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
专升本
The biggest safety threat facing airlines today may not be a terrorist with a gun, but the man with the portable computer in bus
The biggest safety threat facing airlines today may not be a terrorist with a gun, but the man with the portable computer in bus
admin
2019-01-24
28
问题
The biggest safety threat facing airlines today may not be a terrorist with a gun, but the man with the portable computer in business class. In the past 15 years, pilots have reported well over 100 incidents that could have been caused by electromagnetic interference.
The source of this interference remains unconfirmed , but increasingly, experts are pointing the blame at portable electronic device such as portable computers, radio and cassette players and mobile telephones.
RTCA, an organization which advises the aviation(航空)industry, has recommended that all airlines ban(禁止)such devices from being used during "critical" stages of flight, particularly take-off and landing. Some experts have gone further, calling for a total ban during all flights. Currently, rules on using these devices are left up to individual airlines. And although some airlines prohibit passengers from using such equipment during take-off and landing, most are reluctant to enforce a total ban, given that many passengers want to work during flights.
The difficulty is predicting how electromagnetic fields might affect an aircraft’ s computers. Experts know that portable device emit radiation which affects those wavelengths which aircraft use for navigation and communication. But, because they have not been able to reproduce these effects in a laboratory, they have no way of knowing whether the interference might be dangerous or not.
The fact that aircraft may be vulnerable(易受损的)to interference raises the risk that terrorists may use radio systems in order to damage navigation equipment. As worrying, though, is the passenger who can ’ t hear the instructions to turn off his radio because the music’ s too loud.
Why is it difficult to predict the possible effects of electromagnetic fields on an airplane’ s computers?
选项
A、Because it is extremely dangerous to conduct such research on an airplane.
B、Because it remains a mystery what wavelengths are liable to be interfered with.
C、Because research scientists have not been able to produce the same effects in labs.
D、Because experts lack adequate equipment to do such research.
答案
C
解析
第三段because后面给出了解释:因为他们不能在实验室重现这些影响,所以他们没办法知道干扰是不是有危险。所以选C。A文中没有说过,B和第二句相反,D没有提到。
转载请注明原文地址:https://kaotiyun.com/show/9AaC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
Manypeoplearewonderingifitissafetotalkonthephonewhiledriving.Therehavebeenquiteafewaccidentswhiledrivers
JohnPaulJoneswasoneofthefoundersoftheUnitedStatesNavy.DuringtheRevolution,thecoloniesweredesperate.Theyneed
Hawaii,theyoungeststateoftheUnitedStates,isdifferentinmanywaysfromthemainlandstates.TheHawaiianpeopleaream
A.IknowagoodplaceB.You’rewelcomeC.NotreallyD.havesomethingtodrinkE.AnyoneF.there’snothinggoodG.Anysu
Thestrangecloseunderstandingbetweentwinsisafamiliarenoughphenomenon.Oftentheyseemtounderstandeachotherandshar
Unlikemodernanimalscientists,dinosaurscientistscannotsitonahillsideandusetelescopestowatchdinosaursinorderto
ResearchershavefoundthatREM(rapideyemovement)sleepisimportanttohumanbeings.Thistypeofsleepgenerallyoccursfour
TheNobelPrizesareawardsthataregiveneachyearforspecialthingsthatpeopleorgroupsofpeoplehaveachieved.Theyare
Atfirstglance,therehardlyseemstobeanycomparisonbetweenRavennaandRome,butbackinthe5thcentury,itwasRavennat
随机试题
某学生的智力年龄为10岁9个月,实际年龄为10岁,他的智商属于()。
试述急性肾衰竭少尿期的临床表现及影响?
肝功能严重受损时血浆中将呈现含量降低的是
下列哪些现象有助于单侧肾动脉狭窄的诊断
A.外感风寒证B.外感风湿证C.暑湿痠毒证D.寒湿困脾证E.气血两虚证
某县人民法院在审理况某故意伤害案中,发现被告人可能有法定的量刑情节,但人民检察院所移送的证据材料中却不具备这方面的内容。对此,合议庭的下列做法中,符合刑事诉讼法规定的是()
教育目的的功能有【】
相对于“学者”而言,“评论家”常常会给人一种特定的印象:短平快的犀利文风,敏感度极高,对作品的形式、技巧、风格、流派如数家珍;但同时也会显出“浮躁”的所谓“评论家”做派,凭印象感觉率性发声,缺少严格的学理支撑,从而坠入肤浅的窠臼。相对于扎实的考史订伪的学者
作为调节社会经济运行的一种重要经济杠杆,下面不能体现提高税率功能的是()
位于我国和巴基斯坦边界上的喀喇昆仑山脉有许多高峰,其中乔戈里峰是世界的()。
最新回复
(
0
)