首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1232篇
  免费   97篇
  国内免费   65篇
化学   30篇
力学   195篇
综合类   11篇
数学   756篇
物理学   402篇
  2024年   3篇
  2023年   8篇
  2022年   10篇
  2021年   23篇
  2020年   30篇
  2019年   26篇
  2018年   21篇
  2017年   35篇
  2016年   33篇
  2015年   34篇
  2014年   57篇
  2013年   108篇
  2012年   54篇
  2011年   70篇
  2010年   64篇
  2009年   91篇
  2008年   96篇
  2007年   87篇
  2006年   70篇
  2005年   51篇
  2004年   47篇
  2003年   58篇
  2002年   32篇
  2001年   42篇
  2000年   32篇
  1999年   34篇
  1998年   34篇
  1997年   24篇
  1996年   13篇
  1995年   11篇
  1994年   11篇
  1993年   11篇
  1992年   9篇
  1991年   4篇
  1990年   4篇
  1989年   2篇
  1988年   7篇
  1987年   7篇
  1986年   4篇
  1985年   4篇
  1984年   4篇
  1983年   3篇
  1981年   6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
  1957年   1篇
排序方式: 共有1394条查询结果,搜索用时 15 毫秒
961.
本文通过积分检验, 刻画了不同分布的$\varphi$-混合序列后置和的极限结果,并由此导出了它们的Chover型重对数律,推广和改进了已有的结果.  相似文献   
962.
Strong laws of large numbers (SLLN) for weighted averages are proved under various dependence assumptions when the variables are not necessarily independent or identically distributed. The results considerably extend the existing results. Weighted versions of the Marcinkiewicz-Zygmund SLLN are also formulated and proved under a similar set up. It seems that such results are not known even for independent and identically distributed random variables.  相似文献   
963.
Conservation laws for nonlinear telegraph equations   总被引:2,自引:0,他引:2  
A complete conservation law classification is given for nonlinear telegraph (NLT) systems with respect to multipliers that are functions of independent and dependent variables. It turns out that a very large class of NLT systems admits four nontrivial local conservation laws. The results of this work are summarized in tables which display all multipliers, fluxes and densities for the corresponding conservation laws. A physical example is considered for possible applications.  相似文献   
964.
IntroductionIn recent decades much attention has been paid to the study of the long time behaviour ofs。table classes of solutions of partial mfferentlal equatlo。。lug the concrpts of dynamicalsystems  相似文献   
965.
For each irrational a, 0<a<1, a particular countable graph G is defined which mirrors the asymptotic behavior of the random graph G(n, p) with edge probability p = n?a.  相似文献   
966.
李子平 《中国物理 C》2002,26(12):1214-1222
基于高阶微商奇异拉氏量系统的相空间生成泛函,导出了定域和非定域变换下的量子正则Noether恒等式;对高阶微商规范不变系统,导出了位形空间中定域和非定域变换下的量子Noether恒等式.指出在某些情形下,由量子Noether恒等式可导致系统的量子守恒律.这种求守恒律的程式与量子Noether(第一)定理不同.用于高阶微商非AbelChern-Simons(CS)理论,求出某些非定域等变换下的量子守恒量.  相似文献   
967.
In this paper, we developed a class of the fourth order accurate finite volume Hermite weighted essentially non-oscillatory (HWENO) schemes based on the work (Computers & Fluids, 34: 642–663 (2005)) by Qiu and Shu, with Total Variation Diminishing Runge-Kutta time discretization method for the two-dimensional hyperbolic conservation laws. The key idea of HWENO is to evolve both with the solution and its derivative, which allows for using Hermite interpolation in the reconstruction phase, resulting in a more compact stencil at the expense of the additional work. The main difference between this work and the formal one is the procedure to reconstruct the derivative terms. Comparing with the original HWENO schemes of Qiu and Shu, one major advantage of new HWENO schemes is its robust in computation of problem with strong shocks. Extensive numerical experiments are performed to illustrate the capability of the method. Corresponding author This work was partially supported by the National Natural Science Foundation of China (Grant No. 10671097), the European project ADIGMA on the development of innovative solution algorithms for aerodynamic simulations, Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry and the Natural Science Foundation of Jiangsu Province (Grant No. BK2006511)  相似文献   
968.
在本文中, 我们提出了一类直接描述多只股票收益率受股票本身的量价影响及其它股票的量价影响下的非线性统计模型. 我们证明了在不同的参数取值下, 收益率序列分别依分布收敛于L\'evy指数稳定分布和L\'evy稳定分布.  相似文献   
969.
In fuzzy logic, connectives have a meaning that, can frequently be known through the use of these connectives in a given context. This implies that there is not a universal-class for each type of connective, and because of that several continuous t-norms, continuous t-conorms and strong negations, are employed to represent, respectively, the and, the or, and the not. The same happens with the case of the connective If/then for which there is a multiplicity of models called T-conditionals or implications. To reinforce that there is not a universal-class for this connective, four very simple classical laws translated into fuzzy logic are studied.  相似文献   
970.
刘法贵  张愿章 《数学季刊》2007,22(1):143-154
In this paper,we investigate the relaxation phenomenon for quasilinear hyper- bolic conservation laws,and obtain global smooth solutions and the life span of classical solutions to its Canchy problem.These results shows that the relaxation admits the effects of dissipation.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号