• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.214-220
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• 2019

Hwangryunhaedok-tang (HT) is prescribed in oriental medicine to treat inflammation-related diseases. This study examined the anti-bacterial effect to select the index components of Traditional Chinese Medicine (TCM) HT. The disc diffusion method and minimum inhibition concentrations (MIC) tests were conducted to measure the antibacterial activity of HT. The strains were Staphylococcus aureus ATCC 25923 and Escherichia coli 23724. Berberine and geniposide were selected as the index components of HT and were analyzed quantitatively by high-performance liquid chromatography (HPLC). As a result, the inhibition ring was formed at $11.7{\pm}1.3mm$ and $8.7{\pm}0.7mm$ at HT 20 mg and 10 mg on S.aureus ATCC 25923, respectively; and $8.0{\pm}0.0mm$ at HT 20 mg on E.coli ATCC 23724. The MIC were 31.25 mg/mL in S.aureus ATCC 25923 and 125.0 mg/mL in E.coli ATCC 23724. In quantitative analysis for standardization, HT contained 16.55 mg/g of berberine and 81.85 mg/g of geniposide. Overall, when antibiotics are developed using natural products, they may reduce the side effects and inhibit resistant bacteria. If research on HT continuously proceeds, positive developments are expected to be made in oriental medicine as well as in various other industries.

• Korean Journal of Optics and Photonics
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• v.9 no.4
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• pp.245-250
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• 1998

A new computational algorithm is presented for the peak point detection of white light interferograms. Assuming the visibility function of white light interferograms as a quadratic polynomial, the peak point is searched so as to minimize the error sum between the measured intensity data and the analytical intensity. As compared with other existing algorithms, this new algorithm requires less computation since the peak point is simply determined with a single step matrix multiplication. In addition, a good robustness is obtained against external random disturbances on measured intensities since the algorithm is based upon least squares principles.

• The KIPS Transactions:PartB
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• v.8B no.1
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• pp.59-65
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• 2001

워터쉐드 변환은 영상분할을 위한 강력한 도굴로 이용되고 있으나, 일반적으로 다수의 국부적 최소점들로 인한 과분할 현상을 초래하여 이를 해결하기 위한 많은 방법들이 연구되어지고 있다. 본 논문에서는 동시정보행렬을 분석하여 비 관련 최소점들을 억제함과 동시에 의미 있는 화소 집합들만을 마커로 선택하고 레이블링하는 자동마커 추출단계와 각 마커로부터 범랑과정 및 재 레이블링에 의한 워터쉐드 추출단계를 수행하여 영상을 분할하는 자동마커 기반 워터쉐드 영상분할 알고리즘을 제안한다. 제안한 알고리즘이 과분할 정도로 현격히 줄이는 것을 보이기 위해 일반영상과 텍스쳐 특성이 강한 ICQ(Indo Cyanine Green) 망막영상에 적용하여 실험 분석하였다.

• Research in Plant Disease
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• v.30 no.2
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• pp.199-205
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• 2024

Erwinia amylovora, a causal pathogen of fire blight, has been continuously inducing damage to the apple and pear trees in South Korea since 2015. Farmers apply antibiotics during blooming season to prevent the fire blight. However, continuous use of antibiotics can induce the emergence of resistant bacteria, which consequently reduces control efficacy. In this study, we assessed the minimal inhibitory concentration (MIC) of streptomycin, using a total of 361 E. amylovora isolates that were collected from the six provinces of South Korea from 2019 to 2023. As a result, the MIC of streptomycin ranged from 0.5 to 4 ㎍/ml and the strA-strB genes were not identified from the isolates. The MIC was higher in the isolates from Gyeonggi-do, Gangwondo, and Chungcheongbuk-do compared to those from other three provinces. These results may bring broad attention to the use of streptomycin and aid in developing a management protocol for the occurrence of fire blight in South Korea.

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.2
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• pp.121-140
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• 1999

The various oriental herbal medicines, which have usually been used for treatment of reducing fever, purging intense heat and detoxication, were screened to determine the antibacterial activity and the minimal inhibitory concentration against pulmonary disease-causing Klebsiella pneumoniae, Streptococcus pyogenes, and Streptococcus pneumoniae. The results obtained were as follows: 1. Among the 23 oriental medicines tested, the water-soluble extracts of Coptis japonica, Scutellaria baicalensis and Picrorrhiza kurrooa showed the antibacterial activity against K.pneumoniae and that of C. japonica against S. pyogenes. The antibacterial activities of C. japonica, Prunusmume, Schizandra chinesis, Scutellaria baicalensis were also found against S.pneumoniae. When C.japonica was used, the high antibacterial activity was shown against Bacillus subtilis and other extracts showed a little activity against B. subtilis and E. coli as a control. 2. The ethanol-soluble extracts of Patrinia scabriosaefolia, P. mume, S. baicalensis, S. chinesis showed the antibacterial activity against K. pneumoniae and those of S. baicalensis, C. japonica, S. chinesis, P. mume agaist S. pyogenes and S. pnuemoniae. However, those extract showed a little antibacterial activity against B. subtilis and E. coli except for that the extract of C. japonica showed comparatively high growth inhibition of B. subtilis. 3. Among the medicinal herbs tested, the water and ethanol extrats of C. japonica showed very extcellent antibacterial activity against the pathogenic bacteria and controls. 4. When the water-soluble extracts of C. japonica and S. baicalensis, minimal inhibitory concentrations (MICs) against K. pneumoniae were $10mg/m{\ell}$ and $22 mg/m{\ell}$, respectively. The MICs of the ethanol-soluble extracts of P. mume and P. scabriosaefolia were $5mg/m{\ell}$ and $20mg/m{\ell}$, respectively. 5. For the MICs against S.pyogenes, C. japonica showed $15mg/m{\ell}$ with the water-soluble extract and P. mume and C. japonica with the ethanol-souble extract did $5mg/m{\ell}$ and $10mg/m{\ell}$, respectively. 6. For the MICs against S. pneumoniae, C. japonica and P. mume with the water- and ethanol-souble extract showed $5mg/m{\ell}$ and $10mg/m{\ell}$, respectively. As a result, the highest antibacterial activity was found in the water- and ethanol-soluble extracts of C. japonica against pulmonary disease-causing bacteria, K. pneumoniae, S. pyogenes. and S. pnuemoniae. Also, the water- and ethanol-soluble extracts of S.chinesis. P.mume, S.baicalensis, and P.kurrooa showed hight antibacterial activities.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.613-616
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• 1993

현재 가공시스템은 생산성 향상을 위해 다방면에 걸쳐 자동화가 시도되고 있고, 한 걸음 더 나아가서 무인화가 추구되고 있다. 이런 상황에서 자동화와 무인화의 효과를 극대화하기 위해 가공공정의 고속화, 즉 주축시스템과 이송시스템의 고속화서 활발히 진행되고 있다. 고속가공의 특징으로는 비절삭 시간의 절약과 절삭시간의 단축을 들 수 있는데 , 구조적으로도 큰 영향을 미쳐서 작은 절삭력의 발생으로 인해 구조물이 고강성화에서 저강성화로 변화되고 있다. 본 연구에서는 고속주축 Housing의 열전달 경로를 관찰하고 열변 위의 양상을 파악해서 전. 후부 베어링의 열발생량 차이에서 오는 주축심의 각변위 억제대책을 제시하고, 주축 Housing의 조립용 기준 핀을 Housing의 Z축방향 열변위가 최소가 되도록 위치를 결정하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1914-1915
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• 2011

본 논문은 천정형 크레인의 파라미터 추정과 Fuzzy LMI 제어기법을 이용한 흔들림 억제 제어를 제안한다. 실제 크레인을 제어함에 있어서 크레인의 동적모델링 이외에도 미지의 물리적 매개변수 값을 규정하는 것은 중요한 요소이다. 이러한 점을 고려하여 크레인의 물리적 매개변수를 최소자승추정 방법을 통해 추정하여 크레인 제어의 성능향상을 제공한다. 또한 Fuzzy LMI 제어기법을 적용하여 천정형 크레인의 이동 중 발생하는 흔들림을 제어한다.

• Analytical Science and Technology
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• v.7 no.3
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• pp.403-411
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• 1994

To isolate, purity and identify of bioactive compounds involved in alfalfa allelopathy and/or autotoxicity, experiment was conducted. Isolation and separation procedures used from an 80% methanol extract of fresh alfalfa leaves(1kg), silica gel thin layer chromatography(TLC), followed by Droplet Counter Current Chromatography(DCCC). Preliminary identification was examined by high preformance lipid chromatography(HPLC). Four phenolic compound, salicylic acid, scopoletin, rutin, and quercetin, were identified and identified all compounds were phytotoxic to alfalfa seed germination and seedling growth. Among these compounds, quercetin treatment($10^{-3}M$) was most inhibitory to alfalfa seed germination and seedling growth. These compounds may be, at least in part, involved autotoxicity and allelopathy.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.604-605
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• 2010

산업이 고도화 됨에 따라 박막 코팅에 대한 수요가 점차 증가하고 있으며 이에 따라 플라즈마를 이용한 마그네트론 스퍼터 시스템에 대한 수요 역시 증가하고 있다. 코팅 공정에서 가장 문제가 되는 것은 고압의 플라즈마 발생장치를 사용함으로써 야기되는 아크현상이라 할 수 있다. 따라서, 플라즈마 전원 장치의 핵심 기능 중의 하나는 아크 차단 성능이라 할 수 있으며 가능한 한 최소의 아크 에너지를 유지할 필요가 있다. 아크를 억제하는 방법은 최단 기간 내에 아크를 검지하여 출력을 차단함으로써 아크 발생에 필요한 에너지의 유입을 감소시키는 방법이 사용되고 있다. 본 연구에서는 아크를 검지하는 기존의 방식을 살펴보고 최단기간에 아크를 검지할 수 있는 새로운 형태의 검지 방식을 제안한다.

• Korean Journal of Optics and Photonics
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• v.8 no.6
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• pp.506-509
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• 1997

A novel narrowband wavelength bandpass filter with a large side-lobe suppression was proposed in vertical coupler structure using coupling variation in propagation direction. Combination of a half sinusoidal distributed and a slow coupling schmes was used for narrow bandwidth and small side-lobes. Simulation showed 1.5 nm passband at 1.5507 $\mu\textrm{m}$ and the side-lobes were suppressed more than 20 dB which is two times larger than that of a constant coupling filter. A monolithic two-channel wavelength demultiplexer was proposed and theoretically investigated.