We demonstrate that the four high-frequency QPOs observed in GRS 1915+105 can
be interpreted as the oscillation modes on disks which non-linearly and
resonantly interact with a warp. The warp is assumed to be a low-frequency
global pattern on the disk. This identification suggests that the relevant
mass, M, and spin, a, of GRS 1915+105 are, M=13∼14M⊙​ and
a=0∼0.15Comment: 4 pages, 5 figures, accepted in PASJ Vol.56(2004) No.5, The English
was improved on September