Communication terminal, position management system, and communication method

A position management system comprising:

• a communication terminal;
• and
• a position information management system, wherein
• the communication terminal includes
• a receiving unit configured to receive position information that has been transmitted from a transmission device for transmitting predetermined position information,
• a detecting unit configured to detect a change in an acceleration of the communication terminal,
• a movement detecting unit configured to detect a movement of the communication terminal based on the position information and information expressing the change in the acceleration, and
• a sending unit configured to send the position information to the transmission device, when the movement is detected, wherein
• the position information management system is configured to communicate with the communication terminal via a gateway, and to manage the position information sent from the sending unit of the communication terminal.

A communication method executed by a communication terminal, the communication method comprising:

• receiving position information that has been transmitted from a transmission device for transmitting predetermined position information;
• detecting a change in an acceleration applied to the communication terminal;
• detecting a movement of the communication terminal based on the position information and information expressing the change in the acceleration;
• and
• sending the position information to the transmission device, when the movement is detected.