Abstract: Provided is a power saving control method and system for data storage devices or electrical equipment. Herein, data items are divided into groups according to required response times or access frequencies. The groups of data items are allocated to data storage devices or pieces of electrical equipment. A data storage device or electrical equipment to which data that may be accessed using a long response time at a low access frequency is set to a power-saving mode of a higher level. Consequently, the data storage devices or pieces of electrical equipment are provided with power-saving features of different levels. Eventually, energy saving can be achieved more efficiently.

Abstract: Provided is a power saving control method and system for data storage devices or electrical equipment. Herein, data items are divided into groups according to required response times or access frequencies. The groups of data items are allocated to data storage devices or pieces of electrical equipment. A data storage device or electrical equipment to which data that may be accessed using a long response time at a low access frequency is set to a power-saving mode of a higher level. Consequently, the data storage devices or pieces of electrical equipment are provided with power-saving features of different levels. Eventually, energy saving can be achieved more efficiently.

Abstract: An ultrasonic printing method by which recording of a high resolution can be achieved. In the ultrasonic printing method, some or all of a plurality of ultrasonic oscillators are selectively driven in such phases that a difference in phase at a predetermined point between a reference ultrasonic wave from one of the selected ultrasonic oscillators and another ultrasonic wave from any other one of the selected ultrasonic oscillators is equal to or less than one-fourth a wavelength of the ultrasonic waves in a transmission medium for the ultrasonic waves from the selected ultrasonic waves to the predetermined point. The ultrasonic printing method can be applied to various printing apparatus for which recording of a high resolution is required.

Abstract: There is provided an ultrasonic printer in which convergent ultrasounds are radiated to emit an ink near a convergent point of the convergent ultrasounds in the form of an ink droplet and deposit the ink droplet on a recording medium such as a paper sheet, thereby performing a recording on the recording medium with multiple ink dots, with higher resolution. The ultrasonic printer has a plurality of ultrasonic transducers which transmit phase-controlled ultrasonic waves to form an convergent ultrasonic acoustic beam.

Abstract: A system including a plurality of processing units wherein one power source is connected to the plurality of processing units, is constituted such that when a total of maximum rated currents of the processing units exceeds an allowable current of the power source, an allowance or nonallowance of the power supplied to the processing units is determined from a state of the power source and the power supply is controlled thereby, and whereby the power source does not become overloaded. Thus, the system avoids overloading the power source if a sum of the maximum rated currents of respective connected processing units exceeds the allowable current of a power source.