Before revision:  This paper aims at working out the optimal retention ratio, dividend payout level, explicit value function of the insurance company under bankrupt probability constraint by stochastic analysis, PDE methods and variational inequality approach , getting a risk-based capital standard to ensure the capital requirement of can cover the total given risk by numerical analysis , and giving reasonable economic interpretation for the results.
After revision:  This paper aims at working out the optimal control policy as well as optimal return function for the company under bankrupt probability constraint by stochastic analysis, PDE methods and variational inequality approach , getting a risk-based capital standard to ensure the capital requirement of can cover the total given risk by numerical analysis , and giving reasonable economic interpretation for the results.