ABSTRACT
JAGAN: “dk3189_c004” — 2006/3/13 — 11:47 — page 265 — #1
Many systems in nature, including biological systems, are dynamical in the sense that they are acted upon by external inputs, have internal memory, and behave in certain ways that can be captured by the notion of the development of activities through time. The name system was formalized in the early 1900s by Whitehead (1953) and von Bertalanffy (1968). A system is viewed as an entity distinct from its environment, whose interactions with the environment can be characterized through input and output signals. An intuitive feel for dynamical systems is provided by Luenberger (1979), which has many excellent examples. The dynamics of a nonlinear system is expressed in state-space form as a nonlinear difference or differential equation (see Equation 2.1). This state equation can describe a variety of dynamical behaviors, including mechanical and electrical systems, earth atmosphere dynamics, planetary orbital dynamics, aircraft dynamics, population growth dynamics, and chaotic behavior.
