全文获取类型
收费全文 | 133篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
化学 | 49篇 |
晶体学 | 1篇 |
力学 | 2篇 |
数学 | 31篇 |
物理学 | 55篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 4篇 |
2012年 | 8篇 |
2011年 | 7篇 |
2010年 | 11篇 |
2009年 | 9篇 |
2008年 | 8篇 |
2007年 | 8篇 |
2006年 | 11篇 |
2005年 | 5篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有138条查询结果,搜索用时 109 毫秒
81.
Cyclic reduction is an algorithm invented by G. H. Golub and R. W. Hockney in the mid 1960s for solving linear systems related
to the finite differences discretization of the Poisson equation over a rectangle. Among the algorithms of Gene Golub, it
is one of the most versatile and powerful ever created. Recently, it has been applied to solve different problems from different
applicative areas. In this paper we survey the main features of cyclic reduction, relate it to properties of analytic functions,
recall its extension to solving more general finite and infinite linear systems, and different kinds of nonlinear matrix equations,
including algebraic Riccati equations, with applications to Markov chains, queueing models and transport theory. Some new
results concerning the convergence properties of cyclic reduction and its applicability are proved under very weak assumptions.
New formulae for overcoming breakdown are provided. 相似文献
82.
A new algorithm is proposed for computing the intersection of two plane curves given in rational parametric form. It relies
on the Ehrlich–Aberth iteration complemented with some computational tools like the properties of Sylvester and Bézout matrices,
a stopping criterion based on the concept of pseudo-zero, an inclusion result and the choice of initial approximations based
on the Newton polygon. The algorithm is implemented as a Fortran 95 module. From the numerical experiments performed with
a wide set of test problems it shows a better robustness and stability with respect to the Manocha–Demmel approach based on
eigenvalue computation. In fact, the algorithm provides better approximations in terms of the relative error and performs
successfully in many critical cases where the eigenvalue computation fails. 相似文献
83.
In this paper we compute the generating function for the Euler characteristic of the Deligne-Mumford compactification of
the moduli space of smooth n-pointed genus 2 curves. The proof relies on quite elementary methods, such as the enumeration of the graphs involved in a
suitable stratification of .
Received September 8, 1998; in final form July 1, 1999 / Published online December 8, 2000 相似文献
84.
Let A = (aij) be an n × n Toeplitz matrix with bandwidth k + 1, K = r + s, that is, aij = aj−i, i, J = 1,… ,n, ai = 0 if i > s and if i < -r. We compute p(λ)= det(A - λI), as well as p(λ)/p′(λ), where p′(λ) is the first derivative of p(λ), by using O(k log k log n) arithmetic operations. Moreover, if ai are m × m matrices, so that A is a banded Toeplitz block matrix, then we compute p(λ), as well as p(λ)/p′(λ), by using O(m3k(log2 k + log n) + m2k log k log n) arithmetic operations. The algorithms can be extended to the computation of det(A − λB) and of its first derivative, where both A and B are banded Toeplitz matrices. The algorithms may be used as a basis for iterative solution of the eigenvalue problem for the matrix A and of the generalized eigenvalue problem for A and B. 相似文献
85.
C. K. Gelbke D. K. Scott M. Bini D. L. Hendrie J. L. Laville J. Mahoney M. C. Mermaz C. Olmer 《Physics letters. [Part B]》1977,70(4):415-417
Energy spectra and angular distributions for peripheral reactions induced by 16O on 208Pb at 20 MeV/A can be explained in terms of the intrinsic nucleon motion of the excited projectile, in a manner similar to the interpretation of projectile fragmentation reactions at 2.1 GeV/A. 相似文献
86.
We consider the problem of completion of a matrix with a specified lower triangular part to a unitary matrix. In this paper we obtain the necessary and sufficient conditions of existence of a unitary completion without any additional constraints and give a general formula for this completion. The paper is mainly focused on matrices with the specified lower triangular part of a special form. For such a specified part the unitary completion is a structured matrix, and we derive in this paper the formulas for its structure. Next we apply the unitary completion method to the solution of the eigenvalue problem for a class of structured matrices via structured QR iterations.
87.
88.
Massarotti V Capsoni D Bini M Azzoni CB Mozzati MC Galinetto P Chiodelli G 《The journal of physical chemistry. B》2006,110(36):17798-17805
Pure and doped Ba(6)Ti(2)Nb(8)O(30) (BTN), obtained by substituting M = Cr, Mn, or Fe on the Ti site (Ba(6)Ti(2-x) M(x)Nb(8)O(30), x = 0.06 and 0.18) and Y and Fe on the Ba and Ti sites, respectively (Ba(6-x)Y(x)Ti(2-x)Fe(x)Nb(8)O(30), x= 0.18), are synthesized. The influence of cation doping on the local structure, the cation oxidation state, and the possible defect formation able to maintain the charge neutrality are investigated by spectroscopic (electron paramagnetic resonance (EPR) and micro-Raman), structural (X-ray powder diffraction) and transport (impedance spectroscopy, thermoelectric power) measurements, in the temperature range of 300-1200 K in air and N(2) flow. Starting from the valence state of the doping ions (Fe(3+), Cr(3+), and Mn(2+)), determined by EPR, and from thermoelectric power measurements, evidencing a negative charge transport, different charge-compensating defect equilibria, based on the creation of positive electron holes or oxygen vacancies and electrons, are discussed to interpret the conductivity results. 相似文献
89.
Donato Bini Christian Cherubini Andrea Geralico Robert T. Jantzen 《General Relativity and Gravitation》2008,40(5):985-1012
Three natural classes of orthonormal frames, namely Frenet-Serret, Fermi–Walker and parallel transported frames, exist along
any timelike world line in spacetime. Their relationships are investigated for timelike circular orbits in stationary axisymmetric
spacetimes, and illustrated for black hole spacetimes.
Dedicated to Bahram Mashhoon for his 60th birthday. 相似文献
90.
M. Anelli S. Bertolucci C. Bini P. Branchini C. Curceanu G. De Zorzi A. Di Domenico B. Di Micco A. Ferrari S. Fiore P. Gauzzi S. Giovannella F. Happacher M. Iliescu M. Martini S. Miscetti F. Nguyen A. Passeri A. Prokofiev B. Sciascia F. Sirghi 《Nuclear Physics B - Proceedings Supplements》2009,173(1):353-357