全文获取类型
收费全文 | 9486篇 |
免费 | 665篇 |
国内免费 | 642篇 |
专业分类
化学 | 623篇 |
晶体学 | 3篇 |
力学 | 501篇 |
综合类 | 187篇 |
数学 | 7422篇 |
物理学 | 2057篇 |
出版年
2024年 | 12篇 |
2023年 | 101篇 |
2022年 | 108篇 |
2021年 | 187篇 |
2020年 | 164篇 |
2019年 | 245篇 |
2018年 | 210篇 |
2017年 | 254篇 |
2016年 | 273篇 |
2015年 | 232篇 |
2014年 | 476篇 |
2013年 | 828篇 |
2012年 | 493篇 |
2011年 | 553篇 |
2010年 | 443篇 |
2009年 | 697篇 |
2008年 | 722篇 |
2007年 | 650篇 |
2006年 | 563篇 |
2005年 | 418篇 |
2004年 | 368篇 |
2003年 | 369篇 |
2002年 | 345篇 |
2001年 | 268篇 |
2000年 | 283篇 |
1999年 | 200篇 |
1998年 | 192篇 |
1997年 | 204篇 |
1996年 | 152篇 |
1995年 | 107篇 |
1994年 | 113篇 |
1993年 | 57篇 |
1992年 | 65篇 |
1991年 | 42篇 |
1990年 | 41篇 |
1989年 | 36篇 |
1988年 | 29篇 |
1987年 | 28篇 |
1986年 | 25篇 |
1985年 | 46篇 |
1984年 | 25篇 |
1983年 | 14篇 |
1982年 | 26篇 |
1981年 | 28篇 |
1980年 | 26篇 |
1979年 | 13篇 |
1978年 | 12篇 |
1977年 | 21篇 |
1976年 | 12篇 |
1975年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
We obtain exponential upper bounds for tails of distributions of generalized L-statistics based on a sample from an exponential distribution. We prove the asymptotic normality of generalized L-statistics based on a sample from the uniform distribution on [0,1] and of L-statistics with decomposed kernels (without any restrictions on the sample distribution type). 相似文献
32.
S. Mancini D. Vitali V. Giovannetti P. Tombesi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(3):417-422
We show that the optomechanical coupling between an optical cavity mode and two movable cavity mirrors is able to entangle
two different macroscopic oscillation modes of the mirrors. This continuous variable entanglement is maintained by the light
bouncing between the mirrors and is robust against thermal noise. In fact, it could be experimentally demonstrated using present
technology.
Received 2 September 2002 / Received in final form 10 October 2002 Published online 7 January 2003 相似文献
33.
M. A. Bertolim M. P. Mello K. A. de Rezende 《Transactions of the American Mathematical Society》2005,357(10):4091-4129
In this article the main theorem establishes the necessity and sufficiency of the Poincaré-Hopf inequalities in order for the Morse inequalities to hold. The convex hull of the collection of all Betti number vectors which satisfy the Morse inequalities for a pre-assigned index data determines a Morse polytope defined on the nonnegative orthant. Using results from network flow theory, a scheme is provided for constructing all possible Betti number vectors which satisfy the Morse inequalities for a pre-assigned index data. Geometrical properties of this polytope are described.
34.
On General Mixed Quasivariational Inequalities 总被引:5,自引:0,他引:5
In this paper, we suggest and analyze several iterative methods for solving general mixed quasivariational inequalities by using the technique of updating the solution and the auxiliary principle. It is shown that the convergence of these methods requires either the pseudomonotonicity or the partially relaxed strong monotonicity of the operator. Proofs of convergence is very simple. Our new methods differ from the existing methods for solving various classes of variational inequalities and related optimization problems. Various special cases are also discussed. 相似文献
35.
For vector quasivariational inequalities involving multifunctions in topological vector spaces, an existence result is obtained without a monotonicity assumption and with a convergence assumption weaker than semicontinuity. A new type of quasivariational inequality is proposed. Applications to quasicomplementarity problems and traffic network equilibria are considered. In particular, definitions of weak and strong Wardrop equilibria are introduced for the case of multivalued cost functions. 相似文献
36.
Li-ming Wu~ Zheng-liang Zhang~ Laboratoire de Mathématiques Appliquées.CNRS-UMR Université Blaise Pascal Aubière France 《应用数学学报(英文版)》2004,(3)
Using the method of Girsanov transformation,we establish the Talagrand's T_2-inequality for dif-fusion on the path space C([0,N],R~d) with respect to a uniform metric,with the constant independent of N.This improves the known results for the L~2-metric. 相似文献
37.
Thomas H. Pate 《Linear and Multilinear Algebra》2003,51(3):263-278
If 1≤k≤n, then Cor(n,k) denotes the set of all n×n real correlation matrices of rank not exceeding k. Grone and Pierce have shown that if A∈Cor (n, n-1), then per(A)≥n/(n-1). We show that if A∈Cor(n,2), then , and that this inequality is the best possible. 相似文献
38.
美式期权定价中非局部问题的有限元方法 总被引:2,自引:1,他引:1
在本文中 ,我们关心的是美式期权的有限元方法 .首先 ,根据 [4 ]我们对所讨论的问题引进一个新奇的实用的方法 ,它涉及到对原问题重新形成准确的数学公式 ,使得数值解的计算可以在非常小的区域上进行 ,从而该算法计算速度快精度高 .进而 ,我们利用超逼近分析技术得到了有限元解关于 L2 -模的最优估计 . 相似文献
39.
The projective method for solving linear matrix inequalities 总被引:2,自引:0,他引:2
Numerous problems in control and systems theory can be formulated in terms of linear matrix inequalities (LMI). Since solving
an LMI amounts to a convex optimization problem, such formulations are known to be numerically tractable. However, the interest
in LMI-based design techniques has really surged with the introduction of efficient interior-point methods for solving LMIs
with a polynomial-time complexity. This paper describes one particular method called the Projective Method. Simple geometrical
arguments are used to clarify the strategy and convergence mechanism of the Projective algorithm. A complexity analysis is
provided, and applications to two generic LMI problems (feasibility and linear objective minimization) are discussed. 相似文献
40.
具有奇异值分解性质的代数 总被引:4,自引:0,他引:4
设F为一个域,R为一个带有对合的F-代数,如果R上每一个矩阵都有奇异值分解(简称SVD),则称R为一个有SVD性质的F-代数.本文指出:R为一个有SVD性质的F-代数的充要条件是:R同构于R~+,或R~+上二次扩域,或R~+上四元数体((-1,-1)/R~+),其中R~+为R的对称元集合,并且R~+为一个Galois序闭域. 相似文献