Abstract: A fluid level measurement system using a buoyant body includes a guide part installed in a direction perpendicular to the bottom surface of a fluid storage tank, and provided with a space in which a fluid can move therein; a buoyant body inserted into the guide part, and configured to float along the surface of the fluid inside the guide part; and a measurement part coupled to the top end of the guide part, and configured to measure the level of the surface of the fluid inside the fluid storage tank by transmitting a signal toward the buoyant body in the inner space of the guide part and then receiving a signal reflected from the buoyant body.

Abstract: A method and system for monitoring energy consumption is provided. The method for monitoring energy consumption estimates a number of people in a room based on an indoor CO2 concentration, and determines whether an amount of energy consumed indoors is proper or not based on the estimated number of people in the room. Accordingly, a waste of energy can be prevented by monitoring when a proper amount of energy is consumed in comparison with the number of people in a room. In addition, the number of people in the room can be easily estimated at low cost prior to determining whether energy consumption is proper or not.

Abstract: Provided are an apparatus and method for asset tracking based on a ubiquitous sensor network (USN) using a motion sensing. The apparatus may include: a motion sensing manager to receive motion sensing information from a sensor; a filtering processor to filter the motion sensing information based on a filtering parameter and to determine whether a motion occurs based on the filtered motion sensing information; and a location information update (LU) manager to perform LU depending on whether the motion occurs.

Abstract: Provided are an apparatus and method for asset tracking based on a ubiquitous sensor network (USN) using a motion sensing. The apparatus may include: a motion sensing manager to receive motion sensing information from a sensor; a filtering processor to filter the motion sensing information based on a filtering parameter and to determine whether a motion occurs based on the filtered motion sensing information; and a location information update (LU) manager to perform LU depending on whether the motion occurs.