• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.37-38
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• 2017

금속으로 이루어진 긴 선이나 구에 대한 전자파 산란 특성을 계산할 때, 산란 계산 속도를 개선하기 위해 사용하는 고성능 컴퓨팅(HPC) 기반 병렬 처리 특성을 제시한다. 산란 행렬 생성, 가우스 소거법, 산란파 계산 등으로 이루어진 전자파 산란 문제는 병렬 처리를 통해 계산 속도를 높일 수 있다. 산란 문제의 계산 절차를 분석하여 병렬화에 유리한 계산 작업을 분류한 후 OpenMP 기반 병렬화를 적용한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.487-493
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• 1994

Moment distribution procedure in the elastic analysis of rigid frames can be easily expressed with the adjusting moment equations(or relaxation equations) by using the concept of total adjusting moment at each joint after infinite cycles of moment distribution. Adjusting moment equations are a set of simultaneous equations from which the total adjusting moments at each joints after infinite cycles of physical relaxation can be determined. The form of simultaneous equations is a kind of relaxation equations and can be easily solved by the hand calculators. A unique and simplified procedure for the influence line analysis of a continuous beam is presented as an application of the method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.1 s.173
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• pp.225-231
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• 2000

Dimensional synthesis of planar and spatial mechanisms mostly requires solution-finding, procedure for a system of polynomial equations. In case the system is nonlinear, numerical techniques like Newton-Raphson are often used. But there are no logical ways for finding all possible solutions in such iterative methods. In this paper, algebraic elimination is used to get all solutions for the synthesis of 5-SS spatial mechanism with seven prescribed positions. The proposed algorithm is more suitable for computer implementation and takes less time than existing one. Two numerical examples are given to demonstrate the implemented algorithm.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.1-4
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• 2003

Two antioxidative compounds in Chrysanthemum boreale were isolated by a bioassay using a 2, 2-diphenyl-1-picrydrazyl(DPPH) free radical. They were identified as apigenin, linarin(acacetin-7-O-rutinoside) on the basis of $^1H\;and\;^{13}C-NMR$ and MS data. The DPPH radical scavenging activity$(RC_{50}:\;13.3{\mu}g)$ of apigenin was similar to that of ${\alpha}-tocopherol\;(12.1{\mu}g)$ and L-ascorbic acid$(13.1{\mu}g)$

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3087-3093
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• 2009

Digital filters are indispensible element in digital signal processing area. The performance of digital filter based on adding and multiplying operation, such as computational speed and power consuming is determined by the orders and coefficients of filter which has on effect area of semiconductor chip when it is implemented by VLSI technology. In this research, in order to performance improvement of digital filter, we proposed the algorithm to speed-up the operation of digital filter associated with the minimum signed digit representation of binary number system and method to simplify the digital filter design associated with common subexpression elimination. The performance of proposed method is evaluated by the computational speed and design-simplicity by experimental implemented digital filter on FPGA.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.2
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• pp.237-247
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• 2001

강상판교는 부재수가 많고 구조적 거동이 복잡하여 재래적인 단일수준 (CSL) 알고리즘을 이용하여 최적화하는 것이 매우 어렵기 때문에 본 연구에서는 강상판교를 효율적으로 최적화하기 위해 다단계 최적설계 (MLDS) 알고리즘이 제안되었다. 강상판교를 주형과 강상판으로 나누기 위해 등위법이 사용되었고, 시스템 최적화를 위하여 설계 변수를 줄이는 분해법이 사용되었다. 효율적인 최적설계를 위해 다단계 최적설계 알고리즘은 제약조건 소거기법(Constraint Deletion)과 응력 재해석 같은 근사화 기법을 도입하였다. 변위해석을 위한 제약조건 소거기법은 교량의 최적화에 효율적인 것으로 검증되었고, 제안된 응력 재해석 기법 또한 설계민감도 해석을 필요로 하지 않으므로 매우 효율적이다. MLDS 알고리즘의 적용성과 강건성은 다양한 수치예제를 사용하여 기존의 단일수준 알고리즘과 비교하였다.

• Food Science and Preservation
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• v.11 no.2
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• pp.201-206
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• 2004

The activities of antioxidation and alcohol dehydrogenase in hibitionin methanol extracts of thirty two medical herbs were tested using the method of DPPH activity, nitrite scavenging effect and alcohol dehydrogenase assay in vitro. In DPPH method, Eugenia caryophyllata, Thea sinensis, Paeonia suffruticosa, Alnus japonica showed over 90 % of free radical scavenging activities. The nitrite scavenging ability appeared Zanthoxylum bungeanum, Alnus japonica, Thea sinensis, Hovenia dulcis(cortex) and Illicium verum showed the high value. In connection with in vivo alcohol metabolism, thirteen medicinal herbs were screened for inhibition. As a reasult, we found significant inhibition of ADH by methanolic extracts of Glycyrrhiza uralensis, Pueraria thunbergiana(radix), Alnus japonica. These results indicate that the antioxidative effect was strongly related with alcohol dehydrogenase inhibitor; Thea sinensis and Alnus japonica.

• Journal of Life Science
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• v.30 no.11
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• pp.956-964
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• 2020

The radical scavenging activity measurement system linked with liquid chromatography (LC) is a useful tool for identifying the radical scavenging active compound in a sample composed of numerous compounds such as plant extracts. Using this system, DPPH and ABTS radical scavenging activity were measured on extracts of Ulmus pumila cortex, which is known as an herbal medicine with antioxidant activity. Mass spectrometry (MS) was performed on the identified radical scavenging active compounds to identify the four components estimated to be procyanidin B2, procyanidin B3, catechin-7-O-β-D-apiofuranoside, and catechin-5-O-β-D-apiofuranoside, respectively. In order to compare the relative contents between extract samples, multiple reaction monitoring (MRM) mode analysis conditions were set for the four compounds in order to examine the possibility of comparing the content of radical scavenging active compounds in Ulmus pumila cortex extract using LC-MS/MS. As a result of the relative content comparison, it was found that the higher the ethanol concentration of the extraction solvent, the higher the content of radical scavenging active compounds. As with the results of measuring the radical scavenging activity of each extract, it was confirmed that the content difference of three of the compounds (all except the compound estimated as procyanidin B3) was not significantly observed in the extracts with an ethanol concentration of 50% or more.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.83-83
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• 2018

최근 매실나무를 기주로 한 겨우살이의 인공재배에 성공함에 따라, 식 의약품과 화장품의 소재 및 산업화 가능성을 확인하기 위해 80% 에탄올 및 증류수 초음파추출물의 총 폴리페놀 플라보노이드 함량 및 DPPH free radical 소거능을 측정하였다. 경기도 남양주시에서 인공재배한 매실나무겨우살이(동결건조) 및 강원도 홍천에서 채취한 자연산 굴참나무겨우살이(열풍건조, $30^{\circ}C$, 7day)의 80% 에탄올, 증류수 초음파추출물에 대한 총 폴리페놀 및 플라보노이드함량 그리고 DPPH free radical 소거능을 측정한 결과, 시료의 농도에 비례하여 총 폴리페놀과 플라보노이드 함량 그리고 DPPH free radical 소거능이 증가하였다. 총 폴리페놀 함량은 매실나무겨우살이의 80% 에탄올 추출물이 5,000ppm에서 $192.63{\mu}g/ml$로 가장 많았으며, 굴참나무겨우살이의 물 추출물이 100ppm에서 $4.86{\mu}g/ml$로 가장 낮고 매실나무겨우살이가 모든 용매에서 더 많은 폴리페놀을 함유한 것으로 확인되었다. 총 플라보노이드 함량은 굴참나무겨우살이의 80% 에탄올 추출물이 5,000ppm에서 $83.59{\mu}g/ml$로 가장 높았으며, 매실나무겨우살이 물 추출물이 $4.6{\mu}g/ml$로 가장 낮았고 굴참나무겨우살이가 모든 용매에서 더 많은 플라보노이드를 함유한 것으로 확인되었다. DPPH free radical 소거능은 80% 에탄올 추출물 5,000ppm에서 매실나무겨우살이 81.75%로 시료 중 가장 높았고, 굴참나무겨우살이 물 추출물 100ppm이 3.55%로 가장 낮음을 확인할 수 있었다. 본 연구 결과에 따르면, 겨우살이를 초음파추출법으로 추출할 때, 80% 에탄올 초음파추출물이 더 많은 폴리페놀을 함유하여 80% 에탄올 추출물이 물 추출물보다 비교적 적합하였다. 80% 에탄올로 초음파추출 하였을 때 동결건조 한 매실나무겨우살이가 열풍건조한 자연산 굴참나무겨우살이보다 더 많은 폴리페놀을 함유하고 있고, 더 높은 DPPH free radical 소거능을 보여줌에 따라 식 의약품 그리고 화장품의 소재화 및 산업화의 가능성이 높음을 확인할 수 있었다.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.985-994
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• 2019

Muberry (Morus alba L.) leaves fermented with Hericium erinaceum mycelium (MA-HE) were assessed for the protection against oxidative modification of antioxidant enzymes, Cu,Zn-superoxide dismutase(SOD) and ceruloplasmin(CP). MA-HE were shown to significantly inhibited oxidative modifications and inactivations of Cu,Zn-SOD and CP induced by peroxyl radical. Antioxidant activity of MA-HE evaluated using peroxyl radical scavenging assays. MA-HE showed 44.03% of peroxyl radical scavenging activity at $100{\mu}g/mL$. Thus, MA-HE protect the antioxidant enzymes from oxidative damage by the scavenging peroxyl radicals. The results suggested that MA-HE was effectively removed reactive oxygen species in cells, thereby protecting cytotoxicity caused by oxidative stress.