Prediction and Analysis of Abnormal Gas Emission Law in Low-Gas Tunnel Based on K-Line Diagram

Table 1

Graphics of the K-line diagram and their meanings.

Graph
Name	Short red line	A red entity with long lower shadow	A red entity with upper and lower shadows	A red entity with lower shadow	A red entity with an upper shadow
Meaning	Indicating that the growth trend in the cycle is not obvious, which needs further observation	Indicating that the gas concentration increases in the cycle	Indicating that it will jump, open high, and go low in the next period of the cycle	Indicating that the gas concentration may increase in the cycle	Indicating that the gas concentration in the cycle has a strong growth momentum
Graph
Name	A red entity without a shadow	Inverted T-line	T-line	Cross
Meaning	Indicating a strong growth in the next period of the cycle	Indicating that the cycle may be shortened	Indicating that the cycle may expand	Indicating a peak signal or a bottom signal, which indicates that, in the cycle, the trend of the gas concentration interval will change or it will enter a plateau