全文获取类型
收费全文 | 2453篇 |
免费 | 177篇 |
国内免费 | 187篇 |
专业分类
化学 | 94篇 |
晶体学 | 1篇 |
力学 | 42篇 |
综合类 | 18篇 |
数学 | 2463篇 |
物理学 | 199篇 |
出版年
2024年 | 4篇 |
2023年 | 39篇 |
2022年 | 27篇 |
2021年 | 40篇 |
2020年 | 71篇 |
2019年 | 95篇 |
2018年 | 71篇 |
2017年 | 72篇 |
2016年 | 79篇 |
2015年 | 61篇 |
2014年 | 124篇 |
2013年 | 204篇 |
2012年 | 83篇 |
2011年 | 148篇 |
2010年 | 113篇 |
2009年 | 168篇 |
2008年 | 194篇 |
2007年 | 152篇 |
2006年 | 164篇 |
2005年 | 111篇 |
2004年 | 110篇 |
2003年 | 106篇 |
2002年 | 101篇 |
2001年 | 82篇 |
2000年 | 73篇 |
1999年 | 66篇 |
1998年 | 49篇 |
1997年 | 61篇 |
1996年 | 28篇 |
1995年 | 21篇 |
1994年 | 18篇 |
1993年 | 12篇 |
1992年 | 14篇 |
1991年 | 8篇 |
1990年 | 4篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有2817条查询结果,搜索用时 970 毫秒
31.
Frank N. Proske Madan L. Puri 《Proceedings of the American Mathematical Society》2003,131(9):2937-2944
In this article we prove a strong law of large numbers for Borel measurable nonseparably valued random elements in the case of generalized random sets.
32.
The educational system has gradually shifted from a face-to-face to an e-learning system, which has become prevalent in advanced countries with the advance of information technology, and connection of global networks. Accordingly, a growing demand is emerging for more reliable individual certification with technical precision in order to measure and record learning achievements and credentials of participants. The present system has a limit in terms of registration capacity, therefore, its accuracy has often been questioned. Against this background, an individual certification system is proposed particularly for access control in e-learning. Under our proposed system, a compact optical correlator for facial recognition is employed. This correlator was previously tested for of biometrics authentication accuracy and proved highly reliable, having recorded remarkably low error rates (below 1%). The recorded error rate is sufficiently robust that the system itself can be regarded as a valid and practical viable attestation system. 相似文献
33.
We prove a general embedding theorem for Sobolev spaces on open manifolds of bounded geometry and infer from this the module structure theorem. Thereafter we apply this to weighted Sobolev spaces. 相似文献
34.
We investigate the links between Sobolev and Nash inequalities, capacity and hitting times estimates and ultracontractive semigroups, in a non-symmetric setting. 相似文献
35.
R. S. Ismagilov 《Mathematical Notes》1997,62(2):186-197
We present simple proofs of the possibility of embedding ultrametric spaces in Hilbert spaces. The main part of the paper
deals with ultrametric spaces that we call totally infinite spaces. Related Hilbert spaces, automorphisms of totally infinite
spaces, and the corresponding linear operators are considered.
Transplated fromMatematicheskie Zametki, Vol. 62, No. 2, pp. 223–237, August, 1997.
Translated by V. E. Nazaikinskii 相似文献
36.
Vladimir P. Korzhik 《Discrete Mathematics》1998,190(1-3):149-162
The author has proposed methods of constructing index 2 and 3 current graphs generating triangular embeddings of graphs Kn−Km with unboundedly large m (as n increases). As a result, triangular embeddings of graphs of many families of graphs Kn−Km with unboundedly large m were constructed. The paper gives a survey of these results and a short explanation of the methods. 相似文献
37.
Shigeki Aida 《Journal of Functional Analysis》2007,251(1):59-121
We determine the limit of the bottom of spectrum of Schrödinger operators with variable coefficients on Wiener spaces and path spaces over finite-dimensional compact Riemannian manifolds in the semi-classical limit. These are extensions of the results in [S. Aida, Semiclassical limit of the lowest eigenvalue of a Schrödinger operator on a Wiener space, J. Funct. Anal. 203 (2) (2003) 401-424]. The problem on path spaces over Riemannian manifolds is considered as a problem on Wiener spaces by using Ito's map. However the coefficient operator is not a bounded linear operator and the dependence on the path is not continuous in the uniform convergence topology if the Riemannian curvature tensor on the underling manifold is not equal to 0. The difficulties are solved by using unitary transformations of the Schrödinger operators by approximate ground state functions and estimates in the rough path analysis. 相似文献
38.
Mathematical Notes - 相似文献
39.
We investigate traces of functions, belonging to a class of functions with dominating mixed smoothness in ℝ3, with respect to planes in oblique position. In comparison with the classical theory for isotropic spaces a few new phenomenona
occur. We shall present two different approaches. One is based on the use of the Fourier transform and restricted to p = 2. The other one is applicable in the general case of Besov-Lizorkin-Triebel spaces and based on atomic decompositions. 相似文献
40.
Frédéric Mynard 《Topology and its Applications》2007,154(4):953-968
Two results on product of compact filters are shown to be the common principle behind a surprisingly large number of theorems. 相似文献