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A study on the electrical properties of lipid monolayers by displacement current method (변위전류법에 의한 지질단분자막의 전기특성에 관한 연구)

  • 이경섭;권영수
    • Electrical & Electronic Materials
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    • v.9 no.5
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    • pp.450-454
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    • 1996
  • Maxwell-Displacement-Current(MDC) measuring technique has been applied to the study of monolayers of Dilauroylphosphatidylcholine (L-.alpha.-DLPC) and Dimyristoylphosphatidylcholine (L-.alpha.-DMPC). The displacement current was generated from monolayers on a water surface by monolayer compression. Displacement current was generated when the area per molecule was about 250.angs.$^{2}$, 280.angs.$^{2}$. Displacement current was generated in the gas state, gas/liquid state, and liquid state in the course of monolayer compression. The orientational change of molecules in monolayers was discussed on the basis of the MDCs obtained. Finally, we measured differential thermal analysis of sample.

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Development of the Sintered Friction Material for the High Speed Railway (고속철도 차량용 소결 마찰재료 개발)

  • Kim Ki-Youl;Kim Sang-Ho;Kim Yu-Shin;Lee Beom-Joo;Kim Seog-Won
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.315-321
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    • 2004
  • Dawin Friction Corp. has been advanced sintered brake pad for Korean concept high speed train (so called G7 train) with KRRI, You Jin and Rotem without the assistance of foreign company. In the course of development, the evaluation of our and foreign disk pads was performed by lab scale dynamometer and full scale dynamometer. As the result of dynamo test, it is shown that our developed brake disk is equal or superior to those of foreign companies in many respects, for example, wear resistance, noise, etc. The new brake pad which is developed through 'post G7-project' is equipped with G7 train and is under many tests without any problems at the present moment.

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Synthesis of Three Ring Type Compounds with Fluorine and NCS Groups as Candidates for VA mode Liquid Crystal Display

  • Heo, E.Y.;Kim, Y.B.;Kim, S.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.571-574
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    • 2003
  • Three ring type liquid crystalline compounds having 4-alklycyclohexyl group, 1,2-difluorobenzene and phenylisothiocyanate moieties as main skeleton were designed to have negative dielectricity. However, the compounds with 2,3,2'-trifluoro-3'-isothiocyanated biphenylcyclohexane core did not exhibit the nematic liquid crystalline phase because of two conformers by interaction of isothiocyanate and adjacent fluorine atoms. Also, 4-alkyl-2,2',3'-trifluoro-3-isothiocyanated biphenylcyclohexane core was designed expecting to have uniform conformers of isothiocyanate group. In the course of developing polyimides for VA mode LCD, we synthesized alkyl-3,5-diaminobenzene efficiently with various length of alkyl chains from commercially available di-t-butyl malonate and 3,5-dinitrobenzoyl chloride as starting material.

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A Study on Fashion Designing Idea (의상디자인 발상법에 관한 연구)

  • 조진숙;한명숙
    • The Research Journal of the Costume Culture
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    • v.8 no.4
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    • pp.537-548
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    • 2000
  • This paper focuses on development of a fashion design education course that will foster the talent and aesthetic consciousness of fashion design student. The writer reached the content of the designing ideas to practical applications as the defined scope of fashion design education. For designing idea in practical application : matching ideas, contrasting ideas, formative combinations and revisionism were used. For design ideas, the ideas developed by 飯塚弘子, 万江入重子, 香川達子 were used in revision. To detail the content of design education, fashion magazines, portfolios, photographs and related fashion design educational materials were used. 1. Matching ideas : it proposes such identical expression into costume by making a research of developing material, application form and color extraction from design sources. 2. Contrasting ideas : it proposes such opposite expression into costume by making a research of opposite to image, form, position and purpose from some object. 3. Formative combinations : it proposes such new expression into costume by combining a detail of costume with the other object. 4. Revisionism : it proposes such modified expression into costume by making a research of deletion, change, addition and conversion in costume.

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A Study on the Expression of eroticism and Modern Costume -Surrealism, Pop Art, Post Modernism- (현대복식과 에로티시즘(Eroticism)적 표현에 관한 연구 -초현실주의, 팝아트, 포스트 모티니즘-)

  • 김명주;김분숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.4
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    • pp.460-472
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    • 1994
  • The Purpose of this study was to find in the art the basis of originality appeared on the fashion design and investigating the erotic expression appeared on the ornaments how art surrealism, pop art, post moderninism-formularize in the modern fashion. This study about the expression of eroticism and modren costume, through the source of pictures contained in art books and mode magazine and documents investingation has resulted as follows: First, the formality and contents that related art and fashion shows us a various aspect. That based on modeled characteristic and various technique of the art. Second, the expression of eroticism in fashion expressed differently in style, material and expression method that is more strongly, sometimes metaphorically with spirit of the time's. Third, the expression of eroticism in fashion whether direct way or symbolic way has appeared as partial exposure of the body. It is appearing to the course that can display individuality of each person over the taboo of the part and the previous limitation of fashion.

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Effects of Recycling on Adsorption Characteristics of Cationic Polyacrylamide onto Primary and Secondary Fines (리사이클링 횟수에 따른 일차미세섬유와 이차미세섬유의 폴리아크릴아미드 흡착특성 변화)

  • 주성범;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.2
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    • pp.34-41
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    • 1999
  • Adsorption of cationic polyacrylamide dry strength resins onto the surface of papermaking fibers and fines is critical for their effective utilization. Since dry strength resins are frequently employed when recycled fibers containing a great deal of fines are used as a raw material, their adsorption characteristic onto the recycled fiber fines is of great importance. In this study, effects of recycling on adsorption characteristics of cationic polyacrylamide onto primary and secondary fines were examined. Never dried bleached hardwood kraft pulp was beaten and dried for recycling. In each recycling step the adsorption characteristic of a cationic PAM onto primary and secondary fines was evaluated by kjeldahl nitrogen analysis method. The influence of recycling on water retention value and carboxyl content along with the sheet density and tensile strength was examined. Secondary fines of never dried pulp adsorbed twice as much of C-PAM as the primary fines, however, the adsorption capacity of the secondary fines decreased rapidly during the course of recycling and showed lower adsorption capacily than primary fines.

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Synthesis of barium hexaaluminate by sol - gel method (졸 - 겔법에 의한 바륨헥사알루미네이트 합성)

  • 백영순;김형진
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.5 no.2
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    • pp.142-151
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    • 1995
  • Complex alkoxides were synthesized using metal alkoxide method and were then hydrolyzed to prepare the precursors using sol - gel method. Then, the precursors were calcined in order to make barium hexaaluminate. Factors affecting the material properties of the barium hexaaluminate precursors were studied and they are the kinds and amount of alcohols, and reaction time. In addition, in the course of hydrolysis, the effects of the amount of water, reaction temperature and aging time were also studied in terms of the specific surface area and average particle size of the barium hexaaluminates.

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A Study of Improvement on Collaboration Treatment Method of Electroplating Wastewater (도금폐수의 공동처리를 위한 공정개선에 관한 연구)

  • 이내우;최재욱;안병환
    • Journal of the Korean Society of Safety
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    • v.12 no.4
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    • pp.93-101
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    • 1997
  • A modified procedure for electroplating wastewater treatment using formaldehyde and hydrogen peroxide can destroy free cyanide. The representative diagram which is quite sensitive on reaction temperature is showed for this kinds of treatment. Principally free cyanide and some kinds of cyanide complex should be treated first, and then toxic heavy metals can be removed because cyanide component will be inhibited to remove other pollutants, if it is not destroyed perfectly. Formaldehyde and hydrogen peroxide are added in controlled amounts to cyanide treatment tank. Reasonable amounts of these chemicals are (HCHO/CN)=0.9 and ($H_2O_2/CN$)=1.1 in molar ratios, it is also variable on reaction temperature. Of course, actual treatment processes depending on plating material and chemical are good applicable, also to systematize operation manual for treating electroplating wastewater process, further works are desirable.

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Analysis on the Mechanism of Fluting in the Bending of Low Carbon Steels (저탄소강판을 이용한 굽힘 가공에서 발생하는 꺾임 현상에 대한 발생기구 해석)

  • Park, K.C.;Yoon, J.B.
    • Transactions of Materials Processing
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    • v.16 no.4 s.94
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    • pp.317-322
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    • 2007
  • In order to investigate the cause and condition of fluting in tangential bending of low carbon steel sheet, an analytic analysis, an experiment and a series of finite element analysis for bending process were done. The fluting in bended sheet was related with the yield point elongation of material. Due to the yield point elongation, unstable plastic hinge was occurred in course of bending of elastic perfectly plastic sheet. According to the analysis and computational results, lower yield point elongation than 5% was required to prevent fluting in 0.5-0.6t sheet in $15{\sim}25mm$ radius bending. The tendency of fluting occurrence was reduced as decreasing the radius of bending, increasing thickness of bended sheet, and removing irregularity in sheet and bending processes.

The change of matter properties of paper cultural heritage by wet cleaning (습식크리닝에 의한 지류문화재의 물성변화)

  • Cheon, Ju-hyun;Jang, Eun-ji
    • Conservation Science in Museum
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    • v.6
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    • pp.73-83
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    • 2005
  • To understand the influence of wet cleaning performed in the course of preserving paper items, the change of matter properties by before and after wet cleaning was observed. Specifically, structural and optical qualities and strength were measured. The result showed that wet cleaning caused a substance change in the paper items and particularly weakened the structure material of pigments, Chinese ink, dyes, etc.