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 for recognizing the step movement sequence of a control rod drive mechanism of a nuclear reactor, which withdraws and inserts a control rod of a nuclear reactor, includes the steps of: measuring current and voltage flowing through an electromagnetic coil used in the control rod drive mechanism of the nuclear reactor; calculating inductance of the coil by using the measured current and voltage; calculating a distance between a rotor and a stator of the control rod drive mechanism on the basis of the calculated inductance; and recognizing the step movement sequence of the control rod drive mechanism on the basis of the calculated distance. This method ensures good reliability in determining the step movement sequence, allows easy implementation using a digital signal processor, and is hardly affected by external factors such as noise.

Abstract: A method for recognizing the step movement sequence of a control rod drive mechanism of a nuclear reactor, which withdraws and inserts a control rod of a nuclear reactor, includes the steps of: measuring current and voltage flowing through an electromagnetic coil used in the control rod drive mechanism of the nuclear reactor; calculating inductance of the coil by using the measured current and voltage; calculating a distance between a rotor and a stator of the control rod drive mechanism on the basis of the calculated inductance; and recognizing the step movement sequence of the control rod drive mechanism on the basis of the calculated distance. This method ensures good reliability in determining the step movement sequence, allows easy implementation using a digital signal processor, and is hardly affected by external factors such as noise.