The algorithm of mapping the user’s location near a fork is
shown in Table. 1. With the center around the user’s
location (real_u) in the real-world layer, an arbitrary number
of forks (w) within the range of are searched for, and the
distance between real_u and w is calculated. The w that
shows the shortest distance is determined to be the user’s
location (info_u) in the information layer.