(a)
(b)
(c)
(d)
(e)
(f)
Figure 3: The major principal stress-time and AE energy-time curves of coal samples. (a) Sample M (rate: 2.77 mm/min). (b) Sample N (rate: 6.12 mm/min). (c) Sample O (rate: 4.26 mm/min); (d) Sample P (data loss). (e) Sample Q (rate: 3.86 mm/min); (f) Sample R (rate: 4.78 mm/min).