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
The car, and the roads it travels on, will be revolutionized in the twenty first century. The key to tomorrow’s "smart cars" wil
The car, and the roads it travels on, will be revolutionized in the twenty first century. The key to tomorrow’s "smart cars" wil
admin
2017-06-11
44
问题
The car, and the roads it travels on, will be revolutionized in the twenty first century. The key to tomorrow’s "smart cars" will be sensors. "We’ll see vehicles and roads that see and hear and feel and smell and talk and act," predicts Bill Spreitzer, technical director of General Motors Corporation’s ITS program, which is designing the smart car and road of the future.
Approximately 40, 000 people are killed each year in the United States in traffic accidents. Fully half of these fatalities come from drunk drivers, and many others from carelessness. A smart car could eliminate most of theses car accidents. It can sense if a driver is drunk via electronic sensors that can pick up alcohol vapor in the air, and refuse to start up the engine. The car could also alert the police and provide its precise location if it is stolen.
Smart cars have already been built which can monitor one’s driving and the driving conditions nearby. Small radars hidden in the bumpers can scan for nearby cars. Should you make a serious driving mistake, the computer would sound an immediate warning.
At the MIT Medial Lab, a prototype is already being built which will determine how sleepy you are as you drive, which is especially important for long-distance truck drivers. The monotonous, almost hypnotic process of staring at the center divider for long hours is a grossly underestimated, life-threatening hazard. To eliminate this, a tiny camera hidden in the dashboard can be trained on a driver’s face and eyes. If the driver’s eyelids close for a certain length of time and his or her driving becomes erratic, a computer in the dashboard could alert the driver.
Two of the most frustrating things about driving a car are getting lost, and getting stuck in traffic. While the computer revolution is unlikely to cure theses problems, it will have a positive impact. Sensors in your car tuned to radio signals from orbiting satellites can locate your car precisely at any moment and warn of traffic jams. We already have twenty-four Navstar satellites orbiting the earth, making up what is called the Global Positioning System. They make it possible to determine your location on the earth to within about a hundred feet. At any given time, there are several GPS satellites orbiting overhead at a distance of about 11,000 miles. Each satellite contains four "atomic clocks" , which vibrate at a precise frequency, according to the laws of the quantum theory.
As a satellite passes overhead, it sends out a radio signal that can be detected by a receiver in a car’s computer. The car’s computer can then calculate how far the satellite is by measuring how long it took for the signal to arrive. Since the speed of light is well known, any delay in receiving the satellite’s signal can be converted into a distance. In Japan there are already over a million cars with some type of navigational capability.(Some of them locate a car’s position by correlating the rotations in the steering wheel to its position on a map)
With the price of microchips dropping so drastically, future applications of GPS are virtually limitless, " The commercial industry is poised to explode," says Randy Hoffman of Magellan Systems Corp. which manufactures navigational systems. Blind individuals could use GPS sensors in walking sticks, airplanes could land by remote control, hikers will be able to locate their position in the woods— the list of potential uses is endless.
According to paragraph 5, how can you determine your location on the earth to within about a hundred feet?
选项
A、Via radio signals
B、Via sensors
C、Via GPS
D、Via the quantum theory
答案
C
解析
细节题。从第5段可知,我们能在100英尺范围内确定位置,原因是在11000英里之外的高空中,有几个GPS卫星正按轨道飞行。因此,C为正确答案。
转载请注明原文地址:https://jikaoti.com/ti/DLmYFFFM
0
考博英语
相关试题推荐
Eachyear,millionsofpeopleinBangladeshdrinkgroundwaterthathasbeenpollutedbynaturallyhighlevelsofarsenicpoison.
ThismonthSingaporepassedabillthatwouldgivelegalteethtothemoralobligationtosupportone’sparents.CalledtheMai
InTheBirthOrderBook:WhyYouAretheWayYouAre(2004),Dr.KevinLemannotesthat21ofthefirst23Americansinspacewer
Thewealthofacountryshouldbemeasured_____thehealthandhappinessofitspeopleaswellasthematerialgoodsitcanprodu
Futuristshaveidentifiedtwochangesthatseemtobecentraltocontemporarysociallife.First,theU-nitedStatesisbeingre
Oneofthemajordifferencesbetweenmanandhisclosestlivingrelativeis,ofcourse,thatthechimpanzeehasnotdevelopedthe
Duringthepastgeneration,theAmericanmiddle-classfamilythatoncecouldcountonhardworkandfairplaytokeepitselffin
The____beautyofthemountainhasmadeitaworld-famousresort.Everyyearnumeroustouristsfromhomeandabroadcometovisit
Thirty-onemillionAmericansareover60yearsofage,andtwenty-ninemillionofthemarehealthy,busy,productivecitizens.By
Thirty-onemillionAmericansareover60yearsofage,andtwenty-ninemillionofthemarehealthy,busy,productivecitizens.By
随机试题
()许多凝析气油田在开采时,从井底喷上来的气体在井口附近由于压力和温度降低而转化为汽油。
(2007)Thewashingmachineneeds______beforeitcanbeused.
对于压力不高,介质为气体、液体和无渗漏危险的场所,仪表阀门可选用()连接方式。
消防控制室的设置应符合哪些规定?
旅游团抵达后,地陪应做好()等几方面的工作。
列举5个以上(含古代)安徽省著名水利工程。
张某,16岁,因家里人忙于外出工作,一直和爷爷奶奶住,是标准的留守儿童。因不愿意学习也没人及时督促教育,辍学在家。一年前,因为打游戏成瘾花光了父母给的每个月生活费,于是在一个夜晚抢劫了一个初中生。案发后的第二天,家人带其来当地派出所自首,法院考虑到张某认罪
当某市场中只存在苹果和梨两种商品,苹果价格上升时人们会减少苹果的购买量而增加梨的购买。此时,苹果与梨这两种商品之间存在()。
唐朝初年,“控弦数十万,霸有西域”的少数民族政权是()。
A、HelenKeller’sunusuallife.B、HelenKeller’sunhappychildhood.C、HelenKeller’shelpfulteacher.D、HelenKeller’sserioussi
最新回复
(
0
)