• Title/Summary/Keyword: North America

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Climatic Characteristics of the Northern Hemisphere Snow Cover observed by Satellite and its influence on the Monsoon

  • Yang, Xiangdong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1289-1291
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    • 2003
  • Climatic characteristic and changes of snow cover over the Northern Hemisphere, Eurasian, North America and the Tibet Plateau are studied based on data of the Northern Hemisphere snow cover area observed by Satellite remote sensing from 1966 to 2003. Meanwhile, the seasons' distribution charts of the Asian snow cover are made, they provide the climatic background of snow cover. In addition, the influences of snow cover on the climate, especially on the monsoon are analysed briefly, and some significance results are concluded.

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The Record of Erysiphe azaleae(Erysiphales) from Poland and Its Anamorph

  • Shin, Hyeon-Dong;Mulenko, Wieslaw
    • Mycobiology
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    • v.32 no.3
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    • pp.105-109
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    • 2004
  • Erysiphe azaleae, a powdery mildew fungus on Rhododendron spp., was originally described from North America, and has only recently been recorded in Germany, England, Switzerland and Poland. The present paper records plentiful collections of this species from Poland, and provides additional information of its anamorphic state for taxonomic purposes.

Hydrurus foetidus (Chrysophyceae): an update and request for observations

  • Klaveness, Dag
    • ALGAE
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    • v.34 no.1
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    • pp.1-5
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    • 2019
  • Hydrurus foetidus is a cold-water golden alga (Chrysophyceae) found in fast-flowing rivers mainly during time of snowmelt. It has primarily been studied by scientists located near alpine or northern locations, but there are also observations both in south and north America, Russia, Japan, in the Hope Bay area (Antarctica) and Himalaya. If and where environmental conditions are appropriate, Hydrurus may be distributed "worldwide." More information is wanted from areas where its presence may be expected.

Phylogenetics of Trichaptum Based on Mitochondrial Small Subunit rDNA Sequences

  • Ko, Kwan-Soo;Jung, Hack-Sung
    • Journal of Microbiology
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    • v.35 no.4
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    • pp.259-263
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    • 1997
  • To study the phylogenetic relationships of species of Trichaptum and to infer intraspecific dibergence of T. abietinum, partial mitochondrial small subunit rDNA sequences were determined. Six strains of T. abietinum, two of T. biforme, and one of T. fusco-violaceum were examined. Parsimony and distance analyses showed that each Trichaptum species forms a distinct group and that T. abietinum consists of two or more subgroups. Strains from North America were distantly related to one another but the European strain formed an independent group with three Korean strains, suggesting the possibility that Korean taxa may be phylogenetically closer to European taxa than to North American taxa.

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Genetic Diversity of Wild and Cultivated Populations of American Ginseng (Panax Quinquefolium) from Eastern North America Analyzed by RAPD Markers

  • Lim, Wan-Sang
    • Korean Journal of Medicinal Crop Science
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    • v.13 no.5
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    • pp.262-269
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    • 2005
  • The objective of this study was to assess genetic diversity among 6 different wild ginseng populations from New York, Kentucky, North Carolina, Pennsylvania, Tennessee and Virginia, and to compare these wild populations to one cultivated population. RAPD markers were used to estimate the genetic difference among samples from the 7 populations. The 64 random primers were screened, and 15 primers were selected which exhibited the 124 highly reproducible polymorphic markers. The ratio of discordant bands to total bands scored was used to estimate the genetic distance within and among populations. Multidimensional scaling (MDS) of the relation matrix showed distinctive separation between wild and cultivated populations. The MDS result was confirmed using pooled chi-square tests for fragment homogeneity. This study suggests that RAPD markers can be used as population-specific markers for American ginseng.

Experimental human infection with Fibricola cratera (Trematoda: Neodiplostomidae)

  • Shoop, Wesley-L.
    • Parasites, Hosts and Diseases
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    • v.27 no.4
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    • pp.249-252
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    • 1989
  • Fibricola cratera is a strigeoid trematode indigenous to North America that, heretofore, was known only to infect wild mammals. Herein, it is reported that an experimental inoculation of a human volunteer produced a patellt infection that lasted 40 months. Symptoms of epigastric discomfort, loose stools and flatulence occurred over the first year of infection and ameliorated thereafter. Eggs per gram of stool were low (${\leq}2$) throughout the course of infection and were not detected by the standard technique of formalin-ether concentration. To monitor infection, the entire stool sample was examined each month after sieving through No. 10 (pore size 2 mm) and 100 (pore size $145{\;}{\mu\textrm{m}}$) sieves and collecting eggs on a No. 325 (pore size $45{\;}{\mu\textrm{m}}$) sieve. This is the first report of a North American strigeoid trematode capable of maturing in a human and is only the second species of strigeoid known to do so. The other species is F. seoulensis which has been implicated in 26 human infections in Korea.

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UPWELLING FILAMENTS AND THEIR ROLE IN CROSSFRONTAL WATER EXCHANGE

  • Kostianoy, A.G.;Soloviev, D.M.
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.954-957
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    • 2006
  • Satellite data (thermal and color imagery) show that offshore flowing filaments off the west coasts of North America, North and South Africa can influence significantly the cross-frontal mixing in the coastal upwelling zones. To evaluate this role, we investigated structure, dynamics and behavior of surface filaments in the Canary and Benguela upwelling regions on the base of daily satellite IR and VIS imagery (AVHRR NOAA, MODIS-Aqua). It was found that seasonal variability of the filaments location depends on intra-annual shift of general upwelling intensity along the coast. The main statistical characteristics of filaments - length, width, temperature anomaly and estimates of velocity were obtained. Estimates of cross-frontal water exchange due to filamentation based on the statistical data show that these coherent structures play a major role in the water and particle exchange between coastal zone and the open ocean in both upwelling regions.

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A Study on Development of Online Wide Area SynchroPhasor and Voltage Stability Monitoring System using Satellite Network (위성망을 이용한 온라인 광역 동기위상 및 전압안정도 감시 시스템 개발에 관한 연구)

  • Kwon, Dae-Yun;Kim, Tae-Jin;Yoon, Sang-Hyun;Jung, Gwang-Gyun;Oh, Gyu-Whan
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.273-274
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    • 2008
  • Recently, the most wide-area blackout in North America, Canada and Europe had shown us indirectly the importance of Wide-Area Power System Protection and had influence on the direction of domestic electric power industry. After reorganization of the electric power industry in 2001, market incentives controls the power generation, transmission and distribution rather than stability of power grid, and moreover it produce bad results like inefficient facility management and too much competition. In addition, we can easily predict the massive loss of social and economic when the wide-area outage occurs by north direction load flow which is a pending problems of domestic power system and in a changed industry likes hi-tech manufacture and information technology industries. This paper introduces the development of infra systems for prevent wide-area blackout in situations of the power system operations.

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동북아시아에 있어서의 해저 광케이블 구성 전략

  • 윤장용;조준구
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.5
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    • pp.395-402
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    • 1991
  • Submarine Optical Fiber Cable Link becomes a major transmission madi a in many countries and Continents thanks to development of low attenuation fiber and its capability of carryung broadband data. United States of America and Japan are aggressively planning to construct international submarine optical fiber links in North-East Asia. But the links do not connect Korea and Korea becomes isolated in the international communication network. This paper shows a strategy on submarine optical fibre cable links that make Korea a HUB station in North East As a without heavy investment.

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