• Journal of the Korean Data and Information Science Society
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• 제3권1호
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• pp.25-31
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• 1992

Some results relating to $C_{0}(R)\;and\;L^{1}(R)$ spaces with application to kernel density estimators will be introduced. First, random elements in $C_{0}(R)\;and\;L^{1}(R)$ are discussed. Then, complete convergence limit theorems are given to show that these results can be used in establishing uniformly consistency and $L^{1}$ consistency.

• Elastomers and Composites
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• 제50권3호
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• pp.217-222
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• 2015

Carbon-nickel nanocomposites were prepared by the reaction of fullerene ($C_{60}$) and nickel hydroxide in an electric furnace at $700^{\circ}C$ for 2 h. The hybrid carbon-nickel nanocomposites were characterized by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The kinetics and catalytic activity of the carbon-nickel nanocomposites in the reduction of 4-nitrophenol were confirmed by UV-vis spectroscopy.

• 한국전기전자재료학회논문지
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• 제33권5호
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• pp.373-379
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• 2020

In this study, TiN-coated cBN (cubic-structure boron nitride) powders were successfully synthesized by a sol-gel method using titanium (IV) isopropoxide (TTIP) and by controlling the heat treatment conditions. After the sol-gel process, amorphous nano-sized TiO_x was uniformly coated on the surface of cBN powder particles. The obtained TiO_x-coated cBN powders were heated at 1,000~1,300℃ for 1 or 6 h in a flow of 95%N₂-5%H₂ mixed gas. With increasing temperature, the chemical composition of the TiO_x coating layer changed in the order of TiO₂→Ti₆O₁₁→Ti₄O₇→TiN due to reduction of the Ti ions. The TiN coating layer was observable in the samples heated at 1,200℃ and appeared as the main phase in the sample heated at 1,300℃. The resulting thickness of the TiN coating layer of the sample heated at 1,300℃ was approximately 45~50 nm.

• 한국융합학회논문지
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• 제9권10호
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• pp.103-108
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• 2018

본 연구는 액션러닝을 활용한 수업이 대학생의 4C 핵심역량에 미치는 융합적 효과에 대해 파악하고자 한다. 부산광역시 일부 치위생(학)과 학생을 대상으로 액션러닝 수업 전과 후로 동일한 설문조사를 실시하였다. 수집된 자료는 SPSS 24.0 프로그램으로 대응표본 t-검증으로 비교 분석하였다. 액션러닝 수업을 실시하기 전 후 의사소통능력, 비판적사고 성향, 창의적 문제해결능력과 협력적 자기효능감 점수를 비교한 결과 수업을 실시하기 전보다 수업을 진행한 후의 각 영역별 점수가 높게 나타났고, 하위요인에서도 유의한 결과를 나타내었다(p<0.001). 결국 액션러닝을 활용한 수업은 제 4차 산업혁명시대가 요구하는 4C 핵심역량에 영향을 미친다는 것을 알수 있었고, 지식위주의 수업이 아닌 자기주도적인 수업방법의 변화가 시급하다고 판단된다.

• Preventive Nutrition and Food Science
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• 제21권4호
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• pp.317-322
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• 2016

Mitochondrial biogenesis is a complex process requiring coordinated expression of nuclear and mitochondrial genomes. The peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-$1{\alpha}$) is a key regulator of mitochondrial biogenesis, and it controls mitochondrial DNA (mtDNA) replication within diverse tissues, including muscle tissue. The aim of this study was to investigate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on mtDNA copy number and PGC-$1{\alpha}$ promoter activity in $C_2C_{12}$ muscle cells. mtDNA copy number and mRNA levels of genes related to mitochondrial biogenesis such as PGC-$1{\alpha}$, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (Tfam) were assayed by quantitative real-time PCR. The PGC-$1{\alpha}$ promoter from -970 to +412 bp was subcloned into the pGL3-basic vector, which includes a luciferase reporter gene. Both EPA and DHA significantly increased mtDNA copy number, dose and time dependently, and up-regulated mRNA levels of PGC-$1{\alpha}$, NRF1, and Tfam. Furthermore, EPA and DHA stimulated PGC-$1{\alpha}$ promoter activity in a dose-dependent manner. These results suggest that EPA and DHA may modulate mitochondrial biogenesis, which was partially associated with increased mtDNA replication and PGC-$1{\alpha}$ gene expression in $C_2C_{12}$ muscle cells.

• 센서학회지
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• 제22권2호
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• pp.124-129
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• 2013

In this paper, we manufactured the regenerated FBG by the thermal annealing of seed FBG based on UV irradiation. The writing conditions of regenerated FBGs were investigated in four types of optical fiber. FBGs written in $H_2$-free fiber were erased and not regenerated during the thermal annealing. FBG written in $H_2$ loaded Boron co-doped fiber was erased at the temperature of about $580^{\circ}C$ and regenerated about $590^{\circ}C$. However, the extinction of regenerated FBG started at the temperature over $900^{\circ}C$ and then FBG disappeared out. FBG written in $H_2$ loaded Ge high doped fiber was erased and regenerated around the temperature of $800^{\circ}C$ and maintained until the end of the thermal annealing. The reflection of the regenerated FBG was decreased about 12 dB and the center wavelength of the regenerated FBG was shifted about 0.7 nm compared with that of the seed FBG. The thermal characteristics of the regenerated FBG were analyzed by reheating from room temperature to $980^{\circ}C$. As results, the regenerated FBG had survived without a decrease of reflection and the thermal sensitivity was $15pm^{\circ}C$.

• 한국융합학회논문지
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• 제8권7호
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• pp.231-236
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• 2017

본 연구에서는 고분자재료인 CFRP(Carbon Fiber Reinforced Plastic)과 구조용 금속인 SM45C로 이루어진 이종 복합재료가 경량화 재료용으로 사용되고 있다. SM45C를 심재로 갖고 양면에 섬유 적층각도가 다른 단반향 CFRP를 접착시킨 샌드위치형 복합재료를 이용하여 CT(Compact Tension)시험을 기초로 한 유한요소 해석을 진행하였다. CT시험은 하중을 받는 재료내의 크랙으로 인한 파괴거동을 확인하기 위한 대표적인 방법이다. 이종 복합재료를 기계 구조물에 적용하기 위해서는 크랙 및 구멍에 대한 영향을 연구하여야 한다. 샌드위치형 복합재료의 CT시험에 의한 파괴거동을 시뮬레이션 해석으로 연구하였다. 본 연구 결과로서, [0/60/-60/0]의 적층각도를 가진 단방향 CFRP 샌드위치형태 복합재료가 우수한 강도를 갖으며 최대 등가응력은 약 182GPa정도가 나타났다. 또한 복합 재료 형상으로서의 디자인적 요소를 융합 기술에 접목함으로서 그 미적인 감각을 나타낼 수 있다.

• 한국자기공명학회논문지
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• 제26권1호
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• pp.10-16
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• 2022

The phase transition temperatures of CsCoCl₃·2H₂O crystals are investigated via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Three endothermic peaks at temperatures of 370 K (=T_C1), 390 K (=T_C2), and 416 K (=T_C3) were observed for phase transitions from CsCoCl₃·2H₂O to CsCoCl₃·1.5H₂O, to CsCoCl₃·H₂O, and then to CsCoCl₃·0.5H₂O, respectively. In addition, the spin-lattice relaxation time T_1ρ in the rotating frame and T₁ in the laboratory frame as well as changes in chemical shifts for ¹H and ¹³³Cs near T_C1 were found to be temperature dependent. Our analyses results indicated that the changes of chemical shifts, T_1ρ, and T₁ are associated with structural phase transitions near temperature T_C1. The changes of chemical shifts, T_1ρ, and T₁ near T_C1 were associated with structural phase transitions, owing to the changes in the symmetry of the structure formed of H₂O and Cs⁺ ions. Consequently, the structural symmetry in CsCoCl₃·2H₂O crystals based on temperature is discussed by the environments of their H and Cs nuclei.

• 한국융합학회논문지
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• 제11권10호
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• pp.237-241
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• 2020

본 연구에서는 실제형상과 같은 회전날개들을 가진 세 개의 세탁기의 모델들에 대하여 유동해석을 하였다. 회전날개의 좌측, 우측 및 바닥 평면들에 대한 압력 및 속도들에서는, 전반적으로 Model C가 유동에 대한 압력이 가장 크게 나와서 Model A에 비하여 2배 이상 나타났고, Model B와 Model A순으로 되었다. Model A, B 및 C의 회전 블레이드 측면에서의 유동의 유선속도들을 보면, 전반적으로 Model C가 유동에 대한 속도가 가장 크게 나와서 Model A에 비하여 1.7배 가량 나타났고, Model B와 Model A순으로 되었다. 회전날개의 갯수가 많다고 해서 유동상태가 양호하다기 보다 Model C와 같이 Model A나 Model B에 비하여 날개의 개수가 적지만 날개의 하부 두께가 더 두꺼운 경우가 유동 압력 및 유동 속도가 커서 세탁성능을 향상시켜 준다는 것을 알 수 있다. 또한 본 연구가 실제적으로 세탁기 회전날개의 내구성이 있는 효율적인 설계와 그 회전 날개의 미적인 융합에 적합하여 보인다.

• BMB Reports
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• 제55권8호
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• pp.389-394
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• 2022

In particular, the phenomenon of c-Jun degradation within the inflammatory response has not yet been fully analyzed. In order to verify this, we investigated LPS-stimulated murine macrophages pre-treated with sodium orthovanadate (SO) in order to uncover the regulatory mechanisms of the MAPKs which regulate c-Jun degradation within the inflammatory response. Through our study, we found that SO suppressed the production of prostaglandin E₂ (PGE₂) and the expression of COX-2 in LPS-stimulated RAW264.7 cells. Additionally, SO decreased total c-Jun levels, without altering the amount of mRNA, although the phospho-levels of p38, ERK, and JNK were strongly enhanced. Through the usage of selective MAPK inhibitors, and knockdown and overexpression strategies, p38 was revealed to be a major MAPK which regulates c-Jun degradation. Further analysis indicates that the phosphorylation of p38 is a determinant for c-Jun degradation, and is sufficient to induce ubiquitination-dependent c-Jun degradation, recovered through MG132 treatment. Therefore, our results suggest that the hyperphosphorylation of p38 by SO contributes to c-Jun degradation, which is linked to the suppression of PGE₂ secretion in inflammatory responses; and thus, finding drugs to increase p38 activity could be a novel strategy for the development of anti-inflammatory drugs.