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
考研
Despite increased airport security since September 11th, 2001, the technology to scan both passengers and baggage for weapons an
Despite increased airport security since September 11th, 2001, the technology to scan both passengers and baggage for weapons an
admin
2019-05-30
27
问题
Despite increased airport security since September 11th, 2001, the technology to scan both passengers and baggage for weapons and bombs remains largely unchanged. Travellers walk through metal detectors and carry-on bags pass through x-ray machines that superimpose colour-coded highlights, but do little else. Checked-in luggage is screened by "computed tomography", which peers inside a suitcase rather like a CAT scan of a brain. These systems can alert an operator to something suspicious, but they cannot tell what it is.
More sophisticated screening technologies are emerging,
albeit
slowly. There are three main approaches: enhanced x-rays to spot hidden objects, sensor technology to sniff dangerous chemicals, and radio frequencies that can identify liquids and solids.
A number of manufacturers are using "reflective" or "backscatter" x-rays that can be calibrated to see objects through clothing. They can spot things that a metal detector may not, such as a ceramic knife or plastic explosives. But some people think they can reveal too much. In America, civil-liberties groups have stalled the introduction of such equipment, arguing that it is too intrusive. To protect travellers ’modesty, filters have been created to blur genital areas.
Machines that can detect minute traces of explosive are also being tested. Passengers walk through a machine that blows a burst of air, intended to dislodge molecules of substances on a person’s body and clothes. The air is sucked into a filter, which instantaneously analyses it to see whether it includes any suspect substances. The process can work for baggage as well. It is a vast improvement on today’s method, whereby carry-on items are occasionally swabbed and screened for traces of explosives. Because this is a manual operation, only a small share of bags are examined this way.
The most radical of the new approaches uses "quadrupole resonance technology". This involves bombarding an object with radio waves. By reading the returning signals, the machines can identify the molecular structure of the materials it contains. Since every compound—solid, liquid or gas—creates a unique frequency, it can be read like a fingerprint. The system can be used to look for drugs as well as explosives.
For these technologies to make the jump from development labs and small trials to full deployment at airports they must be available at a price that airports are prepared to pay. They must also be easy to use, take up little space and provide quick results, says Chris Yates, a security expert with Jane’s Airport Review. Norman Shanks, an airport security expert, says adding the new technologies costs around $100,000 per machine; he expects the systems to be rolled out commercially over the next 12 months. They might close off one route to destroying an airliner, but a cruel certainty is that terrorists will try to find others.
The delay of employment of x-ray equipment lies in its______.
选项
A、unreliable screening
B、full exposure
C、inadequate efficiency
D、travellers’modesty
答案
B
解析
这是一道细节分析题,测试考生对原文细节的全面分析能力。本题答案的信息来源在第三段的倒数第二、三句,其大意是:“但是一些人认为X光探测技术显示的内容过多。在美国,民权组织阻碍了X光探测技术仪器的引入和使用,他们认为这种仪器具有过度的侵扰性”。由此可以推断本题的正确选项应该是B。考生在阅读时要注意对原文细节的准确分析和理解。
转载请注明原文地址:https://kaotiyun.com/show/CGnZ777K
0
考研英语一
相关试题推荐
Nonverbalcommunicationisgreatlyimportant:inanyinteractionwithothers;itsimportanceismultipliedacrosscultures.This
Nonverbalcommunicationisgreatlyimportant:inanyinteractionwithothers;itsimportanceismultipliedacrosscultures.This
LatinAmerica—aplacelongassociatedwithfinancialdisaster—hasremainedimprobablycalm,whiletheripplesofAmerica’ssubpr
Youshouldassume,intryingforjobs,thatyouwillnotbetheonlyapplicant.Thesinglemostprevalentdecidingfactoristhe
Directions:Youboughtadigitalcamerainastorelastweek,andyouhavefoundthatthereissomethingwrongwithit.Writ
Forhundredsofmillionsofyears,turtles(海龟)havestruggledoutoftheseatolaytheireggsonsandybeaches,longbeforethe
Anyonewhohassearchedforajobfreshoutofcollegeknowshowdifficultitistogetthatfirstjob.Sendingouthundredsof
Howmenfirstlearnedtoinventwordsisunknown;inotherwords,theoriginoflanguageisamystery.Allwereallyknowistha
Threehundredyearsagonewstravelledbywordofmouthorletter,andcirculatedintavernsandcoffeehousesintheformofpa
随机试题
A.切口位于睑结膜面,与睑缘平行B.切口位于睑结膜面,与睑缘垂直C.切口位于睑皮肤面,与睑缘平行D.切口位于睑皮肤面,与睑缘垂直E.切口在睑缘处
男,22岁。右股骨下端疼痛2月。体检:右股骨下端偏内侧局限性隆起,皮温略高,皮肤浅静脉怒张,明显压痛,膝关节运动受限。X线片股骨下端溶骨性骨破坏,可见Codman三角。诊断为
最可能的诊断是如患者伴有左侧上下肢无力,则病变位于
A.BPB.USPC.ChPD.EPE.LP英国药典的缩写是
根据我国《建设工程安全生产管理条例》的规定,县级以上人民政府建设行政主管部门或者其他有关行政管理部门的工作人员,有( )行为之一的,给予降级或者撤职的行政处分;构成犯罪的,依照刑法有关规定追究刑事责任。
载明日期的要约,以信件发出的,承诺期限自()开始计算。
“豫剧四旦”是指()、马金凤、阎立品、崔兰田。
1,1,16,64,169,()
近几年,人们的生活水平有了显著地提高。
Wisebuyingisapositivewayinwhichyoucanmakeyourmoneygofurther.Thewayyougoaboutpurchasinganarticleoraservi
最新回复
(
0
)