Semi-homotopy and semi-fundamental groups
  In this study we introduce the notions of semi-homotopy of semi-continuous maps and of semi-paths. We also construct a group structure, which will be called semi-fundamental group, using semi-loops and explore some properties of semi-homotopy and semi-fundamental groups. 
Ayhan Erciyes, Ali Aytekin, Tun\c{c}ar \c{S}ahan
math.AT math.GN