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31.
Differential algebraic equations with after-effect 总被引:4,自引:0,他引:4
C. T. H. Baker C. A. H. Paul H. Tian 《Journal of Computational and Applied Mathematics》2002,140(1-2):63-80
In this paper, we are concerned with the solution of delay differential algebraic equations. These are differential algebraic equations with after-effect, or constrained delay differential equations. The general semi-explicit form of the problem consists of a set of delay differential equations combined with a set of constraints that may involve retarded arguments. Even simply stated problems of this type can give rise to difficult analytical and numerical problems. The more tractable examples can be shown to be equivalent to systems of delay or neutral delay differential equations. Our purpose is to highlight some of the complexities and obstacles that can arise when solving these problems, and to indicate problems that require further research. 相似文献
32.
乳胶厚度对卤化银反射全息图衍射特性的影响 总被引:1,自引:0,他引:1
实验研究了自制的超细颗粒卤化银乳剂SDUF-1分别在AAC显影、改进的R-10漂白处理及改进的GP-8溶解物理显影处理条件下,其乳胶厚度对反射全息图衍射特性的影响。实验结果表明,在这两种不同处理条件下衍射效率与胶厚的关系有相当大的差别,合适的乳胶厚度分别为12μm和6μm左右。 相似文献
33.
Yongge Tian 《Journal of Mathematical Analysis and Applications》2002,266(2):333-341
We present an alternative expression for the parallel sum of k Hermitian nonnegative definite matrices by using the Moore-Penrose inverse of a block matrix. 相似文献
34.
Wang Jingxiu Zhang Jun Deng Yuanyong Li Jingqun Tian Lirong Yang Xiulan 《中国科学A辑(英文版)》2002,45(1):57-64
Based on the studies on the source regions of a group of coronal mass ejections, we have identified two types of large-scale magnetic structures, and suggested that they are intrinsic components of solar magnetism, their destabilization, expansion, and eruption into the interplanetary space are the basic physical processes which lead to the coronal mass ejections. These two types of large-scale structures are giant magnetic loops connecting the two active belts on the opposite hemispheres of the Sun, and the giant filaments (filament channels) and their related magnetic structures. The latter often appear as two parallel rows of sunspots and plage fields, which align side by side in the full disk daily and synoptic magnetograms. The magnetic neutral lines of these large-scale structures are usually longer than 50 heliographic degrees. We name this type of structure “super A configuration”. Sometimes, they are shown as very long filaments and related large-scale magnetic fields. As these magnetic structures are of very large scale, they extend to a great altitude into the corona, they are not easily recognized in magnetic field observations which are usually aimed at solar flare studies. To identify these large-scale structures becomes a key to understanding and predicting coronal mass ejections. 相似文献
35.
A graph G is 3‐domination critical if its domination number γ is 3 and the addition of any edge decreases γ by 1. Let G be a 3‐connected 3‐domination critical graph of order n. In this paper, we show that there is a path of length at least n?2 between any two distinct vertices in G and the lower bound is sharp. © 2002 John Wiley & Sons, Inc. J Graph Theory 39: 76–85, 2002 相似文献
36.
扰动周期KdV方程的小波基分析 总被引:2,自引:2,他引:0
本文利用样条小波基构造近似惯性流形来研究扰动周期KdV方程的长期动力学行为· 相似文献
37.
1引言 2006年3月 高等学校计算数学学报 设f(x)为卜1,1}上的连续函数,则以第二类Chebyshev多项式认(x)(Un(eoso)= 烈共坐)的全部零点{ 乙工工1口 式为 其中 k x无=Cos了一下丁7r 了L十1 犷_,为插值结点组的了的Gr如wald插值多项 G。(,,x)=艺了(x、)‘孟(x), n. 11 一一 k 相似文献
38.
Yan Shun MA Qing Hua MENG Hong Yu SHI Yuan De LONG Tian Bao HUANG 《中国化学快报》2006,17(6):807-808
Dencichine (β-N-oxalyl-L-α, β-diaminopropionic acid, L-ODAP), a nonprotein amino acid, is a haemostatic agent present in important Chinese medicinal herbs such as Panax notoginseng, as well as other Panax species1. It was first isolated from the seeds … 相似文献
39.
YBa2Cu3O7-δ and Tl2Ba2CaCu2O8 thin films for microwave filters were synthesized by pulsed laser deposition and the two-step thalliation process. Substrate
quality requirements and the relation of thin film morphology, microstructure with microwave surface resistance were discussed. 相似文献
40.
Using existing methods, the computation of performance-related reliability (PRR) of large-scale gracefully degrading systems is very tedious and time consuming. In this paper, the behaviour of such systems is respectively modeled as two types of diffusion processes according to their reconfiguration coverage. If the coverage is 1 (i.e. the reconfiguration is always successful), it is modeled as a regular diffusion. If, on the other hand, the coverage is less than one, it is modeled as diffusion with killing. Kolmogorov backward equations for regular diffusion processes and for diffusions with killing are then applied to compute the PRR. The methods have been applied in several examples, and the results satisfactorily agree with the accurate results. 相似文献