When the measured strain changes, the stick does not change in length, but the FBG does.

当被测应变变化时，光纤光栅长度变化而棒长不变；

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If a bar is subjected to an axial load, and hence a stress, the bar will change in length.

如果一家酒吧受到轴向负载，因此压力，酒吧将改变长度。

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What excites ophthalmologists most, and what every lens-making company wants to achieve, is an “accommodating” lens that can change its focal length in the same way that a natural lens does.

最让眼科学家兴奋的，而且每一家人工晶体制造公司都想获得的，是一种“善于适应新环境的”晶体，能像天然的晶体一样改变它的焦距。

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Unlike their athletes (who still face a transferring penalty for breaching their letter-of-intent if their coach leaves), coaches have no waiting period when switching schools and until this change in the length of a scholarship, schools had no waiting period to replace a player dismissed under a non-renewed scholarship.

FORBES: National Letter of Indenture: Why College Athletes are Similar to Indentured Servants of Colonial Times