全文获取类型
收费全文 | 21127篇 |
免费 | 1025篇 |
国内免费 | 1009篇 |
专业分类
化学 | 523篇 |
晶体学 | 6篇 |
力学 | 185篇 |
综合类 | 174篇 |
数学 | 3089篇 |
物理学 | 2828篇 |
综合类 | 16356篇 |
出版年
2024年 | 58篇 |
2023年 | 108篇 |
2022年 | 421篇 |
2021年 | 427篇 |
2020年 | 330篇 |
2019年 | 278篇 |
2018年 | 277篇 |
2017年 | 335篇 |
2016年 | 393篇 |
2015年 | 501篇 |
2014年 | 996篇 |
2013年 | 851篇 |
2012年 | 942篇 |
2011年 | 1251篇 |
2010年 | 1175篇 |
2009年 | 1241篇 |
2008年 | 1533篇 |
2007年 | 1987篇 |
2006年 | 1771篇 |
2005年 | 1584篇 |
2004年 | 1248篇 |
2003年 | 1096篇 |
2002年 | 839篇 |
2001年 | 653篇 |
2000年 | 447篇 |
1999年 | 373篇 |
1998年 | 320篇 |
1997年 | 262篇 |
1996年 | 230篇 |
1995年 | 217篇 |
1994年 | 179篇 |
1993年 | 134篇 |
1992年 | 116篇 |
1991年 | 92篇 |
1990年 | 91篇 |
1989年 | 90篇 |
1988年 | 74篇 |
1987年 | 48篇 |
1986年 | 25篇 |
1985年 | 28篇 |
1984年 | 16篇 |
1983年 | 16篇 |
1982年 | 17篇 |
1981年 | 7篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1978年 | 14篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 13 毫秒
921.
Fouzia Baghery 《随机分析与应用》2013,31(3):705-717
Abstract We study the problem of optimal control of a jump diffusion, that is, a process which is the solution of a stochastic differential equation driven by Lévy processes. It is required that the control process is adapted to a given subfiltration of the filtration generated by the underlying Lévy processes. We prove two maximum principles (one sufficient and one necessary) for this type of partial information control. The results are applied to a partial information mean-variance portfolio selection problem in finance. 相似文献
922.
Adrien Deloro 《代数通讯》2013,41(5):1981-2008
We identify the spaces of homogeneous polynomials in two variables 𝕂[Yk, XYk?1, ?, Xk] among representations of the Lie ring 𝔰𝔩2(𝕂). This amounts to constructing a compatible 𝕂-linear structure on some abstract 𝔰𝔩2(𝕂)-modules, where 𝔰𝔩2(𝕂) is viewed as a Lie ring. 相似文献
923.
Christakis A. Pallikaros 《代数通讯》2013,41(11):4839-4859
924.
E. van Wickeren 《Numerical Functional Analysis & Optimization》2013,34(1-2):147-180
The main purpose of this paper is to give a proof of quantitative resonance and condensation principles via Baire category arguments in contrast to the gliding hump method used previously. Thereby a new nonquantitative resonance principle is established which is concerned with dominated convergence in Frechet spaces, by the way yielding more detailed information on the structure of the underlying spaces. On the other hand, Baire's approach is an easy tool to develop condensation principles by considering residual sets. Finally, some typical applications concerning trigonometric Fourier partial sums may illustrate the result received. 相似文献
925.
A particular orthogonal map on a finite-dimensional real quadratic vector space (V,?Q) with a non-degenerate quadratic form Q of any signature (p,?q) is considered. It can be viewed as a correlation of the vector space that leads to a dual Clifford algebra C?(V*,?Q) of linear functionals (multiforms) acting on the universal Clifford algebra C?(V,?Q). The map results in a unique involutive automorphism and a unique involutive anti-automorphism of C?(V,?Q). The anti-involution reduces to reversion (resp. conjugation) for any Euclidean (resp. anti-Euclidean) signature. When applied to a general element of the algebra, it results in transposition of the element matrix in the left regular representation of C?(V,?Q). We also give an example for real spinor spaces. The general setting for spinor representations will be treated in part II of this work [R. Ab?amowicz and B. Fauser, On the transposition anti-involution in real Clifford algebras II: Stabilizer groups of primitive idempotents, Linear Multilinear Algebra, to appear]. 相似文献
926.
Thawat Changphas 《代数通讯》2013,41(4):1474-1479
927.
S. Elaydi 《Journal of Difference Equations and Applications》2013,19(6):563-589
We present here a unified treatment of asymptotic theory of linear difference equations. This is based on anadapted theory of discrete dichotomy. The obtained results narrow the gap between Poincarés Theorem and (the discrete analoue of) Levinson's Theorem. 相似文献
928.
Recently, van Neerven, Weis and the author, constructed a theory for stochastic integration of UMD Banach space valued processes. Here the authors use a (cylindrical) Brownian motion as an integrator. In this note we show how one can extend these results to the case where the integrator is an arbitrary real-valued continuous local martingale. We give several characterizations of integrability and prove a version of the Itô isometry, the Burkholder–Davis–Gundy inequality, the Itô formula and the martingale representation theorem. 相似文献
929.
930.