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Floristic study of Mt. Baekasan (백아산의 식물상)

  • Sun, Eun-Mi;Kim, Byeol-Ah;Son, Hyun-Deok;Jeong, Jeong-Chae;Im, Hyoung-Tak
    • Korean Journal of Plant Taxonomy
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    • v.47 no.3
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    • pp.236-263
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    • 2017
  • This study presents a discussion of vascular plants found on Mt. Baekasan, Hwasun-gun, Jeollanam-do, based on specimens collected during 32 separate field trips amounting to a total of 36 days conducted between May of 2011 and October of 2016. There are 651 taxa on Mt. Baekasan, consisting of 109 families, 366 genera, 576 species, 5 subspecies, and 70 varieties. Twelve plants endemic to Korea were found, including Cirsium setidens (Dunn) Nakai and Scutellaria insignis Nakai. There are a total of 61 taxa of floristic regional indicator plants specially designated by the Ministry of the Environment. Rare plants such as Jeffersonia dubia (Maxim.) Benth. & Hook. ex Baker & S. Moore in Mt. Baekasan are 17 taxa in total, and red list plants number 8 taxa, including Cremastra variabilis (Blume) Nakai ex Shibata. Nine calciferous plants were found, including Asplenium ruprechtii Sa. Kurata, Ulmus davidiana var. japonica (Rehder) Nakai and Morus cathayana Hemsl. Thirty-three naturalized plants were also found, including Ambrosia artemisiifolia and Rumex acetosella.

Adaptation Strategy in Dry Matter and Seed Production of Rice and Weed Species (벼와 잡초(雜草)의 건물생산(乾物生産) 및 종자생산(鐘子生産) 특성(特性)에 따른 환경적응(環境適應) 전략(戰略))

  • Kim, Soon-Chul;Moody, Keith
    • Korean Journal of Weed Science
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    • v.9 no.3
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    • pp.183-200
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    • 1989
  • An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

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Comparison of early tertiary mathematics in USA and Korea (미국과 한국의 초기 고등수학 발전과정 비교연구)

  • Lee, Sang-Gu;Seol, Han-Guk;Ham, Yoon-Mee
    • Communications of Mathematical Education
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    • v.23 no.4
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    • pp.977-998
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    • 2009
  • In this article, we give a comparative study on the last 300 years of USA and Korean tertiary mathematics. The first mathematics classes in United States were offered before July, 1638, but the real founding of tertiary mathematics courses was in 1640 when Henry Dunster assumed the duties of the presidency at Harvard. President Dunster read arithmetics and geometry on Mondays and Tuesdays to the third year students during the first three quarters, and astronomy in the last quarter. So tertiary mathematics education in United States began at Harvard which is the oldest college in USA. After 230 years since then, Benjamin Peirce in 1870 made a major and first American contribution to mathematics and got an attention from European mathematicians. Major change on the role of Harvard mathematics from teaching to research made by G.D. Birkhoff when he joined as an assistant professor in 1912. Tertiary mathematics education in Korea started long before Chosun Dynasty. But it was given to only small number of government actuarial officers. Modern mathematics education of tertiary level in Korea was given at Sungkyunkwan, Ewha, Paichai, and Soongsil. But all college level education opportunity, particularly in mathematics, was taken over by colonial government after 1920. And some technical and normal schools offered some tertiary mathematics courses. There was no college mathematics department in Korea until 1945. After the World War II, the first college mathematics department was established, and Rimhak Ree in 1949 made a major and first Korean contribution to modern mathematics, and later found Ree group. He got an attention from western mathematicians for the first time as a Korean. It can be compared with Benjamin Peirce's contribution for USA.

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