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331.
PROBLEM: Road accident outcomes are traditionally analyzed at state or road network level due to a lack of aggregated data and suitable analytical methods. The aim of this paper is to demonstrate usefulness of a simple spatiotemporal modeling of road accident outcomes at small-scale geographical level. METHOD: Small-area spatiotemporal Bayesian models commonly used in epidemiological studies reveal the existence of spatial correlation in accident data and provide a mechanism to quantify its effect. The models were run for Belgium data for the period 2000-2005. Two different scale levels and two different exposure variables were considered under Bayesian hierarchical models of annual accident and fatal injury counts. The use of the conditional autoregressive (CAR) formulation of area specific relative risk and trend terms leads to more distinctive patterns of risk and its evolution. The Pearson correlation tests for relative risk rates and temporal trends allows researchers to determine the development of risk disparities in time. RESULTS: Analysis of spatial effects allowed the identification of clusters with similar risk outcomes pointing toward spatial structure in road accident outcomes and their background mechanisms. From the analysis of temporal trends, different developments in road accident and fatality rates in the three federated regions of Belgium came into light. Increasing spatial disparities in terms of fatal injury risk and decreasing spatial disparities in terms of accident risk with time were further identified. IMPACT ON INDUSTRY: The application of a space-time model to accident and fatal injury counts at a small-scale level in Belgium allowed identification of several areas with outstandingly high accident (injury) records. This could allow more efficient redistribution of resources and more efficient road safety management in Belgium.  相似文献   
332.
Stormwater ponds have become common features of modern development and often represent significant amounts of open space in urbanized areas. Although stormwater ponds may provide habitat for wildlife, factors responsible for producing variation in wildlife use of ponds have received limited attention. To investigate the role of variation in species tolerances of pollutants in structuring pond-breeding amphibian assemblages, we exposed species tolerant (Bufo americanus) and not tolerant (Rana sylvatica) of urbanization to pond sediments in laboratory microcosms. Pond microcosms had elevated sediment metal levels and chloride water concentrations. Among R. sylvatica embryos, exposure to pond sediments resulted in 100% mortality. In contrast, B. americanus embryos and larvae experienced only sublethal effects (i.e., reduced size at metamorphosis) due to pond sediment exposure. Our results suggest variation in pollutant tolerance among early developmental stages of amphibians may act in concert with terrestrial habitat availability to structure amphibian assemblages associated with stormwater ponds.  相似文献   
333.

Introduction

China has the world's largest population, and is the second largest automobile market. China's economy is booming, resulting in a rapid increase in both the road infrastructure and access to private vehicles. Along with economic growth, the ownership of motorized vehicles has almost quadrupled in the past 10 years, from 42.2 million in 1997 to 159.7 million in 2007. However, at the same time, China also has a very high number of road fatalities compared to other countries, with about 100,000 reported fatalities each year.

Method

This study analyzes the Chinese road-fatality situation to identify areas in which the total harm caused by crashes can be substantially and readily reduced. It provides a comprehensive analysis of the current road-fatality situation in China using conventional indices and the likely future trends.

Results

Four areas were identified in which countermeasures have the most potential to substantially reduce fatalities in China: pedestrians and other non-motorists, nighttime driving, vehicle passengers, and motorcycles.

Conclusion

While China faces unprecedented road safety issues, this report identifies major areas in which there are opportunities to greatly reduce total harm.  相似文献   
334.
为有效引导和管控突发公共卫生事件网络舆情,考虑社会相关性和网络群体间情绪状态转移的不确定性,基于社会燃烧理论研究突发公共卫生事件网络情绪传播机制.首先基于社会燃烧理论分析网络用户群体的社会影响因素,建立未燃-阴燃-燃烧-抑燃-稳定(UDBFS)网络情绪传播模型和考虑干预措施的网络情绪传播模型;然后以新冠肺炎(COVID...  相似文献   
335.
Elena Lucchi 《Disasters》2010,34(4):973-995
Cities are fast becoming new territories of violence. 1 The humanitarian consequences of many criminally violent urban settings are comparable to those of more traditional wars, yet despite the intensity of the needs, humanitarian aid to such settings is limited. The way in which humanitarian needs are typically defined, fails to address the problems of these contexts, the suffering they produce and the populations affected. Distinctions between formal armed conflicts, regulated by international humanitarian law, and other violent settings, as well as those between emergency and developmental assistance, can lead to the neglect of populations in distress. It can take a lot of time and effort to access vulnerable communities and implement programmes in urban settings, but experience shows that it is possible to provide humanitarian assistance with a significant focus on the direct and indirect health consequences of violence outside a traditional conflict setting. This paper considers the situation of Port‐au‐Prince (Haiti), Rio de Janeiro (Brazil) and Guatemala City (Guatemala).  相似文献   
336.
中国道路建设生态补偿机制建立的理论思考   总被引:6,自引:1,他引:5  
生态补偿是目前研究的一个热门课题,建立生态补偿机制是一项复杂的系统工程。本文以道路生态补偿为例,概括了中国道路建设的现状和建立生态补偿机制的必要性,重点从理论上分析了中国建立道路建设生态补偿机制的思路和实现途径。  相似文献   
337.
确定中国对外直接投资(OFDI)对CO2排放的影响路径,对"一带一路"沿线国家如何有效利用中国OFDI以实现可持续发展具有重要作用。该研究基于2003—2018年45个沿线国家的面板数据,应用具有阈值和动态特征的面板平滑转换回归(PSTR)模型,评估中国OFDI对CO2排放的直接效应和间接效应、线性效应和非线性效应。研究发现:(1)中国OFDI对沿线国家CO2排放的直接影响显著为负。(2)中国OFDI的规模效应增加了沿线国家CO2排放,其结构效应和技术效应进一步抑制了沿线国家CO2排放,且技术效应在间接效应中占有主导地位。(3)异质性分析表明,中国OFDI的碳减排效应更多体现在低收入国家。针对以上研究发现,文章认为沿线国家应持续引进中国OFDI,并通过提高能效和推广应用清洁能源打破经济发展的"不可持续性";中国政府应继续鼓励并引导具有竞争力的企业"走出去",充分发挥中国投资对东道国环境的改善作用,放大中国投资对低收入国家的技术溢出效应;中国应根据沿线国家经济发展水平对东道国实施差异化投资策略,实现中国投资环境效益最优化。  相似文献   
338.
基于GIS的道路交通安全管理系统的研究   总被引:4,自引:6,他引:4  
针对道路交通安全的现状 ,笔者分析了利用地理信息系统 (GIS)建立道路安全管理系统的必要性及优点 ,探讨了基于GIS的道路安全管理系统的功能、设计思路及其开发的技术路线。利用GIS进行交通安全管理可以增强交通事故分析的直观性、可操作性 ,进行区域安全评价、事故多发点因素分析 ,有利于挖掘交通事故的深层原因 ,从而指导安全管理工作。基于GIS的道路交通安全管理的研究 ,是GIS在领域应用和迅速提高道路交通安全管理现代化水平的一个创新性探索。  相似文献   
339.
道路交通安全管理规划体系初探   总被引:2,自引:7,他引:2  
《道路交通安全法》明确规定 :“要求县级以上地方各级人民政府应当适应道路交通发展的需要 ,依据道路交通安全法律、法规和国家有关政策 ,制定道路交通安全管理规划 ,并组织实施。”依据该条文的要求 ,笔者探讨了道路交通安全管理规划的作用 ,论述了道路交通安全管理规划体系的总体设计 ,提出了包括道路交通安全调查、交通安全管理现状评价和问题分析、交通安全趋势预测、交通安全管理目标确定以及具体专项规划等内容的道路交通安全管理规划体系。  相似文献   
340.
危险化学品道路运输系统危险性分析   总被引:21,自引:10,他引:21  
针对危险化学品道路运输中的安全问题 ,建立了危化品道路运输系统模式和系统危险性评价程序。应用所开发的ACES软件系统对汽车燃料汽油的替代品LPG的道路运输进行了最大事故后果分析评价 ,并提出了建议和对策。研究结果不仅能够为危化品道路运输系统危险性的控制和预防提供科学指导 ,还能为减少系统事故损失及事故时的应急疏散等提供参考数据 ,具有潜在的经济效益和社会效益。  相似文献   
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