At a precise moment during one trial, the resonator might be both in its expanded and its contracted state; a single measurement forces it to "choose" which state to be in.
Influenced by the water depth of ship sea trial area, velocity measurement of deep-draft large-scale ship should be shallow-water corrected with proper method.
受实船试航水域水深的影响，对于深吃水的大型船舶航速测量结果必须采用适当的方法进行航速的浅水修正。
3
Based on a lot of spot measurement and trial work, the customary rule of slab design of the heavy plate was modified.