The software application published by MFB Geo Consulting that includes a feature/module/file named "femapnx_nas_topol_fep" is likely related to FEMAP, which is a pre- and post-processing software for finite element analysis (FEA).
The specific feature/module "femapnx_nas_topol_fep" appears to be related to topology optimization in the context of finite element modeling, particularly with respect to using NAS (Nastran) solvers. Topology