improve docu

Author: ufechner7

docs/src/explanation.md

@@ -4,6 +4,8 @@ Flowchart that describes how this software works:
 
 ![Flowchart](Flowchart.png)
 
+**AIC:** Aerodynamic Influence Coefficient (AIC). The AIC matrix represents the relationship between the induced velocities or pressures on aerodynamic surfaces and the circulation strength or modal deformations of the lifting surfaces.
+
 ### References:
 
 [Fast Aero-Structural Model of a Leading-Edge Inflatable Kite](https://www.mdpi.com/1996-1073/16/7/3061) by Oriol Canon, Mac Gaunaa and Roland Schmehl, Energies 2023 16(7),   doi: 10.3390/en16073061