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A taxonomic review of Adonis pseudoamurensis W. T. Wang (Ranunculaceae) (개복수초(미나리아재비과)의 분류학적 재고)

  • Son, Dong Chan;Ko, Sung Chul
    • Korean Journal of Plant Taxonomy
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    • v.42 no.4
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    • pp.316-323
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    • 2012

  • Morphological characters of Adonis pseudoamurensis W. T. Wang and its related species were examined to illustrate its taxonomic entity, and their new key was made. As a result, it shows that A. ramosa Franch., an endemic species in Japan, was sparsely pubescent on the abaxial surface of the leaf and petiole, and its sepal was as long as its petal. However, A. pseudoamurensis is glabrous on the same surfaces and its sepal was shorter than its petal. In addition, A. multiflora Nishikawa et Ko. Ito was clearly distinguished in that it had acuminate leaf apices, linear shape of the final lobes of leaf and scales on the branched stem. Meanwhile, A. pseudoamurensis featured petiolate at cauline leaves and pubescent on pistils, and these characters were common with their allied groups. But diagnostic key characters suggested by the original description such as sessile at cauline leaves and glabrous on pistils were not observed in this study.

  • https://doi.org/10.11110/kjpt.2012.42.4.316 인용 PDF KSCI

Characterization of High Temperature Oxide Scales formed on Ni-18%W Coatings (Ni-18%W 코팅의 고온산화막 분석)

  • Ko J. H;Lee D. B
    • Korean Journal of Materials Research
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    • v.14 no.4
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    • pp.281-286
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    • 2004

  • The oxide scales formed on Ni-18W(at.%) coating that was electrodeposited on steel were investigated using XRD, SEM and TEM. The oxide scales consisted mainly of an outer NiO layer, and an inner thick ($NiWO_4$+NiO) mixed layer. The unoxidized coating below the oxide scale was rich in Ni and depleted in W, owing to the consumption of Wand the resultant Ni enrichment. The oxidation resistance of Ni-18W coating was poorer than that of the TiN coating, due to the formation of nonprotective NiWO$_4$. During oxidation, Ni and the substrate element of Fe diffused outward, while oxygen inward, according to the concentration gradients.

  • https://doi.org/10.3740/MRSK.2004.14.4.281 인용 PDF KSCI

Design and fabrication of current limiting InP Gunn diode for W-band waveguide FTO (W-band 도파관 FTO 적용을 위한 전류제한 InP Gunn diode 설계 및 제작)

  • Ko, Dong-Sik;Kwak, No-Seong;Kim, Young-Jin;Heo, Jun-Woo;Ko, Pil-Seok;Kim, Sam-Dong;Park, Hyun-Chang;Rhee, Jin-Koo;Chun, Young-Hoon;Lee, Seok-Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.3
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    • pp.45-54
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    • 2014

  • In this paper, We have designed and fabricated 20 InP Gunn diodes using a current limiting epitaxial structure by MINT's optimized fabrication processes. We have also packaged the fabricated InP Gunn diodes using our optimized packaging method, and then designed and fabricated a W-band waveguide FTO to measure characteristics of the packaged InP Gunn diodes. The packaged InP Gunn diode have a ceramic ring, a Au plated stud and a lid, and a Maltese cross. The fabricated InP Gunn diodes have good RF characteristics such as high output powers (11.8~17 dBm) and limiting low currents (less than 400 mA) between 92.9 and 94.78 GHz.

  • https://doi.org/10.5573/ieie.2014.51.3.045 인용 PDF KSCI