This circuit is a distributed adjustable-output voltage regulators using LM317 three-terminal adjustable-output voltage regulator ICs. Each of the LM317 ICs provides adjustable regulated voltage to localized areas in a circuit board. There is a single resistor that sets the programming current. Adjustment of the output voltage is done using a common variable resistor.
aryniec-pw says:
But do you happen to have the MultiSim source of LM317 component, but built as a functional block diagram (i.e. https://i.ibb.co/SvkYTny/lm317.png) and not just simple visual representation (i.e. https://i.ibb.co/93qCQdy/image.png)?