“…Nonetheless, it still suffers from slow convergence rates [2,11,12] and unexpected breakdown in a practical engineering problem of the BEM [13] because the coefficient matrix of the BEM is too ill-conditioned. Additionally, the restarted version of GMRES algorithm, which has been considered as the standard remedy to the unexpected breakdown and the large memory requirements, can still make the convergence rates worse [14] and fail to converge by the complete stagnation [15].…”