圆柱的

To assure parts' machining precision and to improve productivity, touch probe is used to inspect cylinder of parts on machining centers, thus coordinate of points on features are acquired from numerical control system by a data collecting program, and cylindricity error is calculated by computer. This method has broken the restriction of probe's macro processor that couldn't work out cylindricity error. Data saved in computer are beyond the limited memory of numerical control system, which improves operation speed.

为了保证零件加工精度和提高生产率，在数控加工中心中采用触发式零件检测测头对被加工件的圆柱面进行在机检测，并利用数据读取程序从数控系统内部提取被检测点坐标信息，在计算机内部完成圆柱度误差的计算，克服了零件检测测头自带宏程序无法对圆柱等被测特征进行误差运算的局限性；并且检测数据存储于计算机内，不再受数控系统内存小及运算速度慢的限制。

In addition, three-dimension scattering characteristics of aplane wave by a cylindrical conductor are described by applying reduced matrix.

应用平面波谱技术将高斯波束展开成平面波序列，然后利用叠加原理及圆柱导体的边界条件推导了基模高斯波束入射单个圆柱导体的二维散射场公式，应用约化矩阵描述了平面波入射单个圆柱导体的三维散射特性。

In the cylindrical worm pair with disk annular grinding wheel enveloped worm, the worm axial profile is concave profile.

圆弧面砂轮包络圆柱蜗杆传动，兼备了二次包络成形的特征和凹面齿圆柱蜗杆的特征，是一种很有特色的新型圆柱蜗杆传动。

The scattering by different shape and different media such as dielectric chiral or conduct circular cylider or elliptic cylinder are calculated and RCS curves are maped. The relation between the optimal polarization of the chiral elliptic cylinder and incident angle are maped. In accordance with the map, the information which is useful for radar target identification can be obtained.

对不同形状及参数的导体圆柱、椭圆柱，一般介质圆柱、椭圆柱，旋波媒质椭圆柱的散射特性进行了计算，给出了其RCS的变化曲线，并对极化散射矩阵进行了分析给出了旋波媒质椭柱最优极化的分布图，指出了其可提取用于目标识别的极化信息。

It is concerned with the optimal design of cylindrical shell on minimax deflection and minimal compliancy with arbitrary axisymmetrical boundary conditions and radial pressure, under the condition of the volume being constant.

研究在任意轴对称边界条件下和任意轴对称分布载荷作用下体积保持常数的圆柱壳的两类优化设计问题：极小化圆柱壳的最大挠度和极小化圆柱壳的柔度。

In this paper, based on the fundamental principle of the three-point method roundness error separation technique, the separation of cylindricity error factors and the reconstruction of the measured cylinder profile was intensively studied, and the methods of evaluating the cylindricity form error were discussed. Furthermore, the separation and reconstruction methods of the cylindricity error proposed in this paper were examined by the experiment.

本文采用三点法圆度误差分离技术的基本原理，重点研究圆柱度误差要素的分离和被测圆柱体形貌重构问题，探讨圆柱度形状误差的评定方法，并对本文所提的圆柱度误差分离及重构方法进行实验验证。

Aiming at precision measurement of cylindricity,this paper puts forward a kind of method which can sep- arate the cross- section roundness error,the radius error of different cross sections,the initial coordinates of least square centers of measured cross sections and can reconstruct the pattern of the measured cylinder,i.

本文针对圆柱度误差的精密测量，提出了一种可分离截面圆度误差、截面半径差和截面最小二乘圆心初始位置并重构出被测圆柱形貌的方法，即三点法圆柱度误差分离与重构技术。

The simulation results of the cylinder-block model were given in the article, consistent with that of Middlemen"s. It was shown that the block part could improve the uniformity of the flow distribution. The analysis of the flow field of some materials with different power-law factor in the die designed by Mckelvey was close to that of Mckelvey"s. It was shown that the flow distribution was uniform in the die that can producesheets with 1200mm in width. During the analysis the flow channel was divided into several parts to get the details about the fluid flow in each area. A conclusion was drawn after analyzing the influence of the die pressure on the flow distribution, that the higher pressure is good for the output and bad for the uniformity of the distribution. Simulation of the die applying the cylindrical main runner showed the fact that when the cylinder replaced the cone the change of uniformity was trivial. The uniformity of the non-block flow channel was so poor that the block in the proper position of the die channel was necessary. The project of the die for the wider sheet was put forth, and the analysis of the fluid flow in the die was shown.

本文模拟了圆柱管缝隙流模型的三维流动场，得到了与Middlemen结论一致的流动均匀性，并通过模拟直观地展示了采用阻尼块可以改善挤出均匀性的现象；分析了多种幂率指数的流体在Mckelvey等人设计的流道模型中的流动分布，得到了与Mckelvey的分析结果接近的压力降和流量偏差；本文建立了1200mm幅宽机头流道的三维有限元模型，并逐个分析各个区域和多个截面的流动分布状况，由此揭示了1200mm幅宽L-型机头流道内的流北京化工大学硕士学位论文动分布基本均匀，并在分析了机头压力对于挤出流动分布的影响后得出结论：较高的机头压力可以获得较大的产量，但是不利于物料均匀分布；模拟了采用圆柱管主流道时机头流道内的流动分布，得出结论：主流道由圆锥管改为圆柱管时对流动均匀性影响不大，通过设置适当的阻尼仍然可以达到挤出平衡；模拟了两端进料式圆柱管无阻尼流道的流动均匀性后得到结论：两端进料式无阻尼结构的流动均匀性较差，宽机头中仍然有必要设置阻尼块；确定宽幅机头流道的基本方案，并设计了一种宽幅防水卷材挤出机头流道的结构，通过流动模拟表明该种结构的流动均匀性较好；考察了宽幅机头对于不同厚度片材的挤出适应性，得到结论：当生产不同厚度的片材时，阻尼块高度需要调整。

For the first time, a screw pile and pile driver system for preventing flood and rushing to deal with an emergency was manufactured. The screw piles of the system is different from screw drills used to sap, and it doesn't push soils out. Analyses, including the screw pile's structural strength analysis and the screw blade's welding analysis, were done by ANSYS, which showed that the screw pile's structural strength is enough and that the distort of the screw blade is small. Testing on the screw pile and pile driver system showed that the system performed stably and could meet the need of preventing flood and rushing to deal with an emergency. A mechanics model of interaction of a screw pile and soil was built, and expressions of torque of screw pile's cylindrical part on the condition of screw pile's crew part being driven into soil fully were gained, then the relation of the torque with screw pitch and out diameter of cylinder, which shows the torque decreases with the screw pitch increasing, and that the torque increases with the out diameter of cylinder increasing, which was according with the experiments of the screw pile's being driven into soils, and thus a screw pile with the best structure was chosen. Experiments of bionic surface showed that, on the condition of certain pressure on the surface, the protruding bionic surface can not reduce adhesion and resistance and that the corrugated bionic surface can reduce adhesion and resistance. An orthogonal experiment of the corrugated bionic surface was done with the factors including the width of protrusion, the space between two protrusions, the trolley's velocity and the vertical surface pressure and with the surface frictional coefficient as the experimental target, and some inclusions were drawn that the best combination of the factors was acquired and that the width of protrusion affected the surface frictional coefficient remarkably.

研制了防汛抢险螺旋桩机系统，提高了沉桩作业效率；利用ANSYS对桩体进行整体结构强度分析以及螺旋叶片的焊接分析，表明桩体结构强度足够，焊接过程中，螺旋叶片的变形小；对整个螺旋桩机系统进行试验，表明该系统性能可靠，工作稳定，作业效率高，能够满足防汛抢险沉桩作业基本需要；建立了螺旋桩桩土作用力学模型，得出螺旋桩沉桩过程中螺旋桩螺旋部分完全进入土体时螺旋桩圆柱部分所受扭矩以及扭矩与防汛抢险螺旋桩的螺旋导程和圆柱外径的关系曲线，表明螺旋桩螺旋部分完全进入土体时螺旋桩圆柱部分所受扭矩随着螺旋导程的增大而减小，随着圆柱外径的增大而增大，这与螺旋桩沉桩试验结论相符合，据此优选出最佳结构的螺旋桩；仿生曲面试验表明，尺寸较小的球冠突起型仿生曲面在一定压力作用下未能起到减粘降阻的作用，而尺寸较大的波纹型仿生曲面相对平板具有一定的减粘降阻作用；以波纹型仿生曲面突起宽度、波纹型仿生曲面两突起之间间距、台车的牵引速度以及叶片表面垂直载荷为因素，以曲面摩擦系数试验指标进行正交试验，寻求出在一定试验条件下最佳因素水平组合；波纹型仿生曲面突起宽度在本试验条件下对曲面摩擦系数影响显著，而其它几个因素对曲面摩擦系数影响均不显著；通过波纹型仿生曲面突起宽度和台车牵引速度的单因素试验，表明曲面摩擦系数随着仿生曲面突起宽度的增大而减小，而随着台车牵引速度的变化基本保持不变，和正交试验结果保持一致。

The cross cylinderis a compound lens having a net minus power in one principal meridian and an equal net plus power in the other.

12交叉圆柱透镜(Jackson 交叉柱镜)是一组复合式镜片，一条主子午线上有单纯负圆柱透镜焦度，在另一主子午线上有一相等的单纯正圆柱透镜焦度

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了