• Title/Summary/Keyword: Cho, Hyun Myung

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A Basic Study on the Effects of Shrinkage.reducing Agent on the Autogenous Shrinkage of Super.high.strength Concrete (수축저감제가 초고강도콘크리트의 자기수축에 미치는 영향에 관한 기초적 연구)

  • Park, Hyun;Choi, Myung-Hwa;Kim, Hak-Young;Cho, Seung-Ho;Kim, Woo-Jae;Jung, Sang-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.401-402
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    • 2009
  • This study prepared super high strength concrete, in which the water.binder ratio is very low, through experimental mixture, and conducted basic research on how super high strength concrete is affected by shrinkage reducing agent that is utilized to inhibit the shrinkage of concrete.

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A SIMPLE AND QUANTITATIVE DETERMINATION OF PU ISOTOPES IN SOIL SAMPLES

  • Lee, Myung-Ho;Choi, Geun-Sik;Chung, Kun-Ho;Cho, Young-Hyun;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.191-195
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    • 2001
  • An accurate and simple analytical technique for low levels of fallout Pu in the environment was developed using an anion exchange resin. To develop the reliable determination of Pu isotopes in soil samples, decomposition of soil matrix, plutonium oxidation state adjustment on the anion exchange column and source preparation of Pu isotopes have been carried out. The optimum method of Pu isotopes with an anion exchange has been validated by application to IAEA-Reference soils.

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Pediatric Acute Kidney Injury: Focusing on Diagnosis and Management

  • Cho, Myung Hyun
    • Childhood Kidney Diseases
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    • v.24 no.1
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    • pp.19-26
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    • 2020
  • Acute kidney injury (AKI) is common in critically ill children, and is associated with increased mortality and long-term renal sequelae. The definition of pediatric AKI was standardized based on elevation in serum creatinine levels or decrease in urine output; accordingly, epidemiological studies have ensued. Although new biomarkers appear to detect AKI earlier and predict prognosis more accurately than traditional markers, they are not frequently used in clinical setting. There is no validated pharmacological intervention for AKI, so prevention and early detection are the mainstays of treatment. For high risk or early stage AKI patients, optimization of volume status and blood pressure, avoidance of nephrotoxins, and sufficient nutritional support are necessary, and have been demonstrated to be effective in preventing the occurrence of AKI and improving prognosis. Nevertheless, renal replacement therapy is needed when conservative care fails.

Acylucosyl Sterols from the Roots of Caragana chamlagu (골담초근의 Lipid성분에 관한 연구)

  • Cho, Young-Kyung;Lee, Myung-Whan;Kang, Hyun-Mo;Lee, Han-Koo;Kang, Sam-Sik
    • Korean Journal of Pharmacognosy
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    • v.23 no.1
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    • pp.14-19
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    • 1992
  • A mixture of acylglucosyl sterols together with ${\beta}-sitosterol$, ${\beta}-sitosterol\;3{\beta}-O-glucoside$ and fatty acids was isolated from the roots of Caragana chamlagu as their acetate forms and the structure elucidated by chemical and spectroscopic means. The major acylglucosyl sterol was ${\beta}-sitosteryl\;3-O-[6'-O-oleoyl]-{\beta}-D-glucopyranoside$ while the minor components were $6'-O-palmitoyl-\;and\;6'-O-stearoyl-{\beta}-D-glucosyl$ sitosterol congeners. The isolation and structure elucidation of these acylglucosyl sterols are reported for the first time from the genus Caragana.

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Comparisons of Performance with Heat Exchanger Constitution in the Fin-tube Gascooler (핀-관 가스쿨러에서 열교환기 구성에 따른 성능 비교)

  • Bae, Kyung-Jin;Shin, Eun-Sung;Hong, Myung-Suk;Cho, Hong-Hyun
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1294-1299
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    • 2009
  • Since the operating pressure of $CO_2$ gascooler is so high compared with that of previous subcritical condenser, the optimization of gascooler is needed for improve heat exchanger performance. In this study, the performance characteristics of five kinds of heat exchangers were analyzed and compared with operating conditions. As a result, the 4-20 HX-tube shows the maximum gascooler capacity because the heat transfer is effective and pressure drop is small. Beside, the high performance of 4-20 HX-tube could be keep for wide operating condition.

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Nuclear Design Methodology of Fission Moly Target for Research Reactor

  • Cho, Dong-Keun;Kim, Myung-Hyun;Sohn, Dong-Seong
    • Nuclear Engineering and Technology
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    • v.31 no.4
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    • pp.365-374
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    • 1999
  • A nuclear design of fission moly production targets for a research reactor, HANARO was peformed. It was found that the use of MCNP-4A, ORIGEN-2 code was reliable for the analysis of production characteristics of $^{99}$ Mo in a target fuel at an irradiation holes. A parametric study was done for the optimization of target location, target dimension, target shape and fuel materials. It was shown that a fuel thickness was the most sensitive parameters and electro-deposited target gave the highest 99Mo yield ratio. A pellet target with vibro-compaction powder, however, showed the largest production capacity and better engineering feasibility even with less yield ratio. Ten kinds of optimized target design for both LEU and HEU satisfied all the given design constraints. The most favorable design was the HEU ring-shaped electro-deposited target, considered the safety limit, production yield, chemical process easiness, yield ratio, and amount of radioactive waste.

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A Study on New Village Planning in the Farming Zone of Saemangeum Reclaimed Area (새만금간척지 신농촌마을 계획수립연구)

  • Shim, Hwan-Hwi;Choi, Soo-Myung;Cho, Joong-Hyun
    • Journal of Korean Society of Rural Planning
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    • v.17 no.4
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    • pp.61-74
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    • 2011
  • Based on the critical review of previous new village planning proposals in Saemangeum Farming Zone, this study tried to derive rational and realistic planning/design criteria for new villages firstly through home-and-abroad case studies analysis, interview works on farmers in two villages located in the existing reclaimed farming areas and influential zone analysis from neighborhood villages in old land. By applying these criteria(population structure, farming size, maximum distance between farmland and home, village site size, number of new villages planned) on Saemangeum Farming Zone, basic new village planning framework was proposed finally.

13 Weeks Repeated-Dose Toxicity Studies 1,3-dichloro-2-propanol in Rats

  • Oh, Jae-Ho;Shin, Dong-Hwan;Kim, Sheen-Hee;Hwang, Myung-Sil;Lim, Chul-Joo;Yum, Young-Na;Yang, Ki-Hwa;Cho, Dae-Hyun
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.05a
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    • pp.54-54
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    • 2003
  • 1,3-Dichloro-2-propanol(1,3-DCP), together with 3-monochloro-propane -1,2-diol(3-MCPD), is a well-known contaminant of acid-hydrolysed vegetable protein. 1,3-DCP has also been found to occur in a range of other foods and ingredients, most notable in soy sauce. The objective of the study was to determine the toxicity of the 1,3-DCP in the rat following oral administration for 13 weeks. (omitted)

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Arsenite-induced Hepatotoxicity in Chang Liver and Clone 9 Cells

  • Yum, Young-Na;Ahn, Jin-Hong;Kim, Gi-Dae;Hwang, Myung-Sil;Kim, Sheen-Hee;Lim, Chul-Joo;Yang, Ki-Hwa;Kim, Dae-Kyung;Cho, Dae-Hyun
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.05a
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    • pp.56-56
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    • 2003
  • The reactivity and toxicity of arsenic compounds depend on the their oxidative states. Exposure to arsenic causes many human health effects, including cardiovascular, hepatic and renal disease, in addition to cancer in kidney, liver, lung, urinary bladder and skin. The cytotoxic effects of arsenite on normal hepatocyte, which most of its biotranfomation takes place. (omitted)

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Toxicological studies on arsenic by in vitro alternative method

  • Yum, Young-Na;Ahn, Jin-Hong;Oh, Jae-Ho;Hwang, Myung-Sil;Kim, Sheen-Hee;Yang, Ki-Hwa;Cho, Dae-Hyun
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.05a
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    • pp.57-57
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    • 2003
  • Epidemiological studies of arsenic have shown that chronic exposure to arsenic can result in an increased incidence of cancer of the lung, skin, bladder and liver. It is impossible that the toxicity study of arsenic in the human, we become to measure in vitro cytotoxicity of inorganic and organic arsenic in the human normal liver cells including Chang Liver and WRL. (omitted)

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