全文获取类型
收费全文 | 1197篇 |
免费 | 56篇 |
国内免费 | 103篇 |
专业分类
化学 | 87篇 |
力学 | 16篇 |
综合类 | 24篇 |
数学 | 1092篇 |
物理学 | 137篇 |
出版年
2024年 | 1篇 |
2023年 | 11篇 |
2022年 | 21篇 |
2021年 | 14篇 |
2020年 | 30篇 |
2019年 | 22篇 |
2018年 | 21篇 |
2017年 | 25篇 |
2016年 | 32篇 |
2015年 | 13篇 |
2014年 | 49篇 |
2013年 | 121篇 |
2012年 | 30篇 |
2011年 | 60篇 |
2010年 | 42篇 |
2009年 | 77篇 |
2008年 | 89篇 |
2007年 | 94篇 |
2006年 | 74篇 |
2005年 | 56篇 |
2004年 | 57篇 |
2003年 | 45篇 |
2002年 | 54篇 |
2001年 | 41篇 |
2000年 | 38篇 |
1999年 | 38篇 |
1998年 | 41篇 |
1997年 | 25篇 |
1996年 | 20篇 |
1995年 | 13篇 |
1994年 | 15篇 |
1993年 | 12篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 3篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有1356条查询结果,搜索用时 15 毫秒
91.
Piergiulio Tempesta 《Journal of Mathematical Analysis and Applications》2008,341(2):1295-1310
A construction of new sequences of generalized Bernoulli polynomials of first and second kind is proposed. These sequences share with the classical Bernoulli polynomials many algebraic and number theoretical properties. A class of Euler-type polynomials is also presented. 相似文献
92.
We study a CUSUM–type monitoring scheme designed to sequentially detect changes in the regression parameter of an underlying
linear model. The test statistic used is based on recursive residuals. Main aim of this paper is to derive the limiting extreme
value distribution under the null hypothesis of structural stability. The model assumptions are flexible enough to include
rather general classes of error sequences such as augmented GARCH(1,1) processes. The result is underlined by an illustrative
simulation study.
Research partially supported by NSF grants DMS–0604670 and DMS–065242. 相似文献
93.
Gerry Myerson 《Discrete Mathematics》2009,309(13):4428-4434
We define an incongruent restricted disjoint covering system on [1,n] as a set of congruence classes such that each integer in the interval [1,n] belongs to exactly one class, and each class contains at least two members of the interval. In this paper we report some computational and structural results and present some open problems concerning such systems. 相似文献
94.
95.
N. S. Papageorgiou 《Journal of Optimization Theory and Applications》1990,65(1):171-178
In this note, we study the well-posedness of the problem of constrained minimization of an integral functional and show that global well-posedness is equivalent to pointwise well-posedness almost everywhere. Our result extends an earlier one by Zolezzi.This research was supported by NSF Grant No. DMS 88-02688. 相似文献
96.
We study two types of dynamical extensions of Lucas sequences and give elliptic solutions for them. The first type concerns a level-dependent (or discrete time-dependent) version involving commuting variables. We show that a nice solution for this system is given by elliptic numbers. The second type involves a non-commutative version of Lucas sequences which defines the non-commutative (or abstract) Fibonacci polynomials introduced by Johann Cigler. If the non-commuting variables are specialized to be elliptic-commuting variables the abstract Fibonacci polynomials become non-commutative elliptic Fibonacci polynomials. Some properties we derive for these include their explicit expansion in terms of normalized monomials and a non-commutative elliptic Euler–Cassini identity. 相似文献
97.
Florent Renac 《Journal of computational physics》2011,230(14):5739-5752
An algorithm for stabilizing linear iterative schemes is developed in this study. The recursive projection method is applied in order to stabilize divergent numerical algorithms. A criterion for selecting the divergent subspace of the iteration matrix with an approximate eigenvalue problem is introduced. The performance of the present algorithm is investigated in terms of storage requirements and CPU costs and is compared to the original Krylov criterion. Theoretical results on the divergent subspace selection accuracy are established. The method is then applied to the resolution of the linear advection–diffusion equation and to a sensitivity analysis for a turbulent transonic flow in the context of aerodynamic shape optimization. Numerical experiments demonstrate better robustness and faster convergence properties of the stabilization algorithm with the new criterion based on the approximate eigenvalue problem. This criterion requires only slight additional operations and memory which vanish in the limit of large linear systems. 相似文献
98.
We present an overview of the properties of the pseudohyperbolic metric in several real dimensions and study uniformly discrete sequences for the real unit ball in R^n. 相似文献
99.
The paper discusses recursive computation problems of the criterion functions of several least squares type parameter estimation methods for linear regression models, including the well-known recursive least squares (RLS) algorithm, the weighted RLS algorithm, the forgetting factor RLS algorithm and the finite-data-window RLS algorithm without or with a forgetting factor. The recursive computation formulas of the criterion functions are derived by using the recursive parameter estimation equations. The proposed recursive computation formulas can be extended to the estimation algorithms of the pseudo-linear regression models for equation error systems and output error systems. Finally, the simulation example is provided. 相似文献
100.