식물플랑크톤 생장이 소양호 수층의유기물 분포에 미치는 영향

조영근,이동훈,김상종 ( Young gun Jo,Dong Hun Lee,Sang Jong Kim ) 한국하천호수학회 1995 생태와 환경 Vol.28 No.2

In oder to estimate the influence of primary production on the distribution pattern of organic matter in Lake Soyang, general physico-chemical factors, primary productivity, concentration of POC and DOC, sedimentation rate of POC and the decomposition rate of phytoplankton biomass were measured from Feb. to Oct., 1993. From Feb. to Apr. the productivity by phytoplankton was low, but the resuspension of sediment materials brought high level of organic carbon into the watercolumns. Afterward primary production played major role in the supply of organic carbon. The productivity was highest in Sep. and summed upto 154. 1g-C·m^-2 during the term from May to Sep. From the value, 15.8g-C·m^-2 of exudate and the decomposition product(16.6∼33.2g-C ·m^-2) was added to the epilimnetic DOC pool, and 7.2g-C ·m^-2 of phytoplankton biomass to epilimnetic POC pool. But 86.3∼102.9g-C·m^-2 of it sinked into meta- and hypo-limnetic zone, and 11.6g-C·m^-2 settled down to sediment layer. Thus 79.5 g-C·m^-2 which corresponds to 52% of the amount of the produced, remained in the watercolumn.

C- 형 탄소섬유와 Hollow - 형 탄소섬유의 특성

조영근,김철중,인세진,유승곤,이보성 ( Y . G . Jo,C . J . Kim,S . J . In,S . K,Ryu,B . S . Rhee ) 한국화학공학회 1991 춘계학술발표논문집 Vol.- No.-

Underwater Image Dehazing via Unpaired Image-to-image Translation

조영근,Hyesu Jang,Ramavtar Malav,Gaurav Pandey,김아영 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.3

Underwater imaging has long been focused on dehazing and color correction to address severe degradation in the water medium. In this paper, we propose a learning-based image restoration method that uses Generative Adversarial Networks (GAN). For network generality and learning flexibility, we constituted unpaired image translation frameworks into image restoration. The proposed method utilizes multiple cyclic consistency losses that capture image characteristics and details of underwater images. To prepare unpaired images of clean and degraded scenes, we collected images from Flickr and filtered out false images using image characteristics. For validation, we extensively evaluated the proposed network on simulated and real underwater hazy images. Also, we tested our method on conventional computer vision algorithms, such as the level of edges and feature matching results.

환경수계 레지오넬라균 오염 지표의 메타분석

조영근,Zo, Young-Gun 한국미생물학회 2013 미생물학회지 Vol.49 No.4

To identify risk factors for Legionella contamination, water quality variables routinely measured in examination of natural and city waters were meta-analyzed for significance of correlation to Legionella incidences. For evaluation of abundance of Escherichia coli as a risk factor, which is currently used as an indicator of Legionella contamination in an official guideline in Korea, odds ratio (OR) of above-cutoff total coliform counts for Legionella presence/absence was used as the effect size in the meta-analysis. The OR was estimated as 1.05 (0.36-3.12, 95% CI), and the probability of having identical odds reached 0.92. Also, ORs from individual studies showed significant heterogeneity (P=0.008), which contributed to 63% of total variance of the ORs. In the case of heterotrophic plate count (HPC), the OR for Legionella presence/absence was 2.72 (2.04-3.63) with highly significant deviation from identical odds (P<0.0001). ORs from different studies were seemingly homogeneous ($Q_{df=8}$=12.7, P=0.12). Turbidity and concentrations of chlorine, iron ion and cupper ion were other routine variables that could be considered as risk factors. However, statistical measures from different studies were not uniform enough to develop an appropriate effect size while the number of studies reporting the variables was also small (3-5). In conclusion, HPC appeared to be appropriate as indicator of Legionella contamination, rather than fecal bacteria contamination. HPC may imply abundance of habitats (amoebas and biofilms) of Legionella in water. This result warrants further studies for standardizing protocols and cutoff values to infer Legionella risks from HPC.

도심지역에서의 로봇의 위치추정과 항공사진의 모호성에 대한 고찰

조영근,김아영 제어로봇시스템학회 2015 제어로봇시스템학회 각 지부별 자료집 Vol.2015 No.12

로봇의 장기적 자율주행을 위한 다중 시간 영상의 변환 방법

조영근,김아영 제어로봇시스템학회 2018 제어로봇시스템학회 각 지부별 자료집 Vol.2018 No.11

생석회 처리가 토양 세균의 생존과 군집구조에 미치는 영향

조영근,Zo, Young-Gun 한국지하수토양환경학회 2012 지하수토양환경 Vol.17 No.1

When quicklime is added into soil for various purposes, abrupt changes in soil chemistry may affect essential ecological functions played by indigenous bacterial communities in soil. The magnitude of influence was estimated by observing changes in abundance and diversity of soil bacteria after quicklime treatment. When several soil samples were treated up to 20% (w/w) quicklime, plate count of viable cells ranged $10^2{\sim}10^3$ CFU $g^{-1}$, showing a reduction of more than $10^4$ times from viable counts of the untreated sample. Diversity of the bacterial isolates that survived after quicklime treatment was analyzed by conducting $GTG_5$ rep-PCR fingerprinting. There were only two types of fingerprints common to both 5% and 20% quicklime samples, implying that bacteria surviving at different strength of quicklime treatment differed depending on their tolerance to quicklime-treated condition. Isolates surviving the quicklime treatments were further characterized by Gram staining and endospore staining. All isolates were found to be Gram positive bacteria, and 85.4% of them displayed endospores state. In conclusion, most bacteria surviving quicklime treatment appear to be endospores. This finding suggests that most of ecological functions of bacteria in soil are lost with quicklime treatment.

Characterization of Phylogenetic Incongruence among Protein Coding Genes of Vibrio Strains Pathogenic to Humans

조영근,Zo, Young-Gun The Microbiological Society of Korea 2013 미생물학회지 Vol.49 No.4

Lateral gene transfer (LGT) of genes from other bacteria into Vibrio cholerae is expectable because of the pronounced natural competence of the bacterium. In this study, quantitative aspects of LGT among the three species of Vibrio pathogenic to humans were characterized. Genome sequences of V. cholerae N16961, V. parahaemolyticus RIMD2210633, V. vulnificus CMCP6, and Escherichia coli K12 substrain MG1655 were analyzed to determine orthologous quartets of protein coding genes present in all four genomes. Phylogenetic analyses on the quartets were conducted to resolve vertical versus lateral patterns of gene polymorphisms based on congruence versus incongruence of phylogenetic trees. About 70% of the quartets could be resolved as either cohesive topology (75%) or LGT tree topologies (25%). The amount of LGT genes in Vibrio spp. appeared to be abnormally high for a genus and comparable to those of families. Patched distributions of LGT from different donors were observed on a chromosome. In the small chromosome of V. cholerae, physical linkages among LGT loci spanned half the length of the chromosome. Either accumulative selection for the donor alleles in LGT or presence of large-scale LGT events was hypothesized. These findings warrant further studies on the nature of donor-specificity of LGT alleles and its influence on evolution of Vibrio virulence to humans.

Reductive Divergence of Enterobacterial Repetitive Intergenic Consensus Sequences among Gammaproteobacteria Genomes

조영근 한국미생물학회 2011 The journal of microbiology Vol.49 No.1

Enterobacterial repetitive intergenic consensus (ERIC) sequence is a transcription-modulating, nonautonomous,miniature inverted-repeat transposable element. Its origin and the mechanism of highly varying incidences,limited to Enterobacteriaceae and Vibrionaceae, have not been identified. In this study, distribution and divergence of ERICs along bacterial taxonomic units were analyzed. ERICs were found among five families of gammaproteobacteria, with the copy numbers varying with exponential increments. The variability was explained by genus (45%) and species (36%) affiliations, indicating that copy numbers are specific to subfamily taxa. ERICs were interspersed in genomes with considerable divergences. Locations of ERICs in a genome appeared to be strongly conserved in a strain, moderately in a species or a genus, and weakly in a family. ERICs in different species of a genus were from the identical population of sequences while ERICs in different genera of a family were nearly identical. However, ERICs in different families formed distinct monophylectic groups, implying vertical transmission of diverging population of sequences. In spite of large difference in copy numbers, overall intra-genome evolutionary distances among ERICs were similar among different species, except for a few genomes. The exceptions substantiated hypotheses of genetic drifts and horizontal gene transfers of mobility capacity. Therefore, the confined, variable distribution of ERIC could be explained as a two-step evolution: introduction and proliferation of ERIC in one of the progenitors of gammaproteobacteria, followed by vertical transmission under negative selection. Deterioration of sequences and reduction in copy number were concluded to be the predominant patterns in the evolution of ERIC loci.

국내 발생 삼일열 말라리아 원충 개체군의 유전형 변동과 진화의 경향

조영근 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

삼일열 말라리아는 1970년대 국내에서 완전에서 완전 박멸된 것으로 선언되었지만, 1993년 휴전선 근무 군인 중 환자가 발생한 이후 감염빈도가 급증하여, 현재 연간 약 1,000명 내외의 감염환자를 발생시키는 토착화 상태에 접어들었다. 북한 지역으로부터 Plasmodium vivax에 감염된 Anopheles sinensis 복합종의 전파 및 토착화된 전파과정의 양태를 파악하기 위하여, 진화 중립적 마커로 간주되는 microsatellite 43 자위를 이용하여 1996~2011년 사이 국내 발생 삼일열 말라리아 환자의 혈액에 함유된 P. vivax 유전체의 유전형 변동을 조사하였다. 1990년대의 개체군 구조는 대체로 clonal하였으나, 2002년 이후 2개 이상의 계통이 다른 원충 개체군이 분포하였고, 2006년 이후 다중 clone에 의한 감염과 유전형 다양성이 증가하였다. 2010~2011년간 환자를 감염한 원충들은 제한적 유전형 재조합이 확인되었다. P. vivax 개체군은 경기북부 지역에 토착화하여, 주로 지역적으로 고립된 증식 영역을 가지며 낮은 빈도의 이형간 유성생식을 일으키는 메타개체군을 형성하여 진화하는 것으로 사료된다.