a prior estimate meaning in English

事前估计
先验估计

There are three sections in this paper . the first section : we consider the initial boundary value problem on half line and bounded interval , with kato ' s method for abstract quasi - linear evolution equations and a prior estimates of . solution , we get the existence of global smooth solution and the blow - up of solution in finite time under some conditions
第一部分：考虑了camassa ? holm方程在半无界和有界区域上的初边值问题，用kato关于拟线性演化方程的初值问题的理论及先验估计的方法，证明了整体解的存在性，及在一定条件下，解在有限时间内的blow ? up 。