Methods and apparatus for establishing communication between a Mobile Node and a Home Agent are disclosed. These process includes the bioconversion of at least two amino compounds and at least one reducing sugar in the presence of a yeast. In the R-T-B system rare earth sintered magnet of the present invention, the area ratio of the partial surface of the above described sintered body covered with the above described carbon compound layer to the entire surface thereof is preferably between 10% and 90%. By wearing a self-contained transmitting sensor 10-9 on a user 40 physical quantities such as temperature, humidity and illumination at a place in which the user is located can be controlled to desired values wherever the user moves. When an amount of power transferred is sufficient for the distance, the transfer of power is terminated.