The image will be distorted when we take the object's picture with CCD at long range because of atmosphere turbulence. We can't availably recognize and monitor long distance object for this reason.

用CCD（电荷耦合器件）拍摄远距离目标时，大气湍流使得图像发生畸变，导致CCD无法有效的用于远距离目标的识别与监控。

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Humans are wired to calculate the distance of an object by using the vertical Angle between its top and bottom.

人类通常是通过一个物体上下间的的垂直角度来计算与它相隔的距离。

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Looking through the rifle's telescopic sight, the gunman then estimates the distance from this object to the target.

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The scanner itself consists of a digital camera with an on-board laser that determines the distance to the object, although it also apparently requires that targets be placed around the scene to properly scan the object -- or person, as the case may be.

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The longer the distance between the two points in physical space, the more effort it takes to get an object from point A to point B.

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