在平行于放置被摄物体的位置上把有距离标尺的测试图表放置于一个斜面上。

Next to the parallel target, a patterned chart with a distance scale is placed on an incline.

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也可以把这种坐标，看成是空间中的极坐标，它其实使用了，距离原点的距离，然后用角度这种标尺，来确定了方向。

So, in a way, you can think of these as a space analog of polar coordinates because you just use distance to the origin, and then you have to use angles to determine in which direction you're going.

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划线后检查吃水标尺至平板龙骨之间的距离。

Inspection distance between draught marks and keel plate after marking out.

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