In this dissertation , the varied characteristics of soi rib waveguide were investigated , and the calculated results as well as simulated plots in theory were presented . it was the first time that a 3d overlap integral method was used to calculate the transition loss between the rib waveguides and the slab waveguides , in which the effect of the mode distribution in rib waveguides on the coupling efficiency was taken into account 针对上述问题，本论文对soi波导的各种特性进行探讨并给出了详细的计算结果，首次用三维功率交迭积分法计算了soi波导器件中波导过渡区的损耗，这种方法考虑了脊形波导模式分布对过渡区耦合效率的影响。
Progress of the modeling of automotive exhaust catalytic converter was introduced , including the gas flow characteristics inside the converter , transport phenomena and reaction kinetics occurring in a single channel , the inter - channel heat transfer and the simulation of reaction behavior 摘要本文主要介绍汽车尾气催化转化器模型的研究进展，包括反应器内气体流动特性、单通道反应器内的传递现象和反应动力学、通道间的热传递和反应行为的模拟；并指出认识反应器内的各种特性和规律对设计汽车尾气催化转化器的必要性和意义。
The discussion is mainly focused on how to getting high compression of mpeg - 4 and the motion estimation algorithms are also discussed especially . this paper discusses the necessary of video encoding , reviews the mpeg - 4 series and some basic points such as the data structrues of video coding as a whole . then the use of traditional compression methods into the mpeg - 4 standard in detail , for example dct transform , motion estimation and compensation , and variable length coding , etc are discussed and a new motion estiomation algorithm is proposed 本论文研究了mpeg - 4视频编码标准中可以提高压缩比的各种特性，详细分析了mpeg - 4中的运动估计算法，做出了详细的试验对比，改进了一种易于实现的新三步搜索运动估计算法，用标准c语言实现了一个符合mpeg4asp语法标准的编码器和解码器，并利用microsoftdirectshow工具将其集成到一个实时视频流传输系统中，该系统具有扩展性和易移植性，为以后的基于网络的多媒体应用奠定了基础。
A detailed model of non - linear parametric excitation vibration coupling the stay cable and the girder , in which the static sag as well as the geometric non - linearity are considered , is proposed in this paper . based on several numeric examples investigated by the galerkin method composed with the integration strategy , several kinds of factors effecting stay cable parameter vibration are studied . another parameter vibration model by the axial excitation is presented and the corresponding nonlinear equations are derived 本文创新地提出了斜拉桥拉索-桥面耦合参数振动模型，推导了索-桥耦合非线性参数振动方程组，联合galerkin法及数值积分方法，对各种特性的拉索进行了数值求解，得出了影响拉索参数振动的各种因素；提出了斜拉索受轴向端激励参数振动模型，导出了模型的非线性振动方程，使用谐波平衡法得出了产生参数振动需要的最小激励幅值、共振时瞬态及稳态的振动幅值及索拉力的变化特性，并用数值积分方法对实际斜拉桥拉索进行了计算，分析了拉索阻尼对参数振动的影响。
