全文获取类型
收费全文 | 2203篇 |
免费 | 17篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 54篇 |
综合类 | 2篇 |
化学工业 | 216篇 |
金属工艺 | 25篇 |
机械仪表 | 17篇 |
建筑科学 | 7篇 |
能源动力 | 36篇 |
轻工业 | 89篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 191篇 |
一般工业技术 | 139篇 |
冶金工业 | 1322篇 |
原子能技术 | 17篇 |
自动化技术 | 104篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 18篇 |
2020年 | 8篇 |
2019年 | 10篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 19篇 |
2015年 | 17篇 |
2014年 | 20篇 |
2013年 | 53篇 |
2012年 | 35篇 |
2011年 | 49篇 |
2010年 | 30篇 |
2009年 | 44篇 |
2008年 | 34篇 |
2007年 | 40篇 |
2006年 | 42篇 |
2005年 | 30篇 |
2004年 | 39篇 |
2003年 | 31篇 |
2002年 | 24篇 |
2001年 | 27篇 |
2000年 | 31篇 |
1999年 | 54篇 |
1998年 | 452篇 |
1997年 | 219篇 |
1996年 | 165篇 |
1995年 | 104篇 |
1994年 | 80篇 |
1993年 | 99篇 |
1992年 | 20篇 |
1991年 | 31篇 |
1990年 | 35篇 |
1989年 | 36篇 |
1988年 | 23篇 |
1987年 | 26篇 |
1986年 | 24篇 |
1985年 | 19篇 |
1984年 | 10篇 |
1983年 | 8篇 |
1982年 | 11篇 |
1981年 | 13篇 |
1980年 | 14篇 |
1978年 | 3篇 |
1977年 | 38篇 |
1976年 | 90篇 |
1975年 | 7篇 |
1955年 | 3篇 |
1932年 | 2篇 |
排序方式: 共有2222条查询结果,搜索用时 0 毫秒
1.
Mita T. Hirata M. Murata K. Zhang H. 《Industrial Electronics, IEEE Transactions on》1998,45(3):488-495
In the motion control field, a disturbance observer-based disturbance canceling control is often used as a robust control methodology. However, this method is nothing more than an alternative design of an integral controller, and the robust stability issue cannot be directly accounted for. In this paper, an extended H∞ control scheme is proposed as a new robust motion control method which achieves the disturbance cancellation ability and guarantees robust stability automatically 相似文献
2.
Discovery of Web communities, groups of Web pages sharing common interests, is important for assisting users' information retrieval from the Web. This paper describes a method for visualizing Web communities and their internal structures. visualization of Web communities in the form of graphs enables users to access related pages easily, and it often reflects the characteristics of the Web communities. Since related Web pages are often co-referred from the same Web page, the number of co-occurrences of references in a search engine is used for measuring the relation among pages. Two URLs are given to a search engine as keywords, and the value of the number of pages searched from both URLs divided by the number of pages searched from either URL, which is called the Jaccard coefficient, is calculated as the criteria for evaluating the relation between the two URLs. The value is used for determining the length of an edge in a graph so that vertices of related pages will be located close to each other. Our visualization system based on the method succeeds in clarifying various genres of Web communities, although the system does not interpret the contents of the pages. The method of calculating the Jaccard coefficient is easily processed by computer systems, and it is suitable for visualization using the data acquired from a search engine. 相似文献
3.
M Murata 《Canadian Metallurgical Quarterly》1993,65(11):1434-1438
4.
B Lubec S Fang-Kircher T Lubec HJ Blom GH Boers 《Canadian Metallurgical Quarterly》1996,1315(3):159-162
Fractionation of the venom of the spider Phoneutria nigriventer revealed that it was a mixture of several neurotoxic peptides. The peptides so far characterized either inhibited or induced neurotransmitter release. These effects were mediated by Ca2+ channels or increasing Na+ permeability through voltage sensitive Na(+)-channels, respectively. The pooled toxic components (fraction P4) showed stimulatory effects on acetylcholine release from brain cortical slices. In addition, a component of the observed effects resembling that of alpha-latrotoxin was identified, which was characterized by the ability to provoke release of acetylcholine (ACh) at low temperature and in a manner independent of extracellular Ca2+ and of voltage sensitive Na(+)-channels. 相似文献
5.
6.
7.
8.
The right eye of a 9-year-old white boy with Best's vitelliform macular dystrophy had an intact egg-yolk lesion and a retinal pigment epithelial defect superiorly, suggesting an early pseudohypopyon stage. The disruptive phase of the left eye showed subretinal hemorrhages, a "signet ring," and a subretinal neovascular membrane. 相似文献
9.
10.