Abstract: A road surface adaptive adjustable driving wheel is provided, which has the same moving speed as a general circular type wheel while adapting to a road surface state in the same manner as the caterpillar type wheel, and automatically spreads wing portions of the wheel when the wheel reaches a rugged place without the necessity of separate wheel adjustment constituent elements such as a road surface detection sensor and a control unit. The road surface adaptive adjustable driving wheel includes a driving shaft that is rotatable by driving of a motor, auxiliary driving shafts rotatably engaged with the driving shaft, and adjustable driving bodies each having a head portion that is directly engaged with the auxiliary driving shaft and a wing portion extending from the head portion.

Abstract: The present invention relates to an Internet communication method, which can implement smooth bi-directional communication on the Internet between a user of a virtual IP address and a user of a real IP address. The present invention involves forming a client address information table by means of mapping, as a pair, an Internet protocol address (server-recognized IP address) obtained through a network socket and Internet protocol addresses (client-notified IP address) notified of directly by respective clients. Upon receiving a signal asking for an Internet protocol address of a corresponding client to be connected from a client terminal, the server-recognized IP address and the client-notified IP address of the corresponding client are read from said client address information table, which are then provided to the client terminal.