铲背

The automatic generation of logarithmic spiral is achieved by means of the language of VBA embedded in AutoCAD.

提出铲齿成形铣刀齿背曲线的最佳线形应是对数螺线，而后运用AutoCAD的内嵌编程语言VBA，实现了对数螺线齿背曲线的自动生成。

However, logarithmic spiral can be used to substitute for the Archimedes curve to solve such problems and guarantee the stability of cutter machinability .

传统的阿基米德螺线齿背的铲齿成形铣刀在重磨前刀面后，切削刃上各点的后角将发生变化，从而影响刀具切削性能的稳定。

Calculation and Analysis of the Contact Strength of Logarithmic Spiral Profile Connection

若改用对数螺线作为铣刀铲背曲线，则克服了阿基米德螺线的不足。

However, logarithmic spiral can be used to substitute for the Archimedes curve to solve such problems and guarantee the stability of cutter machinability.

若改用对数螺线作为铣刀铲背曲线，则克服了阿基米德螺线的不足。

In case that it happen again,i'd better burry the well.what's more,it can also ease the donkey'spain.the donkey dose not have to be starved to death.he decided to call some of his friends to help him do the work.few hours passed,he came back with a group of farmers with shovels in their hands and started ,soon,the donkey realised what was going to happen,it screamed desperately.but some time later,it became silent.with great surprise,the farmers found that with every shovel of dirt fall to the back of the donkey,it shaked it off and stepped on it,in this way,it stepped upper and upper.finally, the donkey was saved.

以防再有人掉进去，还是把井填起来的好。驴子也可以死的不那么痛苦。他决定叫朋友一起帮忙把井填起来。没过多久，他带着一群拿着铲子的农夫回到井边。填井工作开始了，驴子马上意识到农夫们的意图，叫得更加歇斯底里。但过了一会儿，驴子不再叫了。农夫们往井里望去，惊奇地发现，随着每一铲土掉到驴子的背上，驴子就把它都下来，踩在脚下，让自己站得更高一点。最后，驴子获救了。

The animal , however, shakes actually off earth aside which is shovelled onto its back by the people and stands on the rideau .Soon, it is up to the mouth of the well.

可是当铲进井里的泥土落在驴子的背上时，驴子竟然将泥土抖落在一旁，然后站在泥土堆上面，很快驴子便上升到井口。

It suddenly dawned on him that every time a shovel load of dirt landed on his back, HE WOULD SHAKE IT OFF AND STEP UP!

它突然意识到，每当一铲土打落在它的背上时，它都可以把土抖掉，再踏上去！

It suddenly dawned on him that every time a shovel load of dirt landed on his back he should shake it off and step up.

它突然想到每一铲泥土落到它背上的时候，它应该把泥土抖下来然后踩上去。

For the relieving shaped milling cutter with the traditional Archimedes back curve, the relief angle of each point on the cutting edge is changed after refacing the cutter.

传统的阿基米德螺线齿背的铲齿成形铣刀在重磨前刀面后，切削刃上各点的后角将发生变化，从而影响刀具切削性能的稳定。

But as the farmer and his neighbours continued shovelling and the dirt hit his back, a thought struck him.

但是当农夫和他的邻居们继续铲土并且土不断地打在骡子背上的时候，骡子突然想到了一个主意。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。