全文获取类型
收费全文 | 5053篇 |
免费 | 338篇 |
国内免费 | 541篇 |
专业分类
化学 | 32篇 |
力学 | 167篇 |
综合类 | 85篇 |
数学 | 3271篇 |
物理学 | 208篇 |
综合类 | 2169篇 |
出版年
2024年 | 5篇 |
2023年 | 44篇 |
2022年 | 57篇 |
2021年 | 74篇 |
2020年 | 95篇 |
2019年 | 95篇 |
2018年 | 110篇 |
2017年 | 131篇 |
2016年 | 108篇 |
2015年 | 105篇 |
2014年 | 230篇 |
2013年 | 311篇 |
2012年 | 236篇 |
2011年 | 269篇 |
2010年 | 260篇 |
2009年 | 308篇 |
2008年 | 288篇 |
2007年 | 373篇 |
2006年 | 346篇 |
2005年 | 304篇 |
2004年 | 246篇 |
2003年 | 251篇 |
2002年 | 227篇 |
2001年 | 204篇 |
2000年 | 146篇 |
1999年 | 158篇 |
1998年 | 147篇 |
1997年 | 133篇 |
1996年 | 109篇 |
1995年 | 86篇 |
1994年 | 81篇 |
1993年 | 67篇 |
1992年 | 61篇 |
1991年 | 41篇 |
1990年 | 48篇 |
1989年 | 35篇 |
1988年 | 28篇 |
1987年 | 31篇 |
1986年 | 21篇 |
1985年 | 17篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1973年 | 2篇 |
1936年 | 4篇 |
排序方式: 共有5932条查询结果,搜索用时 93 毫秒
41.
G. A. Watson 《Advances in Computational Mathematics》1994,2(4):393-405
The orthogonal Procrustes problem involves finding an orthogonal matrix which transforms one given matrix into another in
the least-squares sense, and thus it requires the minimization of the Frobenius matrix norm. We consider, the solution of
this problem for a family of orthogonally invariant norms which includes the Frobenius norm as a special case. 相似文献
42.
通过构造新的辅助函数讨论Laplace算子的Dirichlet特征值估计,得到的不等式包含了已有的特征值估计,并可导得一些新的不等式。 相似文献
43.
S.V. Astashkin F.A. Sukochev 《Journal of Mathematical Analysis and Applications》2007,336(2):1231-1258
We catalogue all Marcinkiewicz function and sequence spaces with the Banach-Saks property and present necessary and sufficient conditions for a wide subclass of spaces to possess the p-Banach-Saks property, 1<p<∞. We apply our results to several open problems. 相似文献
44.
本文利用拟线性常微分方程解的非存在性定理得到了一类拟线性反应扩散方程(非牛顿渗流方程)爆破界的估计,从而推广了半线性反应扩散方程(牛顿渗流方程)相应结果. 相似文献
45.
Djavvat Khadjiev 《Journal of Mathematical Analysis and Applications》2007,326(2):1101-1115
An approach to a definition of an integral, which differs from definitions of Lebesgue and Henstock-Kurzweil integrals, is considered. We use trigonometrical polynomials instead of simple functions. Let V be the space of all complex trigonometrical polynomials without the free term. The definition of a continuous integral on the space V is introduced. All continuous integrals are described in terms of norms on V. The existence of the widest continuous integral is proved, the explicit form of its norm is obtained and it is proved that this norm is equivalent to the Alexiewicz norm. It is shown that the widest continuous integral is wider than the Lebesgue integral. An analog of the fundamental theorem of calculus for the widest continuous integral is given. 相似文献
46.
J. -R. Chazottes P. Collet C. Külske F. Redig 《Probability Theory and Related Fields》2007,137(1-2):201-225
We present a new and simple approach to concentration inequalities in the context of dependent random processes and random
fields. Our method is based on coupling and does not use information inequalities. In case one has a uniform control on the
coupling, one obtains exponential concentration inequalities. If such a uniform control is no more possible, then one obtains
polynomial or stretched-exponential concentration inequalities. Our abstract results apply to Gibbs random fields, both at
high and low temperatures and in particular to the low-temperature Ising model which is a concrete example of non-uniformity
of the coupling.
相似文献
47.
In this paper we derive a priori and a posteriori error estimates for cell centered finite volume approximations of nonlinear conservation laws on polygonal bounded domains. Numerical experiments show the applicability of the a posteriori result for the derivation of local adaptive solution strategies.
48.
I. N. Medvedev G. A. Mikhailov 《Computational Mathematics and Mathematical Physics》2006,46(8):1442-1458
The efficiency of the “value” and “partial value” modeling related to the construction of a modeling distribution for an auxiliary random variable by multiplying the initial density by a value function is investigated. The value function usually corresponds to a solution of the adjoint equation. Conditions under which the value modeling of the initial distribution reduces the variance compared to the direct simulation are obtained. It is proved that the variance of the weighted estimate is bounded in the case of the partial value modeling. This proposition provides a basis for a method for determining whether or not the variance of the weighted estimate is bounded. This method uses the majorizing adjoint equation. Using a practically important problem in transport theory as an example, the asymptotic optimization of the distribution of the mean free path is presented. The application of the proposed method of the investigation of the variance boundedness for the analysis of the classical exponential transformation method of simulating the mean free path of a particle in the one-dimensional and the spherical variants is discussed. 相似文献
49.
强混合样本下回归加权估计的一致渐近正态性 总被引:5,自引:0,他引:5
在强混合样本下,讨论固定设计回归模型的加权函数估计的一致渐近正态性,给出一致渐近正态性的收敛速度,这个速度接近n-1/6. 相似文献
50.
本文研究了两类重要微分不等式有界解的性质。引入了赋范线性空间(f,‖‖M),利用比较定理和黎卡提方程解的性质,给出了有界解的上界估计式,推广和改进了文[1,2]中的有关结果. 相似文献