definition for gain margin and phase margin of control system
Phase margin Phase margin and its important companion concept, gain margin, are measures of stability in closed-loop, dynamic-control systems. Phase margin indicates relative stability, the tendency to oscillate during its damped response to an input change such as a step function. Gain margin indicates absolute stability and the degree to which the system will oscillate, without limit, given any disturbance.
Enthalpy Enthalpy /ˈɛnθəlpi/ ( listen) is a property of a thermodynamic system. The enthalpy of a system is equal to the system's internal energy plus the product of its pressure and volume.[1][2] For processes at constant pressure, the heat absorbed or released equals the change in enthalpy.