• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.41.1-41
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• 2004

본 발표에서는, 최근 고속 고정밀 이송계로 각광을 받고 있는 리니어 모터의 열특성 분석과 구동부 설계변경을 통한 첨단 이송계의 열변형 억제 및 최소화 기술에 대해 다루고 있다. 리니어 모터의 공작기계에 적용 시, 리니어 모터의 발열원과 열전달 경로 등을 분석하고 이에 대응한 냉각기법과 단열재의 배치에 따른 고성능 이송계의 열특성 개선 사례를 소개한다. 새로운 리니어 모터의 공작기계에 적용은 선택사항에서 필수사항으로 이동한다.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1389-1395
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• 2000

Cervical cancer has been one of the leading causes of female death from cancer worldwide with about 500,000 deaths per year. A strong association between certain human papillomaviruses (HPV types 16 and 18) and cervical cancer has been well known. An extract of natural products, Rhus, has been used to investigate whether this agent has the ability of inhibiting the oncogenes E6 and E7 of HPV type 16. This Rhus inhibited the proliferation of human cervical cancer cell lines (C-33A, SiHa, Caski) and HaCaT keratinocytes in a dose response manner. In vitro binding assay and ELISA showed that Rhus inhibited the in vitro binding of E6 and E6AP which are essential for the binding and degradation of the tumor suppressor p53. In addition, Rhus inhibited the in vitro binding of E7 and Rb which essential tumor suppressor for the control of cell cycle. The level of mRNA for E6 was also decreased by Rhus while that of E7 mRNA was not changed. Our data suggested that Rhus inhibited the oncogenecity of E6 and E7 of HPV 16 type, thus can be used as a putative anti-HPV agent for the treatment of cervical carcinomas by HPV.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.173-180
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• 2009

Very-early strength latex-modified concrete(below ; VES-LMC) was developed for possible early-opening-to-traffic after overlay of bridge deck concrete. The purpose of this study is to analyze the cause of map, transverse and longitudinal cracking in VES-LMC and to provide a control method for minimizing occurrence of cracking. The proposed prevention method against map and transverse cracking was verified by field data. VES cement was modified as the unit cement content was reduced from 390kg/$m^3$ to 360kg/$m^3$. The maximum size of coarse aggregate was increased from 13mm to 19mm. The wire mesh and steel fiber were adopted in concrete mixture. From the results, the proposed prevention method against map and transverse cracking was verified since structural cracking was not occurred until 3 years after overlay.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.245-252
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• 1993

To investigate a simple and rapid screening method for photosynthetic inhibitory herbicides, responses of tobacco(Nicotiana tabacum L.) and liverwort(Marchantia polymorpha L.) PA(photoautotrophic) cells to various commercial herbicides with different modes of action and leaf extracts of four weed species were compared. PET (photosynthetic electron transport) inhibitory type of herbicides has greater inhibitory effect in liverwort photoautotrophic cells than the photomixotrophic and heterotrophic cultured cells. Similary, PET inhibitory type of herbicides inhibited the oxygen evolution more in liverwort PA cells than the other type of herbicides. Based on oxygen evolution, 60% inhibition was observed by the 10% aqueous extracts of Polygonum hydropiper, while there was 100% inhibition by the 10% methanol extracts of Polygonum hydropiper. This assay gave well correlated results to the Hill reaction data using isolated thylakoids. Thus liverwort photoautotrophic cells might be suitable materials for rapid screening method for photosynthetic inhibitory herbicides.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.199-204
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• 2015

In this study, prevention methods of radial cracks generated inside of artificial lightweight aggregate made of reject ash and dredged soil were investigated. The reject ash and dredged soil had mixed with weight ratio of 7 : 3 and formed to spheric shape of 5~20 mm diameter, then, the aggregates were manufactured using flash sintering method at $1200^{\circ}C$ for 10 min. The formation of radial cracks in the aggregates were suppressed as the size of specimen decreased. Also, the addition of silica to aggregates had prevented generation of the radial cracks. As the size and the amount of silica powder added increased, the development of radial cracks was constrained. Therefore the artificial lightweight aggregate manufactured in this study expected to be applicable to many fields such as construction and environmental usages. Also it is expected to contribute greatly to increase the recycling rate of reject ash and dredged soil.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.320-325
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• 2018

Hepatitis E virus (HEV) infection accounts for 20 million annual infections worldwide. HEV can be fatal in approximately 20-30% of pregnant women. HEV infections are normally self-limiting and mostly asymptomatic. However, in patients with insufficient immunity, such as acquired immunodeficiency syndrome patients, chronic and often fatal infections may ensue. Therefore, it is likely that host immune responses, especially interferon responses, play a critical role in HEV infection control. Here, we report that an HEV-encoded non-structural protein down-regulates type I interferon response. In addition, some other immune genes involved in the induction of type I interferon may be regulated as well. Detailed molecular mechanisms are currently being studied.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.150.1-150.1
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• 2010

가스 하이드레이트는 물분자와 저분자량의 가스분자가 고압과 저온에서 수소결합을 이루며 형성되는 결정성 화합물을 말한다. 최근 가스 하이드레이트의 물리적 특성과 형성 원리를 이용하여 다양한 분야로의 적용 연구가 수행되고 있는데 이의 효과적 달성을 위해서는 가스 하이드레이트의 상평형 연구가 필수적이다. 기존에 수행되는 상평형 실험 방법은 온도의 변화에 따라 하이드레이트를 해리시키고 압력의 변곡점을 찾는 것으로 최소 24시간이 소요되지만, 본 연구진이 제안하는 QCM을 이용한 방법은 1 ng의 무게에 1 Hz의 변화를 나타내는 수정진동자의 민감성을 이용한 것으로 약 2~3시간 내에 상평형 실험을 수행할 수 있고, 하이드레이트의 기억효과(Memory Effect)를 이용하여 연속적인 상평형 실험도 가능하다. 본 연구에서는 QCM 반응기의 원리 및 실험 방법에 대하여 설명하고 열역학적 촉진제를 첨가한 상평형 실험결과를 제시함으로써 상대적으로 저렴한 가격으로 다양한 촉진제와 억제제 첨가 시 나타나는 상평형 효과를 빠른 시간 내에 선별할 수 있는 방법으로 QCM을 이용한 방법을 제안하고자 한다.

• Journal of the Korean Society of Visualization
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• v.13 no.2
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• pp.33-37
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• 2015

매년 장마철에는 수막현상으로 인한 교통사고가 빈번하게 발생한다. 본 연구는 수막 형성 억제를 위해 타이어 앞부분에 설치되는 공기 분사 장치의 성능을 평가하는 것으로서, 공기 분사에 의한 수막 형성 억제를 모사할 수 있는 실험 장치를 제작하고, 수막 형성 억제 과정을 가시화하여 공기 분사 장치의 성능을 파악하고자 한다. 실험 변수로서 노즐의 형상 3가지와 수막에 대한 분사각 3가지에 대해 상세히 그 영향을 조사하였으며, 그 결과 분사각은 10도(지면에 대해서는 80도), 노즐 형상은 일자형일 때 수막 억제 효과가 가장 큰 것으로 파악되었다.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.254-259
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• 2011

Growing evidence indicates that oxidized low density lipoprotein (LDL) may promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The inhibitory effected on the susceptibility of human LDL to $Cu^{2+}$ or macrophages induced oxidation was investigated by monitoring thiobarbituric acid reactive substances(TBARS). Organosulfur compounds of garlic oil contains diallyldisulfide, diallyltrisulfide, diallyltetrasulfide, and diallyl pentasulfide in order. Garlic oil inhibited LDL oxidation by $Cu^{2+}$, or macrophages in a dose dependently, with a 20~60 ${\mu}g$, as increased TBARS assay. Garlic oil, at 60 ${\mu}M$, almost completely inhibited macrophages induced increase in electrophoretic mobility of LDL. When compared with several other antioxidants, probucol showed highest ability, and then garlic oil showed a much higher ability than natural occurring antioxidants, ${\alpha}$-tocopherol and ascorbic acid. The results suggested that garlic oil might play the inhibitory effects in the process of LDL oxidation.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.30-31
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• 2011

본 논문은 LCL필터를 이용한 분산전원용 계통연계형 PCS의 공진 억제 기법들을 비교 분석하였다. 주요 비교대상은 기존의 커패시터 전류를 읽어오는 가상 저항 기법과 커패시터 전압을 읽어오는 공진 억제 기법이며, 각 기법의 장단점과 정상상태 THD 분석을 모의 실험으로 비교하였다.