Why can we see part of the plastic ball?

为什么我们能看见塑料球的一部分？

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The orthogonal experiment design method was applied to study the relationships between solder joint process parameters and reliability of plastic ball grid array (PBGA) component.

基于正交试验设计法对塑封球栅阵列(PBGA)器件焊点工艺参数与可靠性关系进行了研究。

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It involves a giant plastic ball, which has two skins - one inside the other with air pumped in between.

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The first time I saw Cuponk, the game that requires players to bounce a ping pong ball into a plastic cup, all I could think of was drunken college parties and matches of Beirut, the game otherwise known as known as Beer Pong.

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"If you think that it's going to rain the day before, you need to high-tail yourself down to Home Depot and get a bunch of plastic, and do just like they do at the ball parks, " said Reeves.

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