“…In the currentramp-up phase of the tokamak operation they were used to explain the anomalously strong current penetration [5,6,7] and short-wavelength MHD activity (e.g., Mirnov oscillations) [6,8]. Experimental observations of partial and compound sawtooth crashes (internal disruptions) [9,10,11,12,13] may be explained through kink-tearing modes on double/multiple resonant surfaces [14,15,16,17]. Phenomena associated with low-beta disruptions in the presence of double resonant surfaces with q s > 1 may also be understood in terms of DTM activity [14,18,19].…”