圆柱的

Cartesian, spherical and cylindrical coordinates can be transformed.

笛卡儿，球和圆柱的同等者能够被转变。

The low-dimensional Galerkin method is generalized to solve the flow around arbi-trarily translating circular cylinder.Active control problems of wakes behind circularcylinders are numerically investigated by only small number of modes.The in-line andtransverse oscillation of a circular cylinder with proper frequency produce Karman vor-tex street successfully in some subcritical regime,vhereas the transverse oscillation of acircular cylinder with 1.8 times the natural shedding frequency can effectively suppressthe Karman vortex street at a slightly supercritical Re.

将低维Galerkin方法推广至可以求解任意平移运动圆柱的绕流问题，用较少的模数值研究了圆柱尾迹的主动控制问题，在亚临界Re数下圆柱以适当的频率沿流向和横向振动均成功地激发出Karman涡街；而在略高于临界Re数下圆柱以1.8倍自然脱涡频率沿横向振动明显地抑制了Karman涡街；再现了超临界Re数横向及流向振动圆柱绕流的频率锁定等复杂非线性现象。

Since the multiple scattering should be considered, the scattering problem of many-cylinders is more complicated than single cylinder. By using scattering matrix method to solve the scattering problem of many-cylinders, first we have to express the incident fieldand scattered field by special function（for example, Bessel function and Hankel function）under cylindrical coordinate, then use the addition theorem of special function to get a linear system of equations to relate the incident field coefficients and scattered field coefficients. The incident and scattered field coefficients for every cylinder can be solved from the linear equations by matching electromagnetic boundary condition pointwisely.

单颗圆柱散射体的散射场解析解很早就被解出，而多个圆柱阵列的散射场问题因为涉及到入射光在圆柱与圆柱间的多重散射，故散射行为较单颗圆柱的散射复杂，因此圆柱阵列的多重散射问题需要利用加法定理来处理；散射矩阵法的主要精神即是先用圆柱座标下的特殊函数对平面波和圆柱散射体的内外域电磁场做无穷级数展开，再藉由特殊函数的加法定理将所有圆柱散射体的展开中心移到同一个展开中心，最后可以得到一组连结整个散射系统的入射电磁场系数及散射电磁场系数的线性方程组，将该组线性方程配合电磁场在散射体边界的连续条件，便可分别求出圆柱阵列中各个圆柱体的内部电磁场与外部散射场，再利用线性叠加原理即可求得整个圆柱系统的全域电磁场分布。

Two problems were solved in numerical calculation, one was that a term of 1/r in Maxwell was divergence in cylindrical center where r=0, another was that the value of optical field at cylindrical center was difficult to decided when the cylindrical center set as a boundary condition in Maxwell equation, So the values of optical field need just calculate from cylindrical center to cylindrical boundary, comparing from cylindrical boundary to cylindrical boundary, near upon half CPU time and RAM saved.

计算中解决了在圆柱中心线上Maxwell方程存在发散项1/r以及用圆柱中心线作为边界条件时，中心线上光场值难确定的问题，因而光场只需从圆柱中心计算到圆柱边界，和以圆柱的两条边做为边界条件比较，节省了将近一半的计算时间和计算机存储空间。

The numerical results show that the penetration structure of columns can inflect the flow field and significantly reduce the shear stress and effective permeability.

计算结果表明，圆柱的渗透特性改变了流场的流动特性，显著减小了流动在圆柱表面所产生的剪切应力，改变了阵列的渗透性。

Feature parameters are achieved by comparing the coefficient of standard representation and general representation. As for cone, parameter of general representation has no explicit geometric meaning and can not reflect design intent.

基于二次曲面的统一表示方程，采用最小二乘法进行参数拟合，通过对比其标准形式和二次曲面的统一表示方程，确定圆柱曲面特征带有明显几何意义的参数圆柱轴线法矢量、圆柱的中心和半径。

Because of this, circular runout will not detect changes in size.

圆跳动是对被测圆柱的任一截面圆独立检测，圆跳动检测不到尺寸的变化，被测圆柱的任何桶形，腰形或锥形都将被忽略

We obtain scattering values of the metal cylinder by utilizing the monostatic system.

我们利用单向系统获得金属圆柱体的声场散射值，即：换能器在远场发射声波照射金属圆柱并且在远场同一地点接收金属圆柱的散射值。

When a cylinder and a taper have the same undersides and the same heights, the bulk of the cylinder is 3 times as the bulk of the taper, and the bulk of the taper is 1 third of the bulk of the cylinder.

生：当圆柱和圆锥等底等高，圆柱的体积是圆锥的3倍，圆锥的体积是圆柱的1/3。

It is found that the position of vortex shedding is different fro m three-row cylinders. The time-mean pressure coefficient along the surfaces o f the cylinders is not changed with the void friction. But the fluctuating press ure coefficient reduces with the increase of void fraction.

试验结果表明：沿圆柱表面周向的旋涡分离点随着流动向深层发展，并向圆柱的背部移动；圆柱表面沿周向的时均压力系数几乎不随含气率的变化而变化；圆柱表面的脉动压力系数随着含气率的增加而减小。

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