• Korean Journal of Plant Taxonomy
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• v.46 no.1
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• pp.65-82
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• 2016

Korean Peninsula Flora Database (KPF database), developed by T.B. Lee Herbarium of Seoul National University comprises ca. 65,000 accessions of vascular plants collected from Korean peninsula from 1850 to 1945. Among these, material from North Korea (Democratic People's Republic of Korea) is represented with ca. 33,000 accessions. The largest part of this material [ca. 4287 accessions (13%) from North Korea] originates from five Japanese and one American collectors, such as Imai, Hanjiro, Mills, Ralph Garfield, Furumi, Masatomi, Nomura, Naohiko, Saito, Tatsumoto, and Okuyama, Shunki from 1909 to 1942. These data are the third largest holding (13%) of North Korean collections after Komarov, V.L and Nakai, T. A part of scientific report about the results of these expeditions had been published before, but the present publication set it sights on giving a first overview of the itineraries and the materials collected by five collectors in North Korea. Among these, Saito has by far the largest collection with 1,730 specimens, followed by five collectors in order with 1,067, 532, 510, 368 and 370 accessions by Mills, Nomura, Okuyama, Furumi, and Imai respectively.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.362-369
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• 2003

A infiltration experiment of river water has been conducted to evaluate the applicability of electrical resistivity monitoring methods in an area containing gravelly deposits in Nagaoka, Japan. Apparent resistivity data, which are inverted to obtain the resistivity distribution, are measured with a newly developed system. This system can collect 490 data in an hour and be controlled with PC to store the data. Subsurface resistivity sections, which are obtained from two-dimensional nonlinear inversion of time-lapse apparent resistivity data, enable us to estimate the direction of the flow and the rate of infiltration. The infiltration rate is estimated to be $4.4{\times}10^4m/s$ in the early stage of the experiment when the infiltration process is dominant.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.54-59
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• 2001

The objective of this research was to develop a screening system for selection of grape downy mildew (Plasmopara viticola)-resistant grape cultivars or seedlings under greenhouse condition. Inoculum concentrations ranging from $10^4$ to $10^5spores/mL$ for screening of resistance were evaluated and $5{\times}10^4spores/mL$ was optimum. Of the tested 14 grape cultivars, Campbell Early and Niagara were resistant to grape downy mildew, Sheridan and Cheongsoo were moderate resistant, while Kaiji, Red Queen and Ruby Okuyama were susceptible under both greenhouse and field conditions. Vitis vinifera grape cultivars were more susceptible to grape downy mildew than V. vinifera-labrusca hybrids and V. vinifera-labrusca-aestivalis hybrids. In V. vinifera-labrusca hybrids, tetraploid grape cultivars were more susceptible than diploid culivars. The evaluated results of grape downy mildew resistance under greenhouse condition were in accordance with those of field condition. Results of this study indicated that both greenhouse and field procedures could be used to screen grape cultivars and seedlings for downy mildew resistance.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.64.1-64
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• 2003

A metal-ferroelectric [SrBi$_2$Ta$_2$O$\_$9/ (SBT)-high-k-insulator(PrOx)-semiconductor(Si) structure has been fabricated and evaluated as a key part of metal-ferroelectric-insulator-semiconductor-field-effect-transistor MFIS-FET memory, aiming to improve the memory retention characteristics by increasing the dielectric constant in the insulator layer and suppressing the depolarization field in the SBT layer. A 20-nm PrOx film grown on Si(100) showed both a high of about 12 and a low leakage current density of less than 1${\times}$ 10e-8 A/$\textrm{cm}^2$ at 105 MV/cm. A 400-nm SBT film prepared on PrOx/Si shows a preferentially oriented (105) crystalline structure, grain size of about 130 nm and subface roughness of 3.2 nm. A capacitance-voltage hysteresis is confirmed on the Pt/SBT/PrOx/Si diode with a memory window of 0.3V at a sweep voltage width of 12 V. The memory retention time was about 1 104s, comparable to the conventional Pt/SBT/SiO$\_$x/N$\_$y/(SiO$\_$N/)/Si. The gradual change of the capacitance indicates that some memory degradation mechanism is different from that in the Pt/SBT/SiON/Si structure.