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111.
该文提出一种自适应小波包图像压缩感知方法。该方法选用小波包变换分解图像,基于数学期望和信息熵分析各个小波包系数块的属性,自适应地将其划分为低频信号、无价值信号、特殊处理信号和压缩感知处理信号等4种信号类型,再针对不同的信号类型设计对应的处理方法,适应不同特征的图像。通过此种方法,在图像压缩感知过程中,可以根据不同图像和小波包系数块自适应地选取采样值,来提高压缩感知质量。实验结果表明该文提出的自适应小波包图像压缩感知方法在相同采样值的前提下,不仅提高了图像的重构质量,同时也降低了算法的计算复杂度和所需存储空间。 相似文献
112.
In five experiments, rats received conditioning of either moderately attractive or moderately aversive flavors using either a strongly negative lithium chloride (LiCl) or a strongly positive Polycose as the reinforcer. In each case, testing was done with a compound of the two moderately valued stimuli to determine the amount of associative change produced by the pairing. In both within-subject and between-subjects designs, the amount of associative change was greater for a signal whose moderate value was opposite in valence from that of the reinforcer. This suggests that, like learned stimulus value, inherent stimulus value can modulate further associative learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Walking through CS AKTive Space: a demonstration of an integrated Semantic Web application 总被引:1,自引:0,他引:1
Nigel R. Shadbolt Nicholas Gibbins Hugh Glaser Stephen Harris m.c. schraefel 《Journal of Web Semantics》2004,1(4):415-419
We describe CS AKTive Space, an integrated semantic web application and winner of the 2003 Semantic Web Challenge [http://www.challenge.semanticweb.org/]. A demonstration of the application is available at http://cs.aktivespace.org/. CS AKTive Space represents and integrates a wide range of heterogenous resources representing the computer science domain in the UK; it supports the exploration of patterns and implications inherent in the content and exploits a variety of services, visualisations and multidimensional representations to support questions like who is working with whom, where are there geographical concentrations in funding or research area, who are the most significant researchers in an area. We briefly show how this demonstration illustrates a number of substantial challenges for the Semantic Web. These include problems of referential integrity, tractable inference and interaction support. We review our approaches to these issues and discuss relevant related work. 相似文献
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电能表是电力企业收取电费的直接工具,其性能稳定性、测量准确性和可靠性关系到电力部门和用户之间的结算问题。现有的电能表集抄模式还存在着谐波干扰、人工和无线网络的传输质量与速率等问题。 相似文献
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A chemimechanical (CM) pretreatment method was devised, wherein wood chips are acid-treated to weaken the physical structure then disc-refined to produce a fibrous substrate. CM pretreatment was directly compared with a common dilute acid (DA) pretreatment method, wherein wood is mechanically downsized to a powder or fiber substrate and then acid-treated. It was hypothesized that the CM pretreatment sequence would reduce the energy required for size reduction and increase enzymatic digestibility of the pretreated substrate. By treating wood chips in a dilute sulfuric acid liquor before the mechanical downsizing step, the net specific energy (NSE) of disc-refining was reduced by up to 95%. At the optimal acid treatment and disc-refining conditions determined within this work, CM pretreatment could produce a highly digestible lignocellulose substrate (95% cellulose conversion) while requiring less than 100 kWh/tonne od NSE for mechanical downsizing. A comparison of CM and DA pretreated hardwood revealed that CM pretreatment produced a significantly more digestible substrate than DA pretreatment. Differences in the digestibility of CM and DA pretreated substrates were attributed to differences in physical structure. CM pretreatment produced a substrate that consisted primarily of single fibers and small fiber bundles, while DA pretreatment produced larger fiber bundles. Furthermore, the CM pretreated substrate had a more accessible pore structure, and an altered distribution of surface lignin. 相似文献
118.
分子印迹膜SPR传感器检测氯磺隆的方法 总被引:1,自引:0,他引:1
研究使用了中国科学院电子学研究所自行研制的高灵敏度单通道SPR分析仪和进样装置,仪器为棱镜耦合型SPR传感器结构,其检测角度范围是40°~70°,折射率检测范围为1.04~1.47,谐振角的精度在0.001°。适用于SPR分析仪的分子印迹芯片采用PVC-MIP共聚膜法制备,SPR角度扫描结果表明,200nm以下厚度芯片具有较好的SPR吸收特性。以氯磺隆为模板的分子印迹膜与不加氯磺隆的分子印迹膜对比实验发现前者具有特异性结合的能力。实验对浓度0.1,0.2,0.5和1μg/mL的氯磺隆进行了SPR定点检测,这四种浓度氯磺隆的折射率响应信号满足线性关系,相关系数R=0.996 4。实验中对低浓度的氯磺隆进行反复检测,检测到50ng/mL的氯磺隆,满足农残检测的要求。 相似文献
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针对罐区无控制系统,所有工作手动完成,基础条件较差以及原始调和方式存在诸多问题,提出了一种基于DCS的汽油在线调合系统的设计方法,详细介绍了系统的选型方案、调和技术方案以及软件设计,阐述了汽油在线调合控制系统的原理特点和实现过程,系统经投用后,极大地提高了油品调合的自动化程度,取得了很好的经济效益。 相似文献