最高阶导数线性地出现的那种方程是准线性方程.A quasilinear equation is one in which the highest - order derivative appears linearly.这种 “ 导数边界条件 ” 的规定描述于 3-5 节中.The specification of such " derivative boundary conditions " is described in Sectio...
他送给女友一枚镶着蓝宝石的订婚戒指。He gave his girlfriend a sapphire engagement ring.现在让我们考虑象钻石和蓝宝石这样的晶体.Now let us consider crystals such as diamond or sapphire.现在让我们考虑象金刚石和蓝宝石这样的晶体.Now let us consider crystals such as diamond or sopphi...