<math>K_{fs}=\frac{\bar{C_{i}a^{2}}}{PT_{i}\left [ 2\bar{H_{i}^{2}}+\bar{C_{i}}a^{2}+\left ( \frac{2\bar{H_{i}}}{a^*} \right ) \right ]}</math> | <math>K_{fs}=\frac{\bar{C_{i}a^{2}}}{PT_{i}\left [ 2\bar{H_{i}^{2}}+\bar{C_{i}}a^{2}+\left ( \frac{2\bar{H_{i}}}{a^*} \right ) \right ]}</math> |