• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3230-3232
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• 2000

DR (Digital Radiography) system will be the best candidate for next generation x-ray diagnosis system. DR system will replace x-ray film by computer monitor and provide various merits like reduced processing time, easy recording, remote diagnosis and etc. In this paper, we propose the pre-processing algorithm which is designed to compensate dead and defected pixel for x-ray detector panel. We also designed DSP(Digital Signal Processor) based DR image processing board for real-time processing of suggested algorithm.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2110-2112
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• 2000

This paper describes the self healing characteristics of a metalized polypropylene film(MPPF) used for energy storage capacitors. In the experiment, a d.c. voltage was applied to the MPPF, and the partial discharge inception voltages(PDIVs), the applied voltages at self healing, the burn out area and the current in the grounding conductor were measured and recorded. As a result, it was found that no PDs were found till the first pre-self healing occurred, and the applied voltage at self healing was increased with PPF thickness. Self healing was much more dependant on the shape of the air void than its diameter and the burn out area and the current in the grounding conductor at self healing was also increased with the applied voltage at self healing.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.1
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• pp.28-38
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• 2009

Numerical simulation is performed for microdroplet deposition on a pre-patterned micro-structure. The liquid-air interface is tracked by a level-set method, which is improved by incorporating a sharp-interface modeling technique for accurately enforcing the matching conditions at the liquid-gas interface and the no-slip condition at the fluid-solid interface. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to improve the patterning accuracy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.120-123
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• 2000

This paper reports a newly developed sol-gel process to synthesize dense YBCO thick films with $BaTiO_3$ additives using electrophoretic deposition and metal alkoxide sol/particle suspension, which we successfully produce dense $YBCO+BaTiO_3$ ceramics at a rather low temperature, compared with the sintering temperature used in conventional methods. The thick films of HTS were prepared by electrophoretic deposition, using pre-sintered powder with barium titanate addition in the form of $BaTi(OR)_6$ solution in suspension for electrophoresis. The conditions for applied voltage and deposition times for electrophoretic deposition of HTS thick films were studied in detail.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.136-137
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• 2007

Wear resistant TiAlN thin film has been widely deposited on the surface of cutting and forming tools by using Arc Ion Plating. TiAlN films are deposited by the processes designed by the Taguchi L18 experimental design. The L18 experimental design is applied to achieve surface properties and adhesion. The deposition parameters are working pressure, substrate temperature, bias voltage, arc power and pre-sputtering bias voltage and time. The most influential parameters on surface properties and adhesion are substrate bias voltage, working nitrogen pressure and arc power. The optimal coating processes are obtained for surface properties and adhesion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.169-172
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• 2005

공정시 플라스틱 기판의 변형을 방지하기 위해 PC(Polycarbonate) 기판을 약 12시간 동안 pre-annealing시킨 다음 SiN(silicon nitride)와 PI(Poly-imide)를 각각 Sputter와 Spin-Coater를 이용하여 Coating하였다. 완성된 PC 기판위에 Themal Evaporation으로 Calsium을 증착한 뒤 Al을 올렸다. Calsium 증착 된면에 삼성 코닝의 글래스를 UV resin으로 부착 시킨 다음 상온에서 투습률을 측정하였다. 측정 간격은 12시간으로 하였으며 Calsium Test 의 정확도 향상을 위해 CCD Camera로 측정하여 컴퓨터로 분석하였다. 그래픽 저장 파일은 저장시 이미지 손실을 방지하기 위해 Bitmap방식을 그대로 사용 하였으며 정확도 향상을 위한 분석 프로그램은 MicroSoft 사의 Visual C++로 작성하였다. 화상 처리 면적은 컴퓨터 시스템의 처리 속도를 감안하여 70*70 으로 하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.371-371
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• 2010

탄소나노튜브(CNT)는 기계적인 특성이 뛰어나며, 화학적으로 안정하고, 전기적으로 도체 및 반도체성을 가지고 있을 뿐만이 아니라 직경이 최소 1nm 수준으로 종횡비 및 비표면적이 매우 큰 특성을 가지고 있다. CNT는 투명전극, 유연성 디스플레이, 전자종이 분야 등 투명 전극 응용 분야에서 ITO 대체 신소재로 각광을 받고 있다. 본 발표에서는 SWCNT 전도막의 특성을 향상시키기 위해 PET 기판에 다양한 전처리 방법을 적용하여 SWCNT의 부착력 및 접착력, 투명전극의 면저항, 투과도 및 균일도 향상을 통해 SWCNT 투명전극 특성향상 연구를 진행했다. 접촉각과 표면에너지 제어를 통한 박막특성과의 상관관계 분석, 전처리 방법에 따른 표면에너지 및 제타포텐셜 변화와 박막특성과의 관계를 규명, Roughness 조절을 통한 기판의 면저항과 투과도 향상, 플라즈마 및 polymer 처리를 통해 물리적, 화학적 기판 전처리에 따른 SWCNT 투명전극 특성 향상을 목적으로 실험을 진행했다. 플라즈마 처리 후 polymer 처리된 박막에서는 친,소수 작용기 양의 변화에 따른 상관관계를 보이지 않았지만, 플리즈마 처리 후 친,소수 작용기 양과 Roughness 변화정도에 대해서는 면저항과 투과도의 변화를 보였다.

• Journal of Surface Science and Engineering
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• v.53 no.6
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• pp.343-350
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• 2020

The degradation of mechanical properties of nitride coatings to steel substrates is one of the main challenges for industrial applications. In this study, plasma nitriding treatment was used in order to increase the mechanical properties of Mo-Cu-N coating to the H13 tool steel. The nanostructured Mo-Cu-N coating was deposited using pulsed DC magnetron sputtering method with a single alloy Mo-Cu target. Mechanical properties of MoN-Cu coated samples after nitriding were found to be relatively better than non-nitrided MoN-Cu coating.

• Journal of the Korean Society of Radiology
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• v.8 no.4
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• pp.171-180
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• 2014

In this study, the authors attempted to measure the skin dose by irradiating the actual dose on to the TLD(Thermo-Luminescence Dosimeter) and EBT3 Film used as the In-vivo dosimetry after planning the same treatment as the actual patient on a Phantom, because the erythema or dermatitis is frequently occurred on the patients' skin at the time of the proton therapy of medulloblastoma patient receiving the proton therapy. They intended to know whether there is the usefulness for the dosimetry of skin by the comparative analysis of the measured dose values with the treatment planned skin dose. The CT scan from the Brain to the Pelvis was done by placing a phantom on the CSI(Cranio-spinal irradiation) Set-up position of Medulloblastoma, and the treatment Isocenter point was aligned by using DIPS(Digital Image Positioning System) in the treatment room after planning a proton therapy. The treatment Isocenter point of 5 areas that the proton beam was entered into them, and Markers of 2 areas shown in the Phantom during CT scans, that is, in all 7 points, TLD and EBT3 Film pre-calibrated are alternatively attached, and the proton beam that the treatment was planned, was irradiated by 10 times, respectively. As a result of the comparative analysis of the average value calculated from the result values obtained by the repeated measurement of 10 times with the Skin Dose measured in the treatment planning system, the measured dose values of 6 points, except for one point that the accurate measurement was lacked due to the measurement position with a difficulty showed the distribution of the absolute dose value ${\pm}2%$ in both TLD and EBT Film. In conclusion, in this study, the clinical usefulness of the TLD and EBT3 Film for the Enterance skin dose measurement in the first proton therapy in Korea was confirmed.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.57-70
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• 2014

The study proposes an exploratory analysis on the success of animation films in Korea industry. It identifies animation films that have been successful in the Korean film industry during 2004-2013 period and explores (1) how the number of screens allocated to the films have been changed; (2) what are the major factors that influence the success of the films; (3) what are the differences between Japan and the US animation in terms of plots and genres; and (4) how the characteristics of the US animations are related to the success of the US market, the global market, and Korean market. Analyses show that the number of screens allocated to the animation films has been consistently increased due to the vertical integration of Korean film industry; and the (FTA) period, months in year (summer and winter break months for middle and high school students), and the number of screens allocated to the films were the major factors influencing the financial success of animations. It also finds that specific characteristics embedded in its own cultural trait were shown in the plots and genres in the animations. Lastly the study also finds that specific set of characteristics extracted from IMDB site influence certain markets. Budgets and actor's power were found to influence the success in the US market while period (pre-FTA, FTA, post-FTA) only influence the success in Korean market. The study points out that the success of the US and Japan animations in Korean film industry are due to the historicity of animation cultures which are not found in Korean animation industry.