全文获取类型
收费全文 | 1232篇 |
免费 | 117篇 |
国内免费 | 144篇 |
专业分类
化学 | 46篇 |
晶体学 | 12篇 |
力学 | 63篇 |
综合类 | 25篇 |
数学 | 1263篇 |
物理学 | 84篇 |
出版年
2024年 | 4篇 |
2023年 | 18篇 |
2022年 | 13篇 |
2021年 | 29篇 |
2020年 | 28篇 |
2019年 | 35篇 |
2018年 | 37篇 |
2017年 | 36篇 |
2016年 | 43篇 |
2015年 | 30篇 |
2014年 | 80篇 |
2013年 | 91篇 |
2012年 | 53篇 |
2011年 | 88篇 |
2010年 | 82篇 |
2009年 | 93篇 |
2008年 | 82篇 |
2007年 | 96篇 |
2006年 | 86篇 |
2005年 | 61篇 |
2004年 | 53篇 |
2003年 | 71篇 |
2002年 | 51篇 |
2001年 | 38篇 |
2000年 | 36篇 |
1999年 | 51篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1996年 | 19篇 |
1995年 | 6篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
排序方式: 共有1493条查询结果,搜索用时 15 毫秒
51.
Fré dé ric Bayart 《Proceedings of the American Mathematical Society》2003,131(6):1789-1791
We study the composition operators which are similar to an isometry on the classical Hardy space .
52.
Let be a space of homogeneous type, and be the generator of a semigroup with Gaussian kernel bounds on . We define the Hardy spaces of for a range of , by means of area integral function associated with the Poisson semigroup of , which is proved to coincide with the usual atomic Hardy spaces on spaces of homogeneous type.
53.
Let be a bounded domain such that . We obtain existence of sign-changing solutions for the Dirichlet problem on Ω,u=0 on ∂Ω for suitable positive numbers μ and λ. 相似文献
54.
Ramaz Botchorishvili Benoit Perthame Alexis Vasseur. 《Mathematics of Computation》2003,72(241):131-157
We consider a simple model case of stiff source terms in hyperbolic conservation laws, namely, the case of scalar conservation laws with a zeroth order source with low regularity. It is well known that a direct treatment of the source term by finite volume schemes gives unsatisfactory results for both the reduced CFL condition and refined meshes required because of the lack of accuracy on equilibrium states. The source term should be taken into account in the upwinding and discretized at the nodes of the grid. In order to solve numerically the problem, we introduce a so-called equilibrium schemes with the properties that (i) the maximum principle holds true; (ii) discrete entropy inequalities are satisfied; (iii) steady state solutions of the problem are maintained. One of the difficulties in studying the convergence is that there are no estimates for this problem. We therefore introduce a kinetic interpretation of upwinding taking into account the source terms. Based on the kinetic formulation we give a new convergence proof that only uses property (ii) in order to ensure desired compactness framework for a family of approximate solutions and that relies on minimal assumptions. The computational efficiency of our equilibrium schemes is demonstrated by numerical tests that show that, in comparison with an usual upwind scheme, the corresponding equilibrium version is far more accurate. Furthermore, numerical computations show that equilibrium schemes enable us to treat efficiently the sources with singularities and oscillating coefficients.
55.
E. G. Kwon 《Transactions of the American Mathematical Society》2003,355(3):1269-1294
We consider the hyperbolic Hardy class , . It consists of holomorphic in the unit complex ball for which and
where denotes the hyperbolic distance of the unit disc. The hyperbolic version of the Littlewood-Paley type -function and the area function are defined in terms of the invariant gradient of , and membership of is expressed by the property of the functions. As an application, we can characterize the boundedness and the compactness of the composition operator , defined by , from the Bloch space into the Hardy space .
where denotes the hyperbolic distance of the unit disc. The hyperbolic version of the Littlewood-Paley type -function and the area function are defined in terms of the invariant gradient of , and membership of is expressed by the property of the functions. As an application, we can characterize the boundedness and the compactness of the composition operator , defined by , from the Bloch space into the Hardy space .
56.
KunYuGUO 《数学学报(英文版)》2003,19(3):513-522
This paper is a brief and selective survey on classification of Hardy Submodules over the polydisk. The survey reports some progress in classification of Hardy submodules. 相似文献
57.
Remarks on Herz-Type Hardy Spaces 总被引:4,自引:0,他引:4
Akihiko Miyachi 《数学学报(英文版)》2001,17(2):339-360
Basic properties of the Herz-type Hardy spaces
, such as the boundedness of singular integral operators and the fractional integration operators, atomic decomposition, dense
subspaces, etc., are established in the full range 0 < q < ∞.
Partly supported by the Grants-in-Aid for Scientific Research (A)(1)11304009, (B)(1)10440046, Japan Society
for the Promotion of Science. 相似文献
58.
Yu. A. Farkov 《Mathematical Notes》2000,68(2):248-254
Suppose thatB
R
d
is a ball of radiusR in ℂ
d
and σ is the standard measure on the unit sphere in ℂ
d
. ForR>1, 1≤p≤∞, and for the natural numbersl, d, byH
R
0
(l, p, d) we denote the class of functionsf holomorphic inB
R
d
and such that in the homogeneous polynomial expansion of the firstl summands the zero and radial derivatives of orderl belong to the closed unit ball of the Hardy spaceH
p
(B
R
d
). In this paper an asymptotic formula for the ε-entropy of the classH
R
0
(l, p, d) in the spacesL
p
(σ), 1≤p<∞, and
is obtained.
Translated fromMatematicheskie Zametki, Vol. 68, No. 2, pp. 286–293, August, 2000. 相似文献
59.
Valerio Caleffi 《国际流体数值方法杂志》2011,67(9):1135-1159
Hermite weighted essentially non‐oscillatory (HWENO) methods were introduced in the literature, in the context of Euler equations for gas dynamics, to obtain high‐order accuracy schemes characterized by high compactness (e.g. Qiu and Shu, J. Comput. Phys. 2003; 193 :115). For example, classical fifth‐order weighted essentially non‐oscillatory (WENO) reconstructions are based on a five‐cell stencil whereas the corresponding HWENO reconstructions are based on a narrower three‐cell stencil. The compactness of the schemes allows easier treatment of the boundary conditions and of the internal interfaces. To obtain this compactness in HWENO schemes both the conservative variables and their first derivatives are evolved in time, whereas in the original WENO schemes only the conservative variables are evolved. In this work, an HWENO method is applied for the first time to the shallow water equations (SWEs), including the source term due to the bottom slope, to obtain a fourth‐order accurate well‐balanced compact scheme. Time integration is performed by a strong stability preserving the Runge–Kutta method, which is a five‐step and fourth‐order accurate method. Besides the classical SWE, the non‐homogeneous equations describing the time and space evolution of the conservative variable derivatives are considered here. An original, well‐balanced treatment of the source term involved in such equations is developed and tested. Several standard one‐dimensional test cases are used to verify the high‐order accuracy, the C‐property and the good resolution properties of the model. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
60.
The work strengthens the result established by L. Cohen on uncertainty principle involving phase derivative. We propose stronger uncertainty principles not only in the classical setting for Fourier transform, but also for self-adjoint operators. We also deduce the conditions that give rise to the equal relation of the uncertainty principle. Examples are provided to show that the new uncertainty principle is truly sharper than the existing ones in literature. 相似文献