共用题干 第三篇Listening Device Provides Early Landslide(山崩;地滑;塌方)WarningA device t...

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问题 共用题干 第三篇

Listening Device Provides Early Landslide(山崩;地滑;塌方)Warning

A device that provides early warning of a landslide by monitoring vibrations(振动)in soil is being tested
by UK researchers,The device could save thousands of lives each year by warning when an area should be
evacuated(疏散,撤走),the scientists say. Such natural disasters are common in countries that experience
sudden, heavy rainfall (降雨,降雨量), and can also be triggered by earthquakes and even water
erosion(腐蚀,侵蚀).
Landslides start when a few particles of soil or rock within a slope start to move,hut the early stages can
be hard to spot.Following this initial movement,"slopes can become unstable in a matter of hours or
minutes,"says Nell Dixon at Southborough University,UK. He says。warning system that monitors this
movement"might be enough to evacuate a block of flats or clear a road,and save lives".
The most common way to monitor a slope for signs of an imminent(即将发生的) landslide is to watch
for changes in its shape. Surveyors can do this by measuring aside directly,or sensors(传感器)sunk into
boreholes(钻孔,井眼)or fixed above ground can be used to monitor the shape of a slope. Slopes can,
however,change shape without triggering a landslide,so either method is prone to causing false alarms.Now
Dixon's team has developed a device that listens for the vibrations caused when particles begin moving
within a slope.
The device takes the form of a steel pipe dropped into a borehole in a slope.The borehole is filled in
with gravel(砾,沙砾,砾石)around the pipe to help transmit high-frequency vibrations generated by particles
within the slope.These vibrations pass up the tube and are picked up by a sensor on the surface.Software
analyses the vibration signal to determine whether a landslide may be imminent.
The device is currently being tested in a 6-metre-tall artificial clay embankment(堤岸)in Newcastle,
UK.Early results suggest it should provide fewer false positives than existing systems.Once it has been
carefully and thoroughly tested,the device could be used to create a complete early-warning system for
dangerous slopes.
"Locations with a significant risk of landslides could definitely benefit from a machine like this,"says
Adam Poulter,an expert at the British Red Ci?oss,"As long as it doesn't cost too much."But,Poulter adds
that an early-warning system may not be enough on its own."You need to have the human communication."
he says,"Making systems that get warnings to those who need them can be difficult."
选项 According to the context,what does the word"positives"in the fifth paragraph mean? A:Positive electric charges. B:Evidences. C:Warnings. D:Predictions.
答案 B
解析 短文第一段第一句提到了山体滑坡,此处的自然灾害指的是上文的山体滑坡,故选D。
短文第二段第一、二句提到“滑坡开始时,一个山坡上的土壤或岩石粒子移动,但初期 可能很难辨认。然后山坡在数小时或数分钟内可能变得不稳固”,故选D。
短文第三段倒数第二句提到“……任何一种方法(普通方法)都可能产生错误预警”,故 选C。
根据短文第四段第二句可知,地上凿出的洞而非该装置是用砾石填充的,A项的叙述不 正确。故选A
此句意为“早期的结果表明它应该提供比现有系统更少的不实证据”,故选B。 positive 意为“确凿的证据”。第5部分:补全短文

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