The invention features a computer-implemented method for playing back an announcement message to a user device. The glass substrate layers can have similar CTE. However, other materials may be used for the resonator. The rib being divided along the front parting plane and the edge portions of the divided rib portions opposing the outer periphery of the main frame portion are integrally joined. The honeycomb structure is made of cordierite excellent in thermal shock resistance even with large pore diameters and high porosity.