全文获取类型
收费全文 | 1376篇 |
免费 | 102篇 |
国内免费 | 72篇 |
专业分类
化学 | 48篇 |
力学 | 224篇 |
综合类 | 12篇 |
数学 | 838篇 |
物理学 | 428篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 9篇 |
2021年 | 22篇 |
2020年 | 33篇 |
2019年 | 29篇 |
2018年 | 26篇 |
2017年 | 39篇 |
2016年 | 37篇 |
2015年 | 40篇 |
2014年 | 66篇 |
2013年 | 119篇 |
2012年 | 63篇 |
2011年 | 84篇 |
2010年 | 78篇 |
2009年 | 98篇 |
2008年 | 101篇 |
2007年 | 97篇 |
2006年 | 78篇 |
2005年 | 55篇 |
2004年 | 51篇 |
2003年 | 70篇 |
2002年 | 32篇 |
2001年 | 46篇 |
2000年 | 33篇 |
1999年 | 38篇 |
1998年 | 33篇 |
1997年 | 26篇 |
1996年 | 17篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1993年 | 12篇 |
1992年 | 11篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 9篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 7篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有1550条查询结果,搜索用时 15 毫秒
1.
2.
The purpose of this article is to investigate high‐order numerical approximations of scalar conservation laws with nonlocal viscous term. The viscous term is given in the form of convolution in space variable. With the help of the characteristic of viscous term, we design a semidiscrete local discontinuous Galerkin (LDG) method to solve the nonlocal model. We prove stability and convergence of semidiscrete LDG method in L2 norm. The theoretical analysis reveals that the present numerical scheme is stable with optimal convergence order for the linear case, and it is stable with sub‐optimal convergence order for nonlinear case. To demonstrate the validity and accuracy of our scheme, we test the Burgers equation with two typical nonlocal fractional viscous terms. The numerical results show the convergence order accuracy in space for both linear and nonlinear cases. Some numerical simulations are provided to show the robustness and effectiveness of the present numerical scheme. 相似文献
3.
A new third‐order WENO scheme is proposed to achieve the desired order of convergence at the critical points for scalar hyperbolic equations. A new reference smoothness indicator is introduced, which satisfies the sufficient condition on the weights for the third‐order convergence. Following the truncation error analysis, we have shown that the proposed scheme achieves the desired order accurate for smooth solutions with arbitrary number of vanishing derivatives if the parameter ε satisfies certain conditions. We have made a comparative study of the proposed scheme with the existing schemes such as WENO‐JS, WENO‐Z, and WENO‐N3 through different numerical examples. The result shows that the proposed scheme (WENO‐MN3) achieves better performance than these schemes. 相似文献
4.
In structural dynamics, similitude laws usually deal with simple configurations as thin flat plates with point forces. Only recently, few papers have analyzed stiffened shells or stochastic pressure loads.This research activity extends the applicability of some similitude laws, developed for thin flat plates under a turbulent boundary layer load, to ribbed plates forced by the same wall pressure fluctuations.The work addresses the problem of designing a scaled experimental test-article and, successively, of re-modulating the measured data in order to get the structural response of an original (unscaled) configuration.Due to the complexity of the structural domain, the design of a scaled configuration leads to a distorted similitude. Then, a simple approach, to circumvent the distortion effects, is proposed. 相似文献
5.
《Physics letters. A》2020,384(31):126814
This paper reveals soliton solutions to magneto–optic waveguides that maintain parabolic–nonlocal law of refractive index. The unified Riccati equation expansion together with extended auxiliary equation approach together reveal bright, dark, singular as well as straddled optical solitons. These soliton solutions are obtained through a limiting process when the modulus of ellipticity approaches unity. Finally, the conservation laws are also listed. 相似文献
6.
7.
8.
Victor Oxman Moshe Stupel 《International Journal of Mathematical Education in Science & Technology》2018,49(3):442-455
A geometrical task is presented with multiple solutions using different methods, in order to show the connection between various branches of mathematics and to highlight the importance of providing the students with an extensive ‘mathematical toolbox’. Investigation of the property that appears in the task was carried out using a computerized tool. 相似文献
9.
10.