Abstract: Provided is a method of manufacturing a light-emitting element, the method including positioning a substrate, forming a first separation layer, which includes a first sacrificial layer, an etching control layer on the first sacrificial layer, and a second sacrificial layer on the etching control layer, on the substrate, forming at least one first light-emitting element on the first separation layer, and separating the first light-emitting element from the substrate.

Abstract: A smart metering system using a white space band includes a band search sensor installed in a predefined area which scans a digital public broadcast channel band; a band management server which manages area specific broadcast channel status information based on a scanning result obtained by the band search sensor and which searches a white space band that is an idle channel band of a corresponding area based on the broadcast channel status information to allocate the white space band as a smart metering data transmission channel; and a base station which allocates the smart metering data transmission channel from the band management server and which forms a wireless communication channel between a smart meter and a grid central server via the allocated smart metering data transmission channel.