• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.487-495
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• 2017

The thermal characteristics of the electrodeless lamp are one of the main factors that determine the design and performance of the lamp. The coupler changes the impedance characteristic by heat and its use temperature is usually within about $150^{\circ}C$. In this study, we observed the phenomenon when the coupler was exposed at a temperature of $150^{\circ}C$ or higher, which has not been discussed so far. Two types of coupler A and coupler B with different spacing between the inner tube and the coupler were analyzed for electrical, thermal and optical properties and deterioration characteristics with different heat and heat shielding conditions. First, the impedance of the system is obtained and used as a criterion for analyzing the electrical characteristics through it. The diameters of the two types of couplers are 1 mm, and the experimental result shows that the coupler diameter is 1 mm, which can cancel out the loss of the magnetic field strength. Therefore, based on these results, when the coupler is exposed to high temperature of about $200^{\circ}C$, the efficient design method corresponding thereto is proposed.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.2
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• pp.68-78
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• 2001

UV-curable resin has the properties of quick-drying, thigh productivity at low temperature, energy savint, space saving, solventless, non-polluting and low-stinking, and thus, UV-curing system has been widely used in the fields of printing inks, adhesives, paints and coating agents. This study has been executed to micro-patterning used UV-curable resin, The micro-patterning properties of this photoresist were investigated under irradiation of UV light low pressure mercury lamp. When the exposed photoresist film was developed by pure water developer, the resolution of this photoresist was about 50$\mu\textrm{m}$.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.5
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• pp.615-622
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• 2015

As the development of high efficiency and high flux density LEDs, the trend of illumination lamp industry transfers from conventional-lamps to the LED-lamps. For energy efficiencies, LED lamps are superior to the conventional lamps, but they have heat problems. Especially, the heat problems are severe for the high luminance lamps. They degrade the soldering point of the metal PCB, and shorten the life cycle of LEDs. So, the solution of the heat sinking is very important to develop high luminance LED lamps. This study suggested a new method to solve the heat problems for high luminance LED lamps, and developed a LED lamp which has 1200W power. In this study, a water jacket is installed to the LED lamp, and the cooing water is circulated by a water pump.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.477-486
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• 2017

For the analysis of the optical characteristics of electrodeless lamps, all the lamp surface temperatures have been treated the same. However, the interpretation of optical properties in this way has not been sufficient in terms of accuracy. In this paper, to overcome this problem, we divided the inside of the bulb into two parts, hot spot and cold spot, and analyzed the density difference of mercury by different temperatures. Here, it is assumed that the distribution of temperature and density is linear. The effect of optical characteristics through redistribution of hot spot and cold spot density was analyzed. It was also confirmed that the ratio of the density of the redistributed discharge gas has a great influence on the saturation of the optical characteristics. Therefore, it is proved that the design method through the domestic setting is very useful in the actual design, and the method for shortening the time for stabilizing the optical characteristics is obtained.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.643-648
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• 2011

In this study, SMPS driven LED traffic signal light for Large-scale traffic such as railroad and airport was designed and its electrical and EMI characteristics were measured. The output current of the LED module driven by SMPS was 1.67A for AC and DC input voltage over 10V. The conducted emission measured over 0.15~30MHz frequency range was lower than the allowed quasi-peak and average level, and the radiated noise measured over 30~1000MHz frequency range showed $23.96dB{\mu}V/m$ at 59.96MHz.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.124-132
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• 2023

In this paper, we present a simple classification model based on statistical features and demonstrate the successful implementation of a brain-computer interface (BCI) based light on/off control system. This research shows study and development of light on/off control system based on BCI technology, which allows the users to control switching a lamp using electroencephalogram (EEG) signals. The logistic regression algorithm is used for classification of the EEG signal to convert it into light on, light off control commands. Training data were collected using 14-channel BCI system which records the brain signals of participants watching a screen with flickering lights and saves the data into .csv file for future analysis. After extracting a number of features from the data and performing classification using logistic regression, we created commands to switch on a physical lamp and tested it in a real environment. Logistic regression allowed us to quite accurately classify the EEG signals based on the user's mental state and we were able to classify the EEG signals with 82.5% accuracy, producing reliable commands for turning on and off the light.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1810-1814
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• 2006

In this paper, the brightmess from inside gas pressure, applied voltages, and operation frequency conditions was measured and the discharge characteristics in FFL(Flat Fluorescent Lamp) also were measured and discussed. The brightness and lifetime after vacuum exhaust ($350^{\circ}C$ and 1 hour) ate remarkably developed. When the gas pressure of lamp-inside is high, the brightness is also increased automatically. But for the stabilization of operation and driving voltage, the highest values of brightness at about 1000[V], 300[Torr] and 64(kHz) are measured and the results are shown as the optimized driving conditions for FFL.

• Proceedings of the KIEE Conference
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• 2004.04a
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• pp.163-165
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• 2004

A low-cost electronic ballast using a conventional HID controller IC is proposed. The proposed ballast consists of high frequency DC-DC converter, low frequency DC-AC inverter, and igniter circuit. This ballast shows hot-restrike, suitable operation at each stage of various lamp state and stable operation in steady-state.

• Journal of the Korea Society of Computer and Information
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• v.25 no.3
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• pp.89-96
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• 2020

Solar lamp systems may not operate normally in the event of some system or controller failure due to internal or external factors, in which case secondary problems occur, which may cost the system recovery. Thus, when these errors occur, a technology is needed to recover to the state it was in before the failure occurred and to enable re-execution. This paper designs and implements a system that can recover the state of the system to the state prior to the time of the error by using the Watchdog Timer within the controller if a software error has occurred inside the system, and it also proposes a technology to reset and re-execution the system through a separate reset circuit in the event of hardware failure. The proposed system provides stable operation, maintenance cost reduction and reliability of the solar lamp system by enabling the system to operate semi-permanently without external support by utilizing the automatic recovery and automatic reset function for errors that occur in the operation of the solar lamp system. In addition, it can be applied to maintain the system's constancy by utilizing the self-operation, diagnosis and recovery functions required in various high reliability applications.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.549-554
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• 2007

In this paper, the luminance and resistance from different electrode materials of external electrode fluorescent lamp are measured and analyzed. New materials and process technology of external electrode are very important for the developed characteristics in lamp fabrication. This experiment, three different types for the forming of external electrode are Cu and Al taping, silver paste, Ni and Cu electrode-less plating methods. In the measurement of luminance, the results of brightness by Ni and Au plating methods for the external electrode on lamp glass are presented and also compared with the results by the methods using different electrode materials. The measured resistance values of Ni and Au plating process showed a little bit higher than that of silver paste process in spite of developed results of brightness. The Ni and Ni/Au plating processes are demonstrated best results and also showed a little bit different brightness due to different previous surface etching treatments.