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   200篇
  免费   20篇
  国内免费   13篇
安全科学   34篇
废物处理   1篇
环保管理   31篇
综合类   74篇
基础理论   35篇
污染及防治   4篇
评价与监测   16篇
社会与环境   15篇
灾害及防治   23篇
  2023年   2篇
  2022年   3篇
  2021年   12篇
  2020年   8篇
  2019年   7篇
  2018年   5篇
  2017年   8篇
  2016年   7篇
  2015年   6篇
  2014年   5篇
  2013年   6篇
  2012年   10篇
  2011年   15篇
  2010年   10篇
  2009年   17篇
  2008年   9篇
  2007年   13篇
  2006年   3篇
  2005年   10篇
  2004年   7篇
  2003年   8篇
  2002年   5篇
  2001年   12篇
  2000年   3篇
  1999年   8篇
  1998年   4篇
  1997年   3篇
  1996年   4篇
  1995年   4篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1991年   3篇
  1990年   2篇
  1989年   2篇
  1988年   5篇
  1987年   1篇
  1983年   1篇
排序方式: 共有233条查询结果,搜索用时 15 毫秒
131.
陈小芳  戚洪飞  俞岗 《灾害学》2021,(1):117-121
地震灾害风险评估中有许多定性图件,目前常用的成图方法是根据研究区的离散点钻孔结果人工勾画,费时费力;或对离散点钻孔结果强制赋予0、1数值,然后进行插值成图,其从逻辑上不能真实反映场地的客观情况。基于支持向量机技术,该文提出了使用分类工具SVC,将不同结果的离散点钻孔在空间上进行合理分类的自动成图方法。相较于传统方法,该方法效率高,成本低。  相似文献   
132.
With the ever-increasing development of those chemical parks (concentrated areas), the inherent hazards may remain the major leading cause of serious casualties, causing dramatic increases in deaths and injuries. Despite this, proper path beforehand can effectively minimise the number of deaths or injured. In this study, in order to better address the aforesaid issue, the pre-evacuation path planning was adopted to do so. This method can serve to prepare emergency response in case of extreme events, such as fires, explosions, or dangerous leakages, because these accidents could happen in chemical parks (concentrated areas). To that end, a framework was therefore proposed. First, the general risk representation was conducted. After the main hazards as well as the vulnerability within the facilities was identified, the interaction between those two factors could be expressed with matrices. This was followed by the analysis of the domino effect, which tends to occur under such circumstances. Second, individuals' visibility and inclination at each location to choose the nearest exit gate or shelter zone were analyzed by space syntax analysis. Third, a weighted risk map mainly composed of risk, individual's visibility, and inclination of exits was therefore generated. And the lowest cumulative risk path was simulated and analyzed accordingly. Finally, the map modified with received risks suggests that each individual's safest route from their current locations can be possibly simulated with Dijkstra's algorithm, which corresponds to the lowest cumulative risk. For the purposes of illustration and validation, a real case was adopted. The results demonstrated that this framework could provide both technical and theoretical support for the pre-evacuation path planning in chemicals-concentrated areas like chemicals-concentrated areas.  相似文献   
133.
Mathematical models used to optimize the process plant layout (PPL) with risk reduction have four primary objectives, which are related to the minimization of land, pumping (pipe system), protection system devices, and risk costs. Moreover, these models are of two types: continuous plane models (CPM) and grid-based models (GBM); however, the nonconvexity of the CPM models makes difficult to achieve the global optimum, because it is formulated as Mixed-Integer Nonlinear Programming (MINLP). Thus, the risk map approach has been implemented with the grid-based models to solve problems of process plant layout focused on finding the best possible solution. However, these risk map formulations present important limitations, mainly related with the use of protection devices and the occupied area. Therefore, a new GBM-MILP formulation is proposed to optimize the selection of protection devices and minimize the occupied area. The risk is reduced through the investment on safety devices instead of considering the increase of separation distances. The proposed model was used to solve the layout problem of an ethylene oxide process, and the results was compared with a process layout reported in the literature. The results show that the model can provide the best possible solution; however, the time spent in the calculation is considerably greater than that reported for continuous plane models. Finally, the model can be used by decision-makers to evaluate different layout options for several explosion scenarios, during the early stages of the plant design.  相似文献   
134.
The state of the boundary layer at the release site during the two tracer experiments is described, based on measurements of atmospheric turbulence carried out by a sonic anemometer, profiles of horizontal and vertical wind by a SODAR as well as frequent radiosonde releases. The boundary layer height is derived from radiosoundings, modelled and discussed. The study is meant as background for discussions of the tracer behaviour near the release site, and possible influence of the local meteorology at the release site on the long-range dispersion. The difference in the initial meso-meteorological conditions between the two experiments is discussed and some of its consequences for the dispersion of the released tracer are clarified. It is concluded that the first experiment is well suited for validation of long-range transport and dispersion models, whereas the second experiment calls for further model development. It is concluded that the micrometeorological measurements are very important as background information for the understanding of plume behaviour on small as well as long scales.  相似文献   
135.
基于GIS组件的环境影响评价地图系统   总被引:2,自引:1,他引:1  
论述了利用GIS组件开发环境影响评价专题地图应用软件的优点 ,对系统的总体构思及功能进行了详细的说明 ,设计了环境地理信息系统处理模块的软件界面 ,实现了GIS的基本功能 ;对于处理完成的专题地图 ,建立图片数据库应用软件进行保存 ,并通过数据库实现地图库中图片的删除、浏览及打印等功能。本应用软件可广泛应用于环境影响评价领域 ,并对深层次的GIS软件开发具有一定的借鉴作用  相似文献   
136.
Floodplain delineation may inform protection of wetland systems under local, state, or federal laws. Nationally available Federal Emergency Management Agency Flood Insurance Rate Maps (FIRMs, “100‐year floodplain” maps) focus on urban areas and higher‐order river systems, limiting utility at large scales. Few other national‐scale floodplain data are available. We acquired FIRMs for a large watershed and compared FIRMs to floodplain and integrated wetland area mapping methods based on (1) geospatial distance, (2) geomorphic setting, and (3) soil characteristics. We used observed flooding events (OFEs) with recurrence intervals of 25‐50 to >100 years to assess floodplain estimate accuracy. FIRMs accurately reflected floodplain areas based on OFEs and covered 32% of river length, whereas soil‐based mapping was not as accurate as FIRMs but characterized floodplain areas over approximately 65% of stream length. Geomorphic approaches included more areas than indicated by OFE, whereas geospatial approaches tended to cover less area. Overall, soil‐based methods have the highest utility in determining floodplains and their integrated wetland areas at large scales due to the use of nationally available data and flexibility for regional application. These findings will improve floodplain and integrated wetland system extent assessment for better management at local, state, and national scales.  相似文献   
137.
Crisis mapping is a legitimate component of both crisis informatics and disaster risk management. It has become an effective tool for humanitarian workers, especially after the earthquake in Haiti in 2010. Ushahidi is among the many mapping platforms on offer in the growing field of crisis mapping, and involves the application of crowdsourcing to create online and interactive maps of areas in turmoil. This paper presents the Crisis Map of the Czech Republic, which is the first such instrument to be deployed nationwide in Central Europe. It describes the methodologies used in the preparatory work phase and details some practices identified during the creation and actual employment of the map. In addition, the paper assesses its structure and technological architecture, as well as its potential possible development in the future. Lastly, it evaluates the utilisation of the Crisis Map during the floods in the Czech Republic in 2013.  相似文献   
138.
全国大气润湿时间分布分析软件开发   总被引:1,自引:1,他引:0  
软件以小方块在地图上标注全国195个地区的实际位置,按ISO 9223标准对各地区的年润湿时间进行分级,并以不同的颜色对应不同的等级。使用软件可查询1991年至2000年全国195个地区大气润湿时间的分布状况;不同临界相对湿度的润湿时间;各年润湿时间的变化规律情况,包括10年润湿时间的平均值和标准差;年润湿时间在各温度段所占的比例。  相似文献   
139.
Surfer软件和AutoCAD在污染场地调查及风险评估中的应用   总被引:1,自引:0,他引:1  
在场地调查和风险评估报告中需要描述污染物分布和确定土壤修复区域和范围,目前对此无统一的技术要求,不同案例使用的技术方法不同。今提出将 Surfer软件和 AutoCAD结合使用生成等值线图件,以及据此确定污染土壤修复范围的方法,并基于某搬迁化工厂初步土壤调查及风险评估的案例介绍了操作步骤。旨在介绍2个专业软件联用的新功能的开发和使用技巧,为编制场地调查和风险评估报告提供一种便捷、易操作的工作方法。  相似文献   
140.
大气环境及腐蚀性   总被引:3,自引:3,他引:0  
根据近年来国内外对大气环境和腐蚀性的研究成果.描述了大气环境及腐蚀性的研究状况,介绍了国际标准化组织的分类分级标准和我国大气环境的腐蚀性的分类分级的探讨性研究以及大气腐蚀图的研究。  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