Abstract:
An inverter apparatus having a power supply circuit includes a converter circuit for rectifying AC power into DC power, a smoothening circuit for smoothening the rectified DC power, an inverter circuit for converting the smoothened DC into AC at a variable frequency through a plurality of switches to control a load, and a current detection circuit for detecting overcurrent from the smoothened DC supplied from the inverter circuit, wherein the inverter circuit applies bootstrap power for driving the switches to the current detection circuit to use the bootstrap power as power of the current detection circuit. When bootstrap power for driving switch gates is used, it is possible to use the bootstrap power as the power of the current detection circuit by adding the auxiliary circuit composed of a small number of passive elements.
Abstract:
The present invention relates to an image display apparatus and method for displaying a three-dimensional (3D) image capable of interacting with a user, and provides a 3D image display apparatus and method that may interact with a user by reproducing a 3D image, generated by a conventional volume display apparatus, at a position different from a position at which the 3D image is generated, and by modifying and playing the reproduced 3D image based on a motion of the user. Also, the present invention enables the user to realistically interact with the 3D image by stimulating tactile sensation of the user through ultrasound.
Abstract:
A patch antenna having a single patch fed with multiple signals is provided. The patch antenna includes: a first patch; a first feeder and a second feeder which are connected to the first patch; and a second patch which is parallel to the first patch. Accordingly, since multiple signals can be fed into a single patch, a MIMO antenna can be embodied by using a patch antenna which has high isolation between feeders without increasing its size.
Abstract:
A method and system for detecting a fault of a serial coil type permanent magnet motor includes driving the motor based on a predefined current reference value, detecting a phase current vector of the motor, and calculating a current compensation value for removing a negative sequence component of the motor based on the phase current vector. The current compensation value is provided to a negative sequence current controller for calculating a faulty phase and a degree of a fault of the motor using the output of the negative sequence current controller and a fault model to which induced magnetic flux variations in a specific slot of a specific faulty phase of the motor and other slots of the same phase as the specific phase are applied, and applying a current reference value to which the calculated faulty phase and degree of fault are applied.
Abstract:
A down-frequency conversion circuit and up-frequency conversion circuit, and a receiver and transmitter applying the same are provided. The down-frequency conversion circuit includes a harmonic mixer and general mixer, and thus becomes able to convert frequency using one LO (Local Oscillator) frequency, thereby reducing burden on generating LO frequency.
Abstract:
Provided herein is a communication system and method capable of performing visible light communication and optic networking, the system performing visible light communication with an electronic device inside a vehicle and accessing an optic network inside the vehicle. Accordingly, RF interference and distortion is removed, and thus not effecting use of a wireless device inside the vehicle, thereby reducing malfunction/error of a electronic control device and enabling real time data transceiving in the vehicle.
Abstract:
The vehicle AVM system according to an exemplary embodiment of the present disclosure includes a first camera network constructed of some of the cameras configuring the AVM system; a second camera network constructed of some of the cameras configuring the AVM system; and a processor configured to create a first image from the images created by the cameras configuring the first camera network, and to create a second image from the images created by the cameras configuring the second camera network. Accordingly, by installing more number of cameras in an AVM system of a vehicle than the number of cameras in a general vehicle and thus removing dead zones according to vehicle characteristics, it becomes possible to perform smooth networking and prevent image delay, thereby preventing accidents due to dead zones and image delay.
Abstract:
The present invention relates to an adaptive frequency hopping apparatus in a wireless personal area network (WPAN) system, wherein predetermined packets of data can be correctly transmitted by estimating the channel qualities of operating bands in advance and transmitting the packets through a proper band. The adaptive frequency hopping apparatus according to the present invention comprises a frequency table for monitoring each channel quality and storing and outputting information on each channel quality accumulated therein, a frequency hopping transceiver for generating and outputting a frequency pattern in accordance with predetermined rules, a link controller for generating an asynchronous connectionless (ACL) link in accordance with output signals of the frequency table and the frequency hopping transceiver and controlling selection of an operating mode between a channel avoidance scheme and a channel selection scheme, a packet handler for generating packet data by integrating a synchronous connection oriented (SCO) link and the ACL link inputted thereinto, a gaussian frequency shift keying (GFSK) modulator for performing GFSK modulation for signals outputted from the packet handler, a mode selector for selecting the operating mode between the channel avoidance scheme and the channel selection scheme in accordance with output signals of the frequency hopping transceiver and the link controller, a frequency synthesizer for synthesizing frequencies in accordance with output signals of the mode selector, a first multiplier for multiplying signals from outputted from the frequency synthesizer and the GFSK modulator and for outputting the multiplied signals as transmission signals, a second multiplier for multiplying the output signals of the frequency synthesizer by received signals, an RSSI detector for detecting a RSSI from output signals of the second multiplier, a GFSK demodulator for performing GFSK demodulation for the output signals of the second multiplier, a packet handler for restoring packet-type data from output signals of the GFSK demodulator, and a channel quality detector for estimating the channel quality by using the output signals of the RSSI detector and the packet handler, and storing it in the frequency table.
Abstract:
A method of modeling a hybrid sensor is proposed. The method may include receiving information on at least one physical sensor that is disposed within a target space, disposing at least one virtual sensor within the target space, and obtaining sensing data of the virtual sensor and converting the sensing data into visualization information. The method may also include analyzing matching between an additionally disposed physical sensor and the virtual sensor when the physical sensor is additionally disposed at a location of any one of the disposed virtual sensors. The method may further include correcting the weight of the sensing data of the virtual sensor based on results of the analysis of the matching.
Abstract:
Provided are AI-based optimal operation number control system and method for increasing operation efficiency of industrial boilers. A boiler control method according to an embodiment includes: collecting operation data of boilers; deriving operating boiler combinations by inputting the collected operation data to an AI model that is trained to receive operation data and to derive operating boiler combinations; and controlling operation of the boilers according to the derived operating boiler combinations. Accordingly, by analyzing operating conditions changeable according to a schedule of the field and using the operating conditions for deriving a control value, operation efficiency of industrial boilers are increased.