• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.23-30
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• 2021

Hemistepta lyrata Bunge (HL) has been used as a folk remedy to treat cancer, inflammation, bleeding, hemorrhoids and fever, and leaves and young shoots have been used as famine food. Nevertheless, the biological activities and underlying mechanisms of the anti-inflammatory effects remain unclear. In this study, it was undertaken to explore the functions of the aerial part of HL as a suppressor of inflammation by using RAW 264.7 cells. As immune response parameters, the productions of as nitric oxide (NO) and prostaglandin E2 (PGE2), cytokines such tumor necrotic factor (TNF)-α and interleukin (IL)-6 were evaluated. Although the release of TNF-α remained unchanged in HL-treated RAW 264.7 cells, the productions of NO, PGE2 and IL-6 were significantly increased at concentrations with no cytotoxicity. Furthermore, HL significantly attenuated the mitogen-activated protein kinases (MAPK) pathway including decreasing the phosphorylation of the extracellular signal-regulated kinase (ERK1/2) and p38 mitogen-activated protein kinases. Collectively, this study provides evidence that HL inhibits the production of major pro-inflammatory molecules in LPS-stimulated RAW 264.7 cells via suppression of ERK and P38 MAPK signaling pathways. These findings suggest that the beneficial therapeutic effects of HL may be attributed partly to its ability to modulate immune functions in macrophages.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.311-311
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• 2011

$TiN{\times}$박막은 우수한 내마모성 및 내부식성, 높은 경도 그리고 열적 안정성 등으로 인하여, 절삭공구 및 기계적 부품의 하드코팅, 2차 연료 전지용 확산방지막의 코팅재료로서 광범위하게 사용되어지고 있다. 일반적으로 $TiN{\times}$ 박막은 화학 기상 증착법(CVD)을 이용하였으나, 최근에는 대면적에 균일한 코팅이 가능하고 기판과 박막상의 부착력이 우수하며, 프로세스를 제어하기 쉬운 물리적 기상 증착법(PVD)의 스퍼터링법에 대한 관심이 고조되고 있다. 그러나 스퍼터링법으로 증착된 $TiN{\times}$ 박막의 물성은 주상구조와 국부적 표면결함을 포함하는 박막의 미세구조에 의존하기 때문에 주상구조 사이에 존재하는 Void 와 Pinhole 그리고 crack들이 원인으로 작용하여, 내부식성 및 기계적 특성이 급속도로 저하되는 단점이 있다. 이러한 단점을 보완하기 위해서, 본 연구에서는 기판온도를(RT, $200^{\circ}C$, $400^{\circ}C$)증가시켜 실험 하였다. 이는 온도증가에 따른 박막의 치밀화가 이루어지고 결함이 감소하여 내부식성 특성향상이 기대되어진다. 또한 플라즈마 밀도를 높이기 위해서, 기존 DC 마그네트론 스퍼터링법에 전자기장을 추가로 인가하였다. 이는 플라즈마 밀도증가에 따른 고반응성의 질소 래디컬의 생성율 증가에 기인하여 박막 형성시 질화반응을 촉진시킴으로써 박막의 치밀화 및 내부식성 특성향상이 기대되어진다.

• Fire Science and Engineering
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• v.25 no.6
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• pp.156-167
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• 2011

The number of buildings is growing at a rapid pace in Korea. It is driven by significant economic improvements, the rapid population growth and urban centralization. Such being this case, some city are underway to building enlargement, Manhattanization. To Solve these problem and ensure the safety of live, fire Evacuation Simulation system is used for safe check of buildings. Forecasting an egress behavior in building fire is so important in order to construct a safe and reliable environment. But, currently most of the fire evacuation simulation system used in practice are foreign software that is not reflect korean conditions. Thus, This study focus on objectives that develop a fire evacuation system considering Korean Characteristics and create 3D space-based topology. so the system calculate evacuation path. This system developed as a result of research can be used by architectural designer in practice due to it is based 3D spatial information modeling.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.345-350
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• 1992

Proton lineshapes and chemical shifts of paramagnetic solutions of Ln$(NO_3)_3$ in DMF have been measured over the temperature range 240K to 3807K. Solvation sphere exchange rates and the thermodynamic exchange parameters for CHO group of the DMF molecules have been extracted from these data. The results were established through a detailed analysis and discussion of the temperature depending data of the 1/$T_2$ and ${\Dellta}{\omega}$ data were analyzed in detail, and it has been found that delocalization of the unpaired electron spin from some $Ln^{3+}$ ion to DMF molecules beyond the first solvation shell would occur, giving rise to a scalar relaxation contribution in the bulk solvent.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.72-75
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• 2010

Google을 시작으로 포털 사이트들이 Maps API를 공개하면서 맵 응용에 대한 수요가 급증하고 있다. 맵 응용의 개발은 대부분 수작업으로 이루어지고 있기 때문에 맵 응용의 생산성이 떨어질 뿐만 아니라 유지 보수에도 많은 시간과 노력이 요구되고 있다. 우리가 설계하고 구현한 MapAppGen은 ModuleGen, IndexGen, MapGen으로 구성되며 맵 응용을 자동으로 생성한다. MapAppGen은 Google Maps API를 사용하여 CMS(Content Management System) 중의 하나인 Drupal에 적용 가능한 모듈들을 생성해 맵 응용에 대한 생산성을 향상시켜 준다. MapAppGen처럼 맵 응용을 위해 Drupal 모듈을 생성하는 생성기는 현재 존재하지 않으며 Gmap이나 NodeMap과 같이 고정된 맵 인터페이스 모듈들은 존재한다. 그러나 Gmap이나 NodeMap 모듈은 Drupal의 기본 컨텐츠 타입 모듈에 의존하기 때문에 사용자는 원하는 지형/지물 컨텐츠 타입을 생성해 활용할 수 없고 지형/지물들을 유형별로 맵 상에 표시하고 연관된 컨텐츠들을 검색할 수도 없다.

• Journal of The Korean Association For Science Education
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• v.38 no.5
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• pp.721-738
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• 2018

Nature of Science(NOS) has been a well-organized focus of science education and one of the key elements in defining and cultivating scientific literacy for more than a century. In recent years, a specific description of NOS, which is often known as 'the consensus view of NOS', has become very influential and has gained ready acceptance as an arrangement for both curriculum building and research into understanding of NOS by students and teachers in many countries around the world. This study has two purposes; one is to review some debates and criticism on the consensus view of NOS which consists of a list of sentences to describe nature of refined and general science, which have been heated up for the last few years by many prominent science education researchers, and the other is to consider alternative perspectives on NOS for the purpose of a new direction of NOS education. As a result of an investigation into such views as 'Teaching about NOS', 'Critical NOS', 'Critical Thinking-NOS', 'Whole Science', 'Features of Science' and 'Reconceptualized Family Resemblance Approach to NOS', some implications which focus on the generality and plurality of content knowledge of NOS based on current philosophy of science and sociology of scientific knowledge are suggested for the improvement of teaching and learning NOS.

• Korean Journal of Social Welfare
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• v.67 no.2
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• pp.203-236
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• 2015

Given the interdependence of a marital couple, this study examined the effects of both cultural challenge and economic hardship on intention to divorce among the multicultural couple using the actor-partner interdependence model(APIM), and explored dyadic patterns of actor and partner effects. 415 couples(n=830) participated in this self-administered questionnaire study. Results of path analyses based on APIMs revealed that for Korean husbands perceived cultural challenge contributed positively to divorce intention of the couple showing both actor and partner effects, whereas for immigrant wives such perception showed only an actor effect. In contrast, perceived economic hardship among the husbands had little effect on divorce intention of both husbands and wives, whereas such perception by wives had both actor and partner effects on divorce intention. Results of dyadic pattern analyses performed by Bootstrap indicated the actor-only pattern and the couple pattern of perceived cultural challenge on divorce intention of husbands and wives respectively. In case of perceived economic hardship comparison of the effect size suggested the partner-only pattern and the actor-only pattern for divorce intention of husbands and wives respectively. These findings implied that in order to promote conjugal harmony and to prevent the multicultural family from being dissolved, Korean husbands need to develop greater cultural competence so as to tolerate cultural differences between the couple, whereas immigrant wives and their families need to develop greater economic competence so as to foster a hope for economic reliance.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.52-66
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• 2001

Background : NF-${\kappa}B$ is the most important transcriptional factor in IL-8 gene expression. Triptolide is a new compound that recently has been shown to inhibit NF-${\kappa}B$ activation. The purpose of this study is to investigate how triptolide inhibits NF-${\kappa}B$-dependent IL-8 gene transcription in lung epithelial cells and to pilot the potential for the clinical application of triptolide in inflammatory lung diseases. Methods : A549 cells were used and triptolide was provided from Pharmagenesis Company (Palo Alto, CA). In order to examine NF-${\kappa}B$-dependent IL-8 transcriptional activity, we established stable A549 IL-8-NF-${\kappa}B$-luc. cells and performed luciferase assays. IL-8 gene expression was measured by RT-PCR and ELISA. A Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation and an electromobility shift assay was done to analyze NF-${\kappa}B$ DNA binding. p65 specific transactivation was analyzed by a cotransfection study using a Gal4-p65 fusion protein expression system. To investigate the involvement of transcriptional coactivators, we perfomed a transfection study with CBP and SRC-1 expression vectors. Results : We observed that triptolide significantly suppresses NF-${\kappa}B$-dependent IL-8 transcriptional activity induced by IL-$1{\beta}$ and PMA. RT-PCR showed that triptolide represses both IL-$1{\beta}$ and PMA-induced IL-8 mRNA expression and ELISA confirmed this triptolide-mediated IL-8 suppression at the protein level. However, triptolide did not affect $I{\kappa}B{\alpha}$ degradation and NF-$_{\kappa}B$ DNA binding. In a p65-specific transactivation study, triptolide significantly suppressed Gal4-p65T Al and Gal4-p65T A2 activity suggesting that triptolide inhibits NF-${\kappa}B$ activation by inhibiting p65 transactivation. However, this triptolide-mediated inhibition of p65 transactivation was not rescued by the overexpression of CBP or SRC-1, thereby excluding the role of transcriptional coactivators. Conclusions : Triptolide is a new compound that inhibits NF-${\kappa}B$-dependent IL-8 transcriptional activation by inhibiting p65 transactivation, but not by an $I{\kappa}B{\alpha}$-dependent mechanism. This suggests that triptolide may have a therapeutic potential for inflammatory lung diseases.

• Composites Research
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• v.30 no.2
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• pp.84-93
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• 2017

This study investigates thermal and mechanical characterization of environmental barrier coating on the $SiC_f-SiC$ composites. The spherical environmental barrier coating (EBC) powders are prepared using a spray drying process for flowing easily during coating process. The powders consisting of mullite and 12 wt% of Ytterbium silicate are air plasma sprayed on the Si bondcoat on the LSI SiC fiber reinforced SiC composite substrate for protecting the composites from oxidation and water vapor reaction. We vary the process parameter of spray distance during air plasma spray of powders, 100, 120 and 140 mm. After that, we performed the thermal durability tests by thermal annealing test at $1100^{\circ}C$ for 100hr and thermal shock test from $1200^{\circ}C$ for 3000 cycles. As a result, the interface delamination of EBC never occur during thermal durability tests while stable cracks are prominent on the coating layer. The crack density and crack length depend on the spray distance during coating. The post indentation test indicates thermal tests influence on the indentation load-displacement mechanical behavior.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.56-56
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• 2017

점적 호스 중 PC 드립은 경질 호스의 내부에 Micro-path가 부착된 유로장치와 압력을 보상하는 연질의 실리콘으로 구성되어 있다. 이때 일정압력에서 적정 길이까지 동시에 내부 압력을 유지하며 균등하게 유출구를 통하여 유량을 공급하는 압력보상 기능이 매우 중요하다. 그러나 이 부분에 대한 기술은 선진국에 비해 아직 부족하여 수입에 의존하는 경향이 매우 높다. 뿐만 아니라 선진국 제품에 비해 유로장치 및 연질 실리콘의 탄성이 균일하지 못해 압력에 따른 유량의 편차가 큰 편이다. 본 연구에서는 우리나라 제품의 PC 드립 압력 균등성 기술을 향상시키기 위해 PC 드립의 핵심기술인 연질 실리콘의 성능에 대한 평가와 유량의 편차를 분석하여 문제점을 통한 개선방안을 제시하고자 하였다. 연질 실리콘의 규격은 $17{\times}8{\times}0.85mm$ (가로${\times}$세로${\times}$두께)로서 Water line의 내부에 결합되어 구성된다. PC 드립용 실리콘은 국내 A사 제품을 중심으로 하여 성능을 측정하였다. 측정을 정밀하게 하기 위해 Microtester를 사용하여 일정하게 하중이 부과되도록 하였다. 연질의 실리콘의 경도는 압력 보상에 중요한 기능을 하고 있으며 또한 PC 드립의 경질 미로와 같이 압력을 제어하는 역할을 하고 있다. 국내 A사의 실리콘 경도는 이상적인 실리콘 경도에 비하면 매우 불균일하였다. 세부적으로는 40 이하의 낮은 경도에서는 비교적 일치하였으나 경도 45 이상에서는 큰 차이를 보여주고 있었다. 국내 A사의 실리콘 경도에 따른 공급유량의 특성에서는 실리콘의 경도가 낮을수록 실리콘은 무르며 탄성이 줄어든다. 반면에 경도가 높을수록 탄성이 커지고 딱딱한 특성을 가진다. 동일한 PC 드립에 실리콘의 경도별 특성은 경도에 따른 유량이 반드시 일정하지 않으며 대체로 경도가 높을수록 동일 압력에 대해 유량이 많아지는 것을 알 수 있었다. 압력의 변화에 대해 유량이 일정하게 유지하는 특성을 가질수록 사용범위가 넓어지고 안정성이 높은 것으로 판단되며 실리콘 경도 35~55 범위에서 1~2bar의 공급압력에서 사용하는 것이 적합할 것으로 보여진다. 경도 45의 실리콘을 사용하여 수입 드립, 국내 A사의 드립 및 수입과 국내 혼용시 압력에 따른 공급유량의 특성을 분석하였다. 최대 유량과 최소 유량에서 발생되는 오차는 수입 실리콘이 비교적 작았으나 3.6 bar 이상에서는 유량이 급격히 떨어지는 양상을 보였다. 국내 A사의 제품은 0.8~2.0 bar 까지 성능이 비슷했으나 0.8 bar 이하에서는 오차가 있었으나 높은 압력에서는 오히려 성능이 우수하였다. 수입 드립과 다소 유사한 성능을 나타낸 것이 A사 드립과 수입 실리콘을 혼용하여 사용한 것은 전체적으로 비슷한 양상을 나타내었다. 따라서 실리콘 경도 오차를 고려하면 압력별 유량의 변화는 실리콘의 경도와 밀접한 관계가 있는 것으로 판단되었다.