全文获取类型
收费全文 | 1318篇 |
免费 | 64篇 |
国内免费 | 102篇 |
专业分类
化学 | 23篇 |
力学 | 19篇 |
综合类 | 8篇 |
数学 | 1353篇 |
物理学 | 81篇 |
出版年
2023年 | 14篇 |
2022年 | 14篇 |
2021年 | 12篇 |
2020年 | 25篇 |
2019年 | 32篇 |
2018年 | 27篇 |
2017年 | 25篇 |
2016年 | 28篇 |
2015年 | 27篇 |
2014年 | 46篇 |
2013年 | 114篇 |
2012年 | 41篇 |
2011年 | 43篇 |
2010年 | 47篇 |
2009年 | 63篇 |
2008年 | 87篇 |
2007年 | 79篇 |
2006年 | 69篇 |
2005年 | 60篇 |
2004年 | 48篇 |
2003年 | 49篇 |
2002年 | 50篇 |
2001年 | 48篇 |
2000年 | 41篇 |
1999年 | 32篇 |
1998年 | 40篇 |
1997年 | 32篇 |
1996年 | 18篇 |
1995年 | 9篇 |
1994年 | 19篇 |
1993年 | 13篇 |
1992年 | 8篇 |
1991年 | 10篇 |
1990年 | 17篇 |
1989年 | 9篇 |
1988年 | 4篇 |
1987年 | 12篇 |
1986年 | 5篇 |
1985年 | 14篇 |
1984年 | 10篇 |
1983年 | 12篇 |
1982年 | 20篇 |
1981年 | 10篇 |
1980年 | 17篇 |
1979年 | 17篇 |
1978年 | 11篇 |
1977年 | 17篇 |
1976年 | 22篇 |
1975年 | 4篇 |
1974年 | 7篇 |
排序方式: 共有1484条查询结果,搜索用时 31 毫秒
41.
Davit Varron 《Stochastic Processes and their Applications》2011,121(2):337-356
Given an observation of the uniform empirical process αn, its functional increments αn(u+an⋅)−αn(u) can be viewed as a single random process, when u is distributed under the Lebesgue measure. We investigate the almost sure limit behaviour of the multivariate versions of these processes as n→∞ and an↓0. Under mild conditions on an, a convergence in distribution and functional limit laws are established. The proofs rely on a new extension of the usual Poissonisation tools for the local empirical process. 相似文献
42.
具有特殊伸缩矩阵的三元不可分正交小波的构造 总被引:1,自引:0,他引:1
多元小波分析是分析和处理多维数字信号的有力工具.不可分多元小波被广泛地应用在模式识别、纹理分析和边缘检测等领域.给出了构造具有伸缩矩阵(101-1-110-10)的紧支撑三元不可分正交小波的算法,利用该算法得到的小波函数继承了来源于尺度函数和符号函数的对称性和消失矩性质,从而为这类小波在信号处理方面的应用提供了便利.最后给出了数值算例. 相似文献
43.
New Results on Generalized $c$-Distance Without Continuity in Cone $b$-Metric Spaces over Banach Algebras 下载免费PDF全文
Yan Han & Shaoyuan Xu 《分析论及其应用》2022,38(3):335-350
In this work, some new fixed point results for generalized Lipschitz mappings on generalized $c$-distance in cone $b$-metric spaces over Banach algebras are obtained, not acquiring the condition that the underlying cone should be normal or the
mappings should be continuous. Furthermore, the existence and the uniqueness of the
fixed point are proven for such mappings. These results greatly improve and generalize several well-known comparable results in the literature. Moreover, some examples
and an application are given to support our new results. 相似文献
44.
In this paper we define a lattice order on a set F of binary functions. We then provide necessary and sufficient conditions for the resulting algebra
F to be a distributive lattice or a Boolean algebra. We also prove a Cayley theorem for distributive lattices by showing that for every distributive lattice
, there is an algebra
F of binary functions, such that
is isomorphic to
F and we show that
F is a distributive lattice iff the operations and are idempotent and cummutative, showing that this result cannot be generalized to non-distributive lattices or quasilattices without changing the definitions of and . We also examine the equational properties of an Algebra
for which
, now defined on the set of binary
-polynomials is a lattice or Boolean algebra. 相似文献
45.
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
46.
In 1978 De Giorgi formulated the following conjecture. Let be a solution of in all of such that and 0$"> in . Is it true that all level sets of are hyperplanes, at least if ? Equivalently, does depend only on one variable? When , this conjecture was proved in 1997 by N. Ghoussoub and C. Gui. In the present paper we prove it for . The question, however, remains open for . The results for and 3 apply also to the equation for a large class of nonlinearities .
47.
二阶奇异微分方程组边值问题两个正解的存在性 总被引:1,自引:0,他引:1
利用锥拉伸和锥压缩不动点定理,给出了一类二阶微分方程组奇异边值问题两个正解的存在性. 相似文献
48.
Z.W. Yang M.Z. Liu Juan J. Nieto 《Journal of Computational and Applied Mathematics》2009,233(4):990-1004
In this paper we deal with the numerical solutions of Runge–Kutta methods for first-order periodic boundary value differential equations with piecewise constant arguments. The numerical solution is given by the numerical Green’s function. It is shown that Runge–Kutta methods preserve their original order for first-order periodic boundary value differential equations with piecewise constant arguments. We give the conditions under which the numerical solutions preserve some properties of the analytic solutions, e.g., uniqueness and comparison theorems. Finally, some experiments are given to illustrate our results. 相似文献
49.
50.
We prove a comparison theorem extending Li(6) and develop a complex-analytic approach to treat L
2 small ball probabilities of Gaussian processes. We demonstrate the techniques for the m-times integrated Brownian motions and in examples where one can not apply Li comparison theorem. 相似文献