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A possible model of twin high-frequency QPOs (HF QPOs) of microquasars isexamined. The disk is assumed to have global magnetic fields and to be deformedwith a two-armed pattern. In this deformed disk, set of a two-armed ($m=2$)vertical p-mode oscillation and an axisymmetric ($m=0$) g-mode oscillation areconsidered. They resonantly interact through the disk deformation when theirfrequencies are the same. This resonant interaction amplifies the set of theabove oscillations in the case where these two oscillations have wave energiesof opposite signs. These oscillations are assumed to be excited mostefficiently in the case where the radial group velocities of these two wavesvanish at the same place. The above set of oscillations is not unique,depending on the node number, $n$, of oscillations in the vertical direction.We consider that the basic two sets of oscillations correspond to the twinQPOs. The frequencies of these oscillations depend on disk parameters such asstrength of magnetic fields. For observational mass ranges of GRS 1915+105, GROJ1655-40, XTE J1550-564, and H1743-322, spins of these sources are estimated.High spins of these sources can be described if the disks have weak poloidalmagnetic fields as well as toroidal magnetic fields of moderate strength. Inthis model the 3 : 2 frequency ratio of high-frequency QPOs is not related totheir excitation, but occurs by chance.

A Resonantly-Excited Disk-Oscillation Model of High-Frequency QPOs of Microquasars