TY JOUR TI NETWORK MODELING OF THE PROCESS OF ANAEROBIC DIGESTION OF MANURE KW modified Petri nets KW technological process of anaerobic digestion of manure KW simulated systems KW chemical-technological system KW computer modeling JO Agrobiotechnologies and digital farming AU Savdur, S.N. PY 2023 IS 2 PB Kazan state agrarian University