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51.
江苏海岸带土地利用变化及驱动力分析   总被引:7,自引:0,他引:7  
通过对江苏海岸带近13a的土地利用变化和社会经济分析,得出:连云港海岸带以耕地、其他建设用地和农村居民点为主,占81%,海岸带开发程度高;斑块个数增加,景观破碎化增大。盐城以耕地、草地和其他建设用地为主,占77.45%,开发程度中等;耕地、水库坑塘等人工景观面积增大,适宜生物多样性保护的生境面积减少。南通海岸带以耕地和滩涂为主,占88.93%,但两者的面积都在下降;人工景观面积增加。人口增长的压力、政府政策的导向与社会经济的驱动是江苏沿海三市海岸带景观格局变化的主要驱动力。连云港海岸带人口密度增加了13.8%,第二产业产值增加了7.7倍,人类活动的干扰使海岸带破碎明显;盐城海岸带人均GDP增加了4倍,经济利益的驱使,使盐城丧失大面积的草地,海岸湿地遭到破坏;南通海岸带人口密度减小了2.0%,人均GDP增加了5.3倍,第三产业的发展对海岸带干扰较小,海岸带景观破碎度较低。  相似文献   
52.
A typical driving restriction prohibits drivers from using their vehicles on given weekdays, based on the last digits of their vehicles’ license plates. A number of cities in developing countries have used license plate-based driving restrictions as a policy for reducing urban air pollution and traffic congestion. This paper develops a theoretical model of the effects of license plate-based driving restrictions on air quality that combines an economic model with information about the sources and atmospheric chemistry of different air pollutants. We then draw upon suggestive empirical evidence from license plate-based driving restrictions implemented in Bogotá, Colombia. Consistent with our theory model, we find suggestive empirical evidence that under certain circumstances, due to substitution, the purchase of a second car, the use of alternative modes of transportation, and/or atmospheric chemistry, it is possible for license plate-based driving restrictions to increase air pollution. Also consistent with our theory, we find that license plate-based driving restrictions may have different effects on different air pollutants, reflecting heterogeneity in the sources and atmospheric chemistry of the pollutants. In particular, owing to atmospheric chemistry, it is possible for a license plate-based driving restriction to cause a significant decrease in NO and a significant increase in NO2, NOx, and O3.  相似文献   
53.
在计算石油化工储罐火灾扑救所需的消防力量时,引入储罐特性重要度的概念。通过分析影响石油化工储罐特性重要度的各个因素以及因素间的相互联系,构建了较合理的储罐特性重要度评价指标体系,并利用层次分析和多级模糊评价相结合的方法,确定储罐特性重要度系数。应用研究表明,在计算石油化工储罐火灾所需消防资源时,应考虑到储罐特性重要度对资源需求的影响。储罐特性重要度越大,对消防资源的需求就越大,在储罐发生火灾时调集的消防力量就越多。储罐特性重要度的确定为消防指挥员在扑救石油化工储罐火灾时调集合理的消防力量,提供了科学的决策依据。  相似文献   
54.
Abstract

China is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment, particularly in the costal areas. This study takes Jinan as a case presenting a time-series analysis of urban land expansion from 313 to 2003. The results show that the urban expansion of Jinan city mainly took place in the last 100 years, especially after the economic reform in 1978. Social development and economic growth, urban population growth and migration policies were factors driving the urban land expansion. Urban sprawl resulted in a disappearance of wetlands and a great loss of agricultural land, and over-pumping of ground water that led to disappearance of the city's feature, namely “the city of springs”.  相似文献   
55.
采用上海市车辆数据和机动车年检站实地调查方式获取车辆技术及分布,用GPS设备采集机动车行驶工况,通过交通流量录像的现场计数的方法获得道路车流分布。调查结果显示,在用汽车排放水平85%以上都达到或超过国Ⅱ标准;在低速、怠速工况区间内,社会车辆的比功率比例最低;道路轻型客车(含出租车)日平均车流量占总车流量的80%以上。机动车活动水平的详细调查将有助于上海实际道路机动车排放清单的精确计算,并获取主要的排放源及其影响因素。  相似文献   
56.
湛江市农村居民点用地面积变化及驱动力分析   总被引:4,自引:0,他引:4  
利用湛江市1996—2005年农村居民点用地面积数据及相关社会经济数据,在分析农村居民点用地面积变化的基础上,采用主成分分析法对其进行了驱动力分析。结果表明,近十年来湛江市农村居民点用地总面积呈逐年上升的趋势,而农村居民点人均用地面积总体呈减少趋势。湛江市农村居民点用地面积增加主要集中在徐闻、吴川和市区。湛江市农村居民点用地面积变化主要受农村人口增长、农村经济发展、农业结构调整、农村交通发展和乡镇企业发展等因素的影响。  相似文献   
57.
Objective: Traffic injuries are becoming one of the most important challenges of public health systems. Because these injuries are mostly preventable, the aim of this study is to evaluate the four main high-risk behaviors while driving.

Methods: This cross-sectional study was conducted on a random sample from the population of Mashhad, Iran, in 2014. A checklist and a previously validated questionnaire for the transtheoretical stages of change model (TTM) were used for data collection. Statistical analyses were performed using SPSS 11.5 software with P <.05 statistically significant.

Results: Totally 431 individuals were included with a mean age of 30 ± 11.3 years. Forty-three percent (183) were male. The TTM model revealed that participants were mostly in pre-actional phases regarding not using a cell phone while driving (80%), fastening the driver's seat belt (66%), front seat belt (68%), and rear seat belt (85%) The penalty was a protective factor only for using cellphone (odd ratio [OR] = 0.82, 95% confidence interval [CI], 0.68–0.98). Lower education (OR = 0.12, 95% CI, 0.01–0.94) and male gender (OR = 0.35, 95% CI, 0.14–0.83) were indicative of lower rates of fastening the front and rear seat belts.

Conclusion: The stages of change model among study participants is a proper reflection of the effectiveness of the current policies. More serious actions regarding these high-risk behaviors should be considered in legislation.  相似文献   

58.
Objective: The objective of this article was 2-fold: firstly, we wanted to examine whether the original Driving Anger Scale (DAS) and the original Driving Anger Expression Inventory (DAX) apply to German professional taxi drivers because these scales have previously been given to professional and particularly to nonprofessional drivers in different countries. Secondly, we wanted to examine possible differences in driving anger experience and expression between professional German taxi drivers and nonprofessional German drivers.

Methods: We applied German versions of the DAS, the DAX, and the State–Trait Anger Expression Inventory (STAXI) to a sample of 138 professional German taxi drivers. We then compared their ratings to the ratings of a sample of 1,136 nonprofessional German drivers (Oehl and Brandenburg n.d. Oehl M, Brandenburg S. Driving anger in Germany: validation of the Driving Anger Scale (DAS). Saf Sci. n.d. submitted.  [Google Scholar]).

Results: Regarding our first objective, confirmatory factor analysis shows that the model fit of the DAS is better for nonprofessional drivers than for professional drivers. The DAX applies neither to professional nor to nonprofessional German drivers properly. Consequently, we suggest modified shorter versions of both scales for professional drivers. The STAXI applies to both professional and nonprofessional drivers. With respect to our second objective, we show that professional drivers experience significantly less driving anger than nonprofessional drivers, but they express more driving anger.

Conclusions: We conclude that the STAXI can be applied to professional German taxi drivers. In contrast, for the DAS and the DAX we found particular shorter versions for professional taxi drivers. Especially for the DAX, most statements were too strong for German drivers to agree to. They do not show behaviors related to driving anger expression as they are described in the DAX. These problems with the original American DAX items are in line with several other studies in different countries. Future investigations should examine whether (professional) drivers from further countries express their anger as proposed by the DAX. In addition, professional drivers experience less driving anger (DAS) and less general trait anger (STAXI) than nonprofessional drivers, but they report more driving anger expression (DAX) and more current general state anger (STAXI). Subsequent studies should therefore focus on different types of anger within the group of professional drivers.  相似文献   
59.
Introduction: The purposes of this study are to characterize Israeli undergraduate students' driving violations in the terms of problem behavior theory and to identify whether there is any relationship between driving violations and health risk behaviors, daring behaviors, excitement seeking, and health promotion behaviors.

Methods: This study is based on a structured self-reported anonymous questionnaire distributed to undergraduate students in an academic institution. The sample included 533 undergraduate students (374 females and 159 males). The mean age was 23.4 (SD = 1.4, range = 5).

Results: A higher prevalence of self-reported driving violations was found among males in comparison to females. All substance use measures were positively related to driving violations; for example, use of cigarettes (OR = 4.287, P <.001) and water pipes (odds ratio [OR] = 3.000, P <.001) as well as binge drinking (OR = 5.707, P <.001) and regular cannabis smoking (OR = 5.667, P <.001) raise the probability of committing rare driving violations. The strongest predictive factors for the frequent driving violations group were alcohol consumption–related variables: binge drinking (OR = 2.560, P <.01) and drunkenness (OR = 2.284, P <.05). Strong odd ratios were also found between the frequent driving violations group and selling or dealing drugs (12.143, P <.001), and stealing something valuable (13.680, P <.001). The strongest predicted variable for the rare driving violations group was physical confrontation due to verbal disagreement (3.439, P <.05) and the concept that selling or dealing drugs is socially acceptable (2.521, P <.05). The probability of executing rare driving violations was higher for subjects who reported intense physical workout regimens (OR = 1.638, P <.05).

Conclusions: Problem behavior theory succeeded in explaining health risk behavior and driving violations. This study shows that bachelors tend to be more involved in risk behaviors, such as substance use, excitement-seeking behaviors, and daring behaviors and are active physically and thus constitute a risk group for driving violations. As such, intervention resources should be directed toward this group.  相似文献   

60.
北京市丰台区土地利用变化及社会经济驱动力分析   总被引:2,自引:0,他引:2  
近十年来.北京城市化水平大幅度提升.建设用地不断向外扩展。城市边缘区土地利用变化异常明显。丰台区作为北京城市边缘区的重要组成部分。土地利用变化特征具有典型性,在分析丰台区12年间土地利用的类型变化、数量变化、程度变化和区域变化特征基础上。对形成这种土地利用变化的驱动力从社会经济方面进行了剖析,并在统计软件SPSS的支持下对土地利用变化驱动力指数进行了计算。结果表明.研究时段内土地利用变化幅度大。土地利用程度增加;耕地、园地和未利用地净减.而建设用地和林地净增.土地利用变化的社会驱动力主要是人口增长、经济发展和城市化水平提高.并且这些因素的驱动力指数是逐年增加的。政策的干预作用也不容忽视。  相似文献   
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