• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.31-36
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• 2005

Adoxophyes spp. are the major rests of a pear. The larvae attack both leaves and fruits. (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac) and 10-methyldodecyl acetate (10me-12:Ac) have been reported as the sex pheromone components of the genus Adoxophyes. Our objective was to determine the difference in sex pheromone composition of three different A. spp. populations each from Cheonan, Sangju, and Naju area orchards in Korea. Gas chromatography (GC) analyses of pheromone gland extracts of virgin females confirmed the presence of two compounds (Z9-14:Ac and Z11-14:Ac) in Cheonan and Sangju populations, and four compounds (Z9-14:Ac, Z11-14:Ac, E11-14:Ac and tome-12:Ac) in Naju population. The Z9-14:Ac and Z11-14:Ac were detected in the ratio of 80:20 in the Cheonan population and 3:97 in the Sangju population. Females of Naju population produced sex pheromone blend consisting of Z9-14:Ac, Z11-14:Ac, E11-14:Ac and 10me-12:Ac at a ratio of 31:62:6:1. Field trapping tests in pear orchards with Z9-14:Ac and Z11-14:Ac indicated that maximum captures of the male were obtained with traps baited by 80:20 in Cheonan, 10:90 in Sangju, and 30:70 in Naju. These results suggest that there are remarkable geographical variations in the sex pheromone composition of A. spp. in pear orchards in Korea, and taxonomic classification of these species must be carefully assessed.

• Journal of the Korean Mathematical Society
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• v.39 no.2
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• pp.277-287
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• 2002

Let B be the open unit ball with center 0 in the complex space $C^n$. For each q>0, B$_{q}$ consists of holomorphic functions f : B longrightarrow C which satisfy sup z $\in$ B $(1-\parallel z \parallel^2)^q\parallel\nabla f(z)\parallel < \infty$ In this paper, we will show that functions in weighted Bloch spaces $B_{q}$ (0 < q < 1) satifies the following Lipschitz type result for Bergman metric $\beta$: ｜f(z)-f($\omega$)｜< $C\beta$(z, $\omega$) for some constant C.

• Korean Journal of Plant Resources
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• v.10 no.3
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• pp.227-230
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• 1997

The authors isolated four olefinic catechols, commonly referred to as urushiol, from the sap of Korean lacquer tree(Rhus vernicifera STOKES) with stronger antioxidative activities than $\alpha-tocopherol$. The hexane extract with a free radical scavenging activity was purified by silica and ODS gel column chromatography. The active compounds were identified by MS and $^1H-NMR$ as 3-[8'(Z),11'(Z),14'-pentadecatrienyl]catechol, 3-[8'(Z),11'(Z)-pentadecadienyl]catechol, 3-[8'(Z)-pentadecenyl] catechol, and 3-pentadecylcatechol. All of these compounds showed strong free radical scavenging activities on 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical, in which 3-pentadecylacatechol exhibited the highest activity ($IC_{50}$: $1.2{\mu}g/ml$). They also showed a significant inhibitory activity on lipid peroxidation ($IC_{50}$: 2.1 - 3.5 ${\mu}g/ml$). The antioxidative activity of 3-pentadecylcatechol on DPPH radical and lipid peroxidation is approximately two times greater than that of $\alpha$-tocopherol. The results suggest that the urushiol derivatices may contribute to the preservative characteristics effective against oxidative stress and could be a good source for industrial applications including a coating material.

• Archives of Pharmacal Research
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• v.26 no.2
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• pp.132-137
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• 2003

Three cerebrosides 2, 3, and 5 and two terpene glycosides 1 and 4 have been isolated from the methanol extract of the root of Aster scaber. Their structures were determined as 3-Ο-$\beta$-D-glucuronopyranosyl-oleanolic acid methyl ester (1), (2S, 3S, 4R, 2 R, 8Z, 15 Z)-N-2 -hydroxy-15 -tetracosenoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (2), (2S, 3S, 4R, 8Z)-N-octadecanoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (3), 1$\alpha$-hydroxy-6$\beta$-Ο-$\beta$-D-glucosyl-eudesm-3-ene (4), and (2S, 3S, 4R, 2 R, 8Z)-N-2 -hydroxy-hexadecanoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (5) on the basis of spectroscopic methods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.47-60
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• 1975

For the calculation of population parameter and estimation of recruitment of a fish population, an application of multiple regression method was used with some statistical inferences. Then, the differences between the calculated values and the true parameters were discussed. In addition, this method criticized by applying it to the statistical data of a population of bigeye tuna, Thunnus obesus of the Indian Ocean. The method was also applied to the available data of a population of Pacific saury, Cololabis saira, to estimate its recuitments. A stock at t year and t+1 year is, $N_{0,\;t+1}=N_{0,\;t}(1-m_t)-C_t+R_{t+1}$ where $N_0$ is the initial number of fish in a given year; C, number o: fish caught; R, number of recruitment; and M, rate of natural mortality. The foregoing equation is $$\phi_{t+1}=\frac{(1-\varrho^{-z}{t+1})Z_t}{(1-\varrho^{-z}t)Z_{t+1}}-\frac{1-\varrho^{-z}t+1}{Z_{t+1}}\phi_t-a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}C_t+a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}R_{t+1}......(1)$$ where $\phi$ is CPUE; a', CPUE $(\phi)$ to average stock $(\bar{N})$ in number; Z, total mortality coefficient; and M, natural mortality coefficient. In the equation (1) , the term $(1-\varrho^{-z}t+1)/Z_{t+1}$s almost constant to the variation of effort (X) there fore coefficients $\phi$ and $C_t$, can be calculated, when R is a constant, by applying the method of multiple regression, where $\phi_{t+1}$ is a dependent variable; $\phi_t$ and $C_t$ are independent variables. The values of Mand a' are calculated from the coefficients of $\phi_t$ and $C_t$; and total mortality coefficient (Z), where Z is a'X+M. By substituting M, a', $Z_t$, and $Z_{t+1}$ to the equation (1) recruitment $(R_{t+1})$ can be calculated. In this precess $\phi$ can be substituted by index of stock in number (N'). This operational procedures of the method of multiple regression can be applicable to the data which satisfy the above assumptions, even though the data were collected from any chosen year with similar recruitments, though it were not collected from the consecutive years. Under the condition of varying effort the data with such variation can be treated effectively by this method. The calculated values of M and a' include some deviation from the population parameters. Therefore, the estimated recruitment (R) is a relative value instead of all absolute one. This method of multiple regression is also applicable to the stock density and yield in weight instead of in number. For the data of the bigeye tuna of the Indian Ocean, the values of estimated recruitment (R) calculated from the parameter which is obtained by the present multiple regression method is proportional with an identical fluctuation pattern to the values of those derived from the parameters M and a', which were calculated by Suda (1970) for the same data. Estimated recruitments of Pacific saury of the eastern coast of Korea were calculated by the present multiple regression method. Not only spring recruitment $(1965\~1974)$ but also fall recruitment $(1964\~1973)$ was found to fluctuate in accordance with the fluctuations of stock densities (CPUE) of the same spring and fall, respectively.

• The Transactions of the Korean Institute of Power Electronics
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• v.18 no.2
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• pp.123-130
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• 2013

This paper proposes the switched trans Z-source inverter(STZSI) which combined the characteristics of the trans Z-source inverter(TZSI) and the switched inductor Z-source inverter(SLZSI). The proposed STZSI has the same performance compared with the SLZSI which is improved the voltage boost performance of the conventional typical X-shaped ZSI, and it has advantage that circuit structure of Z-impedance network is more simple. And, in order to step up the voltage boost factor under the condition of the same duty ratio, unlike the SLZSI adding the inductors and diodes, the proposed method is dune by changing the turn ratio of trans primary winding of Z-impedance network. To confirm the validity of the proposed method, PSIM simulation and a DSP(TMS320F28335) based experiment were performed using trans with turn ratio 1 and 2 under the condition of the input DC voltage VI=50V, duty ratio D=0.1 and D=0.15. As a result, under the same input/ouput condition, the inverter arm voltage stress of the proposed method is reduced to about 15%-22% as compared with typical X-shaped ZSI, and the elements in Z-impedance network of the proposed method is reduced as compared with the SLZSI.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.172-177
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• 1995

The maneuverabilities of the M.S. TAMYANG are studied, based on maneuvering indices and the data obtained from her Z test. The results obtained are summarized as follows : 1. The maneuvering indices K'and T'of the M.S. TAMYANG are 0.9464, 0.6895 at 10$^{\circ}$Z test and 0.8651, 0.4224 at 20$^{\circ}$Z test and 0.8349, 0.4328 at 30$^{\circ}$Z test respectively. The above calculated values K', T'showed that her maneuverabilities are more effective when the rudder is used to small angle than to large angle. 2. As her maneuvering indices K'and T'at 10$^{\circ}$Z test are smaller than the standard maneuvering indices of fishing boats, her turning ability was found to be lower but her obeying ability higher. 3. The running distance of a turn at her 10$^{\circ}$Z test was about 8.8 times her own length and she was considered to have good maneuverabilities synthetically.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.39.2-39.2
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• 2019

Galaxy clusters are the largest gravitationally bound structures in the universe and located in the densest peak of the dark matter. They can constraint cosmologicals model from their dark matter halo distribution and they are good laboratories to study how galaxy evolution varies with their environment. Especially, studies of galaxy clusters at $z{\geq}1$ are important because (i) galaxy evolution at z >1 is still controversial (Elbaz et al. 2007; Faloon et al. 2013) and (ii) some studies show that mass of galaxy clusters at z>1 seems to be higher than expected value from the concordance LCDM cosmological model (Kang & Im 2009; Gonzales et al. 2012). In spite of their significance, there have not been many studies of galaxy clusters at $z{\geq}1$ because of the lack of wide and deep multi-wavelength data. We newly found galaxy cluster candidates at 0.2 < z < 1.4 and a LSS spanning over 100Mpc at z~0.9 in the ELAIS-N1 field which is one of the IMS (Infrared Medium-deep Survey; Im et al. 2019, in preparation) fields. Thanks to K-GMT science program, we performed spectroscopic follow-up observation for a z~1 galaxy cluster candidates with GMOS of Gemini North and for z~0.9 supercluster candidates with Hectospec of MMT in 2018A and confirmed the large scale structures. We present the newly discovered galaxy overdensities from the observation and the analysis result.

• Journal of Environmental Science International
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• v.31 no.2
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• pp.171-180
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• 2022

Zeolitic material, Z-Y3, was synthesized from coal fly ash (CFA) under low-alkaline conditions (NaOH/CFA ratio = 0.3 and NaOH solution concentrations of 0.0, 0.5, and 1.0 M) using a fusion/hydrothermal method. The adsorption capacities of the fabricated Z-Y3 samples for Cs and Sr ions and the desorption capacity of Na ions were evaluated. The XRD patterns of the Z-Y3 sample fabricated using a 1.0 M NaOH solution (Z-Y3 (1.0 M)) indicated the successful synthesis of a zeolitic material, because the diffraction peaks of Z-Y3 coincided with those of the Na-A zeolite in the 2θ range of 7.18-34.18. Moreover, the SEM images revealed that morphology of the Z-Y3 (1.0 M) sample, which presented zeolitic materials characteristics, consisted of sharp-edged cubes. The adsorption isotherms of Cs and Sr ions on all the fabricated Z-Y3 samples were described using the Langmuir model, and the maximum adsorption capacities of Cs and Sr were calculated to be 0.14-0.94 mmol/g and 0.19-0.78 mmol/g, respectively. The desorption of Na ions from the Cs and Sr ions adsorbed Z-Y3 samples followed the Langmuir desorption model. The maximum desorption capacities of Na ions from the Cs and Sr ions adsorbed Z-Y3 (1.0 M) samples were 1.28 and 1.49 mmol/g, respectively.

• Kyungpook Mathematical Journal
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• v.54 no.4
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• pp.677-684
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• 2014

In the theory of hypergeometric functions of one or several variables, a remarkable amount of mathematicians's concern has been given to develop their transformation formulas and summation identities. Here we aim at generalizing the following transformation formula for the Exton's triple hypergeometric series $X_{12}$ and $X_{17}$: $$(1+2z)^{-b}X_{17}\;\left(a,b,c_3;\;c_1,c_2,2c_3;\;x,{\frac{y}{1+2z}},{\frac{4z}{1+2z}}\right)\\{\hfill{53}}=X_{12}\;\left(a,b;\;c_1,c_2,c_3+{\frac{1}{2}};\;x,y,z^2\right).$$ The results are derived with the help of two general hypergeometric identities for the terminating $_2F_1(2)$ series which were very recently obtained by Kim et al. Four interesting results closely related to the Exton's transformation formula are also chosen, among ten, to be derived as special illustrative cases of our main findings. The results easily obtained in this paper are simple and (potentially) useful.