• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.717-718
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• 2013

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.6
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• pp.275-280
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• 2010

Recently, This paper suggests that LED-ID technique applying positioning method for LED light. also, Authors in this paper has launched this investigation earnestly. However, there are various interferences such as MPI(Multi Path Interference) by reflected waves of the surface and interfere factors by their correlation properties of the ID in LED-ID wireless channel. Therefore, in this paper, we propose a novel OOK(On-Off Keying)-CDMA(Code Division Multiple Access) system using unipolar ZCD(Zero Correlation Duration) spreading code and verify the availability of the proposed system via the evaluation performance simulation.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.6
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• pp.17-23
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• 2012

In this paper, we were proposed a new LED light device lighting control algorithm for optimal energy saving. The propose lighting control algorithm be to the LED lights devices lighting control by measuring illuminance into multi sensors. And it be to lighting control by inverting of octagon pattern during set-up time. All the LED is lighting when detecting motion by the motion sensor. And, it was designed enable remote management control by communicate with central monitoring center using Zigbee wireless network to measured data from sensors at real time. In this paper, a proposed lighting control algorithm was measured power consumption about the lighting status of LED lighting device using the lighting control program for demonstrate of energy savings effect. The measured result, the lighting method applying proposed algorithm were proved energy savings effect of more 40% more compared to the existing lighting method.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.433-438
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• 2012

With technologies available now, there are only a few virtual objects that augmented reality content can create. So, wider application of it is limited. If people want to realize any augmented reality content, out of a vast amount of materials available as well as virtual objects, the number of virtual objects that markers can render should be made to go up along with the content. In a precedent study, IR LEDs markers render marker information following On-Off signals. The number of LEDs should be raised to render as much information as possible, subsequently leading to the problem of oversized markers. This problem can be solved by generating data signals through the blinking of LEDs. This research puts forward OOK Code algorithm that represents the mode of data transmission using the light of LEDs. The amount of information that can be rendered by a marker increases and the size of the marker gets smaller, which is a merit, when it receives data signals from light.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.10B
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• pp.1258-1267
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• 2011

In this paper, using the indoor LED-ID communication system have researched for how to transmit video signals. In LED-ID communications use the LEDs for lighting features at the same time communication is an effective way to implement. This proposed system using Visible light(RGB) as way to transmit signals, depends on the mixture RGB, which decided the color of light, moreover, each things determined their performance. However, if the video signal were fixed allocated RGB to transmit such as the original system, the importance of the each signals a different occur the limit on the quality of the video than SVC signals. In order to solve this problem in this paper, according to the RGB mixture ratios analyze the performance for the White LED, which analyzed based on allocating the SVC signal by transmitting to improve the quality of the video was about how researched.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.1
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• pp.42-50
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• 2016

Recently, researches about the communication between LED array and the camera (alias 'Visual-MIMO'), have been actively conducted, and the application to the vehicle and a smart phone is expected to be maximized. Since the bit error may occur if the ISI is severe in a LED array, it is necessary to switch from the multiplexing to the diversity mode. In this paper, according to the use or not of a reference array pattern, a method for determining the transition time to the diversity mode is suggested and verified. When using the reference pattern, it determines the transition time to the diversity mode from the multiplexing using the brightness information of the received image. If the reference array pattern is not used, the size of LED array compared to the entire image according to the distance is used and the size of the LED array at the distance of a severe ISI may be used for the determination of transition time to the diversity. Finally, the proposed method is verified through the simulation and hardware experiments as well as by analyzing the performance in accordance with the ISI level and the distance.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.4
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• pp.275-283
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• 2021

In this study, a driver IC for an AC-powered LED that can be manufactured with a low voltage semiconductor process is designed and the performances of the driver IC were simulated. In order to manufacture a driver IC that operates directly at AC 220V, a semiconductor manufacturing process that satisfies a breakdown voltage of 500V or higher is required. A semiconductor manufacturing process for a high-voltage device requires a much higher manufacturing cost than a general semiconductor process for a low-voltage device. Therefore, the LED driver IC is designed in series so that it can be manufactured with semiconductor process technology that implements a low-voltage device. This makes it possible to divide and apply the voltage to each LED block even if the input voltage is high. The LED lighting circuit shows a power factor of 96% at 220V. In the pnp transistor circuit, a very high power factor of 99.7% can be obtained, and it shows a very stable operation regardless of the fluctuation of the input voltage.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1349-1354
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• 2021

An All-in-one LED lantern is a light device to determine the fairway of ships in operation. The current all-in-one LED lantern powered by solar energy is challenged by insufficient power capacity due to limited sun hours. This article presents an all-in-one 9-Nautical mile LED lantern driven by solar and wind power that is abundant maritime renewable energy. Furthermore, the remote smart monitoring system is developed. A smart control system capable of remote control of the lantern was implemented by using the LED lantern device and monitoring system as IoT. This technology that realtime condition monitoring and remote control are developed for safe ship navigation. We expect that maintaining the accuracy and consistency of LED lanterns prevents marine accidents and reduces social costs.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.391-392
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• 2008

A SPICE-based 3-dimensional circuit model of Light-Emitting Diode(LED) was modified include the reverse breakdown properties. The new model is found to be accurate to study the failure mechanisms of LEDs under electrostatic discharge (ESD) and electronic overstress (EOS). It was found that the permanent damages under heavy reverse stress is mainly due to the high electric field strength in P-GaN layer.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.2
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• pp.169-174
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• 2014

This paper proposes a novel beehive-shaped reflector for application to light-emitting diode (LED) transceivers for illumination and bi-directional visible light communication (VLC). By using a diffuse propagation model extended to line-of-sight and direct signals, the distribution of illuminance and the path loss of the transceiver are investigated to evaluate the performance of the beehive-shaped reflector. To verify bi-directional communication, a VLC-based image capture system, comprising a complementary metal-oxide semiconductor (CMOS) image sensor and video processor unit, is demonstrated. Real-time images captured by the CMOS camera are successfully transmitted to the monitoring system via a free-space channel at a rate of 115.2 kbps.