• 한국정보전자통신기술학회논문지
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• 제12권3호
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• pp.265-272
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• 2019

본 연구에서는 예금은행 주택담보대출에 대해 매년 문제가 야기되는 지속적인 증가율을 정성적으로 파악하고, 다시 안정세를 보일 수 있는 특성요인을 파악하고자 향후 주택담보대출에 대해 정량적으로 분석하고 증가율 추세에 대한 대책을 마련하고자 예측 연구를 실행하였다. 빅-데이터 분석에 많이 쓰이는 R 프로그램을 활용하여 데이터를 분석한 결과 ARIMA 모형의 모수를 (0,1,1)(0,1,1)[12]로 추정하였을 때, MAPE와 RMSE의 검정 결과 기준으로 가장 최적의 ARIMA 모형인 것으로 나타났다. 해당 모수를 통해 향후 5년 (60개월간)의 추정치를 예측한 결과, 평균 4.5%대의 증가율을 나타냈다. 그러나 이는 사회 환경요인의 요인을 반영하지 않은 예측 값이기 때문에 다양한 사회 환경요인을 활용하여 외부 충격요인에 대한 구조적 모형 연구가 이루어져야 할 것이며, 추후 관련연구들은 이와 같은 한계들을 극복하여 진행될 필요가 있으며 정책적인 활용도를 높이기 위해 많은 실증연구가 이루어져야 하겠다.

• Journal of Welding and Joining
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• 제5권3호
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• pp.53-61
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• 1987

Post weld heat treatment(PWHT) is usually carried out to remove the residual stress and to improve the microstructure and mechanical properties of welded joints. By the way, welding structure transformed owing to PWHT and reheating for repair loads the random cycles fatigue as offshore welding structure of constant low cycle fatigue as pressure vessel, and then, pre-existing flaws or cracks exist in a structural component and those cracks grow under cyclic loading. Therefore, the effects of PWHT and stress ratio on fatigue crack growth behaviors were studied on the three regions such as HAZ, sub-critical HAZ and deposit metal of welded joints in SM53 steel. Fatigue crack growth behavior of as-weld depended on microstructure and fatigue crack growth rate of HAZ was the lowest at eac region, but after PWHT it was somewhat higher than that of as-wel. In case of applying the stress($10kg/mm^2$) during PWHT, fatigue crack growth resistance tended to increase in the overall range of .DELTA.K.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.185.2-185.2
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• 2015

Tin Oxide (SnO2) has been widely investigated as a transparent conducting oxide (TCO) and can be used in optoelectronic devices such as solar cell and flat-panel displays. In addition, it would be applicable to fabricating the wide bandgap semiconductor because of its bandgap of 3.6 eV. There have been concentrated on the improvement of optical properties, such as conductivity and transparency, by doping Indium Oxide and Gallium Oxide. Recently, with development of fabrication techniques, high-qulaity SnO2 epitaxial thin films have been studied and received much attention to produce the electronic devices such as sensor and light-emitting diode. In this study, powder sputtering method was employed to deposit epitaxial thin films on sapphire (0001) substrates. A commercial SnO2 powder was sputtered. The samples were prepared with varying the growth parameters such as gas environment and film thickness. Then, the samples were characterized by using XRD, SEM, AFM, and Raman spectroscopy measurements. The details of physical properties of epitaxial SnO2 thin films will be presented.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1995년도 제2회 KOSCI Workshop
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• pp.91-103
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• 1995

In recent years, significant advances have been made in the development of methods to predict ash behavior in utility boilers. This paper provides an overview of methods used to assess and predict ash formation and deposition. It has discussed some of the key problems associated with the formation and deposition of ash during the combustion of pulverized coal. Although considerable progress has been made in understanding of the fundamental mechanisms of ash formation, transport, growth, and strength development, there is still much work to be done. There is a need to develop quantitative relationships between the characteristics of the entrained ash and the physical properties of ash deposits that influence deposit growth, strength development, and cleanability. Also data from bench-scale, pilot-scale, and full-scale units are needed in order to determine operating conditions which will minimize deposition problems, maximize efficiency, and reduce emissions.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.289-289
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• 2011

The conducting polymer thin films were deposited using the gas phase method which known as molecular layer deposition (MLD). Terephthalaldehyde (TPA) and p-phenylenediamine (PD) were used as monomers to deposit conducting polymer. Self-terminating nature of TPA and PD reaction were demonstrated by growth rate saturation versus precursors dosing time. Infrared spectroscopic and X-ray photoelectron spectroscopy were employed to determine the chemical composition and state of conducting polymer thin films. Layer by layer growth and polymerization of thin films can be showed by shifting of absorption edge using UV-VIS spectroscopy. This conducting polymer fabricated by using MLD method gives the opportunity to develop new hybrid materials by combining inorganic materials in nanoscale.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.305-305
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• 2012

The organic-inorganic hybrid polymer thin films were deposited using the gas phase method which known as molecular layer deposition (MLD). Titaniumchloride (TiCl4) and 1,4-phenylenediamine (PD) were used as monomers to deposit hybrid polymer. Self-terminating nature of TiCl4 and PD reaction were demonstrated by growth rate saturation versus precursors dosing time. Infrared spectroscopic and X-ray photoelectron spectroscopy were employed to determine the chemical composition and state of hybrid polymer thin films. Layer by layer growth was showed by increasing UV-VIS absorption peak of hybrid polymer thin films.

• 한국세라믹학회지
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• 제33권1호
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• pp.25-34
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• 1996

Yttria stabilized zirconia (YSZ) thin films were prepared by the electrochemical vapor deposition (EVD) method on the porous Al2O3 substrates which were fabricated by different substrate thickness and porosity. Film growth rates decreased with increase on the substrate thickness and porosity and obeyed a parabolic rate law. Activa-tion energy calculated from the parabolic rate onstants was 69.9 kcal/mol. With increase on the deposition time, monoclinic phase was appeared and then disappeared. YSZ penetrated deeply into substrates when the EVD temperature decreased. Electrical conductivity of the films was 0.09 S/cm at 100$0^{\circ}C$ similar to the value of YSZ single crystal.

• 한국표면공학회지
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• 제36권2호
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• pp.141-147
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• 2003

Silicon carbide thin film was deposited in APCVD and LPCVD system with 1,3-DSB precursor 1,3-DSB is the single precursor to deposit SiC on Si at low temperature. SiC film was deposited at $850^{\circ}C$ lower than ordinary temperature ($1000~1200^{\circ}C$) in CVD process. SiC thin film glowed to high oriented (111) plane in APCVD system. In LPCVD system, SiC film groved to preferred (220) plane at same temperature. This discrepancy between preferred planes can be described by the difference of deposition mechanism. Amorphous phase and crystal defect were observed in APCVD system with the main growth mechanism of mass transport limited region. But in LPCVD system, we got the SIC film of uniform, faceted structure and high quality.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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• pp.1-20
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• 1998

Processing of thin films by chemical vapor deposition (CVD) is accompanied by chemical reactions, in which the rigorous kinetic analysis is difficult to achieve. In these conditions, thermodynamic calculation leads to better understanding of the CVD process and helps to optimise the experimental parameters to obtain a desired product. A CVD phase diagram has been used as guide lines for the process. By determining the effect of each process variable on the driving force for deposition, the thermodynamic limit for the substrate temperature that diamond can deposit is calculated in the C-H system by assuming that the limit is defined by the CVD diamond phase diagram. The addition of iso-supersaturation ratio lines to the CVD phase diagram in the Si-Cl-H system provides additional information about the effects of CVD process variables.

• 문화기술의 융합
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• 제5권4호
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• pp.277-282
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• 2019

본 연구는 저축은행의 재무건전성에 미치는 결정요인들을 분석하였다. 특히 구조조정 이후 예대율이 재무건전성과 어떠한 상관관계를 가지는지 실증분석 하였다. 2014년 저축은행 구조조정이 마무리되면서 자산운용에 변화가 있었으며, 최근 또 다시 재무건전성을 우려하고 있는 상황에서 저축은행 재무건전성에 미치는 재무특성 변수에 대한 분석이 요구되는 시점이다. 분석결과를 요악하면, 저축은행의 예대율과 고정이하여신비율 간의 관계는 1% 유의수준에서 음(-)의 값을 가지는 것으로 나타났다. 즉 예대율이 높을수록 고정이하여신비율이 감소하는 것으로 나타났다. 예대율이 높다는 것은 대출재원으로 예금이외의 시장성 수신 등을 이용할 가능성이 높다는 것이다. 이는 저축은행의 입장에서 공격적인 대출포트폴리오를 구축하는 것이 쉽지 않을 가능성이 존재한 결과라고 할 수 있다. 즉 저축은행이 예수금을 통한 대출재원 조달이 어려울수록 위험회피성향이 강하게 나타날 수 있음을 시사하고 있다. 그 외 기업대출비중, 평균이자비용, 경제성장률이 높을수록 위험지표가 높게 나타났으며, 자산규모가 크고, 대출증가율이 높을수록 위험지표가 낮게 나타났다. 예대율 증가는 위험추구행위가 감소될 수 있으나 저축은행 재무건전성에 무조건 긍정적으로 작용함을 의미하는 것은 아니다. 따라서 예대율 규제를 통해 특정대출의 과도한 자산확대 유인을 감소하고, 대출 포트폴리오 관리를 통해 선제적 건전성 관리가 이루어져야 할 것이다.