Abstract: A pre-coating filter device includes: a filtration tank comprising a raw water inlet through which raw water flows on one side, and a drain port at the bottom; a top cover coupled to the upper part of the filtration tank and comprising a coupling hole through the middle part; a purified water discharge pipe coupled to the coupling hole of the top cover; a purified water storage space unit coupled to the lower part of the top cover and located within the filtration tank, and comprising a communication pipe connected to the central part; a filter coupling plate body coupled to the lower part of the purified water storage space unit and comprising a plurality of coupling holes through; and a pre-coating filter coupled to the coupling hole of the filter coupling plate body.

Abstract: The present disclosure relates to a wireless communication system of an intelligent unmanned aerial vehicle (UAV), which may perform real-time communication between an intelligent UAV in air or in water and a ground control station by using visible light communication.

Abstract: A pre-coating filter device includes: a filtration tank comprising a raw water inlet through which raw water flows on one side, and a drain port at the bottom; a top cover coupled to the upper part of the filtration tank and comprising a coupling hole through the middle part; a purified water discharge pipe coupled to the coupling hole of the top cover; a purified water storage space unit coupled to the lower part of the top cover and located within the filtration tank, and comprising a communication pipe connected to the central part; a filter coupling plate body coupled to the lower part of the purified water storage space unit and comprising a plurality of coupling holes through; and a pre-coating filter coupled to the coupling hole of the filter coupling plate body.

Abstract: Provided is a capacitor, which includes a first electrode including aluminum, a second electrode facing the first electrode, and a first dielectric layer interposed between the first electrode and the second electrode, including aluminum oxide, and having multiple pores defined in a surface of the first dielectric layer in contact with the second electrode.

Abstract: The present specification relates to a conductive structure body and a manufacturing method thereof.

Abstract: Provided is a capacitor, which includes a first electrode including aluminum, a second electrode facing the first electrode, and a first dielectric layer interposed between the first electrode and the second electrode, including aluminum oxide, and having multiple pores defined in a surface of the first dielectric layer in contact with the second electrode.

Abstract: Provided are an underwater communication device using visible light and an underwater communication method using the same. The underwater communication device using visible light, includes: an input unit converting a data signal received from the outside under water into an electrical signal; a transmitting unit converting the electrical signal into a visible light signal and emitting the visible light signal under water; a receiving unit recognizing the visible light signal under water and converting the visible light signal into the electrical signal; and an output unit converting the electrical signal into a data signal and outputting the data signal under water. Therefore, it is possible to provide an underwater communication device that may be implemented at low cost, perform wide band communication, and have excellent security.

Abstract: Provided is a communication system using a near field and a method thereof, which uses a conductive medium, i.e., a human body, and comprises a plurality of peripheral devices having a communication device for transmitting and receiving a predetermined data signal through the near field formed around the human body, using a carrier sense multiple access with collision detection (CSMA/CD) method, thereby solving a directional problem of an antenna when the wireless system is used and achieving miniaturization, as well as enhancing communication efficiency by using the most appropriate frequency to the human communication without collision of transmitting and receiving signals between the plurality of peripheral devices.

Abstract: Provided is a frequency converter that can remove a DC offset and suppress spurious response and intermodulation. The frequency converter receives a reference signal and a local oscillator signal and outputs a frequency component corresponding to the sum or difference of the reference signal and the even-order harmonics of local oscillator signal. The frequency converter includes a reference signal input part including a pair of MOS transistors connected in a differential amplifier form, which have gates to which positive and negative reference signals having a differential phase difference therebetween are respectively input, and first, second, third and fourth frequency conversion parts each of which is connected to the reference signal input part and includes a pair of MOS transistors. Local oscillator signals having a differential phase difference therebetween are input to the gates of the MOS transistors of the first and second frequency conversion parts.

Abstract: There is provided a predistortion linearizer for suppressing the gain and phase distortions in a power amplifier arranged between input and output stages including a transistor which is arranged between the input stage and the power amplifier and has a base-emitter junction diode, and a resistor arranged in series between the transistor and the power amplifier.

Abstract: Provided is a dual antenna diversity transmitter and system having improved power amplifier efficiency, and further comprising switches in the dual antenna diversity transmitter and system, to minimize a DC input power consumed by the power amplifier depending on the required transmitting output power and operate efficiently the power amplifier, whereby signal linearity can be maintained and the power amplifier can be efficiently operated in a more simplified manner, as compared to the conventional high efficiency power amplifier.