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
In April 1995, a young Chinese chemistry student at Beijing University lay dying in a Beijing hospital. She was in a coma, and a
In April 1995, a young Chinese chemistry student at Beijing University lay dying in a Beijing hospital. She was in a coma, and a
admin
2011-01-02
87
问题
In April 1995, a young Chinese chemistry student at Beijing University lay dying in a Beijing hospital. She was in a coma, and although her doctors had performed numerous tests, they could not discover what was killing her. In desperation, a student friend posted an SOS describing her symptoms to several medical bulletin boards and mailing lists on the Internet. Around the world, doctors who regularly checked these electronic bulletin boards and lists responded immediately.
In Washington D. C. , Do, John Aldis, a physician with the U.S. Department of State, saw the message from China. Using the Internet, he forwarded the message to colleagues in America. Soon an international group of doctors joined the e- mail discussion. A diagnosis emerged -- the woman might have been poisoned with thallium, a metal resembling lead. A Beijing laboratory confirmed this diagnosis -- the thallium concentration in her body was an much as 1,000 times normal. More e-mail communication followed, as treatment was suggested and then adjusted. The woman slowly began to recover. Well over a year later, the international medical community was still keeping tabs on her condition through the electronic medium that saved her life.
It’s 11: 30 p. m. , you’re is San Francisco on business, and you want to check for messages at your office in Virginia. First you dial in and get your voice mail. Next you plug your portable computer into the hotel-room telephone jack, hit a few keys, and pick up e-mall from a potential client in South Africa, your sister in London, and a business associate in Detroit. Before writing your response, you do a quick bit of search on the Internet, tracking down the name of the online news group you had mentioned to the man in Detroit and the title of a book you wanted to recommend to your sister. A few more keystrokes and in moments your electronic letters have reached London and Detroit. Then, knowing that the time difference means the next workday has begun in South Africa, you call there without a second thought.
These stories reflect society’s increasing reliance on system of global communication that can link you equally easily with someone in the next town or halfway around the world. The expanded telephone-line capacity that has allowed the growth of these forms of communication is a recent phenomenon. The United States has enjoyed domestic telephone service for more than a century, but overseas telephone calls were difficult until relatively recently. For a number of years after World War Ⅱ, calls to Europe or Asia retied on short-wave radio signals. It sometimes took an operator hours to set up a 3- minute call , and if you got through, the connection was often noisy.
In 1956, the first transatlantic copper wire cable allowed simultaneous transmission of 36 telephone conversations -- a cause for celebration then, a small number today. Other cables followed; by the early 1960s, overseas telephone calls had reached 5 million per year. Then came satellite communication in the middle 1960s, and by 1980, the telephone system carried some 200 million overseas calls per year. But as demands on the telecommunication system continued to increase, the limitations of current technology became apparent. Then, in 1988, the first transatlantic fiber-optic cable was laid, and the "information superhighway" was on its way to becoming reality.
Optical fibers form the backbone of the global telecommunication system stronger, length for length, than steel -- were designed to carry the vast amounts of data that can be transmitted via a relatively new form of light-tightly focused laser. Together, lasers and optical fibers have dramatically increased the capacity of the international telephone system. A typical fiber-optic cable made up of 100 or more such fibers can carry more than 40,000 voice channels. With equally striking improvements in computing, the new communication technology has fueled the exponential growth of the phenomenon known as the Internet.
The information superhighway came into existence because of ______.
选项
A、copper wire cables
B、satellite communication
C、optical fibers
D、laser and optical fibers
答案
D
解析
该题问:信息高速公路成为现实是因为什么? A项意为“铜丝电缆”,这在文中提到是在第五段In 1956,the first transatlantic Copper Wire cable allowed simultaneous transmission of 36 telephone conversations—a cause for celebration then,a small number today,那时信息高速公路还未存在,因此A项不正确。B项意为“卫星通讯”,这在文中提到也是在第五段Then came satellite communication in the middle 1960s,那个时候信息高速公路也未存在。C项意为“视觉纤维”,这在文中提到也是在第五段Then in 1988,the first transatlantic fiber-optic cable was laid,and the "information superhighway" was on its way to becoming reality,此句写的时间是on its way,所以 C项也不正确。D项意为“激光与视觉纤维”,这在本文中的最后一段的第一句提到,因此D项为正确选项。
转载请注明原文地址:https://www.kaotiyun.com/show/yZlO777K
0
专业英语八级
相关试题推荐
Cultureshockisapainfulexperiencewegothroughwhenweencountermanynewthingsinanothercountryandwe【1】______insom
Contrasttoresearchers’expectations,dysfunctionalfamilyrelationshipsandpoorcommunica-【M1】_____tionstylesappe
Sincehisarrestbyhisownformerpoliceforce,ex-SerbianandYugoslavpresidentSlobodanMilosevichasgonepublicwitharev
TheInternetofthefutureshouldbeaworldwidemarketplacefullyaccessiblebymobilecustomerseverywhere,theleadingnetwor
A、assuredhisfamilymembersthathewassafeB、askedtheBritishgovernmenttosavehislifeC、criticizetheBritishgovernment
Wecomeindifferentcolors:red,black,white,yellowandbrown,haveavarietyofpoliticalsystems,socialsystems,religious
1 Someconsumerresearchersdistinguishbetweenso-calledrationalmotivesandemotional(ornon-rational)motives.Inamarket
传说在漓江淹死的水手变成了鬼,这种鬼会拽航行于急流中的船只。当船经过村庄,竹林和迷雾萦绕的山冈的时候,船上的人有种面对一幅中国国画而觉得时间倒流的感觉。本地的筏子实际上依然靠人力拖着逆流而上,有些是由男人和女人牵引。途中,著名的山景映入眼帘:象鼻山
Ithasalwaysbeendifficultforthephilosopherorscientiststofittimeintohisviewoftheuniverse.PriortoEinsteinianp
______’sLeavesofGrassisacollectionofpoemswritteninfreeverse.
随机试题
一正常婴儿,体重7.5kg,身长68cm,前囟0.5cm×0.5cm,头围44cm,出牙4颗,能独坐,并能左右转身,能以拇、示指拾物,喜撕纸。该儿最可能的月龄是
产后阴道黏膜皱襞重新出现约需()
视网膜结核主要的临床表现不包括
某农户与乡政府签订承包合同,承包一千亩国有荒山进行植树造林,则承包期内,该农户对该块荒山享有()。
实行竣工验收备案制度的工程有()
进境种苗所带的栽培介质需要审批。土壤不属于栽培介质。( )
“110”报警服务台的开通,加快了违法犯罪信息的传递,也使警民联系的渠道更畅通、更便捷。()
假设今天你参加招警面试时碰巧有一位考官曾是你的老师。并且他对你的评价一直不是很好。这对你的面试会有影响吗?
系统软件是随计算机出厂并具有通用功能的软件。下列不属于系统软件的是
A、He’sbeenintheprogramforseveraldays.B、He’sworkinghardontheprogram.C、Heworksonlyduringtheday.D、Hewillproba
最新回复
(
0
)