基于旋转二维发光二极管阵列的体三维显示系统

利用发光二极管 (LED)的高速发光特性 ,以旋转的二维发光二极管阵列为显示载体 ,通过时分寻址电路快速显示三维形体的二维截面序列。受调制的离散二维图像信息 ,因视觉暂留而形成深度效应 ,将被整合感知为一幅连续的三维图像。成功实现了具有 4 915 2个体像素 ,尺寸为14 4 .6mm× 110mm的柱体空间内的三维显示 ,图像具有双目视差、调节、会聚等常规视差信息 ,能提供真实的深度暗示 ,可同时从任意角度直接观察。论述了系统的显示原理及图像编码分解方法 ,分析和讨论了显示质量与体像素优化选取、起始位置显示信息的关联程度     

三个不动中心问题的一个三维解

本文对三个不动中心问题的平面解作进一步发展，通过对三个不动中心在四维空间中的定义得到三个不动中心问题的三维解．     

Time-harmonic acoustic propagation in the presence of a shear flow

This work deals with the numerical simulation, by means of a finite element method, of the time-harmonic propagation of acoustic waves in a moving fluid, using the Galbrun equation instead of the classical linearized Euler equations. This work extends a previous study in the case of a uniform flow to the case of a shear flow. The additional difficulty comes from the interaction between the propagation of acoustic waves and the convection of vortices by the fluid. We have developed a numerical method based on the regularization of the equation which takes these two phenomena into account. Since it leads to a partially full matrix, we use an iterative algorithm to solve the linear system.     

水轮机转轮内部的三维固液两相紊流计算

1引言本文利用两相流动的多流体模型和k－。－A。两相索流模型计算水轮机转轮内部的三维固液两相紊流。在索流两相流动的多流体即多连续介质模型中，离散相看成是Euler坐标中处理的拟流体。与小滑移和无泪移模型不同的是，多流体模型可以分别考虑大滑移和离散颗粒扩散，其间无直接联系，并且能够充分考虑离散相质量、动量及能量的湍流扩散山本文利用速度压力校正法之一：SIMPLEC法进行数值计算。该法最早使用在S．VPatankar和D．B．Snalding在1972年提出的SIMPLE算法中间，本文将其推广到具有交错网格的非正交贴体坐标系中计算三维…     

Study on Combined Method Based on 3-D ESPI

The finite element method (FEM),whether the calculation is accurate or not,depends closely on object boundary condition.If the three dimensional displacement of the object obtained in experiment is regarded as its boundary condition,a new method combining the results of experiment and calculation,called combined method (CM),is formed.The combined method possess advantages of experiment and calculation.It can correct calculation and improve the accuracy of FEM.Accordingly it has more practicability.In this paper,the three dimensional displacement fields of a typical beam loaded at three points are tested by using 3-D electric speckle pattern interferometry (ESPI).Using the experimental results as boundary condition the whole three-dimensional displacement fields can be calculated by FEM.The beam′s three-dimensional displacement fields obtained by FEM agree very well with those obtained by experiment.This proves that the combined method is effective and practicable.     

An axisymmetrical quasi-Kirchhoff-type shell element for large plastic deformations

Summary An axisymmetrical shell element for large plastic strains is developed. The theory is based on the multiplicative decomposition of the material deformation gradient into an elastic and a plastic part. For quasi-Kirchhoff-type axisymmetric shells this leads to a product of the elastic and plastic stretches. By introduction of logarithmic strains the decomposition becomes additive. Plastic incompressibility is fulfilled in an exact manner.Support for this work was provided by the Deutsche Forschungsgemeinschaft (DFG) under contract Wr 19/7-1. The financial aid for the first and second author is gratefully acknowledged.     

Integrable Noncommutative Equations on Quad-graphs. The Consistency Approach

We extend integrable systems on quad-graphs, such as the Hirota equation and the cross-ratio equation, to the noncommutative context, when the fields take values in an arbitrary associative algebra. We demonstrate that the three-dimensional consistency property remains valid in this case. We derive the noncommutative zero curvature representations for these systems, based on the latter property. Quantum systems with their quantum zero curvature representations are particular cases of the general noncommutative ones.     

连续调制光热辐射测量技术的三维理论模型

建立了连续调制光热辐射测量(PTR)的三维理论模型.理论值与实验结果符合良好,成功地解释了-维模型不能说明的结果.     

芯片封装焊球连接疲劳寿命预测分析--能量法和有效应变法之比较

研究了目前常用的两种芯片封装焊球连接的寿命预测方法一能量法和有效应变法。对焊球连接的材料本构关系进行了对比分析，并利用FORTRAN语言编制了相应的材料本构模型子程序，将其与有限元仿真工具ANSYS耦合，实现了将焊球连接的材料本构模型用户子程序导入到ANSYS的材料库。在此基础上模拟了三维芯片叠层球栅阵列尺寸封装的焊球结构，在热循环条件下(-40～ 125℃的工作状态，并分别利用能量法和有效应变法对焊球连接的寿命预测进行了比较分析，最后对两种方法作出了评价。