The terms “Pink Puffers” and “Blue Bloaters” have been around for many years. They are used in a colloquial sense by speleologists to describe how cavers react to an elevated concentration of carbon dioxide (CO2) and reduced oxygen (O2) in a cave’s “foul air” atmosphere. Foul air is only found in a small number of Australian caves and is defined as having a noticeable abnormal physiological eff...

To study on the characteristics of the vibration signals of coal and stone hitting the armor plate during caving, a hybrid algorithm based on first order forward difference and wavelet transform modulusmaxima method is presented which can be used in the longwall top coal face. First, in order to reduce the noise interference, the pre-processing of the vibration signals is done by the first orde...

An extraction method for deep-seated thick seam deposits by underground mining with high resource recovery has remained a great challenge Indian engineers, whereas the longwall top coal caving (LTCC) evolved as an effective various geo conditions in China and other counties. The percentage of (TCR) plays predominant role determining feasibility LTCC, which relies on First Top Coal Caving Distan...