• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.63-67
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• 1991

Amorphous silicon films were deposited on glass, [100] single crystal silicon wafer with thermally grown silicon dioxide, and [100] silicon wafer substrates by Plasma Enhanced Chemical Vapor Deposition(with argon diluted silane source gas). Growth rate, UV optical band edge, and the hydrogen quantity in the amorphous silicon films have been investigated as a function of the preparation conditions by measuring film thickness, UV-absorbency, and FT-IR transmittance. The growth rate of the ${\alpha}$-Si:H films increases with increasing substrate temperture, flow rate and R.F. power density. The UV optical band edge shifts to blue with the increases in the deposition pressure. Increasing substrate temperature shifts the UV optical band edge of the films to red. Hydrogen quantity in the ${\alpha}$-Si:H films increases with an increases in the R.F. powr and decreases with an increase in the substrate temperature.

• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.108-112
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• 2000

The electric charge generated by flowing insulation liquid can create hazardous spark in transfer line and receiving tank etc. These electrification has generally been measured by current measurement with a ammeter connected to the receiving tank. This paper reports on the experimental result obtained by this method. As a experimental results: The injected charge value for unit volume increased in the following condition, the edge of the needle electrode was sharp, the number of needle electrode was fewer, the edge of the needle electrode was located close to the inside wall. When the charge density in the charge reducer is constant, electrode current and electrode potential by the charge injection from outside increase with increasing of oil velocity and streaming current. The electrode potential in charge reducer is made maximum value at edge point of reducer inside and minimum value at center line of charge reducer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.52-57
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• 1995

An accurate and efficient single-integral semi-numerical model is developed and applied to analyse effects of localized electronic states in the mobility gap on the drain-current versus gale-voltage characteristics of hydrogenated amorphous field-effect transistors. It is shown that the low-density deep-gap states distributed in the midgap also sensitively and largely influence the device electronic performance as well as well as the large-density tail states distributed near the conduction band edge.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.1
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• pp.210-216
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• 2014

The edge in the image is a part which the brightness changes rapidly between the object and the object or objects and background, and includes information of the features such as size, position, orientation, and texture of the object. The edge detection is the technique that acquires these information of the images, and now the researches to detect edges are making steady progress. Typical conventional edge detection methods are Sobel, Prewitt, Roberts using the first derivative operator and Laplacian method using the second derivative operator and so on. These methods is more or less insufficient that the characteristics of the edge detection in the image added salt and pepper noise. therefore, in this paper, an edge detection algorithm using modified mask that applies different size mask according to noise density of local mask is proposed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.4 s.74
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• pp.399-406
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• 2006

The natural frequencies of Al square plates with a brass inclusion were analyzed by the rule of mixtures. The rule of mixtures is the method to derive natural frequency mutiplying effective inplane wane speed and nondimensional frequency parameters. Numerical models were Al square plates with an inclusion with cantilever type, 2 clamped edge-2 free edge type, 3 clamped edge-1 free edge type and fully clamped edge type. In cantilever type plates, 2 clamped edge-2 free edge type plates and 3 clamped edge-1 free edge plates with an inclusion, good agreement within 10% obtained from rule of mixtures' results and numerical analysis results within inclusion area ratio 1/9. It was found that the natural frequencies of the cantilever type, 2 clamped edge-2 free edge type and 3 clamped edge-1 free edge type plates with an inclusion decrease as the size of inclusion increases when inclusion is located center of plates. And when the density of inclusion is less than the plates, natural frequency of plates with an inclusion increases as the size of inclusion increases.

• Journal of the Korean Society of Combustion
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• v.18 no.1
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• pp.13-20
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• 2013

Leading edge statistics are obtained by direct numerical simulation(DNS) of freely propagating incompressible and stagnating compressible turbulent premixed flames. Conditional averages of velocities in terms of reaction progress variable, c, and local flame surface density, ${\sum}^{\prime}_f$, are defined and compared through the flame brush. It holds asymptotically that $<u>_f=<S_d>_f$ and $<u>_u-<u>_b=D_t/L_w$ with the characteristic length scale of $\bar{c}$ variation, $L_w$. It also holds that $<u>_b=<u>_f$ for a freely propagating flame under no mean strain rate. The turbulent burning velocity, $S_T$, is determined by the conditional statistics at the leading edge under large activation energy.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.10
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• pp.1244-1251
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• 1988

Edge is one of the primitive features of an image and is widely used in image classification and analysis. New edge extration methods using central moments are presented and show various characteristics according to the order of moment, definition of both random variables and probability density functions. The proposed methods use the integral of differences between local mean and pixels in the window whereas most of conventional edge operators use only differential concepts. This gives good noise immunity and extracts fine edges.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.180.2-180.2
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• 2014

Opening a bandgap by forming graphene nanoribbons (GNRs) and tailoring their properties via doping is a promising direction to achieve graphene-based advanced electronic devices. Applying a first-principles computational approach combining density functional theory (DFT) and DFT-based non-equilibrium Green's function (NEGF) calculation, we herein study the structural, electronic, and charge transport properties of boron-nitrogen binary edge doped GNRs and show that it can achieve novel doping effects that are absent for the single B or N doping. For the armchair GNRs, we find that the B-N edge co-doping almost perfectly recovers the conductance of pristine GNRs. For the zigzag GNRs, it is found to support spatially and energetically spin-polarized currents in the absence of magnetic electrodes or external gate fields: The spin-up (spin-down) currents along the B-N undoped edge and in the valence (conduction) band edge region. This may lead to a novel scheme of graphene band engineering and benefit the design of graphene-based spintronic devices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.109-110
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• 2007

Plasma etching process에서 magnetic field 영향에 관한 연구이다. High level dry etch process를 위해서는 high density plasma(HDP)가 요구된다. HDP를 위해서 MERIE(Magnetical enhancement reactive ion etcher) type의 설비가 사용되며 process chamber side에 4개의 magnetic coil을 사용한다. 이런 magnetic factor가 특히 wafer edge부문에 plasma charging에 의한 damage를 유발시키고 이로 인해 device Vth(Threshold voltage)가 shift 되면서 제품의 program 동작 문제의 원인이 되는 것을 발견하였다. 이번 연구에서 magnetic field와 관련된 plasma charge damage를 확인하고 damage free한 공정조건을 확보하게 되었다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.560-566
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• 1997

Dislocation behavior in the ZnSe crystal grown by seeded vapor transport was investigated. Etch pit shape with the ZnSe plane and dislocation arrangement were shown. Also the variation of the dislocation density in the crystal was disclosed. The dislocation density along the lateral growth direction was not changed but the dislocation density along the vertical growth direction was reduced as the crystal grew. The average dislocation density of the grown crystal was $4{\times}10^4 /\textrm{cm}^2$.