earn an interest of生利息
In chapter 1, we consider the surplus process of the company is modeled by a Brownian motion, and assume the surplus process does earn interest at the the constant forceρ> 0.
在第一章里面，我们考虑带Brownian运动的盈余过程，并且盈余以利率ρ＞0赚取利息。
参考来源 - 常利率风险模型关于threshold策略下的分红