Abstract: A testing method includes at least one client computer executing a system test; when a system error occurs at the at least one client computer, the at least one client computer reporting a test result of the system test to a server in real time; the server generating a notification instruction to notify a system administration group; a system administrator in the system administration group acquiring a permission and remotely logging in to the server; and the system administrator logging out of the server and releasing the permission.

Abstract: A seat includes a back-up unit which includes a shaft fixed to the rear side of a backrest and the two ends of the shaft are pivotably connected to two armrests of the seat. A resilient member is mounted to the shaft and a restriction unit is connected to the shaft. The backrest tilts backward when a user sits in the seat and pivots forward to its upright position by the resilient member and the restriction unit when the user leaves from the seat.

Abstract: An expansion screw includes an expansion sleeve, and an expanding block; the sleeve has elongated gaps extending lengthwise from a tail end, and engaging portions on an inner side; the expanding block has a screw hole, and is in the shape of a truncated cone formed with outer engaging portions for fitting the inner engaging portions of the sleeve; a screw is passed through the sleeve, and screwed into the smaller end of the expanding block with the block smaller end being passed into the sleeve tail end; thus, when the screw is further turned, the block will be made to pass into the sleeve to expand the sleeve; the outer engaging portions engage respective ones of the inner engaging portions such as to prevent angular displacement of the expanding block relative to the expansion sleeve, and helping the expanding block move into the expansion sleeve.