Abstract: Embodiments of the present disclosure provide a method, device and computer program product for managing backup data. The method comprising: obtaining historical information of a plurality of historical operations on target data in a backup storage device during a first time period, the historical information indicating at least types and time of occurrences of the plurality of historical operations; determining, based on the historical information, whether the target data is to be rewritten to the backup storage device within a second time period after the first time period; and in response to determining that the target data is to be written to the backup storage device within the second time period, adjusting an expiration time of the target data in the backup storage device. Based on such a manner, efficiency of the backup system can be increased.

Abstract: A forced separation device includes a transmission shaft, a main shaft, an electromagnetic transmission mechanism, a blasting separation mechanism and a pressure-resistant cabin. A pressing cover is fastened to the upper portion of the pressure-resistant cabin. The electromagnetic transmission mechanism is provided with a driving chuck and a driven chuck. The driving chuck is connected with the transmission shaft, the driven chuck is connected with the main shaft, the pressing cover is welded with the transmission shaft, and the driven chuck is welded with the lower portion of the pressure-resistant cabin. The blasting separation mechanism is provided with explosive packages and detonators. A plurality of explosive packages are distributed between the pressing cover and the top surface of the pressure-resistant cabin, and each explosive package is connected with the corresponding detonator respectively. The pressure-resistant cabin is further internally provided with a storage battery.

Abstract: A forced separation device for a submarine drilling machine and a drilling tool comprises a transmission shaft, a main shaft, an electromagnetic transmission mechanism, a blasting separation mechanism and a pressure-resistant cabin, a gland is fastened to the upper portion of the pressure-resistant cabin, the electromagnetic transmission mechanism is provided with a driving sucker and a driven sucker, the driving sucker is connected with the transmission shaft, the driven sucker is connected with the main shaft, the gland is welded with the transmission shaft, and the driven sucker is welded with the lower portion of the pressure-resistant cabin; the blasting separation mechanism is provided with explosive packages and detonators, a plurality of explosive packages are distributed between the gland and the top surface of the pressure-resistant cabin, and each explosive package is connected with the corresponding detonator respectively; and the pressure-resistant cabin is further internally provided with a stor