• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.511-512
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• 2006

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.7
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• pp.19-25
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• 2014

In the LED lighting applications, because LED packages are the origin of heat generation, there are thermal design problem on heat sinks. In the thermal design, it is important to consider the total volume and the total weight of heat sink simultaneously. In this study, an Al 6063 heat sink was optimized using Computational Fluid Dynamics(CFD) simulation tool for the cooling of 30W LED module, and then the cooling performance and the total weight of heat sinks with Al 6063 and Thermal Conductive Polycarbonate(TCP) were compared under the same conditions. As the result of simulation, an Al 6063 heat sink was optimized with 22 ea. of fins and 1.6 mm of fin thickness. LED Junction Temperature of the TCP Heat Sink was $5.6^{\circ}C$ higher, but total weight of it was 47 % less than the Al 6063.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.10
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• pp.771-777
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• 2013

This paper dealt with the development of a LED floodlight for naval vessels to replace the conventional floodlight using an incandescent and a halogen lamp. We found a technical solution for current problems of conventional lights and also improved optical characteristics by developing a LED floodlight which has a typical long-lived light source with high efficiency. To satisfy the requirements specified in Korea Standard Vessels (KS V), the optical structure was designed with selected LED package and lens. A LED module was composed of 10 LEDs in series for stable luminous output, and an aluminium heat sink was adopted for effective heat-radiation design. The LED floodlight was fabricated as a module type so that it can easily replace the conventional light source. The power consumption of the prototype floodlight was only a tenth of a conventional one with the same optical performance. Also, a test showed the floodlight satisfied the electrical, optical and environmental requirements of the standards.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2317-2322
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• 2010

Market for LED lights as a newly-growing industry has been growing, and secureness of high efficiency and long life through optimal thermal design are crucial for further popularization. In this study, considerable improvement in thermal performance for a 10W LED light has been done compared to a previous model. For this, numerical model has been established through experiments and used to optimize design factors in heat release such as fin shape, PCB kind or LED number etc. Furthermore, prototype of a LED light has been made and the improved thermal performance was verified with heat release experiments.

• Journal of IKEEE
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• v.23 no.2
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• pp.364-369
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• 2019

The ratios of compliant branch circuit of leakage current and insulation resistance were 68.4% and 90.8%, respectively at the lamp load, 64.6% and 96.5% at the heat load, 86.7% and 88.9% at the power load. Limit of residual current of the zero phase secondary current value at the zero phase primary current was 100 A when rated primary current 400 A more than. The reason why the ratio of branch circuit of the leakage current was less than the ratio of compliant branch circuit of the insulation resistance might be that the leakage current includes the capacitive leakage current and the zero phase current.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.18-25
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• 2002

In this paper, We have researched about the Electronic Ballast for 250W HPS(High Pressure Sodium) lamp. This Electronic Ballast is capable to operate the Ignition and Steady State Using the Class D LCC resonant tank, and minimizing the full-bridge inverter's Switching Stress by implementation Quasi-square ZC-ZVS Soft Switching Method. And also, We have reduced the heat of MOS-FETs and high frequency switching surge noise using the RCD damp snubber. Therefore, We are sure that the developed ballast has the properties of the stable & reliable Control and the function of minimizing the total noise of the system.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.653-655
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• 1992

Longitudinal and transverse normal zone propagation in the superconducting coil are analyzed and propagation velocity is derived from the heat balance equations in the propagating boundary region. Transverse velocity is nearly $10^{-2}$ order of longitudinal velocity. Propagation velocity ie linearly proportional to the transport current. Increasing lamp current speeds up longitudinal velocity by 0.279 m/s under the applied field of 2T. Transient heat transfer has a significant effect on normal zone propagation velocity and it decreases longitudinal velocity by 4.2 m/s under the applied field of 2T as being compared to steady-state heat transfer.

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.208-209
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• 2005

The gradient of the residual stress distribution by the heat treatment temperature in the commercial single mode fiber was investigated. The heat treatment of the optical fiber was carried out at 700${\circ}$C, 1100${\circ}$C, and 1200${\circ}$C for 1 hour by using the halogen lamp and the residual stress measurement of the optical fiber was accomplished by using the inverse linear polarizing method. Mechanical residual stress was relaxed and thermal residual stress was invested by the heat treatment.

• 전자공학회논문지 IE
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• v.48 no.2
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• pp.12-18
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• 2011

In this paper, did numerical simulation to confirm LED module for lighting and protection against heat special quality of heat sink device. Analysis was gone dividing on case that emitting light side turns normalcy department considering that eat of device according to usage and case that turn down looking being street lamp of 200 W or security appointment lighting device analysis case, and also, volume of thermal element divides on big case and small case and analyzed. Confirmed that can do so that may discharge LED's thermal value to outside enough in analysis wave and current heat sink shape, and investigated that difference of protection against heat performance according to position of device and size of thermal element appears.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.1
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• pp.24-34
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• 2013

This paper introduces the study of hood-type wind turbine embedded on highway median strip. Recently, many studies are being made to apply to small wind turbine in city. This study is wind turbine producing electricity generated from the wind by running cars. In order to analyze wind generated by running cars, we measured experiments using running cars and buses. Also, using CFD and interpreter program, we analysis wind turbines performance and applied to the twist-sabonius blade. This wind turbine attached to safety lamp on the road is produced to use electricity generated through the wind tunnel experiment. In this paper results, this wind turbine system is expected to produce the power source installed the heat ray and safety lamps on the road.