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231.
ABSTRACT: Information on raw water quality, treatment process removal efficiency, and distribution system monitoring is essential to the proper management and operation of a water utility system. Microcomputer hardware and software systems using commercially available data base management systems (DBMS) have emerged within the last few years as an effective means of managing, analyzing, and displaying water quality data. Understanding hardware, software, and training requirements is essential to the proper use of these systems. Three types of data base design are common: relational, hierarchical, and network. Only the relational type of data base architecture is widely implemented on microcomputer DBMS. In this paper two examples of the application of DBMS to water utility problems are presented. One example deals with collection and analysis of data concerning the water quality of the Mississippi River. The second example deals with the DBMS as a means of analyzing water quality data in the North Penn Water Authority (NPWA) distribution system.  相似文献   
232.
废旧电脑的处置现状与绿色电脑概念的普及   总被引:4,自引:0,他引:4  
慨述了发达国家在废电脑处理方面的现状,并对绿色电脑进行了分析与展望。  相似文献   
233.
甲型流感病毒H5N1的siRNA设计   总被引:1,自引:0,他引:1  
选用了甲型流感病毒10个毒株(全序列)和一个2004年越南毒株(部分序列),采用自己编写的计算机程序sRNAFinder,对每个毒株的6个RNA片段的6个编码序列进行了siRNA设计.结合系统发育重建方法,利用sR-NAFinder的共有序列分析功能,对得到的6101个siRNA分子进行了计算机筛选.结果表明,设计的siRNA的分子,针对np和pb1应该是最有效的,而针对ha和na的siRNA分子设计,需要疾病流行期毒株的最新测序数据;从ns1的数据不能获得很保守的、可作为预防治疗药物的siRNA分子.图1表4参16  相似文献   
234.
国内环境噪声监测仍沿袭着"仪器放点"、"数据整理"、"计算机录入"等旧的一套监测模式,自动化程度较低并且没有留存原始声级数据.文章介绍的用计算机实现环境噪声自动监测,比较好地解决了以上问题.文中对监测系统的功能要求、系统构成、系统软件以及系统的先进性作了简要的说明与阐述.  相似文献   
235.
针对复杂建筑物中人群安全疏散问题,在原有的元胞自动机行人流模型基础上,利用不同人员行进速度、不同方向行进速度的差异以及疏散连续性等特征优化该模型,使其在模拟逃生规律和疏散时间方面更加合理、可靠。通过多组人群行进速度测定试验,利用曲线拟合方法,获取不同属性人群向不同高度的台阶行进的速度,并制定台阶等级划分规则,优化人员速度计算方法,结合累积位移量,构建复杂建筑元胞自动机模型。利用Matlab软件建立原有疏散模型及复杂建筑元胞自动机模型,分别模拟某海豚表演馆疏散情况。结果表明,复杂建筑元胞自动机模型的模拟数据与实际演习数据相比,在疏散总时间方面存在5%~8%相对偏差,相比原有疏散模型,在模拟复杂建筑疏散问题中更具说服力。  相似文献   
236.
笔者提出了紧急疏散中狭义和广义信息传播原理,并在此基础上建立了一种基于信息传播系统的人员疏散计算机模型。狭义信息,即能被人员本身接受和作出反应可感知的信号,它的产生和传递对疏散过程有直观而显著的影响。而广义信息则是其进一步延伸,包括了疏散过程中各种具体行为和作用结果。为了更全面地模拟和再现疏散过程中人员行为,使用的模型引入了狭义的信息传播原理。该模型由4个子系统构成,即人员模型、信号模型、建筑模型和特殊场景模型,较为充分地考虑了火灾疏散中的关键因素。运用该模型不但可以对疏散中的人员特殊行为进行理论研究,而且可以为实际工程(如地铁站、体育场馆、教学楼、医院等高风险场所)进行疏散安全论证提供帮助。  相似文献   
237.
阐述了UT-2000B型微机防误装置在永安火电厂的技改背景,对装置原理、主要技术特点、操作异常处理及技改安装内容作了介绍,并提出了投运后应注意的问题。  相似文献   
238.
ABSTRACT. The critical role of political processes in water resource projects has recently been placed in a new perspective [Hall, 1970]. The “political hassle” period of institutional interaction which serves to resolve political conflicts over such aspects as organizational growth and survival, responsibility for economic liabilities, and responsibility for economic benefits, requires systematic analysis in order to improve our capability to implement water projects. Failure to properly assess the political aspects of a proposed water project may result in extensive delays with significant economic losses. The complexities associated with water use and re-use have created the need for new institutional arrangements which can more effectively function to implement policies and programs. One tool which has recently become available for the research investigator concerned with institutional interactions and political processes associated with water resource projects is the technique of computer simulation of such institutional interaction. In theory, this new approach will enable the investigator to assess the political feasibility or political acceptability of a proposed water project given existing institutional structures. Furthermore, the investigator has the opportunity to experiment with new and innovative institutional arrangements which may in turn enhance the political acceptability of a proposed project. The specific material presented within this paper reports upon the validation of an existing computer simulation model designed to replicate political interactions in resource allocation problems-including water resource problems. This validation effort is done by taking an actual water problem and comparing what the political simulation models predicts in terms of political outcomes with what actually takes place. The case study in question is the formulation and legislative development of the Michigan Bond Issue for Water Pollution Control.  相似文献   
239.
ABSTRACT A critical examination of single gage site, monthly streamflow statistical characteristics for two southern Illinois rivers, an Oklahoma river and a Texas river was made using a digital computer at Northwestern University. High flow variability for the rivers was evident in that, for the rivers tested, 8 to 11 months had coefficients of variation in excess of unity. The gamma distribution was not as efficient as the normal distribution for fitting power or logarithmic transforms of the historical monthly flow data (i.e., F1-0, F0-5, F0-25, Fa125, F0.085, and log F). No single transform to a normal distribution was adequate for all twelve monthly flows, since definite seasonal grouping patterns were found for the four rivers examined. The highly variable flow in the low-flow season(s) indicated much more skewness than was typical of the remainder of the year. For the low-flow seasons, the higher-root (smaller exponent) transforms were particularly useful. Flows were generated from a linear regression model of lag one utilizing two or more transforms for the twelve periods. The definite seasonal patterns found historically were reproduced quite well in the generated streamflows. The effect of a change in data transform from one season to the next was insignificant after one month. Thus the use of different transforms within the year did not bias the results from the linear regression model appreciably, but did help in reproducing the seasonal distribution pattern. The technique seems especially well suited for rivers with highly variable flows.  相似文献   
240.
This paper is an effort to establish a lower bound on the economic value of the Columbia and Snake Rivers to the State of Washington, so as to assess the economic consequences of diversion of waters of these rivers to other geographic regions. The uses recognized in this paper are for power generation and irrigation, although the dynamic-programming model constructed is capable of incorporating, with minor changes, returns from other uses of the rivers when the economic data can be obtained.  相似文献   
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