全文获取类型
收费全文 | 10714篇 |
免费 | 142篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 153篇 |
化学工业 | 633篇 |
金属工艺 | 296篇 |
机械仪表 | 62篇 |
建筑科学 | 78篇 |
矿业工程 | 1篇 |
能源动力 | 87篇 |
轻工业 | 383篇 |
水利工程 | 7篇 |
石油天然气 | 8篇 |
无线电 | 367篇 |
一般工业技术 | 304篇 |
冶金工业 | 315篇 |
原子能技术 | 89篇 |
自动化技术 | 8078篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 30篇 |
2021年 | 61篇 |
2020年 | 38篇 |
2019年 | 43篇 |
2018年 | 54篇 |
2017年 | 54篇 |
2016年 | 48篇 |
2015年 | 62篇 |
2014年 | 271篇 |
2013年 | 272篇 |
2012年 | 846篇 |
2011年 | 2385篇 |
2010年 | 1182篇 |
2009年 | 1035篇 |
2008年 | 748篇 |
2007年 | 652篇 |
2006年 | 497篇 |
2005年 | 608篇 |
2004年 | 561篇 |
2003年 | 620篇 |
2002年 | 316篇 |
2001年 | 37篇 |
2000年 | 29篇 |
1999年 | 27篇 |
1998年 | 105篇 |
1997年 | 66篇 |
1996年 | 46篇 |
1995年 | 27篇 |
1994年 | 24篇 |
1993年 | 27篇 |
1992年 | 3篇 |
1991年 | 10篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 10篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1977年 | 3篇 |
1976年 | 10篇 |
1975年 | 3篇 |
1968年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
991.
Alessandro Chiuso Author Vitae Author Vitae 《Automatica》2004,40(4):575-589
There is experimental evidence that the performance of standard subspace algorithms from the literature (e.g. the N4SID method) may be surprisingly poor in certain experimental conditions. This happens typically when the past signals (past inputs and outputs) and future input spaces are nearly parallel. In this paper we argue that the poor behavior may be attributed to a form of ill-conditioning of the underlying multiple regression problem, which may occur for nearly parallel regressors. An elementary error analysis of the subspace identification problem, shows that there are two main possible causes of ill-conditioning. The first has to do with near collinearity of the state and future input subspaces. The second has to do with the dynamical structure of the input signal and may roughly be attributed to “lack of excitation”. Stochastic realization theory constitutes a natural setting for analyzing subspace identification methods. In this setting, we undertake a comparative study of three widely used subspace methods (N4SID, Robust N4SID and PO-MOESP). The last two methods are proven to be essentially equivalent and the relative accuracy, regarding the estimation of the (A,C) parameters, is shown to be the same. 相似文献
992.
A practical implementation of stochastic programming: an application to the evaluation of option contracts in supply chains 总被引:1,自引:0,他引:1
Ch. van Delft Author Vitae 《Automatica》2004,40(5):743-756
Stochastic programming is a powerful analytical method in order to solve sequential decision-making problems under uncertainty. We describe an approach to build such stochastic linear programming models. We show that algebraic modeling languages make it possible for non-specialist users to formulate complex problems and have solved them by powerful commercial solvers. We illustrate our point in the case of option contracts in supply chain management and propose a numerical analysis of performance. We propose easy-to-implement discretization procedures of the stochastic process in order to limit the size of the event tree in a multi-period environment. 相似文献
993.
Lihua Xie Author Vitae Lilei Lu Author Vitae Author Vitae Huanshui Zhang Author Vitae 《Automatica》2004,40(5):873-880
This paper is concerned with the robust H2 and H∞ filtering problems for linear discrete-time systems with polytopic parameter uncertainty. We aim to derive a less-conservative design than existing linear matrix inequality (LMI) based sufficient conditions. It is shown that a more efficient evaluation of robust H2 or H∞ performance can be obtained by a matrix inequality condition which contains additional free parameters as compared to existing characterizations. When applying this new matrix inequality condition to the robust filter design, these parameters provide extra degrees of freedom in optimizing the guaranteed H2 or H∞ performance and lead to a less-conservative design. 相似文献
994.
An analysis of the parametrization by data driven local coordinates for multivariable linear systems
Thomas Ribarits Author Vitae Manfred Deistler Author Vitae Tomas McKelvey Author Vitae 《Automatica》2004,40(5):789-803
In this paper, we study a novel parametrization for state-space systems, namely data driven local coordinates (DDLC) which have recently been introduced and applied. Even though DDLC has meanwhile become the default parametrization used in the system identification toolbox of the software package MATLAB, an analysis of properties of DDLC, which are relevant to identification, has not been performed up to now. In this paper, we provide insights into the geometry and topology of the DDLC construction and show a number of results which are important for actual identification such as maximum likelihood-type estimation. 相似文献
995.
In this paper, we first study strong positive-realness of sampled-data systems and introduce a measure called positive-realness gap index. We show that this index can be computed efficiently with a bisection method, and provide state space formulas for its computation. The importance of this index lies in that it is useful for robust stability analysis of sampled-data systems. An iterative procedure for computing an exact robust stability margin is given and illustrated through a numerical example. 相似文献
996.
Ellipsoidal outer-bounding of the set of all feasible state vectors under model uncertainty is a natural extension of state estimation for deterministic models with unknown-but-bounded state perturbations and measurement noise. The technique described in this paper applies to linear discrete-time dynamic systems; it can also be applied to weakly non-linear systems if non-linearity is replaced by uncertainty. Many difficulties arise because of the non-convexity of feasible sets. Combined quadratic constraints on model uncertainty and additive disturbances are considered in order to simplify the analysis. Analytical optimal or suboptimal solutions of the basic problems involved in parameter or state estimation are presented, which are counterparts in this context of uncertain models to classical approximations of the sum and intersection of ellipsoids. The results obtained for combined quadratic constraints are extended to other types of model uncertainty. 相似文献
997.
Decentralized overlapping feedback laws are designed for a formation of unmanned aerial vehicles. The dynamic model of the formation with an information structure constraint in which each vehicle, except the leader, only detects the vehicle directly in front of it, is treated as an interconnected system with overlapping subsystems. Using the mathematical framework of the inclusion principle, the interconnected system is expanded into a higher dimensional space in which the subsystems appear to be disjoint. Then, at each subsystem, a static state feedback controller is designed to robustly stabilize the perturbed nominal dynamics of the subsystem. The design procedure is based on the application of convex optimization tools involving linear matrix inequalities. As a final step, the decentralized controllers are contracted back to the original interconnected system for implementation. 相似文献
998.
Nonlinear system fault diagnosis based on adaptive estimation 总被引:2,自引:0,他引:2
Aiping Xu Author Vitae 《Automatica》2004,40(7):1181-1193
An approach to fault diagnosis for a class of nonlinear systems is proposed in this paper. It is based on a new adaptive estimation algorithm for recursive estimation of the parameters related to faults. This algorithm is designed in a constructive manner through a nontrivial combination of a high gain observer and a recently developed linear adaptive observer, without resort to any linearization. Its global exponential convergence is ensured by an easy-to-check persistent excitation condition. A numerical example is presented for illustration. 相似文献
999.
We consider a control problem for a single bioreaction occurring in a continuous and well-mixed bioreactor, assuming that the bioreaction's kinetics is not represented by a validated model. We develop a nonlinear controller and prove the global asymptotic stability of the closed-loop system towards the equilibrium corresponding to the set point. Since this control law needs the knowledge of some parameters, we derive an adaptive version of the nonlinear controller and prove again the global asymptotic stability of the closed-loop system. Finally, we show the relevance of our approach on a real-life wastewater treatment plant. 相似文献
1000.
In this work, an iterative learning control scheme is designed for a class of nonlinear uncertain systems with input saturation. The analysis of convergence in the iteration domain is based on composite energy function, which consists of both input and state information along the time and iteration axes. Through rigorous analysis, the learning convergence in the iteration domain can be guaranteed under the input saturation, provided the desired trajectory is realizable within the saturation bound. 相似文献