全文获取类型
收费全文 | 7370篇 |
免费 | 600篇 |
国内免费 | 636篇 |
专业分类
化学 | 205篇 |
晶体学 | 1篇 |
力学 | 403篇 |
综合类 | 197篇 |
数学 | 7373篇 |
物理学 | 427篇 |
出版年
2023年 | 67篇 |
2022年 | 64篇 |
2021年 | 117篇 |
2020年 | 167篇 |
2019年 | 189篇 |
2018年 | 179篇 |
2017年 | 205篇 |
2016年 | 220篇 |
2015年 | 145篇 |
2014年 | 295篇 |
2013年 | 547篇 |
2012年 | 340篇 |
2011年 | 382篇 |
2010年 | 322篇 |
2009年 | 448篇 |
2008年 | 431篇 |
2007年 | 461篇 |
2006年 | 420篇 |
2005年 | 351篇 |
2004年 | 307篇 |
2003年 | 296篇 |
2002年 | 318篇 |
2001年 | 307篇 |
2000年 | 299篇 |
1999年 | 258篇 |
1998年 | 236篇 |
1997年 | 217篇 |
1996年 | 158篇 |
1995年 | 134篇 |
1994年 | 103篇 |
1993年 | 74篇 |
1992年 | 62篇 |
1991年 | 58篇 |
1990年 | 55篇 |
1989年 | 32篇 |
1988年 | 24篇 |
1987年 | 27篇 |
1986年 | 29篇 |
1985年 | 38篇 |
1984年 | 32篇 |
1983年 | 20篇 |
1982年 | 36篇 |
1981年 | 24篇 |
1980年 | 20篇 |
1979年 | 23篇 |
1978年 | 22篇 |
1977年 | 17篇 |
1976年 | 11篇 |
1975年 | 4篇 |
1936年 | 3篇 |
排序方式: 共有8606条查询结果,搜索用时 796 毫秒
51.
52.
Extensible lattice sequences have been proposed and studied in [F.J. Hickernell, H.S. Hong, Computing multivariate normal probabilities using rank-1 lattice sequences, in: G.H. Golub, S.H. Lui, F.T. Luk, R.J. Plemmons (Eds.), Proceedings of the Workshop on Scientific Computing (Hong Kong), Singapore, Springer, Berlin, 1997, pp. 209–215; F.J. Hickernell, H.S. Hong, P. L’Ecuyer, C. Lemieux, Extensible lattice sequences for quasi-Monte Carlo quadrature, SIAM J. Sci. Comput. 22 (2001) 1117–1138; F.J. Hickernell, H.Niederreiter, The existence of good extensible rank-1 lattices, J. Complexity 19 (2003) 286–300]. For the special case of extensible Korobov sequences, parameters can be found in [F.J. Hickernell, H.S. Hong, P. L’Ecuyer, C.Lemieux, Extensible lattice sequences for quasi-Monte Carlo quadrature, SIAM J. Sci. Comput. 22 (2001) 1117–1138]. The searches made to obtain these parameters were based on quality measures that look at several projections of the lattice. Because it is often the case in practice that low-dimensional projections are very important, it is of interest to find parameters for these sequences based on measures that look more closely at these projections. In this paper, we prove the existence of “good” extensible Korobov rules with respect to a quality measure that considers two-dimensional projections. We also report results of experiments made on different problems where the newly obtained parameters compare favorably with those given in [F.J. Hickernell, H.S. Hong, P. L’Ecuyer, C. Lemieux, Extensible lattice sequences for quasi-Monte Carlo quadrature, SIAM J. Sci. Comput. 22 (2001) 1117–1138]. 相似文献
53.
K. V. Storozhuk 《Proceedings of the American Mathematical Society》2007,135(6):1861-1863
We give a short proof of a generalization of the Rolewicz theorem based on the uniform boundedness principle.
54.
牛顿弦截法预估校正迭代格式的收敛阶 总被引:2,自引:0,他引:2
研究如下形式的牛顿弦截法的预估校正(P.C.)格式:P(预估):~xk+1=xk-(xk-xk-1)f(xk)f(xk)-f(xk-1)C(校正):xk+1=xk-(~xk+1-xk)f(xk)f~(xk+1)-f(xk)证明了它的收敛阶为2.618. 相似文献
55.
In this note, we study convergence rates in the law of large numbers for independent and identically distributed random variables under sublinear expectations. We obtain a strong L^p-convergence version and a strongly quasi sure convergence version of the law of large numbers. 相似文献
56.
求解非线性方程的一个新方法 总被引:2,自引:0,他引:2
张艺 《宁波大学学报(理工版)》2002,15(3):55-57
提出了一种求解非线性方程的数值方法,此方法不需要导数的计算,其收敛阶与抛物线法相同,但计算量要比抛物线法小得多。 相似文献
57.
Jian‐guo Tang 《Mathematical Methods in the Applied Sciences》2006,29(11):1327-1338
An implicit iterative method is applied to solving linear ill‐posed problems with perturbed operators. It is proved that the optimal convergence rate can be obtained after choosing suitable number of iterations. A generalized Morozov's discrepancy principle is proposed for the problems, and then the optimal convergence rate can also be obtained by an a posteriori strategy. The convergence results show that the algorithm is a robust regularization method. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
58.
59.
Recently, molecular imaging has been rapidly developed to studyphysiological and pathological processes in vivo at the cellularand molecular levels. Among molecular imaging modalities, opticalimaging has attracted a major attention for its unique advantages.In this paper, we establish a mathematical framework for multispectralbioluminescence tomography (BLT) that allows simultaneous studiesof multiple optical reporters. We show solution existence, uniquenessand continuous dependence on data as well as the limiting behaviourswhen the regularization parameter approaches zero or when thepenalty parameter approaches infinity. Then, we propose twonumerical schemes for multispectral BLT and derive error estimatesfor the corresponding solutions. 相似文献
60.
A. A. Maleev 《Computational Mathematics and Mathematical Physics》2006,46(12):2031-2039
Stationary and nonstationary Jacobi-like iterative processes for solving systems of linear algebraic equations are examined. For a system whose coefficient matrix A is an H-matrix, it is shown that the convergence rate of any Jacobi-like process is at least as high as that of the point Jacobi method as applied to a system with 〈A〉 as the coefficient matrix, where 〈A〉 is a comparison matrix of A. 相似文献