On vibration of hemispherical shell by using finite element method

This paper establishes the finite element equation for the spherical shell.The resonantfrequencies of the above shell under different boundary conditions are also discussed andcalculated.     

Navier solution for the elastic equilibrium problems of rectangular thin plates with variable thickness in linear and nonlinear theories

This paper discusses the elastic equilibrium problems of rectangular thin plates of varying thickness and simply supported on all four sides by linear and nonlinear theory. using the Navier method to seek an approach to the problem, and illustrates the solution with two examples. In conclusion, mention in made of scope of application and the convergency of the solution.     

架空输电线防振锤安装位置的工程计算

防振锤被广泛用于架空输电线以耗散微风振动的能量,减轻微风振动的强度,保护架空输电线免受疲劳损害。根据架空输电线微风振动的特点,建立数值计算模型,通过计算振幅比,确定防振锤安装位置,供架空输电线微风振动防振设计和施工时参考。     

Vibrations of stepped one-way thin rectangular plates subjected to in-plane tensile/compressive force in y-direction on Winkler' s foundation

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Natural frequencies of submerged piezoceramic hollow spheres

An exact 3D analysis of free vibration of a piezoceramic hollow sphere submerged in a compressible fluid is presented in this paper. A separation method is adopted to simplify the basic equations for spherically isotropic piezoelasticity. It is shown that there are two independent classes of vibration. The first one is independent of the fluid medium as well as the electric field, while the second is associated with both the fluid parameter and the piezoelectric effect. Exact frequency equations are derived and numerical results are obtained. The project supported by the National Natural Science Foundation of China (No. 19872060)     

On the Design of the Piecewise Linear Vibration Absorber

This paper explores the potential of the piecewise linearvibration absorber in a system subject to narrow band harmonic loading.Such a spring is chosen because the design of linear springs is commonknowledge among engineers. The two-degrees-of-freedom system is solvedby using the Incremental Harmonic Balance method, and response aspectssuch as stiffness crossing frequency and jump behaviour are discussed.The effects of mass, stiffness, natural frequency ratios, and stiffnesscrossing positions on the suppression zone are probed. It is shown thata hardening absorber can deliver a wider bandwidth than a linear oneover a range of frequencies. The absorber parameters needed to producegood designs have been determined and the quality of the realizedsuppression zone is discussed. Design guidelines are formulated to aidthe parameter selection process.     

Determination of the Molar Decadic Absorptivities of the Stretching Vibrations of the Hydride and Phenyl Groups on Aerosil® 300

 The hydride and phenyl groups on the silica surface were determined qualitatively and quantitatively. The calculation of the molar decadic absorptivities of the Si*H-stretching vibration band at 2293 cm⁻¹ and of the C*H-stretching vibration band at 3068 cm⁻¹ was carried out according to Lambert-Beer’s law.     

Modeling of stochastic modulated rattling system

Rattling vibration is an important noise source of gear-box. To control that noise, it is necessary to elaborate a mathematics-mechanical model on rattling gears. In this paper, a rattling system modulated by noise was investigated. Instead of performing the very tedious numerical calculation, a discrete stochastic model described by three dimensional mean mapping was established by means of the Non-Gaussian closure technique. Through the example, the chaotic stochastic behavior may be revealed. In comparison with deterministic model, the model developed in this paper is more approximate to practice and more available for acoustic investigation, so that it is suggested to be applied to modeling on rattling vibration.     

GeSe基薄膜太阳电池模拟研究

硫化亚锗(GeSe)具有合适的禁带宽度、高的吸收系数和高的载流子迁移率等优异的光电特性,且组分简单、低毒和储量丰富,特别适合作为光伏吸收材料。本文基于新型太阳电池吸收层材料GeSe构筑了结构为金属栅线/AZO/i-ZnO/CdS/GeSe/Mo/玻璃的薄膜太阳电池,分别模拟分析了缓冲层和吸收层的厚度、掺杂浓度,以及吸收层体缺陷密度对器件性能的影响。经过优化CdS缓冲层厚度和掺杂浓度以及GeSe吸收层厚度和掺杂浓度,器件获得高达27.59%的转换效率。这些结果表明GeSe基薄膜太阳电池有成为高效光伏器件的潜力。