全文获取类型
收费全文 | 5875篇 |
免费 | 508篇 |
国内免费 | 313篇 |
专业分类
电工技术 | 287篇 |
综合类 | 377篇 |
化学工业 | 947篇 |
金属工艺 | 469篇 |
机械仪表 | 488篇 |
建筑科学 | 476篇 |
矿业工程 | 202篇 |
能源动力 | 172篇 |
轻工业 | 315篇 |
水利工程 | 144篇 |
石油天然气 | 375篇 |
武器工业 | 37篇 |
无线电 | 604篇 |
一般工业技术 | 697篇 |
冶金工业 | 331篇 |
原子能技术 | 69篇 |
自动化技术 | 706篇 |
出版年
2024年 | 8篇 |
2023年 | 100篇 |
2022年 | 153篇 |
2021年 | 260篇 |
2020年 | 198篇 |
2019年 | 156篇 |
2018年 | 164篇 |
2017年 | 173篇 |
2016年 | 142篇 |
2015年 | 201篇 |
2014年 | 306篇 |
2013年 | 359篇 |
2012年 | 374篇 |
2011年 | 392篇 |
2010年 | 365篇 |
2009年 | 330篇 |
2008年 | 315篇 |
2007年 | 304篇 |
2006年 | 318篇 |
2005年 | 283篇 |
2004年 | 186篇 |
2003年 | 205篇 |
2002年 | 228篇 |
2001年 | 208篇 |
2000年 | 167篇 |
1999年 | 190篇 |
1998年 | 109篇 |
1997年 | 108篇 |
1996年 | 78篇 |
1995年 | 87篇 |
1994年 | 39篇 |
1993年 | 45篇 |
1992年 | 36篇 |
1991年 | 20篇 |
1990年 | 14篇 |
1989年 | 23篇 |
1988年 | 16篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有6696条查询结果,搜索用时 15 毫秒
1.
2.
为了探讨在安卓平台上构建医用图像采集系统的开发个案,分析通过以智能手机、平板电脑为核心安卓设备通过拍照获得化验单数据后进行文本识别并提交智慧医疗系统的解决方案。本文首先通过二值化算法形成低阈值图像数据,使用卷积神经元网络算法对文本进行逐一识别,使用K-means算法对识别后的单字文本进行字段记录值的整合并形成元数据库服务于其他智慧医疗系统模块。在使用9000组数据对神经元网络进行前期训练的前提下,该系统的识别准确率达到了99.5%以上。本系统具有一定的可行性,对未来智慧医疗的系统开发有实践意义。 相似文献
3.
本文提出一种基于实时几何测距的船桥主动防撞方法。该方法对船的改动量甚微,仅需维持多项距离矩阵,通过告警逻辑矩阵进行展示与告警,能起到很好的船桥防撞提示效果。 相似文献
4.
5.
Wei Wang Lingjuan Zhao Dan Lu Jianping Yao Weiping Huang Yong Liu Brent Little 《半导体学报》2021,42(4):1-2
The past 20 years have witnessed the rapid growth of photonic integration circuits(PIC)technology,which has been warmly embraced by both academia and the industry.Powered by the advanced development in material growth,processing,and design capability,the PIC technology now covers multiple material platforms,including III–V(InP,GaAs),silicon,silica,lithium niobate on insulator(LNOI)polymer,etc.The integration level has evolved from a single functional device to thousands of components on-chip.The increase in the performance and the complexity of the PICs have become an energetic booster for communication and information technology. 相似文献
6.
The capture of particles by charged droplets was simulated by considering the electrostatic interactions of droplet-droplet and droplet-particle. The results indicate that the electrostatic repulsion between droplets leads to a dynamic accumulation mode of particles. However, the droplet spacing has an insignificant effect on the capture efficiency when the electrostatic deposition predominates. The increase of droplet charge remarkably improves the capture efficiency, in which the capture of fine particles accounts for the largest proportion. Compared to the droplet charge, the droplet size shows a limited improvement in the capture efficiency. Reducing the droplet velocity prolongs the capture time instead of enhancing the capture capacity per unit time, thereby improving capture efficiency. 相似文献
7.
Wei Zuo Le Ma Yu Lu Shu-yong Li Zhiqiang Ji Min Ding 《Metals and Materials International》2018,24(6):1346-1358
A novel additive manufacturing method with TIG–MIG hybrid heat source was applied for fabricating 5356 aluminum alloy component. In this paper the microstructure evolution, mechanical properties and fracture morphologies of both as-deposited and heat-treated component were investigated, and how these were affected by different heat-treated temperature. The as-deposited microstructure showed dominant equiaxed grains with second phase, and the size of them is coarse in the bottom region, medium in the middle region and fine in the top region owing to different thermal cycling conditions. Compared with as-deposited microstructure, the size of grain becomes large and second phases gradually dissolve in the matrix as heat-treated temperature increase. Different microstructures determine the mechanical properties of component. Results show that average ultimate tensile strength enhances from 226 to 270 MPa and average microhardness increases from 64.2 to 75.3 HV0.1 but ductility decreases from 33 to 6.5% with heat-treated temperature increasing. For all components, the tensile properties are almost the same in the vertical direction (Z) and horizontal direction (Y) due to equiaxed grains, which exhibits isotropy, and the mechanisms of these are analyzed in detailed. In general, the results demonstrate that hybrid arc heat source has the potential to fabricate aluminum alloy component. 相似文献
8.
9.
World Wide Web - In recent years, short text topic modeling has drawn considerable attentions from interdisciplinary researchers. Various customized topic models have been proposed to tackle the... 相似文献
10.
Xu Q. J. Zuo C. S. Liu D. Y. Shi W. Z. 《Theoretical Foundations of Chemical Engineering》2018,52(6):1039-1044
Theoretical Foundations of Chemical Engineering - Troxerutin supported palladium (TXT-Pd) catalyst was prepared readily by using one-step synthetic method. As-fabricated TXT-Pd catalyst was... 相似文献