Partial differential-algebraic equation PDAE

Limiting the discussion to the use of first-principle models, the behavior of the desired equipment is represented by either (i) a set of algebraic equations or (ii) a system of ordinary differential equations (ODEs), or DAEs, or (iii) partial differential equation (PDE) and partial differential-algebraic equation (PDAE), including... 

AE for algebraic equations, ODE for ordinary differential equations, ODAE for ordinary differential anti algebraic equations, and PDAE for partial differential and algebraic equations. 

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