在间隔时间内 meaning in English

hor interm
horis intermediis

The calculation formula of micropiv technique is the original definition of velocity : v = [ s ( t2 ) - s ( tl ) ] / ( t2 - tl ) . on the two neighboring frame of images , we search for the two small areas which have the largest correlation . by dividing their distance by their shooting interval , we got the average velocity of this small area in this interval , and then got the velocity of full flow
Piv测试原理的计算公式，是速度的原始定义： v = [ s ( t _ 2 ) - s ( t _ 1 ) ] ( t _ 2 - t _ 1 ) 。在相邻两帧图像上，找出相关度最大的两个小区域，用它们之间的距离除以两次拍摄之间的时间间隔，就得到这个小区域在间隔时间内的平均速度，进而得到整个流场的速度分布。