• Title/Summary/Keyword: LES data

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한국 금-은광화작용과 천열수 광상의 성인모델: 탐사에의 적용

  • 최선규;박상준;김창성
    • Proceedings of the KSEEG Conference
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    • 2002.10a
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    • pp.119-136
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    • 2002
  • Contrasts in the style of the gold-silver mineralization in geologic and tectonic settings in Korea, together with radiometric age data, reflect the genetically different nature of hydrothermal activities, coinciding with the emplacement age and depth of Mesozoic magmatic activities. It represents a clear distinction between the plutonic settings of the Jurassic Daebo orogeny and the subvolcanic environments of the Cretaceous Bulgugsa igneous activities. Dunng the Daebo igneous activities (c.a. 200~150 (\ulcorner) Ma) coincident with orogenic time, gold mineralization took place between c.a. 195 and 135 (127 \ulcorner) Ma. The Jurassic Au deposits commonly show several characteristics; prominent association with pegmatites, low Ag/Au ratios In the ore-concentrating parts, massive vein morphology and a distinctively simple mineralogy including Fe-rich sphalerite, galena, chalcopyrite, arsenopyrite, Au-rich electrum, pyrrhotite and/or pyrite. During the Bulgugsa igneous activities (110~50 Ma), the precious-metal deposits are generally characterized by such features as complex vein morphology, medium to high Ag/Au ratios in the ore concentrates, and diversity of ore minerals including base-metal sulfides, pyrite, arsenopyrite, Ag-rich eletrum and native silver with Ag sulfides, Ag-Sb-As sulfosalts and he tellurides. Vein morphology, mineralogical, fluid inclusion and stable isotope results indicate the diverse genetic natures of hydrothermal systems in Korea. The Jurassic Au-dominant deposits (orogenic type) were formed at the relatively high temperature (about 300$^{\circ}$ to 45$0^{\circ}C$) and deep-crustal level (4.0$\pm$1.5 kb) from the hydrothermal fluids containing more amounts of magmatic waters ($\delta$$^{18}$ $O_{H2O}$; 5~10$\textperthousand$). It can be explained by the dominant ore-depositing mechanisms as $CO_2$ boiling and sulfidation, suggestive of hypo- to mesothermal environments. In contrast, the Cretaceous Au-dominant (l13~68 Ma), Au-Ag (108~47 Ma) and AE-dominant (103~45 Ma) deposits, which correspond to volcanic-plutonic-related type, occurred at relatively low temperature (about 200$^{\circ}$ to 35$0^{\circ}C$) and shallow-crustal level (1.0$\pm$0.5 kb) from the ore-forming fluids containing more amounts of less-evolved meteonc waters ($\delta$$^{18}$ $O_{H2O}$;-10~5$\textperthousand$). These characteristics of the Cretaceous precious-metal deposits can be attributed to the complekities in the ore-precipitating mechanisms (mixing, boiling, cooling), suggestive of epi- to mesothermal environments. Therefore, the differences of the emplacement depth between the Daebo and the Bulgugsa igneous activities directly influence the unique temporal and spatial association of the deposit styles.les.

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Phylogenetic Relationships and Characterization of Korean Native Silkworm Strains Based on RAPDs and Isozyme Analysis, Bombyx mori (동위효소 및 RAPD분석에 의한 한국재래종 누에계통의 계통학적 특성)

  • 이재만;노시갑
    • Journal of Sericultural and Entomological Science
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    • v.43 no.2
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    • pp.59-66
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    • 2001
  • This study was conducted to elucidate phylogenetic relationships and genetic characterization of silkworms that might be recognized as the Korean native strains. Genetic characterization in isozymes and the proteins of larval hemolymph of 17 silkworms were observed by acrylamide gel eletrophoresis, on 12 genes; Bph, Bes, les, Amy-hc, Ict-A, -B, -D,-E,-H, Pfl, Pst, Lp. Gene frequencies in each locus were compared other geographic strains. Korean native strains were remarkably different from others considered as the genetic characterization of Korean native strains. Phylogenetic relationships in Korean native strains were analysed using RAPD-PCR markers. A total of 40 primers were used and 346 bands of amplified DNA were generated from geographic strains. Genetic similarity based on the RAPD bands was used to construct phylogenetic dendrogram based on analysis of bard sharing data of amplified markers. Genetic similarity ranged from 0.595 to 0.860. In the genetic relationship based on dendrogram, they were classified into Bombyx mori group (including 16 domesticated silkworm strains) and B. mandarina group. The Bombyx mori group was separated into three sub-groups at the genetic similarity of 0.6930, including Korean, Japanese and Chinese groups. According to this result, the Korean native variety can be considered as a clearly different variety from other geographic strains. It may be concluded that the Korean native strains are also one of original geographic variety such as Japanese, Chinese, etc.

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Bourdieu and Photography -A Critical Review of Bourdieu's Works in the Sociology of Photography- (부르디외와 사진 : 사진행위에 대한 부르디외의 분석이 갖는 의의와 한계)

  • Joo, Hyoung-Il
    • Korean journal of communication and information
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    • v.17
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    • pp.145-178
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    • 2001
  • Bourdieu is one of the few social science researchers who were interested in photography. Bourdieu's work on photography appears principally in two books: Un art moyen: Essai sur les usagrs sociaux de la photographie(1965) and La distinction(1979). In these books, Bourdieu analyzes the role of photography in the family life of peasants and small town and urban dwellers. He shows how different classes and groups express their esthetic worldview in response to different photographs and photographic styles. What Bourdieu analyzed is not just photography but ways of photographing and ways of looking at pictures. Through these analyses, Bourdieu explores the social definition of photography. Bourdieu's ideas on photographic practice in social life are as follows. First, the photography, especially family photography generally practiced, has the integrative function. It recreates the group by ritualizing and solemnizing the important moments of social life in which the group reaffirms its unity. Second, the photography as esthetic practice in search of legitimacy as a fine art becomes a means by which different classes are pitted against each other. Each of classes gives its own meaning to photographic practice. Despite its originality and persuasive power, Bourdieu's work on photography has its own limits. The data used by Bourdieu are 35 years old and relevant to European social life. Things has changed since. First, the technological improvement and innovation in photography was considerable. Cheap and good photographic materials, easy to operate, made photographic practice everybody's everyday activity. New media like camcorder and digital camera made photography one of the industrial discards like jukebox. It means that photography does not function as important means of distinction between classes any longer. The integrative function of the photography becomes more ambiguous too. Second, the esthetic status of the photography has changed. The family photography was already integraed into fine art. Photography is not a middle-brow art any more. Bourdieu's work on photography shows how photography was used by different social classes in European social life of the 1960's. His work is historically and geographically limited. Moreover, his work was ordered by the french affiliate of Eastman Kodak Company. And all along the analysis, Bourdieu didn't hide his intention of distinguishing his sociological method from the other methods, especially psychological one. These mean that Bourdieu's work was done in a specific context, for specific purposes. In this respect, Bourdieu's work on photography, like every sociological work, can not claim to be universal.

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