He suggests using electric motors or shape-memory materials to repeatedly flick the end of a flexible, wedge-shaped wing, creating a wave that ripples backwards and generates forward thrust.
Indeed, the thrust of the entire meeting was to urge a realignment of the global order imposed after the end of the second world war and the subsequent ascendancy of the United States.
实际上，整个会议的实质就是敦促二战后以美国为主导的全球秩序进行重新洗牌。
3
With all cylindrical roller thrust bearings, increased sliding friction can occur on the end of the cylindrical rollers.