The amount of time for a wave to travel a certain distance, proportional to the reciprocal of velocity, typically measured in microseconds per foot by an acoustic log and symbolized by tor DT.

波在某段距离传播的时间，与速度的倒数成正比，在声测井中，以每英尺多少毫秒来量度，用符号t或DT表示。

We cleared everything out of the way, about four or five foot along the middle of the bottom log.

我们把墙根底下那根横木的中段前面的东西搬开，清出了四五英尺宽的一块空地。

I reached for a floating log with my foot.

我伸脚去钩取一段漂浮着的木头。

With Yao Ming out for the remainder of the season with a stress fracture in his left foot, the Rockets will be asking the veteran center to log more and more minutes over the next two months.

姚明由于左脚的应力性骨折这个赛季报销了，火箭需要老兵在接下来的二个多月的时间里上场更多的时间。

It was about a foot in diameter at the big end, and he had expected to get a good saw-log, but it was so rotten as to be fit only for fuel, if for that.

大的一端直径有一英尺，原来他希望得到一些可以锯开的木料，可是树干已经腐烂得只能当柴火，这是说如果要拿它当柴火的话。