TY JOUR TI THE IMPACT OF CATASTROPHIC FAILURES ON THE EFFECTIVENESS OF QS WITH UNEQUAL CHANNELS KW QUEUING SYSTEM KW DEVICES OF DIFFERENT PERFORMANCE KW CATASTROPHIC FAILURES KW PROBABILITY OF FAILURE KW HETEROGENEITY OF PERFORMANCE JO Herald of Technological University AU Galiullin, R.F. AU Il'ina, A.A. PY 2026 IS 29 PB Kazan National Research Technological University