• Title/Summary/Keyword: Jong-Hwa AN

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Feeding Ecology of the White-spotted Conger Eel(Conger myriaster) in the Southern Sea of Korea (한국 남해 연안에 분포하는 붕장어(Conger myriaster)의 섭이생태)

  • Choi, Jung-Hwa;Choi, Sung-Hee;Kim, Jong-Bin;Park, Jeong-Ho;Oh, Chul-Woong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.4
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    • pp.282-288
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    • 2008
  • Feeding ecology of the white-spotted conger eel Conger myriaster in the Southern Sea of Korea was examined. Specimens were caught monthly from January 2004 to December 2006. Primary prey items of C. myriaster included fish, shrimp, and crabs. C. myriaster exhibited a nocturnal feeding strategy and preyed upon a wide range of pelagic fish groups(e.g., Engraulis japonicus, Glossanodon semifasciatus, and Maurolicus muelleri). This species was also an opportunistic feeder that exploited the available prey in each area(i.e., fish in the A area and shrimp in the B area). The composition of the diet of C. myriaster exhibited seasonal fluctuations that were related to food availability during each season. The observed ontogenetic shifts in diet were relatively clear, despite substantial overlap between the 10 cm and 20 cm groups of C. myriaster.

A STUDY OF A NUCLEAR HYDROGEN PRODUCTION DEMONSTRATION PLANT

  • Chang, Jong-Hwa;Kim, Yong-Wan;Lee, Ki-Young;Lee, Young-Woo;Lee, Won-Jae;Noh, Jae-Man;Kim, Min-Hwan;Lim, Hong-Sik;Shin, Young-Joon;Bae, Ki-Kwang;Jung, Kwang-Deog
    • Nuclear Engineering and Technology
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    • v.39 no.2
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    • pp.111-122
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    • 2007
  • The current energy supply system is burdened by environmental and supply problems. The concept of a hydrogen economy has been actively discussed worldwide. KAERI has set up a plan to demonstrate massive production of hydrogen using a VHTR by the early 2020s. The technological gap to meet this goal was identified during the past few years. The hydrogen production process, a process heat exchanger, the efficiency of an I/S thermochemical cycle, the manufacturing of components, the analysis tools of VHTR, and a coated particle fuel are key areas that require urgent development. Candidate NHDD plant designs based on a 200 MWth VHTR core and I/S thermochemical process have been studied and some of analysis results are presented in this paper.

Assessment of the Urban Heat Island Effects with LANDSAT and KOMPSAT-2 Data in Cheongju (LANDSAT과 KOMPSAT-2 데이터를 이용한 청주지역 도시열섬효과의 평가)

  • Na, Sang-Il;Park, Jong-Hwa
    • Korean Journal of Agricultural Science
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    • v.39 no.1
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    • pp.87-95
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    • 2012
  • Land surface temperature (LST) is an important factor in human health, thermal environment, heat balance, global change studies, and as control for climate change. The objective of this study was to assess the influence of Urban Heat Island (UHI) Effects on the LST and NDVI in Cheongju, Korea. The aim was to evaluate the effect of urban thermal environment for LST comparison of satellite-derived and in situ measured temperature. In this study, LANDSAT TM and KOMPSAT scene were used. The results indicated that the minimum LST is observed over dense forest as about $21{\sim}25^{\circ}C$ and maximum LST is observed over industrial area of about $28{\sim}32^{\circ}C$. The estimated LST showed that industrial area, bare soils and built-up areas exhibit higher surface temperatures, while forest, water bodies, agricultural croplands, and dense vegetations have lower surface temperatures during the summer daytime. Result corroborates the fact that LST over land use/land cover (LULC) types are greatly influenced by the amount of vegetation and water bodies present. The LST of industrial area and urban center is higher than that of suburban area, so it is clearly proved that there are obvious UHIE in Cheongju.

Comparison of Photosynthesis between Treatment and Non-treatment of Lime Bordeaux Mixture in 3 Year Old Root in Panax ginseng C. A. Meyer

  • Ahn, Deok-Jong;Jung, Won-Kwon;Choi, Jin-Kook;Jang, Myeong-Hwan;Kwon, Tae-Ryong;Shin, Yeon-Hwa;Lee, Sang-Chul
    • Korean Journal of Plant Resources
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    • v.26 no.3
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    • pp.370-373
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    • 2013
  • Korean ginseng has been used for thousands of years as an important medicinal plant. Lime-Bordeaux mixture (LBM) was made with copper sulfate and quicklime, which was sprayed instead of pesticides in ginseng field. Net photosynthesis ($P_N$) was compared between Treatment and Non-treatment of LBM in 3 Year Old Ginseng. $P_N$ in control plot recorded $2.94{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$ at the first day of experiment, which was similar until the last day of experiment. However, The $P_N$ in LBM recorded $2.23{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$, which was lower than that in control plot. As time goes by, The $P_N$ in LBM was gradually increased up to $3.21{\mu}mol\;(CO_2)\;m^{-2}s^{-1}$ and finally, it was similar with that in control plot at 7th day as a $3.20{\mu}mol\;(CO_2)\;m^{-2}s^{-1})$.

Spectral Reflectance Characteristics for Five Soils at Chungbuk Prefecture and Tideland Soil Using Remote Sensing Technology (원격탐사(RS) 기법을 이용한 충북지역 5개 토양과 갯벌토양의 분광반사특성)

  • Park, Jong-Hwa;Shin, Yong-Hee;Lee, Sang-Hyuk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.1
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    • pp.34-40
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    • 2003
  • The deterioration of agricultural environment, which is characterized by dryness and desertification of land, is one of the main reasons which explain the recent decrease of land productivity. To solve these environmental problems, it is very important to make clear the mechanism between soil, water, vegetation and temperature. The main objective of this study is to provide a soil surface information, which represent a soil reflectance spectrum, by remote sensing technology. The soil reflectance of the soil was measured using a spectro-radiometer in the wavelength range from 300nm to 1100nm. The results suggest that the reflectance properties of soils are related to their mineral composition and soil moisture. Increasing soil moisture resulted in an decrease in the rate of reflectance which leads to parallel curves of soil reflectance spectra.

An adaptive controller with fuzzy compensator for nonlinear time-varying systems (비선형 시변 시스템을 위한 퍼지 보상기를 가진 적응 제어기)

  • Park, Geo-Dong;Jeon, Wan-Su;Kim, Jong-Hwa;Lee, Man-Hyeong
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.2
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    • pp.149-155
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    • 1997
  • 본 논문에서는 비선형 시변 시스템을 제어할 경우 제어시스템의 안정성을 보장하고 성능을 향상시키기 위한 새로운 적응제어 구조를 전개하였다. 주어진 플랜트가 선형 시불변이라는 가정하에 표준 기준 모델 적응제어기가 적용될 경우 발생되는 출력오차는 플랜트의 비선형 시변특성으로 인하여 점근적으로 0에 수렴되지 않는다. 이때 미지의 출력오차를 점근적으로 0에 수렴시키는 방법으로 퍼지보상기를 사용하였으며 결과적으로 플랜트의 비선형 시변 특성을 보상하는 효과를 얻을 수 있었다. 퍼지 보상기로는 출력오차등의 조건에 따라 이득이 변하는 퍼지 PID 보상기를 도입하여 안정하게 설계되도록 노력하였다. 또한 출력오차를 점근적으로 0에 수렴시키는 것은 표준 기준 모델 적응제어기 내부의 모든 파라미터와 신호가 유한하게 됨을 의미하기 때문에, 제어시스템 전체의 안정도를 보장할 뿐만 아니라 결과적으로 과도응답 성능을 향상시킬 수 있게 되었다. 몇가지 예제를 대상으로 시뮬레이션을 수행하고 그 결과를 분석함으로써 비선형 시변 시스템을 제어할 경우 본 논문에서 전개된 새로운 적응제어 구조의 타당성을 확인하였다.

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Forkhead Genes are Key Regulators of Developmental Processes in Aspergillus nidulans

  • Oh, Dong-Soon;Kim, Jong-Hwa;Han, Dong-Min;Han, Kap-Hoon
    • 한국균학회소식:학술대회논문집
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    • 2014.05a
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    • pp.39-39
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    • 2014
  • In a homothallic filamentous fungus Aspergillus nidulans, sexual and asexual developments are largely affected by the genetic and environmental factors. To regulate the complex subsets of genes involved in the developmental processes accurately, tight regulations of transcription factors are required. The forkhead type transcription factors are the class of regulators that function in a broad spectrum of cellular and developmental processes in many species from yeast to human. Here, we identified the fkhA and fkhB genes that encode a conserved forkhead transcription factors. The fkhA deletion resulted in the complete loss of fruiting body formation under all conditions favoring sexual development, suggesting that the fkhA gene is required for sexual development in A. nidulans. Overexpression of fkhA resulted in enhanced formation of fruiting bodies under induction condition not only in the normal condition but also in the condition of presence of 0.6 M KCl, which strongly inhibits sexual development. To know the function of the fkhB gene, we also generated fkhB knock-out strain in A. nidulans. Deletion of fkhB resulted in abnormal conidiophore formation under standard conditions and delayed sexual development process, suggesting that the fkhB gene plays an important role in conidiophore morphogenesis Taken together, these results suggest that the fkhA gene is necessary and sufficient for regulating sexual development and the fkhB gene is a transcription factor related in asexual developmental process in A. nidulans.

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Direct Detection of Escherichia coli, Staphylococcus aureus, and Salmonella spp. in Animal-derived Foods Using a Magnetic Bead-based Immunoassay

  • Kim, Jong-Hui;Yoo, Jae Gyu;Ham, Jun-Sang;Oh, Mi-Hwa
    • Food Science of Animal Resources
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    • v.38 no.4
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    • pp.727-736
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    • 2018
  • In this study, an immuno-magnetic bead (IMB)-based assay was developed to simultaneously detect Escherichia coli, Staphylococcus aureus, and Salmonella spp. and was tested in four animal-derived foods: beef, ham, egg, and ricotta cheese. The IMB-based assay exhibited good specificity by binding to five E. coli serotypes [capture efficiency (CE) average (avg.) 90.4%], five S. aureus strains (CE avg. 91.4%), and five Salmonella serotypes (CE avg. 95.4%) but not binding to non-target bacteria (CE<10%). Furthermore, the assay detected all three pathogens with a detection limit of 10 CFU/g without the need for enrichment or additional platforms. Since the results demonstrated that the IMB-based assay can effectively separate and enrich target bacteria from a variety of animal-derived food matrixes, the assay exhibits good specificity for potential use in providing rapid, immunological, presumptive identification of pathogenic bacteria.

High-Speed Dynamic Decimal Adder Design (고속 다이나믹 십진 가산기 설계)

  • You, Young-Gap;Kim, Yong-Dae;Choi, Jong-Hwa
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.6 s.312
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    • pp.10-16
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    • 2006
  • This paper proposed a carry lookahead (CLA) circuitry design. It was based on dynamic circuit aiming at delay reduction in an addition of BCD coded decimal numbers. The performance of these decimal adders is analyzed demonstrating their speed improvement. Timing simulation on the proposed decimal addition circuit employing $0.18{\mu}m$ CMOS technology yielded the worst-case delay of 0.83 ns at 16-digit. The proposed scheme showed a speed improvement compared to several schemes for decimal addition.

A Preprocessor for English-to-Korean Machine Translation of Web Pages (웹용 영한 기계번역을 위한 문서 전처리기의 설계 및 구현)

  • An, Dong-Un;Ryu, Hong-Jin;Seo, Jin-Won;Lee, Young-Woo;Jeong, Sung-Jong;Yuh, Sang-Hwa;Kim, Tae-Wan;Park, Dong-In
    • Annual Conference on Human and Language Technology
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    • 1997.10a
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    • pp.249-254
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    • 1997
  • 영어 웹 문서를 한국어로 기계번역을 하기 위해서는 HTML 태그를 번역 대상 문장과 분리하는 처리가 필요하다. HTML 태그를 단순히 제거하는 것이 아니라 대상 문장의 기계번역이 종료된 후에 같은 형태의 한국어 웹 문서로 복원하기 위한 방안이 마련 되어야 한다. 또한 문서 전처리기에서는 영어 형태소해석기의 성능을 높이기 위하여 번역 단위가 되는 문장의 인식 및 분리, 타이틀의 처리, 나열된 단어의 처리, 하이픈 처리, 고유명사 인식, 특수 문자 처리, 대소문자 정규화, 날짜 인식 등을 처리하여 문서의 정규화를 수행한다.

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