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361.
This paper summarizes some of the recent trends in domestic water use in both developed and developing countries, so as to better identify the principal factors influencing the demand. The focus is on the adoption of a more microapproach to demand forecasting, rather than the traditional use of overall averages, so as to move towards more cost effective and resource efficient supply schemes. An important aim of the paper is to alert designers of new water supply schemes in developing countries to the need to apply caution to the belief that per capita water use will continue to increase in tandem with the general economic development of the area being served, to the extent that it reaches the levels experienced in more developed countries. Survey data are presented from a range of locations to illustrate the trends in domestic water use for both connected households and community standpipes.  相似文献   
362.
Kalimantan Island is located in the Southeast Asia continental marginal tectono-magmatic mobile zone in the West Pacific Ocean, where the lithosphere of Earth is one of the most complicated tectonic mobile regions on the Earth since Meso-Cenozoic. Based on the geophysical data of the basement and deep structures, the stress field of mantle flow, the maximum principal stress field and geothermal flux, the crustal nature and geodynamical features of Kalimantan Island and adjacent areas were analyzed. Researches on geotectonic movement and evolution of Kalimantan and adjacent areas show that Southeast Asia continental margin crustobody was formed at about middle-late Triassic. In addition, the geotectonic units of the Kalimantan area were subdivided, and characteristics of their geotectonic evolution were discussed.  相似文献   
363.
Container flow information is a critical issue for port operators and liners to support their strategic planning and decision-making. This study uses artificial neural networks (ANNs) to predict container flows by considering GDP, interest rates, the value of export and import trade, the numbers of export and import containers and the number of quay cranes. ANNs are developed for data mining purposes, and the developed model can simultaneously predict container flows between the major ports of Asia. The forecasting results indicate that the prediction errors are relatively small in most selected ports, and thus shipping companies can use the container flow prediction model to make decisions concerning operations. The results can be further applied to the trend analysis of container flows among the major ports of Asia, and a community analysis of the containers was conducted for the purpose of supply chain management.  相似文献   
364.
A “policy as process” perspective is adopted to analyze the early period of water users associations (WUAs) in Uzbekistan (2000–2006). The article is based on extensive fieldwork (in 2005–2006) and analysis of policy and other relevant documents. It is shown that WUAs have a role and logic beyond water management and are used by the state as instruments with which to monitor and regulate “state-ordered” agricultural production. Through a state-centric policy process with room for local experimentation, the WUA was fit into the socio-political landscape of continued state control and the increased role of individualized risks and benefits.  相似文献   
365.
川东南地区志留系页岩含气量特征及其影响因素   总被引:1,自引:0,他引:1  
页岩含气量是页岩气勘探潜力评价、勘探有利区优选、资源量计算的重要指标,也是后期进行开发规划、气藏描述、储量计算的关键参数。为了探索影响页岩含气量的因素,应用统一的方法现场测量了四川盆地东南不同地区多口页岩气探井的含气量,通过对比分析其含气量特征,找到了不同页岩气探井的岩性、总有机碳含量、孔隙度、压力系数等参数与含气量的关系,归纳了影响页岩含气量的主要因素。结论认为,影响页岩含气量的因素可以分为两大类:(1)只在早期对含气量有影响的基础因素,主要为有机质类型、有机质丰度、岩性、黏土矿物含量等;(2)控制页岩含气量的关键因素是保存条件,构造样式和断裂发育程度是影响保持条件的主要因素。孔隙度、孔隙结构、压力系数等参数不是影响页岩含气量的因素,而是表征页岩含气量高低的指标性参数,因此在勘探中可以尝试通过孔隙度预测或压力预测来判断页岩的含气性。  相似文献   
366.
东南诸河区水资源综合规划概要   总被引:1,自引:0,他引:1  
叶寿仁  吴志平 《中国水利》2011,(23):121-123,104
按照全国统一部署,东南诸河区水资源综合规划在查清东南诸河区水资源及其开发利用现状、分析评价水资源和水环境承载能力的基础上,根据流域经济社会发展和生态环境保护对水资源的要求,针对区域工程型、水质型与资源型不同缺水问题,提出水资源合理开发、高效利用、优化配置、全面节约、有效保护和综合治理的布局及方案,促进区域资源环境和经济社会的协调发展,以水资源的可持续利用支撑经济社会的可持续发展.简要介绍了东南诸河区水资源形势、规划目标及供需分析、水资源配置及管理等规划主要成果.  相似文献   
367.
A sensor web is a collection of heterogeneous sensors which autonomously reacts to the observed environment. The SouthEast Alaska MOnitoring Network for Science, Technology, Education, and Research (SEAMONSTER) project has implemented a sensor web in partially glaciated watersheds near Juneau, Alaska, on the edge of the Juneau Icefield. By coupling the SEAMONSTER sensor web with digital earth technologies the scientific utility, education and public outreach efforts, and sensor web management of the project all greatly benefit. This paper describes the scientific motivation for a sensor web, the technology developed to implement the sensor web, the software developed to couple the sensor web with digital earth technologies, and demonstrates the SEAMONSTER sensor web in a digital earth framework.  相似文献   
368.
利用2002年12月到2016年11月的大气红外探测仪(Atmospheric infrared sounder, AIRS)卫星观测资料,分析了全球 和东亚地区(70~140E, 10~55N)CO2浓度的时空变化和季节分布特征,并与地面观测 资料进行了对比。结果表明: 1) AIRS反演的CO2资料与地表观测资料相关系数均在0.9以上,且年均值相对误差均 在1%以内。2)全球CO2年平均浓度从2003年的375.16 ml/m3增加到2016年的401.24 ml/m3, 年平均增长率约2.01 ml/m3;同期,东亚地区CO2平均浓度从2003年的375.13 ml/m3增加 到2016年的402.22 ml/m3,年增长率约为2.08 ml/m3,高于全球的年平均增长率。 在2010~2016年,北半球大部分地区CO2浓度增长率低于2003~2009年的增长率。CO2增幅较明显 的区域位于北半球高纬度地区如中西伯利亚和格陵兰岛等地上空。3)CO2分布存在明显的区域性,高值区主要位于 北半球的中高纬度地区;低值区主要位于青藏高原上空。在南半球,CO2浓度的高值区主要位于南美洲中纬度地区; 低值区主要出现在低纬度(0~20S, 50W~5E)的大西洋上空。在对流层中低层(4~6 km), AIRS反演的CO2浓度的季节变化特征准确性较高,特别在冬季,北半球大部分地区的CO2浓度随着时间 变化呈现先减小后增加的趋势。4)在东亚地区,CO2高值区位于中国北方地区,呈带状分布。  相似文献   
369.
The difference between aerosol optical depths (AODs) retrieved from the Multi-angle Imaging SpectroRadiometer (MISR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) is examined over mainland Southeast Asia from a spatial perspective. Though ideally the difference between these measurement methods should be small and randomly distributed over space, our analysis suggests that this difference has a strong negative relationship with MODIS AODs and tend to be spatially clustered. We quantify the spatial dependence in MISR/MODIS AOD differences and explore the extent to which the spatial patterns in these differences can be explained by variables that reflect the influence of physical environment and human activities. While these variables show a strong relationship with MISR/MODIS AOD differences, the results also suggest that further research is needed to fully understand the spatial dependence in these differences.  相似文献   
370.
Water flow patterns in the Mekong are changing because of on‐going rapid hydropower development triggered by economic growth. Of immediate concern are the current and proposed hydropower dams in the transboundary Srepok, Sesan and Srekong (3S) Rivers, which contribute up to 20% of the Mekong's annual flows, have a large potential for energy production and provide critical ecosystem services to the downstream Tonle Sap Lake and Mekong Delta. The objective of this paper is to determine how the operation of the proposed largest individual dams and cascade dam schemes in the 3S Rivers will affect flow regimes and energy production. Daily flows were simulated over 20 years using the Soil and Water Assessment Tool and HEC‐ResSim models for a range of dam development and operations scenarios. The development of all dams in the 3S basin under an operation scheme to maximize individual electricity production results in an average 98% increase in dry season flows at the 3S outlet. Over 55% of dry season flows changes are caused by seven proposed large dams, with the Lower Srepok 3 project causing the highest impact. The seven large dams will generate 33.0 GWh/day with a water volume of 17 679 x 106 m3, compared with the current and definite future dams generating 73.2 GWh/day with a much lower volume of 6616 x 106 m3. When a cascade of dams are operational, downstream dams with small reservoirs will produce more energy. However, the marginal increase in energy production from the development of additional dams in the 3S basin will decline rapidly relative to the required water storage increase,. Strategic decision‐making on the future of each large proposed dam in the 3S basin needs to be considered by local governments after understanding cumulative operation effects and with further consideration to the potential impact on downstream ecosystem productivity and livelihoods. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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