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31.
基于Ad hoc网络节点剩余电量和位置信息,为降低路由发现延时和延长网络生存寿命、充分利用网络带宽、存储及计算等资源,遵循网络负载均衡原则提出了基于位置与剩余电量的多路路由算法.通过构建算法模型,论证了节点剩余电量与位置对路由发现延时、稳定性与可靠性的影响.经NS2仿真试验表明该协议的节点利用率一般在75%左右,具有较好的综合性能,比较适用于节点频繁移动的Ad hoc动态网络环境. 相似文献
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研究了带随机利率的双二项风险模型的破产问题,得到了终极破产概率的上界、描述破产严重程度的破产前盈余分布和破产赤字的联合分布的递推公式,进而得到了终极破产概率、破产前盈余和破产瞬时盈余满足的积分方程. 相似文献
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Results of a study on the nitrogen flows in the Netherlands are presented for three different years. The details given for 1995 are preliminary. The data are derived from a material balance sheet investigation. The objective of the study is to present a complete, integrated and accurate overview of nitrogen losses from the anthropogenic nitrogen cycle in the country with respect to present and possible future nitrous oxide emissions. Losses are analyzed in terms of economic sources and the recipient environmental compartments. The nitrogen losses account for about 25% of the total nitrogen input in the anthropogenic nitrogen cycle. Most of the losses occur in agriculture (67%), whereas industry, traffic and households each contribute about 10% to the total nitrogen loss. About 15% of the total nitrogen input in the national economy ends up in the environment, where it gives rise to adverse effects as the eutrophication of fresh surface water and the contamination of ground water with nitrate. A comparison of the results for different years shows that little progress has been made in emission reductions so far. Ammonia emissions have been reduced, but at the expense of an increase of the nitrogen input to agricultural soils. 相似文献
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Through energy efficiency measures, it is possible to reduce heat surplus in the pulp and paper industry. Yet pulp and paper mills situated in countries with a heat demand for residential and commercial buildings for the major part of the year are potential heat suppliers. However, striving to utilize the heat within the mills for efficient energy use could conflict with the delivery of excess heat to a district heating system. As part of a project to optimize a regional energy system, a sulfate pulp mill situated in central Sweden is analyzed, focusing on providing heat and electricity to the mill and its surrounding energy systems. An energy system optimization method based on mixed integer linear programming is used for studying energy system measures on an aggregated level. An extended system, where the mill is integrated in a regional heat market (HM), is evaluated in parallel with the present system. The use of either hot sewage or a heat pump for heat deliveries is analyzed along with process integration measures. The benefits of adding a condensing unit to the back-pressure steam turbine are also investigated. The results show that the use of hot sewage or a heat pump for heat deliveries is beneficial only in combination with extended heat deliveries to an HM. Process integration measures are beneficial and even increase the benefit of selling more heat for district heating. Adding a condensing turbine unit is most beneficial in combination with extended heat deliveries and process integration. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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蒋利龙 《昆明理工大学学报(自然科学版)》1999,24(1):36-38
通过对光电测距仪测剩余 常数的性质与构成要素的分析,认为剩余常数本身及其检测值均具有随机性。 相似文献
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研制了一种结构简单、分水效率高的全自动油水分离器,介绍了其原理和设计计算方法。该分水器能实现水多出水、油多出油的连续排放,结合排出水的称量、记录、报警,有利于实现树脂生产反应深度、速度和终点提示,提高树脂生产装置的自动化水平。 相似文献
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