各市(州)农业水足迹和人均农业水足迹均呈增加的趋势变化,成都市、南充市、达州市农业水足迹较大,2011年农业水足迹分别达82.44×108,45.56×108,41.02×108 m3。人均农业水足迹各市(州)差距不大,其中成都市和攀枝花市略高。(2)农业水资源利用效益方面显示:四川省各市(州)农业水足迹净贸易量均为正值,属于农业水资源净输出地。2006、2009、2010和2011年农业水资源匮乏度较高,成都市水资源紧缺度最高,2005~2010年均在200%以上。(3)驱动因素方面显示:耕地复种指数和人口总数是农业水足迹变化的关键驱动因素,关联度分别是0.643 3和0.632 5。建议提高水资源利用效益,适当控制高耗水农产品生产规模,合理配置水资源,实现空间和季节用水的协调性。  相似文献   
489.
研究驾驶过程中随着疲劳的产生驾驶员生理信号的变化规律,提取反映驾驶疲劳程度的综合指标。采用驾驶模拟器对20名被试进行驾驶模拟试验,用MP150多导生理仪实时采集并记录驾驶员在60 min驾驶任务过程中的心电信号、脑电信号、肌肉电阻信号、皮肤温度信号和呼吸频率信号。运用R软件对数据进行线性回归分析,对比一般回归分析,逐步线性回归分析克服了一般回归分析许多变量不显著的缺点,得到了最优的驾驶综合指标方程,确定了与各项指标相关的驾驶疲劳评价综合指标,并通过3名被试模拟驾驶试验验证了综合指标作为评价驾驶疲劳的有效性。  相似文献   
490.
分心驾驶容易影响驾驶行为,进而导致交通事故的问题。用理论建模方法,研究分心对驾驶行为及其可靠性的影响。介绍分心驾驶的定义和维度。基于驾驶行为理论,建立融合分心维度的驾驶行为模型,分析不同分心维度对驾驶行为的影响机理。基于可靠性理论,建立融合分心维度的驾驶行为可靠性模型,分析不同分心维度对驾驶行为可靠性的影响。结果表明:不同维度分心对驾驶行为的影响具有各自特点和交互性;减少影响系数高的分心维度,有助于提高驾驶行为可靠性;多维度分心比单维度分心会更大程度地降低驾驶行为可靠度,应减少或避免复合分心。  相似文献   
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