全文获取类型
收费全文 | 4592篇 |
免费 | 449篇 |
国内免费 | 462篇 |
专业分类
化学 | 257篇 |
晶体学 | 15篇 |
力学 | 285篇 |
综合类 | 112篇 |
数学 | 4138篇 |
物理学 | 696篇 |
出版年
2024年 | 3篇 |
2023年 | 60篇 |
2022年 | 78篇 |
2021年 | 92篇 |
2020年 | 137篇 |
2019年 | 133篇 |
2018年 | 138篇 |
2017年 | 137篇 |
2016年 | 147篇 |
2015年 | 98篇 |
2014年 | 202篇 |
2013年 | 404篇 |
2012年 | 189篇 |
2011年 | 242篇 |
2010年 | 227篇 |
2009年 | 282篇 |
2008年 | 291篇 |
2007年 | 308篇 |
2006年 | 304篇 |
2005年 | 271篇 |
2004年 | 228篇 |
2003年 | 206篇 |
2002年 | 210篇 |
2001年 | 166篇 |
2000年 | 151篇 |
1999年 | 142篇 |
1998年 | 106篇 |
1997年 | 90篇 |
1996年 | 84篇 |
1995年 | 66篇 |
1994年 | 66篇 |
1993年 | 32篇 |
1992年 | 31篇 |
1991年 | 21篇 |
1990年 | 23篇 |
1989年 | 7篇 |
1988年 | 12篇 |
1987年 | 11篇 |
1986年 | 23篇 |
1985年 | 23篇 |
1984年 | 15篇 |
1983年 | 13篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 2篇 |
1978年 | 4篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1957年 | 3篇 |
1936年 | 1篇 |
排序方式: 共有5503条查询结果,搜索用时 31 毫秒
11.
Manuel
Bernard Ghislain Lartigue Guillaume Balarac Vincent Moureau Guillaume Puigt 《国际流体数值方法杂志》2020,92(11):1551-1583
In this article, a new framework to design high-order approximations in the context of node-centered finite volumes on simplicial meshes is proposed. The major novelty of this method is that it relies on very simple and compact differential operators, which is a critical point to achieve good performances in the High-performance computing context. This method is based on deconvolution between nodal and volume-average values, which can be conducted to any order. The interest of the new method is illustrated through three different applications: mesh-to-mesh interpolation, levelset curvature computation, and numerical scheme for convection. Higher order can also be achieved within the present framework by introducing high-rank tensors. Although these tensors feature much symmetries, their manipulation can quickly become an overwhelming task. For this reason and without loss of generality, the present articles are limited to third-order expansion. This method, although tightly connected to the k-exact schemes theory, does not rely on successive corrections: the high-order property is obtained in a single operation, which makes them more attractive in terms of performances. 相似文献
12.
13.
14.
15.
We consider the problem of sending a message from a sender to a receiver through an unreliable network by specifying in a protocol what each vertex is supposed to do if it receives the message from one of its neighbors. A protocol for routing a message in such a graph is finite if it never floods with an infinite number of copies of the message. The expected reliability of a given protocol is the probability that a message sent from reaches when the edges of the network fail independently with probability .We discuss, for given networks, the properties of finite protocols with maximum expected reliability in the case when is close to 0 or 1, and we describe networks for which no one protocol is optimal for all values of . In general, finding an optimal protocol for a given network and fixed probability is challenging and many open problems remain. 相似文献
16.
Bobby Wilson 《偏微分方程通讯》2015,40(8):1521-1542
This article explores the questions of long time orbital stability in high order Sobolev norms of plane wave solutions to the NLSE in the defocusing case. 相似文献
17.
We generalize Nagel’s formula for the Szegö kernel and use it to compute the Szegö kernel on a class of non-compact CR manifolds whose tangent space decomposes into one complex direction and several totally real directions. We also discuss the control metric on these manifolds and relate it to the size of the Szegö kernel. 相似文献
18.
19.
Anton Schiela 《Numerical Functional Analysis & Optimization》2019,40(1):85-118
We propose a cubic regularization algorithm that is constructed to deal with nonconvex minimization problems in function space. It allows for a flexible choice of the regularization term and thus accounts for the fact that in such problems one often has to deal with more than one norm. Global and local convergence results are established in a general framework. 相似文献
20.
Marién Abreu Jan Goedgebeur Domenico Labbate Giuseppe Mazzuoccolo 《Journal of Graph Theory》2019,92(4):415-444
A -bisection of a bridgeless cubic graph is a -colouring of its vertex set such that the colour classes have the same cardinality and all connected components in the two subgraphs induced by the colour classes ( monochromatic components in what follows) have order at most . Ban and Linial Conjectured that every bridgeless cubic graph admits a -bisection except for the Petersen graph. A similar problem for the edge set of cubic graphs has been studied: Wormald conjectured that every cubic graph with has a -edge colouring such that the two monochromatic subgraphs are isomorphic linear forests (ie, a forest whose components are paths). Finally, Ando conjectured that every cubic graph admits a bisection such that the two induced monochromatic subgraphs are isomorphic. In this paper, we provide evidence of a strong relation of the conjectures of Ban-Linial and Wormald with Ando's Conjecture. Furthermore, we also give computational and theoretical evidence in their support. As a result, we pose some open problems stronger than the above-mentioned conjectures. Moreover, we prove Ban-Linial's Conjecture for cubic-cycle permutation graphs. As a by-product of studying -edge colourings of cubic graphs having linear forests as monochromatic components, we also give a negative answer to a problem posed by Jackson and Wormald about certain decompositions of cubic graphs into linear forests. 相似文献