中文说明：Level Set方法的基本思想是将平面闭合曲线隐含地表达为二维曲面函数的水平集,即具有相同函数值的点集,通过Level Set函数曲面的进化隐含地求解曲线的运动.尽管这种转化使得问题在形式上变得复杂,但在问题的求解上带来很多优点,其最大的优点在于曲线的拓扑变化能够得到很自然的处理,而且可以获得唯一的满足熵条件的弱解.DRLSE算法是李纯明教授提出
English Description：
The basic idea of level set method is to implicitly express the plane closed curve as the level set of two-dimensional surface function, that is, the point set with the same function value, and implicitly solve the motion of the curve through the evolution of level set function surface, The greatest advantage of drlse is that the topological changes of curves can be handled naturally, and the only weak solution satisfying the entropy condition can be obtained