^{-(\frac{\gamma_{t,0}}{\gamma_{t,d}}\lambda_{0i} + \lambda_{0i}) \gamma}, & \text{if } \gamma < \gamma_{t,d}, \\ 0-e^{-(\lambda_{0i}\gamma_{t,0} + \lambda_{0i}\gamma) },& \text{if } \gamma \geq \gamma_{t,