全文获取类型
收费全文 | 918篇 |
免费 | 56篇 |
国内免费 | 124篇 |
专业分类
化学 | 3篇 |
力学 | 14篇 |
综合类 | 24篇 |
数学 | 1009篇 |
物理学 | 48篇 |
出版年
2024年 | 1篇 |
2023年 | 10篇 |
2022年 | 8篇 |
2021年 | 11篇 |
2020年 | 13篇 |
2019年 | 20篇 |
2018年 | 14篇 |
2017年 | 15篇 |
2016年 | 29篇 |
2015年 | 21篇 |
2014年 | 33篇 |
2013年 | 77篇 |
2012年 | 57篇 |
2011年 | 47篇 |
2010年 | 42篇 |
2009年 | 55篇 |
2008年 | 76篇 |
2007年 | 82篇 |
2006年 | 60篇 |
2005年 | 60篇 |
2004年 | 48篇 |
2003年 | 40篇 |
2002年 | 46篇 |
2001年 | 24篇 |
2000年 | 25篇 |
1999年 | 42篇 |
1998年 | 18篇 |
1997年 | 19篇 |
1996年 | 26篇 |
1995年 | 15篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 10篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 5篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有1098条查询结果,搜索用时 15 毫秒
1.
2.
In this paper, some endpoint estimates for the generalized multilinear fractional integrals I_(α,m) on the non-homogeneous metric spaces are established. 相似文献
3.
Ball convergence results are very important, since they demonstrate the complexity in choosing initial points for iterative methods. One of the most important problems in the study of iterative methods is to determine the convergence ball. This ball is small in general restricting the choice of initial points. We address this problem in the case of Wang’s method utilized to determine a zero of a derivative. Finding such a zero has many applications in computational fields, especially in function optimization. In particular, we find the convergence ball of Wang’s method using hypotheses up to the second derivative in contrast to earlier studies using hypotheses up to the fourth derivative. This way, we also extend the applicability of Wang’s method. Numerical experiments used to test the convergence criteria complete this study. 相似文献
4.
5.
6.
In this paper, we continue our investigation of polyharmonic mappings in the complex plane. First, we establish two Landau type theorems. We also show a three circles type theorem and an area version of the Schwarz lemma. Finally, we study Lipschitz continuity of polyharmonic mappings with respect to the distance ratio metric. 相似文献
7.
Numerical approximation of AR‐XPS spectra for rough surfaces considering the effect of electron shadowing 下载免费PDF全文
D. Bianchi L. Katona J. Brenner G. Vorlaufer A. Vernes W. S. M. Werner 《Surface and interface analysis : SIA》2015,47(1):15-21
A computational scheme is presented that takes into account the topography, i.e. the shadowing and hence the local emission angle of the electrons when evaluating AR‐XPS data of macroscopic rough surfaces. The topography of the sample surface is supposed to be recorded by atomic force microscopy and/or optical microscopy. The emitted photoelectrons are simulated based on an extension of the Beer–Lambert law that includes the shadowing, the current local emission angle, and the geometrical instrument setup. The obtained angle‐resolved XPS spectra are optimized in accordance with experimental ones via a self‐consistent minimization algorithm that also allows one to determine the layer thicknesses of the corrugated sample. In order to validate the proposed numerical scheme, the simulation program simulation of electron spectra for surface analysis is used. An additional analysis is then performed considering only experimental data. The numerical scheme gives good agreement in simulation–simulation as well as simulation–experiment comparisons and permits a comprehensible interpretation of the measured data. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
This paper mainly studies the problem of designing a hybrid state feedback D-admissible controller for a class of linear and nonlinear singular systems. Based on the relationship between singular discrete systems and singular delta operator systems, several necessary and sufficient conditions for a linear singular delta operator system to be D-admissible (i.e. regular, causal and all finite poles lie in a prescribed circular region) with different representations are derived. Then, the existence conditions and explicit expressions of a desirable D-admissible controller are given by means of matrix inequalities and strict linear matrix inequalities, respectively. We further extend the obtained results to singular delta operator systems with Lipschitz nonlinear perturbations, and the design methods of hybrid controller are presented for the nonlinear case as well. Finally, numerical examples as well as simulations are provided to illustrate the effectiveness of the theoretical outcomes obtained in the paper. 相似文献
9.
Global dynamics of nonautonomous diffusive Hindmarsh–Rose equations on a three-dimensional bounded domain in neurodynamics is investigated. The existence of a pullback attractor is proved through uniform estimates showing the pullback dissipative property and the pullback asymptotical compactness. Then the existence of pullback exponential attractor is also established by proving the smoothing Lipschitz continuity in a long run of the solution process. 相似文献
10.
Jun Jason Luo 《Mathematische Nachrichten》2019,292(5):1032-1042
Recently Lipschitz equivalence of self‐similar sets on has been studied extensively in the literature. However for self‐affine sets the problem is more awkward and there are very few results. In this paper, we introduce a w‐Lipschitz equivalence by repacing the Euclidean norm with a pseudo‐norm w. Under the open set condition, we prove that any two totally disconnected integral self‐affine sets with a common matrix are w‐Lipschitz equivalent if and only if their digit sets have equal cardinality. The main methods used are the technique of pseudo‐norm and Gromov hyperbolic graph theory on iterated function systems. 相似文献