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排序方式: 共有162条查询结果,搜索用时 15 毫秒
41.
利用RBF神经网络,建立了阿拉尔垦区需水量预测模型。选取农业用水灌溉定额、工业用水重复利用率、城镇生活人均日需水量、农村生活人均日需水量作为模型输入,农业、工业、城镇生活、农村生活需水量作为输出。将2001—2007年用水量数据作为训练样本,用2008—2009年用水量数据对模型进行检验。在农业、工业、城镇生活、农村生活4类需水量中,2009年工业需水量预测的相对误差最大,为-16.24%,总需水量的最大误差仅为1.80%,取得了较满意的结果,表明RBF神经网络模型用于该区需水量预测是可行的。 相似文献
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ERDAS IMAGINE在采煤沉陷地复垦土方量计算中的应用 总被引:2,自引:0,他引:2
根据采煤沉陷地复垦施工工艺的特点,提出一种利用ERDAS IMAGINE遥感图像处理软件实现土方量自动计算的方法,为采煤沉陷地复垦的规划设计、总投资控制和资金分配提供准确的依据。介绍了该方法的计算原理和计算步骤。 相似文献
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为探讨黄土区露天煤矿复垦土壤剖面有机碳的动态变化,以山西平朔露天煤矿排土场不同复垦阶段的耕地、林地和草地为研究对象,通过野外分层采集土样,探讨了不同复垦方向土壤有机碳含量的剖面分布特征及其与土壤pH值、全氮和w(C/N)的相关关系。结果表明:土壤有机碳的剖面分布随土壤深度和复垦方向的变化而变化,不同复垦方向土壤有机碳的垂直分布表现出一定的规律性,即随着土层深度的增加而逐渐递减;与未复垦的排土场相比,复垦2 a和18 a的耕地表层土壤有机碳含量分别增加22.73%和46.06%,复垦18 a和22 a的林地土壤有机碳含量分别增加38.86%和29.55%,复垦14 a的草地土壤有机碳含量增加30.96%,而复垦18 a的草地土壤有机碳含量变化不大;矿区3种复垦方向土壤有机碳含量整体表现为:林地>耕地>草地;复垦后的耕地土壤有机碳与全氮含量之间有显著的正相关性,相关系数R=0.642,林地和草地土壤有机碳含量与全氮之间有极显著的正相关性,相关系数R≥0.812;不同复垦方向土壤有机碳与w(C/N)的相关性都极为显著,相关系数≥0.679;耕地和林地土壤有机碳含量与pH具有明显的负相关性,相关系数分别为-0.685和-0.723,而草地土壤有机C含量与土壤pH没有明显的相关性。本研究可为黄土区露天煤矿排土场土地复垦与生态重建提供一定的借鉴和参考。 相似文献
46.
Vijay P. Singh Donald K. Frevert Jeffrey D. Rieker Verne Leverson Susan Meyer Steffen Meyer 《Canadian Metallurgical Quarterly》2006,132(2):98-103
The hydrologic modeling inventory developed at the Bureau of Reclamation and posted at its website ?http://www.usbr.gov/pmts/rivers/hmi? is described. The inventory comprises a large number of state-of-the-art watershed models developed by government (federal, state, and local) agencies, universities, and private companies in the United States and elsewhere. This inventory is among the first of its kind and is useful not only for modelers but water resources planners and managers. 相似文献
47.
A strip mill roll shaft failure was investigated. The investigation revealed that the fatigue strength of the shaft had been
compromised by a combination of several factors that included: inadequate fillet radius size, the use of dissimilar filler
materials to rebuild the shaft surface, the presence of slag inclusions at the weld/alloy interface, and machining defects
on the shaft surface. Such failures have occurred repeatedly, and this paper presents a case study investigating the cause
of the problem and discusses possible remedial measures to prevent similar occurrences. 相似文献
48.
The paper discusses the problems of ash disposal from coal combustion in two large coal-mining regions in India. Compared
with the United States, India produces some three times the amount of coal ash per million metric tonnes of domestically produced
coal, 95% of which is sluiced into gigantic slurry ponds located near urban areas and occupying vast amounts of premium land.
The Jharia Coalfield produces some 30 million tonnes/year of ash and contains the world's largest complex of underground coal-mine
fires, occupying an aggregate surface area of about 10 km2 above which the land surface is extremely degraded. Similarly, the Singrauli Coalfield suffers from the environmental effects
of open-cast mining, spoil heaps and an enormous coal combustion ash disposal problem. Ash haulback is proposed as an efficient,
cost-effective way of removing significant quantities of ash from the surface/pond disposal and placing it in open-cast and
underground mines. In addition to contributing to the control of mine fires and subsidence, it is suggested that this would
have numerous beneficial effects in terms of the reclamation of poor-quality/degraded land for sustainable, productive use
and the reduction of harmful emissions and substances in populated areas.
Received: 26 October 1999 · Accepted: 27 April 2000 相似文献
49.
Selection of optimal land uses for the reclamation of surface mines by using evolutionary algorithms
《矿业科学技术学报(英文版)》2017,27(3):491-498
A methodology for the selection of the optimal land uses of the reclamation of mined areas is proposed. It takes into consideration several multi-nature criteria and constraints, including spatial constrains related to the permissible land uses in certain parts of the mined area. The methodology combines desirability functions and evolution searching algorithms for selection of the optimal reclamation scheme. Its application for the reclamation planning of the Amynteon lignite surface mine in Greece indicated that it handles effectively spatial and non-spatial constraints and incorporates easily the decision-makers preferences regarding the reclamation strategy in the optimization procedure. 相似文献
50.