Abstract: A method and device for milling a large-diameter aspheric surface by using a splicing method and a polishing method to solve the problems of large time consumption and serious tool wear in the machining of a meter-scale large-diameter aspheric surface are disclosed. where an aspheric surface is discretized into a series of rings with different radii, and the rings are sequentially machined via generating cutting by using an annular grinding wheel tool with an outer diameter less than ¼ of a diameter of the aspheric surface; the rings are equally spaced, there are a total of N rings, and a width of any ring is jointly determined by the Nth ring, the (N?1)th ring, positioning accuracy and a generatrix equation of the aspheric surface; and the aspheric surface is enveloped by a large number of rings. A contact area between the tool and a workpiece surface is rings.

Abstract: When it is recognized by the CPU that the user uses the system, and the provability of the HDD-access is high. Based on this judges, the HDD timer register is reset, in order to not automatically stop the disk driving motor. The user has stopped the input manipulation, before the HDD-timer register is counted down by the timer, when the value of the HDD-timer register becomes "0". At this time, the directive data of motor-off is set to the motor-off register (DMOFF) within the HDD due to the procession caused by the timer-interruption. In accordance with the directive data, the disk-driving motor is controlled so as to be automatically stopped.

Abstract: System and method for a computer system having a hard disk drive (HDD) having a function of stopping the disk driving motor of the HDD after an elapse of a predetermine period of time after accessing the HDD. A use/non-use state of the computer system is monitored while the system is being powered. Different shut off times are set based on whether a use or non-use state is detected. After the set periods of time, computer shut down occurs.

Abstract: A resource allocation request and a resource release request of a PC card modem sent to a communication driver via a modem driver are hooked by a power saving driver. When the power saving driver detects that the resource allocation request is issued, the power saving driver first begins to supply power to the PC card modem by using a card service. Thereafter, the power saving driver transmits the hooked resource allocation request to the communication driver. Further, when the power saving driver detects that the resource release request is issued, the power saving driver transmits the hooked resource allocation request to the communication driver and stops the supply of power to the PC card modem by using the card service.