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Effect of thermo-mechanical treatment on fabrication of Ag tapes for YBCO coated conductor (차세대 선재 기판용 Ag 테이프의 제조공정에서 가공 열처리가 집합조직에 미치는 영향)

  • Lee, N.J.;Oh, S.S.;Park, C.;Song, K.J.;Ha, D.W.;Kwon, Y.K.;Ryu, K.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.04a
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    • pp.46-49
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    • 2002
  • The aim of this paper is to investigate the influence of various deformation ratio on texture of Ag tapes that can be used as a RE-$Ba_2Cu_3O_{7-{\delta}}$ coated conductor tapes without any buffer layer. We fabricated as-rolled Ag substrate with various deformation ratio per step. Thickness and total deformation ratio of Ag tapes were $100{\mu}m$ and >98%, respectively. And as-rolled Ag substrate was annealed at $750^{\circ}C$ for 30min. The as-rolled and recrystallization textures were measured using x-ray pole figures and orientation distribution function (ODF) analysis. With the increase of rolling ratio from 5 to 20%, deformation texture are changed from {1l0}<311> to {1l0}<112>, {032}<100>, {051}<211>. After recrystallization by annealing, main texture was observed to {013}<100> under present condition.

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Size Tunable Nano Patterns Using Nanosphere Lithography with Ashing and Annealing Effect (나노 구체 리소그라피법에 Ashing과 Annealing 효과를 적용하여 크기조절 가능한 나노패턴의 제조)

  • Lee, Yu-Rim;Alam, Mahbub;Kim, Jin-Yeol;Jung, Woo-Gwang;Kim, Sung-Dai
    • Korean Journal of Materials Research
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    • v.20 no.10
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    • pp.550-554
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    • 2010
  • This work presents a fabrication procedure to make large-area, size-tunable, periodically different shape metal arrays using nanosphere lithography (NSL) combined with ashing and annealing. A polystyrene (PS, 580 ${\mu}m$) monolayer, which was used as a mask, was obtained with a mixed solution of PS in methanol by multi-step spin coating. The mask morphology was changed by oxygen RIE (Reactive Ion Etching) ashing and temperature processing by microwave heating. The Au or Pt deposition resulted in size tunable nano patterns with different morphologies such as hole and dots. These processes allow outstanding control of the size and morphology of the particles. Various sizes of hole patterns were obtained by reducing the size of the PS sphere through the ashing process, and by increasing the size of the PS sphere through annealing treatment, which resulted in tcontrolling the size of the metallic nanoparticles from 30 nm to 230 nm.

Effect of Controlled Atmosphere and Modified Atmosphere Storage on the Color and Sensual Properties of Fresh and Red Ginseng (CA 및 MA저장이 수삼 및 홍삼의 색상 및 관능적 특성에 미치는 영향)

  • 전병선;박채규
    • Journal of Ginseng Research
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    • v.22 no.2
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    • pp.82-90
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    • 1998
  • In order to stabilize the price of fresh ginseng by extension of seasonal variation and marketing structure, and to reduce the cost of production by works of intensive and short term, studies were carried out. As fresh ginseng of 4 years old by the MA and CA was stored for 12 week at 4$^{\circ}C$, samples were collected after every 1, 2, 3, 4, 6, 8, 12 weeks for processing red ginseng. Color and Sensual characteristics on ginseng steamed red for the quality evaluation are summarized as follows. For the time course of storage with red ginseng, which was processed from fresh one after various treatments, L and b values were decreased, however a value was increased. In particular, absorbance was step-wisely increased. Turbidity was somewhat increased, and non-treatment of preservative were shown 2 times higher of absorbance. Extraction ratio of ethanol-soluble extractives slightly increased by the preservation methods, and as storage period was passed. CA storage and preservative treat merit versus MA and non-preservative treatment gave much stability in ginseng quality. In the sensual characters, sour taste and sweet taste were increased, but fresh taste and rice scorched taste were decreased. Bitter taste was not much changed until end of storage. CA was shown smaller differences than MA in the pH change. Addition of preservative extended the storage time.

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Sharing Product Data among Heterogeneous PDM Systems Using OpenPDM (서로 다른 PDM 시스템 간에 OpenPDM을 이용한 제품데이터의 교환)

  • Yang, Jeong-Sam;Han, Soon-Hung;Mun, Du-Hwan
    • Korean Journal of Computational Design and Engineering
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    • v.13 no.2
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    • pp.89-97
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    • 2008
  • Today's manufacturing environment is becoming a distributed manufacturing process in which a unique and specialized technological background is required in specific domains rather than having a single company execute all the manufacturing processes. This phenomenon is especially true in the automotive industry, where the sharing of product data between companies is rampant; however, this kind of interoperability causes many problems. When each company has its own method of managing product data, the sharing of product data in a distributed environment is a major problem. A data translator module or a data mapping module had to be developed for the exchange of data in heterogeneous systems of product data management (PDM); moreover, this type of module must be continually changed and improved due to the fact that PDM systems change for many reasons. In addition, the growth in corporate partnerships deepens the burden of developing and maintaining this module and creates further data exchange problems due to the increasing complexity of the system. This paper introduces a way of exchanging product data among heterogeneous PDM systems through the use of OpenPDM, which is a kind of virtual data warehouse. The implementation of a PDM integrating system is also discussed with respect to the requirement for a logical integration of product data which are physically distributed.

Statistical Patterns in Consonant Cluster Simplification in Seoul Korean: Within-dialect Interspeaker and Intraspeaker Variation

  • Cho, Tae-Hong;Kim, Sa-Hyang
    • Phonetics and Speech Sciences
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    • v.1 no.1
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    • pp.33-40
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    • 2009
  • This study examines how young speakers of Seoul Korean produce tri-consonantal clusters /1kt/ and /1pt/ as in palk-ta ('to be bright') and palp-ta ('to step on'). Production data were collected from 20 speakers of Seoul Korean. The results of narrow transcription of the data showed that simplification is not obligatory as some speakers often preserve all three consonants. When simplified, there was a clear asymmetry between /1kt/ and /1pt/. Speakers showed no clear preference for either C1 preservation (C1=/1/) or C2 preservation (C2=/k/ in /1kt/ and /p/ in /1pt/) in production of /1kt/, but in production of /1pt/, strong preference was found for C1-preserved to C2-preserved variant. When compared with production data in Cho (1999), simplification patterns appear to have changed over the past 10 years, in a direction to preserve the first member of the cluster (/1/) more often, especially with /1kt/. There was no substantial between-item variation, indicating that simplification patterns are not lexically specified. Finally, the results suggest that the process of tri-consonantal simplification has not been fully phonologized in the grammar of the language as evident in substantial inter- and intra-speaker variation.

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The Effect of Crystallization of SLS Glass for Bulletproof Materials (방탄소재 활용을 위한 SLS 유리 결정화의 효과)

  • Shim, Gyu-In;Kim, Tae-Yoon;Choi, Se-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.1
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    • pp.120-125
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    • 2010
  • For application of transparent bulletproof materials, the SLS(soda-lime-silicate) glass was heated by 2-step crystallization. The DTA curve for SLS glass revealed the nucleation and crystal growth temperature at about $575^{\circ}C$ and $675^{\circ}C$, respectively. The crystallized glass was heated at various conditions(temperature, time). As a result, the maximum nucleation and crystal growth rates were $3.8\times10^5/mm^3{\cdot}hr$ at $575^{\circ}C$ and 20.58nm/min at $680^{\circ}C$, respectively. The bending strength, fracture toughness and vickers hardness were 451.7MPa, $0.9388MPa{\cdot}m^{1/2}$, and $693.9H_v$ which were 201%, 31%, and 22% higher than parent glass, respectively. Surface image and transmittance of crystallized SLS glass were analyzed by optical microscopy and UV/VIS/NIR spectrophotometer. Transmittance of crystallized SLS glass at visible-range(200~800nm) was not changed.

Preparation of Diamond Thin film for Electric Device and Crystalline Growth (전자 디바이스용 다이아몬드 박막의 제조 및 결정성장 특성)

  • Kim, Gru-Sik;Park, Soo-Gil;Son, Won-Keun;Fujishiama, Akira
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1720-1723
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    • 2000
  • Boron doped conducting diamond thin film were grown on Si substrate by microwave plasma chemical vapor deposition from a gaseous feed of hydrogen, acetone/methanol and solid boron. The doping level of boron was controlled from 0ppm to $10^4$ppm (B/C). The Si substrate was tilted ca. 10$^{\circ}$ to make Si substrate have different height and temperature. Experimental results show that same condition but different temperature of Si substrate by height made different crystalline of diamond thin film. There were appeared 3$\sim$4 step of different crystalline morphology of diamond. To characterize the boron-doped diamond thin film, Raman spectroscopy was used for identification of crystallinity. To survey surface morphology, microscope was used. Grain size was changed gradually by different temperature due to different height. The Raman spectrum of film exhibited a sharp peak at 1334$cm^{-1}$, which is characteristic of crystalline diamond. The lower position of diamond film position, the more non-diamond component peak appeared near 1550$cm^{-1}$.

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Biosorption of Methylene Blue from Aqueous Solution Using Xanthoceras sorbifolia Seed Coat Pretreated by Steam Explosion

  • Yao, Zeng-Yu;Qi, Jian-Hua
    • Journal of Forest and Environmental Science
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    • v.32 no.3
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    • pp.253-261
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    • 2016
  • Xanthoceras sorbifolia seed coat (XSSC) is a processing residue of the bioenergy crop. This work aimed to evaluate the applicability of using the steam explosion to modify the residue for dye biosorption from aqueous solutions by using methylene blue as a model cationic dye. Equilibrium, kinetic and thermodynamic parameters for the biosorption of methylene blue on the steam-exploded XSSC (SE-XSSC) were evaluated. The kinetic data followed the pseudo-second-order model, and the rate-limiting step was the chemical adsorption. Intraparticle diffusion was one of the rate-controlling factors. The equilibrium data agreed well with the Langmuir isotherm, and the biosorption was favorable. The steam-explosion pretreatment strongly affected the biosorption in some respects. It reduced the adsorption rate constant and the initial sorption rate of the pseudo-second-order model. It enhanced the adsorption capacity of methylene blue at higher temperatures while reduced the capacity at lower ones. It changed the biosorption from an exothermic process driven by both the enthalpy and the entropy to an endothermic one driven by entropy only. It increased the surface area and decreased the pH point of zero charge of the biomass. Compared with the native XSSC, SE-XSSC is preferable to MB biosorption from warmer dye effluents.

Changes in Environmental Attitudes of Middle and High School Students after Anuran Call Monitoring (무미양서류의 음성 신호를 이용한 생물 모니터링의 수행에 따른 중. 고등학생들의 환경 인식 변화)

  • Kim Su-Kyung;Sung Ha-Cheol;Park Dae-Sik;Park Shi-Ryong
    • Hwankyungkyoyuk
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    • v.19 no.1 s.29
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    • pp.104-115
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    • 2006
  • This study was conducted to investigate whether attitudes and recognitions of middle and high school students regarding environmental concerns were improved after anuran call monitoring. It was a step toward monitoring local environmental changes with anuran calls. Three-striped pond frogs (Rana nigromaculata), Bullfrogs (R. catesbeiana), and Narrow-mouthed toads (Kaloula borealis) were surveyed to determine local abundance and distribution of them in 12 study sites using their advertising calls. A published booklet, which contains morphological, physiological, ecological, and acoustic information on amphibian species and methods of monitoring anuran calls were provided to monitoring students for identifying the three species. Pretest-posttest were conducted before and after monitoring from 10 April to 28 August in 2005 to determine how the monitoring students changed their attitudes on environmental issues, increased knowledges on amphibians, and improved the understanding on the cause and effect of declining amphibian populations. The amphibian monitoring program was effective to improve the students' attitudes towards conserving environments as well as the students' knowledge on general behavior and ecology of various amphibian species although their understanding about various environmental problems was not. In addition, the program increased the students' understanding on the problems of declining amphibian populations.

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A Study on the Mechanical Ventilation System of Bathroom in Apartment House (공동주택 화장실의 기계 환기시스템에 관한 연구)

  • 함진식
    • Journal of the Korean housing association
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    • v.12 no.3
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    • pp.141-148
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    • 2001
  • To design mechanical ventilation for bathroom of apartment houses where air supply and exhaust are taken into consideration, mock-ups of ventilation systems, widely used in bathroom of apartment houses with an area of 100$\textrm{m}^2$, were made and installed in a laboratory. These ventilation mock-ups were available for control of air supply and exhaust, and the sizes of supply openings were 40cm${\times}$1cm, 40cm${\times}$3cm, and 40cm${\times}$5cm. They were installed at five positions, spaced 45cm at a height of 5cm from the floor. The exhaust fan was designed for its operating voltage to be set to five steps(100V, 130V, 150V, 180V and 220V) in order to control its air flow rates. When the size and position of each supply opening were changed with the wind velocity of the exhaust fan set to the step 5, the ventilation rates were measured and analyzed by the concentration decay method of tracer gas method, in order to present an efficient mechanical ventilation system. The results of the study revealed that the ventilations rates would increase in the presence of supply openings, compared to the absence of supply openings, and that the larger the size of the supply opening, the more the ventilation rates. Therefore, it was found necessary to take air supply into consideration.

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