• Current Photovoltaic Research
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• 제2권3호
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• pp.88-94
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• 2014

The structural, optical and electrical properties of sputter-deposited CIGS films were directly influenced by the sputtering process parameters such as substrate temperature, working pressure, RF power and distance between target and substrate. CIGS thin films deposited by using a quaternary target revealed to be Se deficient due to Se low vapor pressure. This Se deficiency affected the overall stoichiometry of the films, causing the films to be Cu-rich. Current tends to pass through the Cu-Se channels which act as the shunting path increasing the film conductivity. The crystal structure of CIGS thin films depends on the substrate orientation due to the influence of surface morphology, grain size and stress of Mo substrate. The excess of Cu was removed from the CIGS films by KCN treatment, achieving a suitable Cu concentration (referred as Cu-poor) for the fabrication of solar cell. Due to high Cu concentrations on the CIGS film surface induced by Cu-Se phases after CIGS film deposition, KCN treatment proved to be necessary for the fabrication of high efficiency solar cells. Also during KCN treatment, dislocation density and lattice parameter decreased as excess Cu was removed, resulting in increase of bandgap and the decrease of conductivity of CIGS films. It was revealed that Cu-Se secondary phase could be removed by KCN wet etching of CIGS films, allowing the fabrication of high efficiency absorber layer.

• 한국응용과학기술학회지
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• 제20권2호
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• pp.94-100
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• 2003

We studied electrochemical characteristics of Langmuir-Blodgett(LB) films by using cyclic voltammetry with a three-electrode system. An Ag/AgCl as a reference electrode, a platinum wire as a counter electrode and LB film-coated indium tin oxide(ITO) as a working electrode were used to study electrochemical characteristics at a various concentration of $NaClO_4$ solution. LB films were reduced from initial potential to -1350 mV, continuously oxidized to l650mV and returned to the initial point. The scan rate was l00mV/s. The monolayer surface morphology of the LB film have been measured by Atomic Force Microscope(AFM). As a result, We comfirmed that the microscopic properties of LB film by AFM showed the good orientation of momolayer molecules and the thickness of monolayer was 3.5-4.lnm. The cyclic voltammograms(CV) of the ITO-coated glass showed the peak potentials for the reduction-oxidation reation. LB films of 4-octyl-4'-(5-carboxypentamethyleneoxy) azobenzene(8A5H) / L-${\alpha}$-phosphayidyl choline, dilauroyl(DLPC) seemed to be irreversible process caused by only the oxidation current from the cyclic voltammogram. The current of oxidatation increased at cyclic voltammogram by increasing 8A5H density in LB films. The diffusivity(D) of LB films increased with increasing of a 8A5H amount and was inversely proportional to the concentration of $NaClO_4$ solution.

• 한국표면공학회지
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• 제48권6호
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• pp.297-302
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• 2015

Nanocrystalline diamond(NCD) coated aluminium plates were prepared and applied as heat sinks for LED modules. NCD films were deposited on 1 mm thick Al plates for times of 2 - 10 h in a microwave plasma chemical vapor deposition reactor. Deposition parameters were the microwave power of 1.2 kW, the working pressure of 90 Torr, the $CH_4/Ar$ gas ratio of 2/200 sccm. In order to enhance diamond nucleation, DC bias voltage of -90 V was applied to the substrate during deposition without external heating. NCD film was identified by X-ray diffraction and Raman spectroscopy. The Al plates with about 300 nm thick NCD film were attached to LED modules and thermal analysis was carried out using Thermal Transient Tester (T3ster) in a still air box. Thermal resistance of the module with NCD/Al plate was 3.88 K/W while that with Al plate was 5.55 K/W. The smaller the thermal resistance, the better the heat emission. From structure function analysis, the differences between junction and ambient temperatures were $12.1^{\circ}C$ for NCD/Al plate and $15.5^{\circ}C$ for Al plate. The hot spot size of infrared images was larger on NCD/Al than Al plate for a given period of LED operation. In conclusion, NCD coated Al plate exhibited better thermal spreading performance than conventional Al heat sink.

• 대한화학회지
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• 제39권6호
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• pp.453-458
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• 1995

Pb^{2+}$을 Pseudomonas alcaligenes 5S rRNA의 구조 분석에 응용하였다. Pb^{2+}$이 5S rRNA를 절단하는 방식은 5S rRNA의 삼차구조의 조사에 이용할 수 있을 것으로 기대되는 몇 가지 특징들을 보였다. Pb^{2+}$은 안정한 나선형 줄기들에는 작용하지 않는다. 단일가닥으로된 구역들 또는 내밀린 부분들은 그들의 분자내에서의 위치에 따라 다른 민감도로 작용을 받는다. 불안정한 d 나선은 전혀 작용을 받지 않는다. 불안정한 C 줄기에서는 3'쪽의 가닥만이 작용을 받고 5'쪽의 가닥은 작용을 받지 않는다. Pb^{2+}$에 의한 절단과 Xanthomonas celebensis 5S rRNA의 구조분석의 결과들에 기초하여 우리는5S rRNA에서의 삼차상호작용에 대한 작업가설을 제안하였다.

• Spatial Information Research
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• 제9권2호
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• pp.341-352
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• 2001

이 연구는 지리정보시스템(GIS)로 구한 토지생산성지수(FPI)와 노동생산성지수(LPI)를 적용하여 농지의 잠재생산성지수(PPI)를 산정할 수 있는 모형을 개발하였고, 최근 경지정리사업이 완료된 지구에 적용하여 개발된 모형의 적용성을 검토하였다. 토지 생산성지수(FPI)는 분석대상지역의 토양 특성 Poly Grid를 중첩하여 결정하였으며, 노동생산성 지수(LPI)는 직접생산비중 GIS Network 분석으로 구한 통작거리와 논지분포에 따른 노력비 추가분을 전체 직접생산비에 대하 비율로 환산하였다. 마수지구와 원천지구의 개별 농지에 대한 전체생산성지수(PPI)는 각각 0.967∼0.712, 0.986∼0.780으로 비교적 큰 변이를 나타낼 수 있어 농지 평가에 대한 객관적인 자료로 적용할 수 있을 것이다. 농지의 잠재생산성지수를 경지정리 사업의 환지사업, 농민상호간에 농지교환 및 합병사업에 적용함으로써 농지의 규모화 및 집단화을 유도하고 농지생산성을 극대화할 수 있을 것이다.

• 복식
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• 제61권10호
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• pp.55-71
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• 2011

Court ladies' tasks were largely divided into two. First, if there is a royal family event, such as the royal family's wedding or feast, they followed the rules and regulations of work division that was defined in "Gyeonggukdaejeon". Secondly, during normal days, they were divided into Jimil (至密), Chimbang (針房), Subang (繡房), Sesugan (洗手間), Saenggwabang (生果房), Naesojubang (內燒廚房), and Oesojubang (外燒廚房) and took charge of female work that was needed daily at the palace including serving, cooking, laundry, needlework, embroidery, cleaning, and nurturing. This organization was operated by different palaces such as the daejeon(king's palace), daebijeon(queen dowager's palace), junggungjeon(queen's palace), or sejagung(prince's palace). Court ladies were selected among female slaves of the government office or naesusa(a ministry of royal household properties). Although commoners were forbidden to be selected, they sometimes became court ladies voluntarily for financial reasons or because of the will of their parents. Court ladies had different appearances according to the division they belonged to. The court girls of Jimil, Chimbang, and Subang wore saeangmeori while court girls from other places had braided hairstyles. At Jimil, they wore all different kinds of chima(skirt) and jeogori(jacket). Usually, court ladies wore navy chima, jade jeogori, green gyeonmagi(top jacket) with the uyeomeori hairstyle. When working in the evening, they wore pink jeogori or yellow-green jeogori, navy chima with the jojimmeori hairstyle for easiness to stay up all night and work. Navy chima was worn by court ladies. If there was a royal family event upper court ladies wore uyeomi, black or green wonsam, and stewards wore garima and dangui.

• 복식
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• 제64권8호
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• pp.1-19
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• 2014

The purpose of this study is to do an in-depth examination of Korean women in their 30's on the characteristics of their online fashion shopping, clothes-wearing, and presentation. In-depth interview and quantitative analysis were conducted as study methods. Results of this in-depth analysis showed that the factor with the most significant influence in their lifestyle was "childbirth." Childbirth was a major factor during fashion shopping and clothes-wearing. Also the results showed that the reason they used online shopping was for convenience, efficiency, rationality, pursuit of information, variety, and hedonism. In particular, women in their 30's had a higher motivation for efficiency and rationality compared to those in their 20's, and of those women, married working women showed the highest preference for fashion soho malls. Meanwhile, full-time homemakers, who pursued rationality, used open markets to search for fashion items based on price. Furthermore, the factors that women in their 30's considered during online shopping were price, design, purpose or situation for wearing the clothing, respectively. Compared to the women in their 20's, they emphasized recommendation, product properties, credibility, economy more than women in their 20's. Factors such as marriage and childbirth were more influential than occupation. Meanwhile, the factors that women in their 30's considered for wearing and presentation were time, place, and occasion(TPO), which all showed high importance in in-depth interview and quantitative analysis. Other factors were 'suitable image to self' and 'covering up body figure.'

• 한국지역사회생활과학회지
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• 제22권4호
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• pp.615-621
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• 2011

This study was conducted to evaluate of the protection efficiency in each part of developed pesticide-proof clothes by repeated washings. We investigated the effect of repeated laundering on mechanical properties of pesticide-proof clothes (not washed vs 5 times washed). We also examined pesticide infiltration rate into the pesticide-proof clothes by repeated laundering. The patches(TCL paper, surface area 50cm2)were attached to the inside of pesticide-proof clothes(head, chest, right upper-arm, right forearm, left thigh, left calf, back) which subjects had dressed in during pesticide spraying. The patches were detached from working clothes after work. For the extraction of pesticide in pesticide-proof clothes, sonication was applied for 30 min with methanol. The gas chromatography/mass spectrometry (GC/MS) was applied to identify the pesticide component. The results of this study are as follows: The force strength, water-vapour resistance and surface wetting resistance of pesticide-proof clothes decreased 5 times more in washed clothes. The concentration of pesticide was the highest in the head area of pesticide-proof clothes. In seven parts of TLC paper attached to the pesticide proof clothes, the concentration of pesticide was higher in the left thigh. The penetration part and concentration of pesticide increased as washing was repeated. Therefore the conclusion which can be drawn from this study is this: protection efficiency of pesticide-proof clothes decrease by repeated washings.

• 대한기계학회논문집A
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• 제34권11호
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• pp.1727-1732
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• 2010

고소작업차는 최근 건물이 초고층화됨에 따라 그 필요성이 더욱 커지고 있으나 그 이용에 따른 사고가 빈번하게 발생하고 있다. 고소작업차 붐대 및 유압기기를 구성하는 부품 손상은 탑승인원이 많은 경우 다수의 피해자가 추락으로 인해 사망에 이를 수 있다는 점에서 큰 문제를 안고 있으며 또한 유사 사고가 다시 발생할 수 있는 점이 내재되어 있어 그 심각성은 매우 크다고 할 수 있다. 이에 법공학적인 측면에서 좀 더 전문화되고 체계적인 사고조사와 원인 규명을 통해서 사전에 예방대책을 마련함으로써 유사 및 동종재해의 발생을 최소화해야 한다. 본 연구에서는 파단면 검사를 통한 부품 파손형태 검사 및 재료 물성평가 등을 통해 기계부품 파손에 의한 추락 사고에 관한 정확한 사고 원인을 규명함으로써 동일 형태의 안전사고 예방에 기여하고자 한다.

• Journal of Ginseng Research
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• 제42권3호
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• pp.298-303
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• 2018

Background: Panax ginseng is one of the most commonly used medicinal herbs worldwide for a variety of therapeutic properties including neurocognitive effects. Ginsenoside Rg1 is one of the most abundant active chemical constituents of this herb with known neuroprotective, anxiolytic, and cognition improving effects. Methods: We investigated the effects of Rg1 on the medial prefrontal cortex (mPFC), a key brain region involved in cognition, information processing, working memory, and decision making. In this study, the effects of systemic administration of Rg1 (1 mg/kg, 3 mg/kg, or 10 mg/kg) on (1) spontaneous firing of the medial prefrontal cortical neurons and (2) long-term potentiation (LTP) in the hippocampal-medial prefrontal cortical (HP-mPFC) pathway were investigated in male Sprague-Dawley rats. Results: The spontaneous neuronal activity of approximately 50% the recorded pyramidal cells in the mPFC was suppressed by Rg1. In addition, Rg1 attenuated LTP in the HP-mPFC pathway. These effects were not dose-dependent. Conclusion: This report suggests that acute treatment of Rg1 impairs LTP in the HP-mPFC pathway, perhaps by suppressing the firing of a subset of mPFC neurons that may contribute to the neurocognitive effects of Rg1.