The proposed Linear Matrix Inequality (LMI) conditions can be extended to handle more general nonlinear systems by incorporating time-varying or uncertain parameters through the concept of Linear Parameter Varying (LPV) systems. In LPV systems, the dynamics of the system are allowed to vary with certain parameters, which can capture the time-varying or uncertain nature of the system. By formulating the observer design problem in the LPV framework, the LMI conditions can be adapted to account for these variations. This extension allows for a more robust observer design that can accommodate a wider range of system behaviors.