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761.
Objectives: Pedestrian crashes are a critical problem in Latin American countries. However, little research has been published about pedestrians and even less about their behaviors in a naturalistic context. The objective of the present research was to explore risky pedestrian crossing behaviors in traffic intersections in an argentine city (Ushuaia). It is focused in different stages of the crossing process, traffic code violations, and other potentially risky behaviors such as distractions. A high frequency of risky behaviors among pedestrians was expected. Moreover, according to previous findings, it was hypothesized that men and younger pedestrians would show riskier behaviors.

Methods: Participants were 802 pedestrians (53.9% females) observed at several intersections (with and without traffic lights) in the city of Ushuaia. Behaviors were codified following a standardized observation protocol. Observers documented information on behavior previous to, during, and after crossing. Gender and age were also registered. Data were gathered through video recording. Frequency analyses of observed behaviors were conducted for the total sample, as well as by gender and by age group. A general crossing risk index was calculated to facilitate comparisons between the genders and age groups. We conducted an analysis of variance to evaluate gender and age differences for this index.

Results: A high proportion of risky behaviors were observed among pedestrians. The majority of pedestrian waited in the street (as opposed to on the sidewalk) before crossing, did not comply with traffic lights, or crossed outside the crosswalk. A large number of pedestrians were distracted while crossing. Men presented higher scores on risky behaviors than women. No differences were observed by age group.

Conclusions: The high level of risk behaviors during the different stages of street crossing is worrisome and reinforces the idea that pedestrians are responsible for many of the conflicts with motorists. Many of the risky behaviors seem to be associated with gender, which is in line with the previous literature showing more risk behaviors among men than among women. No differences were found for age group. Findings are interpreted considering some features of the Argentine road culture.  相似文献   

762.
Objective: A child safety restraint (CSR) is an effective measure to reduce the risk of child injury from traffic collisions. This study aims to explore knowledge, attitudes, and behaviors regarding CSRs in a Chinese population.

Methods: A cross-sectional survey regarding CSR use was conducted from April to May 2014 in Shenzhen municipality. Respondents were parents who had at least one child 0 to 6 years of age and owned a car. These parents provided a self-report of demographic characteristics as well as information about their knowledge, attitudes, and behaviors toward CSR use.

Results: Most respondents had a fair level of knowledge about CSRs, with higher mean knowledge scores demonstrated among the respondents who were male, had an advanced degree, had a higher income, owned an expensive car, had an older child, drove frequently with children, and routinely drove greater distances with children. In addition, most respondents had a more positive attitude toward CSR use, with a higher mean attitude score among those who had an advanced degree, owned an expensive car, drove frequently with children, and routinely drove greater distances with children. However, some myths regarding CSR use also existed (e.g., parents can effectively protect their children in a car collision by holding them, they are not required to purchase the CSR for child safety if there is no mandatory provision by law, among others). Among 3,768 respondents who had at least one child and a car, 27.8% (1,047) had a CSR and 22.9% (864) used the CSR. A logistic regression model showed the likelihood of CSR ownership to be higher if respondents drove frequently or greater distances and was dependent on both the education level of the respondents and the age of the children. The frequency of CSR use increased as the age of children decreased (P = .0274). Respondents who owned a CSR and those who frequently used CSRs had higher mean knowledge and mean attitude scores.

Conclusions: This observational study found that although the majority of respondents had fair levels of knowledge and positive attitudes, they had lower rates of CSR ownership and use. Therefore, efforts at developing opportunities to expand public awareness of CSR use should be made to improve child passenger safety practices and eliminate child injury caused by traffic collisions.  相似文献   

763.
Objective: Driving speed is a major concern for driving safety under reduced visibility conditions. Many factors affect speed selection in low visibility, but few studies have been conducted examining drivers' characteristics, particularly in China. The present study aimed to investigate the correlation between drivers' demographic information, driving ability, and speed choice in low-visibility conditions using a sample of Chinese drivers.

Methods: A self-designed driving ability scale was used to assess driving ability in reduced visibility conditions. The reliability and validity of 306 gathered questionnaires were examined in this article, and a structural equation model (SEM) was built to explore the predictors of drivers' speed selection behavior under reduced visibility conditions and to measure the relationships between various factors.

Results: Age and driving experience have no direct relationship to speed selection behavior in reduced visibility, but the frequency of using expressways and annual mileage are significantly related to the speed on roads that have a speed restriction of 80 or 120 km/h. Under reduced visibility conditions, driving ability has a significant effect on speed selection behavior, and driving skill (DS) is the most influential on speed selection behavior on roads with a speed limit of 120 km/h; otherwise, the effect of risk perception (RP) does not differ by speed choice on 3 roads with different speed limits. Driving speed in good weather also has a positive influence on speed selection behavior in low visibility.

Conclusion: Driving ability is directly associated with speed selection in reduced visibility conditions, and some demographic data indirectly influence speed selection. This study provides useful recommendations for drivers' training programs to reduce casualties from accidents in low-visibility conditions.  相似文献   

764.
为明晰行为安全管理研究与实践的基本框架,从而为行为安全管理提供新的思路、依据和方法,针对已有行为安全模型存在的缺陷,对行为安全管理元模型开展构造与演绎研究。首先,直接从安全行为本体出发,结合心理学与行为科学相关知识,构造行为安全管理元模型;其次,详细剖析行为安全管理元模型的基本内涵,并扼要概述行为安全管理元模型的应用价值。研究结果表明:行为安全管理元模型的主体部分,是组织系统之中安全行为主体相关安全行为的产生及作用过程,可阐明行为安全管理研究实践的基本程式与框架,促进行为安全管理研究与实践。  相似文献   
765.
从2013年到2016年我国大气污染防治所取得的巨大成就不能用来说明2015年修订通过的《大气污染防治法》为防治大气污染发挥了巨大的作用。那些成就主要是由以《重点区域大气污染防治"十二五"规划》《大气污染防治行动计划》为标志的政府防治大气污染的行动取得的。《大气污染防治法》(2015)的加"严"修订主要表现在:罚则条款数量增加;违法行为种类增加;责任类型增多;多处设定"惩罚束";设定阶梯式处罚;创设身份罚新形式,多处设定机能罚等方面。那些加"严"修订都服务于实现"行为人不违反"这个规制目标。以往的研究成果表明,使"行为人不违反"的法律不能保证使环境达到一定的质量目标。近年我国政府环境保护举措取得成功的秘诀主要有三点,即:(1)减少绝对排放量;(2)政府负责,而不是行政相对人负责;(3)用权力推行,而不是用设惩罚"威胁"行政相使之守法的方式寻求大气污染防治目标的实现。要让大气污染防治法成为我国防治大气污染的基本依据和有效防治大气污染的保障,必须对新修订的《大气污染防治法》再行修订。新的修订应当以政府的大气污染防治行为为着力点。这样的修订主要应当考虑:建立大气质量目标制度;健全总行为控制制度;按照大气污染防治的需要明确对各级政府、地方权力机关的授权;规定政府或其职能部门的职责和相关行政权运行的约束程序。在对《大气污染防治法》实施了以"政府的大气污染防治行为"为着重点的修改之后,国家将取得法治国家建设和大气污染防治法制建设的双重收获。  相似文献   
766.
In this study, we characterize the greatest sediment loading events by their sediment delivery behavior; dominant climate, watershed, and antecedent conditions; and their seasonal distribution for rural and urban land uses. The study area is Paradise Creek Watershed, a mixed land use watershed in northern Idaho dominated by saturation excess processes in the upstream rural area and infiltration excess in the downstream urban area. We analyzed 12 years of continuous streamflow, precipitation, and watershed data at two monitoring stations. We identified 137 sediment loading events in the upstream rural section of the watershed and 191 events in the downstream urban section. During the majority of these events conditions were transport limited and the sediment flush occurred early in the event, generally in the first 20% of elapsed event time. Statistical analysis including two dozen explanatory variables showed peak discharge, event duration, and antecedent baseflow explained most of the variation in event sediment load at both stations and for the watershed as a whole (R2 = 0.73‐0.78). In the rural area, saturated soils combined with spring snowmelt in March led to the greatest loading events. The urban area load contribution peaked in January, which could be a re‐suspension of streambed sediments from the previous water year. Throughout the study period, one event contributed, on average, 33% of the annual sediment load but only accounted for 2% of the time in a year.  相似文献   
767.
对氮气中聚乙烯在不同温度、不同载气流量以及铁、镍、铜三种金属影响下的裂变行为研究结果表明,温度、氮气流量以及三种金属对聚乙烯的裂变有重要影响.在300、500、700℃三个温度条件下,链烃(包括饱和链烃和不饱和链烃)是裂变产物的主体,未发现有多环芳烃形成.在900℃时形成少量低环的多环芳烃.在1100℃和1200℃条件下,不同环数的多环芳烃(单环至五环)及同分异构体是裂变产物的主体,链烃(包括饱和链烃和不饱和链烃)的生成量与前期温度相比有较大幅度的减少.在金属铁、镍、铜分别存在的条件下,聚乙烯的裂变及多环芳烃的形成受到了不同程度的影响.氮气流量的增加有利于降低多环芳烃的形成.  相似文献   
768.
为回顾和总结新中国70年来的不安全行为研究,推动具有中国特色的安全行为管理理论研究,基于新中国70年国内员工不安全行为领域的564篇文献,运用文献计量与Citespace知识图谱分析工具,分析我国员工不安全行为研究成长规律,构建作者和研究机构共现图谱,识别出该领域主要作者、机构及其合作网络特征.研究结果表明:我国员工不...  相似文献   
769.
Many prey assess predation risk through predator chemical cues. Numerous studies have shown that (1) prey sometimes respond to chemical cues produced by heterospecifics and (2) that many species are capable of associative learning. This study extends this research by focusing on predation risk assessment and antipredator behavior in environments containing chemical cues produced by multiple prey species. The results show that green frog (Rana clamitans) tadpoles (1) assess risk from the chemical cue produced during predation by a heterospecific (gray tree frog, Hyla versicolor, tadpoles) and (2) can exhibit similarly strong behavioral responses to a mix of conspecific and heterospecific cues compared to conspecific cue alone, depending on their conditioning environment. I then discuss how the prey choice of the predators and the relative abundances of the prey species should influence the informational value of heterospecific cues.  相似文献   
770.
The regulation of protein collection through pollen foraging plays an important role in pollination and in the life of bee colonies that adjust their foraging to natural variation in pollen protein quality and temporal availability. Bumble bees occupy a wide range of habitats from the Nearctic to the Tropics in which they play an important role as pollinators. However, little is known about how a bumble bee colony regulates pollen collection. We manipulated protein quality and colony pollen stores in lab-reared colonies of the native North American bumble bee, Bombus impatiens. We debut evidence that bumble bee colony foraging levels and pollen storage behavior are tuned to the protein quality (range tested: 17–30% protein by dry mass) of pollen collected by foragers and to the amount of stored pollen inside the colony. Pollen foraging levels (number of bees exiting the nest) significantly increased by 55%, and the frequency with which foragers stored pollen in pots significantly increased by 233% for pollen with higher compared to lower protein quality. The number of foragers exiting the nest significantly decreased (by 28%) when we added one pollen load equivalent each 5 min to already high intranidal pollen stores. In addition, pollen odor pumped into the nest is sufficient to increase the number of exiting foragers by 27%. Foragers directly inspected pollen pots at a constant rate over 24 h, presumably to assess pollen levels. Thus, pollen stores can act as an information center regulating colony-level foraging according to pollen protein quality and colony need. An erratum to this article can be found at  相似文献   
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