Experimental results show that the slow cesium atomic clock time a very small unit.

结果实验表明铯原子钟慢了很小的一个时间单位。

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Because the number of potential customers for such experimental sensors is small, the firms manufacturing them have to charge a high price per unit just to cover the fixed costs of designing the product, setting up the factory, and so forth.

FORBES: High Sensor Costs Won't Stand in the Way of the Self-Driving Future