• Journal of Biosystems Engineering
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• 제41권4호
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• pp.365-372
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• 2016

Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.

• 한국산학기술학회논문지
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• 제12권9호
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• pp.3815-3826
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• 2011

본 연구는 아직 잘 알려지지 않은 고려말 조선초의 상류층 여성복식을 고증하여 구체관절인형의상 세트를 시험제작하고 한국 문화상품의 아름다움을 알리기 위한 것이다. 고려말 조선초의 상류층 여성복식은 풍성한 실루엣, 원과 명 복식과의 융합, 옛 고려풍의 부활, 발달한 모시 직조기술, 불교문화 복식이라는 특성을 가진다. 13-14C의 문헌과 유물과 회화를 통한 연구자의 고증과 패턴제작 과정을 거쳐 총 8점의 아이템이 외주제작되었다. 각 아이템은 세트로 구성되었으나 소비자가 단품으로 선택할 수 있으며 다양한 조합이 가능하다. 인체와 특성이 다른 구체관절인형의 바디로 인해 부분적으로 다아트와 작은 고름이 첨가되고 강직한 직물이 사용되었다. 이후로는 기성품 생산을 위한 업체 시스템 개발 연구가 필요하다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.276-279
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• 2004

Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

• 한국발생생물학회지:발생과생식
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• 제22권4호
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• pp.341-350
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• 2018

Chemokines is a small protein that plays a major role in inflammatory reactions and viral infections as a chemotactic factor of cytokines involved in innate immunity. Most of the chemokines belong to the chemokine groups CC and CXC. To investigate the immune system of the olive flounder (Paralichthys olivaceus), an expression pattern specifically induced in the early developmental stages of analysis is examined using qRT-PCR. We also examined tissue-specific expression of both CC and CXC chemokine in healthy olive flounder samples. CC and CXC chemokine shows increased expression after immune-related organs are formed compared to expression during early development. CC chemokine was more highly expressed in the fin, but CXC chemokine showed higher expression in the gills, spleen, intestines, and stomach. Spatial and temporal expression analysis of CC and CXC chemokine were performed following viral hemorrhagic septicemia virus (VHSV) infection. CC chemokine showed high expression in the gills, which are respiratory organs, whereas CXC chemokine was more highly expressed in the kidneys, an immune-related organ. These results suggest that CC and CXC chemokine play an important role in the immune response of the olive flounder, and may be used as basic data for the immunological activity and gene analysis of it as well as other fish.

• 한국결정성장학회지
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• 제31권6호
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• pp.240-246
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• 2021

도자 생산현장에서 아연결정유약을 제조하여 사용할 때 조성원료에 따라 유약의 결정생성이 불안정하고, 특히 결정이 잘 생성되는 유약도 습식제조 후 시간이 경과하면 결정생성이 급격히 저하되는 문제점이 있다. 도예가들이 주로 사용하는 산화아연(ZnO)과 하소아연(calcined ZnO), 프리트 3110, 그리고 규석을 출발 물질로 3성분계 실험을 통하여 아연결정 조성을 선택하고 선 연구된 소성 조건을 사용하였다. 유약을 제조하고 1일~24주까지 습식으로 보관하면서 침수 과정에서 아연이 아연결정유의 결정생성에 미치는 영향을 규명하고자 하였다. 원료 입도 및 침수 영향을 측정하기 위해 입도분석, XRD, Raman Spectroscopy 그리고 SEM 분석 등을 하였다. 연구결과, 산화아연은 습식으로 유약 사용 시 willemite 결정 생성 및 성장이 우수하지만 유약을 보관하는 동안 ZnO가 물과 반응하여 Zn(OH)2를 생성하고 응집되면서 유약내 ZnO량이 감소되어 willemite 생성을 저해하여 결정이 감소됨을 확인하였다.

• 한국사회정책
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• 제25권2호
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• pp.333-366
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• 2018

본 연구는 비행청소년의 사회적 자본 인식유형을 Q방법론을 활용하여 비행청소년의 사회적 자본 유형별 특성을 밝히고, 사회적 자본 형성방안을 모색하고자 한다. 이를 위해 사회적 자본에 관한 진술문 33문항을 비행청소년 16명을 대상으로 조사를 실시한 결과, 5가지의 유형이 도출되었다. 유형 I은 '친구 지지형', 유형 II는 '가족친화형', 유형 III은 '능력자형', 유형 IV는 '정의사회형', 유형 V는 '학교 신뢰형'으로 명명하였다. 이를 토대로 사회적 자본 형성방안을 제시해 보면, 첫째, 또래관계 내 사회적 자본을 향상시킬 수 있도록 친한 친구를 활용한 프로그램 개발이 요구된다. 둘째, 부모 자녀간의 직접적인 관계에서의 개입 즉, 대화, 관심, 의사소통 뿐만 아니라 자녀와 간접적으로 형성하고 있는 자녀의 친구, 자녀의 학교에 대한 개입이 요구된다. 셋째, 일상생활에서의 지속적인 감정 통제 능력을 조절할 수 있도록 개입할 필요가 있다. 넷째, 사회제도의 불합리성과 유해환경에 대한 감시감독을 강화할 필요가 있다. 마지막으로 학교 규범의 수준을 강화하여 학교에 대한 신뢰를 높일 수 있도록 환경을 개선할 필요가 있다.

• Tissue Engineering and Regenerative Medicine
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• 제15권6호
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• pp.711-719
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• 2018

BACKGROUND: Collagen organization within tissues has a critical role in wound regeneration. Collagen fibril diameter, arrangements and maturity between connective tissue growth factor (CTGF) small interfering RNA (siRNA) and mismatch scrambled siRNA-treated wound were compared to evaluate the efficacy of CTGF siRNA as a future implement for scar preventive medicine. METHODS: Nanocomplexes of CTGF small interfering RNA (CTGF siRNA) with cell penetrating peptides (KALA and $MPG^{{\Delta}NLS}$) were formulated and their effects on CTGF downregulation, collagen fibril diameter and arrangement were investigated. Various ratios of CTGF siRNA and peptide complexes were prepared and down-regulation were evaluated by immunoblot analysis. Control and CTGF siRNA modified cells-populated collagen lattices were prepared and rates of contraction measured. Collagen organization in rabbit ear 8 mm biopsy punch wound at 1 day to 8 wks post injury time were investigated by transmission electron microscopy and histology was investigated with Olympus System and TS-Auto software. CONCLUSION: CTGF expression was down-regulated to 40% of control by CTGF siRNA/KALA (1:24) complexes (p<0.01) and collagen lattice contraction was inhibited. However, down-regulated of CTGF by CTGF $siRNA/MPG^{{\Delta}NLS}$ complexes was not statistically significant. CTGF KALA-treated wound appeared with well formed-basket weave pattern of collagen fibrils with mean diameter of $128{\pm}22nm$ (n = 821). Mismatch siRNA/KALA-treated wound showed a high frequency of parallel small diameter fibrils (mean $90{\pm}20nm$, n = 563). CONCLUSION: Controlling over-expression of CTGF by peptide-mediated siRNA delivery could improve the collagen orientation and tissue remodeling in full thickness rabbit ear wound.

• 공업화학
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• 제22권3호
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• pp.328-331
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• 2011

ZnSe 양자점을 AOT 마이크로에멀전을 이용해서 제조하였으며, tetraethyl orthosilicate (TEOS)를 직접 주입하는 방법으로 실리카에 담지된 ZnSe 양자점 소재를 얻었다. 양자점이 실리카에 담지되었을 때, 상대적으로 고른 구 형태의 ZnSe 양자점을 얻을 수 있었고 그 크기는 약 7 nm이었다. 아울러 마이크로에멀전상의 ZnSe 양자점이 실리카에 담지되면 photoluminescence 효율은 8%에서 1.1%로 감소하였다. 그러나 금표면에 실리카에 담지된 ZnSe 고체 박막을 형성시켰을 때, 양자점의 광학안정성은 크게 증가함을 알 수 있었다. 특히 ZnSe 양자점은 카드뮴이 없어 독성이 작으며 기존의 ZnSe 제조 시 Se 전구체로 사용하는 맹독성의 $H_2Se$ 가스나 높은 반응 온도를 필요로 하지 않는다. 따라서 바이오센서용 등으로 사용이 가능한 실리카에 담지된 ZnSe 양자점을 안전하고 경제적인 방법으로 생산할 수 있는 방법을 제시할 수 있었다.

• Journal of Multimedia Information System
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• 제9권2호
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• pp.113-120
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• 2022

Mongolian folk songs are inspired by Mongolian labor songs and are classified into long and short songs. Mongolian long songs have ancient origins, are rich in legends, and are a great source of folklore. So it was inscribed by UNESCO in 2008. Mongolian written literature is formed under the direct influence of oral literature. Mongolian long song has 3 classes: ayzam, suman, and besreg by their lyrics and structure. In ayzam long song, the world perfectly embodies the philosophical nature of world phenomena and the nature of human life. Suman long song has a wide range of topics such as the common way of life, respect for ancestors, respect for fathers, respect for mountains and water, livestock and animal husbandry, as well as the history of Mongolia. Besreg long songs are dominated by commanded and trained characters. In this paper, we proposed a method to classify their 3 types of long songs using machine learning, based on their lyrics structures without semantic information. We collected lyrics of over 80 long songs and extracted 11 features from every single song. The features are the name of a song, number of the verse, number of lines, number of words, general value, double value, elapsed time of verse, elapsed time of 5 words, and the longest elapsed time of 1 word, full text, and type label. In experimental results, our proposed features show on average 78% recognition rates in function type machine learning methods, to classify the ayzam, suman, and besreg classes.

• 한국간호교육학회지
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• 제29권3호
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• pp.247-262
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• 2023

Purpose: This study aimed to identify the types of perception toward non-face-to-face clinical practice and to characterize the types of students who experienced online clinical practice during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Q-methodology was used in this study, and 270 Q populations were formed based on in-depth interviews with 10 nursing students who had experienced non-face-to-face clinical practice, as well as related literature. Interviews were performed from August 1 to 31, 2022. A total of 42 Q samples were extracted, and Q sorting was performed on 33 nursing students who had experienced non-face-to-face clinical practice. A Q factor analysis was performed using the PC-QUANL program. Results: The nursing students' perceptions of non-face-to-face clinical practice were classified into the following five types: "future professional competency-focused type," "realistic convenience priority type," "task burden awareness type," "negative critic type," and "limited experience dissatisfaction type." Conclusion: This study revealed non-face-to-face clinical practice's positive and negative aspects in nursing education. Moreover, it identified the aspects of clinical practice that cannot be replaced by non-face-to-face clinical practice and the elements of non-face-to-face practice that can complement clinical practice. These findings can be used as fundamental data to establish a stable and efficient system for improving the quality of clinical practice in the post-COVID-19 era and to implement effective non-face-to-face clinical practice according to student types.