• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.11
• /
• pp.690-695
• /
• 2014

In this paper, we develop a explosion-proof LED lighting (Ex circuit) circuit of Explosion-proof LED Signal Lamp (Ex LSL) to utilize the core module of the explosion-proof Local Control System (Ex LCS) for offshore plant applications. And then analyzed its electrical, optical and thermal characteristics. Ex circuit was applied input voltage from AC/DC(12~254) V. In this experiments, stable light-on characteristics were confirmed by eyes for the every input voltages with min. 78,462 and max. $517,975cd/m^2$ of luminance. also Output current and output luminance was made proportional. Because the measured maximum surface temperature of Ex circuit was $54.23^{\circ}C$ at AC 48 V, Ex circuit was rated with T6 of temperature class. Finally, Ex circuit was shown stable light on characteristics under the $-50^{\circ}C$ and $60^{\circ}C$ during 12 hours of test period.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.10
• /
• pp.771-777
• /
• 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 Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.1
• /
• pp.74-81
• /
• 1998

It is not good joint that today's traffic control system that the course of traffic volume increase tendency is followed, in the traffic volume is approched into the time of my car. Accordingly when we analyzed the existing traffic signal control system, the traffic signal system is developed from the machine type that the motor was centered, to get up to date, to the intelligence electron signal control system. But yet, when we have a test and a A/S on the control circuit, the circuit that is designed to the center IC and ROM are complicated. Also, the time of pass lamp that the car line stream is going, can not extended automatically a time till the traffic volume is decreased to the same direction. This theme must be a real time intelligence control system that the time of pass lamp can extend aumatically. The circuit of sequence ladder diagram on the traffic signal control of a crossroads that is desinged, can be satisfied the complicated vehicle order. Therefore when the circuit is changed, the new developed system is economical with that dosen't needs any of components to require the circuit equipment, and the time is saved with needlessness of the circuit wiring again, and have a much trustworthy. The control method of pass signal lamp in the car line stream connecting among PLC and Relay and Temp Sensor, can be changed to hand operation and to semi-automation and to all-automation. New intelligence traffic signal system is composed with all-together system of T Sensor + Video Camera + IBM PC that is able to guiding the establishment of traffic order.

• Proceedings of KOSOMES biannual meeting
• /
• 2003.05a
• /
• pp.117-123
• /
• 2003

It is impossible to apply present standards and test methods because the radiation principle and mechanism of a new marine lantern using light emitting diodes is different from those of the existing marine lantern which uses an incandescent electric lamp. Thus. in this study, we discuss the research and development on the light emitting diodes marine lantern and specifications.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.20 no.6
• /
• pp.132-139
• /
• 2012

It is generally needed to test durability and lifetime when we develop parts in new technology. In this paper, the accelerated degradation analysis methods are developed to test them. This study is presented robust model estimation method that is less affected by outlier in regresstion model estimation. In addition, the lifetime can be predicted by Degradation-stress relationship in stress level.

• Proceedings of the Korean Society of Marine Engineers Conference
• /
• 2000.11a
• /
• pp.143-151
• /
• 2000

Dissolved silica is make some critical trouble at steam turbine. And, we must measure it to ppb level. We were looking for the best measuring method of the silica. Via this study, we could found it in the N-IR spectroscopy technology. This dissertation have been discuss about system structure, system fundamentals and performance test. At the test, we were study in the spectral interference of $NH_3$. We know that existing system had some problem. It is structural frailties of single beam type. Therefore we were study for double beam type structure. And we obtain a good result. In the result, it have been discuss that conduct a test of $NH_3$ effect.

• Publications of The Korean Astronomical Society
• /
• v.28 no.3
• /
• pp.75-82
• /
• 2013

An optical grism for education is fabricated and tested. It is composed of a transmission grating as dispersion element and a prism as diffraction angle compensation device. The transmission grating is Edmundoptics #49-584(spatial frequency 600 lines/mm, dimension $50mm{\times}50mm$). The prism is the fused silica type with angles ($41.3^{\circ}$, $-48.7^{\circ}$, $-90^{\circ}$). The grism device is fabricated by bonding the transmission grating and the prism with an optical adhesive. The zig for assembling the grism, telescope and camera is composed of an aluminum tube, an aluminum disk ring and a T-ring camera adaptor. The fabricated optical grism spectrograph is tested in laboratory using Halogen lamp and Neon lamp with DSLR camera. And the grism assembled with reflector telescope is tested in a field using stellar light. The results show good agreements with design parameters. The wavelength coverage range of the grism is 250 nm at the un-deviated wavelength of 506 nm. The wavelength resolution is 0.11 nm/pixel.

• Korean Journal of Artificial Intelligence
• /
• v.4 no.1
• /
• pp.4-7
• /
• 2016

These days, citizens have made change of food life to take Western style food and to suffer from diabetes because of excessive nutrition taking, less exercise, stress and other environmental factors. They may suffer from diabetes because of genetic defect, surgery of pancreas, disinfection and medicine and others. One of ten Koreans may have symptom of diabetes to be popular. The diabetes that is a kind of metabolic disease has high blood sugar at disorder of hyper insulinism and/or defect of insulin action. Long time high blood sugar may produce chronic disease of kidney, eyes, nerve, heart and blood vessel and others. The purpose of health care of diabetes patient was to reach target blood sugar by diet, physical exercise and medicine and to prevent and delay complication. Diabetes patient shall control blood sugar to keep healthy. The blood sugar control requires time and effort, and all of the patients are difficult to make effort and to spend time. You can control blood sugar by the application. The application allows patients to control blood sugar and to save time and efforts and to make small sized input and automation of remaining area. The service was limited to blood sugar graph, and user carries smart phone to conduct test and to have difficulty. Further study needs to solve the problems and to investigate blood sugar testing not carrying smart phone and to make application of easy control of blood sugar.

• Current Photovoltaic Research
• /
• v.5 no.3
• /
• pp.83-88
• /
• 2017

The growth of intermetallic compounds is an important factor in the reliability of solar cells. Especially, the temperature change in the soldering process greatly affects the thickness of the intermetallic compound layer. In this study, we investigated the intermetallic compound growth by Sn-diffusion in solder joints of solar cells. The thickness of the intermetallic compound layer was analyzed by IR lamp power and hot plate temperature control, and the correlation between the intermetallic compound layer and the adhesive strength was confirmed by a $90^{\circ}$ peel test. In order to investigate the growth of the intermetallic compound layer during isothermal aging, the growth of the intermetallic compound layer was analyzed at $85^{\circ}C$ and 85% for 500 h. In addition, the activation energy of Sn was calculated. The diffusion coefficient of the intermetallic compound layer was simulated and compared with experimental results to predict the long-term reliability.

• Journal of the Korean Vacuum Society
• /
• v.13 no.2
• /
• pp.47-53
• /
• 2004

A getter pump test system is being developed as a core item of the national project for establishing the foundation of the vacuum technology in our country. A preliminary test system was prepared for developing the getter test procedure, and providing design requirements and system specifications before setting up the getter pump test system. The pumping speed and the pumping capacity of getter elements of low activation temperature used in the seal-off vacuum devices, for the hydrogen, carbon monoxide and nitrogen gases, were measured using the preliminary test system. The pumping characteristics of a domestic getter, developed mainly for the gas purifier, were compared with those of a foreign getter used widely in the lamp factories.