• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.480-484
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• 2006

We propose a new PDP cell structure named DIDE (Dual Ignition Discharge Electrodes) structure with a long electrode gap to realize a high luminous efficacy. Suggested DIDE structure basically has a long electrode gap $(200{\mu}m{\sim}400{\mu}m)$, nevertheless, because of auxiliary electrodes formed on the front panel, can be driven at relatively low voltage. The discharge characteristic of DIDE structure was much different from that of conventional structure, which was analyzed by IR emission images using IICCD (Image Intensified Charge Coupled Device). The study can explain some particular characteristics of DIDE structure. As a result, the long electrode gap and low voltage effect can be expected in DIDE structure, and a very high luminous efficacy of 7.5 lm/W has been achieved in monochrome green test panel adopting the new cell structure with Ne-Xe (12%) mixture at 400 torr.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.10
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• pp.3381-3386
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• 1996

The engine performance and combustion characteristics of methanol blended fuel in spark ignition engine were discussed on the basis of experimental investigation. The effects of methanol blending fuel on combustion in cylinder were investigated under various conditions of engine cycle and blending ratio. The results showed that the engine performance was influenced by the methanol blending ratio and the variations of operating conditions of test engine. The increase of fuel temperature brought on the improvement of combustion characteristics such as cylinder pressure, the rate of pressure rise and heat release in an engine. The burning rate of fuel-air mixture, the exhaust emissions and the other characteristics of performance were discussed also.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.3
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• pp.154-159
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• 2016

Recently it has been focused that the automobile engine has developed in a strong upward tendency for the use of the high viscosity and poorer quality fuels in achieving the high performance, fuel economy, and emission reduction. Therefore it is not easy to solve the problems between low specific fuel consumption, and exhaust emission control at automotive engine In this study, it is designed and used the test bed which is installed with fuel injector controller. In addition to equipped engine using CRDI by controlling the injection timing with modulator, it has tested and analyzed the engine cycle variation characteristics, as it is varied that they are the operating parameters: fuel injected quantity, injection timing, engine speed and scavenging pressure.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.1-9
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• 1978

Biological safety, physico-chemical and microbiological experiments were carried out in order to study the possibility of radiation sterilization on medical products, such as polyethylene and polystyrene bottles, gauze sponges and surgical silk suture. Results are as follows: 1. Biological test on plastic samples as to acute systemic toxicity, eye irritation, skin irritation, pyrogen, haemolysis showed satisfactory results. But physico-chemically, the oxidizable matter, nonvolatile residues, residue on ignition seemed to be increased slightly in irradiated samples, though the experimental results were within the range of U.S.P. 19, N.F. and K.P. III. 2. After irradiation, both plastic and gauze sponges showed considerable decrease in pH. 3. Most medical products were sterilized by 1.5 Mard. For the sterilization of the suigical silk suture, 4.5 Mrad is required dul to its radiation resistant micro-organisms. 4. Biologically, total dose of 2.5 Mrad was safe enough to sterilize the medical products, and physico-chemically the results are acceptable according to U.S.P. 19 and K.P. III. However, better results may be expected when the quality of material and additives are improved.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.228-233
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• 1999

In this paper we develop an electronic starter circuit that is suitable for Neon sign operation of switch-start fluorescent lamps. The developed starter enable single pulse ignition of fluorescent lamp at the peak point of preheating current, irrespective of the position of the Tum-On signal. This is possible due to the sequential operation of two transistors different in their operation characteristics and a diode operation characteristic. The switching endurance test using this starter has been carried for more than 3000 hours for a single switch-start on a severe blinking condition of preheating of 0.1s and of successive lighting interval of 0.1s.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.1 s.24
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• pp.13-23
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• 2006

A propellant mainly consisting of nitric ester including nitrocellulose and nitroglycerine is characteristic of being decomposed naturally. And this phenomenon is known as being affected mostly by its storing temperature and humidity. In this research, the effect of storing temperature and humidity on self life has been studied by measuring the contained quantity of residual stabilizer of propellant KM30Al, which are parts of 155MM propelling charge K676 and K677; the method for the measurement is acceleration aging test, and decomposition reaction equation, Eyring Equation and Berthlot Equation were used for the calculation. As result of this study, it was found that the storing temperature influenced seven times as large as the storing humidity upon the self life of the propellant KM30Al, Furthermore, especially in the high temperature region, the storing temperature had a dominant effect on the self life.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1579-1583
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• 2008

We proposed the new structure of ac plasma display panel(PDP) to improve the luminous efficacy and driving voltage characteristics. Through two-dimensional numerical simulations, we analyzed the effects of new counter discharge type, which consists of counter sustain electrodes and auxiliary electrodes. Generally, an advantage of AC PDP with the counter sustain electrodes has been known for the driving characteristics of the low voltage. In this work, the new counter structure using the ignition discharge by the auxiliary pulse applied to the address electrode showed the result of the increased luminous efficacy. The short gap discharge between two auxiliary electrodes on the front plate could intensity the long gap discharge between counter electrodes. The reliability of simulation result could be confirmed by the experimental result in the test panel.

• Economic and Environmental Geology
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• v.32 no.2
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• pp.151-159
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• 1999

This research was carried out to evaluate the possible usage of natural clay materials collected from the Kimpo landfill site and nearby clay mines as a clay liner material. In order to evaluate the possible usage as a clay liner material, specific gravity, pH, loss-on-ignition, organic carbon content and mineralogical composition of clay materials were measured. The Atterberg limit test and the size analysis were performed for the engineering classification and the prediction of hydraulic conductivity of clay materials. Caution exchange capacity and batch tests were also carried out for the assessment of attenuation capacity. Clay specimens of KPNCL, KP-1, KP-2 and SH were recommended as suitable clay linder materials from viewpoint of their basic quality and attenuation capacity.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.1
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• pp.19-27
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• 2005

The spray characteristics of DISI injector has a great role in engine efficiency and emission. Thus, many researchers have been studied to investigate the spray characteristics of hollow cone type and slit type injector which are used in DISI engine. In this study, we tried to provide spray parameters which effect on the spray characteristics such as injection pressure, ambient pressure and ambient temperature. In addition, we calculated $t_b\;and\;t_c$ to investigate the break up mechanism of test injectors and also obtained $C_v$ to evaluate the spray characteristics. From this study, As the ambient pressure increases in case of slit injector, $C_v$ decreases.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.2
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• pp.149-153
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• 2003

Besides the fuel spray behavior and combustion chamber shape. an air motion has a key role on exhaust gas emission and performance in a DI diesel engine. A swirl ratio represents the ratio of the intake swirl velocity to the engine speed. The main purpose in this work is to investigate the effects of the swirl ratio to the combustion characteristics. A shroud valve machined to change the swirl ratio. Test was carry out by changing the engine speed, nozzle diameter and swirl ratio in a single cylinder diesel engine. From this study, the optimized combustion was found at swirl ratio 2.7. And it was also found that the increasing the maximum cylinder pressure with an increasing swirl ratio lead to decrease a smoke and to increase NOx.