| 1 | The stability criterion is pointed out in this paper. | |
| 2 | One can show that the discriminant of the numerator is positive. | |
| 3 | The discriminant of the stability of the air flow at mining areas was educed in this paper, and idiographic prevent measures were put forward. | |
| 4 | A discriminant analysis was performed to analyze each parameter and to compute a functional score. | |
| 5 | In this article, the formula on winding density and discriminant for ribboning are deduced. |