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971.
Introduction: The growth of the European market for road-freight transport has recently led to important changes. The growing number of foreign pavilion drivers transiting in France, which plays a bridging role among European countries, has influenced the lives of truck drivers by increasing competition, pressure on day-to-day activities, and constraints related to delivery deadlines. Adding this new pressure to those inherent in the road-freight transport sector has raised concerns, especially ones linked to levels of perceived stress by truck drivers. Method: With safety concerns in mind, we devised a questionnaire aimed at understanding how French truck drivers and non-French truck drivers, passing through four highway rest areas in France perceive stress, organizational factors, mental health, and risky driving behaviors. A sample of 515 truck drivers took part in the survey (260 French nationals), 97.9% of whom were male. Results: The results of a structural equation model indicated that perceived stress can increase self-reported risky driving behaviors among truck drivers. Furthermore, organizational factors and mental health were closely linked to perceived stress. Finally, some differences were found between French and non-French truck drivers with respect to mind-wandering and mental health, and to perceive driving difficulties to overcome and driving skills. Practical Applications: Several recommendations based on the findings are provided to policymakers and organizations. 相似文献
972.
Introduction: This research systematically reviewed relevant studies on users’ acceptance of conditional (Level 3) to full (Level 5) automated vehicles when such vehicles are to be used privately (herein referred to as ‘private automated vehicles or private AVs). Method: The search followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, and was undertaken in three databases: APA PsycINFO, Transport Research International Documentation, and Web of Science. Articles were required to focus on individuals’ acceptance of private SAE Level 3–5 AVs. Acceptance was defined as individuals’ attitudes towards or intentions and/or willingness to use AVs in the future. A total of 2,354 articles were identified in the database search. Thirty-five articles were included in the review, six of which included multiple studies and/or comparison groups. Results: Most studies (n = 31) applied self-reported measures to assess user acceptance together with a range of psychosocial factors predicting such acceptance. The meta-analytic correlations revealed that perceived behavioral control, perceived benefits/usefulness, perceived ease of use, and subjective/social norms had significant positive pooled relationships with attitudes and intentions. Trust and sensation seeking also had significant positive pooled correlations with intentions, while knowledge of AVs had a significant and negative pooled correlation with intentions. Age did not show any significant pooled relationship with attitudes, intentions, or willingness. Conclusions: The findings obtained from the systematic review and meta-analysis provide support for psychosocial models to aid understanding of users’ acceptance of private AVs. Practical applications: Examining acceptance of AVs after participants have experienced these vehicles on closed tracks or open roads would advance contemporary knowledge of users’ intentions to use these vehicles in the future. Further, experiencing these vehicles firsthand may also help with addressing any perceived barriers reducing acceptance of future use of private AVs. 相似文献
973.
974.
为有效提高水雾综合除尘性能,基于水雾捕尘过程及抑尘作用机理,从复合抑尘剂润湿、吸湿、黏结作用组分出发,讨论不同性质粉尘与抑尘剂各组分间匹配协同关系,进而研究复合型水雾抑尘剂优选方法。结果表明:湿润组分优选疏水端含有碳碳双键、醚基或链间存在氢键的表面活性剂;通过改变疏水基链长、不饱和度和支链数等方法,使湿润组分亲水、亲油性与粉尘相匹配。吸湿组分优选体心立方晶胞结构、溶解度相对较小的无机盐或混合配方无机盐,或者含极性强、能形成氢键的基团且空间结构复杂的有机吸湿剂。黏结组分优选溶液黏度高、交联网状、结构复杂的高分子聚合物。在上述组分优选的基础上,通过抑尘剂复配性能实验合理确定各组分的最优配比。 相似文献
975.
Major accidents have catastrophic effects on humans and all of society. To prevent the occurrence of major accidents, it is essential to strengthen the management of major hazard installations. Generally, effective identification and reasonable evaluation of major hazard installations are the basic steps in safety management. At present, the evaluation methods for major hazard installations mainly focus on consequence analysis and probabilistic analysis without considering the vulnerability of hazard-affected bodies. Therefore, the proposed method will introduce regional disaster system theory and comprehensively analyze hazard-formative factors, the hazard-formative environment and hazard-affected bodies to achieve a more complete and effective assessment of major hazard installations. Hazard-formative factors are evaluated based on the rapid ranking method, hazard-formative environments are evaluated based on Bayesian networks, and hazard-affected bodies are evaluated based on the fuzzy comprehensive evaluation method. A tank group and a chemical industrial park are used to verify the feasibility and effectiveness of the new method. 相似文献
976.
罗通元 《中国安全生产科学技术》2021,17(8):177-182
为厘清安全科学的本质问题,探究系统科学思维下的安全基本定义和学科体系。以刘潜安全定义和“3要素4因素”系统原理为基础,探讨其科学逻辑。通过文献调研阐述主流安全定义,分析人类安全认识历史,在此基础上分析和解释刘潜安全定义及其内涵。基于刘潜安全定义的内涵,推断出其具有的4大外延,同时提出刘潜安全定义的特征。根据科学哲学、系统科学和科学学的基础理论,刘潜建立安全“3要素4因素”系统原理,对系统原理的内涵进行阐述。最后,分析刘潜安全定义的科学价值。结果表明:刘潜安全定义能够为安全科学奠定系统性、科学性和共性的认识基础,在安全基础概念中起到引领作用。 相似文献
977.
贵州烟区生态条件及烤烟质量状况分析 总被引:26,自引:0,他引:26
以贵州烟区气候、土壤等生态因素和烤烟外观、物理、化学及感官质量的数据资料为基础,分析了该区9大植烟区域生态条件及烟叶质量状况.结果表明,贵州烟区海拔高度差异悬殊,具有大田期气温适宜,降雨充沛,日照充足,空气相对湿度高等特点.植烟土壤pH值适宜,有机质含量丰富,具有较强的保肥能力;氮素、磷素含量适中,钾素则难以满足烟株需求;土壤交换性钙、镁比值适宜,有效硫含量较高;多数微量元素含量丰富.但有效硼和水溶性氯含量缺乏.烟叶外观质量较好,香型以中间香型和偏清香型为主,香味的亲和力好.燃烧性强,配伍性高,但物理特性和化学成分间的协调性与国外优质烟区相比尚有差距. 相似文献
978.
亚洲地区稻田N2O排放影响因子统计模拟分析 总被引:2,自引:2,他引:0
关于稻田N2O排放大样本统计分析大多只涉及水分因子和肥料因子,本研究收集历年亚洲稻田N2O排放资料和更多影响因子(水分管理、肥料类型及用量、土壤属性、气候和水稻类型等)的相关信息,从中筛选出具有统计学意义的因子,构建排放通量和上述因子的统计模型.具有统计学意义的因子包括不同水分管理措施、肥料用量、不同有机肥类型、不同p... 相似文献
979.
The concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in two plant species (Scirpus tripueter Linn. and Cyperus malaccensis Lam.), water, and soils sampled from the reclaimed tidal riparian wetlands (RTRWs) and the natural riparian wetlands (NRWs) in the Pearl River estuary (PRE), were analyzed to investigate and compare their distribution and accumulation. The results show that the concentrations of the six studied heavy metals in soils exceed the eco-toxic threshold recommended by USEPA. The concentrations of Cd, Cr, and Zn in plants may lead to toxic effects compared to others.The hydraulic conditions and the degree of human disturbances can affect the heavy metal accumulation in RTRWs and NRWs. The heavy metal concentrations in water are higher whereas they are lower in soils of RTRWs Compared with that in the NRWs. The accumulation of heavy metals in the roots of plants is higher in NRWs than those in RTRWs while the opposite result is found for heavy metal accumulation in shoots. Based on the bioaccumulation and translocation factors, the plants in NRWs have the higher capacity to accumulate heavy metals, while higher abilities to transport heavy metals from roots to shoots are observed in RTRWs. Heavy metal contaminations in RTRWs are dominated by anthropogenic sources from both side uplands and river water, whereas in NRWs, the metal accumulations are simultaneously affected by anthropogenic and natural factors. 相似文献
980.