全文获取类型
收费全文 | 837篇 |
免费 | 162篇 |
国内免费 | 44篇 |
专业分类
化学 | 44篇 |
力学 | 262篇 |
综合类 | 4篇 |
数学 | 503篇 |
物理学 | 230篇 |
出版年
2023年 | 15篇 |
2022年 | 2篇 |
2021年 | 14篇 |
2020年 | 31篇 |
2019年 | 43篇 |
2018年 | 28篇 |
2017年 | 34篇 |
2016年 | 32篇 |
2015年 | 33篇 |
2014年 | 55篇 |
2013年 | 93篇 |
2012年 | 61篇 |
2011年 | 63篇 |
2010年 | 31篇 |
2009年 | 52篇 |
2008年 | 56篇 |
2007年 | 39篇 |
2006年 | 40篇 |
2005年 | 40篇 |
2004年 | 55篇 |
2003年 | 43篇 |
2002年 | 27篇 |
2001年 | 20篇 |
2000年 | 19篇 |
1999年 | 16篇 |
1998年 | 15篇 |
1997年 | 14篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 3篇 |
1993年 | 5篇 |
1992年 | 12篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有1043条查询结果,搜索用时 15 毫秒
81.
Superconvergence of the direct discontinuous Galerkin method for convection‐diffusion equations
下载免费PDF全文
![点击此处可从《Numerical Methods for Partial Differential Equations》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Waixiang Cao Hailiang Liu Zhimin Zhang 《Numerical Methods for Partial Differential Equations》2017,33(1):290-317
This paper is concerned with superconvergence properties of the direct discontinuous Galerkin (DDG) method for one‐dimensional linear convection‐diffusion equations. We prove, under some suitable choice of numerical fluxes and initial discretization, a 2k‐th and ‐th order superconvergence rate of the DDG approximation at nodes and Lobatto points, respectively, and a ‐th order of the derivative approximation at Gauss points, where k is the polynomial degree. Moreover, we also prove that the DDG solution is superconvergent with an order k + 2 to a particular projection of the exact solution. Numerical experiments are presented to validate the theoretical results. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 290–317, 2017 相似文献
82.
83.
二维边界元奇异积分和多域缩聚法分析 总被引:2,自引:1,他引:2
基于基本解的一种新的表达式,对二维边界元分析中奇异积分的精确求解进行了讨论,从几何方面对基本解的奇异性进行了分析,给出了超参非连续元离散位势和弹性力学问题边界积分方程时奇异积分计算的精确式,从而为判断各种近似方法的优劣和间接方法的精度提供了依据,也为精确地分析了大规模问题提供了一条有效的途径。 相似文献
84.
非连续边界元——有限元耦合方法分析 总被引:4,自引:0,他引:4
对边界元-有限元耦合方法进行了分析,采用非连续元离散边界积分方程,解决了耦合分析中自由度约束问题,给出了非连续边界元同有限元耦合的具体实施步骤,通过对二维弹性力学和流=固耦合问题分析,表明了该文方法的有效性。 相似文献
85.
The nonlinear propagation of modified electron‐acoustic (mEA) shock waves in an unmagnetized, collisionless, relativistic, degenerate quantum plasma (containing non‐relativistic degenerate inertial cold electrons, both nonrelativistic and ultra‐relativistic degenerate hot electron and inertial positron fluids, and positively charged static ions) has been investigated theoretically. The well‐known Burgers type equation has been derived for both planar and nonplanar geometry by employing the reductive perturbation method. The shock wave solution has also been obtained and numerically analyzed. It has been observed that the mEA shock waves are significantly modified due to the effects of degenerate pressure and other plasma parameters arised in this investigation. The properties of planar Burgers shocks are quite different from those of nonplanar Burgers shocks. The basic features and the underlying physics of shock waves, which are relevant to some astrophysical compact objects (viz. non‐rotating white dwarfs, neutron stars, etc.), are briefly discussed. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
86.
87.
88.
Associated with a finite-dimensional algebra of global dimension at most 2, a generalized cluster category was introduced in Amiot (2009) [1]. It was shown to be triangulated, and 2-Calabi–Yau when it is Hom-finite. By definition, the cluster categories of Buan et al. (2006) [4] are a special case. In this paper we show that a large class of 2-Calabi–Yau triangulated categories, including those associated with elements in Coxeter groups from Buan et al. (2009) [7], are triangle equivalent to generalized cluster categories. This was already shown for some special elements in Amiot (2009) [1]. 相似文献
89.
We study the high‐contrast biharmonic plate equation with Hsieh–Clough–Tocher discretization. We construct a preconditioner that is robust with respect to contrast size and mesh size simultaneously based on the preconditioner proposed by Aksoylu et al. (Comput. Vis. Sci. 2008; 11 :319–331). By extending the devised singular perturbation analysis from linear finite element discretization to the above discretization, we prove and numerically demonstrate the robustness of the preconditioner. Therefore, we accomplish a desirable preconditioning design goal by using the same family of preconditioners to solve the elliptic family of PDEs with varying discretizations. We also present a strategy on how to generalize the proposed preconditioner to cover high‐contrast elliptic PDEs of order 2k, k>2. Moreover, we prove a fundamental qualitative property of the solution to the high‐contrast biharmonic plate equation. Namely, the solution over the highly bending island becomes a linear polynomial asymptotically. The effectiveness of our preconditioner is largely due to the integration of this qualitative understanding of the underlying PDE into its construction. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
90.
Alexander Belyaev 《Journal of Difference Equations and Applications》2019,25(9-10):1468-1487
ABSTRACTWe consider a one-dimensional model of neural activity, given by a piecewise smooth discontinuous map. Fold bifurcations as well as border collision bifurcations are described in detail. Using the method of stochastic sensitivity functions, noise-induced phenomena, such as transitions within attractor and between attractors, and spike generation, are described. Statistical characteristics of interspike intervals depending on noise intensity are studied. 相似文献