A semiconductor memory device which more reliably retains electrons trapped in its charge-trapping regions. A first gas-permeable inner tube is disposed coaxially to the long axis of the casing and fixedly joined at the gas inlet end to the casing cover, while a second gas-permeable outer tube which is also disposed coaxially with the long axis of the casing and has a radius rA greater than the radius rI of the inner tube but smaller than the radius rG of the casing. There is provided a honeycomb filter in which a crack is not generated by thermal stress during use, especially at a regeneration time and which is superior in durability. To ensure operation, the primary control unit receives state information from the router resources and maintains the state information for consumers, i. An actuator in the form of an RF receiver is electrically coupled to the inlet valve and the pump and a remote transmitter is operatively coupled to the receiver.