首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   233篇
  免费   15篇
  国内免费   6篇
安全科学   106篇
废物处理   3篇
环保管理   38篇
综合类   54篇
基础理论   5篇
污染及防治   23篇
评价与监测   13篇
社会与环境   9篇
灾害及防治   3篇
  2023年   3篇
  2022年   5篇
  2021年   20篇
  2020年   21篇
  2019年   14篇
  2018年   6篇
  2017年   8篇
  2016年   10篇
  2015年   3篇
  2014年   5篇
  2013年   7篇
  2012年   13篇
  2011年   22篇
  2010年   9篇
  2009年   15篇
  2008年   16篇
  2007年   4篇
  2006年   8篇
  2005年   16篇
  2004年   14篇
  2003年   9篇
  2002年   3篇
  2001年   5篇
  2000年   2篇
  1999年   3篇
  1998年   2篇
  1997年   3篇
  1996年   2篇
  1995年   1篇
  1994年   4篇
  1985年   1篇
排序方式: 共有254条查询结果,搜索用时 15 毫秒
241.
论"绿色GDP"核算体系及其面临的问题   总被引:6,自引:0,他引:6  
阐述了"绿色GDP"理论的形成与发展,结合中国国情,探讨了"绿色GDP"核算体系,进而分析了当前中国实现"绿色GDP"核算所面临的主要问题,提出了实现"绿色GDP"核算的主要对策和措施.从而让人们放弃传统的经济发展模式,采用循环经济发展模式,走新型工业化道路.  相似文献   
242.
上海城市交通建设中的可持续发展战略   总被引:4,自引:0,他引:4  
城市交通设施建设和交通管理是保证城市可持续发展不可残缺的必要条件之一,故用可持续发展的概念来重新审视交通建设的历史和现状是十分必要的。文章提出了弱持续,中持续和强持续的概念,以此从宏观和微观,供给和需求等方面对上海的交通设施管理状况作了粗浅的分析。  相似文献   
243.
Does air quality influence road safety? We estimate the effect of increased air pollution on the number of road traffic accidents in the United Kingdom between 2009 and 2014. To address concerns of spurious correlation we exploit atmospheric temperature inversions as a source of plausibly exogenous variation in daily air pollution levels. We find an increase of 0.3–0.6% in the number of vehicles involved in accidents per day for each additional 1 μg/m3 of PM2.5. The finding suggests that less safe roads may present a large and previously overlooked cost of air pollution. The results are robust to a number of specifications and across various sub-samples.  相似文献   
244.
Over the past two decades the concept of driver distraction has been the focus of intense research attention. One aspect of distraction for which there has been limited systematic research, however, is its role in driver error causation. This article presents a review of the distraction literature with a view to elucidating what is currently known about the types of driving errors that distraction contributes to and the mechanisms by which distraction induces these errors. The review revealed a number of fundamental gaps in our knowledge, including the number and nature of errors made by drivers when distracted; the mechanisms by which distraction causes errors; whether and how distraction disrupts drivers’ ability to recover from errors; and how system-wide factors moderate the relationship between distraction and error. In closing, we attempt to identify the most appropriate theoretical and methodological approach to drive the integrated study of distraction and error forward. We conclude that it is only through the adoption of a systems approach that integrated countermeasures can be proposed and implemented to mitigate driver errors caused by distraction.  相似文献   
245.
This study compared the actual and perceived social norms regarding road crossing behaviors, and aimed at uncovering a misperception of group norms. The basic notion underlying the study was that if children perceived the behaviors and attitudes of their friends regarding road crossing as more negative than they actually are, this might lead the children to adopt riskier behavior when crossing the road. The participants were comprised of 123 elementary school children (ages from 6 to 13; 78 boys - 65% and 42 girls - 35%) from Beitar-Ilit, a religious city in Israel. A questionnaire especially constructed for the study was administered to the participants. A t-test yielded a significant difference between the child’s own attitudes score and the perceived peers’ attitudes score. On average, children perceive their friends’ attitudes with regard to road crossing behaviors as being more negative compared to their own attitudes. A second t-test yielded a significant difference between the child’s own behavior score and the perceived peers’ behavior score. Children perceived the road crossing behavior of their friends as riskier relative to their own crossing behavior. A regression test revealed that the variables, perceived peers’ attitudes and perceived peers’ behaviors, contributed significantly to the explained variance: the more risky the perceived peers’ attitudes and behaviors with regard to road crossing, the more risky the child’s own behavior when crossing the road. It is hoped that an interventional educational program based on positive norms in the social group will encourage children to exhibit safe behavior in the roads.  相似文献   
246.
Almost four years after the entry into force of Regulation ECE 123 on Adaptive Front-lighting Systems (AFS) for motor vehicles, and once the first cars bearing them start to circulate, a comparison between the original idea of AFS and their potential impact in safety and accident prevention is possible. In this work, we present the basic concepts of this new way to light roads and analyse some unforeseen consequences that might arise within the ECE regulatory framework once the presence of AFS becomes massive. This paper also pretends to be an useful guide for some countries like China, still considering the best way to definitively regulate these complex systems whose impact on road safety is expected to be huge.  相似文献   
247.
基于面向对象的北京市区城市内部用地信息提取   总被引:1,自引:0,他引:1  
选取北京市四环以内为研究区域,以资源三号卫星遥感影像为数据源,针对类型多样、特征易混淆的城市内部用地以及高分辨率遥感影像海量信息、人工提取费时费力等特点,论文基于面向对象分类方法,探讨城市内部用地自动提取方法,并对分类结果进行精度评估.结果表明:利用不同地物的光谱、形状、纹理和空间关系等特征,通过多尺度分割和隶属度函数法,构建合理的分类层次,不仅精确提取出研究区内水体、绿地、建设用地和待开发用地,更独具创新地区分了城市建设用地内部各种地物类型,包括工业生产用地、低密度和高密度生活用地以及交通用地.该方法有效地利用了资源3 号卫星影像的光谱、纹理及空间信息特征,总体精度可达到87.00%,Kappa系数达到0.853 9,取得较好的分类效果.  相似文献   
248.
The CAL3QHC model was used to predict carbon monoxide (CO) concentrations from motor vehicles at an existing urban intersection (Star Cinema in Muscat area, Oman). The CO concentrations predicted from the model were compared with those measured in the field. Predicted average CO concentrations were found to compare favorably with measured values obtained at all eight receptors considered within the modeled intersection. In general, the comparison indicates good agreement with some underprediction for CO. For receptor 6, the model overpredicts the average CO concentration. This overprediction is associated with the presence of trees and green area in the location of receptor 6. In general, the measurements and the model results indicated that the highest CO concentrations were found to occur close to the intersection and, hence, a decrease in the concentration levels was seen as the distance from the road increased. The results indicated that the levels of CO were well below the ambient air quality standard and that probably no health risk was present in areas adjacent to the star cinema intersection. However, the predicted worst-case 1-h CO concentrations assuming inversion atmospheric stability conditions (class F) and wind speed of 1 m/s indicated that the levels of CO were close to or higher than the Omans National Ambient Air Quality Standards (NAAQS) value of 35 ppm at all receptors considered. The results of this study are useful in transport development and traffic management planning.Published online.  相似文献   
249.
中美两国汽车驾驶安全影响因素研究   总被引:8,自引:4,他引:4  
影响汽车驾驶安全的各国道路交通系统以及驾驶员的驾驶行为等存在着差异性 ,许多差异可以通过统计数据的分析 ,或者其他定量研究方法获取 ,但仍然有许多影响驾驶安全的因素难以发现。笔者通过焦点团体座谈会的方法 ,从驾驶者的角度 ,搜集并分析了中美两国驾驶安全的主要影响因素 ,以及具有美国驾驶经历会对我国驾驶员有何影响。通过中美两国定性数据的对比分析 ,得出了主要影响因素 ,与此同时 ,通过问卷调查定量地分析了这些因素的严重程度。  相似文献   
250.
The purpose of this study was to assess the effects of a two-day post-license driver-training program on brake performance in cars with antilock braking systems (ABS). A trainee group (n = 26) and a control group (n = 13) participated in the experiment. The trainee group were enrolled in a two-day training course that included instruction in a braking technique that may be used in cars with and without ABS. All participants performed emergency brake tests from 80 and 100 km h−1 in an instrumented car before and after the training period. Results indicated the post-training group used a smoother braking profile, were less reliant on ABS activation, had enhanced postural stability, but took about one car length longer to stop from 100 km h−1 compared with the control group. Implications of these results for braking in cars with and without ABS, and for driver education programs in general are discussed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号