1 . under the same kind of wall rock and the same condition , displacement of pipe liner is symmetry , for tunnel structure and suffered load are symmetry . as level terra stress is bigger , the maximum of displacement and the first main stress occur in tie - in of pipe liner structure , and its direction is radial and points in hole ; the direction of the third main stress is annular and its maximum occurs in top and bottom hole inner 1 、同一类围岩在同一种工况下，由于结构和荷载的对称性，管片衬砌结构的位移也表现出对称性，因水平向地应力较大，位移最大值、第一主应力的最大值发生在管片衬砌结构的接头处，方向为径向指向洞内；第三主应力的方向为环向，较大值发生在洞顶和洞底内侧。
Meanwhile , fundamental principles about electroless tin plating by reducing agent and disproportionation reaction were explained . function of every component in the bath was explained that complexing agent can effectively change the potential of copper and tin , and accelerate the beginning of replacement reaction favorably ; reducing agent can increase the rate of chemical reaction and has the effect of promoting reaction dynamics too ; antioxidant can effectively prevent sn2 + in the bath from being oxidated ; additive agent a can improve the stability of the bath ; additive agent b has such effects as refining and brightening for the tin deposits , and it enlarges the range of brightening section ; additive agent c used as leveling agent can not only make the depostis level off , but also improve the dispersive ability of the bath ; surface - active agent can solve bubble problem which gathered on the surface of the deposits , and improve the surface quality of the deposits and the bath stability 阐述了镀液中各组分的作用：络合剂能有效地改变铜、锡的电位，促使初期的置换反应顺利进行；还原剂能加快化学反应速度，对反应动力学有积极的促进作用；抗氧化剂能有效地防止镀液中sn ~ ( 2 + )的氧化；添加剂a能提高镀液的稳定性，添加剂b对镀层能有细化和光亮作用，扩大了镀层光亮区的范围；添加剂c作为平滑剂，不仅能增强镀层表面的平整性，而且能提高镀液的分散能力；表面活性剂较好地解决了化学镀过程中汽泡在镀件表面聚集的问题，提高了镀层的表面质量和镀液的稳定性。
For the purpose of battlefield terrain simulation , in order to solve the problem of building and real - time display of large scale terrain , designed and developed a 3d terrain model database of missile force virtual training , optimized the model with its key technology , such as levels of detail , texture mapping etc , and proposed a solution for real - time display of large scale terrain based on view - point and double measurement which has been successfully applied into the simulation training of missile force 摘要以战场地形仿真为目的，针对某导弹阵地大规模地形生成与实时显示问题，设计开发了适用于某导弹部队虚拟训练的三维地形模型数据库，采用层次细节、纹理映射等关键技术对模型进行优化处理，提出基于视点的双度量法实时显示大规模地形，将将其成功应用于某导弹部队虚拟训练中。
From the viewpoint of real - time display and control , series of model - simplified method is applied , such as level of detail degree of freedonu instance etc . as a special problem in the modeling of seaport container logistics system , the modeling method of flexible object is presented . chapter eight gives the framework of oopn - based simulation of seaport container logistics system , which includes oopn - based digital simulation of the system and virtual reality - based simulation of the system 第八章以第四章和第七章的工作为基础，首先提出了基于oopn模型的港口集装箱物流系统虚拟现实仿真的体系结构，该体系中主要包括基于00pn模型的系统数字仿真和基于虚拟场景模型的三维实时动态仿真两部分，最后给出上海龙吴港集装箱码头仿真运行实例。
Of course as level of health of the whole people rise , the mean life of people will rise somewhat , but can not need to defer emeritus age consequently formerly because of this , because emeritus age still has other factors , especially such chinese population is large country , element of gradient of social obtain employment is far many more important than this 当然随着全民健康水平的提高，人们的平均寿命将有所提高，但并不能因为这个原因而需要推迟退休年龄，因为退休年龄还有其他的因素，非凡是中国这样的人口大国，社会就业梯度因素远比这重要的多。
Level set is a strong robust algorithm about curves ’ evolution by taking the evolving curves as level set in the higher dimensions , utilizing the computing approach based on hyperbolic conversation law , and applying the similarity between of curves evolution and hamiton - jacobi equations Levelset方法的基本数学思想是将当前正在演化的曲线看作是一个更高维函数的水平集,借用双曲守恒定律的计算方法,利用曲线演化与hamilton - jacobi方程的相似性,给出了一种曲线演化的强鲁棒性的计算方法。
