This demonstration shows the actual application of our wireless AMI[1] system, AMR Xpider. This system consists of a sink node and multiple relay nodes. Hundreds of sensing nodes, which are connected to the relay node, transfer metering data to the MDMS (meter data management system). A total of 20,000 AMR Xpider units have been installed in apartments in South Korea for gas metering during the past three years. The AMR Xpider units are used for actual billing purposes. They operate with battery life of at least five years (generally, around seven years), with an average communication success rate of 98%.

Ubiquitous is a Latin-derived word meaning "to exist at any time and place" likes water or air. In computing, the word "ubiquitous" indicates an environment in which users have access to networks without any limitation regarding computers, networks or places. Important issues in building Ubiquitous Korea (U-Korea) are the social problems appearing with a rapid increase in the old age population. Nowadays, with the rise of the nuclear family, the increase in the number of elderly people living alone, and the change in the status of women, both wives and husbands are employed outside the home, and the relatives who would be responsible for supporting the elderly sometimes are on long or short business trips, and it happens that old people can't be looked after. Therefore the government developed a wireless paging system for the sick , disabled, old and weak so that when an emergency happens, by just simply dialing 119, an emergency aid center could take prompt action. However, the present wireless paging systems composing the under-layer of the emergency aid information system have some problems, such as, a lack of reliability, problems among terminals, mobile transmitters and receiving terminals, the users' refusal to admit the need for the system and poor operational skills, administrators' perfunctory management and checks, etc. On account of these problems, the system efficiency has degraded and therefore a system upgrade is necessary. In this paper, we attempt to evaluate the newly implemented SAFE119 system, a new wireless paging system seeking to correct the problems of the current system.