• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.57-61
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• 1983

The present study was undertaken to elucidate the effect of Serotonin and Norepinephrine on Aldehyde Oxidase activity in rabbit liver, in vitro. The results were as follows; 1. Aldehyde Oxidase was measured optimum substrate concentration at $5{\times}10^{-4}M$ and incubation time for 10 minutes. 2. Aldehyde Oxidase were inhibited by Serotonin and Norepinephrine. 3. It was observed that relationship between biogenic amines and substrate were competitive inhibition on Aldehyde Oxidase.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.435-444
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• 2023

Suitable environmental conditions in Saemangeum frequently favor phytoplankton growth. There have been occurrences of sudden phytoplankton blooms, surpassing the algae management standards. A model was designed to prevent such blooms using scientific predictive techniques to forecast and regulate the possibility of phytoplankton blooms. We propose effective and efficient algae control measures concerning every phytoplankton species optimized through the policy control of nutrients (DIN, PO4-P) from rivers and controlling lake salinity using gate operations. The probability of phytoplankton blooms was initially forecast using an artificial neural network algorithm based on observations. The model's Kappa number fluctuated from 0.7889 to 1.0000, indicating good to excellent predictive power. The Garson algorithm was then utilized to assess the significance of explanatory variables for every species. Meanwhile, the probability of phytoplankton blooms was anticipated depending on the DIN and salinity value changes. Therefore, the model predicted the precise DIN and salinity concentrations to inhibit phytoplankton blooms for each species. Hence, the green algae model can create effective proactive measures to avoid future phytoplankton blooms in enormous artificial lakes.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.108-108
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• 1998

일반적으로 탄소강은 수용액 중에 노출될 경우 전면부식에 의한 손상을 받는다. 그러나 부식방지를 위하여 부식억제제를 적용할 경우, 탄소강의 부식거동은 현저한 변화를 겪게된다. 이러한 부식거동의 변화는 첨가되는 부식억제제의 종류에 따라 분 류할 수가 있는데, 양극부식억제제, 음극부식억제제 그리고 이들의 혼합부식억제제로 분류할 수가 있다. 현장에 적용된 부식억제제 시스템 중에는 자동차용 부동액과 가스히터용 열전달 매체액이 있다. 이러한 부식억제제가 적용된 시스댐은 정확한 부식억제능의 평가에 의한 그 교체 시기의 결정이 매우 중요하다. 교체 시기가 빠를 경우, 유지비용이 과다하게 소요되는 문제가 있으며, 교체시기가 늦을 경우 설비의 부식을 초래하는 문제 가 있다. 따라서 부식억제제의 정확한 성능 평가법은 매우 중요하며, 이에 대한 다양 한 연구가 진행 중이다. 부식억제제가 함유된 용액의 부식억제성능을 평가하는 방법에는 대표적으로 무게 감량법을 이용하고 있다. 이 방법은 다종의 금속이 적용된 자동차용 부동액을 실제 사용조건과 유사한 실험 조건에서 단기간, 가혹조건에서의 무게 감량에 의해 부식억 제능을 평가하는 방법이다. 그러나 이러한 방법은 특히 국부부식이 진행될 경우 부 식억제능을 정량화 하는데 어려움이 있다. 한편 전기화학적 측정방법으로는 분극곡선법을 이용한 $E_P$(공식개시전위), $E_R$(재부동태 화전위)의 측정법이 있다. 또한 부식억제피막의 안정성을 측정하기 위한 방법으로 인 위적인 양극전류 인가에 의한 피막의 파괴후에 피막이 복원가능 여부 및 그 속도 측 정에 의해 부식억제제의 건전성을 확인할 수가 었다. 본 연구에서는 가스히터의 주구성 재료인 A210 Gr Al의 탄소강을 사용하여, 사용기간이 5년 이상되어 부식억제 기능을 거의 상실한 것으로 여겨지는 열전달 매체액 과 신규 부식억제제가 적용된 시스템 등 객관적으로 확인된 부식억제제 시스랩에 대 하여 다양한 평가 방법을 동원 비교분석하고자 하였다. 실험은 KSM 2142에 의한 무게감량법, 분극곡선 측정에 의한 $E_P$(공식개시전위), $E_R$(재부동태화전위) 측정, 시간에 따른 자연전위 변화 측정 빛 이때의 부식속도(선형분극법), 인위적인 피막 파괴 전,후 의 전위 변화 및 부식속도 측정법에 의한 국부부식 발달 저지능 등을 평가하여 각 실험결과를 비교분석하여 보았다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.05a
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• pp.431-434
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• 2006

폴리머 라텍스의 탄화와 메탄-질소 혼합가스의 CVD법으로 Carbon whisker를 가진 활성탄막을 개발하였다. 이 막의 PMMA 현탁물질 여과실험과 실제의 현탁물질과 용존유기물을 함유한 오래된 수도관으로부터 얻어진 적수여과실험 결과, Carbon whisker의 유무가 fouling에 의한 막의 flux를 억제하는 것으로 밝혀져, 실제의 정수공정에의 응용 가능성을 보였다.

• 대한핵의학회:학술대회논문집
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• 1967.11a
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• pp.101.3-101.3
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• 1967

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.29 no.10
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• pp.28-34
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• 2000

차량용 에어컨의 증발기 표면에 공기가 지나갈 때 결로로 인한 통풍저항 증대와 비산 현상을 억제하며 세균번식과 냄새가 발생하는 증발기에 항균성과 탈취효과를 주기 위해, 친수-항균재가 세계적으로 1980년대부터 적용되어 왔다. 본 고에서는 친수-항균재의 기술개발 동향과 평가기술을 소개하고자 한다.

• Strategy21
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• s.34
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• pp.236-261
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• 2014

The future role of nuclear extended deterrence in the security alliance between the United States and the Republic of Korea is currently a central concern. The gradually lessening role of reliance on nuclear weapons in US security policies broadly, combined with increasing North Korean nuclear capabilities and belligerence, raise fresh questions about the sufficiency of the "nuclear umbrella" as a pillar of the US-ROK defense posture. This article addresses the current and future role of nuclear extended deterrence in Korea in this dynamic context. The article reviews the longstanding trend toward reducing the overall size of the US nuclear arsenal, and assesses developments in US-ROK outlooks toward extended deterrence in response to the Obama administration's nuclear policies and North Korea's recent smaller-scale aggressions. The analysis finds that the challenges of deterrence credibility and allied reassurance are difficult and long-term. The analysis explains how these challenges emerge less from a shrinking US numerical arsenal size than from the sufficiency of specific nuclear and non-nuclear capabilities to meet emerging smaller-scale threats. The analysis also highlights the importance of broader strategic and political interaction in sustaining allied confidence in any joint security posture. The evaluation concludes that a strong US-ROK alliance relationship can be maintained while the size of the US nuclear arsenal continues to decline, in part because nuclear weapons in any deployment configuration are relatively ineffective means for deterring smaller-scale aggression. Nevertheless, continuing adjustment of the US-ROK extended deterrence posture to the evolving, complex and uncertain Korean peninsula security environment will remain an ongoing challenge. Finally, the article encourages further examination of the potential specific role ROK maritime forces might serve in enhancing deterrence of smaller-scale threats while minimizing risks of conflict escalation.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.4
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• pp.48-56
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• 2011

A Possibility of combustion instability on longitudinal mode has a high level at large scale of L/D. Solid propellant has a metal particle and a grain of control to pressure oscillation. Solid rocket motor in slotted-tube grain controls pressure oscillation of longitudinal mode. Slotted-tube grain restrains longitudinal 1st pressure oscillation. But cavity volume of aft. insulation ablation amplifies 2nd pressure o scillation by vortext shedding. A study has suppressed combustion instability and vortex shedding by modified 4 slotted tube solid rocket motor design.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.825-828
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• 2003

This study was performed to determine the antimicrobial activity of waste food fractions, the Solanum tuberosum Peel (SP) and Allium cepa L. Peel (AP) on several microorganisms. The methanol extracts (SPM, APM) of SP and AP were fractionated to five different types, which were hexane, ethylether, ethylacetate, butanol and water Among the various fractions, ethylether and butanol fractions of AP (APMEE, APMB) showed stronger antimicrobial activity against Pseudomonas aeruginosa and Staphylococcus aureus than the other fractions. The ethylether fraction of SP (SPMEE) also showed the higher antimicrobial activity against Escherchia coli than the other 4 fractions . These results suggest that the waste food fractions, SP and AP may be developed into bioactive antimicrobial health products.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.205-209
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• 1977

The pool size of plasma glucose, turnover rate and other concerned items for glucose metabolism in normal laying hen were investigated by a single-injection method using $U-C^{14}-glucose$. The 11.6 nCi of pure dose was injected to a hen normally fed through the wing vein. The glucose concentration in plasma sample taken at 5 minutes after injections was 214mgper 100ml. From the plottings of logarithmic standard specific activities of plasma taken from 5 to 120 minutes against the time after injection and from the regresion analysis, metabolic states were determined. The pool size was 1.07g, turnover rate was 0.024 per minute, turnover time was 41 minutes, utilization rate was 26mg/min. (0.83 g/hr/kg B.W. 3/4) and glucose space(extracellular fluid volume) was 25.3 per cent of body weight. The values obtained from. 10-50 minutes samples were similar to those described above, which we from 5-120 minutes samples.