• Title/Summary/Keyword: RoF

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AN EXPERIMENTAL STUDY ON THE EFFECT OF TOPICAL APPLICATION OF STANNOUS ELUORIDE TO THE STRIPPED ENAMEL SURFACE (불소가 삭제된 법랑질 표면에 주는 영향에 관한 실험적 연구)

  • Ro, Tae Rae
    • The korean journal of orthodontics
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    • v.2 no.1
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    • pp.23-28
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    • 1971
  • In this study, sections of twenty eight teeth were used to investigate the effect of topical application of $8\%$ stannous fluoride on the decalcification rate of enamel surfaces stripped in a manner suggested for orthodontic purpose. The enamel treated with a single application of a fluoride had a significantly lower tile rate of decalcification for the first 96 hours to lactate buffer solution. After double application of fluoride, decalcification rate decreased signicantly. This study suggested that the continuing protection of stripped surfaces should be sought by regularly scheduled treatment of the enamel with the topical application of fluoride and regular use of a fluoride containing dentifrice.

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The Ethnic Look Featured on Vivienne Tam's Collection from 1996 to 2005 (비비안 탐의 디자인에 나타난 민속풍에 관한 연구 - 1990년에서 2005년의 컬렉션을 중심으로 -)

  • Ro, Mi-Kyung;Kim, Chan-Ju
    • Journal of the Korean Society of Costume
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    • v.58 no.6
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    • pp.145-157
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    • 2008
  • Vivienne Tam was born in mainland China and educated in Hong Kong and has worked mainly in New York. Within multi-cultural background, she has shown unique fashion designs where western styles and China esprit were harmonized.. This study analyzed the ethnic look featured on Vivienne Tam's design to identify how she has expressed her ethnic identity into fashion. Photos featuring ethnic appeal among her New York collection from 1996 S/S to 2005 F/W were analyzed in terms of shape/silhouette, color, fabric, motifs, detail and accessaries. She utilized frequently chinese motifs and patterns such as bamboo, panda, budha, flowers, letters, and masks. Secondly she modified the shapes of Chinese traditional costume like Quipao to render ethnic appeal. Color, fabric and detail like frog and embroidery also contributed to enhance China mood. Comparatively, she used western clothing items including shirts, blouses, skirts, pants, dresses, and coats and maintained the silhouette tight and fit so that most her designs look wearable and westernized.

Experimental Study on Reinforcing Fiber for Civil Engineering used for Waterproofing Protection and Root Resistance Performance (방수보호재 및 방근재로서의 활용을 위한 토목용 보강섬유의 실험적 연구)

  • Kim, Bum Soo;Lee, Jung Hun;Song, Je Young;Song, Young-Chan;Kim, Yong-Ro;Oh, Sang Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.05a
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    • pp.67-68
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    • 2017
  • This paper discusses the application of civil structure use reinforcing fiber mixed with concrete to be used as protection layer of waterproofing material and root resistant layer installed in below-grade parking lot upper slab of residential building. A performance evaluation under the prescribed method outlined in KS F 4938 was used for this new material. The testing results showed that the fiber reinforcement can be used to strengthen the protection for the waterproofing material. Also, plants that were planted in June 2016 have not yet penetrated the specimens used for root resistance testing. The domestic root resistance performance testing usually covers the period of 2 years, thus further observation to make any conclusion about the root resistance property is required.

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Chemical Study on the Phenolic Compounds from Gleditsia japonica (주엽나무의 페놀성 성분에 관한 화학적 연구)

  • Hwang, Yoon-Jeong;Lee, Seung-Ho;Ryu, Shi-Yong;Ahn, Jong-Woong;Kim, Eun-Joo;Ro, Jai-Seup;Lee, Kyong-Soon
    • Korean Journal of Pharmacognosy
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    • v.25 no.1
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    • pp.11-19
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    • 1994
  • Gleditsia japonica var. koraiensis NAKAI(Leguminosae) is commonly distributed in Korea and has been used as a folk medicine in the treatment of bronchitis, neoplasm and blennorrhgia in the Orient. The aqueous acetone extract of the leaves of G. japonica was subjected to a combination of Sephadex LH-20, Cosmosil $75C_{18}-OPN$, TSK-gel Toyopearl HW 40F, Avicel cellulose, and MCI-gel CHP 20P chromatographies with various solvent systems. Twelve compounds were isolated and confirmed to be vitexin(1), isovitexin(2), orientin(3), isoorientin(4), 4-caffeoyl quinic acid(5), 5-caffeoyl quinic acid(6), 3, 5-dicaffeoyl quinic acid(7), 4, 5-dicaffeoyl quinic acid(8), caffeic acid(9), quercetin(10), isoquercitrin(11) and luteolin-7-O-glucoside(12), on the basis of chemical and spectroscopic evidences.

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A Study on the Practical lighting Guide for Night Work (야간작업 안전의 적정조명 기준설정을 위한 실험연구)

  • Ro Min-Lae;Son Ki-Sang
    • Journal of the Korean Society of Safety
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    • v.19 no.3 s.67
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    • pp.70-77
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    • 2004
  • A Reasonable lighting should be provided for doing night work. All works far construction site can be exposed to potential hazard at night work The purpose of this study is to provide a standard of the lighting against accidents due to insufficient lighting at site. one pilot tea one at building work site, one at mad work site of it have been conducted for figuring out illumination change depending worker's activity direction, using lux checker to show it as numerical indication. The direction are changed with a range of 30, 60, 90, and 135 degree to be checked at site. Tests results show that $10\%\;and\;15\%$ of lighting could be decreased by changing the working direction of works at site. Therefore, steep slope place, cave work and backside of structural elements such as a column, deep beam should be considered for keeping sufficient and reasonable lighting. It is found that $50\%more$ illumination Lux needs f3r civil work than for building work.

6-Methoxyluteolin from Chrysanthemum zawadskii var. latilobum Suppresses Histamine Release and Calcium Influx via Down-Regulation of $Fc{\varepsilon}RI$ ${\alpha}$ Chain Expression

  • Shim, Sun-Yup;Park, Jeong-Ro;Byun, Dae-Seok
    • Journal of Microbiology and Biotechnology
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    • v.22 no.5
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    • pp.622-627
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    • 2012
  • Mast cells and basophils are important effector cells in immunoglobulin-E (IgE)-mediated allergic reactions. Using the human basophilic KU812F cells, we assessed the inhibitory effects of 6-methoxyluteolin, isolated from Chrysanthemum zawadskii, in the $Fc{\varepsilon}RI$-mediated allergic reaction. We determined that 6-methoxyluteolin inhibited anti-$Fc{\varepsilon}RI$ ${\alpha}$ chain antibody (CRA-1)-induced histamine release, as well as elevation of intracellular calcium concentration $[Ca^{2+}]_i$ in a dose-dependent manner. Moreover, the inhibitory effects of 6-methoxyluteolin on the cell surface expression and the mRNA level of the $Fc{\varepsilon}RI$ ${\alpha}$ chain were determined by flow cytometric analysis and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Therefore, these results show that 6-methoxyluteolin is a potent inhibitor of histamine release and calcium influx via down-regulation of the $Fc{\varepsilon}RI$ ${\alpha}$ chain.

Low k Materials for High Frequency High Integration Modules (고주파대응 고집적 모듈용 저유전율 소재)

  • Na, Yoon-Soo;Hwang, Jong-Hee;Lim, Tae-Young;Shin, Hyo-Soon;Kim, Jong-Hee;Cho, Yong-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.328-328
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    • 2008
  • As a low K material for high frequency high integration modules, glass/ceramic composites were investigated. Glass composition were selected from $SiO_2-B_2O_3-Al_2O_3-R_2O$-RO system which having very low dielectric constant and cordierite was used as a ceramic filler. These composites were sintered at temperature range from $850^{\circ}$ to $950^{\circ}$ and XRD, SEM microstructure analysis of sintered bodies were performed for understanding sintering behavior. Any crystallization was not occurred and dense sintered bodies were attained. Dielectric and mechanical properties of these sintered glass/cordierite composites were analysed by network analyzer and UTM. Glass/ceramic composite with 50 wt% cordierite showing a dielectric constant (${\varepsilon}_r$) of 5.4, Q${\times}f_0$ (Q) of 1600 at 1 GHz and maximum bending strength of 163 MPa was attained.

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Static and Dynamic Characteristics of Magnetically Preloaded Air Bearing Stage for a 3-Axis Micro-Machine Tool (3축 마이크로 공작기계용 자기예압 공기베어링 스테이지의 정, 동적 특성)

  • Ro Seung-Kook;Ehmann Kornel F.;Yoon Hyung-Suk;Park Jong-Kweon
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2005.05a
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    • pp.468-472
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    • 2005
  • In this paper, the static and dynamic stiffness of the air bearing stage for micro-micro machine tool are examined experimentally. For stiffness and precision concerns, air bearing stages are adapted for 3-axis micro-milling machine which is size of $200x200\;mm^2$. The air bearings in the stage are preloaded by permanent magnets to achieve desired bearing clearance and stiffness for vertical direction. As the stiffness of the air bearing is primary interests, static stiffness test were performed on XY stage in Z direction and Z column in Y direction. Dynamic test were performed on XY stage and Z column, respectively. Both static and dynamic tests were performed in different air pressure conditions. The vertical stiffness of XY stage is about 9 N/ pm where Y stiffness of Z column is much smaller as $1\;N/{\mu}m$ because of the large moment generated by Y force on the column.

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Constructing Korean Dialogue Natural Inference Dataset through Pseudo Labeling (Pseudo Labeling을 통한 한국어 대화 추론 데이터셋 구축)

  • Young-Jun Lee;Chae-Gyun Lim;Yunsu Choi;Ji-Hui Lm;Ho-Jin Choi
    • Annual Conference on Human and Language Technology
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    • 2022.10a
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    • pp.205-209
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    • 2022
  • 페르소나 대화 시스템이 상대방의 개인화된 정보에 일관된 응답을 생성하는 것은 상당히 중요하며, 이를 해결하기 위해 최근에 많은 연구들이 활발히 이루어지고 있다. 그 중, PersonaChat 데이터셋에 대해 수반/중립/모순 관계를 라벨링한 DialoguNLI 데이터셋이 제안되었으며, 일관성 측정, 페르소나 속성 추론 태스크 등 여러 분야에 활용되고 있다. 그러나, 공개적으로 이용가능한 한국어로 된 대화 추론 데이터셋은 없다. 본 연구에서는 한국어로 번역된 페르소나 대화 데이터셋과 한국어 자연어 추론 데이터셋에 학습된 모델을 이용하여 한국어 대화 추론 데이터셋(KorDialogueNLI)를 구축한다. 또한, 사전학습된 언어모델을 학습하여 한국어 대화 추론 모델 베이스라인도 구축한다. 실험을 통해 정확도 및 F1 점수 평가 지표에서 KLUE-RoBERTa 모델을 미세조정(fine-tuning)시킨 모델이 가장 높은 성능을 달성하였다. 코드 및 데이터셋은 https://github.com/passing2961/KorDialogueNLI에 공개한다.

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Adsorption of Anionic Species on Clay Minerals (점토광물에 의한 음이온 화학종 흡착 특성)

  • Moon, Jeong-Ho;Choi, Choong-Ho;Ryu, Byong-Ro;Kim, Cheol-Gyu
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.10
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    • pp.1058-1064
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    • 2005
  • This research was designed to investigate the removal of anionic species, such as $F^-$, $Cl^-$ and ${NO_3}^-$, by adsorption on the clay minerals. Bentonite, $Ca^{2+}$ or $Na^+$ ion exchanged bentonite and montmorillonite, such as KSF and K10 from Sigma Aldrich, were used as the adsorbent. The component of five inorganic adsorbent was analyzed by XRF and XRD and the concentration of anion was measured by ion chromatography. From the experimental results, it was shown that the adsorption equilibrium was attained after 8-24 hours. For the amount of 6 g of each adsorbent, the adsorption capacities of $F^-$ and ${NO_3}^-$ on KSF was the largest as $825\;{\mu}g/g$ and $707\;{\mu}g/g$ respectively and that of $F^-$ on $Ca^{2+}$ ion exchanged bentonite was $255\;{\mu}g/g$ and that of ${NO_3}^-$ on K10 was $103\;{\mu}g/g$. In general, the efficiency of removal for the anionic species was increased with increasing of the amount of the adsorbent. Especially, for the amount of 6 g of KSF, the efficiency of removal for $F^-$ and ${NO_3}^-$ was 99% and 95% respectively. But, for all adsorbents, the efficiency of removal for $Cl^-$ was less than 9%. Also, a Freundlich equation was used to fit the acquired experimental data. As the result, for the $F^-$ and ${NO_3}^-$ on KSF, Freundlich constants, K, was respectively 1.09 and $0.45\;[mg/g][L/mg]^{1/n}$ and the adsorption intensity(1/n) was determined to be 0.08 and 0.27 respectively.