코로나19로 인한 청소년의 경제적 상태 변화에 따른 한국 청소년의 식생활 및 건강에 미치는 영향

김호경,남형경,Kim, Ho-Kyoung,Nam, Hyong-Kyong 한국산업융합학회 2022 한국산업융합학회 논문집 Vol.25 No.5

This study aims to understand the influence of COVID-19 on youth daily life by analyzing the correlation between youth health and diet according to whether economic status has changed due to COVID-19 and to provide basic data on program construction for the welfare of socially marginalized adolescents. As a result of the study, the proportion of respondents who answered that there was a change in economic status at a high rate for decreased academic performance (p<0.001), stress perception, and suicidal thoughts (p<0.001), and the proportion of decreased number of breakfasts and increased fast food consumption (p<0.001) was also high. These results of the study are thought to be the reason for the increase in adolescents who are alienated due to changes in home conditions due to COVID-19, which is expected to affect the physical and mental health of adolescents who lack communication and guidance, and the increase in delinquents rate due to reduced academic concentration and increased junk food intake. Therefore, through this study, it can be helpful to use basic data for the development of welfare programs such as non-face-to-face as basic data for teenagers alienated from COVID-19.

유자의 항 Influenza 바이러스 A형 활성에 관한 연구

김호경,고병섭,전원경,Kim, Ho-Kyoung,Ko, Byoung-Seob,Jeon, Won-Kyung 한국생약학회 2000 생약학회지 Vol.31 No.1

To evaluate anti-influenza virus activity of 113 specimens of Korean traditional medicine both water and methanol extracts were examined using haemagglutination inhibition test. The water extract from Citrus junos was found to inhibit influenza virus A/Taiwan/l/86(H1N1). The survival rates of virus were determined by in situ cellular enzyme-linked immunosorbent assay. The water extract of Citrus junos was fractionated by chromatographic separating using Amberlite XAD-4, 40% MeOH and 60% MeOH layer had antiviral activity. The half inhibition concentration $(IC_{50})$ of 40% MeOH layer on survival of influenza virus was $MIC>361.5{\mu}g/ml$ and $IC_{50}$ value of fr. 40-4 fractionated from 40% MeOH layer was $677.19{\mu}g/ml$. These results suggested that the fractions of Citus junos have potent anti-influenza A virus activity.

엄나무 추출물이 3T3-L1 지방세포에서 인슐린 민감성과 인슐린 유사성 작용에 미치는 영향

김호경,박선민,고병섭,Kim, Ho-Kyoung,Park, Sun-Min,Ko, Byoung-Seob 한국응용생명화학회 2002 한국농화학회지 Vol.45 No.1

국내의 한약재 시장 등에서 당뇨병의 민간요법 약재로 많이 판매되고 있는 엄나무(Kalopanax pictus NAKAI)수피의 열수 추출물에서 인슐린성 물질과 인슐린 민감성 약제로서의 가능성을 탐색하기 위해 3T3-L1 섬유아세포(fibroblast)가 3T3-L1 지방세포(adipocytes)로 분화할 때 미치는 영향과 지방 세포내로의 포도당 섭취(glucose uptake)에 미치는 영향을 조사하였다. 엄나무의 수피를 열수 추출하고 동결건조하여 만든 분말 엑스시료를 증류수에 녹여 각각 $10{\mu}g/ml$ 및 $l{\mu}g/ml로$ 3T3-L1 섬유아세포를 처리한 후, 분화유도 물질만을 첨가한 대조군의 분화 정도를 100%로 정하였을 때 이에 대한 백분율로 환산하여 결정하였다. 분화유도물질이 첨가되지 않은 경우 $1{\mu}g/ml$와 $10{\mu}g/ml$의 농도에서 각각 $115.4{\pm}5.1%(p<0.05)$와 $122.3{\pm}2.1%(p<0.05)$로 유의성있게 분화를 촉진시켰다. 분화유도물질을 첨가하였을 때, $1{\mu}g/ml$에서는 $127.0{\pm}5.3%(p<0.001)$ 분화를 촉진시켰고, $10{\mu}g/ml$에서는 분화에 거의 변화가 없었다. 3T3-L1 지방 세포내로의 포도당 섭취량은 소량의 인슐린(3ng/ml)과 함께 $0{\sim}10%$ 메탄올 분획층(Fr. 1)과 30% 메탄올 분획층(Fr. 3)을 0.3와 $3{\mu}g/ml$ 첨가하였을 때 분획층을 첨가하지 않은 대조군에 비해 모두 $3.3{\pm}0.5$배 증가시켜 인슐린 50ng/ml에서 반응하였을 때와 유사한 섭취 정도를 나타내었다. 엄나무의 수피는 인슐린성 물질을 함유하고 있으며, 추출물을 분획한 Fr. 1과 Fr. 3은 인슐린 저항성을 감소시키는 물질이 함유되어 있어 인슐린 민감성 제재로 개발할 수 있는 가능성을 암시하고 있다. Effects of the water extract from Kalopanax pictus NAKAI on insulin-like action and glucose uptake in 3T3-L1 cells were investigated. The bark of K. pictus NAKAI was treated with hot water and the extract was freeze-dried. Total extract of K. pictus NAKAI was fractionated into 6 fractions with increasing gradients from 0 to 100% MeOH on Amberlite XDA-4. Treatment of 3T3-L1 fibroblasts with 1 ${\mu}g/ml$ and 10 ${\mu}g/ml$ of K. pictus NAKAI total extracts significantly increased the differentiation of the cells. When co-treated with inducers such a dexamethasone, 1-methyl-3-isobutylxanthine and insulin, the differentiation was increased at 1 ${\mu}g/ml$ of total extract, but not at 10 ${\mu}g/ml$. In 3T3-L1 adipocytes, glucose uptake was increased by 3.3 times with addition of 0.3 and 3 ${\mu}g/ml$ of Fr. 1 (0-10% MeOH) and Fr. 3 (30% MeOH) at 3 ng/ml insulin. In conclusion, K. pictus NAKAI contains such compounds that play a role of insulin-like action and insulin sensitizer.

A comparative electrical transport study on Cu/n-type InP Schottky diode measured at 300 and 100 K

김호경,Chan Yeong Jung,Se Hyun Kim,Yunae Cho,김동욱 한국물리학회 2016 Current Applied Physics Vol.16 No.1

Two oxygen plasma treated InP samples with different plasma powers of 100 and 250 W were prepared and a comparative study on the electrical properties of Cu/n-type InP Schottky diode measured at 300 and 100 K was performed to investigate the current transport mechanism in detail. The forward and reverse bias currentevoltage (IeV) characteristics were analyzed with considering various transport models. The fitting to the forward bias IeV characteristics revealed that relatively high ideality factor at 300 K for untreated sample were related with the generation-recombination (GR) current and the large E00 value at 100 K for 100 W plasma treated sample were associated with more significant tunneling effect. The analyses on the reverse bias current characteristics showed the suitable current transport model has changed from thermionic emission (TE) to TE combined with barrier lowering for both untreated and 250 W treated samples and from TE þ BL to thermionic field emission for 100 W treated sample with increasing temperature from 100 to 300 K.

알루미늄 고용체 합금의 고온변형 거동에 관한 연구

김호경,Kim, Ho-Gyeong 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.2

The creep characteristics of an Al-5wt.% Ag alloy including the stress exponent, the activation energy for creep and the shape of the creep curve were investigated at a normalized shear stress extending from $ 10^{-5}{\;}to{\;}3{\times}10^{-4}$ and in the temperature range of 640-873 K, where silver is in solid solution. The experimental results shows that the stress exponent is 4.6, the activation energy is 141 kJ/mole, and the stacking fault energy is $180{\;}mJ/m^2$, suggesting that the creep behavior of Al-5 wt.% Ag is similiar to that reported for pure aluminum, and that under the current experimental conditions, the alloy behaves as a class II(metal class). The above creep characteristics obtained for Al-5 wt.% Ag are discussed in the light of prediction regarding deformation mechanisms in solid solution alloys.

Characterization of Conduction Mechanism in Cu Schottky Contacts to p-type Ge

김호경,Se Hyun Kim,Chan Yeong Jung 한국전기전자재료학회 2014 Transactions on Electrical and Electronic Material Vol.15 No.6

Germanium (Ge) is a promising material for next generation nanoelectronics and multiple junction solar cells. This work investigated the electrical properties in Cu/p-type Ge Schottky diodes, using current-voltage (I-V )measurements. The Schottky barrier heights were 0.66, 0.59, and 0.70 eV from the forward ln(I)-V, Cheung, and Nordemethods, respectively. The ideality factors were 1.92 and 1.78 from the forward ln(I)-V method and Cheung method,respectively. Such high ideality factor could be associated with the presence of an interfacial layer and interface statesat the Cu/p-Ge interface. The reverse-biased current transport was dominated by the Poole-Frenkel emission ratherthan the Schottky emission.

$550^{\circ}C$에서의 2.25Cr-1Mo 강 용접부의 고온 균열성장 거동에 관한 연구

김호경,정강,정진성,Kim, Ho-Kyung,Chung, Kang,Chung, Chin-Sung 대한용접접합학회 2001 대한용접·접합학회지 Vol.19 No.3

Both creep deformation and creep crack growth experiments have been conducted on 2.25Cr-1Mo steel weldment in order to provided an information on residual life prediction of structural component weldment containing a crack. The stress exponent of creep deformation equation for the base metal and weldment at 823k were found to be 10.2 and 7.3, respectively. These two values could be assumed that dislocation climb processes are controlling the creep deformation of both materials. The creep rate of the weldment was very low, compared with that of base metal under the same applied stress. Whereas the creep crack growth rate of the weldment was almost twice higher than that of base metal under the fixed value of $C^*$. This may indicate that the weldment is stronger than the base metal in view of creep deformation and is brittle during creep crack growth due to the intrinsic microstructure of banite and relatively higher and Mn contents.

유전박막을 이용한 금속/반도체 계면 특성 및 결함 연구

김호경,Kim, Ho-Gyeong 한국전기전자재료학회 2018 전기전자재료 Vol.31 No.5

관심 끄는 제2의 중동, 카스피해 및 사할린

김호경,Kim, Ho-Gyeong 대한석유협회 2004 석유와 에너지 Vol.2004 No.3

도시가스산업의 발전전망

김호경,Kim, Ho-Gyeong 대한석유협회 1990 석유와 에너지 Vol.1990 No.8