Dynamic vs Algebraic

• Dynamic system has “memory”, output depends on present and past
  • Includes diff and/or integral operators with initial conditions
  • Cap and or inducer
• Algebraic
  • No calculus operators
  • Output depends only on input

Time Invariant vs Time-Varying

Continuous vs Discrete time

Linear vs Non-Linear

Deterministic vs Stochastic

• Deterministic
  • Output fully determined by parameter inputs
• Stochastic
  • Include randomness
    • Noise/Disturbance
  • Same inputs can lead to different outputs

Lumped vs Distributed parameters

• Lumped
  • Only one independent variable (time $t$)
  • Typical for electrical systems
  • $x(t)$
  • Ordinary differential equations
• Distributed
  • Several independent variables
    • time, pressure, temperature
  • Typical for chemical processes and process control -$x(t, P, T)$
  • Differential partial equations

Causal vs Non-Causal

• Causal
  • Output depends only on current and past values
• Non-Causal
  • Output depends on future inputs

SISO vs MIMO

• Single Input/Single Output
• Multiple Input/Multiple Output