Asymptotic profiles and asymptotic distributions of energy in elastic waves scattering

We compute the asymptotic wave profiles for the exterior problemin elasticity with homogeneous Neumann condition. We give preciseresults on the asymptotic distribution of the elastic energyin various subsets of space. These results are obtained viathe use of a recently developed extension of the scatteringtheory of C. Wilcox (Mabrouk & Helali, 2002).     

Hugoniót--Maslov Conditions for Vortex Singular Solutions of the Shallow Water Equations

For the phase of vortex singular solutions of the shallow water equations we justify the Hamilton--Jacobi equation corresponding to the hydrodynamical mode of perturbation propagation. We also obtain the next correction to the Cauchy--Riemann conditions describing how the singular part of the solution affects the smooth background.     

On the Continuity of the Generalized Nemytskii Operator on Spaces of Differentiable Functions

We obtain sufficient conditions for the continuity of the general nonlinear superposition operator (generalized Nemytskii operator) acting from the space of differentiable functions on a bounded domain to the Lebesgue space . The values of operators on a function are locally determined by the values of both the function itself and all of its partial derivatives up to order inclusive. In certain particular cases, the sufficient conditions obtained are proved to be necessary as well. The results are illustrated by several examples, and an application to the theory of Sobolev spaces is also given.     

Strong duals of projective limits of (LB)-spaces

We investigate the problem when the strong dual of a projective limit of (LB)-spaces coincides with the inductive limit of the strong duals. It is well-known that the answer is affirmative for spectra of Banach spaces if the projective limit is a quasinormable Fréchet space. In that case, the spectrum satisfies a certain condition which is called strong P-type. We provide an example which shows that strong P-type in general does not imply that the strong dual of the projective limit is the inductive limit of the strong duals, but on the other hand we show that this is indeed true if one deals with projective spectra of retractive (LB)-spaces. Finally, we apply our results to a question of Grothendieck about biduals of (LF)-spaces.     

Measuring the Polarization Parameters of Rain by Inverse Scattering

The theory is presented for one method of determining the effective polarization parameters of the rain medium in the problem of polarization information processing of detecting target. The determination of the effective polarization parameters of the propagation medium is from the data of propagation measurements over a line-of-sight link. The polarization parameters the effective average value, the effective standard deviation and F the effective shape parameter of the propagation medium are obtained by means of the method of inverse scattering, showing a good agreement with the data from direct measurements.     

Study on Planar Whispering Gallery Dielectric Resonators. I. General Properties

Several basic properties of homogeneous planar Whispering Gallery dielectric resonators are investigated through a general approach. In particular the values for the minimum and maximum allowed radius, defined by irradiation and dielectric losses, respectively, are obtained in terms of the complex dielectric constant of the involved media. The same approach is employed in the analysis of the limit allowed frequencies of a fixed family of mode, leading to the definition of the ideal frequency band. The role of the transverse mode is then discussed, and the effective frequency band is introduced and determined both in simple disc and circular ring resonators. The extension of the effective band is limited at least by a factor 3, in terms of decades, in comparison to the extension of the ideal one; this limitation, due to the presence of transverse modes, can be overcome using suitable designed nonhomogeneous resonators, as discussed in a following companion paper.     

一类变系数广义KdV-Burgers方程的求解

给出了利用截断展开法求解一类具有变系数的广义KdV Burgers方程所需满足的条件,并得到了它的1个精 确解.     

Petrological implication of wagnerite-Ma5bc in the quartzofeldspathic gneiss, Larsemann Hills, East Antarctica

Mg dominantmineralsofwagnerite triplite group,i.e.(Mg,Fe,Mn)2(PO4)(F,OH),arerelativelyrare,buthavebeenfoundinawidevariety ofgeologicenvironments,includingmetamorphic rocksofallgrades[1]suchasquartz carbonateveinsof hydrothermalorigin,pegmatites,kyanite quartzite,micaschist,sillimanitegneiss,andmagnetiteores.Uptonow,wagneriteispresentmainlyasthe Ma2bcpolytype,anaccessorymineralincalcium poorrocks[2,5]inwhichapatite,ifpresent,oftenoc cursasretrograderimaroundwagnerite.Henriques[6]reportedasma…     

强烈段塞流特征参数试验研究

为了寻求强烈段塞流特征参数的变化规律,在高4 m、内径50 mm的管线中利用双平行电导探针测试了强烈段塞流的持液率信号,并用互相关法对其进行了分析,得到了强烈段塞流的液塞速度、液塞长度随气、液相折算速度及下倾管倾角的变化规律。结果表明,当气相折算速度恒定时,随着液相折算速度的增大,液塞速度、液塞长度均线性增大;当液相折算速度恒定时,随着气相折算速度的增大,液塞速度线性增大,而液塞长度呈双曲型减小;当气、液相折算速度恒定时,随着下倾管倾角的增大,液塞速度、液塞长度都稍有增大。     

从我国国情看图书馆的现状及其发展趋势

在分析我国国情和图书馆现状的基础上,论述了在21世纪,图书馆领域将是以传统图书馆为主导,部分复合图书馆和少量数字图书馆并存的发展趋势,而随着社会的进步和发展,复合图书馆将逐渐成为未来图书馆的主要形态.