• Journal of Powder Materials
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• v.19 no.6
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• pp.416-423
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• 2012

This paper introduces an effect of a preparing $ZrO_2$-Ag composite on its mechanical properties and microstructure. In present study, $ZrO_2$-Ag was prepared by reduction-deposition route and wetting dispersive milling method, respectively. Two type of Ag powders (nano Ag and micron Ag size, respectively) were dispersed into $ZrO_2$ powder during wetting dispersive milling in D.I. water. Each sample was sintered at $1450^{\circ}C$ for 2hr in atmosphere, and then several mechanical tests and analysis of microstructure were carried out by bending test, hardness, fracture toughness and fracture surface microstructure. As for microstructure, the Ag coated $ZrO_2$ showed homogeneously dispersed Ag in $ZrO_2$ in where pore defect did not appear. However, $ZrO_2$-nano Ag and $ZrO_2$-micro Ag composite appeared Ag aggregation and its pore defect, which carried out low mechanical property and wide error function value.

• Journal of the Korea Convergence Society
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• v.6 no.5
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• pp.91-98
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• 2015

Recent domestic university has emerged need to convergence education. Health related department College students must deal with a lot of exams. The test anxiety can cause physiological and psychological problems. To solve this problem, it is necessary examine the relationship between test anxiety and self-esteem. This study Health related department College students conducted questionnaire survey of 301 students. In general the overall average is 2.98 according to the characteristics of self-esteem and gender, boys, if older, the older the more self-esteem was higher. Test anxiety of the general characteristics showed little higher this year. Test anxiety is higher self-esteem was low. The effect o the general characteristics and test anxiety self-esteem, in the case of boys, seniors, if I choose this self-esteem was higher, the higher the anxiety test were analyzed by low self-esteem. Therefore, need to a systematic curriculum approach and academic environment.

• Journal of the Korea Convergence Society
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• v.7 no.2
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• pp.109-118
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• 2016

The purpose of this study was I cultivate practical ability to solve diverse and complex issues in the field of convergence and applied learning and practical training element through problem-based learning to preliminary sports leaders. Selected students in grades 3 to 28 Sports Science S university people to them as participants and through a qualitative case study methods, such as group interviews, participant observation, open questionnaire and the following results were obtained. First, the level of satisfaction on class was high and the class was evaluated with significant contemplation. Second, it has been collecting a variety of learning materials to understand, interpret and improve the ability to solve practical problems in the process of actively reconstruct their own knowledge structure. It also gave a positive impact on the creative and divergent thinking to accelerate the promotion of autonomy. Third, opinions about teamwork, sharing your thoughts with colleagues point is that you can see yourself in other people's positions were evaluated as positive effects.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.546-552
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• 2018

A comprehensive collection of proteins senses local changes in intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular $Ca^{2+}$ concentrations in cat esophageal smooth muscle cells. To measure $[Ca^{2+}]_i$ levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in $[Ca^{2+}]_i$ in the cells. Pretreatment with EGTA, an extracellular $Ca^{2+}$ chelator, decreased the S1P-induced increase in $[Ca^{2+}]_i$, and an L-type $Ca^{2+}$-channel blocker, nimodipine, decreased the effect of S1P. This indicates that $Ca^{2+}$ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an $InsP_3$ receptor blocker, the S1P-evoked increase in $[Ca^{2+}]_i$ was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of $G_i$-protein, suppressed the increase in $[Ca^{2+}]_i$ evoked by S1P. These results suggest that the S1P-induced increase in $[Ca^{2+}]_i$ in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of $Ca^{2+}$ from the $InsP_3$-sensitive $Ca^{2+}$ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular $Ca^{2+}$ via the L type $Ca^{2+}$ channel, which was dependent on activation of the $S1P_4$ receptor coupled to PTX-sensitive $G_i$ protein, via phospholipase C-mediated $Ca^{2+}$ release from the $InsP_3$-sensitive $Ca^{2+}$ pool in cat esophageal smooth muscle cells.

• Journal of Life Science
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• v.30 no.4
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• pp.331-342
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• 2020

The suppression of neuroinflammatory responses in microglial cells can be considered a key target for improving the progression of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). Asparagus cochinchinensis has traditionally been used as a medicine to treat fever, cough, kidney disease, breast cancer, inflammatory diseases, and brain diseases. In this study, we investigated the neuroprotective mechanism of an aqueous extract from A. cochinchinensis root (AEAC), particularly its anti-inflammatory effects on lipopolysaccharide (LPS)-activated BV-2 microglial cells. BV-2 cells were treated with four different concentrations of AEAC. No significant toxicity was detected in BV-2 cells treated with AEAC. Nitric oxide (NO), cyclooxygenase-2 (COX-2) mRNA, and inducible nitric oxide synthase (iNOS) mRNA levels were 21% lower in the AEAC+LPS group than in the Vehicle+LPS group. Lower proinflammatory (TNF-α and IL-1β) and anti-inflammatory cytokine (IL-6 and IL-10) levels were also detected in the AEAC+LPS group than in the Vehicle+LPS group, albeit at varying rates. Moreover, the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group compared to the Vehicle+LPS group, enhancement of the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group, while cell cycle arrest at the G2/M phase caused by LPS treatment was less severe in the AEAC+LPS group. The increase in reactive oxygen species (ROS) generation induced by LPS treatment was also lower in the AEAC-pretreated group than in the Vehicle+LPS group. This is the first study to show that AEAC exerts anti-neuroinflammatory activity against LPS stimulation by regulating the MAPK signaling pathway, the cell cycle, and ROS production.

• Cartoon and Animation Studies
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• s.48
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• pp.45-67
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• 2017

Many of the modern animations have 3D technology, and as time goes by, their production technology becomes more diverse and sophisticated. When John Alan Lasseter insisted on studying CG animation technology, he might have taken our jobs to the computer in the near future, as many people were worried about. It may be premature to worry that an unstable future may become a reality at this point, but I do not think there will be any difference in the fact that many animations are being produced using 3D technology. Since the Toy Story was screened in 1995, the 3D animation production technology has started to develop rapidly and now it has been elaborately developed so that it can not distinguish the part where computer graphics technology is applied from the live film. On the other hand, Disney's 2D animation part falls into the decline path because the appearance of 3D animation was perceived as a new expression technique at that time, and the efficiency of the work process was superior to the 2D animation in addition to receiving the attention from the audience. Is it necessary to accept the retrogression of 2D animation technology, reflecting the environment of the animation industry that 3D animation production technology has become mainstream in the first 20 years since the first theatrical works appeared? Since 2D animation technology has a long history and is still attractive to the audience, it is not hard to find an attempt to combine 2D and 3D animation technology. In this paper, I want to study 2D hand - drawn character in 3D animation. Through this, it is hoped that animation convergence technology will be applied more actively in the future.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.81-88
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• 2018

Human gingival fibroblast (HGF) is the main cell type existed in periodontium and produces a variety of inflammatory mediators by external stimuli. In this study, the anti-inflammatory activity of Porphyra yezoensis ethanol extract (PYEE) on LPS-PG lipopolysaccharide from Porphyromonas gingivalis activated HGF-1 cell. Up-regulated iNOS and COX-2 expressions by LPS-PG were significantly attenuated by PYEE treatment in a dose-dependent manner. In addition, activated nuclear factor $(NF)-{\kappa}B$ was also dose-dependently inhibited by PYEE treatment. Among upstream signaling molecules, PYEE treatment inhibited phosphorylation of c-Jun $NH_2$-terminal kinase (JNK) but did not give any effect on other molecules. On the other hand, one of phase II enzymes, NAD(P)H:quinone dehydrogenase (NQO)-1, was analyzed due to its anti-inflammatory activity, which was upregulated by PYEE treatment. Consequently, PYEE could be candidates for the prevention and treatment of periodontal diseases.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.327-335
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• 2021

The tendency of the current times require education to focus on convergence, and the same applies to the essence of ceramics and design base imagination and creativity. For effective integration, a wide range of experimentations is required both in terms of academic and methodic approaches. This study analyzes the [TeamTeam Class] curriculum, converging ceramics with design initiated in the second semester (autumn semester) of 2020. Through reference materials on ceramics and design convergence education, it was possible to classify the following 5 categories: Subject, Method, Management, space and communication. The aim of the study is to find resolutions to overcome existing issues and problems in search of more effective methods. Although this study is based on convergence education, [TeamTeam Class] at Kookmin University, I hope to extend it further to also consider education after COVID-19.

• Korean Journal of Materials Research
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• v.22 no.12
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• pp.689-695
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• 2012

We have examined the co-doping effects of 1/2 mol% NiO and 1/4 mol% $Cr_2O_3$ (Ni:Cr = 1:1) on the reaction, microstructure, and electrical properties, such as the bulk defects and the grain boundary properties, of ZnO-$Bi_2O_3-Sb_2O_3$ (ZBS; Sb/Bi = 0.5, 1.0, and 2.0) varistors. The sintering and electrical properties of Ni,Cr-doped ZBS, ZBS(NiCr) varistors were controlled using the Sb/Bi ratio. Pyrochlore ($Zn_2Bi_3Sb_3O_{14}$), ${\alpha}$-spinel ($Zn_7Sb_2O_{12}$), and ${\delta}-Bi_2O_3$ were detected for all of compositions. For the sample with Sb/Bi = 1.0, the Pyrochlore was decomposed and promoted densification at lower temperature by Ni rather than by Cr. A homogeneous microstructure was obtained for all of the samples affected by ${\alpha}$-spinel. The varistor characteristics were not dramatically improved (non-linear coefficient, ${\alpha}$ = 5~24), and seemed to form ${Zn_i}^{{\cdot}{\cdot}}$(0.17 eV) and ${V_o}^{\cdot}$(0.33 eV) as dominant defects. From impedance and modulus spectroscopy, the grain boundaries were found to have been divided into two types, i.e., one is tentatively assigned to ZnO/$Bi_2O_3$ (Ni,Cr)/ZnO (0.98 eV) and the other is assigned to a ZnO/ZnO (~1.5 eV) homojunction.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.428-432
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• 2011

차량 통신 네트워크(VANET, Vehicle Ad hoc NETwork)는 ITS(Intelligent Transport System)의 발전과 함께 운전자의 안전 및 교통 정보, 긴급 메시지 등과 같은 서비스를 실시간으로 가능하게 할 수 있는 차세대 네트워크 기술이다. 이러한 차량 통신 네트워크는 현재 IEEE P1609에서 정의하고 있으며, WAVE(Wireless Access Vehicular Environment)로 알려져 있다. WAVE는 차량에 설치된 OBU(Onboard Unit)와 주변시설에 설치된 RSU(Road Side Unit)을 통하여 통신하며, 차량 간 통신을 지원하는 V2V(Vehicle to Vehicle)와 차량과 주변시설과의 통신을 지원하는 V2I(Vehicle to Infrastructure)로 나뉘어져 있다. 하지만 WAVE에서 정의하고 있는 네트워크 서비스(IEEE P1609.4)는 OBU와 RSU 간의 네트워크 서비스에 초점을 맞추고 있기 때문에 전체 네트워크의 QoS를 보장하기에는 미흡한 상태이다. 따라서 본 논문에서는 차량 통신 네트워크에서 End-to-End 간의 QoS 보장을 위한 무선 메쉬 네트워크 기반의 라우팅 알고리즘을 제안한다. 제안하는 알고리즘은 무선 메쉬 네트워크 노드의 호스트 라우터 기능을 통하여 차량 노드와 이기종 간의 네트워크 서비스를 가능하게 하며, 무선 메쉬 네트워크의 다중 채널을 이용하여 데이터의 중요도에 따른 차등 서비스를 지원한다. ns-2를 이용한 시뮬레이션 결과 제안하는 알고리즘이 QoS를 보장함으로써 차량 통신 네트워크의 성능을 향상시킬 수 있음을 입증하였다.