全文获取类型
收费全文 | 7365篇 |
免费 | 587篇 |
国内免费 | 506篇 |
专业分类
电工技术 | 579篇 |
综合类 | 235篇 |
化学工业 | 160篇 |
金属工艺 | 252篇 |
机械仪表 | 701篇 |
建筑科学 | 174篇 |
矿业工程 | 17篇 |
能源动力 | 133篇 |
轻工业 | 16篇 |
水利工程 | 24篇 |
石油天然气 | 10篇 |
武器工业 | 74篇 |
无线电 | 1289篇 |
一般工业技术 | 334篇 |
冶金工业 | 29篇 |
原子能技术 | 46篇 |
自动化技术 | 4385篇 |
出版年
2024年 | 20篇 |
2023年 | 109篇 |
2022年 | 163篇 |
2021年 | 185篇 |
2020年 | 181篇 |
2019年 | 221篇 |
2018年 | 190篇 |
2017年 | 298篇 |
2016年 | 295篇 |
2015年 | 290篇 |
2014年 | 456篇 |
2013年 | 468篇 |
2012年 | 384篇 |
2011年 | 504篇 |
2010年 | 381篇 |
2009年 | 479篇 |
2008年 | 481篇 |
2007年 | 450篇 |
2006年 | 414篇 |
2005年 | 360篇 |
2004年 | 300篇 |
2003年 | 292篇 |
2002年 | 220篇 |
2001年 | 151篇 |
2000年 | 146篇 |
1999年 | 122篇 |
1998年 | 125篇 |
1997年 | 95篇 |
1996年 | 86篇 |
1995年 | 68篇 |
1994年 | 68篇 |
1993年 | 85篇 |
1992年 | 63篇 |
1991年 | 26篇 |
1990年 | 34篇 |
1989年 | 38篇 |
1988年 | 40篇 |
1987年 | 24篇 |
1986年 | 26篇 |
1985年 | 17篇 |
1984年 | 29篇 |
1983年 | 12篇 |
1982年 | 16篇 |
1981年 | 13篇 |
1980年 | 13篇 |
1979年 | 11篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1976年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有8458条查询结果,搜索用时 31 毫秒
51.
This paper shows how the theory of nonlinear adaptive observers can be effectively used in the design of internal models for nonlinear output regulation. The theory substantially enhances the existing results in the context of adaptive output regulation, by allowing for not necessarily stable zero dynamics of the controlled plant and by weakening the standard assumption of having the steady-state control input generated by a linear system. 相似文献
52.
High accuracy path tracking for vehicles in presence of sliding: Application to farm vehicle automatic guidance for agricultural tasks 总被引:1,自引:0,他引:1
Roland Lenain Benoit Thuilot Christophe Cariou Philippe Martinet 《Autonomous Robots》2006,21(1):79-97
When designing an accurate automated guidance system for vehicles, a major problem is sliding and pseudo-sliding effects. This is especially the case in agricultural applications, where five-centimetre accuracy with respect to the desired trajectory is required, although the vehicles are moving on slippery ground. It has been established that RTK GPS was a very suitable sensor to achieve automated guidance with such high precision: several control laws have been designed for vehicles equipped with this sensor, and provide the expected guidance accuracy as long as the vehicles do not slide. In previous work, further control developments have been proposed to take sliding into account: guidance accuracy in slippery environments has been shown to be preserved, except transiently at the beginning/end of curves. In this paper, the design of this control law is first recalled and discussed. A Model Predictive Control method is then applied in order to preserve accuracy of guidance even during these curvature transitions. Finally, the overall control scheme is implemented, and improvements with respect to previous guidance laws are demonstrated through full-scale experiments. 相似文献
53.
In this paper, we employ a nonlinear adaptive mechanism to globally stabilize nth-order reactions. 相似文献
54.
Minimal inhibitory concentration (MIC), suspension and biofilm tests were used in evaluating the disinfecting efficacy of eight commercially available disinfectants and four chlorinated alkaline cleaners against 10 strains of Listeria monocytogenes at refrigerated temperatures. The adaptive response and cross-adaptation of L. monocytogenes to the disinfectants and chlorinated alkaline cleaners were investigated. The bactericidal components in the agents used were chlorine, quaternary ammonium compound (QAC), peracetic acid, ethanol and isopropanol. With some exceptions the disinfectants were efficient against the L. monocytogenes strains. One alkaline hypochlorite containing disinfectant was not efficient in the suspension and MIC tests at the lowest concentration recommended by the manufacturer. The chlorinated alkaline cleaners were effective against L. monocytogenes. A QAC-based disinfectant was found to be the least-effective agent on both glass bead-blasted polyethylene and stainless-steel surfaces. Adaptive and cross-adaptive responses of L. monocytogenes strains were observed towards the QAC-based agent, but over 2-fold increases to other agents were not observed. These results suggest that the adaptive responses of L. monocytogenes to disinfectants or chlorinated alkaline cleaners are of a minor concern. 相似文献
55.
为了降低转子电阻变化对异步电动机矢量控制系统性能的影响,本文把自适应比例因子模糊控制器应用到了矢量控制系统中。介绍了自适应比例因子模糊控制方法的綦本原理,给出了使用自适应比例因子模糊控制器的异步电动机矢量控制系统的结构框图,对主模糊控制器和辅助模糊控制器进行了设计。仿真实验结果表明,采用这种控制方法的调速系统不仅具有优良的动态性能,而且对转子电阻变化具有很强的鲁棒性。 相似文献
56.
57.
This paper is concerned with the achievable performance of adaptive control algorithms. We show that when the only uncertainty is in the form of fixed parameter errors, then there exists an adaptive feedback law whose performance can be made arbitrarily close to that achievable when the system is a priori known. The result is not intended as a practical strategy. Instead, we use it to make the, perhaps obvious, point that meaningful results on performance of adaptive control algorithms must account for non-ideal factors including, at a minimum, noise, parameter time variations and unstructured uncertainty. 相似文献
58.
机载红外搜索跟踪系统被动定位滤波算法研究 总被引:1,自引:1,他引:0
首先用扩展卡尔曼滤波算法构建了机载红外搜索跟踪系统被动定位滤波模型.然后针对该滤波算法要求先验的噪声统计及存在系统观测模型线性化误差影响滤波精度的特点.利用虚拟噪声技术,提出了适合于红外搜索跟踪系统被动定位的自适应扩展卡尔曼滤波算法。该算法实时地估计了虚拟噪声的统计特性,减小了线性化误差,提高了非线性滤波的精度。仿真结果表明,在完全相同的初始条件下,自适应扩展卡尔曼滤波对目标距离和速度的估计结果明显优于扩展卡尔曼滤波,此算法具有很高的工程应用价值。 相似文献
59.
60.
根据锆钛酸铅压电陶瓷的逆压电效应。设计了以8031单片机为核心的压电陶瓷堆微位移器提高了PZT的线性,从而满足了在天文自适应系统中所要求的精确微位的应用。 相似文献