• 한국지형학회지
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• 제27권1호
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• pp.21-31
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• 2020

Planting pine trees on the coastal dunes has been carried out along the East coast as well as West coast of South Korea. Although the artificial forestation has been regarded as a good policy that help to protect the coastal area from natural disasters, but its real effect to the landscapes is still unknown. In this study, we have installed a monitoring site with an automated weather station to study requirements for dune formation and its environmental changes in Osan beach, Yangyang-Gun, Gangwon Province. We analyzed the meteorological data collected from 2010 to 2019 and vegetational changes in the study area. As a result, the wind speed is decreased by around 30% and the pine-covered area is increased by around 300m² after planting Japanese Black Pine in 2015. At present, it seems that the eolian transport of sand particle is minimal, because the dominant winds are the westerly winds which is not landward but seaward, and because the surface roughness length is about 0.5m which is similar to that in the deciduous forest.

• 대한화장품학회지
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• 제39권3호
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• pp.251-257
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• 2013

본 연구는 자외선 차단지수(Sun protection Factor, SPF) 측정 시험에서 피험자의 안전을 확보하고 정확한 시험결과를 통해 향후 자외선 조사시험의 기초 데이터 확보 및 연구자료 마련을 목적으로 하였다. 피부유형 기준표에 따라 피험자의 피부유형 I, II, III 형에 해당되는 피험자 395명을 대상으로 하였다. 색차계를 이용하여 피부색을 측정한 뒤 ITA (Individual Typology Angle) 값을 계산하고 그 값이 28 이상인 사람을 대상으로 편안한 자세를 취하도록 하여 자외선을 60 s 간 조사한 후 24 h 뒤 피험자의 홍반 상태를 판정하였다. 전면에 홍반이 나타난 부위에 조사한 UVB의 광량 중 최소량을 최소홍반량(Minimal Erythema Dose, MED)으로 하였다. 통계학적 분석은 Statistical Package for the Social Sciences 프로그램을 사용하였다. 피부 유형이 높아질수록 MED 값이 증가하여 피부색이 어두워질수록 MED가 증가한다는 결과를 얻을 수 있었다. 또한 여성이 남성보다 높은 MED로 여성이 남성보다 어두운 피부유형을 가진 것으로 나타났고, 연령별 MED는 피부타입별 모든 연령대에서 연관성이 없었으나 이 같은 결과를 단정 짓기에는 성별, 연령대별 피험자 수가 적어 통계적 유의성을 뒷받침하는데 한계가 있을 것으로 생각된다. 본 연구를 통해 얻은 피부유형별 MED 측정값은 자외선 차단제를 사용하기 전 MED 값을 예상하여 자외선차단제의 효능 평가 시 비교, 판독을 할 수 있는 기준이 되므로 임상에 안전하게 적용할 수 있는 기초자료로써 유용하게 쓰일 수 있을 것이다.

• 한국입자에어로졸학회지
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• 제8권4호
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• pp.151-160
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• 2012

Health effects caused by the ultrafine particles in ambient air are great concern to the public health, and the strict measuring and monitoring of the ambient aerosol are required. In this work, the characteristics of the aerosol size distribution in Pohang province are studied. Optical particle counters (Grimm APS 1108 and 1109) were used to measure the aerosol size distribution in the area. Locations near the national monitoring site located in the industrial and the residence area were selected for the measuring sites of this study, and the locations in border area between the industry and the residence were selected for the reference of the comparison. In the industry site, it is found that the concentration of aerosol particles near the size of 5 ${\mu}m$ appear characteristically and the fluctuations in concentration with respect to time are minimal. The mass concentration of the aerosol above 10 ${\mu}m$ in diameter in the industry area was found to fluctuate significantly. The mass portion of $PM_{10}$ and PM2.5 to TSP in the residence area were 83% and 51% respectively. In the industrial regional, it was found that the mass portion of PM10 and $PM_{2.5}$ to TSP were 76% and 35% respectively. In the boundary area the mass portion of $PM_{10}$ and $PM_{2.5}$ to TSP were 78% and 54% respectively.

• 한국식품영양학회지
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• 제33권5호
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• pp.524-531
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• 2020

The purpose of this study was to evaluate the quality properties of Meju prepared by inoculating two strains of Bacillus amyloliquefaciens HJ5-2, and Aspergillus oryzae PS03. The three soybean varieties that include Daewonkong, Daechan, and Saedanbaek were used in this experiment. The fermentation temperature during the Meju aging varied at 20℃, 30℃, and 40℃, respectively. The physicochemical analysis of the soybeans, showed that the cured protein and fat contents were 34.83~43.49% and 12.91~18.90%, respectively. The pH and total acidity were 6.47~6.93 and 0.11~1.22%, respectively. The change in appearance of the Meju was that the yellow-green mold was well formed on seven days at fermentation temperature of 20℃ and 30℃, but at 40℃, there was minimal mold formation and cracking of the surface. The amino nitrogen content was highest on the Daechan Meju at 621.83 mg% for seven days. The amylase increased as the fermentation period increased in all samples, and the protease increased rapidly until the first day of the fermentation, and then gradually increased thereafter. The total number of bacteria increased or decreased as the fermentation proceeded to 6.66~10.07 log CFU/g. The mold counts increased with increasing fermentation period in the range of 6.38~8.79 log CFU/g.

• Carbon letters
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• 제28권
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• pp.47-54
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• 2018

High surface carbon aerogels with hierarchical and tunable pore structure were prepared using ionic liquid as carbon precursor via a simple salt templating method. The as-prepared carbon aerogels were characterized by nitrogen sorption measurement and scanning electron microscopy. Through instant visual observation experiments, it was found that salt eutectics not only serve as solvents, porogens, and templates, but also play an important role of foaming agents in the preparation of carbon aerogels. When the pyrolyzing temperature rises from 800 to $1000^{\circ}C$, the higher temperature deepens the carbonization reaction further to form a nanoporous interconnected fractal structure and increase the contribution of super-micropores and small mesopores and improve the specific surface area and pore volume, while having few effects on the macropores. As the mass ratio of ionic liquid to salt eutectics drops from 55% to 15%, that is, the content of salt eutectics increases, the salt eutectics gradually aggregate from ion pairs, to clusters with minimal free energy, and finally to a continuous salt phase, leading to the formation of micropores, uniform mesopores, and macropores, respectively; these processes cause BET specific surface area initially to increase but subsequently to decrease. With the mass ratio of ionic liquids to salts at 35% and carbonization temperature at $900^{\circ}C$, the specific surface area of the resultant carbon aerogels reached $2309m^2g^{-1}$. By controlling the carbonization temperature and mass ratio of the raw materials, the hierarchically porous architecture of carbon aerogels can be tuned; this advantage will promote their use in the fields of electrodes and adsorption.

• 한국안전학회지
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• 제35권1호
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• pp.107-115
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• 2020

This paper introduces the first vital area identification (VAI) process for the physical protection of nuclear power plants (NPPs) during low power and shutdown (LPSD) operation. This LPSD VAI is based on the 3rd generation VAI method which very efficiently utilizes probabilistic safety assessment (PSA) event trees (ETs). This LPSD VAI process was implemented to the virtual NPP during LPSD operation in this study. Korea Atomic Energy Research Institute (KAERI) had developed the 2nd generation full power VAI method that utilizes whole internal and external (fire and flooding) PSA results of NPPs during full power operation. In order to minimize the huge burden of the 2nd generation full power VAI method, the 3rd generation full power VAI method was developed, which utilizes ETs and minimal PSA fault trees instead of using the whole PSA fault tree. In the 3rd generation full power VAI method, (1) PSA ETs are analyzed, (2) minimal mitigation systems for avoiding core damage are selected from ETs by calculating system-level target sets and prevention sets, (3) relatively small sabotage fault tree that has the systems in the shortest system-level prevention set is composed, (4) room-level target sets and prevention sets are calculated from this small sabotage fault tree, and (5) the rooms in the shortest prevention set are defined as vital areas that should be protected. Currently, the 3rd generation full power VAI method is being employed for the VAI of Korean NPPs. This study is the first development and application of the 3rd generation VAI method to the LPSD VAI of NPP. For the LPSD VAI, (1) many LPSD ETs are classified into a few representative LPSD ETs based on the functional similarity of accident scenarios, (2) a few representative LPSD ETs are simplified with some VAI rules, and then (3) the 3rd generation VAI is performed as mentioned in the previous paragraph. It is well known that the shortest room-level prevention sets that are calculated by the 2nd and 3rd generation VAI methods are identical.

• 생물환경조절학회지
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• 제16권2호
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• pp.135-141
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• 2007

인위적인 수분처리에 대한 묘고생장 결과 물푸레나무는 수분처리의 영향을 크게 받지는 않았으나, 토양수분이 감소할수록 생장이 감소하였고, 들메나무는 상대적으로 토양수분이 높은 처리구$(78{\sim}90%)$에서 높은 생장을 보였다. 물푸레나무와 들메나무의 근원직경 또한 토양수분이 감소할수록 생장이 감소하는 경향을 보였다. 물질생산량의 변화는 물푸레나무의 경우 잎, 줄기, 뿌리 등 건중량이 각 처리구별로 토양내 수분이 낮아질수록 통계적으로 유의성을 보이면서 감소하는 경향을 나타냈으며, 토양수분이 $78{\sim}90%(A)$인 처리구에서는 상대적으로 $18{\sim}30%(D)$ 처리구에 비해 약 2배 이상 높은 물질 생산량을 나타 냈다. 들메나무도 각 처리구간에 차이를 보이면서 A처리구와 D의 처리구에서는 통계적으로 유의성을 보였다. 이는 토양수분이 묘목의 수세 약화 및 잎을 포함한 조직의 연화 등 생리적인 부분에 영향을 미치는 것으로 생각된다. 물푸레나무와 들메나무의 엽 특성중 SLA는 토양수분처리에 따라 통계적으로 유의성을 보이진 않았지만 처리구간 수분함량이 적을수록 감소하는 경향을 나타냈다. 그러나 LAR과 LWR의 경우에는 각 처리구간 토양내 수분함량이 적을수록 통계적으로 유의성은 나타나지 않았지만 증가하는 경향을 나타냈다.

• The Plant Pathology Journal
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• 제38권5호
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• pp.541-549
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• 2022

Potato late blight caused by Phytophthora infestans is a destructive disease in Korea. To elucidate the genomic variation of the mitochondrial (mt) genome, we assembled its complete mt genome and compared its sequence among different haplotypes. The mt genome sequences of four Korean P. infestans isolates were revealed by Illumina HiSeq. The size of the circular mt genome of the four major genotypes, KR_1_A1, KR_2_A2, SIB-1, and US-11, was 39,872, 39,836, 39,872, and 39,840 bp, respectively. All genotypes contained the same 61 genes in the same order, comprising two RNA-encoding genes, 16 ribosomal genes, 25 transfer RNA, 17 genes encoding electron transport and ATP synthesis, 11 open reading frames of unknown function, and one protein import-related gene, tatC. The coding region comprised 91% of the genome, and GC content was 22.3%. The haplotypes were further analyzed based on sequence polymorphism at two hypervariable regions (HVRi), carrying a 2 kb insertion/deletion sequence, and HVRii, carrying 36 bp variable number tandem repeats (VNTRs). All four genotypes carried the 2 kb insertion/deletion sequence in HVRi, whereas HVRii had two VNTRs in KR_1_A1 and SIB-1 but three VNTRs in US-11 and KR_2_A2. Minimal spanning network and phylogenetic analysis based on 5,814 bp of mtDNA sequences from five loci, KR_1_A1 and SIB-1 were classified as IIa-6 haplotype, and isolates KR_1_A2 and US-11 as haplotypes IIa-5 and IIb-2, respectively. mtDNA sequences of KR_1_A1 and SIB-1 shared 100% sequence identity, and both were 99.9% similar to those of KR_2_A2 and US-11.

• Journal of Acupuncture Research
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• 제22권6호
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• pp.229-239
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• 2005

목적: 알레르기비염은 이환율이 높은 질환이다. 비폐색은 알레르기비염의 주요 증상으로 수면장애, 우울, 주의력 저하, 기억력 감퇴 등을 유발한다. 비염에 대한 침치료는 문헌에 언급되어 있고 임상에서 많이 사용되지만 잘 디자인된 임상연구는 많지 않다. 본 연구는 알레르기비염환자의 비폐색에 대한 침치료의 효과에 대해 알아보고자 하였다. 방법: 본 연구는 단일맹검, 무작위배정, 대조군연구로 치료혈은 영향(Il20), 상성(GV23), 합곡(IL4)으로 하였고, 유효성 평가는 음향비 강통기도검사를 통한 총비강용적, 총비강최소단면적의 변화로 하였다. 결과: 101명의 피험자가 연구를 종료하였으며 연령, 성별, 체중, 신장, 맥박, 호흡수, 지속성 비염의 중증도, 양성반응을 보인 항원의 수에서 대조군과 침치료군에서 차이는 없었다. 침치료군과 대조군 모두에서 치료직후 총비강용적이 유의성(침치료군: p=0.0007, 대조: p=0.0175)있게 증가하였고, 치료15 분후 침치료군에서 대조군에 비하여 증가된 총비강용적이 경계수준의 유의성(p=0.0871)으로 유지되었다. 침치료군과 대조군 모두에서 치료직후 총비강최소단면적이 유의성(침치료군: p<0.0001, 대조군: p=0.0005)있게 증가하였고, 치료15분후 침치료군에서 대조군에 비하여 증가된 총비강최소단면적이 경계수준의 유의성(p=0.0929)으로 유지되었다. 결론: 지속성 알레르기비염의 비폐색에 대한 침치료는 비강용적과 비강단면적을 증가시켜 비폐색을 완화시키는 효과가 있었으나 지속적인 효과에 대하여는 추가적 연구가 필요하다.

• 한국정보전자통신기술학회논문지
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• 제2권1호
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• pp.37-42
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• 2009

디지털 신호 처리 분야에서 디지털 필터는 필수불가결한 요소이다. 디지털 필터는 이진수의 곱셈 및 덧셈을 기본으로 하는 것으로 많은 연산량을 필요로 한다. 디지털 필터 내의 곱셈기는 VLSI 기술을 이용한 디지털 필터의 설계에 있어 반도체 칩 내부의 넓은 영역을 차지하고 전력의 대부분을 소비하며, 필터의 critical path를 결정하여 필터의 성능을 결정하는 중요한 요소로서 작용 한다. 본 연구에서는 특히 디지털 필터의 복잡성(complexity)를 해소하고 critical path를 줄여 필터의 연산속도를 증가시키기 위한 방법으로 2의 보수로서 표현되는 이진수를 CSD(canonical signed digit)와 MSD(minimal signed digit)로 동시에 변환하여 표현하는 방법을 제안하였다. 제안된 방법은 VHDL로 구현하고 임의의 필터에 적용하여 필터의 critical path가 감소하는 것을 보였다.