Identification of a Nonlinear Cell Cycle System with Linear Models, Report no. LiTH-ISY-R-2690

A mathematical model by Chen et al. representing the cell cycle of the budding yeast cell (Saccharomyces cerevisiae) is used to simulate levels of 13 different cell biological variables. By using a linear systems approach on the generated data the goal is to identify the original equations of the mathematical model. Since this model is described by a nonlinear system the linear systems approach only gives correct estimations of the linear parts of the system, with one exception. A main issue thus becomes to identify which data that belongs to the linear equations and which does not. This problem is solved using two local linear models on different time intervals. Parameter estimations of coefficients from linear and time invariant equations should be the same over all time intervals.