The " bite test " was to check if the coin was gold.

“咬测试”是检查硬币是否是黄金。

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In the paper, the method of test about OE-PCB was reviewed. Including mainly Refractive Index, Optical Propagation Loss, Surface Roughness, Eye Pattern, Bite Error Rate test and Environment Impact.

文章介绍了印制光-电路板的测试方法，主要包括光波导的折射率测试、光传输损失测试、表面粗糙度测试、眼图测试、误码率测试、环境测试。

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Money handlers would bite down on coins to test their authenticity, said David W. Lange of Numismatic Guaranty Corporation.

CNN: Why Olympians bite their medals