全文获取类型
收费全文 | 4945篇 |
免费 | 278篇 |
国内免费 | 64篇 |
专业分类
电工技术 | 137篇 |
综合类 | 81篇 |
化学工业 | 945篇 |
金属工艺 | 127篇 |
机械仪表 | 116篇 |
建筑科学 | 236篇 |
矿业工程 | 419篇 |
能源动力 | 146篇 |
轻工业 | 594篇 |
水利工程 | 558篇 |
石油天然气 | 112篇 |
武器工业 | 12篇 |
无线电 | 191篇 |
一般工业技术 | 456篇 |
冶金工业 | 490篇 |
原子能技术 | 46篇 |
自动化技术 | 621篇 |
出版年
2023年 | 26篇 |
2022年 | 137篇 |
2021年 | 154篇 |
2020年 | 113篇 |
2019年 | 109篇 |
2018年 | 115篇 |
2017年 | 122篇 |
2016年 | 122篇 |
2015年 | 155篇 |
2014年 | 171篇 |
2013年 | 276篇 |
2012年 | 257篇 |
2011年 | 285篇 |
2010年 | 229篇 |
2009年 | 194篇 |
2008年 | 199篇 |
2007年 | 166篇 |
2006年 | 132篇 |
2005年 | 132篇 |
2004年 | 272篇 |
2003年 | 349篇 |
2002年 | 403篇 |
2001年 | 335篇 |
2000年 | 91篇 |
1999年 | 67篇 |
1998年 | 133篇 |
1997年 | 96篇 |
1996年 | 46篇 |
1995年 | 42篇 |
1994年 | 56篇 |
1993年 | 45篇 |
1992年 | 22篇 |
1991年 | 13篇 |
1990年 | 16篇 |
1989年 | 19篇 |
1988年 | 19篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 15篇 |
1984年 | 11篇 |
1983年 | 11篇 |
1982年 | 17篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 5篇 |
1977年 | 11篇 |
1976年 | 19篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1972年 | 4篇 |
排序方式: 共有5287条查询结果,搜索用时 31 毫秒
131.
Mikko Kurimo Seppo Enarvi Ottokar Tilk Matti Varjokallio André Mansikkaniemi Tanel Alumäe 《Language Resources and Evaluation》2017,51(4):961-987
One particular problem in large vocabulary continuous speech recognition for low-resourced languages is finding relevant training data for the statistical language models. Large amount of data is required, because models should estimate the probability for all possible word sequences. For Finnish, Estonian and the other fenno-ugric languages a special problem with the data is the huge amount of different word forms that are common in normal speech. The same problem exists also in other language technology applications such as machine translation, information retrieval, and in some extent also in other morphologically rich languages. In this paper we present methods and evaluations in four recent language modeling topics: selecting conversational data from the Internet, adapting models for foreign words, multi-domain and adapted neural network language modeling, and decoding with subword units. Our evaluations show that the same methods work in more than one language and that they scale down to smaller data resources. 相似文献
132.
维吾尔文地理信息服务的研究与应用的匮乏,使维吾尔用户很难享受基于本民族语言的地理信息服务。该文以新疆动态天气图文信息服务为例,提出了一种面向维文网站的WebGIS服务解决方案。方案首先通过集成免费Google Maps API地图服务和实时免费Yahoo Weather RSS天气信息,制作新疆县域维吾尔文天气信息服务模块;其次,将该模块作为引用对象,根据用户对动态天气图文信息服务框架大小和位置的设定,个性化地嵌入到任意维吾尔文大众网站中,使更广大的维吾尔用户享受WebGIS带来的信息服务。该研究推动了WebGIS在维吾尔语语境的新应用,为新疆各族群众提供了便捷动态天气图文信息服务。 相似文献
133.
134.
Lossless convexification of a class of optimal control problems with non-convex control constraints 总被引:2,自引:0,他引:2
We consider a class of finite time horizon optimal control problems for continuous time linear systems with a convex cost, convex state constraints and non-convex control constraints. We propose a convex relaxation of the non-convex control constraints, and prove that the optimal solution of the relaxed problem is also an optimal solution for the original problem, which is referred to as the lossless convexification of the optimal control problem. The lossless convexification enables the use of interior point methods of convex optimization to obtain globally optimal solutions of the original non-convex optimal control problem. The solution approach is demonstrated on a number of planetary soft landing optimal control problems. 相似文献
135.
136.
蒙古文整词计算机生成理论研究 总被引:1,自引:0,他引:1
采用面向对象方法,模拟传统蒙古文整词各种形式构成机理,提出了几种蒙古语整词计算机生成数据模型。文章主要依据整词计算机生成三种模型,探讨了传统蒙古文整词计算机最优化生成理论所涉及的精确度、时间复杂度、空间复杂度三项基本要素以及最优化生成必须考虑的整词复杂特征载荷与一体化合一计算知识表示方法和计算结构,证明了“B - J - T= W”数据模型是传统蒙古文整词计算与生成最优化对象模型。 相似文献
137.
提出一种解决PACT01一种结合动态可编程逻辑阵列(DPGA)的处理器的新型体系结制中cache的一致性与同步性问题的算法,并且解决多线程支持的快速上下文切换及快速用户级操作问题。存储器替换机制是解决cache的一致性问题及当cache未命中时从局部或远程存储器到cacbe存储器的数据替换问题的一种硬件实现方法,产生冲突的原因是由于多线程并行的写入/读取的位置相同和读或写的位置相同。文中选择的是相联映射策略,同时也选择了最少最近使用LRU算法,即在cache未命中时替换最少最近使用的参考块,为实现LRU算法设置了与每块相对应的计数器。 相似文献
138.
A novel approach of combining flexible molecular docking, GRID molecular interaction fields, analysis of ligand-protein hydrogen bond interactions, conformational energy penalties and 3D-QSAR analysis was used to propose a binding mode in the dimer interface of the iGluR2 receptor for the biarylpropylsulfonamide class of positive allosteric AMPA modulators. Possible binding poses were generated by flexible molecular docking. GRID molecular interaction fields of the binding site, ligand-protein hydrogen bonding interactions and conformational energy penalties were used to select the most likely binding mode. The selected binding poses were subjected to a 3D-QSAR analysis using previously published activity data. The resulting model (2 LVs, R2=0.89, q2=0.61) predicted the activities of the compounds in the test set with a standard deviation on error of prediction of 0.17. The proposed binding mode was validated by interpretation of the PLS-coefficient regions from the 3D-QSAR analysis in terms of interactions between the receptor and the modulators. 相似文献
139.
Digital microfluidic design and optimization of classic and new fluidic functions for lab on a chip systems 总被引:2,自引:2,他引:0
Yves Fouillet Dorothée Jary Claude Chabrol Patricia Claustre Christine Peponnet 《Microfluidics and nanofluidics》2008,4(3):159-165
This paper deals with microfluidic studies for lab-on-a-chip development. The first goal was to develop microsystems immediately
usable by biologists for complex protocol integrations. All fluid operations are performed on nano-liter droplet independently
handled solely by electrowetting on dielectric (EWOD) actuation. A bottom-up architecture was used for chip design due to
the development and validation of elementary fluidic designs, which are then assembled. This approach speeds up development
and industrialization while minimizing the effort in designing and simplifying chip-fluidic programming. Dispensing reproducibility
for 64 nl droplets obtained a CV below 3% and mixing time was only a few seconds. Ease of the integration was demonstrated
by performing on chip serial dilutions of 2.8-folds, four times. The second part of this paper concerns the development of
new innovative fluidic functions in order to extend EWOD-actuated digital fluidics’ capabilities. Experiments of particle
dispensing by EWOD droplet handling are reported. Finally, work is shown concerning the coupling of EWOD actuation and magnetic
fields for magnetic bead manipulation. 相似文献
140.
描述了蚁群系统算法求解物流配送路径问题的过程;通过仿真实验分析了蚁群系统算法中各参数对物流配送路径问题求解的影响. 相似文献