• Title/Summary/Keyword: the property (H)

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Stabilization of the luminance efficiency in the blue organic light-emitting devices utilizing CBP and DPVBi emitting layers

  • Bang, H.S.;Choo, D.C.;Park, J.H.;Seo, J.H.;Kim, Y.K.;Kim, T.W.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1454-1456
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    • 2007
  • The electrical and the optical properties of blue organic light-emitting devices (OLEDs) with a multiple emitting layer (EML) acting as electron and hole trapping layers were investigated. While the luminance efficiency of the OLEDs with a multiple EML was very stable, regardless of variations in the applied voltage.

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Measurement Techniques of Mechanical Properties for Development of Nano Fabrication Process (나노 공정 개발을 위한 기계적 물성 측정 기법)

  • Lee, H.J.;Choi, B.I.;Kim, W.D.;Oh, C.S.;Han, S.W.;Hur, S.;Kim, J.H.;Ko, S.G.;Ahn, H.G.
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1104-1110
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    • 2003
  • There are many applications of nanostructures, have been suggested by lots of researchers. It is highly required to measure the properties of nano-sized materials for design and fabrication of the nanostructures. In this paper, several techniques for measuring the mechanical properties of nano-structures are presented laying emphasis on the activity of Nano Property Measurement Team in KIMM. Some advanced applications of nano-indenter are described for measuring elastic, visco-elastic, frictional and adhesive properties as well as the standard methods of it. Micro-tensile test technique with accurate in-plane strain measurement method is also presented and its role in the property measurement of nanostructures is discussed.

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Evaluation of the Physical and the Mechanical Properties of the High Frictional Resistance Prepreg and the Low Frictional Resistance Prepreg (고마찰저항 프리프레그와 저마찰저항 프리프레그의 물리적 및 기계적 특성평가)

  • Kim, Y.H.;Han, J.W.;Kim, K.J.;Kim, J.H.;Son, J.H.
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.326-330
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    • 2005
  • Aircraft composite structure with honeycomb core experiences core crush problem in manufacturing. To prevent core crush additional processes are needed such as core stabilization and prepreg material tie-down and this is the cause of increasing cost. Recent study shows that high friction prepreg prevent core crush without additional process. This paper presents the analysis of high frictional material which attracts lots of interests through physical property, mechanical property and microscopic

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The Fabrication of $MgB_{2}$ superconducting tape and its transport critical current property under magnetic field (Mg $B_{2}$초전도 선재 제조 및 자장하에서의 임계전류특성)

  • J-W Ko;J.M. Yoo;Y.K. Kim;K-H Oh;S.J. Choi;H.S. Chung;H. Kumakura;K. Togano
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.3-4
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    • 2002
  • The stainless steel sheathed MgB$_2$ tapes with Cu addition were fabricated by PIT method without heat treatment. The $J_{c}$ value of 5,600 A/ $cm^{2}$and 16,000 A/$cm^{2}$ at 4.2 K and 5 T were obtained for the $MgB_{2}$ tape and 10 vol % of Cu added $MgB_{2}$ tape respectively. The $J_{c}$-B curve shows enhancement in J$_{c}$ under magnetic field, which suggests enhancement in flux pinning property with Cu addition.n.

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Control of Catalytic Properties of Heteropoly Acid by Blending it with a Polymer (고분자와의 블랜딩에 의한 헤테로폴리산의 촉매 특성 제어)

  • Song, In Kyu;Lee, Jong Koog;Lee, Wha Young
    • Applied Chemistry for Engineering
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    • v.5 no.5
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    • pp.819-824
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    • 1994
  • A membrane-like $H_3PMo_{12}O_{40}$-polysulfone film was prepared by blending $H_3PMo_{12}O_{40}$ with polysulfone using dimethylformamide as a common solvent. SEM and EDX analysis showed that $H_3PMo_{12}O_{40}$ was uniformly and finely distributed in the film catalyst. The ESCA measurement also revealed that the oxidation state of Mo was not changed. The $H_3PMo_{12}O_{40}$-polysulfone catalyst showed lower activity for acid-catalyzed reaction and higher activity for oxidation reaction than $H_3PMo_{12}O_{40}$ in ethanol conversion reaction. The oxidation activity of the film catalyst was about 10 times higher than $H_3PMo_{12}O_{40}$. The decrease of acidic activity was due to DMF strongly adsorbed in acid sites of $H_3PMo_{12}O_{40}$, whereas the increase of oxidation activity was mainly due to uniform distribution of $H_3PMo_{12}O_{40}$. Adsorption results showed that the surface character of $H_3PMo_{12}O_{40}$ was drastically increased, while the bulk property of that was almost same after blending. It is suggested that the control of surface/bulk property as well as acid/redox property of heteropoly acid would be possible by blending it with a polymer.

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Determination of the effective spray- interval of Bacillus thuringiensis against diamond-back moth (Plutella xylostella) on chinese cabbage

  • Han, E.J.;Park, J.H.;Hong, S.J.;Ahn, N.H.;Jee, H.J.;Kim, Y.K.
    • Korean Journal of Organic Agriculture
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    • v.19 no.spc
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    • pp.259-262
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    • 2011
  • In organic Chinese cabbage fields, Commercial Bacillus thuringiensis products are used widely against diamond back moth, Plutella xylostella. We conducted the study to determine the effective spray-interval of commercialized B. thuringiensis against diamond back moth on Chinese cabbages. Chinese cabbage leaves were collected 0, 1, 2, 3, 6, 10days after treatment in first trial and 0, 2, 4, 7, 9, 11days after treatment. We compared the insecticidal property of sprayed B. thuringiensis and the density of it on surface of Chinese cabbages using collected leaves. The insecticidal property maintained high until nine days after commercial B. thuringiensis products sprayed.

Metamaterial Perfect Absorber Technology for Leading the Fourth Industrial Revolution (4차 산업혁명을 선도할 메타물질 완전흡수체 기술 동향)

  • Hong, S.H.;Kim, M.H.;Yun, H.W.
    • Electronics and Telecommunications Trends
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    • v.32 no.6
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    • pp.1-7
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    • 2017
  • A metamaterial is a material engineered to have a property that does not exist in nature. A designable material property can be achieved by tailoring its structure, and thus a metamaterial is a novel ICT material and component technology that can break through the limitations of conventional technologies. Among the metamaterials available, a perfect metamaterial absorber is a technology that can nearly absorb light, sound waves, thermal waves, and electromagnetic waves with a simple structure, and has been of significant interest in energy, display, sensor, stealth, and military applications, with wavelengths from visible light to microwaves. In this article, we introduce a brief description of metamaterial absorber technology, the critical issues for its application, as well as ETRI's developed metamaterial absorber technology and its prospects for future use.

The Electrocatalytic Reduction of Molecular Oxygen with Clay Modified Electrodes (점토광물을 이용한 산소환원의 전기화학적 촉매성에 관한 연구)

  • Oh Sung-Hun;Hwang Jin-Yeon;Shim Yoon-Bo;Lee Hyomin;Yoon Jihae
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.1
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    • pp.1-9
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    • 2005
  • The electrocatalytic reduction of O₂ was investigated with methyl viologen and methylene blue incorporated clay-modified electrodes. Clay suspensions were prepared with Na-montmorillonite, Ca-montmorillonite, and kaolinite. The methyl viologen-clay modified electrodes were made by coating clay suspensions adsorbing methyl viologen on a glassy carbon electrode. Cyclic voltammetry were performed in aqueous media to investigate the electrocatalytic property of the modified electrode in reducing O₂. A Na-montmorillonite modified electrode showed the greatest adsorption capacity for methyl viologen. The modified electrode made of Na-montmorillonite suspension of 0.87 g/10 mL and a 2.5 mM of methyl viologen solution showed the most effective electrocatalytic property, where the catalytic reduction potential was shifted by 242.6 mV toward the positive potential. The electrocatalytic ability was more significant in acidic (pH=3.7) and alkaline (pH=12.7) media than the neutral pH range (6.3∼8.3). The methyl viologen-Na-montmorillonite modified electrode had the good reproducibility and maintain the electrocatalytic property over 20 times reuse.

An Analysis on the Priority of Educational Needs of Teachers in Charge of Educational Contents of Invention Intellectual Property in Secondary Vocational Education (중등단계 직업교육에서의 발명·지식재산 교육내용에 대한 담당 교사의 교육요구도 우선 순위 분석)

  • Lee, Sang-hyun;Lee, Chan-joo;Lee, Byung-Wook
    • 대한공업교육학회지
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    • v.40 no.2
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    • pp.155-174
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    • 2015
  • The purposes of this study were to analyze the property of educational needs of teachers for educational contents of invention and intellectual property in secondary vocational education and provide fundamental data for the development of job training programs so as to develop the capabilities of teachers, the base for effective education of invention intellectual property in secondary vocational education. To achieve them, educational needs for the educational contents of invention intellectual property and the priority of the educational needs in secondary vocational education based on the recognition of the teachers were analyzed and suggested. Concrete results of this study can be suggested as follows. First, the average of educational needs of the teachers for the educational contents of invention intellectual property in secondary vocational education was 5.02. There were 23 items of the educational contents whose educational needs were higher than the average of the whole items and for those items and the average of each item, there were F4(The average of patent applications) 6.72, F5(Modification and supplementation of specification sheets) 6.46, F2(Writing of patent floor plans) 6.39, F3(Writing of patent specification sheets and abstraction) 6.31, A5(Invention method and activity) 6.27, E6(Invention design project) 6.15, H3(Invention commercialization) 5.97, F1(Patent information and application) 5.90, E5(Design obligation) 5.78, E3(Designing process of inventional design) 5.77, A4(Invention and problem solving) 5.57, G2(Patent investigation and classification) 5.47, C2(Thinking method of inventional problem solution) 5.45, E4(Production of inventional design product) 5.45, B5(Inventional patent project) 5.42, A2(Creativity development) 5.26, C4(Inventional problem solving project) 5.26, H4(Invention marketing) 5.26, H2(Analysis on invention commercialization) 5.20, D4(Invention and management) 5.16, C3(Problem solving activity) 5.14, E2(Inventional design devise and expression) 5.11, B3(Actuality of inventional method) 5.08 in order. Second, for the priority of educational needs of the teachers for the educational contents of invention intellectual property in secondary vocational education, there were 13 items of the educational contents for the first rank, 10 for the second rank and 17 for the third rank. The items of the educational contents for the first rank were A4(invention and problem solving), A5(inventional method and activity), B5(Invention patent project), C2(Thinking method of inventional problem solution), C4(Inventional problem solving project), E3(Inventional design process), E4(Production of inventional design product), E5(Design obligation), E6(Invention design project), F1(Patent information and application), F2(Writing of patent floor plan), F3(Writing of patent specification sheet and abstract), and H3(Invention commercialization. The items of the educational contents for the second rank were A2(Creativity development), B3(Actuality of inventional method), C3(Problem solving activity), D4(Invention and management), E2(Invention design devise and expression), F4(Range of patent demand), F5(Modification and supplementation of specification sheet), G2(Patent investigation and classification), H2(Analysis on invention commercialization), and H4(Invention marketing). The items for the third rank were the educational contents except the ones of the first rank and the second rank.

Characterization of colloid/interface properties between clay and EAF dust (점토와 전기로 제강분진의 콜로이드/계면 특성 분석)

  • Lee, Jee-Young;Lee, Ki-Gang;Kim, Yoo-Taek;Kang, Seung-Gu;Kim, Jung-Hwan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.16 no.2
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    • pp.76-81
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    • 2006
  • The leaching behavior of heavy metal ions with pH and colloid/interface property was analyzed by ICP and SEM. The heavy metals in EAF dust are 'amphoteric metal' and the heavy metal ions leached a little at pH 10. And the leaching concentrations of heavy metals at pH 12 were higher than the that at pH 8. The leaching concentrations of heavy metal ion were decreased with adding the clay to the EAF dust. Especially, the leaching concentrations of heavy metal ion were effectively decreased at pH 12. The observation of colloid/interface properties shows that the soluble silicon hydroxide from clay at pH 12 was precipitated at the surface of the heavy metal and clay particles. This silicon hydroxide precipitates were named the PSHP. The leaching concentrations of heavy metal ion were effectively decreased by the formation of PSHP when adding the clay to the EAF dust and controlling the pH of the slurry at 12.