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211.
Fuzzy assessment of land suitability for scientific research reserves   总被引:1,自引:0,他引:1  
Evaluating the characteristics of a set of sites as potential scientific research reserves is an example of land suitability assessment. Suitability in this case is based upon multiple criteria, many of which can be linguistically imprecise and often incompatible. Fuzzy logic is a useful method for characterizing imprecise suitability criteria and for combining criteria into an overall suitability rating. The Ecosystem Management Decision Support software combined a fuzzy logic knowledge base we developed to represent the assessment problem with a GIS database providing site-specific data for the assessment. Assessment of sites as a potential natural reserve for the new University of California campus at Merced demonstrates the benefits of fuzzy suitability assessment. The study was conducted in three stages of successively smaller assessment regions with increasingly fine spatial resolution and specificity of criteria. Several sites were identified that best satisfy the suitability criteria for a reserve to represent vernal pool habitat.  相似文献   
212.
ABSTRACT: An analysis of hydrograph recessions and rainfall data was performed to estimate the recession constants for two watersheds in the Luquillo mountains of Puerto Rico. To account for seasonal rainfall patterns, the data were grouped into dry and wet seasons. Sets of three Master Recession Curves (MRC) per season for each watershed were developed: one using the Matching Strip Method (MS) and two using variations of the Correlation Method (CM). These variations were the envelope line (CME) and the least squares regression (CMR). Other regression based analytical expressions that consider the streamflow recession as an autore‐gressive or an integrated moving average process were also applied. The regression based methods performed consistently better than the graphical ones and they proved to be faster, easier, and less subjective. The recession constants from these methods were then used to estimate the time it would take the streamflow to reach the critical Q99 flow duration. Based on this study, once the streamflow reaches Q90, water managers have 6 to 12 days warning before streamflow reaches critical levels.  相似文献   
213.
基于GIS工业危险源和隐患控制及应急调控技术的应用研究   总被引:6,自引:6,他引:6  
笔者把面向对象方法及地理信息系统 (GIS)的技术应用于工业危险源与隐患控制及其应急调控技术中。介绍了面向对象的工业危险源、隐患控制及应急调控地理信息系统的功能、特点、开发环境以及设计与系统实现 ,旨在研究和探索更加完善和科学的现代化安全管理模式  相似文献   
214.
本文分析了宁南山区农业生产条件和存在的问题,认为宁南山区农业资源十分丰富,只要合理开发利用,宁南山区必将成为我区油料、大豆、畜产品的生产基地,并相应地提出了加速开发宁南山区农业资源的措施。  相似文献   
215.
ABSTRACT: In Illinois, a procedure has been developed to derive unit hydrographs for generating 100-year and probable maximum flood hydrographs, on the basis of 11 parameters that define the hydrograph shape very well. Regional regressions of these parameters with basin factors show very high correlation. Thus satisfactory values of parameters can be determined for ungaged areas or those with a few years' record. The nonlinearity in unit hydrographs derived from usual floods is largely attributed to mixing within-channel and overbank-flow flood events. To minimize the effects of nonlinearity and to derive unit hydrographa suitable for calculating spillway design floods, use of the proposed method of developing such hydrographs is recommended.  相似文献   
216.
ABSTRACT: Streams are dynamic systems, so steady state does not exist for any appreciable period of time. Streams in dynamic equilibrium respond quickly to change, regaining a new equilibrium. From the response system it follows that there is a causative reason why a stream meanders or degrades or aggrades its bed. These actions represent adjustment processes. If humans interfere with them, other adjustment processes will be initiated. In contrast, if humans work with the ongoing processes, success will be attainable with less efforts and at a lower cost. Local base level change represents one of the most influential channel changes, especially the lowering of this level. Loss of base level may cause degradation throughout a stream network, because the main stem is the base level for all its tributaries. Often, degradation causes bank instability and lowering of streamside water tables that, in turn, endanger the riparian ecosystem. Judging from check dam systems, a rise of the local base level does not raise the bed throughout a stream or network; instead, aggradation stops at a given distance. Preventing local base level changes of a stream network, therefore, is a cost-effective measure. Examples are presented of treatments causing new critical situations and measures to correct them.  相似文献   
217.
本文分析评价了温州市农业资源,农业开发条件与潜力,提出了农业区域开发的指导思想,总体目标与主要任务,确定了农业商品生产基地,划分了农业开发区,阐述了农业区域开发的对策与措施。  相似文献   
218.
高等院校环保专业实训基地是培训学生职业技能和综合素质的平台,实训基地的构建模式可采取在校内建立与环保产业运作一一对应的模拟仿真或真实岗位实训基地,也可在校外建立校企联合实训基地,建设实训基地要有切实可行的管理计划与措施,要结合环保产业运营机制积极探索产学研合作的实践教学新模式,实训基地的建设同时要创造良好的经济效益。  相似文献   
219.
创建安全社区之伤害调查与风险辨识方法探讨   总被引:3,自引:0,他引:3  
从事故与伤害预防和干预的角度,提出社区事故和伤害的种类,风险识别的范围和内容。依据较为成熟的伤害流行病学和系统安全工程理论,结合中国社区的构成特点,指出以社区事故预防为目的,不仅要提高社区居民的安全意识、行为和能力,更要为居民提供安全的工作场所和居住环境,加强危险因素的识别和控制。强调对设备设施、环境进行风险识别时,应采用安全检查表法和经验法;社区人群伤害基础调查可采用普查、随机抽样、医疗机构诊疗记录、特定人群调查、特定场所调查和伤害类型调查等6种方法;同时介绍了上述方法的基本原理、内容、实施步骤和适用范围,可供安全社区创建时参考。  相似文献   
220.
地震灾害是自然灾害之首,地震造成的建筑物破坏倒塌是人员伤亡财产损失的主因,特别是在小城镇、农村,大量的未纳入抗震管理也无抗震措施的多层建筑,面临诸多地震安全隐患,多维隔震体系是多层建筑地震安全的有效保障,从建筑物基础下部的垫层隔震到基础上部的滑移隔震层,再会同基础周边的隔震带,三种隔震方法在三个方面综合互补共同作用,使建筑基础底部到建筑周边都能阻隔消减地震波对建筑结构产生的影响,以达到隔震的目的。  相似文献   
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