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2015考研英语复习正是强化复习阶段,考研英语阅读在考研英语中占了40分,所以考研英语阅读是英语科目中重要的一项。新东方名师范猛老师曾建议过考研生需要坚持每天泛读10-15分钟的英文原刊。强烈推荐了杂志《经济学人》.杂志中的文章也是考研英语的主要材料来源.希望考研考生认真阅读,快速提高考研英语阅读水平。
Flipping roaches
非常蟑螂
How cockroaches vanish.
蟑螂是怎么消失不见的?
ANYONE who has tried to swat a cockroach willknow those insects' strange ability, in the heat ofpursuit, to disappear. Robert Full and his colleaguesat the University of California, Berkeley, have now worked out how they do this-and taught aminiature robot to copy the feat.
只要打过蟑螂的都知道它们特殊的本领——往往在追赶最激烈的时候突然消失不见了。加州大学伯克利分校的Robert Full和他的同事现在已明白它们是怎么做到的,并用一个微型机器人模拟了这个过程。
Dr Full had been using high-speed photography to study how cockroaches employ theirantennae to sense and cross gaps. When the researchers made the gaps wider, they saw theanimals flipping back underneath the ledge at the edge of the gap, rather than jumping acrossthe empty space. As they report in the Public Library of Science, cockroaches running towardsa gap suddenly grip the edge with the hooklike claws on their rear legs and swing 180° toland firmly underneath the ledge, upside down. They can pull off this stunt in a fifth of asecond-so fast that the animals' bodies are subject to between three and five times the forceof gravity, and also so fast that the movement is invisible to the human eye.
Full博士运用了高速摄影技术来研究蟑螂是如何使触须去感知和穿过缝隙。当研究者把缝隙扩宽,发现蟑螂直接在缝隙边缘翻转下去,而不是跳过缝隙,正如《科学公共图书馆》所报道的那样,蟑螂先迅速冲向缝隙,然后用后腿上的钩状爪子抓住边缘,顺势摆动180°,头朝下牢牢抓住平板底部。它们能在0.2秒内完成这项绝技,这么快的速度蟑螂的身体要承受3到5倍的重力加速度,也正是由于这么快的移动速度才让人类难以发现。
Dr Full and his colleagues have since identified similar behaviour in other animals withhooklike toes that are good at escaping pursuit: geckos, for example. They have also teamedup with members of Berkeley's robotics laboratory to program a small six-legged robot thathas strips of Velcro attached to its rear legs to do the same trick. Such a robot could be fittedwith a camera and used as a surveillance device. Some people, though, might prefer it to befitted with a miniature machinegun and used as a UCPV (unmanned cockroach pursuitvehicle).
Full博士和同事后来又发现了其他具有类似特性的生物,它们同样具有钩状的脚趾并擅长逃离追杀,比如壁虎。他们也与伯克利分校机器人实验室合作,设计了一只小型六脚机器人,然后把魔术贴粘在机器人的后腿上,最后成功完成了类似动作。这种机器人可以用来装配相机作为监视装置,尽管如此,一些人更希望它装配微型机枪变成自动蟑螂捕杀器。
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