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
71
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.
【C10】______
选项
答案
but
解析
转载请注明原文地址:https://www.kaotiyun.com/show/rDKd777K
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
Whatistheproblem?
A、 B、 C、 CLet’scleanuptheofficefirstanswerswhatshallwedofirst.Choice(A)confusestheoppositeslast
A、 B、 C、 D、 DSomebusinesspeopleareseatedaroundatable,talkingaboutsomepapersordocuments.Choice
Whatistheman’sbusiness?
Whatistheman’sbusiness?
Whatistheman’sbusiness?
Whatistheproblematthefactory?
CouldyoutellushowimportantyouthinkEnglishwillbeinthefutureforbusinessinChina?
谈论有关全球化、高科技及其他热点话题Jobsatisfactionormoney,whichismoreimportant?
随机试题
肺结核的主要传染源是
患者,男性,64岁。头晕、心悸4~5年,心尖搏动向左下移位,呈抬举性搏动,于胸骨左缘第3、4肋间闻及叹气样舒张期杂音,为递减型,向心尖传导,在心尖区闻及隆隆样舒张早期杂音,股动脉可闻及射枪音,首先应想到的诊断为
2012年2月28日9时4分,A化工公司发生重大爆炸事故,造成25人死亡、4人失踪、46人受伤,直接经济损失4459万元。该公司年产10000t恶二嗪、1500t2-氯-5-氯甲基吡啶、1500t西林钠、1000tN-氰基乙亚胺酸乙酯,项目由县
下面有关保理业务说法不正确的是()。
在公司的组织机构中居于最高层的是()。【2007年真题】
在理论物理中,发现“黑洞辐射”的科学家是()。
中学生晓波通过物理实验发现,钟表的摆动幅度不取决于钟摆的材料或重量,而是取决于钟摆的长度。根据皮亚杰的认知发展阶段理论,晓波的认知发展水平已达到()。
语文教师引导学生分析、评价作品中的人物,从美育的角度看,主要是在引导学生()。
设当x→x0时,α(x),β(x)(β(x)≠0)都是无穷小,则当x→x0时,下列表达式中不一定为无穷小的是()
An instruction is made up of operations that(68)the function to be performed and operands that represent the data to be operated
最新回复
(
0
)