全文获取类型
收费全文 | 10939篇 |
免费 | 1011篇 |
国内免费 | 908篇 |
专业分类
化学 | 534篇 |
晶体学 | 25篇 |
力学 | 814篇 |
综合类 | 235篇 |
数学 | 10036篇 |
物理学 | 1214篇 |
出版年
2024年 | 15篇 |
2023年 | 102篇 |
2022年 | 123篇 |
2021年 | 201篇 |
2020年 | 252篇 |
2019年 | 286篇 |
2018年 | 284篇 |
2017年 | 342篇 |
2016年 | 325篇 |
2015年 | 228篇 |
2014年 | 438篇 |
2013年 | 929篇 |
2012年 | 467篇 |
2011年 | 502篇 |
2010年 | 460篇 |
2009年 | 632篇 |
2008年 | 587篇 |
2007年 | 687篇 |
2006年 | 598篇 |
2005年 | 562篇 |
2004年 | 471篇 |
2003年 | 427篇 |
2002年 | 510篇 |
2001年 | 438篇 |
2000年 | 430篇 |
1999年 | 373篇 |
1998年 | 349篇 |
1997年 | 317篇 |
1996年 | 232篇 |
1995年 | 183篇 |
1994年 | 164篇 |
1993年 | 118篇 |
1992年 | 101篇 |
1991年 | 90篇 |
1990年 | 92篇 |
1989年 | 59篇 |
1988年 | 44篇 |
1987年 | 39篇 |
1986年 | 52篇 |
1985年 | 49篇 |
1984年 | 49篇 |
1983年 | 26篇 |
1982年 | 47篇 |
1981年 | 33篇 |
1980年 | 26篇 |
1979年 | 29篇 |
1978年 | 28篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1959年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
杨晓光 《应用数学学报(英文版)》1997,13(4):337-341
1.IntroductionIntillspaperweanalyzetheconvergenceonmultiplicativeiterativealgorithmsfortheIninimizationofadiffcrentiablefunctiondefinedonthepositiveorthantofR".ThealgorithmissllggestedbyEggermolltl'],andisrelatedtotheEM[2](Expextation--Maximization)algoritllnlforPositronemissiontonlography[']andimagereconstructi..14].Wecollsidertheproblenl"linf(x)s.t.x20.Themultiplicativeiterativealgorithmshavethel'orlniforj=l,2,',n,withAhdeterminedthroughalinesearch.Whilelusem[5]establishedanelegantconv… 相似文献
12.
Lisa Lorentzen 《Numerical Algorithms》1995,10(1):69-111
Over the last 20 years a large number of algorithms has been published to improve the speed and domain of convergence of continued fractions. In this survey we show that these algorithms are strongly related. Actually, they essentially boil down to two main principles.We also prove some results on asymptotic expansions of tail values of limit periodic continued fractions.Dedicated to Luigi Gatteschi on his seventieth birthdayThis research was partially supported by The Norwegian Research Council and by the HMC project ROLLS, under contract CHRX-CT93-0416. 相似文献
13.
Jinchao Xu 《应用数学学报(英文版)》2002,18(2):185-200
Abstract Some new local and parallel finite element algorithms are proposed and analyzed in this paper foreigenvalue problems.With these algorithms, the solution of an eigenvalue problem on a fine grid is reduced tothe solution of an eigenvalue problem on a relatively coarse grid together with solutions of some linear algebraicsystems on fine grid by using some local and parallel procedure.A theoretical tool for analyzing these algorithmsis some local error estimate that is also obtained in this paper for finite element approximations of eigenvectorson general shape-regular grids. 相似文献
14.
M. M. Kostreva 《Journal of Optimization Theory and Applications》1989,62(1):63-76
Murty's algorithm for the linear complementarity problem is generalized to solve the optimality conditions for linear and convex quadratic programming problems with both equality and inequality constraints. An implementation is suggested which provides both efficiency and tight error control. Numerical experiments as well as field tests in various applications show favorable results.The author thanks K. G. Murty for his encouragement and helpful comments. 相似文献
15.
16.
Michel Weber 《Transactions of the American Mathematical Society》2006,358(2):911-936
We apply a majorizing measure theorem of Talagrand to obtain uniform bounds for sums of random variables satisfying increment conditions of the type considered in Gál-Koksma Theorems. We give some applications.
17.
We present a new approach to study the convergence of Newton's method in Banach spaces, which relax the conditions appearing in the usual studies. The approach is based on the bound required for the second derivative of the operator involved. An application to a nonlinear integral equation is presented. 相似文献
18.
Michael R. Caputo 《Natural Resource Modeling》1989,3(2):241-259
This paper analyzes the extent to which standard dynamic renewable resource models possess refutable implications. Both the steady state comparative static and local comparative dynamic properties of the standard model are studied. A unified framework is developed which enables one to analyze the qualitative properties of any standard renewable resource model. This is achieved by explicitly linking the local stability, steady state comparative static, and local comparative dynamic properties of the model. 相似文献
19.
20.
Kasper K. Berthelsen Jesper Møller 《Bulletin of the Brazilian Mathematical Society》2002,33(3):351-367
This primer provides a self-contained exposition of the case where spatial birth-and-death processes are used for perfect
simulation of locally stable point processes. Particularly, a simple dominating coupling from the past (CFTP) algorithm and
the CFTP algorithms introduced in [13], [14], and [5] are studied. Some empirical results for the algorithms are discussed.
Received: 30 June 2002 相似文献