MICROSTRUCTURE AND FRACTAL FORMATION OF ANNEALED Ge-Au FILM AND Ge-Au/Au BILAYER FILMS

The as-deposited and annealed Ge-Au film and Ge-Au/Au bilayer films have been observed by transmission electron microscopy. The bilayer with a composition of Ge-5at%Au film is amorphous, while the Ge-22at%Au film is polycrystalline. Higher concentration of Au raises the structural heterogeneity and instability. Fractals can be observed in the Ge-5at%Au/Au bilayer samples annealed at 60-100℃. The difference of the fractal patterns generated from Ge-Au/An and a-Ge/Au films call be attributed to the higher heterogeneity and instability in Ge-Au/An bilayers.     

Quadratic kinetic equations are linear in the tensor product space

It is shown that quadratic kinetic equations are linear in the tensor product space.     

Reactive surface micropatterning by wet stamping

Hydrogel stamps are used to reactively micropattern various types of substrates. The method, called reactive wet stamping (r-WETS), is general in nature and overcomes several limitations of conventional soft-lithographic techniques. Illustrative applications of r-WETS in surface wettability modification, deposition of metallic microstructures, preparation of supports for electrostatic self-assembly, and multistep reactive patterning are discussed.     

An analysis of seismic attenuation in random porous media

The attenuation of seismic wave in rocks has been one of the interesting research topics, but till now no poroelasticity models can thoroughly explain the strong attenuation of wave in rocks. In this paper, a random porous medium model is designed to study the law of wave propagation in complex rocks based on the theory of Biot poroelasticity and the general theory of stochastic process. This model sets the density of grain, porosity, permeability and modulus of frame as random parameters in space, and only one fluid infiltrates in rocks for the sake of better simulation effect in line with real rocks in earth strata. Numerical simulations are implemented. Two different inverse quality factors of fast P-wave are obtained by different methods to assess attenuation through records of virtual detectors in wave field (One is amplitude decay method in time domain and the other is spectral ratio method in frequency domain). Comparing the attenuation results of random porous medium with those of homogeneous porous medium, we conclude that the attenuation of seismic wave of homogeneous porous medium is far weaker than that of random porous medium. In random porous media, the higher heterogeneous level is, the stronger the attenuation becomes, and when heterogeneity σ = 0.15 in simulation, the attenuation result is consistent with that by actual observation. Since the central frequency (50 Hz) of source in numerical simulation is in earthquake band, the numerical results prove that heterogeneous porous structure is one of the important factors causing strong attenuation in real stratum at intermediate and low frequency.     

交通产业链上企业工程项目成本控制的影响因素研究

一些企业以轨道交通产业为纽带形成了交通产业链,轨道交通产业链上的企业要注重对相关工程项目实施全过程中的成本控制.从产业链的视角出发,围绕财务指标、内部业务流程指标、客户指标、学习与成长能力指标这4个方面,构建了评价指标体系和成本控制指标体系.运用层次分析法和模糊综合评价法进行评价和分析,找出了影响轨道交通产业链上企业工程项目成本控制的主要因素.研究表明,有55%的人认为财务指标、内部业务流程指标、客户指标、学习与成长能力指标这4个因素对轨道交通工程项目成本控制的影响较大.     

Decomposition of Minkowski–Rådström–Hörmander Space to the Direct Sum of Symmetric and Asymmetric Subspaces

Any abstract convex cone S with a uniformity satisfying the law of cancellation can be embedded in a topological vector space $\widetilde{S}$ (Urbański, Bull Acad Pol Sci, Sér Sci Math Astron Phys 24:709–715, 1976). We introduce a notion of a cone symmetry and decompose in Theorem 2.12 a quotient vector space $\widetilde{S}$ into a topological direct sum of its symmetric subspace $\widetilde{S}_s$ and asymmetric subspace $\widetilde{S}_a$ . In Theorem 2.19 we prove a similar decomposition for a normed space $\widetilde{S}$ . In section 3 we apply decomposition to Minkowski–Rådström–Hörmander (MRH) space with three best known norms and four symmetries. In section 4 we obtain a continuous selection from a MRH space over ?² to the family of pairs of nonempty compact convex subsets of ?².