| 摘要 |
PROBLEM TO BE SOLVED: To properly call attention to the owner of a portable terminal without increasing useless traffic by exchanging only required information in response to the change of circumferential brightness. SOLUTION: The portable terminal includes a transmitting part for transmitting an in-prescribed-place existence signal for reporting existence in a prescribed place to an information providing device or a server, a receiving part for receiving a mobile body existence signal for reporting that a mobile body approaches or exists in the prescribed place from the information providing device or the server, a reporting part for reporting that approach or existence of the mobile body to/in the prescribed place through the use of the mobile body existence signal received by the receiving part, a light detecting part for detecting brightness, and a transmission determining part for determining whether the transmitting part transmits the in-prescribed-place existence signal or not through the use of the brightness detected by the light detecting part. COPYRIGHT: (C)2005,JPO&NCIPI |
