For the construction of the wall, we set the default value of ϵ = 1.0. The projection of samples to the latent space is always normalized to the interval [-1, 1], and setting ϵ = 1.0 shifts the harmonic wall by half of this range. This adjustment expands the relevant sampling region within the latent space, effectively increasing the speed and scope of PES exploration as more data accumulate in the global dataset under the multitask scheme.