• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.572-573
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• 2005

Discharge of the flat lamp lighting source research are requested very much. For improving brightness. life time. efficiency of flat lamp and plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. When a distance of discharge electrode is 5.5mm and width is 16.5mm. we measured electron temperature and electron density measured with single Langmuir probe in flat lamp. We tested the discharge from 100 Torr to 300 Torr pressure. The pulse type was rectangular with frequency 20kHz and duty ratio was 20%. In result. electron temperature decreases and electron density increased as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.566-567
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• 2005

Until now variable pattern classification methods have been introduced. So, variable methods in PD source classification were applied. NN(neural network) the most used scheme as a PD(partial discharge) source classification. But in recent year another method were developed. These methods is present superior to NN in the field of image and signal process function of classification. In this paper, it is show classification result in PD source using three methods; that is, BP(back-propagation), ANFIS(adaptive neuro-fuzzy inference system), PCA-LDA(principle component analysis-linear discriminant analysis).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.6
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• pp.457-461
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• 2009

In this paper, barrier height between Ni-silicide and source/drain is reduced utilizing Pd stacked structure (Pd/Ni/TiN) for high performance PMOSFET. It is shown that the barrier height is decreased by Pd incorporation and is dependent on the Pd thickness. Therefore, Ni-silicide using the Pd stacked structure is promising for high performance nano-cale PMOSFET.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.10
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• pp.653-656
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• 2014

$Cs_3Sb$ photocathode was formed by newly developed process and successive in-situ lighting devices were fabricated in a process chamber. R, G, and B phosphors were applied on the anode plate, respectively. Major parameters such as brightness, power consumption, and efficacy were measured. The wavelength of LED excitation source was 450 nm. Both high power and low power modes were applied in the measurement. Measurement values were clearly differentiated by the voltage application modes. The measured values of each parameter was good enough to be applied for general lighting source. The results showed that $Cs_3Sb$ photocathode formed in atmospheric conditions was functioning as good as the photocathode formed in UHV conditions, and thus it could be applied to advanced lighting devices.

• Journal of the Korean Ceramic Society
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• v.47 no.3
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• pp.262-267
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• 2010

a-SiC has been thought as an ideal candidate for conventional silicon at many applications. However, the uniformity problem of deposition has been a obstacle for conventional use of a-SiC:H films. a-SiC:H films were deposited on (100) silicon wafer by RPECVD system in various temperature. HMDS and $H_2$ gas were used as a precursor and a carrier gas, respectively. The flow rate of HMDS source and $C_2H_2$ dilution gas was fixed in order to study the carbon effect on the film stoichiometric and bonding properties. The plasma power varied from 200 to 400W. We used three types of source delivery line to control the uniformity and film properties of deposited film. We showed that the change of source delivery line has effect on the film uniformity of deposited film and this change of line did not affect on film properties. Also, the change of deposition conditions has effect on the film uniformity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.1
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• pp.16-20
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• 2021

In this study, we tried finding new materials to improve the stain resistance properties of polymer insulating materials. Using the filtered vacuum arc source (FVAS) with a graphite target source, DLC thin films were deposited on silicon and polymer insulator substrates depending on their thickness to confirm the surface properties, physical properties, and structural properties of the thin films. Subsequently, the possibility of using a DLC thin film as a protective coating material for polymer insulators was confirmed. DLC thin films manufactured in accordance with the thickness of various thin films exhibited a very smooth and uniform surface. As the thin film thickness increased, the surface roughness value decreased and the contact angle value increased. In addition, the elastic modulus and hardness of the DLC thin film slightly increased, and the maximum values of elastic modulus and hardness were 214.5 GPa and 19.8 GPa, respectively. In addition, the DLC thin film showed a very low leakage current value, thereby exhibiting electrical insulation properties.

• Design & Manufacturing
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• v.15 no.4
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• pp.32-36
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• 2021

In this study, the cause of the decrease in transmittance of the outer lens among the causes of the decrease in the amount of light in the automobile headlamp was identified, and the improvement method was selected to determine the effect. The causes of defects that lower the transmittance of the outer lens are divided into a moisture problem and a haze problem. The moisture problem is caused by the temperature difference between the inside and the outside of the head lamp, and the haze problem occurs when the heat inside the head lamp evaporates the haze component contained in the plastic material and attaches it to the outer lens. In order to improve the haze problem that occurs in plastic raw materials, the structures of the bulb light source type headlamp and the LED chip light source type headlamp were analyzed. Among them, the housing material of the LED chip light source type headlamp, which is structurally prone to haze gas, was selected as the test target. In the mass-production injection process of the housing, the drying process was selected as a method to minimize haze gas without adding a separate production process. After extracting a sample every drying time at a constant drying temperature, the sample was put into a haze tester and the residual amount of haze gas was measured. As a result, it was confirmed that the residual amount of Haze gas in the material decreased as the drying time increased.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1347-1354
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• 2020

To improve the efficiency of MC criticality calculation, an acceleration method of fission source convergence which gives an improved initial fission source is proposed. In this method, the MC global homogenization is carried out to obtain the macroscopic cross section of each material mesh, and then the nonlinear iterative solution of the SP3 equations is used to determine the fission source distribution. The calculated fission source is very close to the real fission source, which describes its space and energy distribution. This method is an automatic computation process and is tested by the C5G7 benchmark, the results show that this acceleration method is helpful to reduce the inactive cycles and overall running time.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.658_659
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• 2009

This paper deals with the numerical implementation of the material sensitivity analysis, which is used to efficiently determine an optimal electric current distribution on a ship hull by corrosion of ship. A material sensitivity formula for the forward problem formulated in terms of the equivalent current method is analytically derived. Then, the components of the adjoint system including the electric pseudo-source are thoroughly investigated in order to obtain the first-order gradient information of an objective function with respect to the electric current. The purposed method has been successfully applied to a model ship and the predicted result on the underwater electric field due to corrosion of ship have been compared to that computed by FNREMUS software.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.10
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• pp.911-915
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• 2008

EL (electro-luminescent) device as a light source has an advantage in embodying large area with great flexibility. On nickel foil as an electrode and backplane, we demonstrated a white EL flexible light source with blue phosphor layer combined with color change layer. A correlation between color change layer and color coordination was analyzed by Gaussian method, and then the color coordinate was controlled near to (0.33, 0.33) of pure white light.