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
Even during the horse and carriage days, traffic in big cities was often heavy. Police officers had to be stationed full time di
Even during the horse and carriage days, traffic in big cities was often heavy. Police officers had to be stationed full time di
admin
2013-12-04
37
问题
Even during the horse and carriage days, traffic in big cities was often heavy. Police officers had to be stationed full time directing traffic at busy intersections.
The world’s first traffic light came into being before the automobile was in use, and traffic consisted only of pedestrians, carriages and wagons. On December 10, 1868, the first traffic lights were installed outside the British Houses of Parliament in London, by the railway engineer J. P. Knight. They resembled railway signals of the time, with signaling arms and red and green gas lamps for night use. The gas lantern was turned with a lever at its base so that the appropriate light faced traffic. Unfortunately, it exploded on 2 January 1869, injuring the policeman who was operating it.
The modern electric traffic light is an American invention. As early as 1912 in Salt Lake City, Utah, policeman Lester Wire invented the first red-green electric traffic lights. On 5 August 1914, the American Traffic Signal Company installed a traffic signal system. It had two colors, red and green, and a buzzer, based on the design of James Hoge, to provide a warning for color changes. The design by James Hoge allowed police and fire stations to control the signals in case of emergency. The first four-way, three-color traffic light was created by police officer William Potts in Detroit, Michigan in 1920.
Timers on traffic lights were first seen in Taipei, China, and then brought to the U.S. after an engineer discovered its use. Though uncommon in most American urban areas, timers are still used in some other Western Hemisphere countries. Timers are useful for drivers to plan if there is enough time to attempt to cross the crossroad before the light turns red and the amount of time before the light turns green.
The colors of the traffic lights are psychologically associated with the message they are meant to transmit. Red is classically seen as a color representing danger or caution.(There are countless phrases and idioms that use "red" as a message of the bad or unknown—"in the red" and "seeing red.")Green, on the other hand, is a reassuring color in most cultures—the color of nature and growth; of harmony, freshness, and fertility. Green has a strong emotional correspondence with the idea of safety, and was intuitively chosen to guide pedestrians responsibly through an intersection.
The first electronic traffic light was invented by______.
选项
A、James Hoge
B、J. P. Knight
C、Lester Wire
D、William Potts
答案
C
解析
第三段前两句说现代的电子信号灯是美国人发明的。1912年犹他州盐湖城的警察Lester Wire发明了第一个电子红绿灯。
转载请注明原文地址:https://kaotiyun.com/show/DhHO777K
0
研究生英语学位课统考(GET)
相关试题推荐
Thingshavereallychanged.Notonlyisthemilitarystandingtallagain,itisstagingaremarkablecomebackinthequantityan
Historically,thespread,prevalence,andveryexistenceofcontagiousdiseasehavewhollydependedonthegrowthandconcentrat
Today’sworkerisnolongerwillingtoworkinanauthoritariananddehumanizingenvironment.Workerswantmeaningintheirwork
Whydopeoplealwayswanttogetupanddancewhentheyhearmusic?Theusualexplanationisthatthereissomethingembeddedin
Whydopeoplealwayswanttogetupanddancewhentheyhearmusic?Theusualexplanationisthatthereissomethingembeddedin
Eatingisrelatedtoemotionalaswellasphysiologicneeds.Sucking,whichistheinfant’smeansofgainingbothfoodandemoti
Thenewcomersfounditimpossibleto______themselvestotheclimatesufficientlytomakepermanenthomesinthenewcountry.(厦门
AnOhioStateUniversitystudyhaslinkedbehaviorinyoungchildren【C1】______thetypeofjobtheirmotherhas.Motherswithcom
许多国际体育比赛的业余组织者经常抱怨说,体育道德已不复存在了。他们把体育方面出现的问题全部归咎于日益增长的职业化。他们震惊地看到,现在有些运动员把赛跑当工作,参加赛跑就要得到报酬。他们宣称,当现代奥林匹克运动会兴起时,运动员觉得参加比赛本身就是一种奖励,别
HadPaulreceivedsixmorevotesinthelastelection,he______ourchairmannow.
随机试题
现代计算机硬件系统的性能发展瓶颈是()。
阿托品抗休克的主要机制是
A.胸部剧痛,入夜尤甚B.胸闷隐痛,时作时止C.胸闷如窒,气短喘促D.胸闷气短,畏寒肢冷E.胸痛彻背,感寒痛甚胸痹气阴两虚证,其临床特点是()
风险的主要特征包括()。
根据企业所得税法律制度的规定,下列关于长期待摊费用的说法中,正确的有()。
阅读材料有人主张,动物尤其是略微高等的动物,完全同人一样,生来就有一种由遗传而得到的潜在的教育,其效果见诸个体的发展过程,他认为,从观察得到的,互相有联系的许多事实已无争辩的证实:兽类教育和人类教育在根本上有同样的基础,由人强加的人为的教育,可移
关于2010年部分节假日安排的通知××××:经县政府批准,现将2010年部分节假日安排通知下发给你们。根据《国务院关于修改的决定》,为便于各单位、各部门及早合理安排节假日旅游、交通运输、生产经营等有关工作,经国务院批准,2010年部分节假日放假调休日
下列行为中不属于行政行为的是()。
下列指令中,不影响标志位SF位的指令是( )
请在“答题”菜单中选择相应的命令,并按照题目要求完成下面的操作。注意:以下的文件必须保存在考生文件夹下。文君是新世界数码技术有限公司的人事专员,十一过后,公司招聘了一批新员工,需要对他们进行入职培训。人事助理已经制作了一份演示文稿的素材“新员工入职培训
最新回复
(
0
)