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SWALLOW-TYPE SUPPORTING SYSTEM CONSIST OF MIDDLE-DISTANCE-CANTILEVER BEAM-DISTANCE MEMBERS AND ROCK ANCHORS AND ROTARY BUILDING-IN TECHNOLOGY FOR SECURING MINE DRIFTS AND SIMILARS AGAINST CAVING
SWALLOW-TYPE SUPPORTING SYSTEM CONSIST OF MIDDLE-DISTANCE-CANTILEVER BEAM-DISTANCE MEMBERS AND ROCK ANCHORS AND ROTARY BUILDING-IN TECHNOLOGY FOR SECURING MINE DRIFTS AND SIMILARS AGAINST CAVING