线的

Markings. Line Markings defining the field of play are to be at least 2.5 cm.

2.2。标志线。球场的标志线至少2.5cm宽，标志线的布局请看图1。

Being formed by linear grain curved surface, helicoid can be expressed by a group of simple lines. Writing two equations of inside and outside of the helicoid, getting any one of simple line′s equation and from which getting the coordinations of two end points by projection transformation, the CAD system of helicoid is achieved. It...

由于螺旋面为直纹曲面，因此可用它的一组素线表示，用极坐标的形式写出内外两条螺旋线的方程，求出任一素线的方程，并通过投影变换求得素线上两端点的坐标矩阵，进而设计出螺旋面的CAD系统，并将其应用于实践，为设计优化决策提供有力的证据。

The results show that this process is mainly triggered by the upper and lower shear line and the humidity mutation line on the ground is the indication of the squall line formation and development.

结果表明：中低空切变线是此次强对流天气的触发系统，地面湿度突变线对飑线的生成及发展具有指示意义。

According to short term monitoring data, it appears that the new cell echo before the radar echo is advantage for the development and maintenance of the squall line. And the initialization of new cell is associated with boundary-layer convergence line. As a result, mesonet data is useful fur to research on squall line.

从短时监测的资料分析，飑线发展过程中，雷达主回波前方的新生的回波单体对飑线发展和持续十分有利，而它的新生与边界层的辐合线相联系，因此，充分利用中尺度地面观测资料有助于飑线的发展研究。

Some topics for future research, such as nonlinear dynamical behavior of moving strings, vibration of moving viscoelastic strings, control of hybrid systems containing moving strings and control of nonlinear oscillations of moving strings, are suggested.

最后指出该研究方向今后需要研究的若干重要问题，包括运动弦线的非线性动力学行为、黏弹性运动弦线的振动、含运动弦线的混杂系统的控制和轴向运动弦线非线性振动的控制。

According to the helix theories of cylinder,the essential factors of helix with torus are analyzed,and the parametric equation of helix on torus is given based on analytic geometry.

根据圆柱螺旋线理论，分析了形成圆环螺旋线的要素，并运用解析几何方法建立了圆环螺旋线的参数方程。

Do the system research in the choice method of route scheme, putting forward principles, steps, procedure and the method of ecology route selection and the security route selection. This prides a powerful tool for designers in route selection process to reasonable correspond to each kind of influence factor and the solution of design principal contradiction.

系统研究了路线方案选择方法，提出了生态选线和安全选线的原则、步骤、程序和方法，为设计人员在选线过程中合理协调各种影响因素、解决设计主要矛盾提供了有力的工具。

The characters of the singular point of the visible contour line of a concave rotative surface and its corresponding projection are analyzed on condition that the projection of the contour line is smooth near the singular point , the shape of the visible contour line of a concave rotative surface near the singular point is further studied.

对凹回转面可见轮廓线的投影在奇点附近仍光滑的情况下，分析了可见轮廓线本身与奇点对应点处的曲线特征以及可见轮廓线在其对称平面的投影图上与奇点对应的点的特征。对凹回转面可见轮廓线在奇点附近形状作了进一步的分析与研

In the process of the developing of NC machine tool which machines the sleeve of synchromesh of automobile ,efficient methods making use of hypocicloide are introduced.

介绍了用摆线轨迹形成原理加工滑块槽及倒锥的工作原理；结合汽车同步器齿套数控加工机床的研发，提出了利用摆线逼近圆弧和渐开线的高效加工方法；并通过建立摆线的参数方程，分析了其各个参数对摆线形状的影响，进而证明了利用这种方法加工同步器齿套的可行性。

The thickness of the top valance normally is 35MM.

同时吊柜挂件定位、画线时也要注意顶线的厚度，顶线的厚度通常看成35MM。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。