管

Firstly, a computational formula of RS which used widely in pipelines design is introduced. Secondly, a correction formula is deduced based on Spangler model. Thirdly, a model of buried pipelines is analyzed with finite element program. After compared with different results, it is found that the result from the correction formula matches with the result of FE better than that of the design code.

以现行的管道结构设计规范为例介绍了目前管道工程设计中常用的管土相对刚度计算公式，在Spangler管道土压力模型基础上推导了计算埋地管道管土相对刚度的修正公式，并采用有限元模型分析了上埋式管道的管土相互作用机理。

Mastery the method of root canal treatment, includeing method of root canal preparation (standardized system, step-back technique, step-down technique) and root canal condensation technique, principle , operation, incidental problem in the operation course of every kind endodontic treatment method

掌握根管治疗的操作方法，包括根管预备方法（标准法，逐步后退法，冠根向深入法）和根管充填方法，各种牙髓治疗方法的原理、适应症、操作方法及操作过程中容易发生的问题

My Premier Wen Jiabao used to say, here I quote,"I firmly believe that if the general public could run well a village, they could certainly do the same for a town, a county or even a province. However, we should take phased steps to develop our unique democracy in consistency with our own national conditions."

温家宝总理说过："我坚信，群众能管好一个村，就一定能够管好一个乡，一个县，也就能够管好一个省，但要按中国的实际情况，循序渐进地发展具有自己特色的民主方式。"

Compared with smooth tube,micro-fin tube has more geometrical parameters that influence heat transfer to different extent.Many scholars has done much work on it,but some research results are different or even contradictable.

相对于光管，微肋管的结构参数相对较多，这些结构参数的变化会不同程度地影响微肋管的换热能力，国内外的很多学者进行了研究，但结论相差较大，甚至完全相反。

Who cares or Full Moon Lau; regardless of barriers to cordon off the ice, or the Great Wall Fiberhome; Yijiang Chunshui cares, or wild geese have been sad.

管它巴山夜雨，还是西楼满月；管它冰河铁马，还是长城烽火；管它一江春水，还是雁过伤心。

Connnection type Teflon corrugate dpipe has many kinds of connection type.in general,it can use flange conn.,oil--conne.and directly connected with pipes fixed with p;ipe clip or wire.we can also produce dn4-32MM non net casing f4 fstened hos,or supply coressponding conn.from as per request of users.

聚四氟乙烯波纹管连接方式有多种。一般可用法兰连接，油任连接，螺纹连接，快速接头，以及直接与管件连接，以管卡或金属丝固定。DN4-32mm无波网套F4扣压软管均可生产，我厂亦可根据用户的要求提供相应的连接方式。

Based on the model, computational method about the critical velocity of straight tube arrays is given.

2利用本文模型，给出了直管管阵临界流速的计算方法，详细地讨论了矩形管阵和三角形管的临界流速。

Based on the model, computational method about the critical velocity of straig...

2利用本文模型，给出了直管管阵临界流速的计算方法，详细地讨论了矩形管阵和三角形管的临界流速。

Can, under the guidance of the teacher, the correct file to use root canal + protaper, prepared root canal, the sharp taper gutta-percha filling + fiber post + crown restoration or filling operation, the independent number of cases completed root canal therapy and filling.

能够在老师的指导下，正确运用根管锉＋protaper，预备根管，大锥度牙胶尖充填＋纤维桩＋冠修复或充填术，独立完成若干例根管治疗及充填术。

The thesis can be divided into five parts as follows: First, the structural characteristics of finned-pipe evaporator are analyzed. After selecting suitable microelement controller, the heat-transfer and mass-transfer processes are analyzed for every microelement under the conditions of dryness, wetness and frostiness. Based on previous equations, some parameters of frostiness are confirmed and the frost-growing model is set up under frost condition. Some hypotheses are postulated and with the help of the equation of mass-conservation, energy-conservation and momentum-conservation, the evaporation model which fits in the dynamic simulation is built, which set a solid foundation for system simulation. Second, the starting and stopping behaviors under disturbed condition are analyzed and calculated by using the dynamic concentrative parameter model, which gives some advice to better prescribe refrigeration system and set theoretic foundation for carrying out automatic control of refrigeration system. Third, the normal running process is analyzed and calculated by means of rational matching theory, which gives some advice on how to better understand the parameter change under steady state and the affection of inlet-parameter on evaporator. Fourth, the simulation software with dynamic characteristic is designed, which can be applied to calculate thernio-parameter of cryogen, air humidity and frost thickness under different initial and boundary conditions, and to carry out dynamic simulation under conditions of dryness, wetness and frostiness, at the same time, to achieve detection and simulation at any stage from starting to stopping.

本文的主要内容如下：1对翅片管蒸发器结构特点进行分析，选取适当的微元控制体，就干、湿和霜工况下对每个微元分别进行传热传质分析，基于经验关系式确定霜的有关参数，对于霜工况下的霜生长建立模型，经适当假设，运用质量守恒、能量守恒和动量守恒方程建立适合动态仿真的蒸发器数学模型，为系统仿真奠定基础； 2对蒸发在大扰动下的开、停机过程，运用动态集中参数模型进行分析和计算，为更好地描述制冷系统运行的全过程奠定基础，同时也为制冷系统实现自动控制提供一定的理论基础； 3对蒸发器正常运行过程，运用动态分布参数和参数间定量耦合的观点来分析和计算，为更好地了解稳态工况下各点参数的变化情况及各入口参数对蒸发器动态特性的影响即蒸发器性能对各参数变化的敏感性； 4编写翅片管蒸发器动态特性仿真计算程序，可以计算不同边界条件和初始条件下的制冷剂热力参数、空气温湿度和霜厚度分布场，实现对翅片管蒸发器在干、湿和霜工况下的动态仿真。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。