全文获取类型
收费全文 | 11899篇 |
免费 | 694篇 |
国内免费 | 971篇 |
专业分类
化学 | 1191篇 |
晶体学 | 14篇 |
力学 | 688篇 |
综合类 | 119篇 |
数学 | 9438篇 |
物理学 | 2114篇 |
出版年
2023年 | 111篇 |
2022年 | 149篇 |
2021年 | 187篇 |
2020年 | 231篇 |
2019年 | 248篇 |
2018年 | 261篇 |
2017年 | 284篇 |
2016年 | 343篇 |
2015年 | 223篇 |
2014年 | 439篇 |
2013年 | 907篇 |
2012年 | 491篇 |
2011年 | 543篇 |
2010年 | 507篇 |
2009年 | 727篇 |
2008年 | 835篇 |
2007年 | 783篇 |
2006年 | 702篇 |
2005年 | 622篇 |
2004年 | 460篇 |
2003年 | 558篇 |
2002年 | 502篇 |
2001年 | 375篇 |
2000年 | 367篇 |
1999年 | 375篇 |
1998年 | 327篇 |
1997年 | 332篇 |
1996年 | 196篇 |
1995年 | 171篇 |
1994年 | 142篇 |
1993年 | 108篇 |
1992年 | 86篇 |
1991年 | 82篇 |
1990年 | 90篇 |
1989年 | 69篇 |
1988年 | 83篇 |
1987年 | 61篇 |
1986年 | 53篇 |
1985年 | 74篇 |
1984年 | 70篇 |
1983年 | 27篇 |
1982年 | 54篇 |
1981年 | 41篇 |
1980年 | 39篇 |
1979年 | 30篇 |
1978年 | 36篇 |
1977年 | 42篇 |
1976年 | 32篇 |
1974年 | 19篇 |
1973年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
Mira Bozzini Licia Lenarduzzi Robert Schaback 《Advances in Computational Mathematics》2002,16(4):375-387
We present an adaptive method to extract shape-preserving information from a univariate data sample. The behavior of the signal is obtained by interpolating at adaptively selected few data points by a linear combination of multiquadrics with variable scaling parameters. On the theoretical side, we give a sufficient condition for existence of the scaled multiquadric interpolant. On the practical side, we give various examples to show the applicability of the method. 相似文献
72.
P. Recht 《Mathematical Methods of Operations Research》1992,36(3):201-210
In this paper we present a concept of the construction of generalized gradients by considering a development of directional derivatives into spherical harmonics. This leads to a derivation system as a system of generalized partial derivatives. Necessary conditions for local extrema for a broad class of not necessarily differentiable function can be given and a characterization of points of differentiability can be proved by using generalized gradients. 相似文献
73.
S Ponnusamy 《Proceedings Mathematical Sciences》1994,104(2):397-411
Denote byS
* (⌕), (0≤⌕<1), the family consisting of functionsf(z)=z+a
2z2+...+anzn+... that are analytic and starlike of order ⌕, in the unit disc ⋎z⋎<1. In the present article among other things, with very
simple conditions on μ, ⌕ andh(z) we prove the f’(z) (f(z)/z)μ−1<h(z) implies f∈S*(⌕). Our results in this direction then admit new applications in the study of univalent functions. In many cases these results
considerably extend the earlier works of Miller and Mocanu [6] and others. 相似文献
74.
This paper presents an algorithm and the supporting theory for solving a class of nonlinear multiple criteria optimization problems using Zionts—Wallenius type of interaction. The Zionts—Wallenius method, as extended in this paper, can be used for solving multiple criteria problems with concave objective and (implicit) value functions and convex feasible regions. Modifications of the method to handle nonconvex feasible regions and general nonlinear objective functions are also discussed.This research was supported, in part, by a Faculty Research Development Award and by a Council of 100 Research Grant from Arizona State University (Roy), and by a grant from Y. Jahnsson Foundation, Finland (Wallenius). The research was performed while the second author was a Visiting Professor at Arizona State University. 相似文献
75.
76.
B.J. Stoyanov R.A. Farrell J.F. Bird 《Journal of Computational and Applied Mathematics》1994,50(1-3):533-543
Asymptotic expansions of certain finite and infinite integrals involving products of two Bessel functions of the first kind are obtained by using the generalized hypergeometric and Meijer functions. The Bessel functions involved are of arbitrary (generally different) orders, but of the same argument containing a parameter which tends to infinity. These types of integrals arise in various contexts, including wave scattering and crystallography, and are of general mathematical interest being related to the Riemann—Liouville and Hankel integrals. The results complete the asymptotic expansions derived previously by two different methods — a straightforward approach and the Mellin-transform technique. These asymptotic expansions supply practical algorithms for computing the integrals. The leading terms explicitly provide valuable analytical insight into the high-frequency behavior of the solutions to the wave-scattering problems. 相似文献
77.
Invex-convexlike functions and duality 总被引:4,自引:0,他引:4
P. Q. Khanh 《Journal of Optimization Theory and Applications》1995,87(1):141-165
We define a class of invex-convexlike functions, which contains all convex, pseudoconvex, invex, and convexlike functions, and prove that the Kuhn-Tucker sufficient optimality condition and the Wolfe duality hold for problems involving such functions. Applications in control theory are given.The author is grateful to Professor W. Stadler and the referees for many valuable remarks and suggestions, which have enabled him to improve considerably the paper. 相似文献
78.
青岛港货运吞吐量的时间序列模型 总被引:2,自引:0,他引:2
运用时间序列分析方法对时间序列建立ARMA,ARIMA模型.搜集了青岛港1999年1月~2003年5月的货运吞吐量数据,对进行分析,建立了青岛港货运吞吐量的模型.通过预留的部分数据对模型进行检验,并对模型的残差进行检验,得出模型比较合理. 相似文献
79.
Josef Obermaier 《Journal of Approximation Theory》2003,125(2):303-312
Let
be compact with #S=∞ and let C(S) be the set of all real continuous functions on S. We ask for an algebraic polynomial sequence (Pn)n=0∞ with deg Pn=n such that every fC(S) has a unique representation f=∑i=0∞ αiPi and call such a basis Faber basis. In the special case of
, 0<q<1, we prove the existence of such a basis. A special orthonormal Faber basis is given by the so-called little q-Legendre polynomials. Moreover, these polynomials state an example with A(Sq)≠U(Sq)=C(Sq), where A(Sq) is the so-called Wiener algebra and U(Sq) is the set of all fC(Sq) which are uniquely represented by its Fourier series. 相似文献
80.
Luiza Amália Moraes Luis Romero Grados 《Journal of Mathematical Analysis and Applications》2003,281(2):575-586
Let Au(BG) be the Banach algebra of all complex valued functions defined on the closed unit ball BG of a complex Banach space G which are uniformly continuous on BG and holomorphic in the interior of BG, endowed with the sup norm. A characterization of the boundaries for Au(BG) is given in case G belongs to a class of Banach spaces that includes the pre-dual of a Lorentz sequence space studied by Gowers in Israel J. Math. 69 (1990) 129-151. The non-existence of the Shilov boundary for Au(BG) is also proved. 相似文献