• 한국멀티미디어학회논문지
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• 제11권2호
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• pp.153-162
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• 2008

본 논문은 밴드 매칭과 경계제거 두 부분으로 나누어진 새로운 인페인팅 방법을 제안한다. 밴드 매칭은 삭제하고자하는 영역(인페인팅 영역)을 둘러싸는 밴드와 영상의 나머지 영역을 비교하여 그 차이가 가장 작은 영역을 인페인팅 영역에 채워 넣는 것이고, 경계제거는 밴드매칭으로 채워진 영역과 주변영역 사이에 나타나는 경계를 제거하는 것이다. 제안하는 방법은 인페인팅 영역으로 연속된 선이 지나는 경우 좋지 못한 결과를 얻는 경우가 있는데, 이러한 경우 영역분할이라는 과정을 더한다. 영역분할 방법은 인페인팅 영역을 작게 나누고, 분할된 각각의 영역에 대해 밴드 매칭과 경계제거를 수행하는 것이다. 영역분할을 이용하는 경우 분할 개수에 따라 여러 개의 다른 결과를 얻을 수 있고, 사용자는 그 결과들 중에서 가장 좋은 결과를 선택할 수 있다.

• 한국환경과학회지
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• 제19권5호
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• pp.577-584
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• 2010

The generation of $TiO_2$ nanoparticles by a thermal decomposition of titanium tetraisopropoxide (TTIP) was carried out experimentally using a tubular electric furnace at various synthesis temperatures (700, 900, 1100 and $1300^{\circ}C$) and precursor heating temperatures (80, 95 and $110^{\circ}C$). Effects of degree of crystallinity, surface area and anatase mass fraction of those $TiO_2$ nanoparticles on photocatalytic properties such as decomposition of methylene blue was investigated. Results show that the primary particle diameter obtained from thermal decomposition of TTIP was considerably smaller than the commercial photocatalyst (Degussa, P25). Also, those specific surface areas were more than 134.4 $m^2$/g. Resultant $TiO_2$ nanoparticles showed improved photocatalytic activity compared with Deggusa P25. This is contributed to the higher degree of crystallinity, surface area and anatase mass fraction of $TiO_2$ nanoparticles compared with P25.

• Archives of Metallurgy and Materials
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• 제64권2호
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• pp.607-611
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• 2019

Thermal/cold spray deposition were used for additive manufacture of oxide dispersion strengthened (ODS) steel layers. Mechanically alloyed F/M ODS steel powders (Fe(bal.)-10Cr-1Mo-0.25Ti-0.35Y2O3 in wt.%) were sprayed by a high velocity oxygen fuel (HVOF) and cold spray methods. HVOF, as a thermal method, was used for manufacturing a 1 mm-thick ODS steel layer with a ~95% density. The source to objective distance (SOD) and feeding rate were controlled to achieve sound manufacturing. Y₂Ti₂O₇ nano-particles were preserved in the HVOF sprayed layer; however, unexpected Cr₂O₃ phases were frequently observed at the boundary area of the powders. A cold spray was used for manufacturing the Cr₂O₃-free layer and showed great feasibility. The density and yield of the cold spray were roughly 80% and 45%, respectively. The softening of ODS powders before the cold spray was conducted using a tube furnace of up to 1200℃. Microstructural characteristics of the cold sprayed layer were investigated by electron back-scattered diffraction (EBSD), the uniformity of deformation amount inside powders was observed.

• 자원환경지질
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• 제55권5호
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• pp.477-495
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• 2022

본 연구는 충주 앙성지역 탄산천의 이용량에 따른 수위 및 수질 변화 패턴을 분석하여 탄산천의 지 속가능성을 검토하였으며, 암석/물의 ⁸⁷Sr/⁸⁶Sr 값과 주변 W-Mo 광상에서의 함-CO₂ 유체포유물의 산출, 주변의 지질학적 특성 등을 고려하여 탄산 성분의 기원과 공급에 대하여 고찰하였다. 1986년부터 2017년까지의 자료에 의하면, 탄산천의 수위 심도는 탄산 온천공 개발 초기(1986~1992년)에 비해 후기(2009~2015년)에 매우 하강되어 있으며, 적정양수량도 점차 감소되는 경향을 보였다. 탄산 성분 역시 개발 초기에 비해 후기로 가면서 지속적으로 저감되었으나, 2012년 이후로는 안정된 양상을 보였다. CO₂ 성분의 기원과 공급은 연구지역 주변에 발달된 W-Mo 석영맥 광상(0.5×1.5×수 km 규모)의 지질학적 생성 환경과 크게 관계된 것으로 추정되며, CO₂ 성분의 공급이 지하 심부의 마그마 활동으로부터 무한히 공급되는 것이 아니라 과거 지질시대에 형성된 부존지역에서 공급되기 때문에 탄산천의 지속가능성 유지를 위해서는 연구지역 내 탄산수의 이용량을 효율적으로 조정할 필요가 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권2호
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• pp.61-75
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• 2022

This study evaluated the potential threat of agricultural and human activities to groundwater in the Noseong stream watershed, a typical agricultural area, through hydrogeochemical characteristics and microbial community analyses. The groundwater in the study area was Ca-SO₄ and Ca-HCO₃ types alluvial aquifer mainly used for agricultural and living purposes, and contained high levels of NO₃^- and Cl^- ions generated from anthropogenic sources such as fertilizer, livestock wastewater, and domestic sewage. Proteobacteria was most abundant in all samples with an average of 46.1% while Actinobacteria, Bacteroidetes, and Cyanobacteria were dominant on an occasional basis. The prevalence of aerobic bacteria such as the genus Mycobacterium, Flavobacterium, and Sphingomonas suggests that groundwater was well connected with the surface layer. The potential pathogen Mycobacterium was detected in most samples, and other pathogenic bacteria were also widely distributed, indicating the vulnerability to contamination. Therefore, an integrated management system is required to secure the sustainable use of groundwater in agricultural areas with high groundwater dependence.

• 한국재료학회지
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• 제16권2호
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• pp.116-122
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• 2006

The effects of milling time in argon and hydrogen atmospheres on the hydrogen sorption speed of a getter alloy, $Zr_{57}V_{36}Fe_{7}$, was studied. The hydrogen sorption speed of milled alloys was evaluated at room temperature. In argon, as the oxygen content increased with milling time, the hydrogen sorption speed decreased accordingly. In hydrogen, on the other hand, the oxygen content decreased at first with milling time but started increasing after 5 hrs of milling time. Similar to the case of argon, however, the hydrogen sorption speed changed exactly in the opposite direction with the oxygen content, exhibiting the maximum rate at 5 hrs. These results suggest that in both atmospheres the hydrogen sorption speeds are inversely related with the oxygen contents.

• 한국식품영양학회지
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• 제32권6호
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• pp.669-677
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• 2019

The impact of storage temperature on the changes in acid value(AV), peroxide value(POV), color value, total phenolic content(TPC), and antioxidant activity in perilla seed(PS) was investigated. The PS was stored at 25, 35, and 45℃ for four weeks. An increase in the storage temperature resulted in significantly increased AV, POV, redness, and yellowness of the PS. Conversely, TPC, antioxidant activity, and redness of the PS significantly decreased. The changes in the AV and POV followed a first-order kinetic model, and the kinetic parameters such as k, t_1/2, Q₁₀ and Ea were calculated. The k and t_1/2 values decreased with increasing storage temperature and the Q₁₀ values for the AV and POV were 1.56, 1.91, 4.61, and 3.43, respectively. The Ea for the changes in of the AV and POV in the PS were 70.40, 102.63 kJ/mol, respectively. The half-life values for the AV and POV of the PS at 25℃ were 169.52 and 373.18 days, respectively, while the values at 45℃ for those, were 28.47 and 27.93 days, respectively.

• Nuclear Engineering and Technology
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• 제55권10호
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• pp.3617-3627
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• 2023

This study presents a method to solidify spent ion-exchange resin (IER) in a metakaolin-based geopolymer and shows results of mechanical strength, immersion, leaching, irradiation, and thermal cycling tests for waste acceptance criteria (WAC) to repository. The geopolymer waste form with 20 wt% of simulated spent IER met the WAC in South Korea (ROK), and the leaching tests of various sized-waste forms up to 15.0 × 30.0 cm and waste loadings up to 20 wt% for 1-5 d and 1-90 d achieved a leachability index, L_i > 6. In a leaching test for 5 d, the cumulative fraction leached (CFL) for Cs, which leached the most, was linearly correlated with the square root of leaching time for all waste forms, and L_i increased as the size of the waste form increased. The CFL was also correlated with elapsed time in the 90 d leaching test. The correlations among CFL, time, and volume-to-surface area ratio of waste forms used to estimate the L_i of Cs of a 200-L sized geopolymer with 15 wt% IER showed the L_i values as 14.73 (5 d) and 17.71 (90 d), respectively, indicating that the large-sized geopolymer waste form met the WAC.

• Current Photovoltaic Research
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• 제1권2호
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• pp.90-96
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• 2013

We report here flexible dye-sensitized solar cells (DSSC) based on Ti-mesh electrodes that show good mechanical flexibility and electrical conductivity. $TiO_2$ nanotube arrays prepared by electrochemical anodizing Ti-mesh substrate were used as photoanode. A Pt-coated Ti-mesh substrate was used as counter electrode. The photoanodes were modified by coating a $TiO_2$ porous layer onto the $TiO_2$ nanotubes in order to increase the specific surface area. To increase the long term stability of the DSSCs, a gel type electrolyte was used instead of a conventional liquid type electrolyte. The DSSC based on $33.2{\mu}m$ long porous $TiO_2$ nanotubes exhibited a better energy conversion efficiency of ~2.33%, which was higher than that of the DSSCs based on non-porous $TiO_2$ nanotubes.

• 생물환경조절학회지
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• 제32권4호
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• pp.257-266
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• 2023

본 연구는 밀폐형 식물생산 시스템(CPPS)에서 광도와 CO₂ 농도에 따른 오이와 토마토 묘의 생육을 조사하기 위해 수행되었다. 오이(Cucumis sativus L. 'Joeunbaekdadagi')와 토마토(Solanum lycopersicum L. 'Dotaerang Dia')를 50구 트레이에 파종하여 CPPS에서 25℃, 50% 상대습도에서 4일 동안 발아시켰다. 발아 후 CO₂ 농도 처리 및 광도는 각각500(무처리구), 1,000, 그리고 1,500µmol·mol^-1 와 100, 200, 그리고 300µmol·m^-2·s^-1로 재배하였다. 오이의 엽면적은 광도보다 CO₂ 농도 변화에 영향을 받으며 1,500µmol·mol^-1 CO₂ 농도 조건에서 엽면적이 가장 넓었다. 반면에 토마토의 엽면적은 CO₂ 농도와 광도 변화에 따른 유의미한 차이를 나타내지 않았다. 광도가 증가함에 따라, 오이와 토마토의 생육과 묘소질(충실도와 엽면적비)이 유의적으로 증가하는 경향을 나타냈고, 광도 300µmol·m^-2·s^-1에서 가장 높았다. 오이와 토마토 묘의 근권 표면적, 근단 수는 광도의 증가에 따라 유의적으로 증가하였다. 결론적으로 CO₂ 농도와 광도의 조절은 오이와 토마토 묘의 생육과 묘소질을 조절할 수 있으나, CO₂ 농도보다 광도의 영향을 크게 받았으며, 광도가 증가함에 따라 생육, 묘소질, 그리고 뿌리가 발달하는 경향이 나타났다.