全文获取类型
收费全文 | 1070篇 |
免费 | 58篇 |
国内免费 | 106篇 |
专业分类
化学 | 85篇 |
力学 | 8篇 |
综合类 | 26篇 |
数学 | 998篇 |
物理学 | 117篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 18篇 |
2021年 | 15篇 |
2020年 | 28篇 |
2019年 | 23篇 |
2018年 | 21篇 |
2017年 | 23篇 |
2016年 | 34篇 |
2015年 | 12篇 |
2014年 | 46篇 |
2013年 | 100篇 |
2012年 | 28篇 |
2011年 | 52篇 |
2010年 | 36篇 |
2009年 | 71篇 |
2008年 | 84篇 |
2007年 | 84篇 |
2006年 | 70篇 |
2005年 | 56篇 |
2004年 | 50篇 |
2003年 | 43篇 |
2002年 | 53篇 |
2001年 | 41篇 |
2000年 | 38篇 |
1999年 | 36篇 |
1998年 | 33篇 |
1997年 | 18篇 |
1996年 | 14篇 |
1995年 | 11篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 4篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1970年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有1234条查询结果,搜索用时 109 毫秒
61.
Fernando Mayoral 《Proceedings of the American Mathematical Society》2001,129(1):79-82
We characterize the compactness of a subset of compact operators between Banach spaces when the domain space does not have a copy of
62.
Suthep Suantai 《Southeast Asian Bulletin of Mathematics》2000,24(2):297-303
In this paper, we give necessary and sufficient conditions for infinite matrices mapping from the Nakano vector-valued sequence space (X, p) into any BK-space, and by using this result, we obtain the matrix characterizations from (X, p) into the sequence spaces (Y), c0(Y, q), c(Y), s(Y), Er(Y), and Fr(Y), where p = (pk) and q = (qk) are bounded sequences of positive real numbers such that pk 1 for all k N, r 0, and s 1.AMS Subject Classification (2000): 46A45 相似文献
63.
The method of quasilinearization is a procedure for obtaining approximate solutions of differential equations. In this paper, this technique is applied to a differential-algebraic problem. Under some natural assumptions, monotone sequences converge quadratically to a unique solution of our problem. 相似文献
64.
We study rate of convergence in the strong law of large numbers for finite and infinite variance time series in both contexts of weak and strong dependence. 相似文献
65.
Ragheb M. Abu-Sarris 《Journal of Computational Analysis and Applications》2000,2(1):103-109
In this paper, we are concerned with the global behavior ofthe solutions of the difference equation
where
and
. Necessary and sufficient conditions for boundedness, persistence,and periodicity of all solutions will be established. The oscillatorybehavior will be investigated. 相似文献
66.
Sándor Bozóki 《Central European Journal of Operations Research》2008,16(4):345-358
The aim of the paper is to present a new global optimization method for determining all the optima of the Least Squares Method
(LSM) problem of pairwise comparison matrices. Such matrices are used, e.g., in the Analytic Hierarchy Process (AHP). Unlike
some other distance minimizing methods, LSM is usually hard to solve because of the corresponding nonlinear and non-convex
objective function. It is found that the optimization problem can be reduced to solve a system of polynomial equations. Homotopy
method is applied which is an efficient technique for solving nonlinear systems. The paper ends by two numerical example having
multiple global and local minima.
This research was supported in part by the Hungarian Scientific Research Fund, Grant No. OTKA K 60480. 相似文献
67.
Chameleon sequences are amino acid sequences found in several distinct configurations in experiment. They challenge our understanding of the link between sequence and structure, and provide insight into structural competition in proteins. Here, we study the energy landscapes for three such sequences, and interrogate how pulling and twisting forces impact the available structural ensembles. Chameleon sequences do not necessarily exhibit multiple structural ensembles on a multifunnel energy landscape when we consider them in isolation. The application of even small forces leads to drastic changes in the energy landscapes. For pulling forces, we observe transitions from helical to extended structures in a very small span of forces. For twisting forces, the picture is much more complex, and highly dependent on the magnitude and handedness of the applied force as well as the reference angle for the twist. Depending on these parameters, more complex and more simplistic energy landscapes are observed alongside more and less diverse structural ensembles. The impact of even small forces is significant, confirming their likely role in folding events. In addition, small forces exerted by the remaining scaffold of a protein may be sufficient to lead to the adoption of a specific structural ensemble by a chameleon sequence. 相似文献
68.
It is shown that the multiplier norm of a shifted Jacobi multiplier sequence can be estimated by the (same) multiplier norm
of the original sequence uniformly with respect to the shift. Muckenhoupt’s transplantation theorem for Jacobi series is used
essentially, for which also a functional analytic understanding is given in terms of the minimality of the Jacobi system in
weighted L
p
-spaces.
相似文献
69.
Ozer TALO Feyzi BASAR 《数学学报(英文版)》2008,24(7):1205-1212
Recently, the space bvp of real or complex numbers consisting of all sequences whose differences are in the space lp has been studied by Basar, Altay [Ukrainian Math. J. 55(1)(2003), 136-147], where 1 ≤ p ≤ ∞. The main purpose of the present paper is to introduce the space bvp(F) of sequences of p-bounded variation of fuzzy numbers. Moreover, it is proved that the space bvp(F) includes the space lp(F) and also shown that the spaces bvp(F) and lp(F) axe isomorphic for 1 ≤ p ≤∞. Furthermore, some inclusion relations have been given. 相似文献
70.