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Ahn, Young-Ho
- Honam Mathematical Journal
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- v.31 no.4
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- pp.591-599
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- 2009
For given ${\alpha},{\omega}\;{\in}\;{\mathbb{R}}$ and ${\beta}$ > 1, let $T_{{\beta},{\alpha},{\omega}}$ be the skew-product transformation on the torus, [0, 1) ${\times}$ [0, 1) defined by (x, y) ${\longmapsto}\;({\beta}x,y+{\alpha}x+{\omega})$ (mod 1). In this paper, we give a criterion of ergodicity and weakly mixing for the transformation $T_{{\beta},{\alpha},{\omega}}$ when the natural extension of the given ${\beta}$-transformation can be viewed as a generalized baker's transformation, i.e., they flatten and stretch and then cut and stack a two-dimensional domain. This is a generalization of theorems in [10].
https://doi.org/10.5831/HMJ.2009.31.4.591 인용 PDF

Kizildere, Elif;Soydan, Gokhan
- Honam Mathematical Journal
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- v.42 no.1
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- pp.139-150
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- 2020
Let p be a prime number with p > 3, p ≡ 3 (mod 4) and let n be a positive integer. In this paper, we prove that the Diophantine equation (5pn² - 1)^x + (p(p - 5)n² + 1)^y = (pn)^z has only the positive integer solution (x, y, z) = (1, 1, 2) where pn ≡ ±1 (mod 5). As an another result, we show that the Diophantine equation (35n² - 1)^x + (14n² + 1)^y = (7n)^z has only the positive integer solution (x, y, z) = (1, 1, 2) where n ≡ ±3 (mod 5) or 5 | n. On the proofs, we use the properties of Jacobi symbol and Baker's method.
https://doi.org/10.5831/HMJ.2020.42.1.139 인용 PDF KSCI

Ko, Byoung-Seob
- Applied Biological Chemistry
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- v.37 no.5
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- pp.397-401
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- 1994
Bioreduction with active dried baker's yeast proceeded smoothly in n-hexane, pentane or petroleum ether as an organic solvent system. Ethyl(1) and octyl 3-oxohexanoate(2) were reduced to $({\underline{R}})-ethyl(3)$ and $({\underline{S}})-octyl$ 3-hyroxy-hexanoate(4) with high enantiomeric excess, respectively.
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권도헌;김훈수
- Animal Systematics, Evolution and Diversity
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- v.2 no.1
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- pp.43-48
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- 1986
Collections of isopod custaceans from the south coasts of Korea contained a new species of sphaeromatid genus Dynoides . Description is given under the name of Dynoides spinipodus. The proposed new species is allied to D. serratisinus BArnard, 1914, D. barnardi Baker, 1928 and D.Dentisinus Shen , 1929 in the presence of a conical median process on the pleon , but it is readily distinguished by the pleotelsonic foramen without maginal teeth along its inner border.
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