System Models Linear VS non-linear(differential equs eg r aly+aOy=b2x+ box Principle of superposition Deterministic vs Stochastic Time-invariant VS. Time-varying Are coefficients functions of time? Continuous-time vs, Discrete-timeSystem Models n Linear vs. non-linear (differential equs) n eg, n Principle of superposition n Deterministic vs. Stochastic n Time-invariant vs. Time-varying n Are coefficients functions of time? n Continuous-time vs. Discrete-time a y a y b x b x 1  0  2  0  