名义尺寸 meaning in Chinese

nominal dimensions
nominal size
specifiedsize

Especially for ship and ocean - platform structure , there are a lot of stochastic factors affecting their design , for example , wave , tidewater and wind which act on the ship surface are indeterminate ; material data and dimension data provided may be not completely consistent with that of real structure ; some hypothesis , for convenience and simplification , make the calculation model is not the same as the real structure
特别对船舶与海洋平台等结构，影响结构设计的随机因素很多，例如作用在船舶上的波浪、潮水和风荷载都是不确定的；结构中用的材料物理性能数据可能与提供的有所差异；名义尺寸也可能与实际结构不完全一致；计算中引进的一些假设，也会使计算模式与实际情况有所偏离等等。