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561.
Objective: The adaptive behavior of mobile phone–distracted drivers has been a topic of much discussion in the recent literature. Both simulator and naturalistic studies suggest that distracted drivers generally select lower driving speeds; however, speed adaptation is not observed among all drivers, and the mechanisms of speed selection are not well understood. The aim of this research was to apply a driver behavioral adaptation model to investigate the speed adaptation of mobile phone–distracted drivers.

Methods: The speed selection behavior of drivers was observed in 3 phone conditions including baseline (no conversation) and hands-free and handheld phone conversations in a high-fidelity driving simulator. Speed adaptation in each phone condition was modeled as a function of secondary task demand and self-reported personal/psychological characteristics with a system of seemingly unrelated equations (SURE) accounting for potential correlations due to repeated measures experiment design.

Results: Speed adaptation is similar between hands-free and handheld phone conditions, but the predictors of speed adaptation vary across the phone conditions. Though perceived workload of secondary task demand, self-efficacy, attitude toward safety, and driver demographics were significant predictors of speed adaptation in the handheld condition, drivers' familiarity with the hands-free interface, attitude toward safety, and sensation seeking were significant predictors in the hands-free condition. Drivers who reported more positive safety attitudes selected lower driving speeds while using phones.

Conclusion: This research confirmed that behavioral adaptation models are suitable for explaining speed adaptation of mobile phone distracted drivers, and future research could be focused on further theoretical refinement.  相似文献   

562.
运用系统决策方法优选大气污染治理方案   总被引:2,自引:0,他引:2  
本文运用层次分析和多目标决策技术来量化大气污染治理方案的综合效益,从而为最佳治理方案的选取提供了科学依据.  相似文献   
563.
After copulation, male Nannophya pygmaea dragonflies mate guard by hovering over ovipositing females and repelling conspecific males. Copulation is not always a prerequisite for oviposition in the females of this species because females can store the sperm received during previous visits/copulations. An oviposition episode consists of several bouts of oviposition separated by periods of perching. We conducted two types of male-removal experiments to examine the effects of mating and post-copulatory mate guarding on the oviposition behaviour of females. In the first experiment, we removed all males from the habitat to eliminate the effect of re-copulation, mate-guarding and harassment by males. In the second experiment, we removed males immediately after copulation to eliminate the effects of guarding and other post-copulatory male-female interactions. We compared these experimental data with data obtained under natural conditions. The dipping rate in an oviposition bout was not influenced by copulation or guarding. However, guarded females made more dips per episode than did solitary females. The proportion of time actually spent ovipositing (total bout duration/oviposition episode duration) of guarded females was higher than that of solitary females. Solitary females often oviposited in more than one territorial site, while guarded females usually oviposited within a single territorial site during an oviposition episode. Because males tend to hold territories at sites where egg survival is high, guarded females (and the male guardian) benefit from guarding in terms of egg hatchability. The possible benefits for solitary females are discussed.  相似文献   
564.
关于风景评价中心理物理学方法局限性的探讨   总被引:5,自引:1,他引:5  
由于对西方风景评价理论和方法缺乏足够的了解和深入的研究,现今国内对其中的心理物理学方法及其作用产生了一些误解。本文在扼要介绍了心理物理学派的主要方法思路之后,着重对该学派所存在的重大理论缺陷和方法局限性做了较深入的分析。  相似文献   
565.
对产品开发中的绿色技术进行了研究分析 ,从技术的审核、技术的选择、技术的过渡以及技术的创新等方面提出了相应的问题和解决方法 ,并对有关内容建立了分析模型  相似文献   
566.
从生活污水中分离得到一株在强碱性条件下能絮凝天然碱碱泥的高效絮凝剂产生菌EWY1,并通过稳定性试验证明了其具有较好的稳定性,经鉴定为肠球菌属(Enterococcus)中的盲肠肠球菌(E.cecorum).通过单因素试验和正交试验确定了该菌产絮凝剂的最佳培养基为:麦芽糖15 g·L-1,KNO3 1.2 g·L-1,KH2PO4 0.5 g·L-1,MgSO4·7H2O 0.4 g·L-1,NaCl0.6 g·L-1,FeSO4·7H2O 0.008 g·L-1;该菌产絮凝剂的最佳培养条件为pH 7.0、温度30℃、摇床转速170 r·min-1.絮凝实验结果表明,用该菌产生的絮凝剂处理天然碱碱泥效果较好,絮凝率达到了89%.  相似文献   
567.
污染几率原则用于近岸海域大气采样点的选位   总被引:1,自引:0,他引:1  
应用污染几率原则,选择在沿岸地区最大污染几率的上风方位设方大气采样点,通过实验分析并与盛行风,污染风原则选位结果比较表明,该原则具有显著实用性。  相似文献   
568.
In order to provide a basis for international discussion of ethics among geneticists, we surveyed the responses of medical geneticists to a questionnaire describing 14 hypothetical cases that posed ethical dilemmas. The cases were selected through discussions with leading geneticists in 12 nations, as representative of the most difficult problems of moral choice experienced in practice. Six cases involved indications for prenatal diagnosis or disclosure of information. All medical geneticists in each of 18 nations were included. Of 1053 asked to participate, 677 (64 per cent) responded. A large majority (83 per cent) would perform prenatal diagnosis for parents who oppose abortion but request the service. A smaller majority (63 per cent) would do so for maternal anxiety, and a minority (25 per cent) would perform for sex selection in the absence of X-linked disease. Most would disclose conflicting controversial, or ambiguous test results, and two-thirds would disclose colleagues' differences of opinion.  相似文献   
569.
宝山高速公路路域草本植物选择   总被引:1,自引:0,他引:1  
刘孔杰  刘龙  张玉珍 《交通环保》2001,22(5):19-20,36
以宝山高速公路路域为实验点,从草本植物的生物习性和公路路域的特点出发筛选适于该地区及周边地区公路路域的草本植物,方法包括野生植物的调查筛选,外来物种的引进和筛选,经过2年的实施,筛选出若干适于宝山公路及华大部分地区公路路域的草本植物。  相似文献   
570.
以某污水厂的氧化沟污泥和剩余污泥为培养对象,获得了SRB占优的厌氧污泥,分析了活性污泥厌氧驯化过程中微生物的分布规律,考察了不同种类SRB污泥固定化小球处理水中硫酸根、锌及镉的效果.结果表明:pH6.0~7.0,温度35℃,硫酸盐浓度4g/L,时间在24h时,剩余污泥固定化小球处理含Zn(II)400mg/L的废水,去除率达到100%,氧化沟污泥固定化小球Zn(II)的去除率为90%左右;对500mg/L含镉废水,剩余污泥固定化小球8h能去除水中95?(II),氧化沟污泥固定化小球对Cd(II)的去除率为80%.硫酸盐还原菌污泥固定化技术中剩余污泥优于氧化沟污泥.  相似文献   
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