轨迹线

By analytic geometry method and solving quadratic equation,a computer simulation algorithm of digital projection under arbitrary scanning locus was proposed.The algorithm is based on the rules of attenuation of monochromatic X-rays.Through mathematical modeling and computer simulation,digital projections of ellipsoid and cylinder in circular and helix scanning modes are exemplified respectively,which are proved to be correct by FDK and PI-line reconstruction algorithms.

介绍了一种利用解析几何和求解二次方程仿真任意扫描轨迹下的锥束射线投影数据算法，该方法基于单色射线贯穿物体的衰减理论，通过数学建模与计算机仿真，给出了椭球、圆柱两种典型模型分别在单圆、螺旋线扫描轨迹下的投影数据仿真结果，并利用FDK和PI线重建算法进行验证，证明了该种数值仿真方法的正确性。

Theorem 4 it is not the path of integral but the points and in the locus L that affects the line integral of locus L of foot point of the perpendicular line between the origin and the tangent line of the cylindrical spiral .several corollaries are derived from the theorems mentioned above.

定理4 势量场沿由坐标原点至圆柱螺线的切线所引垂线的垂足轨迹L的线积分与积分路径无关，只与轨迹L上的取的端点与有关。并由以上定理得到了几个推论。

The paper analyzed the motion principle of an end-face lapping machine for an optical fibre conneetor,and deduced the expressions for the workpiece′s motion path in relation to its lapping plate and the motion path vise versa,both of which,as shown by Eqs(5) and(6) in the full paper,are trochoid .

推导出工件相对于研磨盘的运动轨迹S1和研磨盘相对于工件的运动轨迹S2的表达式，得出S1、S2均为次摆线，分析了轨迹随相关参数的变化规律。

Formation of a birdnest prevents free movement of goods and may be caused by inadequate tensioning of the top thread top thread not through take-up lever top thread not following thread path correctly or flagging goods.

鸟巢的形成阻碍了图案的自由移动，它可能是因为顶部的线张力不够，顶部的线未穿过紧线器杆顶部的线未准确地沿着线的轨迹，或者是图案下垂了）。

Formation of a birdnest prevents free movement of goods and may be caused by inadequate tensioning of the top thread,top thread not through take-up lever,top thread not following thread path correctly or flagging goods.

鸟巢的形成阻碍了图案的自由移动，它可能是因为顶部的线张力广东服饰批发网，顶部的线未穿过紧线器杆，顶部的线未正确地沿着线的轨迹，或者是图案下垂了）。

Formation of a birdnest prevents free movement of goods and may be caused by inadequate tensioning of the top thread,top thread not through take-up lever,top thread not following thread path correctly or flagging goods.

鸟巢的形成阻碍了阿珍妮女装官方网的自由移动，它可能是因为顶部的线外贸服装英语不够，顶部的线未穿过紧线器杆，顶部的线未正确地沿着线的轨迹，或者是图案下垂了）。

The calculation results shows that ,(1) when the rotor rotates at the working speed, a local regurgitant whirlpool that is rightabout to the rotor"s rotating direction appears in the classifying region, which makes the separated granules come back to the outside of the classification district and influences the classification efficiency of the turbine classifier;(2) in the condition of a low rotating speed of turbo rotor, ultrafine particles can follow the gas phase by and large, but when the rotating speed increases, a phenomenon of velocity slippage between two phases appears evidently;(3) A operating parameter, air flow rate is so important that can directly influence the stability of flow field in classifying chamber, the bigger the air flowrate is , the steadier the flow field is;(4) Compared with straight blades, the new shape of blades with backward crooked elbow are helpful to improve the stability of flow field and form whole stream easily, also beneficial to advance the classification accuracy and classification efficiency;(5) The motion trace of particles are very complicated when the turbo rotor rotates at a high speed, the constant bounce of the particles appear between the blades and the coarse particles are even bounce back from the inlet, only the finer can pass through the classification area from the oulet;(6) Along with the increase of the rotor"s rotating speed, radiah axial and tangential velocity all begain to fluctuate repetitively like sine-wave, the smaller the particles are, the more violently they fluctuates.

数值模拟结果表明，(1)在涡轮达到工作转速时，在分级区域形成了一个与涡轮旋转方向相反的局部回流涡，它使得分离出来的细粒重又被带回分级轮外边缘，从而严重影响分级机的分级效率；(2)粉尘粒子在涡轮低速运动情况下，基本上能跟随气体运动，但随着转速加大，两相之间出现了明显的速度滑移现象；(3)分级机工作时的风量也是一个比较重要的操作参数，它可以直接影响到分级机内腔流场的稳定性，风量越大，流场越稳定；(4)同直叶片形状相比较，带后弯导板的叶片，有利于改善流场的稳定性，流场容易形成整体流，对提高分级效率和分级精度都非常有利；(5)粒子轨迹线在涡轮转速较高时十分复杂，有的出现了反复的弹跳现象，大颗粒不能通过分级区域而从进口返流了，只有细小的颗粒才从出口处流出；(6)涡轮转速加大时，粒子的径向、轴向和切向速率出现了明显的类似于正弦波的脉动现象，颗粒越小，脉动程度越为剧烈。

Velocity and concentration's trajectories are expressed by simple formulas and compared with experimental results.

分别将速度和浓度轨迹线拟合成简单的表达式并与试验拟合作了比较。

According to the wire electrode on the trajectory of the different forms of control, WEDM can be divided into three types:* is a copy-control, cutting their lines in advance to create the shape of the workpiece and the same mode *, When the rough machining parts and die at the same time * Clamping in the machine tool table, in the process of cutting wire electrode tightly * close to the edge of model for mobile track, thus cutting out the model * with the same shape and precision to work; another One is the optical tracking control, the cutting in line before the first parts in accordance with drawings by a certain ratio of enlarge depicts an electro-optical tracking maps, drawings will be processed when the machine electro-optical tracking placed on the stage, followed on the stage The first photo has to follow the ink line graphics track movement, and then through the use of electrical, mechanical linkage to control the machine tool table work together with the relative electrode wire Xiang Sixing do sports in order to cut out the pattern and shape of the workpiece to the same; a re - Is a digital process control, advanced digital automatic control technology, machine-driven process in accordance with the geometry of the workpiece before the parameters of good pre-processing CNC automatic completion of the processing, production do not look like without drawing board also plans to enlarge, in front of more than two Control in the form of higher precision processing and broad scope of application, at home and abroad for more than 95% of WEDM have been using digital technology.

根据对电极丝运动轨迹的控制形式不同，电火花线切割机床又可分为三种：一种是*模仿形控制，其在进行线切割加工前，预先制造出与工件形状相同的*模，加工时把工件毛坯和*模同时装夹在机床工作台上，在切割过程中电极丝紧紧地贴着*模边缘作轨迹移动，从而切割出与*模形状和精度相同的工件来；另一种是光电跟踪控制，其在进行线切割加工前，先根据零件图样按一定放大比例描绘出一张光电跟踪图，加工时将图样置于机床的光电跟踪台上，跟踪台上的光电头始终追随墨线图形的轨迹运动，再借助于电气、机械的联动，控制机床工作台连同工件相对电极丝做相似形的运动，从而切割出与图样形状相同的工件来；再一种是数字程序控制，采用先进的数字化自动控制技术，驱动机床按照加工前根据工件几何形状参数预先编制好的数控加工程序自动完成加工，不需要制作模样板也无需绘制放大图，比前面两种控制形式具有更高的加工精度和广阔的应用范围，目前国内外95％以上的电火花线切割机床都已采用数控化。

Wire electrode based on the trajectory of the different forms of control, WEDM can be divided into three types: one is shaped by the imitation controlled cutting in line in advance and work to create the same shape by mold, when processing the workpiece at the same time rough and on the mold clamping in the machine tool table, in the process of cutting wire electrode tightly against the mold on the edge of the track for the mobile, thus cutting out and die on the same shape and precision to the workpiece; another One is the electro-optical tracking control, to carry out the cutting line, before the basis of certain parts to enlarge the proportion of drawings depicts an electro-optical tracking map-processing machines will be placed in design stage of electro-optical tracking, tracking platform Photoelectric first line of graphics has always been to follow the track of the Mexican campaign, and then through the use of electrical, mechanical linkage to control the machine tool table, together with the workpiece so相似形wire electrode relative movement, thus cutting out the same shape and design to the workpiece; again a digital control, the use of advanced automatic control of digital technology-driven machine tool in accordance with the pre-processing parameters according to the workpiece geometry pre-processing procedures for the preparation of a good CNC auto-complete processing, the production does not require appearance on board the need to map to enlarge map of the previous two form of control has a higher machining accuracy and a broad range of applications, both at home and abroad more than 95% have adopted WEDM NC.

根据对电极丝运动轨迹的控制形式不同，电火花线切割机床又可分为三种：一种是靠模仿形控制，其在进行线切割加工前，预先制造出与工件形状相同的靠模，加工时把工件毛坯和靠模同时装夹在机床工作台上，在切割过程中电极丝紧紧地贴着靠模边缘作轨迹移动，从而切割出与靠模形状和精度相同的工件来；另一种是光电跟踪控制，其在进行线切割加工前，先根据零件图样按一定放大比例描绘出一张光电跟踪图，加工时将图样置于机床的光电跟踪台上，跟踪台上的光电头始终追随墨线图形的轨迹运动，再借助于电气、机械的联动，控制机床工作台连同工件相对电极丝做相似形的运动，从而切割出与图样形状相同的工件来；再一种是数字程序控制，采用先进的数字化自动控制技术，驱动机床按照加工前根据工件几何形状参数预先编制好的数控加工程序自动完成加工，不需要制作靠模样板也无需绘制放大图，比前面两种控制形式具有更高的加工精度和广阔的应用范围，目前国内外95%以上的电火花线切割机床都已采用数控化。切割属电加工范畴，是由前苏联人发明的，我国是第一个用于工业生产的国家，当时由复但大学和苏州长风机械厂合作生产的这是最早的机型叫复旦型，我们国内在此基础上发展了快走丝系统。欧美和日本发展了慢走系统LS

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。