Abstract: Disclosed are a frictional resistance reducing device that effectively reduces the frictional resistance of a ship, and a ship including same. The frictional resistance reducing device comprises: a first air discharge part formed on the leading undersurface of a ship and discharging air into water; a second air discharge part formed behind the first air discharge part and discharging air into water; and an air supplying source supplying air to the first air discharge part and the second air discharge part, wherein the first air discharge part and the second air discharge part are disposed in-line along the lengthwise direction of the ship, and at least a portion of a first air discharge period of the first air discharge part and at least a portion of a second air discharge period of the second air discharge part overlap each other.

Abstract: A frictional resistance-reducing device and a ship including the same are disclosed. The ship comprises: an outer panel including and air outlet; a plurality of reinforcement members provided on the inner surface of the outer panel so as to be spaced from each other; and a frictional resistance-reducing device formed on the inner surface of the out panel between immediately neighboring reinforcement members among the plurality of reinforcement members, so as to cover the air outlet, wherein the frictional resistance-reducing device includes: a hollow housing of which one surface is opened; and an air inlet formed in the housing, and the opened one surface faces the air outlet.

Abstract: Disclosed are a frictional resistance reducing device that effectively reduces the frictional resistance of a ship, and a ship including same. The frictional resistance reducing device comprises: a first air discharge part formed on the leading undersurface of a ship and discharging air into water, a second air discharge part formed behind the first air discharge part and discharging air into water; and an air supplying source supplying air to the first air discharge part and the second air discharge part, wherein the first air discharge part and the second air discharge part are disposed in-line along the lengthwise direction of the ship, and at least a portion of a first air discharge duration of the first air discharge part and at least a portion of a second air discharge duration of the second air discharge part overlap each other.

Abstract: A frictional resistance-reducing device and a ship including the same are disclosed. The ship comprises: an outer panel including and air outlet; a plurality of reinforcement members provided on the inner surface of the outer panel so as to be spaced from each other; and a frictional resistance-reducing device formed on the inner surface of the out panel between immediately neighboring reinforcement members among the plurality of reinforcement members, so as to cover the air outlet, wherein the frictional resistance-reducing device includes: a hollow housing of which one surface is opened; and an air inlet formed in the houseing, and the opened one surface faces the air outlet.

Abstract: The present disclosure is related to a power control apparatus and a method for controlling power, more specifically to a power control apparatus that controls the risk of overcurrent in a power generator when the voltage in the power grid is low. In accordance with an embodiment of the present disclosure, a power control apparatus that controls power in a power generation system including a generator generating power can include a current comparator, which calculates an error current by using a difference between a current measured at the generator and a rated current of the generator, a controlling unit, which calculates a real power value by receiving the error current and outputs a switch driving signal corresponding to the calculated real power value, a switch, which is operated by the switch driving signal, and a resistance device, which is coupled to the switch to consume the error current.

Abstract: The present disclosure is related to a power control apparatus and a method for controlling power, more specifically to a power control apparatus that controls the risk of overcurrent in a power generator when the voltage in the power grid is low. In accordance with an embodiment of the present disclosure, a power control apparatus that controls power in a power generation system including a generator generating power can include a current comparator, which calculates an error current by using a difference between a current measured at the generator and a rated current of the generator, a controlling unit, which calculates a real power value by receiving the error current and outputs a switch driving signal corresponding to the calculated real power value, a switch, which is operated by the switch driving signal, and a resistance device, which is coupled to the switch to consume the error current.

Abstract: The present disclosure is related to a power control apparatus and a method for controlling power, more specifically to a power control apparatus that controls the risk of overcurrent in a power generator when the voltage in the power grid is low. In accordance with an embodiment of the present disclosure, a power control apparatus that controls power in a power generation system including a generator generating power can include a current comparator, which calculates an error current by using a difference between a current measured at the generator and a rated current of the generator, a controlling unit, which calculates a real power value by receiving the error current and outputs a switch driving signal corresponding to the calculated real power value, a switch, which is operated by the switch driving signal, and a resistance device, which is coupled to the switch to consume the error current.

Abstract: This invention relates to a board-shaped wideband dual polarization antenna whose feeding structure is simplified. Dipole antennas are prepared on both front and rear surfaces of a printed circuit board, and an electric signal is fed to the dipole antennas through via holes at the same time. Through the dipole antennas, the dual polarization antenna radiates dual polarized waves whose radiation emissions have perpendicular directions to each other. The wideband characteristics of the dual polarization antenna are improved through parasitic elements.

Abstract: The present disclosure is related to a power control apparatus and a method for controlling power, more specifically to a power control apparatus that controls the risk of overcurrent in a power generator when the voltage in the power grid is low. In accordance with an embodiment of the present disclosure, a power control apparatus that controls power in a power generation system including a generator generating power can include a current comparator, which calculates an error current by using a difference between a current measured at the generator and a rated current of the generator, a controlling unit, which calculates a real power value by receiving the error current and outputs a switch driving signal corresponding to the calculated real power value, a switch, which is operated by the switch driving signal, and a resistance device, which is coupled to the switch to consume the error current.