Abstract: The present invention relates to a vertical alignment layer including a cyclic olefin copolymer, and more specifically, the present invention relates to a vertical alignment layer capable of having alignment even in a low temperature process, and exhibiting excellent liquid crystal vertical alignment by including a cyclic olefin copolymer having a specific substituent.

Abstract: The present invention relates to a solar cell and a manufacturing method therefor. According to the manufacturing method, a highly efficient perovskite solar cell can be manufactured by inducing a spontaneous formation of a recombination preventing layer using the organic halide and the metal halide at a specific molar ratio.

Abstract: A wireless power transmission system based on cell division is provided. A communication and power control method of the wireless power transmission system, includes setting a magnetic coupling zone. The method further includes detecting a target device in the magnetic coupling zone. The method further includes transmitting a power to the target device. The method further includes adjusting an amount of the power based on a transmission efficiency of the power.

Abstract: There are provided a photoreactive copolymer and an alignment layer comprising the same, and more particularly, to a photoreactive copolymer including a copolymer of two different kinds of monomers, and an alignment layer comprising the same. The photoreactive copolymer according to the present invention may have excellent liquid crystal alignment property and alignment speed, easily change an alignment direction depending on a polarization direction, and have excellent solubility to an organic solvent, such that the photoreactive copolymer may be used in various fields such as a liquid crystal device, and the like.

Abstract: An apparatus and method for communication using a wireless power are provided. The apparatus includes an amplifier configured to amplify an input signal based on a power supplied to the amplifier. The apparatus further includes a control unit configured to detect a change in an impedance of a target device, and to change the power based on the change in the impedance. The apparatus further includes a demodulation unit configured to receive a message from the target device, and to demodulate the message based on the changed power.

Abstract: The present invention relates to an organic/inorganic hybrid perovskite having a novel structure which can be used as an absorber of a solar cell, a method for preparing the same, and a solar cell comprising the same. The compound according to the present invention has a perovskite structure into which deuterium is introduced, thereby exhibiting high humidity and light stability, and thus can be useful as an absorber of a solar cell.

Abstract: A wireless power transmission system and a method for increasing a coupling efficiency by adjusting a resonant frequency are provided. A device of the wireless power transmission system includes a resonator configured to transmit a wireless power, and a communication unit configured to receive information from another device. The device further includes a controller configured to determine a power transmission efficiency based on the information, and adjust a resonant frequency of the device, a resonant frequency of a relay device, and a resonant frequency of the other device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency.

Abstract: There are provided a novel cyclic olefin compound having a photoreactive group and a photoreactive polymer. The cyclic olefin compound is applicable to various photoreactions, such as of liquid crystal alignment layers and can be preferably used as a precursor of various organic compounds or polymers.

Abstract: A wireless power transmitter includes a source resonator configured to wirelessly transmit power via magnetic coupling with a target resonator; and an impedance adjusting unit configured to adjust an impedance of the source resonator using a plurality of impedance-matching bars located in the source resonator.

Abstract: An overvoltage protecting unit and an overcurrent protecting unit protect a power device from an overvoltage and an overcurrent using a comparator having hysteresis. An overtemperature protecting unit protects the power device from an overtemperature using a thermistor having a resistance that changes as a temperature of the thermistor changes.

Abstract: A wireless power transmission system and a method for increasing a coupling efficiency by adjusting a resonant frequency are provided. A device of the wireless power transmission system includes a resonator configured to transmit a wireless power, and a communication unit configured to receive information from another device. The device further includes a controller configured to determine a power transmission efficiency based on the information, and adjust a resonant frequency of the device, a resonant frequency of a relay device, and a resonant frequency of the other device, if the power transmission efficiency is less than or equal to a predetermined reference efficiency.

Abstract: A resonance power transmission system for controlling a supply voltage of a power converter based on power transmission efficiency is provided. According to an aspect, a resonance power transmitter configured to transmit resonance power to one or more resonance power receivers may include: a voltage controller configured to receive an input signal and to output voltage of a predetermined level; a source controller configured to control a signal level of the DC voltage based the number of resonance power receivers.

Abstract: The present invention relates to a vertical alignment layer including a cyclic olefin copolymer, and more specifically, the present invention relates to a vertical alignment layer capable of having alignment even in a low temperature process, and exhibiting excellent liquid crystal vertical alignment by including a cyclic olefin copolymer having a specific substituent.

Abstract: A resonance power transmission system for controlling a supply voltage of a power converter based on power transmission efficiency is provided. According to an aspect, a resonance power transmitter configured to transmit resonance power to one or more resonance power receivers may include: a voltage controller configured to receive an input signal and to output voltage of a predetermined level; a source controller configured to control a signal level of the DC voltage based the number of resonance power receivers.

Abstract: An apparatus and method of using near field communication (NFC) and wireless power transmission (WPT) are provided. A power receiving apparatus includes a resonator configured to receive a power and to output the power. The power receiving apparatus further includes a near field communication (NFC) receiver configured to perform wireless communication using the power output by the resonator. The power receiving apparatus further includes a wireless power transmission (WPT) receiver configured to supply a voltage using the power output by the resonator. The power receiving apparatus further includes a connecting unit configured to selectively connect the resonator to either the NFC receiver or the WPT receiver. The power receiving apparatus further includes a mode selector configured to control the connecting unit to selectively connect the resonator to either the NFC receiver or the WPT receiver based on the power output by the resonator.

Abstract: A high efficiency variable power transmitting apparatus outputs a variable power by modulating, with respect to a time axis, a high frequency signal having a constant amplitude by turning the high frequency signal ON and OFF, amplifying the variable power to satisfy a requested power level of a target device based on a supply voltage having a predetermined level, converting an alternating current (AC) voltage received from a power source to a direct current (DC) voltage, generating the supply voltage having the predetermined level based on the DC voltage, and providing the supply voltage having the predetermined level to the PA.

Abstract: A wireless power transmission system, and a method of controlling power in the wireless power transmission system based on a detection parameter are provided. The method includes transmitting a request signal to a device. The method further includes receiving, from the device, a response signal corresponding to the request signal, the response signal including a parameter of the device. The method further includes generating an operation power based on the parameter of the device, the operation power being used for an operation of the device.

Abstract: An apparatus and method of using near field communication (NFC) and wireless power transmission (WPT) are provided. A power receiving apparatus includes a resonator configured to receive a power and to output the power. The power receiving apparatus further includes a near field communication (NFC) receiver configured to perform wireless communication using the power output by the resonator. The power receiving apparatus further includes a wireless power transmission (WPT) receiver configured to supply a voltage using the power output by the resonator. The power receiving apparatus further includes a connecting unit configured to selectively connect the resonator to either the NFC receiver or the WPT receiver. The power receiving apparatus further includes a mode selector configured to control the connecting unit to selectively connect the resonator to either the NFC receiver or the WPT receiver based on the power output by the resonator.

Abstract: A communication apparatus in a wireless power transmission system includes an operating mode converter configured to switch an operating mode of the communication apparatus between a transmitting mode and a receiving mode according to a predetermined timing; and a transmitting unit configured to transmit state information of a channel occupied by a source including the communication apparatus using a continuous wave signal while the communication apparatus is operating in the transmitting mode irrespective of whether the communication apparatus is performing communication via the occupied channel. The source including the communication apparatus is configured to transmit wireless power. The occupied channel has been assigned to the source including the communication apparatus from a plurality of channels available in a communication cell for assignment to a plurality of sources each configured to transmit wireless power.

Abstract: Provided is a wireless power transmission apparatus and method. The wireless power transmission apparatus may include a coupling unit to couple a reflected signal with respect to a transmitted resonance power, and a resonance point detecting unit to scan a frequency of the reflected signal to detect a resonance point. A resonance frequency of the source resonator may be controlled using the detected resonance point.