• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.2
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• pp.124-127
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• 2004

W/n-GaN Schottky diodes were irradiated with $^{60}Co\;{\gamma}-rays$ to doses up to 315Mrad. The barrier height obtained from current-voltage (I-V) measurements showed minimal change from its estimated initial value of ${\sim}0.4eV$ over this dose range, though both forward and reverse I-V characteristics show evidence of defect center introduction at doses as low as 150 Mrad. Post irradiation annealing at $500^{\circ}C$ increased the reverse leakage current, suggesting migration and complexing of defects. The W/GaN interface is stable to high dose of ${\gamma}-rays$, but Au/Ti overlayers employed for reducing contact sheet resistance suffer from adhesion problems at the highest doses.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.207-208
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• 2006

Intrusion detection technology is highlighted in order to establish a safe information-oriented environment. Intrusion detection system can be categorized into anomaly detection and misuse detection according to intrusion detection pattern. In this paper, we propose an architecture to make up for the defect of conventional anomaly intrusion detection. This architecture reduces additional resource consumption and cost by placing the agent in the strategic location in Internet.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.69-70
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• 2006

Air-guided single-mode propagation of THz radiation in a photonic crystal waveguide (PCW) has been experimentally demonstrated for the first time. The PCW has been fabricated by introducing an air defect at the center of an air/Si 1D photonic crystal. By using a THz time-domain spectroscopic technique, we have experimentally shown that the guiding mechanism of the air-guiding PCW is the photonic bandgap effect.

• Journal of Power Electronics
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• v.3 no.1
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• pp.40-48
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• 2003

In this paper, a hybrid power system with photovoltaic/wind/diesel generators is proposed to solve the defect of stand-alone type power system in a remote area. A hybrid power system has a power-balanced controller to equilibrate generation power with a given load demand and which is composed of common DC power system. To execute a power-balanced control, a hybrid power system is assumed that all of power generators have the characteristics of an equivalent current-source and load sharing control technique must be needed at the same time. So this paper discusses the structure of power-balance control for hybrid power system. And through the results of simulation, the proposed scheme was verified.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.460-462
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• 2003

One of many elements considered important is TR-Cost in restructed electrical power market. KEMA supposed the TR-Cost system which involved an allocation rate of groups of generator and load as 5 to 5 but it isn't based on electrical and economic theory. Also there is a defect that we cann't calculate each allocation to numerous members forming the group of generators and loads. Therefore, in this paper, we propose an allocation method by using "generator forcused TR MLF" & "load forcused TR MLF" in consideration of economic signal.

• Journal of Surface Science and Engineering
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• v.49 no.2
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• pp.172-177
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• 2016

In this paper, various electrochemical experiments were conducted in seawater solution to evaluate corrosion damage behavior of arc thermal sprayed Inconel 625 coating on SS400 steel in marine environment. As a result, corrosion damages of thermal sprayed Inconel 625 coating preferentially occurred at the defect area, and they were observed as a form of pitting corrosion in the galvanostatic experiments. In Tafel analysis, corrosion current density of Inconel 625 coating was relatively high due to influence of interconnected pores and Cr oxides in the thermal spray coating layer. On the other hand, the result of the potential measurement, thermal sprayed Inconel 625 coating should need the post-treatment which can compensate the defects like pores and cracks because Inconel 625 coating presented a higher potential of about 290 mV than that of the SS400 steel.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.69-70
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• 2007

Now the IEC flicker measuring algorithms and its flicker index of $P_{st}$ and $P_{lt}$ are accepted internationally as standards. But it is recently found that IEC flickermeter has a main drawback that it cannot afford to detect the fluctuating patterns of voltage envelope caused by interharmonics higher than 102Hz in the 60Hz power system. This is brought about by two components of IEC flicker measuring steps, squaring and low-pass filtering. This paper presents the innate defect of IEC flickermeter and proposes a modified measuring method considering the voltage flickers by subharmonics and interharmonics.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.22-29
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• 2008

This paper provides the evaluation method for the pressure vessel with internal wall-thinning defect, which is based on ASME design criteria. Pressure vessel has wall-thinning partially and patch reinforcement has been attached for reliable operating. However, present partial wall thinning could be through wall thinning at the next inspection time with present corrosion progress speed. Therefore safety margin was calculated for various conditions from present wall-thinning condition to additive patch reinforced condition via two-dimensional and three-dimensional, geometrically linear FE analyses using elastic materials.

• Annual Conference of KIPS
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• 2014.11a
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• pp.1014-1017
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• 2014

모바일 카메라 모듈의 성능 향상에 따라, 카메라 렌즈의 미세한 오염도 큰 불량요인으로 작용하게 되었다. 그로인한 새로운 검사 시스템들과 검사방법이 제안되었다. 본 논문에서 제안하는 새로운 검사방식은 영상처리를 통해 기존에 비해 정확도가 높고, 전처리 횟수가 적은 이점이 있어 산업현장에서 적용 시 효율성 증대를 기대할 수 있다.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.257-262
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• 2009

Image processing has been utilized for assessment of infrastructure surface coating conditions for years. However, there is no robust method to overcome the non-uniform illumination problem to date. Therefore, this paper aims to deal with non-uniform illumination problems for bridge coating assessment and to achieve automated rust intensity recognition. This paper starts with selection of the best color configuration for non-uniformly illuminated rust image segmentation. The adaptive-network-based fuzzy inference system (ANFIS) is adopted as the framework to develop the new model, the box-and-ellipse-based neuro-fuzzy approach (BENFA). Finally, the performance of BENFA is compared to the Fuzzy C-Means (FCM) method, which is often used in image recognition, to show the advantage and robustness of BENFA.