Abstract: A power assist device may include a motor, a motor driving circuit, sensors to output signals in accordance with a rotational speed of the wheel, a memory, and a signal processor. The memory stores information of a parameter defining a transfer function that interrelates a total torque to be input to the vehicle and a rotational speed of the wheel, and an inverse transfer function thereof. Based on the inverse transfer function, the signal processor determines an estimated value of total torque from a detected value of rotational speed of the wheel. Moreover, based on the transfer function, the signal processor updates at least a portion of the information of the parameter so that, for example, an error between a detected value of rotational speed of the wheel and an estimated value of rotational speed of the wheel as determined from the estimated value of total torque is reduced.

Abstract: A power assist device may include a motor, a motor driving circuit, sensors to output signals in accordance with a rotational speed of the wheel, a memory, and a signal processor. The memory stores information of a parameter defining a transfer function that interrelates a total torque to be input to the vehicle and a rotational speed of the wheel, and an inverse transfer function thereof. Based on the inverse transfer function, the signal processor determines an estimated value of total torque from a detected value of rotational speed of the wheel. Moreover, based on the transfer function, the signal processor updates at least a portion of the information of the parameter so that, for example, an error between a detected value of rotational speed of the wheel and an estimated value of rotational speed of the wheel as determined from the estimated value of total torque is reduced.

Abstract: A thermoelectric material includes a semiconductor substrate, a semiconductor oxide film formed on the substrate, and a thermoelectric layer provided on the oxide film. The semiconductor oxide film has a first nano-opening formed therein. The thermoelectric layer has such a configuration that semiconductor nanodots are piled up on or above the first nano-opening so as to form a particle packed structure. At least some of the nanodots each have a second nano-opening formed in its surface, and are connected to each other through the second nano-opening with their crystal orientation aligned. The thermoelectric material is produced through steps of oxidizing the substrate to form the semiconductor oxide film thereon, forming the first nano-opening in the oxide film, and epitaxially growing to pile up the plurality of nanodots on the first nano-opening. As a result, it is possible to provide the thermoelectric material superior in thermoelectric conversion performance.

Abstract: A thermoelectric material includes a semiconductor substrate, a semiconductor oxide film formed on the substrate, and a thermoelectric layer provided on the oxide film. The semiconductor oxide film has a first nano-opening formed therein. The thermoelectric layer has such a configuration that semiconductor nanodots are piled up on or above the first nano-opening so as to form a particle packed structure. At least some of the nanodots each have a second nano-opening formed in its surface, and are connected to each other through the second nano-opening with their crystal orientation aligned. The thermoelectric material is produced through steps of oxidizing the substrate to form the semiconductor oxide film thereon, forming the first nano-opening in the oxide film, and epitaxially growing to pile up the plurality of nanodots on the first nano-opening. As a result, it is possible to provide the thermoelectric material superior in thermoelectric conversion performance.