Time evolution of the radial distribution of v_z (top panels) and σ_z (bottom panels) in the stellar disks over 4 Gyr. Left, middle, and right: r1c14, r1c14ldm, and r1c14ldmsf06 models, respectively. For the vertical velocity v_z, the color distribution inside the color bar is fixed across all three models to ensure direct comparison, although the overall range of the color bar is not fixed. Sudden fluctuations in the v_z maps indicate the onset of buckling instability. For the vertical velocity dispersion σ_z, the color scale is fixed for values in the range 30-80 km s⁻¹. The black regions indicate strong vertical heating of the stellar disk.