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81.
PROBLEM: Although graduated driver licensing (GDL) programs have reduced the high crash rates for 16-and 17-year-old drivers, research suggests that some teenagers fail to comply with restrictions on nighttime driving and carrying passengers. METHOD: A program to encourage compliance with GDL restrictions and seat belt requirements was implemented in Guilford County, North Carolina. The program combined increased enforcement with a multi-faceted publicity campaign drawing attention to the enforcement activity. A comparison community was studied to assess whether changes over time could be reasonably attributed to the program. RESULTS: Several measures indicate that greater enforcement did occur in the intervention community and that teenagers perceived the increase. However, self-reported data and direct observations of young drivers in the intervention and comparison communities showed the program resulted in only modest changes in compliance with GDL restrictions. DISCUSSION: The program put in place the mechanisms known to produce changes in driver behavior, but these may have been insufficient to alter the behavior of the minority of teenagers (and parents) who were not already complying with restrictions. However, the modest changes in young driver behavior plus the clear changes in both actual and perceived enforcement suggest that high visibility enforcement programs merit further use and evaluation in other communities, particularly those where compliance with GDL provisions is lower than in Guilford County.  相似文献   
82.
83.
PROBLEM: The purpose of this study is to understand the reasons behind older women's driving cessation by comparing the driving histories of Finnish women who either gave up or renewed their drivers license at the age of 70. METHOD: A mail survey was sent to all Finnish women born in 1927 who gave up their license in 1997 (N=1,476) and to a corresponding random sample of women who renewed their license (N=1,494). The total response rate was 42.1%. RESULTS: The length and level of activity of personal driving history were strongly associated with driving cessation and continuation. Ex-drivers tended to have an inactive driving career behind them, whereas drivers had a more active personal driving history. In addition, those women with an active, "male-like" driving history who had decided to stop driving gave reasons for driving cessation that were similar to what is known about older men's reasons to give up driving. The results suggest that the decision to stop driving is related to driving habits rather than gender.  相似文献   
84.
PROBLEM: Young drivers, particularly those who are newly licensed, have a very high crash risk. This paper examines the risk factors underlying their high crash rates and assesses the extent to which existing graduated licensing programs address these risks and whether improvements to these programs should be considered. METHOD: Review and synthesis of the literature. RESULTS: The elevated risk among young drivers of being in an injury crash is the result of a number of factors found alone or in combination, such as risky driving, alcohol use, seat belt nonuse, driver distraction, fatigue, and vehicle choice. Nighttime and passenger restrictions, adopted widely in the United States, work by keeping drivers out of hazardous situations rather than by addressing risk factors directly. However, the risk factors remain in play in driving situations not specifically restricted by law. Although other graduated licensing components adopted around the world-more stringent exit tests (i.e., you need to pass a test to move to the next stage), hazard perception tests, and restrictions on speed, vehicle power, and roadway access-make sense based on the identified risk factors, they are not yet supported by research. Should research findings warrant it, consideration should be given to providing guidance to parents about how to keep their beginning drivers safe, including information on vehicle choice. IMPACT ON RESEARCH, PRACTICE, AND POLICY: Researchers should continue to monitor and to evaluate innovative approaches to reduce the crash risk of young drivers. The effectiveness of new approaches should be established before adoption on a wider scale takes place.  相似文献   
85.
该文收集有关城市的1959~1979年逐年的晴天太阳辐射资料,根据辐射传输方程扣除水汽和CO2的吸收效应,利用各地区污染物浓度垂直分布和混合层高度规律,再同已有的TSP监测资料分区分析,可得到有关地区的大气TSP质量的逐年反演值。   相似文献   
86.
Objective: A number of training programs that seek to improve driving performance among older drivers are available accompanied by a growing interest in their effectiveness. The purpose of the present investigation was to examine the combined effect of (1) basic in-class training (BT); (2) on-road training with individualized feedback (OR); and (3) training on a driving simulator (S).

Methods: Using a randomized controlled trial study design, 78 older drivers were randomly assigned to one of 3 groups (BT, BT + OR, or BT + OR + S). All participants completed a pre- and postintervention on-road driving evaluation on a standardized route. The driving evaluations were recorded using video and Global Positioning System (GPS) equipment and were scored by a blind assessor.

Results: The results indicated a significant reduction of approximately 30% in overall number of driving errors/omissions among participants in the BT + OR and the BT + OR + S groups in comparison to participants in the BT group.

Conclusions: This study adds to the mounting evidence demonstrating the effectiveness of individualized driver training in improving safe driving among older adults.  相似文献   

87.
Abstract

Objective: Recently developed advanced driver assistance systems (ADAS) have the potential to compensate for teen driving errors and reduce overall crash risk. To date, very limited research has been conducted on the suitability of ADAS for teen drivers—the population most likely to benefit from such systems. The opportunity for ADAS to reduce the frequency and severity of crashes involving teen drivers is hindered when there is a lack of trust, acceptance, and use of those technologies. Therefore, there is a need to study teen and parent perceptions of ADAS to help identify and overcome any potential barriers to ADAS use.

Methods: A U.S. national survey was developed based on themes from previously conducted teen and parent ADAS focus groups. Survey topics included trust in ADAS, effect of ADAS on teen driver safety and driving behavior, effect of ADAS on skill development, data privacy, and cybersecurity. Responses included 5-point Likert scales and open-ended questions. The survey was managed through an online respondent panel by ResearchNow. Eligibility criteria included licensed teens (16–19 years) and parents of licensed teens. Teen and parent responses were compared using chi-square statistics in SAS 9.4.

Results: Two thousand and three (teens?=?1,000; parents?=?1,003) respondents qualified for and completed the survey between September 1 and September 20, 2017. Overall, teens (72%) and parents (61%) felt that ADAS would have a positive impact on transportation. However, teens were more likely to exhibit a positive outlook on ADAS, whereas parents were more likely to have a negative outlook (P?<?.01). Teens felt that ADAS would be useful during bad weather or drowsy driving but were less concerned than parents about ADAS intervention during their own risky driving (P?<?.01). The majority of teens (65%) and parents (71%) agreed that teens should learn to drive on vehicles without ADAS, with parents being more likely to agree than teens (P?<?.01). Parents (55%) were more likely than teens (47%) to be concerned about insurance companies keeping track of teen driving data (P?<?.01). Most respondents exhibited some concern of ADAS being susceptible to hacking (57%).

Conclusions: This study represents the first effort to quantify ADAS perceptions among teen drivers and their parents at the U.S. national level. These data highlight potential barriers to ADAS use among teen drivers, including a relative disinterest among teens for ADAS intervention during risky driving as well as concerns among both teens and parents that ADAS will inhibit skill development. These survey findings will help inform educational programs to accelerate fleet turnover and provide the foundation for ADAS optimization and evaluation studies among sociodemographic groups.  相似文献   
88.
为了进一步提升高速铁路司机的安全绩效,保证高速铁路的运输安全,以高速铁路司机为研究对象,利用国内11家铁路局的调研数据,构建理论模型,实证研究家长式领导风格对安全氛围及安全行为的影响,采用回归分析和Bootstrap技术进行检验。结果表明:德行领导、仁慈领导和威权领导均对高速铁路司机的安全行为产生显著正向影响;安全氛围在家长式领导风格与安全行为之间起到部分中介作用;德行领导和仁慈领导对安全行为具有正向交互影响效应。  相似文献   
89.
为进一步了解机车乘务员睡眠状况及影响因素,以更好改善职工睡眠状况、为保证行车安全提供依据。采用阿森斯失眠量表及睡眠呼吸障碍问卷等心理测量法,选取某铁路局集团公司864名机车乘务员开展相关调研。结果表明,机车乘务员睡眠问题较严重,有失眠和可疑失眠的机车乘务员合计占调查人员总数的96.5%;睡眠问题主要表现为睡不好和睡觉中打呼噜,分别占调查中有失眠问题机车乘务员总数的86.7%和65.3%;工作环境和工作压力大导致的睡眠问题是机车乘务员失眠的主要原因,体重指数超标与患阻塞性睡眠呼吸暂停风险的机车乘务员占有失眠问题人员总数比例较高。进而提出加大睡眠健康宣传、降低职工体重指数及患阻塞性睡眠呼吸暂停的风险、改善机车乘务员工作环境、提高职工自我心理调节能力等改善职工睡眠质量的建议。  相似文献   
90.
In glacierized catchments, elevation is correlated with meltwater through its association with temperature, precipitation, and glacier hypsometry. The revelation of the altitudinal distribution of meltwater, unattended and not fully understood in previous work, might provide a better understanding of climate change impacts on glacio‐hydrology. Here, critical zone approach was defined and applied in 12 glacierized catchments of the Tien Shan–Pamir–Karakorum Mountains, Central Asia using manually calibrated glacier‐enhanced Soil and Water Assessment Tool model over 1966–2005. The critical zone, a sequence of elevation bands with above‐average snow and glacier melt, contributes maximum meltwater to total runoff. The critical zone shared 37%–95% (average = 80%) of meltwater contributions to total runoff, although its size was only 13%–30% of the total elevational relief. The critical zone controlled 76% and 82% variability in relative changes of glacier area and total runoff at the catchment scale, respectively. The increase in temperature was identified as the dominant driver for variations in total runoff in all catchments except Vakhsh and Yurungkash, where precipitation change remained dominant. Overall, glacier hypsometry limited the first‐order control of meltwater distributions on glacio‐hydrology. It is concluded that critical zone approach can interpret the proxy role of elevation to affect water availability under climate and glacier area change in glacierized catchments.  相似文献   
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