全文获取类型
收费全文 | 92209篇 |
免费 | 7927篇 |
国内免费 | 4176篇 |
专业分类
电工技术 | 5870篇 |
技术理论 | 2篇 |
综合类 | 5889篇 |
化学工业 | 14336篇 |
金属工艺 | 5033篇 |
机械仪表 | 5288篇 |
建筑科学 | 6883篇 |
矿业工程 | 1885篇 |
能源动力 | 2715篇 |
轻工业 | 7354篇 |
水利工程 | 1853篇 |
石油天然气 | 3966篇 |
武器工业 | 682篇 |
无线电 | 12164篇 |
一般工业技术 | 11816篇 |
冶金工业 | 4639篇 |
原子能技术 | 1051篇 |
自动化技术 | 12886篇 |
出版年
2024年 | 414篇 |
2023年 | 1467篇 |
2022年 | 2801篇 |
2021年 | 3781篇 |
2020年 | 2636篇 |
2019年 | 2198篇 |
2018年 | 2464篇 |
2017年 | 2900篇 |
2016年 | 2526篇 |
2015年 | 3509篇 |
2014年 | 4535篇 |
2013年 | 5758篇 |
2012年 | 6131篇 |
2011年 | 6844篇 |
2010年 | 5916篇 |
2009年 | 5697篇 |
2008年 | 5634篇 |
2007年 | 5382篇 |
2006年 | 5142篇 |
2005年 | 4199篇 |
2004年 | 2858篇 |
2003年 | 2365篇 |
2002年 | 2383篇 |
2001年 | 2040篇 |
2000年 | 1928篇 |
1999年 | 1956篇 |
1998年 | 1838篇 |
1997年 | 1584篇 |
1996年 | 1421篇 |
1995年 | 1193篇 |
1994年 | 930篇 |
1993年 | 764篇 |
1992年 | 608篇 |
1991年 | 465篇 |
1990年 | 387篇 |
1989年 | 302篇 |
1988年 | 252篇 |
1987年 | 183篇 |
1986年 | 153篇 |
1985年 | 139篇 |
1984年 | 101篇 |
1983年 | 75篇 |
1982年 | 68篇 |
1981年 | 59篇 |
1980年 | 53篇 |
1979年 | 35篇 |
1978年 | 32篇 |
1977年 | 32篇 |
1976年 | 54篇 |
1973年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Haijun Fang Zongli Lin 《Automatic Control, IEEE Transactions on》2006,51(7):1177-1184
In this note, we revisit the problem of global practical stabilization for planar linear systems subject to actuator saturation and input additive disturbances. A parameterized linear state feedback law is designed such that, by tuning the value of the parameter, all trajectories of the closed-loop system converge to an arbitrarily small neighborhood of the origin in a finite time and remain in there. 相似文献
12.
Zhiping Lin Xu L. Bose N.K. 《IEEE transactions on circuits and systems. I, Regular papers》2008,55(1):445-461
13.
Enhancement of islanding-detection of distributed generation systems via wavelet transform-based approaches 总被引:1,自引:1,他引:0
Cheng-Tao Hsieh Jeu-Min Lin Shyh-Jier Huang 《International Journal of Electrical Power & Energy Systems》2008,30(10):575-580
In this paper, a wavelet transform-based approach is proposed to detect the occurrence of islanding events in distributed generation systems. Thanks to time–frequency localization capabilities exhibited by wavelet transform, the approach embedded with this transform technique has grasped the appearance of the islanding event in a highly effective manner. Moreover, for those regions which are in need of a better visualization, the proposed approach would serve as an efficient aid such that the mains power disconnection can be better distinguished. To validate the feasibility of this approach, the method has been validated through several scenarios. Test results supported the effectiveness of the method for the application considered. 相似文献
14.
15.
The width of the transition layer between the crystalline and amorphous zones in nylon 1010 was determined by SAXS with point collimation and long-slit collimation, respectively. The width of the transition layer, E, was found to be 1.7 nm. The results show that the width of the transition layer is independent of crystallinity. 相似文献
16.
We have studied lamp configuration design for rapid thermal processing (RTP) systems. We considered a configuration consisting of four concentric circular lamp zones, three of them above the wafer and one circumventing the wafer. We propose a method to determine the geometric parameters, the width, height and radius, of the lamp zones so that the configuration designed has the capacity to achieve a uniform temperature on the wafer. The method is based on a necessary and sufficient condition for uniform temperature tracking and analytic expressions of the view factors. A design example is given in which a least square open-loop control law yields good temperature uniformity 相似文献
17.
A technique for SiO2 formation by liquid-phase deposition (LPD) at nearly room temperature for low-temperature processed (LTP) polysilicon thin-film transistor (poly-Si TFT) was developed. LPD SiO2 film with a lower P-etch rate shows a dense structure. LPD SiO2 also exhibits good electrical characteristics. LTP poly-Si thin-film transistors (TFTs) with LPD SiO 2 as the gate insulator have been fabricated and investigated. Their characteristics indicate performance adequate for their use as pixel transistors in liquid crystal displays (LCDs) 相似文献
18.
Shyh-Jier Huang Jeu-Min Lin 《Power Systems, IEEE Transactions on》2002,17(4):1022-1029
In this paper, a gap-statistic-algorithm (GSA)-based data-mining technique is applied to enhance the data debugging in power system operations. In the proposed approach, the GSA technique is embedded into a neural network frame in anticipation of improving the detection capability of bad data. Thanks to the clustering capability exhibited by GSA in which the number of clusters can be optimally determined, the proposed approach becomes highly effective to localize the group of abnormal data. This proposed approach has been tested through the data collected from different scenarios made on an IEEE 30-bus system and 118-bus systems. Test results reveal the feasibility of the method for the data diagnosis applications. 相似文献
19.
Tzu-Ming Liu Yin-Chieh Huang Gia-Wei Chern Kung-Hsuan Lin Yu-Chueh Hung Chih-Jie Lee Chi-Kuang Sun 《Quantum Electronics, IEEE Journal of》2002,38(11):1529-1535
We present a method to obtain complete information of femtosecond pulses. By measuring triple-optical autocorrelation directly with third-harmonic generation, without spectral information, a temporal pulse shape can be obtained by analytical calculation without direction-of-time ambiguity. Combining the resulting optical pulse shape with its corresponding optical spectrum, the exact phase and color variations in time can all be recovered with a Gerchberg-Saxton algorithm through an iterative calculation with an O(n) complexity. 相似文献
20.
Chai-Chin Lin Chih-Ming Chen Jenn-Hwan Tarng Hsueh-Ming Hang Hsiao-Cheng Yu 《Broadcasting, IEEE Transactions on》2002,48(1):38-43
Field tests of the transmission performance of the ATSC DTV system have been conducted in Taiwan. The test results as well as comparisons against the NTSC system performance are reported and analyzed. From the measured results the reception characteristics of the DTV can be deduced and can provide guidelines for television stations to design the transmission system, schedule equipment deployment, plan service coverage areas, and improve the reception quality of the digital signal 相似文献