Abstract: Embodiments of the present disclosure relate to a method, an apparatus, an electronic device, and a medium for data transfer. The method includes generating, based on metadata of to-be-transferred data and a blockchain including a data transfer record, an ownership certificate of an initiator of a transfer for the to-be-transferred data. The method further includes generating a new transfer record for validation by a blockchain system, where the new transfer record includes the ownership certificate and validation information associated with a receiver of the transfer. The method further includes transferring the to-be-transferred data to the receiver in response to that the new transfer record passes validation of the blockchain system. In this way, the data transfer record may be reliably stored in the blockchain, thereby providing reliable integrity protection and data traceability for a storage system.

Abstract: An ultrasonic motor-based regulated variable-damping vibration isolator, includes a base, a magnetorheological damper, and an adapter plate. The magnetorheological damper is mainly used to support and deplete the energy of vibration; the magnetorheological damper includes an upper cavity, a lower cavity, a connecting ring, a permanent magnet, orifices, a magnetic permeable ring, an ultrasonic motor and the like; a magnetorheological fluid is stored in the upper and lower cavities defined by bellows. The magnetorheological damper uses the ultrasonic motor to drive the permanent magnet to rotate to adjust the overlap ratio of the permanent magnet and the orifices, that is, to adjust the number of the orifices entering the magnetic field of the permanent magnet, so as to change the damping intensity of the damper. After rotating in place, the ultrasonic motor can be powered off and self-locked.

Abstract: Embodiments of the present disclosure provide a method for file backup, an electronic device and a computer program product. The method comprises: dividing a set of files to be backed up into a plurality of subsets of files, files in each of the plurality of subsets of files being of a same file type. The method also comprises: generating a plurality of backup files based on the plurality of subsets of files respectively, the plurality of backup files corresponding to a plurality of file types of files in the plurality of subsets of files respectively. The method further comprises: generating an overall backup file corresponding to the set of files based on the plurality of backup files.

Abstract: Embodiments of the present disclosure provide a method for file backup, an electronic device and a computer program product. The method comprises: dividing a set of files to be backed up into a plurality of subsets of files, files in each of the plurality of subsets of files being of a same file type. The method also comprises: generating a plurality of backup files based on the plurality of subsets of files respectively, the plurality of backup files corresponding to a plurality of file types of files in the plurality of subsets of files respectively. The method further comprises: generating an overall backup file corresponding to the set of files based on the plurality of backup files.