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1.
本文用B-网方法确定了△_(nm)~((2))剖分上二次双周期样条函数空间的维数,给出了插值条件的几种提法,证明了解的存在唯一性. 相似文献
2.
In this study, the nonlinear dynamic responses of a string are simulated using the Cellular Automata method based on the reflection rule. In the case of nonlinear systems, the velocity of wave propagation is not constant and depends on the amplitude. A new treatment of the dynamic time step is proposed for the Cellular Automata method considering the effect of the propagation velocity. As numerical examples, first, the dynamic responses of a string with linear characteristic are simulated using the Cellular Automata method. A typical resonance curve can be obtained. Second, the dynamic responses of a string with nonlinear characteristic are simulated using the proposed method. Some characteristic types of vibration can be obtained. It is concluded that the linear and nonlinear dynamic responses of a string may be obtained by simulation using the Cellular Automata method. 相似文献
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INTERSECTION OF PRIME SUBMODULES AND DIMENSION OF MODULES 总被引:1,自引:0,他引:1
A.Azizi 《数学物理学报(B辑英文版)》2005,25(3):385-394
The aim of this paper is to study the conditions by which a P-prime submodule can be expressed as a finite intersection or union of P-prime submodules. Also corresponding to dimension and rank of modules, some equivalent conditions for a ring to be a Dedekind domain are given. 相似文献
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We investigate the viability of f(R) theories in the framework of the Palatini approach as solutions to the problem of the observed accelerated expansion of the universe. Two physically motivated popular choices for f(R) are considered,: power law, f(R) = β R
n
, and logarithmic, f(R) = α ln R. Under the Palatini approach, both Lagrangians give rise to cosmological models comprising only standard matter and undergoing a present phase of accelerated expansion. We use the Hubble diagram of type Ia Supernovae and the data on the gas mass fraction in relaxed galaxy clusters to see whether these models are able to reproduce what is observed and to constrain their parameters. It turns out that they are indeed able to fit the data with values of the Hubble constant and of the matter density parameter in agreement with some model independent estimates, but the today deceleration parameter is higher than what is measured in the concordance ΛCDM model. 相似文献
5.
Giovanna Idone 《Journal of Mathematical Analysis and Applications》2004,290(1):147-170
Hölder regularity up to the boundary of the solutions to the Dirichlet problem for second order elliptic systems with nonlinearity q>2 and with controlled growth is proved when n?q+2. 相似文献
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采用二硫化碳重结晶富勒烯混合物或二硫化碳二次抽提烟灰以提取高富勒烯(higherfulerenes,Cn,n>70)。产物经高效液相色谱分析,高富勒烯的含量从1%分别提高到4%和6%;经激光飞行时间质谱证明,产物中除含主要成分C60和C70以外,还含有C76、C78、C82、C84以及更高碳原子的富勒烯。 相似文献
8.
Summary The development of a computer-aided rapid-scanning detector for HPLC based on the linear photodiode array UV-visible spectrophotometer is described. Chomatograms monitored at up to three wavelengths, with automatic capture of spectra for eluted peaks and post-run processing of spectral data to generate log10 (A) spectra, second derivative and fourth derivative spectra, are described. Methods are reported for the analysis of forensic samples of diacetylmorphine (heroin) in the presence of the degradation products and potential contaminants caffeine, papaverine, 6-acetylcodeine, thebaine, 6-acetyl-morphine, procaine and morphine separated by HPLC. The novel use of second and higher derivative spectra for the qualitative characterisation of drugs and contaminants separated by HPLC is described.Presented at the 14th International Symposium on Chromatography London, September, 1982 相似文献
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