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91.
92.
Yao-junYe 《应用数学学报(英文版)》2004,20(1):93-100
In this paper we show the decay of solutions to the initial-boundary value problem for somenonlinear hyperbolic equation with a nonlinear dissipative term,by using a difference inequality. 相似文献
93.
Claude Ederer Matej Komelj James W. Davenport Manfred Fhnle 《Journal of Electron Spectroscopy and Related Phenomena》2003,130(1-3):97-100
The magnetic dipole term T appearing in the X-ray magnetic circular dichroism (XMCD) spin sum rule can be eliminated from the analysis within the spin sum rule by angle-dependent XMCD spectroscopy if the effects of spin–orbit coupling are small so that Tx+Ty+Tz≈0. It is shown by the ab initio electron theory for the extreme case of a low-dimensional system, i.e., for a free-standing monatomic Co wire that this relation is strongly violated, indicating that the determination of T by the angle-dependent XMCD is possibly not very reliable for low-dimensional magnetic systems. 相似文献
94.
Franciszek Hugon Szafraniec 《Numerical Algorithms》2003,33(1-4):475-483
We discuss a possibility of deciding whether measures representing a moment sequence or realizing orthogonality of polynomials have atoms. This is done on the real line and in several variables. 相似文献
95.
R. G. Vishwakarma 《General Relativity and Gravitation》2001,33(11):1973-1984
Models with a dynamic cosmological term (t) are becoming popular as they solve the cosmological constant problem in a natural way. Instead of considering any ad-hoc assumption for the variation of , we consider a particular symmetry, the contracted Ricci-collineation along the fluid flow, in Einstein's theory. We show that apart from having interesting properties, this symmetry does demand to be a function of the scale factor of the Robertson-Walker metric. In order to test the consistency of the resulting model with observations, we study the magnitude-redshift relation for the type Ia supernovae data from Perlmutter et al. The data fit the model very well and require a positive non-zero and a negative deceleration parameter. The best-fitting flat model is obtained as 0 0.5 with q
0 –0.2. 相似文献
96.
On the basis of the experimental reports, the mechanism of the second-order susceptibility (2) for the thermal/electric field poling of fused silica is analyzed, and expressions for (2) are detailedly derived and numerically calculated for the first time. By comparison the theoretical value of (2) with the experiment results, we propose that the effective (2) is created via both the interaction of the intense electric field with the third-order susceptibility (3) and the dipole orientation. The theoretical results show that, in the differently applied voltage, the dipole orientation and (3) play different role in the formation of (2). This theory successfully explains some experiment results. 相似文献
97.
具强迫力的奇数阶中立型微分方程的振动性 总被引:3,自引:0,他引:3
Abstract. In this paper, the forced odd order neutral differential equations of the form are con-sidered 相似文献
98.
99.
Anirudh Pradhan Purnima Pandey Kanti Jotania Mahesh Kumar Yadav 《International Journal of Theoretical Physics》2007,46(11):2774-2787
Plane symmetric viscous fluid cosmological models of the universe with a variable cosmological term are investigated. The
viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear
viscosity is to be proportional to rate of expansion in the model. We have also obtained a special model in which the shear
viscosity is assumed to be zero. The cosmological constant Λ is found to be a decreasing function of time and a positive which is supported by results from recent supernovae Ia observations.
Some physical and geometric properties of the models are also discussed. 相似文献
100.
《Optimization》2012,61(2):133-161
The aim of this article is to give a survey of some basic theory of semi-infinite programming. In particular, we discuss various approaches to derivations of duality, discretization, and first- and second-order optimality conditions. Some of the surveyed results are well known while others seem to be less noticed in that area of research. 相似文献