全文获取类型
收费全文 | 2633篇 |
免费 | 562篇 |
国内免费 | 603篇 |
专业分类
电工技术 | 457篇 |
综合类 | 450篇 |
化学工业 | 80篇 |
金属工艺 | 20篇 |
机械仪表 | 156篇 |
建筑科学 | 62篇 |
矿业工程 | 21篇 |
能源动力 | 48篇 |
轻工业 | 29篇 |
水利工程 | 8篇 |
石油天然气 | 9篇 |
武器工业 | 75篇 |
无线电 | 339篇 |
一般工业技术 | 231篇 |
冶金工业 | 24篇 |
原子能技术 | 7篇 |
自动化技术 | 1782篇 |
出版年
2024年 | 20篇 |
2023年 | 67篇 |
2022年 | 85篇 |
2021年 | 96篇 |
2020年 | 120篇 |
2019年 | 113篇 |
2018年 | 92篇 |
2017年 | 119篇 |
2016年 | 134篇 |
2015年 | 149篇 |
2014年 | 196篇 |
2013年 | 211篇 |
2012年 | 211篇 |
2011年 | 219篇 |
2010年 | 196篇 |
2009年 | 183篇 |
2008年 | 179篇 |
2007年 | 186篇 |
2006年 | 170篇 |
2005年 | 145篇 |
2004年 | 139篇 |
2003年 | 98篇 |
2002年 | 89篇 |
2001年 | 87篇 |
2000年 | 67篇 |
1999年 | 51篇 |
1998年 | 45篇 |
1997年 | 42篇 |
1996年 | 43篇 |
1995年 | 40篇 |
1994年 | 38篇 |
1993年 | 33篇 |
1992年 | 30篇 |
1991年 | 30篇 |
1990年 | 31篇 |
1989年 | 15篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1984年 | 8篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1951年 | 1篇 |
排序方式: 共有3798条查询结果,搜索用时 15 毫秒
1.
2.
The general mixed μ problem has been shown to be NP hard, so that the exact solution of the general problem is computationally intractable, except for small problems. In this paper we consider not the general problem, but a particular special case of this problem, the rank one mixed μ problem. We show that for this case the mixed μ problem is equivalent to its upper bound (which is convex), and it can in fact be computed easily (and exactly). This special case is shown to be equivalent to the so-called ‘affine parameter variation’ problem (for a polynomial with perturbed coefficients) which has been examined in detail in the literature, and for which several celebrated ‘Kharitonov-type’ results have been proven. 相似文献
3.
神经网络离散变结构控制的算法及其应用 总被引:3,自引:0,他引:3
本文首次将自适应线性神经元(Adaline)用于离散变结构控制。以滑模面S(k)=0作为Adaline元的希望输出,作为Adaline元的实际输出,通过LMS算法在线调整权值可保证滑态可达条件的满足。应用所提出的控制策略对泵控马达速度伺服系统进行控制,仿真表明控制效果是令人满意的。 相似文献
4.
Haitao Zhang Zonghai Chen Yongji Wang Ming Li Ting Qin 《International Journal of Adaptive Control and Signal Processing》2006,20(2):53-76
Laguerre Functional Model has many advantages such as good approximation capability for the variances of system time‐delay, order and other structural parameters, low computational complexity, and the facility of online parameter identification, etc., so this model is suitable for complex industrial process control. A series of successful applications have been gained in linear and non‐linear predictive control fields by the control algorithm based on Laguerre Functional Model, however, former researchers have not systemically brought forward the theoretical analyses of the stability, robustness, and steady‐state performance of this algorithm, which are the keys to guarantee the feasibility of the control algorithm fundamentally. Aimed at this problem, we introduce the principles of the Incremental Mode Linear Laguerre Predictive Control (IMLLPC) algorithm, and then systemically propose the theoretical analyses and proofs of the stability and robustness of the algorithm, in addition, we also put forward the steady‐state performance analysis. At last, the control performances of this algorithm on two different physical industrial plants are presented in detail, and a number of experimental results validate the feasibility and superiority of IMLLPC algorithm. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
5.
A robustness analysis and synthesis for incomplete nonlinear decoupling for a class of nonlinear systems is discussed. Rigid and elastic-joint robot models belong to this class. For the elastic case, a transformation facilitates the robustness analysis under a weak assumption. Charts with H
1- and H
- norms of closed-loop disturbance transfer functions of the nonlinear-decoupled system are presented for a robust pole assignment. 相似文献
6.
This paper presents the robust velocity estimation of an omnidirectional mobile robot using a regular polygonal array of optical mice that are installed at the bottom of a mobile robot. First, the velocity kinematics from a mobile robot to an array of optical mice is derived, from which the least squares estimation of the mobile robot velocity is obtained as the simple average of the optical mouse velocity readings. Second, it is shown that a redundant number of optical mice contributes to the robustness of the least squares mobile robot velocity estimation against both measurement noises and partial malfunction of optical mice. Third, the sensitivity analysis of the least squares mobile robot velocity estimation to imprecise installation of optical mice is made, from which a practical method of optical mouse position calibration is devised. Finally, some experimental results using commercial optical mice are given to demonstrate the validity and performance of the proposed mobile robot velocity estimation. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
7.
Xiuming Huang 《Machine Translation》1988,3(2):101-120
This paper concerns the resolution of lexical ambiguity in a machine translation environment. We describe the integration of principles of selection restrictions. Preference Semantics, and intelligent relaxation of constraints in handling lexical ambiguity. The approach differs from many previous MT systems in that it is more powerful than brute force systems, while more realistic than systems that assume a large degree of coded encyclopedia information for full understanding. 相似文献
8.
针对空间机械臂在地面装调与空间应用时,由于重力环境变化导致机械臂模型发生变化的问题,提出了一种自抗扰控制算法,用于完成空间机械臂轨迹跟踪控制的任务.该算法通过将系统模型及未知外扰作为系统的总和扰动,并利用扩张状态观测器对该扰动进行观测且给予补偿,从而提高了系统抗扰的性能.当机械臂模型随重力环境变化而发生变化时,使用同一个自抗扰控制器对其末端轨迹进行控制,均能取得较好的控制效果.通过对系统的稳定性进行分析,证明了所设计控制器的有效性.将仿真结果与PD控制及自适应鲁棒控制做比较,结果表明该控制算法不仅能适应机械臂模型的变化而且还能有效抵抗系统的扰动,从而使系统具有较强的鲁棒性. 相似文献
9.
针对复杂图像背景及光照导致的肤色检测率不高的问题,提出一种基于分裂式K均值聚类的椭圆模型肤色检测方法。该方法对图像进行光线补偿处理,采用Gray World方法对图像进行颜色均衡,选择建立检测效率较高的椭圆肤色模型进行肤色检测,并在检测出的肤色区域上采用分裂式K均值聚类(FKM)进行二次的肤色判决,进一步准确检测出肤色区域。实验表明,所提出的检测算法能准确高效地检测出肤色区域,具有较高地准确率和较强的鲁棒性。 相似文献
10.
研究应对不确定因素的鲁棒性项目调度, 针对其所用时间缓冲区技术中的两种重要方法——集中缓冲和STC (starting time criticality) 分散缓冲, 采用仿真模拟实验, 以项目管理库中的帕特森例1 为对象, 进行详细的比较研究. 研究结果表明, 分散缓冲法具有更好的解鲁棒性; 当活动时间的不确定性程度较大时, 集中缓冲法的质量鲁棒性较好; 当项目工期较紧时, 分散缓冲法具有更好的鲁棒性. 这些研究结论为管理者在特定的项目环境下选择合适的缓冲方法提供了决策依据. 相似文献