According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array and a control circuit. The convertible wall has a restoring mechanism to move it back to its original barrier position upon removal of the weight of the mother’s arms. During the injection process the nozzle needle is outside the melt flow and cannot cause said melt flow to swirl and is not radially loaded by the melt flow. By sliding the sliding bar forward or rearward, the rod of the rotating arm slides along the driving portion of the guiding slot to rotate the rotating arm forward to stretch the cable or rotate the rotating arm rearward to wind up the cable. The communication session is then transferred to the second device by launching a new communication session on the second device and transferring the context of the communication session corresponding to the first device to the new communication session on the second device. The method including: providing the munition with a power supply having a piezoelectric material for generating power from a vibration induced by the munition; monitoring an output from the power supply; and determining whether the output of power from the power supply has dropped below a predetermined threshold.