A memory device as described herein includes a memory member contacting first and second interface structures. The planetary gear has a sun gear, a carrier rotatably supporting a plurality of pinions each of which engages with the sun gear, a ring gear engaging with the pinions. Each generator also provides control information at each of a plurality of successive time windows T for each bit rate representation. A management ability setting unit changes the manager evaluation value to reduce the management ability of the manager character as the evaluation difference value increases.