Disclosed is a high-efficiency phase shift modulation method suitable for use in a traditional DCAC single-phase full-bridge inverter. It is characterized in that a gas rectification member for rectifying and guiding a gas generated from an inflator up to the vicinity of a part of the airbag, inflating in the initial expansion thereof, is provided substantially at the central part of the airbag. The tubular sides are attached by a portion of the device that can cover either the top portion of the joint or the underside of the joint. The bottom surface of each indentation runs substantially parallel to the axis of the drive shaft. According to the page dynamic allocation and mapping technology, by variable memory allocation, fragmentation may be prevented and page faults may be minimized in response to pages being loaded through page mapping of the non-volatile memory. After determining a plan date, the processor determines an available date for each supply in the supply structure.