全文获取类型
收费全文 | 961篇 |
免费 | 58篇 |
国内免费 | 72篇 |
专业分类
化学 | 90篇 |
力学 | 27篇 |
综合类 | 10篇 |
数学 | 736篇 |
物理学 | 228篇 |
出版年
2024年 | 1篇 |
2023年 | 11篇 |
2022年 | 15篇 |
2021年 | 17篇 |
2020年 | 20篇 |
2019年 | 24篇 |
2018年 | 24篇 |
2017年 | 31篇 |
2016年 | 38篇 |
2015年 | 26篇 |
2014年 | 43篇 |
2013年 | 97篇 |
2012年 | 35篇 |
2011年 | 56篇 |
2010年 | 52篇 |
2009年 | 90篇 |
2008年 | 73篇 |
2007年 | 50篇 |
2006年 | 53篇 |
2005年 | 40篇 |
2004年 | 36篇 |
2003年 | 40篇 |
2002年 | 24篇 |
2001年 | 28篇 |
2000年 | 38篇 |
1999年 | 12篇 |
1998年 | 29篇 |
1997年 | 18篇 |
1996年 | 15篇 |
1995年 | 14篇 |
1994年 | 10篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1979年 | 3篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有1091条查询结果,搜索用时 31 毫秒
81.
We solve a boundary interpolation problem in the reproducing kernel Hilbert space of functions analytic in the unit ball of
with reproducing kernel 1/(1−∑1Nzkwk*). We introduce the notion of Brune factor (or Blaschke–Potapov factor of the third kind) in this setting. 相似文献
82.
83.
本文研究了两种不同系统因素影响下完全检验的质量最优问题 ,采用有两种不同控制界限的控制图来控制生产过程 ,并根据完全检验的特点 ,提出了一种新的最优模型。 Hui(1 991 )提出的最优模型是本文的最优模型的特殊情况 ,并且本文建立的最优模型还可推广到两种以上不同的系统因素下影响的情况 相似文献
84.
Ralf Korn 《Applied Mathematical Finance》2013,20(1):65-79
We consider the problem of L 2-hedging of contingent claims in diffusion type models for securities markets. In contrast to a recent paper of Schweizer (1994) we insist on a non-negative wealth process corresponding to the optimal hedge portfolio. For this reason the usual projection methods cannot be applied. We give some applications of L 2-hedging in this setting including hedging under constraints, a problem of approximating the wealth process of a richer investor and a mean-variance version of it. 相似文献
85.
Ljubomir ?iri? Vladimir Rako?evi? 《Journal of Computational and Applied Mathematics》2010,233(11):2966-5789
In this paper, the concept of a pair of non-linear contraction type mappings in a metric space of hyperbolic type is introduced and the conditions guaranteeing the existence of a common fixed point for such non-linear contractions are established. Presented results generalize and improve some of the known results. An example is constructed to show that our theorems are genuine generalizations of the main theorems of Assad, ?iri?, Khan et al., Rhoades and Imdad and Kumar. One of the possible applications of our results is also presented. 相似文献
86.
We address the problem of sequentially inspecting the dependent characteristics of a product, where the dependency is expressed in terms of the joint probabilities of the fitness of the characteristics. We show that, even when the inspection has classification errors, the joint probability mass function of the observed fitness of the characteristics is independent of the sequence of inspection. Using this result, a dynamic programming approach is presented for finding the optimal sequence that minimizes the expected total cost of inspection. Previously reported policies for independent characteristics are shown to be special cases of the results presented here. 相似文献
87.
Ma?gorzata Zwonek 《Discrete Mathematics》2006,306(18):2282-2291
In the paper two different arc-colourings and two associated with the total colourings of digraphs are considered. In one of these colourings we show that the problem of calculating the total chromatic index reduces to that of calculating the chromatic number of the underlying graph. In the other colouring we find the total chromatic indices of complete symmetric digraphs and tournaments. 相似文献
88.
David R. Wood 《Graphs and Combinatorics》2007,23(3):337-352
A clique is a set of pairwise adjacent vertices in a graph. We determine the maximum number of cliques in a graph for the following
graph classes: (1) graphs with n vertices and m edges; (2) graphs with n vertices, m edges, and maximum degree Δ; (3) d-degenerate graphs with n vertices and m edges; (4) planar graphs with n vertices and m edges; and (5) graphs with n vertices and no K5-minor or no K3,3-minor. For example, the maximum number of cliques in a planar graph with n vertices is 8(n − 2).
Research supported by a Marie Curie Fellowship of the European Community under contract 023865, and by the projects MCYT-FEDER
BFM2003-00368 and Gen. Cat 2001SGR00224. 相似文献
89.
可加的广义代数格范畴与 T0 拓扑空间范畴相等价, 从这个观点出发, 作者把可加广义代数格作为一个闭集格, 在其上建立 Urysohn 引理和 Tietze 扩张定理. 这是拓扑理论在格上的一种新推广, 有助于格上拓扑理论的研究和广义连续格理论的应用. 相似文献
90.
该文给出:对于偶数m≥4当n→ ∞时 r(Wm,Kn)≤l(1+o(1))C1(m) (n/logn ) (2m-2)/(m-2)对于奇数m≥5当n→∞时r(Wm,Kn)≤(1+o(1))C2(m) (n2m/m+1/log n)(m+1)/(m-1) .特别地,C2(5)=12. 以及 c(n/logn)5/2≤r(K4,Kn)≤ (1+o(1)) n3/(logn)2.此外,该文还讨论了轮和完全图的 Ramsey 数的一些推广. 相似文献