• 대한수학회논문집
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• 제28권4호
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• pp.833-850
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• 2013

We present an algorithm for computing the Hausdorff distance between two parametric curves in $\mathbb{R}^n$, or more generally between two sets of parametric curves in $\mathbb{R}^n$. During repeated subdivision of the parameter space, we prune subintervals that cannot contain an optimal point. Typically, our algorithm costs O(logM) operations, compared with O(M) operations for a direct, brute-force method, to achieve an accuracy of $O(M^{-1})$.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2007년도 춘계학술대회
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• pp.7-10
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• 2007

Since 2003, the biggest trade partner of South Korea has not been America but China. China appears to be a strong competitor of South Korea in every field of international market and even in IT industry, which has been one of the most competitive field of Korean Economy. IT Industry is now becoming a driving locomotive of economy in South Korea and China. It is reported that the IT gap between South Korea and China is shorten to be 1.7 years in 2006, from 2.6 years in 2003 and will be within one year in 2010. China has been aware of the urgent need of developing electronic and information industry in order to improve its productivity. In the results of the efforts to develop its IT industry, China has achieved average 25% yearly growth rate of IT manufacturing industry since 1991. Since 2004, South Korea has pursued IT 839 strategy. How South Korea and China can sustain the continuous development of IT industry. South Korea IT is expected to utilize China's through the mutual cooperation, which results in mutual benefit. To achieve the mutually benefited cooperation and specially to result in Small & Medium sized Korean companies' cooperation with China's, China is expected to improve the market system and create an environment of admitting intellectual property.

• Bulletin of the Korean Chemical Society
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• 제28권6호
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• pp.990-994
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• 2007

Bioassay-guided fractionation of the MeOH extract from the sponge Discodermia calyx collected off the coast of Jeju Island, South Korea, led to the isolation of a polyketide, icadamide C (1), along with previously reported theopederin K (3). Structure elucidation was performed by a combination of high resolution mass and 2D-NMR (principally COSY, HMBC, HSQC, and NOESY) spectroscopy. Stereochemistry of compound 1 was determined as 2R*, 3R*, 6R*, 10S*, 11S*, 12R*, 13S*, 15R* and 2'S by NMR data and Marfey analysis. Isolated metabolites displayed potent cytotoxic activity against a small panel of five human solid tumor cell lines with ED50 values of less than 0.1 μg/mL.

• 한국어류학회지
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• 제22권3호
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• pp.201-205
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• 2010

2008년 8월 경남 통영에서 강담돔과 돌돔의 자연교잡종 1개체가 발견되어 형태 및 유전적 특정을 강담돔 및 돌돔과 비교하였다. 형태적으로 본 총은 체측에 선명한 검은색 둥근 점을 많이 가지며 동시에 4개의 연한 가로줄을 가져 강담돔과 비슷하였다. 강담돔 및 돌돔의 계수 계측형질이 거의 일치하였으나, 체장에 대한 배지느러미길이 비에서 자연교잡종(26.7%)은 돌돔(17.2~23.6%)보다 강담돔(26.4%)에 더욱 가까웠다. 미토콘드리아 DNA 16S rRNA 510 bp를 이용한 분자분석에서 자연교잡종은 형태결과와는 달리 강담돔(d=0.020)보다 돌돔(d=0.000~0.010)에 더욱 가까웠다. 본 연구결과를 통해 경남 통영에서 발견된 자연교잡종은 암컷 돌돔과 수컷 강담돔 사이에서 태어난 것으로 추정된다.

• Journal of Species Research
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• 제5권1호
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• pp.188-200
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• 2016

During recent screening to discover indigenous prokaryotic species in South Korea, a total of 31 bacterial strains assigned to the class Gammaproteobacteria were isolated from a variety of environmental samples including soil, tidal flat, freshwater, seawater, and plant roots. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 31 species have been described in South Korea; therefore 5 species of 3 genera in the order Alteromonadales, 11 species of 3 genera in the order Pseudomonadales, 8 species of 6 genera in the order Enterobacteriales, 2 species of 1 genera in the order Vibrionales, 1 species of 1 genera in the order Oceanospirillales, 3 species of 3 genera in the order Xanthomonadales, and 1 species in the order Spongiibacter_o within the Gammaproteobacteia are reported for proteobacterial species found in South Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.

• 한국균학회지
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• 제12권2호
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• pp.53-58
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• 1984

하기재배(夏期栽培)에 알맞는 느타리버섯은 동남아세아(東南亞細亞) 및 인도(印度)에 자생(自生)하는 느타리버섯(Pleurotus spp.) 6균주(菌株)를 수집(蒐集)하여, 볏짚배지(培地)에서의 균사생장(菌絲生長) 정도(程度), 발용온도(發茸溫度) 및 여름철 기후하(氣候下)에서 자실체(字實體) 생산력(生産力) 등(等)을 조사(調査)하여 선발(選拔) 하였다. 새로선발(選拔)된 Pleurotus sajor-caju ( Fr.) Sing. (ASI 2070)은 시험(試驗)된 균주(菌株) 중(中) 볏짚배지(培地)에서 가장 양호한 균사생장(菌絲生長)을 보였고, 자실체수량(子實體收量)은 $13.7kg/m^2$으로 높았다. 발용온도범위(發茸溫度範圍)는 $10{\sim}35^{\circ}C$ 였으며 최적온도(最適溫度)는 $20{\sim}25^{\circ}C$였다. 이와같은 시험결과(試驗結果)는 농가재배(農家栽培)로 실증(實證)하였으며 이버섯을 "여름느타리버섯"으로 명명(命名)하였다.

• 생명과학회지
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• 제17권3호통권83호
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• pp.386-395
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• 2007

본 연구는 1999년에서 2001년도 걸쳐서 3년간 국내에서 분리된 환자유래 장염비브리오 18균주와 일본 후쿠오카 지역에서 2002년도에 환자에서 분리한 장염비브리오 9균주 등 총 27균주에 대하여 toxR 유전자의 검출, 혈청형별 검사, 약제내성의 양상, tdh, trh1 및 trh2 유전자의 보유상태 및 urease 생성성을 살펴보고, 혈청형 O3:K6 균주에 대하여 TDH의 생성성 검사, tdh 양성균주의 RFLP 형별, ORF 8의 분포, PFGE법과 RAPD법을 실시하였으며 결과는 다음과 같다. 1. 한국 및 일본의 환자유래 균주 대부분에서 urease음성이었으며, toxR 유전자로 확인 동정하였고 혈청형의 분포는 국내 분리 주의 O3:K6, O4:K9, O6:K46, O3:K57, O5:Kl5와 일본 분리주의 O3:K6, O1:K38, O4:K68, O4:Kl2의 혈청형으로 나타났다. 2. 항생제 감수성 시험에서는 vancomycin과 oxacillin은 27균주 (100%), penicillin은 26균주 (96.3%)로 높은 내성을 나타내었고, 14균주 (51.9%)가 4가지 이상의 항생제에 다제내성을 나타내었다. 항생제의 내성양상은 6종류로 혈청형에 관계없이 vancomycin, oxacillin, penicillin에 내성을 나타내는 V형이 15균주 (55.6%)로 가장 많이 나타났다. 3. tdh 유전자는 26균주가 PCR법과 DNA probe hybridization법의 결과에서 양성으로 나타났으며, urease양성이었던 일본 환자유래 혈청형 O3:K6 1균주만이 tdh유전자 음성, trh2 유전자 양성을 나타냈다. 혈청형 O3:K6의 TDH 생성성역가는 전 균주가 256배에서 2,048배 정도로 나타났으며, RFLP 양상은 모든 균주가 11.5 kb와 4.3 kb에 tdh 유전자를 보유하고 있었다. 또한 혈청형 O3:K6 균주들은 RAPD법과 PFGE법으로 유전자형별을 비교 검토한 결과 8형으로 거의동일한 유전자형별의 결과를 나타내었다. 4. ORF 8의 분포는 혈청형 O3:K6 전 균주에서 양성이었고, 특히 혈청형 O6:K46 4균주 모두에서 ORF 8 양성을 나타내어 새롭게 나타난 유행균주일 가능성을 시사 하였다. 따라서 ORF 8 유전자의 검출은 범세계적으로 유행하는 균주들을 동정하는데 있어 genetic marker로서 매우 유용한 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.673-679
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• 2004

A microbial cryoprotectant formulation using a W/O/W multiple emulsion system was developed. The psychrotolerant microorganism, B4, isolated from soil in South Korea, was observed by the drop freezing method, in which the microorganism sample inhibited ice nucleation activity. The antifreeze activity was eliminated when the microorganism sample was treated with protease, indicating that the antifreeze activity was due to the presence of antifreeze protein. The result of the l6S rDNA sequencing indicated the B4 strain was most closely related to a species of the genus Bacillus. Culture broth of B4 strain (Bacillus sp.) and rapeseed oil containing 1 % polyglycerine polyricinolate (PGPR) were used as core and wall material, respectively. The most stable W/O emulsion was prepared at a core/oil ratio of 1:2. The highest W/O/W emulsion stability was achieved when the primary emulsion to external aqueous phase containing 0.5% caster oil polyoxyethylene ether $(COG25^{TM})$ ratio was 1:1. Microcrystalline cellulose showed better W/O/W emulsion stability than other polymer types. The viability of cells in a W/O/W emulsion was higher than free cells during storage at $37^\circ{C}$. An acidic pH and UV exposure decreased the viability of free cells, but cells in W/O/W emulsion were more stable under these conditions.

• Animal cells and systems
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• 제15권1호
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• pp.73-78
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• 2011

Estimating the habitat potential of inland forest patches for birds requires the modeling of species-area relationships, or relationships between habitat size and numbers of bird species in each patch. The accurate estimation of speciesarea relationships significantly reduces the effort required to recognize the number of species living in each patch. The objective of this study was to estimate the relationship between forest patch size and bird species diversity in Dangjin County, in northwest South Korea, based on the sizes of inland forest patches. KOMPSAT-2 images were obtained and ortho-rectified to construct a map of the target forest patches. The numbers of birds per patch were surveyed four times: August 2008, September 2008, February 2009 and May 2009. Regression models were derived to explain the relationships between the numbers of bird species and patch size. A model that was derived using data from all four observation periods had the highest coefficient of determination ($R^2$). According to these models, the numbers of bird species at first increased linearly with increasing patch size; however, the curve then plateaued. Our model including observations from four seasons will be useful for estimating the numbers of bird species in other inland forest patches in South Korea.

• Asian Journal of Atmospheric Environment
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• 제12권3호
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• pp.204-214
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• 2018

Indoor air quality was investigated in homes and daycares located in areas with heavy traffic in Seoul, South Korea from November 2013 to January 2014. Indoor and outdoor air quality measurements were collected for 48 hours in four children's homes and daycare centers. The I/O ratio (Indoor to outdoor ratio) for each major air pollutant ($NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$) was calculated, and $NO_2$ and $PM_{10}$ concentration profiles were analyzed based on indoor activity diaries recorded during the 48 hours. Most I/O ratios for $NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$ at daycare centers were less than one. At homes, I/O ratios for black carbon, $PM_{10}$, and $PM_{2.5}$ were less than one; however, most I/O ratios for $NO_2$ were greater than one due to the usage of gas stoves. The children's exposure to indoor air pollutants was calculated using a time-weighted average exposure method, and the daily intake level for each pollutant was determined.