三次曲线
cubic curve (geometry)
二次曲线
quadratic curve (geometry); conic
二次曲面
quadric surface (geometry)
大湄公河次区域
Greater Mekong Subregion (GMS), area of economic cooperation between China and Vietnam
大湄公河次区域合作
Greater Mekong Subregion (GMS), economic cooperation program between China and Vietnam