We were offered to be able to shoot inside the White Sands missile range, but they are doing periodic bomb tests.

我们本来获得了在白沙导弹靶场内部的拍摄许可，但他们会定期进行炸弹试爆。

The discs were subjected to periodic compression tests to compare their performance to natural ones.

这些圆盘定期进行压缩测试，以将其性能与天然圆盘进行比较。