• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2015.11a
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• pp.157-158
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• 2015

본 논문에서는 광원 노출도를 이용한 저조도 영상 시인성 개선 기법을 제안한다. 제안 기법은 저조도 영상의 저주파 성분과 고주파 성분을 각각 개선한 뒤 병합하여 시인성이 개선된 영상을 얻는다. 먼저, 영상에서 추출한 광원 노출도를 기반으로 저주파 성분을 저조도 영역과 고조도 영역으로 구분하고, 각 영역의 특징을 반영한 전달 함수의 독립적인 생성 및 적용을 통해 개선된 저주파 성분을 얻는다. 다음으로 저주파 성분의 개선 결과로부터 저주파 성분의 개선 정도와 텍스처 정도를 얻고, 이들 값을 이용하여 고주파 성분을 효과적으로 개선한다. 실험을 통하여 제안 기법이 기존 기법에 비하여 우수한 시인성 개선 결과를 보임을 확인한다.

• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.197-201
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• 1996

To greatly decrease bolting rate and deterioration of root quality, seeds of Angelica gigas had sown and grown several month earlier than traditional seedtime. Roots were harvested in the middle of November in same year. Roots were devided to several parts such a fune root, secondary root, stele and cortex of main root. We ditermined and compared with the major constisuents contained in each parts of 1 and 2 year old roots. Among each parts of root, the amount of constituents in the fine root and cortex were much higher than those in stele of main root. Content of decursin and decursinol angelate was higher 6.5% in 2 year old root than 4.8% in 1 year old root and their component ratio showed 10:7.5 in 1 year old root and 10:6.0 in 2 year old root, respectively. But merits as a material of oriental medicine for 1 year old root that cultivated by early short-time growing seedling were generally acknowledged.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.205-209
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• 1999

Chinese foxglove(Rehmannia glutinosa) is receiving much attention as one of the principal medicinal crops and the crud drug. This study was conducted to obtain the basic breeding information of Chinese foxglove derived from tissue culture. To compare plant characteristics between local variety and tissue cultured seedlings, plant growth and root yield has been investigated. In addition, catalpol and free sugar contents were also analized. The ability for the storage of root stock originated from tissue culture seedlings were better than that of local variety. The growth and root yield of in vitro propagated plants were superior to those of conventionally propagated plants. Root yield of 1-year-old and 2-year-old seedlings investigated 112% and 246% respectively than Seacheon local shows 384 kg/10 a. Although there were no significant different between tissue culture seedlings and conventionally propagated one, slight decline of component contents in tissue culture plants were still existed. Investigated sugar content among Seocheon local, 1-year-old tissue culture seedlings, and 2-year-old tissue culture seedlings were 1.86%, 1.21%, and 1.10% respectively. Catalpol content as one of standard materials indicates 0.46% in Seocheon local and 0.40% in tissue cultured ones.

• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.565-570
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• 2017

Tobacco smoke emitted during smoking is divided into a main-stream and side-stream smoke. Most of the tobacco smoke that spreads to a room while smoking is a side-stream one. The side-stream tobacco smoke is two to three times more harmful than that of the main-stream tobacco smoke. In this study, the removal efficiency of CO, $H_2S$, $NH_3$ and HCHO in a side-stream tobacco smoke using the doping component of $TiO_2$ photocatalysts was confirmed. As a result, CO was removed up to 78.37%, which indicated that the $TiO_2$ photocatalytic process is effective for CO removal. Also, the removal efficiencies of CO, $H_2S$ and HCHO were greatly affected by the amount of doped O and Si components of the $TiO_2$ photocatalyst. In conclusion, the more doped O and Si components had, the higher removal efficiencies of harmful substances were achieved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1642-1647
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• 2009

Changes in aerosol characteristics during 2006 ${\sim}$2008 Asian dust events in Cheoan were investigated by measuring mass, ion and elemental concentrations of fine and coarse particles. The average mass concentrations of daily TSP, PM10, PM2.5 were 214.9, 160.3, and 95.9${\mu}\;g/m^3$during Asian dust events, which were 3.08, 2.58, and 1.95 times higher than Non-asian dust events. The maximum concentrations of TSP, PM10, and PM2.5 were 850.1, 534.4, and 233.3${\mu}\;g/m^3$, which were 12.19, 8.60, and 4.76 times higher, respectively. Increases in ion concentrations were not significant during Asian dust events, but elemental concentrations including soil components such as Fe, Al, Ti increased by 17.1 and 43.4 times for fine and coarse particles, respectively. The results clearly indicate that metallic components from soil constituents were the major components in Asian dusts sampled at Cheonan.

• Conservation Science in Museum
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• v.17
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• pp.17-42
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• 2016

A scientific analysis was performed on the gold belt with eight dangling ornaments discovered in the large Silla period Seobongchong Tomb. The object's gold sheets, nails, curved ornaments and gold wire were analyzed separately. Results show that all the components are gold-silver alloy, each varying in overall alloy composition. Gold sheets of two different gold contents are used for the belt, 17-18K gold and 19-20K gold, this seemingly by design. Nails are 20K gold, while the curved ornaments and gold wire of the belt are mostly 18K gold. Gold sheets for the dangling ornaments are mainly of 17-19K gold. Connecting rings used in the dangling ornaments are 17-19K gold, nails 17-20K gold and the curved ornaments and wire 19K gold.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.4
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• pp.341-347
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• 2001

Harmonics and fundamental reactive current of nonlinear loads in serious unbalanced power condition, are compensated by current synchronous detection(CSD) theory which is also acceptable for single phase power system. But, the CSD theory is not suitable any more, in case of controlled independently harmonics and reactive component. Therefore, a new algorithm, the expanded current synchronous detection(ECSD) theory for a three phase active power filter based on decomposition of fundamental reactive, distorted components, is proposed in this paper. The proposed ECSD theory is experimented and tested comparison with a few power theories under asymmetrical condition in power system.

• Journal of Food Hygiene and Safety
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• v.2 no.3
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• pp.89-95
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• 1987

This studies was performed to investigate the quality control of Pueraria RadiI tea. Experimental subjects were 8 kinds of tea and wet and dry Pueraria RadiI which were collected from the Seoul area. For standards, Daidzein and Daidzin were isolated from Pueraria Radix. Analysis method was carried out by HPLC using ${\mu}-Bondapark{\;}C_{18}$ column and UV 254 nm detector. Samples were extracted with methanol by Cold method (at room temperature for 24 hours) and Hot extraction method (at $^{\circ}C$ for 4 hours) Pueraria radix contained 0.08% Daidzein and 0.66% Daidzin Most of the Pueraria Radix tea contained extract of Pueraria Radix less than the labled amounts listed.

• Journal of the Korean Geophysical Society
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• v.6 no.1
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• pp.25-29
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• 2003

We suggest a method that vectorially composes 3-component earthquake records in the frequency domain, to reduce the uncertainties in the analysis of the Fourier amplitude spectrum. The use of the Fourier amplitude spectrum composed from 3 components has two advantages. First, it provides a more accurate estimate of seismic moment by eliminating the vector-partition term that appears in individual component. Second, it provides more accurate estimates of seismic moment, corner frequency, high-frequency decay constant($χ$) .etc., by enhancing the shape of the Fourier amplitude spectrum. The latter is especially useful in the analysis of small earthquakes with low signal-to-noise ratios.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.762-765
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• 2010

특정 시간에 동시 연주된 다수 음원의 onset 을 검출하기 위해서는 음원 분리 문제가 선결되어야 한다. 특히, 드럼과 같은 조음(?音) 악기 신호 검출 문제를 해결하기 위해서는 음원 분리 방법의 성능이 중요하다. 이에 본 연구에서는 효과적인 음원 분리 방법으로 알려진 확률적 은닉 성분 분석(PLCA) 방법에 기반한 주요 악기 신호의 onset 검출 방법을 제안한다. 효과적인 onset 검출을 위해, 첫째, 확률적 은닉 성분 분석으로 훈련 된 비음수 주파수 성분 중 최적의 성분을 선택하는 방법을 적용하고, 둘째, 드럼 악기 신호의 정확한 onset 검출을 위해 고안된 비음수 시계열 신호 threshold 방법을 적용한다. 실험에서는 제시된 방법을 이용하여 드럼의 주요 악기 신호 onset 검출 성능이 향상됨을 보인다.