There are multiple definitions:

1. recirculated systemic flow(English)

   • RPF, SF
   • Hemodynamics

2. ROI-spread-function(English)

   • ROI
   • Medical imaging

3. random survival forest(English)

   • PTFR, CPHR, HF, ML
   • Statistics, Machine learning
   • https://doi.org…872-025-05165-x