单选题

Sonic Device

The other day, Dr. Robert Smith, who is blind, took a remarkable stroll through the campus of the University of California at Santa Barbara. As Dr. Smith walked along the campus, places and impediments (障碍物) in his path seemed to call out their names to him, "library here, library here", "bench here, bench here".
Dr. Smith was testing a prototype(样机) navigation system for the blind that announced the surrounding objects through stereo headphones that were mounted to a computer in his back-pack (背包), creating virtual reality landscape(仿真景象). The information came not from some miniature radar but from the signals broadcast by the military"s network of global positioning satellites(全球定位卫星). One day, its developers hope, miniaturized(小型化) versions of this navigation device, which now weighs 28 pounds, will help the blind navigate unfamiliar neighborhoods.
"With this system you do not need to know a thing in advance about where you are going," said Dr. Roberta Klatzky, a psychologist at Carnegie Mellon University who is working with Dr. Smith to develop the navigating device. Dr. Michael Oberdor of the National Eye Institute said, "A blind person could walk down the street and know not just that he was at 80th and Broadway, but what stores are around, and that Zabar"s delicatessen(熟食店) was up ahead. This navigation system tells you not just where there are obstacles, but your overall location geographically." It lets blind users construct a mental map of new surroundings and learn their way around.
The navigation system uses signals from a computerized map to create a "virtual acoustic display (仿真声音显示)." This is a talking map in which large objects seem to announce themselves in the headphones with the precise timing and loudness that would be the case if the objects were actually making a sound. This allows the blind person to sense immediately his or her distance or direction, and use that information for guidance While no one knows whether it is because blind people tend to develop a sharper sense of hearing. Those who have tried the system say that they quickly adapt to locating an object through the sounds. "One of the crucial features of this system is that it takes advantage of sensory psychophysics(感官心理物理学) how the brain interprets signals from outside to make a map of your surroundings so you can navigate," Dr. Oberdor said.

单选题 Thanks to the help of this sonic device, blind people can hear obstacles in the way speaking out their names.

【正确答案】 B

【答案解析】[解析] 题意：多亏了发声装置，盲人可以听到路上的障碍物并说出它们的名字。
关键词是“obstacles(障碍物)”。依据此关键词，可在文中第一、二段找到相关叙述：“places and impediments(障碍物)in his path seemed to call out their names to him...Dr．Smith was testing a prototype(样机)navigation system for the blind that announced the surrounding objects through stereo headphones”，由此可推断发声的不是物体本身，而是这个可以发声的装置，故此题说法为“错误”的。

单选题 Dr. Smith hopes to make this device smaller so as to help the blind navigate unfamiliar places.

单选题 Although this device will be useful, most of the blind may not afford it.

单选题 According to Dr. Oberdor, this device can lead the blind people to the exact place he/she wants to go.

【正确答案】 A

【答案解析】[解析] 题意：根据奥博多博士研究，这个装置可以准确地带盲人去他/她想去的地方。
关键词是lead the blind people to the exact place。依据此关键词，可在文中第三段找到相关叙述：
“A blind person could walk down the street and know not just he was at 80th and Braodway, but what stores are around，and that Zabar"s delicatessen(熟食店)was up ahead.”作者通过运用实际例子说明这个机器的精确度，故此题说法为“正确”的。

单选题 The blind can hear better than ordinary people.

单选题 Scientists intend to reduce the weight of this device to ten pound.

【正确答案】 C

【答案解析】[解析] 题意：科学家们企图把这个装置的重量降到10英镑。
关键词是weight。依据此关键词，可在文中第二段找到相关叙述：“its developers hope，miniaturized(小型化的)versions of this navigation devices, which now weighs twenty-eight pounds”，由此可见，文章只提到希望把28英镑的发声装置改造成微型版本的机器，但并没有提到具体降到多重，故此题说法为“来提及”的。