5) fore-and-aft draft ratio 艏吃水比6) trim difference 艏吃水差补充资料:最小辐亮度与最小辐照度(见核爆炸火球) 最小辐亮度与最小辐照度(见核爆炸火球) minimum-brightness and minimum-irradiance zuixiao fuliangdu yu zuixiaofu乙haodu最小辐亮度与最小辐照