I. Introduction (Heading 1)
There are many kinds of processes, which are multi-mode (multi-regime) in nature. Typical examples are the photovoltaic (PV) systems that can operate under different conditions in the different seasons of the year. The following Fig. 1 gives a graphical illustration for two operating modes (in winter and in summer) of a PV system.
Illustration of different operating conditions for a photovoltaic system in winter and summer days