Surface reconstruction is one of key techniques in reverse engineering . based on unorganized discrete points come from finite element analysis triangular mesh on exterior surface of the aeroengine hollow turbine blade , this dissertation studied some related problems , such as scattered data preprocessing , quadrangle partition and surface reconstruction technology 曲面重构是逆向工程研究的重要内容之一，本文基于航空发动机空心涡轮叶片外表面的有限元三角网格离散点，对离散数据点的预处理、四边域划分及曲面重构技术进行了研究。
In this text , around the specification of frequency conversion machine , proceed some study , has finished some work as below primarily : this text will study the output characteristic and the output characteristic of variable frequency speed regulation system . the input characteristic include power quadrangle theory , the relation of cos ( ? ) , and f 本文围绕着变频系统的特殊性，进行了一些研究，主要完成以下的研究工作：本文对变频调速系统进行了输入特性和输出特性的研究，输入特性包括：功率四边形理论，功率因数、效率和频率三者之间的关系。
A tour to beijing rear lake area . visitors will be arranged to visit the old beijing lanes by rickshaws , hutong tour lasts for 2 hours , led by local guide , visitors will visit the typical chinese quadrangles , primary school , many famous old building , like the bell tower , where you can experience the real life of ordinary people in beijing 驱车20分钟到达北京什刹海，精彩的北京胡同游开始，游客将乘人力三轮车进入老北京胡同地区，走进普通百姓人家，体验北京人的传统生活，参观该地区著名的古建筑，参观时间2小时。
Based on the characteristics of the geological exploring data , a method for establishing data model was presented , in which the triangle network was combined with the quadrangle network . at last , the geologic maps needed for geological research were drawn through the gdi ( graphics device interface ) and the 3d visualization system model was established for stratumtous geological body . base on the achievments mentioned above , a software system was developed which can be used independently without relying on any software platform 文中首先介绍了可视化技术以及地质制图技术的发展，然后对地质构造可视化模型进行了研究，根据地质测量数据的特点，提出了三角形网和四边形网相结合的数据建模方法，最后通过图形接口绘制了地质研究所需的地质图件，构建了层状地质体三维可视化系统模型，并开发出了可以独立于任何软件平台使用的地质三维可视化软件系统。
