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
70
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
A、 B、 C、 CLet’scleanuptheofficefirstanswerswhatshallwedofirst.Choice(A)confusestheoppositeslast
Whatistheman’sbusiness?
Whatistheproblem?
Whatpositionisbeingadvertised?
Whatkindofbusinessisbeingadvertised?
Howlongdoestheprocessofinternationalshippingdocumentstake?
Istimemanagementimportantornot?Why?
CouldyoutellushowimportantyouthinkEnglishwillbeinthefutureforbusinessinChina?
AahumanresourcesmanagerBawholesalerCasoftwareengineerDanemployeeincustomerservicedepartment
随机试题
A.风中经络证B.风邪犯肺证C.风寒湿痹证D.太阳中风证突起面部麻木,口眼歪斜,微恶风寒,脉浮缓。为
统计标准化
嗜酸性粒细胞增多症外周血嗜酸性粒细胞绝对值大于下列哪一项
女性,33岁,出现右侧腰部剧烈疼痛,经尿常规及B超检查诊断为肾绞痛,应选哪种药物止痛
可以转变为酪氨酸的是脱羧基生成广氨基丁酸的是
监理工程师(包括总监理工程师、驻地监理工程师、专业监理工程师)是一种()。
背景某机电安装公司承接一项炼油厂的塔体群安装工程,工程内容包括:各类塔体就位、各类管道、自动控制和绝热工程等。其中最高塔体为42m,最重塔体102t。合同工期为三个月,合同约定:如果合同工期违约一天罚款10000元,如每提前一天奖励5000元。
一般资料:求助者,女性,66岁,某工厂退休职工。案例介绍:求助者一年前睡觉时突然憋醒,胸闷气短,觉得自己马上就不行了,送入急诊后诊断为呼吸暂停综合症,自己非常后怕,因为自己的哥哥就是夜里突发心脏病去世的,医生也说这种病如不及时发现就会憋死。求助者立
()主要是指秘书人员在自己的职责范围之内,或根据领导的授权,调整和改善部门之间、工作之间、人与人之间的关系,促使机关活动趋向同步化、和谐化,以实现其共同目标的行为过程。
一些人有这样一种思想误区,即只讲“实现自身价值”,不讲“提高自身价值”。人当然天生就有价值,这价值应当重视,但还有待提高。提高不能靠包装与炒作,必须要真正提高质量,具体表现无非就是德与才。这两方面的提高,只有通过克己修身。“玉不琢,不成器”,人不克己修身,
最新回复
(
0
)