全文获取类型
收费全文 | 1827篇 |
免费 | 151篇 |
国内免费 | 27篇 |
专业分类
电工技术 | 47篇 |
综合类 | 7篇 |
化学工业 | 492篇 |
金属工艺 | 47篇 |
机械仪表 | 87篇 |
建筑科学 | 81篇 |
矿业工程 | 4篇 |
能源动力 | 132篇 |
轻工业 | 167篇 |
水利工程 | 31篇 |
石油天然气 | 37篇 |
无线电 | 165篇 |
一般工业技术 | 284篇 |
冶金工业 | 72篇 |
原子能技术 | 14篇 |
自动化技术 | 338篇 |
出版年
2024年 | 9篇 |
2023年 | 50篇 |
2022年 | 60篇 |
2021年 | 117篇 |
2020年 | 118篇 |
2019年 | 126篇 |
2018年 | 174篇 |
2017年 | 155篇 |
2016年 | 143篇 |
2015年 | 72篇 |
2014年 | 132篇 |
2013年 | 207篇 |
2012年 | 113篇 |
2011年 | 133篇 |
2010年 | 82篇 |
2009年 | 69篇 |
2008年 | 46篇 |
2007年 | 32篇 |
2006年 | 34篇 |
2005年 | 18篇 |
2004年 | 18篇 |
2003年 | 15篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 7篇 |
1999年 | 9篇 |
1998年 | 14篇 |
1997年 | 9篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有2005条查询结果,搜索用时 31 毫秒
1.
Tourajizadeh Hami Yousefzadeh Mahdi Khalaji Ali Keymasi Bamdad Mahdi 《International Journal of Control, Automation and Systems》2022,20(5):1671-1681
International Journal of Control, Automation and Systems - In this paper, a new controllable simulator is proposed and modeled by which, experimental tests of the aircraft’s models can be... 相似文献
2.
Amini Amir Jafari Azin Vafaei Mostafa Mahmoodian Mehrnoosh 《Journal of Materials Science: Materials in Electronics》2022,33(3):1293-1306
Journal of Materials Science: Materials in Electronics - The main weakness of polymer gas sensors is its stability. Here, we report stability enhancement of a 100 nm polypyrrole (PPy) thin... 相似文献
3.
4.
Maktabdar Oghaz Mahdi Maarof Mohd Aizaini Rohani Mohd Foad Zainal Anazida Shaid Syed Zainudeen Mohd 《Neural computing & applications》2019,31(6):1835-1853
Neural Computing and Applications - Texture analysis is devised to address the weakness of color-based image segmentation models by considering the statistical and spatial relations among the group... 相似文献
5.
The Journal of Supercomputing - Data center network virtualization is being considered as a promising technology to provide a performance guarantee for cloud computing applications. One important... 相似文献
6.
7.
DJ Conway MJ Holland RL Bailey AE Campbell OS Mahdi R Jennings E Mbena DC Mabey 《Canadian Metallurgical Quarterly》1997,65(3):1003-1006
Tumor necrosis factor alpha (TNF-alpha) may play a central role in the disease pathogenesis which occurs as a consequence of chlamydial infection. To investigate the importance of TNF-alpha gene promoter polymorphisms and TNF-alpha levels in tear fluid in scarring trachoma, a large matched-pair case-control study was performed in The Gambia. The -308A allele was present in a higher proportion of patients (28.4%) than controls (18.4%), with an increasing association for homozygotes (chi2 for trend, P = 0.032; allele frequency, 0.163 in patients and 0.099 in controls; chi2, P = 0.025). For the -238A allele, the association was similar but not significant. The disease association was highly significant when the number of either -308A or -238A sites in an individual was considered (P = 0.003). TNF-alpha promoter alleles are tightly linked to some HLA class I and II alleles, but multivariate analysis confirmed that the disease associations were independent of HLA, although a class I allele, A*6802, is also associated with disease. TNF-alpha was more frequently detected in tear samples from patients (27.6%) than from controls (15.9%), increasingly so for higher levels of detectable TNF-alpha (P = 0.015). Among patients, detectable TNF-alpha in tears was highly associated with the presence of ocular chlamydial infection (P < 0.001). The results indicate that TNF-alpha plays a major role in the tissue damage and scarring which occurs as a consequence of Chlamydia trachomatis infection. 相似文献
8.
9.
We consider multistage automatic transfer lines with unreliable stages, finite interstage buffer storages, and possible scrapping of workpieces. It is assumed that the first stage never idles and the last stage never becomes blocked. Assuming that uptimes and downtimes of a stage are geometrically distributed, an approximate model is developed to compute different performance measures of the transfer line. The results obtained through the approximate model are compared to the exact results for three-stage transfer lines and to simulation results for longer transfer lines. It is observed that the approximate results are good in almost all cases considered. 相似文献
10.
Tong Fang Mohsen A. Jafari Stephen C. Danforth Ahmad Safari 《Machine Vision and Applications》2003,15(2):63-75
This paper presents the concept of a process signature for the use of online signature analysis and defect detection in the layered manufacturing (LM) of ceramic sensors and actuators. To achieve the high quality of parts built by the fused deposition of ceramics (FDC), an online process-monitoring system is implemented to detect the processing defects. Using a process signature extracted from the image of a layer captured by the monitoring system, an ideal image is created that is then compared to the original image to detect and identify the defects. Some results of signature analysis and defect detection for single-material and multi-material parts are also presented.Received: 22 July 1999, Accepted: 21 October 2001, Published online: 29 October 2003
Correspondence to: Mohsen A. JafariThis work was supported by the Office of Naval Research under grant # N-0014-96-1-1175. Ref. US Patent # S-5738817, April 14, 1998. 相似文献