全文获取类型
收费全文 | 19968篇 |
免费 | 2335篇 |
国内免费 | 11篇 |
专业分类
电工技术 | 1479篇 |
综合类 | 869篇 |
化学工业 | 9442篇 |
金属工艺 | 336篇 |
机械仪表 | 430篇 |
建筑科学 | 737篇 |
矿业工程 | 181篇 |
能源动力 | 146篇 |
轻工业 | 1781篇 |
水利工程 | 152篇 |
石油天然气 | 73篇 |
武器工业 | 1篇 |
无线电 | 486篇 |
一般工业技术 | 3448篇 |
冶金工业 | 546篇 |
原子能技术 | 51篇 |
自动化技术 | 2156篇 |
出版年
2023年 | 680篇 |
2022年 | 354篇 |
2021年 | 747篇 |
2020年 | 735篇 |
2019年 | 630篇 |
2018年 | 605篇 |
2017年 | 415篇 |
2016年 | 665篇 |
2015年 | 848篇 |
2014年 | 879篇 |
2013年 | 1541篇 |
2012年 | 603篇 |
2011年 | 485篇 |
2010年 | 873篇 |
2009年 | 1025篇 |
2008年 | 467篇 |
2007年 | 419篇 |
2006年 | 319篇 |
2005年 | 339篇 |
2004年 | 364篇 |
2003年 | 322篇 |
2002年 | 271篇 |
2001年 | 192篇 |
1998年 | 347篇 |
1997年 | 253篇 |
1996年 | 268篇 |
1995年 | 243篇 |
1994年 | 207篇 |
1993年 | 280篇 |
1992年 | 191篇 |
1991年 | 165篇 |
1990年 | 178篇 |
1989年 | 211篇 |
1988年 | 168篇 |
1987年 | 198篇 |
1986年 | 217篇 |
1985年 | 188篇 |
1984年 | 197篇 |
1983年 | 201篇 |
1982年 | 180篇 |
1981年 | 233篇 |
1980年 | 186篇 |
1979年 | 185篇 |
1977年 | 171篇 |
1976年 | 183篇 |
1975年 | 225篇 |
1974年 | 204篇 |
1973年 | 386篇 |
1972年 | 236篇 |
1968年 | 159篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Yurak Son Takuya Kamano Takashi Yasuno Takayuki Suzuki Hironobu Harada 《Electrical Engineering in Japan》2006,155(1):35-43
This paper describes the generation of adaptive gait patterns using new Central Pattern Generators (CPGs) including motor dynamic models for a quadruped robot under various environments. The CPGs act as the flexible oscillators of the joints and adjust joint angles to required values. The CPGs are interconnected with each other and sets of their coupling parameters are adjusted by a genetic algorithm so that the quadruped robot can realize stable and adequate gait patterns. Generation of gait patterns results in the formation of the CPG networks suitable for the formation of not only a straight walking pattern but also of rotating gait patterns. Experimental results demonstrate that the proposed CPG networks are effective for the automatic adjustment of the adaptive gait patterns for the tested quadruped robot under various environments. Furthermore, the target tracking control based on image processing is achieved by combining the general gait patterns. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 35–43, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20225 相似文献
62.
63.
Summary Plastic yielding of anisotropic metals can be either described by a macroscopic constitutive relation or assessed by means of a model which correlates single and polycrystal behaviors. The mathematical identification of the plastic work rate derived from the two approaches, for all strain rate tensors, leads to a fit of the polycrystal yield surface by an analytical function. When a quadratic from is assumed, the macroscopic anisotropy parameters become explicit functions of the texture coefficients. This identification method is applied to calculate yield surfaces andR-values of rolled and annealed steel sheets: theR-values and in general the flow rule, are more significantly modified by the fitting than the yield surface. Thus, it is worth extending the method to more general constitutive relations which may be given by the form of their work function: alternative forms of the work function for plastic materials are explored, especially in the bearing of convexity and homogeneity where quadratic forms have a distinct advantage. Finally, it is shown that the identification of the work function allows to express the phenomenological coefficients as analytical functions of the texture parameters for many forms of the work function; in the other cases, these coefficients may be obtained by linear or non-linear regression. 相似文献
64.
65.
66.
67.
68.
Dr. K. Whybrew J. K. Raine G. R. Dunlop H. Overbye 《The International Journal of Advanced Manufacturing Technology》1993,8(2):111-113
An articulated geometry which overcomes the problem of loss of traction in differentially steered skid tractor automatic guided vehicles is described. 相似文献
69.
70.