Abstract: In a file sharing system, a key manager unit realizes a correspondence between the first user identifier and the first public key in response to a registration request of the first user, generates a first key material for encrypting the first file into a first encrypted file, and generates a first credential according to the first user identifier, the first file identifier, the first public key and the first key material after receiving an access-right claim request to the first file from the first user. A file storage unit stores the first encrypted file and the first credential. The first user uses the first user identifier, the first file identifier and the first private key to retrieve the first key material out of the first credential, and uses the first key material to decrypt the first encrypted file into the first file.

Abstract: An optical system affixed to an electronic apparatus is provided, including a first optical module, a second optical module, and a third optical module. The first optical module is configured to adjust the moving direction of a first light from a first moving direction to a second moving direction, wherein the first moving direction is not parallel to the second moving direction. The second optical module is configured to receive the first light moving in the second moving direction. The first light reaches the third optical module via the first optical module and the second optical module in sequence. The third optical module includes a first photoelectric converter configured to transform the first light into a first image signal.

Abstract: In a method for displaying a notification, a display device receives a push notification associated with an application program through a communication network, and a visual media signal from an external computing device. The display device subsequently generates a to-be-displayed message based on the push notification, and a visual media based on the visual media signal. Then, the display device displays at least one of the visual media and the to-be-displayed message on a display screen of the display device. In cases that the display device is connected to the external computing device, the display device displays the visual media and the to-be-displayed message simultaneously on the display screen.

Abstract: A cantilever-type standoff includes a column body, a plurality of cantilevers, a plurality of blocking plates, and a plurality of bumps. The cantilevers are respectively disposed on opposite end surfaces of the column body. The blocking plates are respectively parallel to the cantilevers. A plurality of clamping grooves are respectively defined by the blocking plates and the cantilevers. The bumps are respectively disposed on surfaces of the cantilevers facing the blocking plates.

Abstract: A cantilever-type standoff includes a column body, a plurality of cantilevers, a plurality of blocking plates, and a plurality of bumps. The cantilevers are respectively disposed on opposite end surfaces of the column body. The blocking plates are respectively parallel to the cantilevers. A plurality of clamping grooves are respectively defined by the blocking plates and the cantilevers. The bumps are respectively disposed on surfaces of the cantilevers facing the blocking plates.