• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.5
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• pp.1058-1063
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• 1997

Though the Preparata code of length 8 over $Z_{4}$ satisfies the chain condition, the Preparata code of length 16 or 32 over $Z_{4}$ does not satisfy the chain condition. In this paper we show that the Preparata code of length $2^{m}$ over $Z_{4}$ does not satisfy the chain condition for m=4, 5, 6 and 8 by investigating relations between weight hierarchy and chain condition.

• Bulletin of the Korean Mathematical Society
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• v.58 no.2
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• pp.419-431
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• 2021

In this paper we discuss the classical problem of finding conditions on the entire coefficients A(z) and B(z) guaranteeing that all nontrivial solutions of f" + A(z)f' + B(z)f = 0 are of infinite order. We assume A(z) is an entire function of completely regular growth and B(z) satisfies three different conditions, then we obtain three results respectively. The three conditions are (1) B(z) has a dynamical property with a multiply connected Fatou component, (2) B(z) satisfies T(r, B) ~ log M(r, B) outside a set of finite logarithmic measure, (3) B(z) is extremal for Denjoy's conjecture.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.1-10
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• 2005

In the lepidopteran surveys in Mt. Changbai, China, during 2000-2003, 10 species of the genus Zanclognatha Lederer of Noctuidae were recognized. Of them, a new species, Zanclognatha lui sp. novo is described, two species (Zanclognatha umbrosalis Staudinger and Z. perfractalis Bryk) are reported for the first time from China, and four species (Z. fumosa, Z. lilacina, Z. violacealis and Z. tarsipennalis) are newly known from Mt. Changbai. Synonymies, distributional ranges, photos of the genitalia, and images of the new and newly recorded species are given.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.95-100
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• 2016

Seeded variety of zoysiagrass has not been bred yet in Korea. Development of seeded zoysiagrass cultivar will be very important for the growth of turfgrass industry internationally as well as domestically. This research was conducted to investigate seed yield and germinability of 102 collected native zoysiagrass ecotypes in South Korea. Two hundred and seventy seven ecotypes were collected from various locations including coastal and mountain areas, while 102 morphologically distinct and seed producing ecotypes were selected and planted in $1m{\times}1m$ maintenance plots. Seed yield ranged from 0.1 to $32.2g\;m^{-2}$. Highest yielding line was a medium leaf type zoysiagrass of Z6011 with $32.2g\;m^{-2}$. Most collected lines showed seed germination rates of below 50%. However, Z2095 showed highest germination rate of 78%. Considering germination rate and seed yield, collected lines of Z6011, Z 6015, Z1075, ZN1008, and Z1084, which were mostly medium leaf type and Z. japonica types, showed reasonably high potential to be used as breeding lines for high yield seed varieties of zoysiagrass.

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.915-931
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• 2009

The non-rigid molecule group theory in which the dynamical symmetry operations are defined as physical operations is applied to deduce the character table of the full non-rigid molecule group (f-NRG) of 2,3,5,6-Tetramethylpyrazine The f-NRG of this molecule is seen to be isomorphic to the group $\mathbb{Z}_3{\wr}(\mathbb{Z}_2{\times}\mathbb{Z}_2)$, where $\mathbb{Z}_n$ is the cyclic group of order n, of order 324 which has 45 conjugacy classes. We determine the some properties and relations between characters of the group. Also, we examine the symmetry group of this molecule and show that its symmetry group is $\mathbb{Z}_2{\times}\mathbb{Z}_2$.

• Bulletin of the Korean Mathematical Society
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• v.61 no.3
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• pp.745-762
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• 2024

In this paper, we study the existence of finite order meromorphic solutions of the following non-linear difference equation fⁿ(z) + P_d(z, f) = p₁e^α1z + p₂e^α2z + p₃e^α3z, where n ≥ 2 is an integer, P_d(z, f) is a difference polynomial in f of degree d ≤ n - 2 with small functions of f as its coefficients, p_j (j = 1, 2, 3) are small meromorphic functions of f and α_j (j = 1, 2, 3) are three distinct non-zero constants. We give the expressions of finite order meromorphic solutions of the above equation under some restrictions on α_j (j = 1, 2, 3). Some examples are given to illustrate the accuracy of the conditions.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.339-348
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• 2012

To survey the seagrass distribution in Jeju and Chuja Islands, we directly observed seagrass beds using SCUBA in July, 2011. Distributional area, species composition, morphology, density, and biomass of seagrasses and environmental characteristics were examined in investigation sites. In particular, three protected seagrass species (Zostera marina, Z. caulescens and Z. caespitosa) were found in the investigation areas. While the three species were found in Chuja Island, only Z. marina was distributed in Jeju Island. Z. marina was distributed only north-eastern coast of Jeju Island, and the total coverage was $238,572m^2$. Total seagrass coverage of Chuja Island was $23,584m^2$. In detail, Z. caulescens Z. caespitosa and Z. marina were 21,216, 1,870 and $498m^2$, respectively. Of these, Z. marina was found from the intertidal to subtidal zones of 5m MSL (mean sea level) depth. Z. caespitosa and Z. caulescens were found in subtidal zones of 3~4 m and 4~6m MSL depth, respectively.

• Journal of the Korean Ceramic Society
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• v.13 no.4
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• pp.5-8
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• 1976

Both oriented and non-oriented ferroxplana $Co_{1-x}Zn_xZ(Ba_3Co_{2(1-x)}Zn_{2x} Fe_{24}O_{41})$ with x=0.00, 0.45 were prepared by conventional ceramic method. The magnetostrictions of thus prepared specimens were measured by use of the three terminal capacitor device at room temperature. The magnitude of measured values was approximately five times greater than that of ZnY ferroxplana. The easy-magnetization plane at room temperature of both CoZ and Co0.55 $Zn_{0.45}$Z was their basal plane. The magentostrictions in the basal plane and the other planes showed saturated values at magnetic field intensity of about 2Koe and 4Koe, respectively. The magnetostriction constants $K_1, \; K_2, \;K_3\; and\; K_4$ for CoZ were -2.4, -10.5, -5.9 and -45.2$\times10^{-6}$ , while those for $Co_{0.55}Zn_{0.45}Z$ were +0.1, -1.2, -6.3 and -39.0$\times$10^{-6}, , respectively.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.2
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• pp.197-208
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• 2008

In this paper, we obtain the Hyers-Ulam-Rassias stability of a Cauchy-Jensen functional equation $$f(x+y,z)-f(x,z)-f(y,z)=0,\\2f(x,\frac{y+z}2)-f(x,y)-f(x,z)=0$$ in the spirit of Th. M. Rassias.

• The Pure and Applied Mathematics
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• v.16 no.2
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• pp.167-178
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• 2009

In this paper, we obtain the generalized Hyers-Ulam stability of a Cauchy-Jensen functional equation f(x+y, z)-f(x, z)-f(y, z)=0, $$2f\;x,\;{\frac{y+z}{2}}-f(x,\;y)-f(x,\;z)=0$$ in the spirit of P. $G{\breve{a}}vruta$.