TY JOUR TI CALCULATION OF CONCENTRATION OF HARMFUL SUBSTANCES INSIDE THE ROOMS DEPENDING ON CONCENTRATION OF HARMFUL SUBSTANCES FLOWING FROM OUTSIDE KW air humidity KW concentration of CO2 KW continuous model KW differential equations JO Vestnik of Astrakhan State Technical University AU Bednářová, P.. AU Chládek, P.. AU Šubrt, R.. PY 2013 IS 2013 PB Astrakhan State Technical University