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    2012年职称英语测验综合类浏览填空题5

    作者: admin 作者QQ: 时间: 2020-05-14 06:32阅读:

      为了协助广阔考生有效备考2012年全国职称英语综合类测验,小编特编辑整顿了职称英语测验温习资料,欲望对您系统控制2012年职称英语综合类测验的重点内容,顺利经过职称英语测验有所协助。

      Rescue platform 救生平台

      In the aftermath of the terrorist attacks on the World Trade Center, security experts are trying to develop new ways of rescuing people from burning skyscrapers. One idea is a platform capable of flying vertically and hovering in the air like a helicopter. The platform would rise up and down alongside a skyscraper and pick up people trapped in high stories.

      The idea for the vertical takeoff platform was hatched more than ten years ago by a Russian aerospace engineer, David Metreveli, who has since moved to Israel. Metreveli's design, called the Eagle, calls for two jet engines that turn four large horizontal propellers. The spinning of the propellers generates the necessary lift, or upward force, to raise the platform. The more power is supplied to the propellers, the higher the platform rises. Moving the platform sideways involves applying differing amounts of power to each propeller.

      Helicopters are now used in some cases to get people out of burning buildings. Escape baskets slung from them dangle beside the building for people to climb into. Unfortunately, the baskets cannot reach every floor of a building because the ropes from which they hang become unstable beyond a certain length.

      So far, Metreveli has built a small-scale model of the Eagle to test his idea. In the wake of September 11, he has been able to secure enough funding to start building a larger, 4-meter by 4-meter prototype, which he calls the Eaglet.

      活着界贸易中间遭到恐怖攻击后,平安专家们正在尽力寻觅新方法,来从熄灭的摩天大年夜楼上救援人们。个中的想法主意之一就是构建一个可以垂直起落并像直升机一样在空中盘旋的平台。该平台可沿摩天大年夜楼高低移动,输送高楼受困人员。

      十多年前,一名俄罗斯航空航天工程师David Metreveli酝酿出垂直起落平台这一想法主意,随后移居以色列。Metreveli的设计计划定名为“老鹰”,需用两个喷气提议机来推动四个大年夜型水平标的目标扭转的螺旋推动器。螺旋推动器快速扭转,生成需要的上升力,使平台升起。供应螺旋推动器的能量越多,平台升得就越高。要使平台侧向移动,则需求给螺旋推动器添加不等的能量。

      现在,人们有时还用直升机救援起火大年夜楼中的被困人员。从直升机中抛出的救生篮在大年夜楼旁摇晃,人们可以爬到外面去。不幸的是,因为悬挂救生篮的绳索在超越必然长度后就会十分不动摇,所以救生篮没法到达每层楼。

      今朝,Metreveli曾经建立起一个小型“老鹰”模型,来检测自己的构想。“9·11”工作后,Metreveli取得了足够的基金,末尾构建一个较大年夜范围的模型。该模型大年夜小为4公尺×4公尺,他为之定名为“小鹰”。

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