• Title/Summary/Keyword: regional materials

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Development and Application of Regional Learning System for 3rd Grade (초등학교 3학년을 위한 지역화 학습 시스템 개발 및 적용 - 경기도 평택 지역을 중심으로 -)

  • Hwang, Sun-Young;Goh, Byung-Oh
    • Journal of The Korean Association of Information Education
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    • v.12 no.1
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    • pp.49-56
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    • 2008
  • It can be said that the feature of elementary education on Society studies is localization of all curriculum. Among them, the social curriculum of 3rd grade emphasizes on character of local and living experiences. Also the Society studies of 7th curriculum reform focused on new types of localization materials and way of practical using because of development on internet and computer communication, To correspond this need, this paper suggests regional learning system based on the web. which is designed for social studies of 3rd grade student to study Pyeongtaek-City, in Gyeonggi-do. Also, current school field education materials which is elementary 3rd grade localization supporting text can be used as well as it can be provided through the web educational system to support the needed localization materials for the students.

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Biochemical Characterization of an Extracellular ${\beta}$-Glucosidase from the Fungus, Penicillium italicum, Isolated from Rotten Citrus Peel

  • Park, Ah-Reum;Hong, Joo-Hee;Kim, Jae-Jin;Yoon, Jeong-Jun
    • Mycobiology
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    • v.40 no.3
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    • pp.173-180
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    • 2012
  • A ${\beta}$-glucosidase from Penicillium italicum was purified with a specific activity of 61.8 U/mg, using a chromatography system. The native form of the enzyme was an 88.5-kDa tetramer with a molecular mass of 354 kDa. Optimum activity was observed at pH 4.5 and $60^{\circ}C$, and the half-lives were 1,737, 330, 34, and 1 hr at 50, 55, 60, and $65^{\circ}C$, respectively. Its activity was inhibited by 47% by 5 mM $Ni^{2+}$. The enzyme exhibited hydrolytic activity for p-nitrophenyl-${\beta}$-D-glucopyranoside (pNP-Glu), p-nitrophenyl-${\beta}$-D-cellobioside, p-nitrophenyl-${\beta}$-D-xyloside, and cellobiose, however, no activity was observed for p-nitrophenyl-${\beta}$-D-lactopyranoside, p-nitrophenyl-${\beta}$-D-galactopyranoside, carboxymetyl cellulose, xylan, and cellulose, indicating that the enzyme was a ${\beta}$-glucosidase. The $k_{cat}/K_m\;(s^{-1}mM^{-1})$ values for pNP-Glu and cellobiose were 15,770.4 mM and 6,361.4 mM, respectively. These values were the highest reported for ${\beta}$-glucosidases. Non-competitive inhibition of the enzyme by both glucose ($K_i=8.9mM$) and glucono-${\delta}$-lactone ($K_i=11.3mM$) was observed when pNP-Glu was used as the substrate. This is the first report of non-competitive inhibition of ${\beta}$-glucosidase by glucose and glucono-${\delta}$-lactone.

Evaluation on Mechanical Properties with Welding Processes for Off Shore Wind Tower Application (TMCP강을 적용한 해상용 풍력타워의 용접 공정에 따른 기계적 물성 평가)

  • Ji, Changwook;Choi, Chul Young;Nam, Dae-Geun;Kim, Hyoung Chan;Jang, Jae Ho;Kim, Ki Hyuk;Park, Yeong-Do
    • Journal of Welding and Joining
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    • v.32 no.1
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    • pp.15-21
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    • 2014
  • FCAW(Flux Cored Arc Welding), SAW(Submerged Arc Welding), EGW(Electro Gas Welding), and three-pole SAW are applicable in manufacturing the offshore wind tower. In this paper, mechanical properties of these welded-joints for TMCP steels were evaluated in all above welding processes. The tensile strength of welded-joints for all the welding methods satisfied the standard guideline (KS D 3515). No cracking on weldment was found after the bending test. Changes of weldedments hardness with welding processes were observed. In a weld HAZ (heat-affected zone), a softened HAZ-zone was formed with high heat input welding processes (SAW and EGW). However, the welded-joint fractures were found in the base metal for all cases and small decrease in welded-joint strength was caused by a softened zone. The multi-pole SAW welds exhibited similar mechanical properties comparing to the one with one-pole SAW process.

Locational Characteristics of Recycling Industries (재생용 사업의 입지적 특성)

  • Han, Ju-Seong
    • Journal of the Korean association of regional geographers
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    • v.10 no.4
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    • pp.775-786
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    • 2004
  • Establishments of wholesale of recycling materials are located in the region where an amount of recyclable wastes generated as artery industry developed and the region of rather many population. And they are located not in underpopulated area as noxious facilities, but located in the non-residential area of many population regions in the whole country. Also, establishments of recycling of metal wastes and scrap, and non-metal wastes and scrap are mainly located in the peripheral region of metropolitan cities, regional centered cities, and adjacent regions of industrial area, because of high coefficient of localization, and agglomerated effects of production. The factor influencing the location of recycling industries is deeply connected with the location of wholesale of recycling materials, and thus, the transportation costs to carry recycling materials from supplied regions to plants are important but population is not so important.

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Characterization of Conducting Polymer/CdTe Nanoparticles/Carbon Nanotube Composites in Thin Films (전도성 고분자/CdTe 나노입자/탄소 나노튜브 복합박막의 특성 연구)

  • Kim, Do-Hoon;Shim, Seong Eun;Kim, Jungsoo;Nam, Dae-Geun;Oh, Weontea
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.4
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    • pp.315-320
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    • 2013
  • The composites composed of conducting polymer (MEH-PPV), CdTe nanoparticles, and multiwalled carbon nanotubes (MWNTs) were spectroscopically and electrically characterized in their thin films. The composite films were prepared by spray coating. These composites were prepared from the mixture solution of MEH-PPV and CdTe-embedded MWNTs, in which CdTe nanoparticles were electrostatically bound to MWNTs. UV/vis and PL spectra were analyzed to investigate the optical absorbance and emission of the composite films. In addition, their structural, electrochemical, and electrical properties were studied by transmission electron microscopy, cyclic voltammetry, and I-V measurement.

Interfacial Properties of Electrodeposited Carbon Fibers Reinforced Epoxy Composites Using Fragmentation Technique and Acoustic Emission

  • Yeong-Min Kim;Joung-Man Park;Ki-Won Kim;Dong-Jin Yoon
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 1999.11a
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    • pp.28-31
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    • 1999
  • Carbon fiber/epoxy composites using electrodeposited monomeric and polymeric coupling agents were compared with the dipping and the untreated cases. Treating conditions such as time, concentration and temperature were optimized. Four-fibers embedded micro-composites were prepared for fragmentation test. Interfacial properties of four-fiber composites with different surface treatments were investigated with simultaneous acoustic emission (AE) monitoring. The microfailure mechanisms occurring from fiber break, matrix and interlayer crackings were examined by AE parameters and an optical microscope. It was found that interfacial shear strength (IFSS) of electrodeposited carbon fibers was much higher than the other cases under dry and wet conditions. Well separated and different-shaped AE groups occurs for the untreated and ED treated case, respectively.

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Research Trend of Additive Manufacturing Technology - A=B+C+D+E, add Innovative Concept to Current Additive Manufacturing Technology: Four Conceptual Factors for Building Additive Manufacturing Technology -

  • Choi, Hanshin;Byun, Jong Min;Lee, Wonsik;Bang, Su-Ryong;Kim, Young Do
    • Journal of Powder Materials
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    • v.23 no.2
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    • pp.149-169
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    • 2016
  • Additive manufacturing (AM) is defined as the manufacture of three-dimensional tangible products by additively consolidating two-dimensional patterns layer by layer. In this review, we introduce four fundamental conceptual pillars that support AM technology: the bottom-up manufacturing factor, computer-aided manufacturing factor, distributed manufacturing factor, and eliminated manufacturing factor. All the conceptual factors work together; however, business strategy and technology optimization will vary according to the main factor that we emphasize. In parallel to the manufacturing paradigm shift toward mass personalization, manufacturing industrial ecology evolves to achieve competitiveness in economics of scope. AM technology is indeed a potent candidate manufacturing technology for satisfying volatile and customized markets. From the viewpoint of the innovation technology adoption cycle, various pros and cons of AM technology themselves prove that it is an innovative technology, in particular a disruptive innovation in manufacturing technology, as powder technology was when ingot metallurgy was dominant. Chasms related to the AM technology adoption cycle and efforts to cross the chasms are considered.

Corrosion Properties of Dissimilar Friction Stir Welded 6061 Aluminum and HT590 Steel

  • Seo, Bosung;Song, Kuk Hyun;Park, Kwangsuk
    • Metals and materials international
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    • v.24 no.6
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    • pp.1232-1240
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    • 2018
  • Corrosion properties of dissimilar friction stir welded 6061 aluminum and HT590 steel were investigated to understand effects of galvanic corrosion. As cathode when coupled, HT590 was cathodically protected. However, the passivation of AA6061 made the aluminum alloy cathode temporarily, which leaded to corrosion of HT590. From the EIS analysis showing Warburg diffusion plot in Nyquist plots, it can be inferred that the stable passivation layer was formed on AA6061. However, the weld as well as HT590 did not show Warburg diffusion plot in Nyquist plots, suggesting that there was no barrier for corrosion or even if it exists, the barrier had no function for preventing and/or retarding charge transport through the passivation layer. The open circuit potential measurements showed that the potential of the weld was similar to that of HT590, which lied in the pitting region for AA6061, making the aluminum alloy part of the weld keep corrosion state. That resulted in the cracked oxide film on AA6061 of the weld, which could not play a role of corrosion barrier.

A study on the library interlending system in Germany (통일 독일의 상호대차제도에 관한 연구)

  • Ro Moon-Ja
    • Journal of the Korean Society for Library and Information Science
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    • v.23
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    • pp.303-350
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    • 1992
  • In the modem information society any library can not meet the need of its user without cooperation with other libraries. After the Second World War the old West Germany in the general kept the traditional library system, but (the library system of) the old Estern Germany was influenced by the Soviet Union. The East and West Germany have developed their library interlending system on their own way, but their system was based on the regional principle. After the Unification the library interlending system of two parts of Germany is on the way to an uniform system. Above all East Germany libraries must now collect the materials which they could not buy during about 40 years due to the ideological aspect and lacking financial resources. The Deutsche Forschungsgemeinschaft tries here to help the East German libraries. Before reaching the final settlment of two different library interrlending rules the East and West German libraries temporary serve their user on the previous way, it means in the regional princeple. During this periode the East and West German libraries agree to cooperate on the base of partnership between their regional central catalog. If the East German user's wish can not be satisfied in the East German library, then this wish is sent to its Western partner regional central catalog.

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Analysis of Road Snow-removal Infrastructure using Road Snow-removal Historical Data (도로제설 이력자료 기반 제설 인프라 분석)

  • Kim, Jin Guk;Kim, Seoung Bum;Yang, Choong Heon
    • International Journal of Highway Engineering
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    • v.19 no.3
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    • pp.83-90
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    • 2017
  • PURPOSES : In this study, systematic road snow-removal capabilities were estimated based on previous historical data for road-snowremoval works. The final results can be used to aid decision-making strategies for cost-effective snow-removal works by regional offices. METHODS : First, road snow-removal historical data from the road snow-removal management system (RSMS), operated by the Ministry of Land, Infrastructure and Transport, were employed to determine specific characteristics of the snow-removal capabilities by region. The actual owned amount and actual used amount of infrastructure were analyzed for the past three years. Second, the regional offices were classified using K-means clustering into groups "close" to one another. Actual used snow-removal infrastructure was determined from the number of snow-removal working days. Finally, the correlation between the de-icing materials used and infrastructure was analyzed. Significant differences were found among the amounts of used infrastructure depending on snowfall intensity for each regional office during the past three years. RESULTS:The results showed that the amount of snow-removal infrastructure used for low heavy-snowfall intensity did not appear to depend on the amount of heavy snowfall, and therefore, high variation is observed in each area. CONCLUSIONS:This implies that the final analysis results will be useful when making decisions on snow-removal works.