Abstract: An apparatus for controlling temperatures of a mold includes a first heating system, a second heating system, and a cooling system. The first heating system is used for pre-heating medium therein. The second heating system is used for further heating the pre-heated medium provided by the first heating system, and providing the heated medium for the mold after draining out preexisting leftover medium in the mold, before injection molding. The cooling system is used for cooling down the mold after injection molding. A relative method for controlling temperatures of the mold is provided as well.

Abstract: A method of using an electronic key for inserting an electronic seal into contents of a document in a computer system, whereby the electronic key is provided with a memory, and the computer system comprises a storage device and an add-in program. The method includes: (a) inserting the electronic key into the computer system, then utilizing the add-in program to define the electronic seal and generate a corresponding random number, and storing the random number into the storage device and the memory; (b) utilizing the add-in program to insert the electronic seal into the contents of the document and generate attributes of the document, thereat inserting the attributes of the document into the contents of the document.

Abstract: The present invention provides a computer joystick with high accuracy and stability. The computer joystick comprises a housing, a control stick, two perpendicular sliding channels, two guiding plates, a sliding plate, and two optical encoders. The two guiding plates are horizontally installed in the two sliding channels. The sliding plate is horizontally installed at a bottom end of the control stick in a slidable manner and comprises a recess and two linear sliding holes. Each of the guiding plates comprises a protruding button installed in a corresponding linear sliding hole of the sliding plate. The two optical encoders are used for detecting displacements of the two guiding plates in the two sliding channels and generating corresponding displacement signals.