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51.
吴昭君 《数学物理学报(B辑英文版)》2014,(2):380-386
The author proves that if f : C→Cn is a transcendental vector valued meromorphic function of finite order and assume Σa∈Cn ∪{∞}δ(a) = 2, then,where .This result extends the related results for meromorphic function by Singh and Kulkarni. 相似文献
52.
《Applied Mathematical Modelling》2014,38(7-8):2130-2140
Vibration of non-uniform beams with different boundary conditions subjected to a moving mass is investigated. The beam is modeled using Euler–Bernoulli beam theory. Applying the method of eigenfunction expansion, equation of motion has been transformed into a number of coupled linear time-varying ordinary differential equations. In non-uniform beams, the exact vibration functions do not exist and in order to solve these equations using eigenfunction expansion method, an adequate set of functions must be selected as the assumed vibration modes. A set of polynomial functions called as beam characteristic polynomials, which is constructed by considering beam boundary conditions, have been used along with the vibration functions of the equivalent uniform beam with similar boundary conditions, as the assumed vibration functions. Orthogonal polynomials which are generated by utilizing a Gram–Schmidt process are also used, and results of their application show no advantage over the set of simple non-orthogonal polynomials. In the numerical examples, both natural frequencies and forced vibration of three different non-uniform beams with different shapes and boundary conditions are scrutinized. 相似文献
53.
In this paper, the singular second order differential operators are considered defined on the multi-interval. Some boundary and transmission conditions are imposed on the maximal domain functions with the spectral parameter. After constructing the differential operators associated with the boundary value transmission problems on the suitable Hilbert spaces, it is proved that these operators are the maximal dissipative operators. Finally constructing the model operators which are established with the help of the scattering functions, it is proved that all root vectors of the maximal dissipative operators are complete in the Hilbert spaces. 相似文献
54.
研究了5种α,α‘-二氧代烯酮环二硫代缩酮类化合物的碳基、碳碳双键、碳硫等一些特征红外光谱,尤其着重研究了共轭体系下的各种特征谱带随化学结构而变化的规律。 相似文献
55.
For a general class of finite element spaces based on local polynomial spaces E with Pp⊂E⊂Qp we construct a vertex-edge-cell and point-value oriented interpolation operators that fulfil anisotropic interpolation error estimates.Using these estimates we prove ε-uniform convergence of order p for the Galerkin FEM and the LPSFEM for a singularly perturbed convection-diffusion problem with characteristic boundary layers. 相似文献
56.
Michael Thompson 《Trends in analytical chemistry : TRAC》2011,30(7):1168
Analytical chemists can advantageously use an uncertainty function to describe the performance of an analytical system in terms of the standard uncertainty or standard deviation as a function of the concentration of the analyte. This “characteristic function” is useful for estimating uncertainty at a new concentration. A similar function can be used to prescribe the uncertainty that is regarded as fit for purpose for a particular application. This “fitness function” is useful in setting standards of accuracy in proficiency tests and similar exercises without revealing the concentration of the analyte. In combination, these two functions provide a rational basis for method selection. 相似文献
57.
Wen-Rong Dai 《Journal of Mathematical Analysis and Applications》2007,327(1):188-202
In this paper, we study the regularity of the eigenvalues and eigenvectors and the existence of normalized coordinates for quasilinear hyperbolic systems with characteristic fields of constant multiplicity. We prove that the eigenvalues and eigenvectors of the system have the same regularity as the coefficients of the system. On the other hand, we show that, for the quasilinear hyperbolic system of conservation laws with characteristic fields of constant multiplicity, the normalized coordinates exist on the domain under consideration. 相似文献
58.
工程场地与城市在空间尺度上相去甚远 ,但工程场地所具备的与环境行为相近的共性 ,使其属性分析可以推广应用到城市建设所面对的整个工程地质环境。从这一意义上说 ,工程场地是整个城市宏观工程地质环境的微观单元 ,众多微观单元的组合构成了环境的宏观总体。为此 ,工程场地的三大属性———特性、适宜性、稳定性 ,可以作为城市工程地质环境分析中分析方法的基础。从工程场地分析推广到城市工程地质环境分析 ,还将有助于保证城市工程地质环境分析的定量化水平。 相似文献
59.
Hilbert空间中最终范数连续半群的特征条件 总被引:5,自引:0,他引:5
本文给出了Hilbert空间中当t>t0(t0≥0)时,按一致算子拓扑连续C0半 群T(t)的四个特征条件. 相似文献
60.