All existing methods of embedded damage-detecting sensors require an external power source and a means of transmitting the data to a central processor. This paper presents a novel selfpowered strain sensor capable of transmitting data wirelessly to a remote receiver. This paper illustrates the performance of the sensor through the theoretical and experimental analysis of a simple damaged beam. The results show that a sensor powered through the conversion of mechanical to electrical energy is viable for detecting damage. The potential bene®ts of this sensor include ease of implementation during manufacture of the structure, and the use of an environmentally safe and renewable power source.

Interest of the hand effect on the electromagnetic wave are internationally increasing with the increase of the use of the mobile phone. IEC TC106(International Electrotechnical Commission, Technical Committee 106) promotes international research exchange program in order to reflect the effect of human hands in the standard assessment method of human exposure dosimetry by the electromagnetic wave of mobile phones. Since current commercialized hand phantom is manufactured by taking into account the average size of westerners and provides only one grip posture, it imposes many restrictions on the accurate SAR measurement. Therefore, the development of proper hand phantom accounting for domestic situation and various grip posture capability is essential in order to analyze the accurate effect of human hand on the exposure estimation. In this paper, a jelly hand phantom suitable for Korean was manufactured with various grip posture capability at 835 MHz and 1,800 MHz bands. Although the tolerances of permittivity and conductivity of the manufactured hand phantom are with ±10 % each, it was much less than CTIA(Cellular Teleco-ⓒ