题干

为什么人的肺不是一个大的囊泡,而是由很多小的肺泡构成的呢?用下列切萝卜的模拟实验可帮助理解:如图,将一大块萝卜不断等分,测量切块的边长,计算切块的表面积并求和。

通过“切块表面积之和”这一数据的变化可以说明,由于许多肺泡的存在增大了肺的表面积,从而提高____的效率。

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    Claude Sammut,a professor of computer science and engineering at the University of New South Wales in Australia,said it would soon be possible for robots to defeat the stars of the future.

    For many years,Mr Sammut has been a member of a project called RoboCup,where robots have been programmed to learn how to play football and compete against others in a football match.

    As he explains,the robots are having difficulty in learning how to control the ball and move the ball on their own,but he is still full of confidence that one day in the future they will show the same skills as Wayne Rooney,who is one of the best football players in the world.

    Mr.Sammut also said,"In 1968,John McCarthy and Donald Michie made a bet with David Levy,who was then the chess champion in Scotland,that within 10 years a computer program would be able to beat him.It took a little bit longer than 10 years (nearly 30 years) but eventually such programs came into being."

    "In the same spirit of a grand challenge,RoboCup aims to develop a team of robots that can defeat the world soccer champion team by the year 2050.To achieve this,or come even closer to the ambition,the robots will have to be able to sense and act in completely unstructured environments.This will require major advances in perception(感知),decision making,learning,and cooperative behaviors.Considering robots are integrated hardware and software systems,great advances will also be needed in sensors(传感器),energy storage,and materials."