What might driving on an automated highway be like The answer depends on what kind of system is ultimately adopted. Two distinct types are on the drawing board. The first is a special purpose lane system, in which certain lanes are reserved for automated vehicles. The second is a mixed traffic system: fully automated vehicles would share the road with partially automated or manual driven cars. A special purpose lane system would require more extensive physical modifications to existing highways, but it promises the greatest gains in freeway (高速公路) capacity.Under either scheme, the driver would specify the desired destination, furnishing this information to a computer in the car at the beginning of the trip or perhaps just before reaching the automated highway. If a mixed traffic system way was in place, automated driving could begin whenever the driver was on suitably equipped roads. If special purpose lanes were available, the car could enter them and join existing traffic in two different ways. One method would use a special onramp (入口引道). As the driver approached the point of entry for the highway, devices installed on the roadside would electronically check the vehicle to determine its destination and to ascertain that it had the proper automation equipment in good working order. Assuming it passed such tests, the driver would then be guided through a gate and toward an automated lane. In this case, the transition from manual to automated control would take place on the entrance ramp. An alternative technique could employ conventional lanes, which would be shared by automated and regular vehicles. The driver would steer onto the highway and move in normal fashion to a "transition" lane. The vehicle would then shift under computer control onto a lane reserved for automated traffic. (The limitation of these lanes to automated traffic would, presumably, be well respected, because all trespassers (非法进入者) could be swiftly identified by authorities. )Either approach to joining a lane of automated traffic would harmonize the movement of newly entering vehicles with those already traveling. Automatic control here should allow for smooth merging without the usual uncertainties and potential for accidents. And once a vehicle had settled into automated travel, the driver would be free to release the wheel, open the morning paper or just relax. We know from the passage that a car can enter a special purpose lane ______.
A. by smoothly merging with cars on the conventional lane
B. by way of a ramp with electronic control devices
C. through a specially guarded gate
D. after all trespassers are identified and removed
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Nuclear power"s danger to health, safety, and even life itself can be summed up in one word: radiation. Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can"t be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can"t sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.At very high levels, radiation can kill an animal or human being outright by killing masses of cell in vital organs. But even the lowest levels can do serious damage. There is no level of radiation that is completely safe. If the radiation does not hit anything important, the damage may not besignificant.This is the case when only a few cells are hit, and if they are killed outright. Your body will replace the dead cells with healthy ones. But if the few cells arc only damaged, and if they reproduce themselves, you may be in trouble. They reproduce themselves in a deformed way. They can grow into cancer. Sometimes this does not show up for many years.This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated and feel fine, then die of cancer five, ten, or twenty years later as a result. Or a child can be born weak or liable to serious illness as a result of radiation absorbed by its grandparents. It is not too careful to prevent from the radiation. Radiation can hurt us. We must know the truth. Which of the following can be best inferred from the passage
A. The protection from radiation cannot be over-emphasized
B. The mystery about radiation remains unsolved
Cancer is mainly caused by radiation
D. Radiation can hurt those who are not aware of its danger
Nuclear power"s danger to health, safety, and even life itself can be summed up in one word: radiation. Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can"t be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can"t sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.At very high levels, radiation can kill an animal or human being outright by killing masses of cell in vital organs. But even the lowest levels can do serious damage. There is no level of radiation that is completely safe. If the radiation does not hit anything important, the damage may not besignificant.This is the case when only a few cells are hit, and if they are killed outright. Your body will replace the dead cells with healthy ones. But if the few cells arc only damaged, and if they reproduce themselves, you may be in trouble. They reproduce themselves in a deformed way. They can grow into cancer. Sometimes this does not show up for many years.This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated and feel fine, then die of cancer five, ten, or twenty years later as a result. Or a child can be born weak or liable to serious illness as a result of radiation absorbed by its grandparents. It is not too careful to prevent from the radiation. Radiation can hurt us. We must know the truth. Radiation can hurt us in the way that it can ______.
A. kill a numbers of cells in main organs to cause death
B. damage cells which nay grow into cancer years later
C. affect the healthy growth of our offspring
D. All of the above
In the 1950s, the pioneers of artificial intelligence (AI) predicted that, by the end of this century, computers would be conversing with us at work and robots would be performing our housework. But powerful as computers are, they"re nowhere close to achieving anything remotely resembling these early aspirations for humanlike behavior. Never mind something as complex as conversation: the most powerful computers struggle to reliably recognize the shape of an object, the most elementary of tasks for a ten-month-old kid.A growing group of AI researchers think they know where the field went wrong. The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, step-by- step programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional computer programs. Rather than digital computers and transistors, some want to work with brain cells and proteins. The results of these early efforts are as promising as they are peculiar, and the new nature-based AI movement is slowly but surely moving to the forefront of the field.Imitating the brain"s neural (神经的) network is a huge step in the right direction, says computer scientist and biophysicist Michael Conrad, but it still misses an important aspect of natural intelligence. "People tend to treat the brain as if it were made up of color-coded transistors", he explains, "but it"s not simply a clever network of switches. There are lots of important things going on inside the brain cells themselves. " Specifically, Conrad believes that many of the brain"s capabilities stem from the pattern recognition proficiency of the individual molecules that make up each brain cell. The best way to build and artificially intelligent device, he claims, would be to build it around the same sort of molecular skills.Right now, the option that conventional computers and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow AI rebels could turn out to be the only game in town. Which of the following is closest in meaning to the phrase "the only game in town" ( Line 3, Para. 4)
A. The only approach to building an artificially intelligent computer
B. The only way for them to win a prize in artificial intelligence research
C. The only area worth studying in computer science
D. The only game they would like to play in town
In the 1950s, the pioneers of artificial intelligence (AI) predicted that, by the end of this century, computers would be conversing with us at work and robots would be performing our housework. But powerful as computers are, they"re nowhere close to achieving anything remotely resembling these early aspirations for humanlike behavior. Never mind something as complex as conversation: the most powerful computers struggle to reliably recognize the shape of an object, the most elementary of tasks for a ten-month-old kid.A growing group of AI researchers think they know where the field went wrong. The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, step-by- step programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional computer programs. Rather than digital computers and transistors, some want to work with brain cells and proteins. The results of these early efforts are as promising as they are peculiar, and the new nature-based AI movement is slowly but surely moving to the forefront of the field.Imitating the brain"s neural (神经的) network is a huge step in the right direction, says computer scientist and biophysicist Michael Conrad, but it still misses an important aspect of natural intelligence. "People tend to treat the brain as if it were made up of color-coded transistors", he explains, "but it"s not simply a clever network of switches. There are lots of important things going on inside the brain cells themselves. " Specifically, Conrad believes that many of the brain"s capabilities stem from the pattern recognition proficiency of the individual molecules that make up each brain cell. The best way to build and artificially intelligent device, he claims, would be to build it around the same sort of molecular skills.Right now, the option that conventional computers and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow AI rebels could turn out to be the only game in town. What"s the author"s opinion about the new AI movement
A. It has created a sensation among artificial intelligence researchers but will soon die out
B. It"s a breakthrough in duplicating human thought processes
C. It"s more like a peculiar game rather than a real scientific effort
D. It may prove to be in the right direction though nobody is sure of its future prospects