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261.
Richard A. Andrews Richard R. Weyrick 《Journal of the American Water Resources Association》1973,9(2):258-272
ABSTRACT A linear programming model for a river basin was developed to include almost all water-related economic activity both for consumers and producers. The model was so designated that the entire basin or basin sub-division could be analyzed. The model included seven sectors, nine objective function criteria, and three river-flow levels. Economic basis for conflicts among sectors over incidence of cost allocation and level of economic activity can be traced to some chosen objective. The disposal of untreated household waste water, particularly from the rural household, directly into the river was consistent with maximizing net benefits and minimizing costs. The optimum resource allocation, water-treatment plants, farms and industry activities would change with flow level. For each of the three industries analyzed separately, paper, wool and tanning, public treatment of industrial waste water was the optimal treatment process in one or more of the solutions. Lake shoreline was the dominant feature determining lake-resource valuation. Implied capital value varied from $126 per shoreline foot to over $250 depending on discount rate. Implied prices on lake surface ranged from $42 to $147 per acre. Strong economic forces encouraged small lot sizes for vacation cottages. 相似文献
262.
263.
Lamberto C. Palencia 《Journal of the American Water Resources Association》1988,24(2):275-279
ABSTRACT: An econometric demand function is estimated for residential water use in Metropolitan Manila. Regression results using annual time series data from 1970 to 1981 show that residential water consumption responds to changes in economic variables. Residential demand showed an income (household) elasticity of 0.542 and a combined price elasticity of -0.287. Implications for planning and management are discussed. 相似文献
264.
It is not uncommon for the carrying capacity for congestible facilities to be estimated before the allocation method is known. This paper shows how efficient capacity differs between two competing resource allocation mechanisms, one which is efficient (price) and one which is fair (lottery). The welfare theoretic implications of adopting lottery allocation rather than price allocation are illustrated from the perspectives of economic efficiency and the benefits obtained by resource users and suppliers. It is found that risk-neutral resource users will always prefer lottery allocation to price allocation. While price allocation is efficient, it is never in risk-neutral resource users» interests to have price allocation imposed. Conclusions are tested using a linear constant crowding demand function, in which case it is found that the efficient capacity for lottery rationing exceeds the efficient capacity where price is to be used to allocate a congestible resource. Objectives may be better met by joint use of allocation mechanisms, the implications of which are investigated using the linear demand model. 相似文献
265.
Mark E. Thompson Herbert H. Stoevener 《Journal of the American Water Resources Association》1983,19(6):889-896
ABSTRACT: An implicit price model relating residential lot value to price determining characteristics of land is developed to measure the benefits of a structural flood control project. Special attention is given to the selection of relevant price determining characteristics of residential lots. An implicit price equation is estimated for both the with and without project conditions. Flood damages are quantified through the use of a dummy variable indicating a flood plain location. The analysis shows that annual flood damages were reduced by $15,275. 相似文献
266.
杨学亮 《中国环境管理干部学院学报》2007,17(1):56-58,64
地价与房价作为房地产市场的两个重要指标,其水平高低对房地产市场的正常、有序发展起者重要作用。房价与地价在一定范围内、一定条件下相互作用,相互影响。正确分析和处理房价与地价的关系,促进房地产业健康发展,可采取以下措施:土地交易信息公开、透明;土地及时开发,及时入市;加强对土地市场供需结构的宏观调控和经济适用房、廉租房体系的建设等。 相似文献
267.
268.
M. Kashif Gill Mariush W. Kemblowski Mac McKee 《Journal of the American Water Resources Association》2007,43(4):1004-1015
Abstract: A hybrid data assimilation (DA) methodology that combines two state‐of‐the‐art techniques, support vector machines (SVMs) and ensemble Kalman filter (EnKF), is applied for soil moisture DA in this work. The SVM methodology provides a statistically sound and robust approach to solving the inverse problem, and thus to building statistical models. EnKF is an extension of the Kalman Filter (KF), a well‐known tool in prediction updating. In the present research, ground measurements were used to build a SVM‐type soil moisture predictor. Subsequent observations and their statistics were assimilated to update predictions from the SVM model by coupling it with EnKF. In this way, both model predictions and ground data, as well as their statistics, are fused thus minimizing the prediction error and making the predictions and observations statistically consistent. The results are shown for two approaches; one in which update is done at every time step and the other which assumes that data is only available at alternate time steps (in window of 10 time steps) and hence update is performed at those occasions. The SVM‐EnKF coupling is shown to improve soil moisture forecasts in an example using data from the Soil Climate Analysis Network site at Ames, Iowa. 相似文献
269.
地理信息系统(GIS)平台采购成本高、信息发布缺乏有效通用方法,使利用其进行二次开发的模式难以符合一些应急救援信息系统建设实际需要。万维网联盟制定的可缩放矢量图形(SVG)为解决这些问题提供了契机。在评价SVG作为下一代网络矢量图形开放标准的优势基础上,对如何以SVG为基础构建应急救援网络地理信息系统(WebGIS)进行了深入分析;介绍了用SVG设计应急救援专题电子地图的特色与实现方法,然后针对该专题对基于SVG的WebGIS架构进行了剖析与优化设计,并引入了重大危险源元数据库与应急救援方法库两个概念,最后给出一个重大危险源应急救援信息系统的框架。以该技术建立的应急救援WebGIS无平台依赖性,网络发布与交互便捷,开发具有伸缩性,适合不同层次应用需求。 相似文献
270.
应用DEA方法评价污水处理厂相对效率,并将评价结果用于污水处理定价,得到了基于DEA方法的污水处理定价模型。该模型克服了现有定价模型的不足,体现了政府对污水处理厂生产效率的要求,能够促使企业提高效率并降低成本。 相似文献