全文获取类型
收费全文 | 168篇 |
免费 | 13篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 5篇 |
综合类 | 22篇 |
化学工业 | 5篇 |
金属工艺 | 4篇 |
机械仪表 | 6篇 |
建筑科学 | 11篇 |
能源动力 | 3篇 |
轻工业 | 7篇 |
水利工程 | 2篇 |
武器工业 | 1篇 |
无线电 | 24篇 |
一般工业技术 | 47篇 |
冶金工业 | 1篇 |
原子能技术 | 3篇 |
自动化技术 | 48篇 |
出版年
2023年 | 3篇 |
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 1篇 |
2019年 | 4篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 12篇 |
2012年 | 14篇 |
2011年 | 13篇 |
2010年 | 7篇 |
2009年 | 8篇 |
2008年 | 13篇 |
2007年 | 9篇 |
2006年 | 14篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1992年 | 3篇 |
1990年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
排序方式: 共有189条查询结果,搜索用时 15 毫秒
1.
We present a fictitious domain decomposition method for the fast solution of acoustic scattering problems characterized by a partially axisymmetric sound‐hard scatterer. We apply this method to the solution of a mock‐up submarine problem, and highlight its computational advantages and intrinsic parallelism. A key component of our method is an original idea for addressing a Neumann boundary condition in the general framework of a fictitious domain method. This idea is applicable to many other linear partial differential equations besides the Helmholtz equation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
2.
In this paper, we derive a high-order compact finite difference scheme for solving the reaction–subdiffusion equation with Neumann boundary value condition. The L1 method is used to approximate the temporal Caputo derivative, and the compact difference operator is applied for spatial discretization. We prove that the compact finite difference method is unconditionally stable and convergent with order O(τ2?α+h4) in L2 norm, where τ, α, and h are the temporal step size, the order of time fractional derivative and the spatial step size, respectively. Finally, some numerical experiments are carried out to show the effectiveness of the proposed difference scheme. 相似文献
3.
Nonpolynomial quintic spline functions are used to develop a numerical algorithm for computing an approximation to the solution of a system of second order boundary value problems associated with heat transfer. We show that the approximate solutions obtained by our algorithm are better than those produced by other spline and domain decomposition methods. A comparison of our algorithm with nonpolynomial quadratic spline method is discussed with the help of two numerical examples. 相似文献
4.
构造所考虑的量子系统与辅助量子系统张量积空间中的经典态,利用经典态在辅助复合系统的偏迹运算,研究了无限维两体复合量子系统态纠缠的识别问题,得出了无限维两体复合量子系统态可分的一个必要充分条件,推广了Li Nan和Luo Shunlong的有限维复合量子系统的相关结果.对于识别无限维量子态的纠缠或可分是一个补充. 相似文献
5.
该文介绍了二维元胞自动机的典型邻域结构,对多状态二维元胞自动机的矩阵描述进行了拓展.通过对零边界条件下元胞自动机的状态转移矩阵的块矩阵的分析,得出矩阵的可逆性与元胞自动机冯诺依曼型邻域之间的联系. 相似文献
6.
Jing Li Olof B. Widlund 《International journal for numerical methods in engineering》2006,66(2):250-271
The FETI‐DP and BDDC algorithms are reformulated using Block Cholesky factorizations, an approach which can provide a useful framework for the design of domain decomposition algorithms for solving symmetric positive definite linear system of equations. Instead of introducing Lagrange multipliers to enforce the coarse level, primal continuity constraints in these algorithms, a change of variables is used such that each primal constraint corresponds to an explicit degree of freedom. With the new formulation of these algorithms, a simplified proof is provided that the spectra of a pair of FETI‐DP and BDDC algorithms, with the same set of primal constraints, are essentially the same. Numerical experiments for a two‐dimensional Laplace's equation also confirm this result. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
7.
Yong-Fu Zhang 《Inverse Problems in Science & Engineering》2016,24(9):1606-1646
In this paper, a recursion numerical technique is considered to solve the inverse heat conduction problems, with an unknown time-dependent heat source and the Neumann boundary conditions. The numerical solutions of the heat diffusion equations are constructed using the Gaussian radial basis functions. The details of algorithms in the one-dimensional and two-dimensional cases, involving the global or partial initial conditions, are proposed, respectively. The Tikhonov regularization method, with the generalized cross-validation criterion, is used to obtain more stable numerical results, since the linear systems are badly ill-conditioned. Moreover, we propose some results of the condition number estimates to a class of positive define matrices constructed by the Gaussian radial basis functions. Some numerical experiments are given to show that the presented schemes are favourably accurate and effective. 相似文献
8.
基于Neumann随机有限元法的复合材料压力容器的应力分析 总被引:3,自引:0,他引:3
利用Neumann级数展开的Monte-Carlo随机有限元法,分析了纤维缠绕壳体在内压及材料工程常数随机变化作用下的应力响应,绘出了最大应力响应分布曲线,为该类结构可靠性评估及可靠性设计提供了应力响应数字依据。 相似文献
9.
A. Sadeghirad S. Mohammadi 《International journal for numerical methods in engineering》2007,69(1):60-86
Equilibrium on line method (ELM) for imposition of Neumann boundary conditions in the finite point method (FPM) is presented. In contrary to weak‐form‐based methods, strong‐form‐based methods such as the FPM are often unstable and less accurate, especially for problems governed by partial differential equations with Neumann (derivative) boundary conditions. In this paper, a truly meshless approach for imposition of Neumann boundary conditions in the FPM is proposed and adopted for 2D elasticity analyses. In the proposed method, equilibrium on lines on the Neumann boundary conditions is satisfied as Neumann boundary condition equations. Numerical studies show that this method for imposition of Neumann boundary is simple to implement and computationally efficient and also leads to more stable and accurate results. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
10.
We investigated relationships between entanglement measures and the order parameter (nuclear polarization) in nuclear spin
systems controlled by the nuclear magnetic resonance (NMR) technique. Since spin polarization can be easily manipulated by
the NMR technique, experimentalists are presented with an opportunity to study the dynamic properties of entanglement, i.e.,
the creation and evolution of entangled states. Our approach may constitute the basis for researching the relations between
the entanglement measures and measurable parameters of order in other quantum systems.
An erratum to this article can be found at 相似文献