• Title/Summary/Keyword: 동화현상

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Characteristics of Geochemical Processes along the Salinity Gradient in the Han River Estuary (한강 기수역에서 염분구배에 따른 지화학적 특성 변화)

  • 김동화;박용철;이효진;손주원
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.9 no.4
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    • pp.196-203
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    • 2004
  • To understand the geochemical processes in the Han River Estuary, distributions and behaviors of nutrients, dissolved organic matters, and uranium were investigated and analyzed during estuarine tidal mixing in June 2000 and February 2001. The distribution of inorganic nutrients showed very dynamic distributional patterns implying an apparent nitrification process and a concave non-conservative mixing along the salinity gradient. Dissolved organic carbon was high in the upstream region and decreased sharply in the low salinity region of around 5 psu. The 3-D fluorescence characteristic of dissolved organic matter showed two distinct fluorophores in the study area. Biomacromolecules originated mainly from the indigenous biochemical processes and geomacromolecules from terrestrial humic materials. In the study area, the distribution of geomacromolecule showed a concave non-conservative property along the salinity gradient presumably due to the flocculation and removal processes in the estuary. Meanwhile, distribution of the dissolved uranium, mainly in the form of stable uranium carbonate complex, also showed a concave non-conservative property along the salinity gradient in the Han River Estuary. From this study, the removal rate of dissolved uranium in the Han River Estuary was estimated to be about 7.1 ton per year.

Monitoring of Microbial Contaminants in Processing Line of Some Mushromm Canneries (양송이 통조림 공장의 미생물 오염도 변화 추적)

  • 신동화;홍재식
    • Journal of Food Hygiene and Safety
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    • v.4 no.2
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    • pp.103-108
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    • 1989
  • Three mushroom cannerries were selected by size which are representative vegetable processing firms in korea for monitoring microbial contamination of processing water, washing water, mushroom before and after washing through first and second washing tanks and, blanched and prolonged mushroom for certain time at room temperature. Total contamination degree was expressed as colony forming unit (CFU) of mesophilic aerobes. The contamination degree of processing water was $10^{2}\;CFU/100\;ml$ and washing water in first and second washing tank were 10 to 100 times higher than processing water. When 2.3 tons of washing water was used for washing 1 ton of mushroom, washing effect was showed by reduction of microbial load but cutting it to 1.8 tonsIl ton of mushroom, microbial load was higher than that of raw mushroom level. Blanching reduced microbial load to 50-500 CFU/g of blanched mushroom and it was not seen much increase of CFU in blanched mushroom left at room temperature for 3 hours in $16^{\circ}C$ processing water. Just after injection of $80^{\circ}C$ brine in container, CFU/ml of brine in container was $84{\times}10^{4}$ but it was increased rapidly to $20{\times}10^{7}$ after 2 hours at ambient temperature.

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Towards Intercultural Christian Education: A Christian Educational Response to Multicultural Phenomenon in the South Korean Context (상호문화적 기독교교육: 한국의 다문화현상에 대한 기독교교육적 응답)

  • Choi, Heejin
    • Journal of Christian Education in Korea
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    • v.61
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    • pp.263-294
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    • 2020
  • In South Korea which has become a multicultural society, ethnic and cultural others have suffered from discrimination against them and isolation from society. Multicultural policies and multicultural public education have simply focused on the assimilation of cultural others without providing opportunities to build a reciprocal relationship between Kor eans and cultural others. Noting this reality, this paper proposes intercultural Christian education as a prophetic and educational role of faith communities in society. Intercultural education, intercultural theology, Miroslav Volf's drama of embrace, and Sang-Jin Park's theory of the ecosystem of Christian education offer theoretical foundations for intercultural Christian education. Based on these foundations, the paper discusses the definition and goal of intercultural Christian education and argues for the roles of intercultural Christian education to help Christ ians "SEE" the self, the other, and the community through self-reflection, embrace, and ecological transformation. As intercultural Christian education pursues to nurture Christians to have a respectful and hospitable mindset toward cultural others, such education will help faith communities seek a multi-colored kingdom of God.

Measurement of Biogenic Amines with a Chitopearl Enzyme Reactor (Chitopearl 효소 Reactor를 이용한 Biogenic Amines 측정)

  • Park, In-Seon;Kim, Dong-Kyung;Shon, Dong-Hwa;Cho, Yong-Jin;Kim, Nam-Soo
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.593-599
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    • 1999
  • Substrate specificity of a flow-injection-analysis (FIA)-type biogenic amine sensor with enzyme reactor was determined. The enzyme reactor was prepared with a diamine oxidase immobilized on preactivated chitosan porous beads (Chitopearl) by intramolecular cross-linking via glutaraldehyde. The sensor showed a rapid response to putrescine and a quasi-linear calibration curve was obtained up to 15.0 mM. The optimal pH and temperature of the enzyme reactor system were 7.5 and $35^{\circ}C$. Interferences due to ATP-related compounds and trimethylamine, and the effects of NaCl and amino acids were measured. Inhibitory effects owing to these components could be mitigated by sample extraction with perchloric acid. Polyamines except putrescine were determined by a putrescine calibration range within 26.7%. This system was confirmed as rapid and convenient for biogenic amine determination.

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Antimicrobial Effect of Some Plant Extracts and Their Fractionates for Food Spoilage Microorganisms (식품 부패미생물에 대한 천연 항균성물질의 농도별 및 분획별 항균 특성)

  • Lee, Byung-Wan;Shin, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.23 no.2
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    • pp.205-211
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    • 1991
  • Ethanol extracts of amur cork, elm root, plantain and dandelion which are edible and can be mass produced at farm were examined their inhibitory activity against food spoilage microorganisms at their concentrations and the extracts were fractionated by some solvents with checking effective fractionate. Above $500{\sim}2000\;ppm$ of the extracts inhibited completely the test microorganisms with a few exception. One thousand ppm of amur cork exract inhibited B. cereus completely. L. mesenteroides by 500 ppm of amur cork and 2000 ppm of elm root and plantain showed a pretty good inhibition. The extracts which showed good inhibition to the test microorganisms were fractionated with chroloform, ethylacetate, butanol and water in order and the fractionates of butanol and chroloform showed comparetively higher inhibition than others generally. Inhibition rate of each fractionate were as follows ; B. cereus was inhibited completely at 500 ppm of chroloform fraction, and 1000 ppm of ethyl acetate and butanol and L. mesenteroides was 500 ppm of butanol fraction. P. fluorescens was inhibited partly by 500 ppm of butanol and ethyl acetate fraction.

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Effects of Reading Motivational and Behavioral Factors on the Population of High, Middle and Low Scores in Science Achievements of PISA 2009 (PISA 2009 과학성취도 상중하 집단별 읽기태도 및 읽기방법의 영향)

  • Kim, Dong-Hwa;Seo, Hae-Ae;Kim, Mijung
    • Journal of The Korean Association For Science Education
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    • v.33 no.2
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    • pp.538-551
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    • 2013
  • Korea is reported as one of the highest performing OECD countries in PISA 2009 science achievement, ranking $4^{th}{\sim}7^{th}$ among 65 participating countries. However, the top level 6 percentage came only at 1.1% and ranks $18^{th}$ among paticipating countries. Such dissatisfying results call for attention to seek effective teaching and learning strategies for top level students in Korea. This study aims to investigate the effect of reading motivational and behavioral factors on PISA 2009 science achievement for the population who scored high compared to populations scoring middle and low. For this purpose, PISA 2009 science achievement as well as students questionnaire data were utilized. Variables of reading motivational and behavioral factors were selected and structural equation modeling was employed to examine a hypothetical cause-effect relationship between reading factors and science achievement. It was found that there is a cause-effect relationship between reading factors and science achievement for the whole population. For those in the top 16% of students in PISA 2009 science achievement, reading behaviors on text-memorization have had little or no effects, while reading motivational and other behavioral factors showed a significant influence. In contrast, the middle 68% and low 16% populations have had significant effects for text-memorization on science achievement.

Synergistic Effect of Rhus javanica Linne Ethanol Extract Containing Several Synergist (항산화 효과가 있는 붉나무 추출물의 몇가지 synergist 첨가 효과)

  • Chang, Young-Sang;Choi, Ung;Shin, Dong-Hwa;Shin, Jae-Ik
    • Korean Journal of Food Science and Technology
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    • v.24 no.2
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    • pp.149-153
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    • 1992
  • Antioxidative effects of crude ethanol extract of the Rhus javanica L. and its fractionates with various synergists on the oxidation of palm oil, lard and soybean oil were compared with induction period(IP) using a Rancimat test. Addition of 200 ppm of the crude extract with phosphoric acid to palm oil extended IP 2.89 times as much as that of control and ethyl acetate fractionate extended IP 4.18 times at the same condition. To lard, 600 ppm of chloroform fraction with 200 ppm of ${\delta}-Tocopherol$ extended IP 13.42 times as much as that of control. 200 ppm of each fraction with various synergists were added to palm oil and lard, and oxidative stability of the oils were monitored by measuring POV, AV, and TBA value. The POV of palm oil containing 200 ppm of ethyl acetate and chloroform fraction with 200 ppm of phosphoric acid after 27 days storage at $60^{\circ}C$ were 8.9 meq/kg and 9.4 meq/kg respectively while the POV of control was 98.3 meq/kg at the same condition. AV and TBA value were also lower than that of control. The POV value of lard containing same amount of ethyl acetate and chloroform fraction with ${\delta}-Tocopherol$ after 12 day storage at $60^{\circ}C$ were 20.0meq/kg and 10.7 meq/kg respectively while the POV of control was 161.1 meq/kg at the same condition. AV and TBA value were also lower than that of control.

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EFFECT OF QUINONES ON $NADPH_2$ OXIDATION AND PHOTOSYNTHETIC $CO_2$ ASSIMILATION IN CHLORELLA PYRENOIDOSA (Chlorella Pyrenoidosa에 있어서 $NADPH_2$의 산화(酸化)와 광합성(光合性)에 의(依)한 $CO_2$ 동화작용(同化作用)에 대(對)한 Quinone의 영향(影響))

  • Cho, Duck-Hiyon
    • Applied Biological Chemistry
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    • v.11
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    • pp.29-33
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    • 1969
  • 1. The oxidizability of $NADPH_2$ by quinones in the presence of $NADPH_2$-diaphorase was tested under aerobic conditions. Also the $^{14}CO_2$-fixation rates were compared when Chlorella suspensions were pretreated with $3{\cdot}10^{-5}M$ cocentration of variou quinones for 10 minutes prior and during the $^{14}CO_2$-fixation period. 2. A close correlation seems to exist between the rate of $NADPH_2$ oxidation by quinones and the $^{14}CO_2$-fixation rate. The effect of quinones on $NADPH_2$ oxidation and $^{14}CO_2$-fixation were in the order of Dichlone>06-K>NQ>BQ. 3. It is postulated that the phytotoxicity of quinones on Chlorella is due to the deprival of $NADPH_2$ consequently inhibiting $^{14}CO_2$-fixation, thus causing death of the cells. 4. The effect of quinones on amino acids biosyn-thesis in Chlorella was one of depressed rates, which was especially noted in the case of dichlone. This would be expected from a consideration of $NADPH_2$ deprival and inhibition of $^{14}CO_2$-fixation. Sucrose synthesis was either not affected or rather stimulated, the reasons of which are not clear at the present time.

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Korean Diaspora: From Overseas Compatriots to Network (코리안 디아스포라: 공동체에서 네트워크로)

  • Chung, Sung-Ho
    • Korea journal of population studies
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    • v.31 no.3
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    • pp.107-130
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    • 2008
  • The study of Korean diaspora has focused on migration, adaptation, and identity of overseas Koreans in China, the CIS, Japan, and the United States. However, the contemporary concept of a diaspora is a way of understanding migration, cultural difference, identity politics, and so on. Thus, this more broadly defined diaspora is used to mean a dispersion of people of a common national origin or of common beliefs living in exile. As of 2007, it is estimated that there are about 7 million Koreans living in 170 countries outside the Korean peninsula. Some have left Korea involuntarily and some others voluntarily. But most of them actively try to maintain their identity and culture as Koreans. With the large number of overseas Koreans, there has recently been the recognition of the importance of networking among overseas Koreans in the 21st century. The purpose of this paper is to emphasize the necessity of Korean Global Network of overseas Koreans. In doing so, this paper reviewed the case of Jewish and Chinese network. Then, this paper indicates the problems in the networking of overseas Koreans and suggests the policy implications for Korean Global Network. Above all, there should be changes in the government's policy towards overseas Koreans in the direction of organizing networks of overseas Koreans to coexist with the mother country. The government should adopt a policy to restore trust in overseas Koreans. It should take a pragmatic approach to the mutual interests in the socioeconomic relations instead of taking a political approach to overseas Koreans.

Study of flood prevention alternative priorities using MCDM (Multi-Criteria Decision Making) (MCDM을 이용한 홍수방어대안 우선순위 정립에 관한 연구)

  • Lim, Donghwa;Jeong, Soonchan;Lee, Eunkyung;Yi, Jaeeung
    • Journal of Korea Water Resources Association
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    • v.50 no.3
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    • pp.169-179
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    • 2017
  • Recently, due to global warming and climate change in Korea, local heavy storm occurs frequently. In this study, the risky areas for flooding in urban areas are analyzed for flood inundation based on two-dimensional urban flood runoff model (XP-SWMM) focusing on coastal high flood-risk urban areas. In addition, the MCDM (Multi-Criteria Decision Making) technique is utilized in order to establish the flood defense structural measures. The alternative flood reduction method are compared and the optimum flood defense measures are selected. A simulation model was used with three structural flood prevention measures (drainage pipe construction, water detention, flood pumping station). In order to decrease the flooding area, flood assessment criteria are suggested (flooded area, maximum inundation depth, damaged residential area, construction cost). Priorities of alternatives are determined by using compromise programming. As a result, the optimal flood defence alternative suggested for Janghang Zone 1 is flood pumping station and for Janghang Zone 2, 3 are drainage pipe construction.