全文获取类型
收费全文 | 891篇 |
免费 | 38篇 |
国内免费 | 131篇 |
专业分类
化学 | 5篇 |
力学 | 29篇 |
综合类 | 10篇 |
数学 | 985篇 |
物理学 | 31篇 |
出版年
2024年 | 2篇 |
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 6篇 |
2020年 | 13篇 |
2019年 | 24篇 |
2018年 | 22篇 |
2017年 | 14篇 |
2016年 | 24篇 |
2015年 | 21篇 |
2014年 | 46篇 |
2013年 | 61篇 |
2012年 | 39篇 |
2011年 | 37篇 |
2010年 | 50篇 |
2009年 | 63篇 |
2008年 | 59篇 |
2007年 | 71篇 |
2006年 | 84篇 |
2005年 | 38篇 |
2004年 | 35篇 |
2003年 | 40篇 |
2002年 | 43篇 |
2001年 | 24篇 |
2000年 | 35篇 |
1999年 | 31篇 |
1998年 | 41篇 |
1997年 | 27篇 |
1996年 | 21篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 2篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 1篇 |
排序方式: 共有1060条查询结果,搜索用时 31 毫秒
981.
Pando Gr. Georgiev 《Set-Valued Analysis》1997,5(1):1-35
The notions submonotone and strictly submonotone mapping, introduced by J. Spingarn in
n
, are extended in a natural way to arbitrary Banach spaces. Several results about monotone operators are proved for submonotone and strictly submonotone ones: Rockafellar's result about local boundedness of monotone operators; Kenderov's result about single-valuedness and upper-semicontinuity almost everywhere of monotone operators in Asplund spaces; minimality (w*-cusco mappings) of maximal strictly submonotone mappings, etc. It is shown that subdifferentials of various classes of nonconvex functions defined as pointwise suprema of quasi-differentiable functions possess submonotone properties. Results about generic differentiability of such functions are obtained (among them are new generalizations of an Ekeland and Lebourg's theorem). Applications are given to the properties of the distance function in a Banach space with a uniformly Gateaux differentiable norm. 相似文献
982.
Li Zhong 《Proceedings of the American Mathematical Society》1996,124(5):1459-1465
In this paper we construct a closed geodesic in any infinite-
dimensional Teichmüller space. The construction also leads to a proof of non-differentiability of the metric in infinite-dimensional Teichmüller spaces, which provides a negative answer to a problem of Goldberg.
dimensional Teichmüller space. The construction also leads to a proof of non-differentiability of the metric in infinite-dimensional Teichmüller spaces, which provides a negative answer to a problem of Goldberg.
983.
Andrzej Wisniewski 《Proceedings of the American Mathematical Society》1996,124(12):3703-3710
The purpose of this paper is to describe these -measurable mappings on a separable complete metric space with the Borel measure , which transform every -measurable set onto a -measurable one. The obtained results are a generalization of the classical outcomes of Suslin and Kuratowski and the results from our previous paper.
984.
We prove a generalization of Brouwer's famous fixed point theorem to discontinuous maps. The main result shows that for discontinuous functions on a compact convex domainX one can always find a pointx X such that x–f(x) is less than a certain measure of discontinuity. Applications to artificial neural nets, economic equilibria and analysis are given. 相似文献
985.
P. I. Katsylo 《Mathematical Notes》1998,63(4):464-470
Two results on the degrees of polynomial mappings 22 are obtained.Translated fromMatematicheskie Zametki, Vol. 63, No. 4, pp. 527–534, April, 1998. 相似文献
986.
We consider transversal (orthogonal) perturbations of finite-dimensional convex sets and estimate the degree of nonconvexity of resulting sets, i.e. we estimate the nonconvexity of graphs of continuous functions. We prove that a suitable estimate of nonconvexity of graphs over all lines induces a nice estimate of the nonconvexity of graphs of the entire function. Here, the term nice means that in the well-known Michael selection theorem it is possible to replace convex sets of a multivalued mapping by such nonconvex sets. As a corollary, we obtain positive results for polynomials of degree two under some restrictions on coefficients. Our previous results concerned the polynomials of degree one and Lipschitz functions. We show that for a family of polynomials of degree three such estimate of convexity in general does not exist. Moreover, for degree 9 we show that the nonconvexity of the unique polynomial P(x,y)=x9+x3y realizes the worst possible case. 相似文献
987.
In a paper we proved the following fixed point theorem: Every strictly contracting map F:X X of a spherically complete ultrametric space X has a unique fixed point x, that is, F(x) = x. In this paper we study conditions for two self-maps F, G of an ultrametric space to have a common point x, i.e. F(x) = G(x). 相似文献
988.
本文研究了一类涉及渐近拟非扩张型映象的带误改进Mann迭代序列,利用Tan和Xu的不等式,得到了该带误差Mann迭代序列的稳定性,推广了其他人的结果. 相似文献
989.
990.
渐近半压缩映象的收敛性定理 总被引:1,自引:0,他引:1
胡良根 《宁波大学学报(理工版)》2008,21(4):514-519
在任意的赋范线性空间中,通过使用新的分析技巧研究了渐近伪压缩映象和渐近半压缩映象带误差的三步迭代序列的几个强收敛性定理.文中不仅包括了修正的带误差的Mann和Ishikawa迭代序列的收敛性结果作为2种特殊情况,同时证明了序列收敛的充分必要条件,且证明方法更为简单. 相似文献