Abstract: Disclosed is a whitening composition for external skin application. Containing one or more of Oldenlandia diffusa Willd extract, Rheum undulatum extract and Broussonetia kazinoki extract as an effective ingredient, the whitening composition for external skin application exhibits superior melanogenesis inhibition and skin whitening effect. Accordingly, it may be used in various skin whitening cosmetics.

Abstract: Disclosed is a whitening composition for external skin application. Containing one or more of Oldenlandia diffusa Willd extract, Rheum undulatum extract and Broussonetia kazinoki extract as an effective ingredient, the whitening composition for external skin application exhibits superior melanogenesis inhibition and skin whitening effect. Accordingly, it may be used in various skin whitening cosmetics.

Abstract: A method of checking a parallel port of a personal computer using loopback includes the steps of loopback-connecting pins corresponding to control signals and data signals transmitted to a printer to pins corresponding to status signals transmitted to the computer, checking whether there is a parallel port, stopping the checking when there is no parallel port, generating the control signals and reading looped-back status signals after a predetermined time to check control pins, and generating the data signals and reading looped-back status signals after a predetermined time to check data pins. Accordingly, a parallel port of a personal computer is tested without being connected to a printer, thereby simplifying the a production process. Also, manual printing is not required, thereby reducing test time and production time.

Abstract: A method for upgrading a BIOS using serial communication is provided. In the method, it is possible to collectively upgrade the BIOS's of a plurality of computers using serial communication without using a floppy disk. The method includes the steps of: at a host computer, transferring predetermined BIOS upgrade software and BIOS image data corresponding to a computer to the computer through a selector using serial communication when the computer connected to the host computer through the selector requests the BIOS to be upgraded; and, at the computer which requested the BIOS to be upgraded, upgrading the BIOS by removing the existing BIOS stored in a BIOS ROM and writing the BIOS image data into the BIOS ROM by executing the received BIOS upgrade software. According to the present invention, it is possible to save time in upgrading the BIOS and to collectively upgrade the BIOS's of a plurality of computers.