全文获取类型
收费全文 | 416篇 |
免费 | 23篇 |
国内免费 | 31篇 |
专业分类
化学 | 19篇 |
晶体学 | 2篇 |
力学 | 4篇 |
综合类 | 18篇 |
数学 | 253篇 |
物理学 | 48篇 |
无线电 | 126篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 11篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 11篇 |
2016年 | 20篇 |
2015年 | 15篇 |
2014年 | 31篇 |
2013年 | 32篇 |
2012年 | 19篇 |
2011年 | 17篇 |
2010年 | 19篇 |
2009年 | 21篇 |
2008年 | 41篇 |
2007年 | 32篇 |
2006年 | 31篇 |
2005年 | 28篇 |
2004年 | 23篇 |
2003年 | 13篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 12篇 |
1999年 | 6篇 |
1998年 | 13篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
排序方式: 共有470条查询结果,搜索用时 750 毫秒
111.
Cesàro (C,δ) means are studied for orthogonal expansions with respect to the weight function
on the unit sphere, and for the corresponding weight functions on the unit ball and the Jacobi weight on the simplex. A sharp
pointwise estimate is established for the (C,δ) kernel with δ>−1 and for the kernel of the projection operator, which allows us to derive the exact order for the norm of the Cesàro means
and the projection operator on these domains.
相似文献
112.
In this paper we prove that the maximal operator of the Marcinkiewicz means of two-dimensional integrable functions with respect to the Walsh–Kaczmarz system is of weak type (1,1). Moreover, the Marcinkiewicz means converge to f almost everywhere, for any integrable function f. 相似文献
113.
In this paper, the influence of the noise and delay upon the stability property of reaction-diffusion recurrent neural networks (RNNs) with the time-varying delay is discussed. The new and easily verifiable conditions to guarantee the mean value exponential stability of an equilibrium solution are derived. The rate of exponential convergence can be estimated by means of a simple computation based on these criteria. 相似文献
114.
Baoguo Jia 《分析论及其应用》2006,22(4):362-376
By means of the idea of [2](Jia Baoguo,J.Math.Anal.Appl.In press) and the self.similarity of Sierpinski carpet, we obtain the lower and upper bounds of the Hausdorff Measure of Sierpinski carpet, which can approach the Hausdorff Measure of Sierpinski carpet infinitely. 相似文献
115.
G. A. Karagulyan 《Mathematical Notes》2006,80(1-2):47-56
For a function ? ∈, L 1( $\mathbb{T}$ ), we investigate the sequence (C, 1) of mean values Φ(¦S k (x, ?) ? ?(x)¦), where Φ(t): [0, +∞) → [0,+∞), Φ(0) = 0, is a continuous increasing function. We prove that if Φ increases faster than exponentially, then these means can diverge everywhere. Divergence almost everywhere of such means was established earlier. 相似文献
116.
This article for the first time develops a nonparametric methodology for the analysis of projective shapes of configurations of landmarks on real 3D objects from their regular camera pictures. A fundamental result in computer vision, emulating the principle of human vision in space, claims that, generically, a finite 3D configuration of points can be retrieved from corresponding configurations in a pair of camera images, up to a projective transformation. Consequently, the projective shape of a 3D configuration can be retrieved from two of its planar views, and a projective shape analysis can be pursued from a sample of images. Projective shapes are here regarded as points on projective shape manifolds. Using large sample and nonparametric bootstrap methodology for extrinsic means on manifolds, one gives confidence regions and tests for the mean projective shape of a 3D configuration from its 2D camera images. Two examples are given: an example of testing for accuracy of a simple manufactured object using mean projective shape analysis, and a face identification example. Both examples are data driven based on landmark registration in digital images. 相似文献
117.
118.
119.
为了研究常数磁场下的薛定谔算子的黎斯平均L2有界性问题,本文在Stein研究的Fowrier变换的工作基础上,通过研究Mpf(x),得到所要的估计. 相似文献
120.
借助于经典球面分析的Bochner-Riesz平均,Cesàro平均及有关球调和多项式的Gauss积分公式构造出了两类球面平移算子,并且以K-泛函为工具给出了逼近的上界估计. 相似文献