PERSPEKTIVY PRIMENENIYA AKUSTICHESKIKH METODOV PRI PROGNOZE I PREDOTVRASHCHENII GAZODINAMICHESKIKH YAVLENIY I KRUPNOPLOSHCHADNYKH OBRUSHENIY KROVLI V UGOL'NYKH SHAKHTAKH [PROSPECTS OF APPLICATION OF ACOUSTIC METHODS FOR THE PREDICTION AND PREVENTION OF GAS DYNAMIC PHENOMENA AND LARGE-ARISING ROOF CRANES IN COAL MININGS]