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91.
92.
采用Daniel趋势检验法对哈尔滨市近年来SO2、NO2和PM10年均浓度变化趋势分析,并对城市总人口与经济、产业结构、民用汽车保有量和能源状况五个城市发展因素进行数据统计分析,用SPSS探究城市发展过程中影响大气污染的因素及相关性.结果表明:浓度变化趋势是SO2明显上升;NO2缓慢上升;PM10整体明显下降,但在2013年点突增至了0.119 mg/m3.SO2与NO2显著相关,相关系数为0.533.经统计,哈尔滨人口经济发展、产业结构调整较为缓慢,全市民用汽车保有量增加并未对NO2浓度影响显著,能源结构依然以煤为主,虽然能源强度提升,但也存在着煤质、散煤的问题.哈尔滨市各城市发展因素与污染物浓度关联度不显著. 相似文献
93.
介绍了油田汽车下长坡、在发动机排气制动、在泥泞和湿滑的路面上行驶、在冰雪道路上行驶、在上坡道上起步、平时停车时等6个方面应该注意的安全技术问题,以及平时行车应该注意的安全、健康和环境问题。 相似文献
94.
武汉城市圈土地利用变化系统仿真模拟与驱动力分析 总被引:2,自引:0,他引:2
土地利用变化是全球环境变化与可持续研究的重要内容,驱动力研究是土地利用变化研究中的核心问题。现有土地利用变化驱动力研究多针对单一的城市区域展开,无法解释城市群地区,城市一体化战略指导下城市交互作用对土地利用变化的影响。运用系统动力学(SD)方法,综合考虑经济、人口、城市化、政策等主要人文因素,并将城市交互作用因素引入SD,以武汉城市圈为例,构建土地利用变化系统SD模型,运用1997~2006年的历史数据进行检验,并对武汉城市圈2010~2020年不同情景下的土地利用变化进行模拟。结果表明,建立的SD模型是有效的,两种情景下土地利用变化表现出差异性,说明城市交互作用是除经济、人口城市化等社会经济因素外,土地利用变化的又一重要影响因素。 相似文献
95.
为明确螺旋匝道(螺旋桥)驾驶操纵行为及车辆状态特征,选取2条桥头立交螺旋匝道和2座螺旋桥,开展小客车实车路试,通过连续采集行驶速度、加速度、踏板力等驾驶数据,分析螺旋匝道(桥)及前后衔接段的纵向驾驶行为特性.结果表明:行驶速度在螺旋匝道范围内基本恒定,并明显高于设计速度,螺旋匝道段的速度分布比主线段更集中,螺旋匝道对驾... 相似文献
96.
Associations between driver training, determinants of risky driving behaviour and crash involvement 总被引:1,自引:0,他引:1
Torbjrn Tronsmoen 《Safety Science》2010,48(1):35-45
The core aim of the study is to examine associations between formal and informal practical driver training as well as driving experience on the one hand and young drivers’ safety attitudes, self-assessment of driving ability and self-reported driver behaviour on the other hand. An additional aim is to examine the associations between attitudes, self-assessment and behaviour on the one hand and crash involvement on the other hand. The results are based on a self-completion questionnaire survey conducted among a representative sample of Norwegian drivers aged 18–20 years (n = 1419). The results showed that there were small yet significant associations between driver training, on the one hand and traffic safety attitudes and risky driving behaviour on the other hand. The amount of formal driver training was negatively associated with the respondents’ evaluation of their driving skills; although the amount of lay instruction was positively associated with such self-evaluation. The results also showed that attitudes as well as self-assessment of driving ability were significantly associated with self-reported risk behaviour. This was especially true for attitudes related to rule violations. There was a strong association between crash involvement and exposure (measured as months holding a licence). Young novice drivers’ crash involvement seems stronger associated with driving skills (manifested as self-assessment of driving ability) than safety attitudes and self-reported driver behaviour. The consequences of the results for driver training and accident prevention are discussed. 相似文献
97.
Mann RE Stoduto G Butters J Ialomiteanu A Boase P Asbridge M Chipman M Wickens CM 《Journal of Safety Research》2010,41(5):445-449
Introduction
The purpose of the current study was to examine differences in factors associated with self-reported collision involvement of three age groups of drivers based on a large representative sample of Ontario adults. Method: This study was based on data from the CAMH Monitor, an ongoing cross-sectional telephone survey of Ontario adults 18 years and older from 2002 to 2005. Three age groups were examined: 18-34 (n = 1,294), 35-54 (n = 2,428), and 55+ (n = 1,576). For each age group sample, a logistic regression analysis was conducted of self-reported collision involvement in the last 12 months by risk factor measures of driving exposure (kilometers driven in a typical week, driving is stressful, and driving on busy roads), consuming five or more drinks of alcohol on one occasion (past 12 months), cannabis use (lifetime, and past 12 months), and driving after drinking among drinkers (past 12 months), controlling for demographics (gender, region, income, and marital status). Results: The study identified differences in factors associated with self-reported collision involvement of the three age groups of adult drivers. The logistic regression model for the youngest group revealed that drivers who reported that driving was stressful at least some of the time, drank five or more drinks on an occasion, and drove after drinking had an increased risk of collision involvement. For the middle age group, those who reported using cannabis in the last 12 months had significantly increased odds of reporting collision involvement. None of the risk factor measures showed significant associations with collision risk for older drivers (aged 55+). Impact: The results suggest potential areas for intervention and new directions for future research. 相似文献98.
Anne T. McCartt Author Vitae Laurie A. Hellinga Author VitaeAuthor Vitae 《Journal of Safety Research》2010,41(2):173-181
Objective
To examine trends in alcohol consumption and alcohol-related crashes among people younger than 21 in the United States and to review evidence on the effects of minimum legal drinking age (MLDA) laws.Methods
Trends in alcohol-related crashes and alcohol consumption among young people were examined, and studies on the effects of lowering and raising the drinking age were reviewed.Results
MLDA laws underwent many changes during the 20th century in the United States. Since July 1988, the MLDA has been 21 in all 50 states and the District of Columbia. Surveys tracking alcohol consumption among high school students and young adults found that drinking declined since the late 1970 s, and most of the decline occurred by the early 1990 s. These were the years when states were establishing, or reinstating, a MLDA-21. Among fatally injured drivers ages 16-20, the percentage with positive BACs declined from 61% in 1982 to 31% in 1995, a bigger decline than for older age groups; declines occurred among the ages directly affected by raising MLDAs (ages 18-20) and among young teenagers not directly affected (ages 16-17). Almost all studies designed specifically to gauge the effects of drinking age changes show MLDAs of 21 reduce drinking, problematic drinking, drinking and driving, and alcohol-related crashes among young people. Yet many underage people still drink, many drink and drive, and alcohol remains an important risk factor in serious crashes of young drivers, especially as they progress through the teenage years. Stepped-up enforcement of MLDA and drinking and driving laws can reduce underage drinking. Recent efforts to lower MLDAs to 18 and issue licenses to drink upon completion of alcohol education have gained local and national media attention. There is no evidence that alcohol education can even partially replace the effect of MLDA-21.Conclusions
The cause and effect relationship between MLDAs of 21 and reductions in highway crashes is clear. Initiatives to lower the drinking age to 18 ignore the demonstrated public health benefits of MLDAs of 21.Impact on Industry
Lowering the drinking age to 18 will increase highway crash deaths among young people. 相似文献99.
驾驶员注意涣散检测技术研究 总被引:1,自引:1,他引:0
通过对注意涣散时驾驶员头部运动及面部表情变化特征的分析,系统实时监测驾驶员眼睛、嘴巴位置和运动状态信息,构建驾驶员注意涣散特征表征参量,实现对驾驶员注意涣散状态信息的检测与提取。驾驶员注意涣散表征量具有复杂的非线性特征,利用BP神经网络非线性识别的优势对驾驶员注意特征进行模式分类,实现驾驶员不同注意涣散状态下的特征捕捉。同时采用Dempster-Shafer证据推理技术,对驾驶注意涣散多源表征信息进行决策融合,实现对驾驶员注意涣散状态的判断。结果表明,BP神经网络与D-S规则多源信息决策融合技术的运用提高了驾驶员注意涣散特征检测的准确性和可靠性。 相似文献
100.
在通过可达性方法确定长江中游城市群县域范围的基础上,运用熵值法从人口、经济及社会3个子系统对长江中游城市群县域2001、2006及2011年3个时期城镇化发展水平进行综合测度,运用空间自相关对综合城镇化水平的空间演变进行分析并分类,利用回归分析对各类型县域进行驱动因子分析。结果表明:(1)长江中游城市群县域综合城镇化水平持续提升,但各地区间的发展速度差异明显;在子系统演化过程中,以经济城镇化的快速演进为主要特征,其次为社会城镇化,最后为人口城镇化过程。(2)综合城镇化水平及其变化率与城市等级规模、交通及产业结构转型密切相关;各子系统在空间格局演变进程中有着不同的特点,但子系统变化率间具有明显的正相关性。(3)长江中游城市群县域城镇化依据关联性可以划分为"耦合聚集"型、"中心洼地"型、"拮抗聚集"型及"核心边缘"型,各类型县域空间格局演变明显。(4)內源力在"耦合聚集"型县域及"拮抗聚集"县域城镇化进程中具有促进作用,投资力对"中心洼地"型县域影响作用明显,而"核心边缘"型县域主要驱动因子为行政力和內源力;根据各类型县域主要驱动因子提出促进城镇化发展的相应措施,以做到因地制宜地指导各地区城镇化健康发展。 相似文献