  The quantum S=1 spin model on the spatially anisotropic triangular lattice is
investigated numerically. The nematic and valence-bond-solid (VBS) phases are
realized by adjusting the spatial anisotropy and the biquadratic interaction.
The phase transition between the nematic and VBS phases is expected to be a
continuous one with unconventional critical indices (deconfined criticality).
The geometrical character (spatial anisotropy) is taken into account by
imposing the screw-boundary condition (Novotny's method). Diagonalizing the
finite-size cluster with N \le 20 spins, we observe a clear indication of
continuous phase transition. The correlation-length critical exponent is
estimated as \nu=0.92(10).
