TY JOUR TI Theoretical grounds for determining optimal trim of river-sea vessels KW optimal trim of the vessel KW theoretical foundations KW use of optimal trim to improve seaworthiness KW medium resistance against ship propulsion KW wave height JO Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies AU Ershov, A.. AU Mishenko, V.. PY 2021 IS PB Astrakhan State Technical University