全文获取类型
收费全文 | 734篇 |
免费 | 15篇 |
国内免费 | 9篇 |
专业分类
化学 | 236篇 |
晶体学 | 2篇 |
力学 | 18篇 |
数学 | 311篇 |
物理学 | 191篇 |
出版年
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 13篇 |
2017年 | 12篇 |
2016年 | 25篇 |
2015年 | 6篇 |
2014年 | 13篇 |
2013年 | 36篇 |
2012年 | 28篇 |
2011年 | 38篇 |
2010年 | 15篇 |
2009年 | 15篇 |
2008年 | 29篇 |
2007年 | 33篇 |
2006年 | 40篇 |
2005年 | 36篇 |
2004年 | 26篇 |
2003年 | 21篇 |
2002年 | 22篇 |
2001年 | 9篇 |
2000年 | 13篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1996年 | 15篇 |
1995年 | 11篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 20篇 |
1991年 | 10篇 |
1990年 | 12篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 16篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 16篇 |
1981年 | 14篇 |
1980年 | 10篇 |
1979年 | 14篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 12篇 |
1974年 | 9篇 |
1973年 | 3篇 |
1971年 | 3篇 |
1967年 | 3篇 |
排序方式: 共有758条查询结果,搜索用时 15 毫秒
101.
A novel singular superelement (SSE) formulation has been developed to overcome the loss of accuracy encountered when applying the standard finite element schemes to two-dimensional elliptic problems possessing a singularity on the boundary arising from an abrupt change of boundary conditions or a reentrant corner. The SSE consists of an inner region over which the known analytic form of the solution in the vicinity of the singular point is utilized, and a transition region in which blending functions are used to provide a smooth transition to the usual linear or quadratic isoparametric elements used over the remainder of the domain. Solution of the finite element equations yield directly the coefficients of the asymptotic series, known as the flux/stress intensity factors in linear heat transfer or elasticity theories, respectively. Numerical examples using the SSE for the Laplace equation and for computing the stress intensity factors in the linear theory of elasticity are given, demonstrating that accurate results can be attained for a moderate computational effort. 相似文献
102.
Moshe Marcus 《Archive for Rational Mechanics and Analysis》1993,124(1):67-98
Communicated by J. M. Ball 相似文献
103.
Moshe Katz 《Israel Journal of Mathematics》1971,9(1):53-72
Let ℬ(m) be the set of all then-square (0–1) matrices containingm ones andn
2−m zeros, 0<m<n
2. The problem of finding the maximum ofs(A
2) over this set, wheres(A
2) is the sum of the entries ofA
2,A ∈ ℬ (m) is considered. This problem is solved in the particular casesm=n
2 −k
2 andm=k
2,k
2>(n
2/2).
This paper forms part of a thesis in partial fulfillment of the requirements for the degree of Doctor of Science at the Technion-Israel
Institute of Technology. The author wishes to thank Professor B. Schwarz and Dr. D. London for their help in the preparation
of this paper. 相似文献
104.
Moshe Sniedovich 《Operations Research Letters》1985,4(1):19-21
This paper presents the essentials of a method designed to solve optimization problems whose objective functions are of the form g(x)+ ψ(u(x)), where ψ is differentiable and either concave or convex. It is shown that solutions to such problems can be obtained through the solutions of the Lagrangian problem whose objective function is of the form g(x)+ λu(x). 相似文献
105.
Moshe Kaspi 《The Journal of the Operational Research Society》1991,42(2):165-168
This paper deals with the problem of determining the economic operating policy for inventory items which are manufactured jointly but packaged individually. The proposed new approach is very simple and efficient. An extensive simulation study is presented so that the results of several heuristics (based on a wide range of data, measuring the number of optimal solutions, average error and maximum error) can be compared. 相似文献
106.
Moshe Jarden 《Mathematische Annalen》1975,213(2):109-127
107.
108.
Moshe Sniedovich 《Discrete Applied Mathematics》1984,9(3):301-305
A method is introduced for the solution of minimization problems possessing objective functions of the form g(x)+?(u(x)), where ? is differentiable and concave. It is shown that a solution to such problems can be obtained through the solution of the Lagrangian problem whose objective function has the form g(x)+λu(x). 相似文献
109.
110.
We study some properties of the numerical radius of matrices with non-negative entries, and explicit ways to compute it. We also characterize positive matrices with equal spectral and numerical radii, i.e., positive spectral matrices. 相似文献