首页
登录
职称英语
[originaltext] The world’s first completely automatic railway has been built
[originaltext] The world’s first completely automatic railway has been built
游客
2023-09-03
89
管理
问题
The world’s first completely automatic railway has been built under the busy streets of London. The railway is called the Victoria Line, and it is part of the complete London underground railway.
The new Victoria Line was opened in 1969. This new line was very different from the others. The stations on the other lines need a lot of workers to sell tickets, and to check and to collect them when people leave the trains. This is all different on the Victoria Line. Here a machine checks and collects the tickets, and there are no workers on the platforms.
On the train, there is only one worker. If necessary, this man can drive the train. But usually he just starts it; it runs and stops by itself. The trains are controlled by electrical signals which are sent by the so-called "command spots".
The command spots are the same distance apart. Each sends a certain signal. The train always moves at the speed that the command spots allow. If the command spot sends no signals, the train will stop.
Most of the control work is done by computers. The computers also fix the train’s speeds, and send the signals to the command spots.
Other machines make sure that the trains are always a safe distance apart. One train may stay too long at a station; the other trains will then automatically move slower. So there is no danger of accidents on the line.
选项
A、Workers on the platforms and trains were replaced by machines.
B、A completely automatic line was added to its network.
C、It became the first completely automatic railway in the world.
D、Its trains became manual-controlled.
答案
B
解析
What happened to the complete London underground railway thirty-nine years ago?
转载请注明原文地址:http://tihaiku.com/zcyy/2981744.html
相关试题推荐
[originaltext]Evenatschooltherehadbeenanunhealthycompetitionbetwee
[originaltext]Evenatschooltherehadbeenanunhealthycompetitionbetwee
[originaltext]Evenatschooltherehadbeenanunhealthycompetitionbetwee
[originaltext]M:Andnow,Mrs.Smith,canyoutelluswhathappenedatyourapa
[originaltext]M:Andnow,Mrs.Smith,canyoutelluswhathappenedatyourapa
[originaltext]M:Andnow,Mrs.Smith,canyoutelluswhathappenedatyourapa
[originaltext]W:Tellmealittlebitaboutyourself,please.M:MynameisDav
[originaltext]W:Tellmealittlebitaboutyourself,please.M:MynameisDav
[originaltext]Readingtooneselfisamodernactivitywhichwasalmostunkn
[originaltext]Readingtooneselfisamodernactivitywhichwasalmostunkn
随机试题
Afence,(stand)______atthebackofourgarden,separatesusfromourneighbor
Thanksinparttotechnologyanditsconstantsoundingandringing,roughly
Thefridgeisconsideredanecessity.Ithasbeensosincethe1960swhenpa
设计题目:手工艺品专卖店 任务要求 在我国南方某城市商业区内拟建一幢规模
患者女,64岁,乏力、腹胀、厌食2年,查体:肝病面容,巩膜轻度黄染,结膜苍白,胸
下列指标中可对微小心肌损伤作出诊断的是A.心肌肌钙蛋白(cTnT,cTnI)
单纯的理性的逻辑方法,难以避免现实上的失误。人们的感情、人们的意志、人们的理想和
我国致力于促进普通高中发展的多样化和特色化,一方面是为了满足社会对人才的多元化需
2022年2月23日,全国人大代表()正式启用,将实现代表议案建议提出、交
存贷比是衡量银行安全性的主要指标。( )
最新回复
(
0
)