Simulation and modeling - Old Questions

Discrete system is one in which the state variables changes only at a discrete set of time. For example: banking system in which no of customers (state variable) changes only when a customer arrives or service provided to customer i.e. customer depart form system.

Continuous system is one in which the state variables change continuously over time. For example, the head of the water behind a dam. During and for some time after a rainstorm, water flows into the lake behind the dam. Water is drawn from the dam for flood control and to make electricity. Evaporation also decreases the water level.

--> Discrete model is appropriate for system having discrete state and changes at particular time point and remains in that state for some time where as Continuous model is a appropriate for system with a continuous state that changes continuously over time.

--> Most discrete time system represents how discrete signals are transformed via difference equations where as Most continuous time system represent how continuous signals are transferred via differential equations.

--> A discrete simulation model is not always used to model a discrete system, nor is a continuous model always used to model a continuous system.