首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly. Researchers have
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly. Researchers have
admin
2010-01-10
103
问题
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly.
Researchers have learned that the slapping noise pigeons make when they suddenly take off is the sound of super charged lift. They call it the "clap fling" effect.
Here at SRI International scientists try to duplicate the pigeons’ thrust. A flashing strobe reveals the secret.
Scott Stanford, a scientist at SRI, says, You re looking at the clap fling effect, where the two wings will come together and peel apart 【C2】______ each other, thus augmenting lift 【C3】______ drawing air from the top to the bottom. "
This mechanical bug won’t get off the ground. 【C4】______ its flapping wings demonstrate a potential propulsion system for robotic birds: man-made rubbery muscle.
Roy Kornbluh works at SRI. "There, I’m turning the voltage on and off, and you can see when the voltage is on, the material is larger 【C5】______ when the voltage is off."
Super computers show high-speed airflows over supersonic aircraft.
But scientists have only begun to see how air flows 【C6】______ really low speeds.
Professor Max Platzer of the Naval Postgraduate School, says, "The flapping wing is generating a thrust, this way, this is the basic physics of the phenomenon."
It’s pelicans--not pigeons--the Navy is looking at. The Navy is looking at the smooth easy flight of pelicans low over water--called "ground effect." Researchers at the Naval Postgraduate School are trying to imitate the pelican’s efficiency.
Assistant Professor Kevin Jones of the Naval Postgraduate School says, " 【C7】______ flapping the wings, symmetrically, we’re 【C8】______ effect imitating ground effect. We now have the same feature a bird sees when it’s flying, over a ground plane."
An electric motor drives the flapping wings. Researchers here are working 【C9】______ ways to beam power to the tiny bird.
David Jenn of the Naval Postgraduate School says, "There’s no battery inside of here, so we’re going to set this inside the radar beam, and the energy is extracted from the radar beam and will be used to propel the motor."
Scientists are learning it’s one thing to build an airplane, 【C10】______ quite another to build a bird.
【C4】______
选项
答案
but
解析
转载请注明原文地址:https://kaotiyun.com/show/vDKd777K
本试题收录于:
BEC高级阅读题库BEC商务英语分类
0
BEC高级阅读
BEC商务英语
相关试题推荐
WhattypeofbusinessdoesJackWilliamsown?
Whatpositionisbeingadvertised?
Whatistheproblematthefactory?
Whatpositionarethecandidatesapplyingfor?
Isenvironmentprotectionimportant?Why?
BusinessStrategy:thefactorsinvolvedininfluencingmarkettrendsratherthanreactingtothem
SalesReductionYourcompanyisaninternationalcompanywhichproduceselectronicproducts.Yourcompany’ssaleshavereducedr
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—-12,completethenotes,
AahumanresourcesmanagerBawholesalerCasoftwareengineerDanemployeeincustomerservicedepartment
随机试题
脊柱的体表定位标志,与胸骨剑突在同一平面的椎体是
A.曲马多B.美沙酮C.胰岛素D.麦角新碱E.司可巴比妥属于第二类精神药品的是()。
下列情形属于信用证欺诈的有()
工程项目施工过程中,质量监督机构的职责有()
关于暂列金额,下列说法错误的是()。
交易所会员如对结算结果有异议()。
甲企业为工业企业,拥有三幢房产,分别为厂房A、厂房B和一幢办公楼,其中厂房A为与乙企业和丙企业共同共有,2017年有关甲企业房产的事项如下。(1)甲企业准备将厂房A进行内部装修,添置新的附属设施,经查,甲、乙、丙三个企业事先均没有约定处理方式,甲企业与乙
人的心理是一种动态的活动过程,包括________、情绪过程和意志过程。它们从不同的角度能动地反映着客观世界的事物及其关系。
“抽象与具体相结合”是数学教学原则中的内容。怎样理解数学的抽象性与具体性;
定积分x2(sinx+1)dx=___________.
最新回复
(
0
)