全文获取类型
收费全文 | 1420篇 |
免费 | 200篇 |
国内免费 | 75篇 |
专业分类
化学 | 716篇 |
晶体学 | 9篇 |
力学 | 136篇 |
综合类 | 8篇 |
数学 | 403篇 |
物理学 | 423篇 |
出版年
2024年 | 1篇 |
2023年 | 17篇 |
2022年 | 32篇 |
2021年 | 30篇 |
2020年 | 50篇 |
2019年 | 43篇 |
2018年 | 32篇 |
2017年 | 46篇 |
2016年 | 59篇 |
2015年 | 38篇 |
2014年 | 80篇 |
2013年 | 121篇 |
2012年 | 72篇 |
2011年 | 79篇 |
2010年 | 58篇 |
2009年 | 73篇 |
2008年 | 83篇 |
2007年 | 102篇 |
2006年 | 88篇 |
2005年 | 69篇 |
2004年 | 78篇 |
2003年 | 71篇 |
2002年 | 40篇 |
2001年 | 45篇 |
2000年 | 39篇 |
1999年 | 43篇 |
1998年 | 40篇 |
1997年 | 26篇 |
1996年 | 20篇 |
1995年 | 24篇 |
1994年 | 26篇 |
1993年 | 9篇 |
1992年 | 11篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
排序方式: 共有1695条查询结果,搜索用时 15 毫秒
51.
This paper is concerned with the robust stabilization problem for a class of linear uncertain stochastic systems with Markovian switching. The uncertain stochastic system with Markovian switching under consideration involves parameter uncertainties both in the system matrices and in the mode transition rates matrix. New criteria for testing the robust stability of such systems are established in terms of bi-linear matrix inequalities (BLMIs), and sufficient conditions are proposed for the design of robust state-feedback controllers. A numerical example is given to illustrate the effectiveness of our results. 相似文献
52.
基于输出反馈的一类大型互联非线性系统的鲁棒全局指数稳定 总被引:3,自引:1,他引:3
研究基于输出反馈的一类新的大型互联非线性不确定系统的鲁棒全局指数稳定问题,通过构造每个子系统收敛的状态观测器,并对观测器的状态作线性变换,得到鲁棒分散输出反馈控制器.当该反馈控制律作用于该系统时,闭环系统是全局指数稳定的. 相似文献
53.
《Mathematical Methods in the Applied Sciences》2018,41(10):3684-3695
The paper formulates effective and nonimprovable stability conditions for a linear difference system involving 2 integer delays. The used technique combines algorithm of the discrete D‐decomposition method with some procedures of the polynomial theory. Contrary to the related existing results, the derived conditions are fully explicit with respect to both delays, which enables their simple applicability in various scientific and engineering areas. As an illustration, we show their importance in delayed feedback controls of discrete dynamical systems, with a particular emphasis put on stabilization of unstable steady states of the discrete logistic map. 相似文献
54.
This paper is concerned with the co-design of event-triggered sampling, dynamic input quantization and constrained switching for a switched linear system. The mismatch between the plant and its corresponding controller is considered. This behavior is raised by switching within the event-triggered sampling interval. Accordingly, novel update laws of dynamic quantization parameter are designed separately for matched sampling intervals (without switching) and mismatched sampling intervals (with a switch). We technically transform the total variation (increment or decrement) of Lyapunov functions in one sampling interval into the discrete-time update of quantization parameter. Based on this transformation, a hybrid quantized control policy is developed. This policy, in conjunction with the average dwell-time switching law and the constructed event-triggered condition, can ensure the exponential stabilization of the switched system with finite-level quantized input. Besides, the event-triggered scheme is proved to be Zeno-free. The effectiveness of the developed method is verified by a simulation example. 相似文献
55.
P. K. C. Wang 《Journal of Optimization Theory and Applications》1990,65(2):331-362
This paper considers the problem of the stabilization and control of distributed systems with time-dependent spatial domains. The evolution of the spatial domains with time is described by a finite-dimensional system of ordinary differential equations, while the distributed systems are described by first-order or second-order linear evolution equations defined on appropriate Hilbert spaces. First, results pertaining to the existence and uniqueness of solutions of the system equations are presented. Then, various optimal control and stabilization problems are considered. The paper concludes with some examples which illustrate the application of the main results.This work was supported by the Air Force Office of Scientific Research, Grant No. AFOSR 86-0132, by the National Science Foundation, Grant No. 87-18473, and by the Jet Propulsion Laboratory, Pasadena, California. 相似文献
56.
In this paper, we study the exact controllability and boundary stabilization of the torsional vibrations of a flexible space structure (such as a solar cell array) modeled by a rectangular panel, incorporating the material damping of the structure. The panel is hoisted at one end by a rigid hub and the other end is totally free. For the attachment of this hub on one side of the panel, the hub dynamics leads to a nonstandard boundary condition. To incorporate internal damping of the material, we assume Voigt-type viscoelasticity of the structure. Exact controllability theory is established using the Hilbert uniqueness method by means of a control torque applied only on the rigid hub of the panel. At the same time, uniform exponential energy decay rate is obtained directly for the solution of this problem. 相似文献
57.
58.
59.
This paper deals with the control of the class of singular nonlinear stochastic hybrid systems. Under some appropriate assumptions, results on stochastic stability and stochastic stabilization are developed. Two state feedback controllers (linear and nonlinear) that stochastically stabilize the class of systems we are considering are designed. LMI sufficient conditions are developed to compute the gains of these controllers. 相似文献
60.
We prove the existence and uniqueness of a global solution of a damped quasilineat hyperbolic equatiion. We apply a method based on a special integral inequality, to show that the solution decays exponentially, and to obtain precise estimates of the constants in estimates. 相似文献