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Blind people usually possess one advantage over other people who can see: their sense of hearing is far more acute. Sounds which most others would miss can carry a great deal of information to a sightless person. For instance, teams of blind children can enjoy fast-moving games of soccer with a bell inside the ball and a new hand-held ultrasonic device to guide them. And that sound-location system could help to build up an even more complete sound picture of a blind person’s surroundings. Bats, whose sight is poor, use a sound-location system to help them avoid obstacles in the dark. They send out pulses of sound waves, pitched at 50,000 cycles per second, far above the limits of the human ear, which can hear sounds up to frequencies of about 20,000 cycles per second. As the echoes bounce back off obstacles such as trees and walls, the bats are able to take appropriate action. The first steps to help blind people to see with sound are based on exactly the same principle. The sound is emitted by an ultrasonic torch, shaped like a double-barreled version of a normal electric torch. It works in a similar Way to a sonar u nit on a warship or submarine. The unit’s transmitter sends out pulses of ultrasonic waves at the same frequency as the bat, and the receiver picks up the returning echoes. Because these are still above the frequency at which the human ear can pick them up, the echoes are filtered through circuits which turn them into clearly audible ’ bleeps’ before passing them into headphones. This means that a person holding the torch can point it ahead of him and ‘scan’the area for obstacles over a range of about 25 ft. ff there are no return echoes coming through the headphones, then there is nothing in the way. If echoes do come back, then the closer the obstruction, the faster the succession of bleeps and the deeper the pitch of each bleep. With practice the torch could help a blind person to lead a more normal life -- without needing a constant companion to guide him. Experienced operators of the torch system claim they can distinguish grass from bushes, trees, pests and curbstones. But before blind people can be helped to feel really independent, the system needs to be more streamlined. At pres ent, the experimental ultrasonic torch requires a shoulder bag to carry the batteries, cables for the power supplies and earphones, in addition to the torch itself. But miniaturization of electronic equipment is making such rapid progress that it should not be long before the whole set-up can be reproduced in a form small enough to fit into a pair of spectacles. The transmitter and power supplies, with all the circuitry, would be packed into the bridge-piece above the nose. The sending and receiving sensors would be in the ’ lenses’. And the filtered bleeps would be passed on to the wearer through the earpieces, as with present-day hearing-aid spectacles. This would mean that scanning one’s surroundings would become instinctive. The wearer would face in the direction he wanted to check, and lift or lower his head just as a sighted person would. The returning echoes the receiver picks up are ______.
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Blind people usually possess one advantage over other people who can see: their sense of hearing is far more acute. Sounds which most others would miss can carry a great deal of information to a sightless person. For instance, teams of blind children can enjoy fast-moving games of soccer with a bell inside the ball and a new hand-held ultrasonic device to guide them. And that sound-location system could help to build up an even more complete sound picture of a blind person’s surroundings. Bats, whose sight is poor, use a sound-location system to help them avoid obstacles in the dark. They send out pulses of sound waves, pitched at 50,000 cycles per second, far above the limits of the human ear, which can hear sounds up to frequencies of about 20,000 cycles per second. As the echoes bounce back off obstacles such as trees and walls, the bats are able to take appropriate action. The first steps to help blind people to see with sound are based on exactly the same principle. The sound is emitted by an ultrasonic torch, shaped like a double-barreled version of a normal electric torch. It works in a similar Way to a sonar u nit on a warship or submarine. The unit’s transmitter sends out pulses of ultrasonic waves at the same frequency as the bat, and the receiver picks up the returning echoes. Because these are still above the frequency at which the human ear can pick them up, the echoes are filtered through circuits which turn them into clearly audible ’ bleeps’ before passing them into headphones. This means that a person holding the torch can point it ahead of him and ‘scan’the area for obstacles over a range of about 25 ft. ff there are no return echoes coming through the headphones, then there is nothing in the way. If echoes do come back, then the closer the obstruction, the faster the succession of bleeps and the deeper the pitch of each bleep. With practice the torch could help a blind person to lead a more normal life -- without needing a constant companion to guide him. Experienced operators of the torch system claim they can distinguish grass from bushes, trees, pests and curbstones. But before blind people can be helped to feel really independent, the system needs to be more streamlined. At pres ent, the experimental ultrasonic torch requires a shoulder bag to carry the batteries, cables for the power supplies and earphones, in addition to the torch itself. But miniaturization of electronic equipment is making such rapid progress that it should not be long before the whole set-up can be reproduced in a form small enough to fit into a pair of spectacles. The transmitter and power supplies, with all the circuitry, would be packed into the bridge-piece above the nose. The sending and receiving sensors would be in the ’ lenses’. And the filtered bleeps would be passed on to the wearer through the earpieces, as with present-day hearing-aid spectacles. This would mean that scanning one’s surroundings would become instinctive. The wearer would face in the direction he wanted to check, and lift or lower his head just as a sighted person would. Which of the following is NOT true about the ultrasonic torch
In recent decades child specialists have tried more and more to help parents with their children’s school behavior. Schools of education (31) tended to emphasize subject matter (32) what the children are being taught, but attention increasingly is being paid to the children themselves. One area (33) emphasized is the matter of a (34) developmental or "maturity" level--that is, the child’s (35) of readiness for starting school. Research demonstrated that a major (36) of children who fail in school (37) primarily because of their immaturity and their unreadiness for the work of the (38) that law designates: age five for kindergarten, age six for first grade. Common sense (39) us that not all five-year-olds have reached (40) average level of performance expected (41) age five. Thus many five-year-olds fail in kindergarten and six-year-olds fail in first grade (42) because of a "learning disability" or "attention deficit disorder" but simply because (43) are in a too-advanced grade. Experience has shown that the number of (44) learners can be substantially reduced by a policy of (45) every child’s readiness--that is, (46) level before beginning school. This concept has (47) widely. Many school systems now routinely provide not only readiness testing but also extra grade (48) : pre-kindergarten or "developmental" kindergarten for a year (49) full kindergarten; and pre-first grade for six-year-olds not fully (50) for first grade.
American hopes that pressure from the US will force Japan to suddenly dismantle its trade barriers are almost certain to evaporate in disappointment①. The fact is that Washington faces an obstacle far more formidable than a few power brokers in Tokyo’s government offices. It’s not in line with the centuries-old, deep-ingrained Japanese customs. To move the Japanese government, Washington government must move an entire nation. So far the US has had only limited success despite congressional threats to retaliate. In an April 9 nationwide broadcast, Prime Minister Yasuhiro Nakasone urged the Japanese to buy more imported goods and unveiled a long-awaited three-year plan to ease import restrictions. But this program was far short of what Washington hoped to see. White House Chief of Staff Donald Regan said the Japanese offered "few new or immediate measures." While the plan did promise fewer shackles on imports of telecommunications gear, medicine and medical equipment, it offered no relief for American forest products—which are among the most contentious trade issues. Nakasone gives every sign of being secure in his desire to reduce a Japanese surplus in trade with the US that hit 36.8 billion dollars in 1984 and could soon top billion. Yet to rely on any Japanese political leader, no matter how popular he is at home, to reverse trade policies is to underestimate the culture and traditions that weigh heavily against a breakthrough②. Big business and dozens of anonymous bureaucrats have as much power as Japan’s top elected leaders. "The whole concept that we can turn this around right now is obviously ridiculous," says an American trader who has lived and worked here since 1952. "The vested interests are being shaken and slowly moved, but at a pace too slow for the eye to follow." That view is echoed by a US diplomat closely involved in the efforts to open the Japanese market to American goods, Washington’s main solution to the ballooning trade ambulance. "Japan is a relationship society rather than a transactional one," he says. "You cannot alter that kind of a system with a television speech or a few general proposals, no matter how well-intended they are." Beyond specific tariffs or other official barriers to imports, experts here say that the US faces these obstacles. Nearly total domination of the Japanese market by a few dozen giant conglomerates that strongly op pose even token competition—be it from abroad or emerging domestic firms. An elite, thickly layered bureaucracy that historically has drafted laws and regulations as well as enforced them, and both of these powers would be threatened by trade reforms. A longtime relationship between business and government that critics say fosters collusion and hinders foreign entry into domestic markets③. According to the text, the main factor working against any immediate entry into Japanese market is ______.
American hopes that pressure from the US will force Japan to suddenly dismantle its trade barriers are almost certain to evaporate in disappointment①. The fact is that Washington faces an obstacle far more formidable than a few power brokers in Tokyo’s government offices. It’s not in line with the centuries-old, deep-ingrained Japanese customs. To move the Japanese government, Washington government must move an entire nation. So far the US has had only limited success despite congressional threats to retaliate. In an April 9 nationwide broadcast, Prime Minister Yasuhiro Nakasone urged the Japanese to buy more imported goods and unveiled a long-awaited three-year plan to ease import restrictions. But this program was far short of what Washington hoped to see. White House Chief of Staff Donald Regan said the Japanese offered "few new or immediate measures." While the plan did promise fewer shackles on imports of telecommunications gear, medicine and medical equipment, it offered no relief for American forest products—which are among the most contentious trade issues. Nakasone gives every sign of being secure in his desire to reduce a Japanese surplus in trade with the US that hit 36.8 billion dollars in 1984 and could soon top billion. Yet to rely on any Japanese political leader, no matter how popular he is at home, to reverse trade policies is to underestimate the culture and traditions that weigh heavily against a breakthrough②. Big business and dozens of anonymous bureaucrats have as much power as Japan’s top elected leaders. "The whole concept that we can turn this around right now is obviously ridiculous," says an American trader who has lived and worked here since 1952. "The vested interests are being shaken and slowly moved, but at a pace too slow for the eye to follow." That view is echoed by a US diplomat closely involved in the efforts to open the Japanese market to American goods, Washington’s main solution to the ballooning trade ambulance. "Japan is a relationship society rather than a transactional one," he says. "You cannot alter that kind of a system with a television speech or a few general proposals, no matter how well-intended they are." Beyond specific tariffs or other official barriers to imports, experts here say that the US faces these obstacles. Nearly total domination of the Japanese market by a few dozen giant conglomerates that strongly op pose even token competition—be it from abroad or emerging domestic firms. An elite, thickly layered bureaucracy that historically has drafted laws and regulations as well as enforced them, and both of these powers would be threatened by trade reforms. A longtime relationship between business and government that critics say fosters collusion and hinders foreign entry into domestic markets③. Which of the following is NOT mentioned as one of the trade obstacles in the text
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