• 한국안광학회지
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• 제18권3호
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• pp.247-251
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• 2013

목적: 본 연구에서는 누진렌즈 안경 처음 착용자의 가입도를 비교 분석하였다. 방법: 2001년부터 2013년까지 광주광역시 소재의 안경원을 방문한 41~78세의 노안인 사람 중에 안질환이 없고 누진렌즈 안경을 처음 처방받은 636명을 대상으로 굴절상태와, 성별, 연령대에 따른 가입도를 각각 분석하였다. 결과: 성별에 따른 가입도 차이는 남성이 1.71 D, 여성이 1.67 D로 나타났고, 굴절이상에 따른 가입도는 정시안이 1.67 D, 근시안이 1.74 D, 원시안이 1.90D로 나타났으며 연령대에 따른 가입도는 41~44세는 1.26 D, 45~49세는 1.48 D, 50~54세는 1.72 D, 55~59세는 1.84D, 60~64세는 2.10 D, 65세 이상은 2.43 D로 나타났다. 근시안의 분류에 저도근시는 1.58 D, 중등도근시는 1.48 D, 고도근시는 1.67 D로 나타났고 난시안의 분류에는 직난시는 1.80 D, 도난시는 1.64 D, 사난시는 1.65 D이었다. 결론: 누진렌즈의 가입도는 굴절이상과 난시의 종류, 연령에 따라 차이가 있었다.

• Korean Journal of Mathematics
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• 제19권1호
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• pp.17-24
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• 2011

Let X, Y be vector spaces. It is shown that if an even mapping $f:X{\rightarrow}Y$ satisfies f(0) = 0, and $$2(_{2d-2}C_{d-1}-_{2d-2}C_d)f\({\sum_{j=1}^{2d}}x_j\)+{\sum_{{\iota}(j)=0,1,{{\small\sum}_{j=1}^{2d}}{\iota}(j)=d}}\;f\({\sum_{j=1}^{2d}}(-1)^{{\iota}(j)}x_j\)=2(_{2d-1}C_d+_{2d-2}C_{d-1}-_{2d-2}C_d){\sum_{j=1}^{2d}}f(x_j)$$ for all $x_1$, ${\cdots}$, $x_{2d}{\in}X$, then the even mapping $f:X{\rightarrow}Y$ is quadratic. Furthermore, we prove the Hyers-Ulam stability of the above functional equation in Banach spaces.

• 한국환경과학회지
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• 제18권12호
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• pp.1325-1330
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• 2009

The fumigant 1,3-dichloropropene (1,3-D) was recently proposed as a direct replacement for methyl bromide ($CH_3Br$) in soil fumigation. This study was conducted to better understand behavior phase partitioning, diffusion and volatilization of 1,3-D as affected by isomer. The Henry's law constant(KH) of cis-1,3-D and trans-1,3-D was 0.058 and 0.037 at $20^{\circ}C$, respectively. $K_H$ of cis form of 1,3-D was higher than that of trans form of 1,3-D. To compare with volatilization of 1,3-D isomer, soil column [70 cm (length)${\times}$12 cm (i.d.)] included a shank injection at 30 cm with 300 kg $ha^{-1}$. Maximum cis-1,3-D and trans-1,3-D concentration reached 57 mg $L^{-1}$ and 39 mg $L^{-1}$ at 30 cm depth at 1h after application. Cumulatively, after 10 days, 51.8% and 43.57% of applied cis-1,3-D and trans-1,3-D was emitted via volatilization, respectively. The total losses of cis-1,3-D were significantly greater than that of trans-1,3-D. Finally, cis-1,3-D and trans-1,3-D, such as isomer are dominant of 1,3-D fates in soil.

• 한국농공학회논문집
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• 제60권5호
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• pp.135-147
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• 2018

The objective of this study was to analyze the characteristics of combined 1D/2D inundation simulation of riverside farmland using the Hydrologic Engineering Center - River Analysis System (HEC-RAS). We compared and analyzed inundation simulation results between 1D and combined 1D/2D hydraulic simulation using HEC-RAS. Calibration and validation of stream stage were performed using three rainfall events. The coefficient of determination ($R^2$) and root mean square error (RMSE) between simulated and observed stream stage were 0.935 - 0.957 and 0.250 m - 0.283 m in calibration and validation, respectively. The inundation area showed no significant difference in 1D and combined 1D/2D simulation ($8.48km^2$ in 1D simulation, $8.75km^2$ in combined 1D/2D simulation). The average inundation depth by 1D simulation was 1.4 m deeper than combined 1D/2D simulation. In the lower inundation depth, the inundation area by combined 1D/2D simulation was larger than inundation area by 1D simulation. As the inundation depth increased, the inundation area by 1D simulation became wider. In the case of the 1D/2D combined simulation, low elevation areas along the river bank were inundated widely. Compared to 1D/2D combined simulation, the flood radius in some sections was longer in 1D simulation. In the 1D analysis, because the low altitude riverside farmlands are also assumed to stream, it is calculated that riverside farmlands have the same stage as the mainstream when the stream is overflowed. Therefore, the inundation area seems to be overestimated in those sections. In other regions, the inundation areas tend to be broken depending on overflow by each stream cross-section. In the case of river flooding, the overflow is expected to flow to the lower area depending on the terrain, such as the results of the combined 1D/2D simulation. It is concluded that the results of combined 1D/2D inundation simulation reflected the topographical characteristics of low-lying farmland.

• 생약학회지
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• 제30권2호
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• pp.168-172
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• 1999

Five compounds were isolated from the roots of Polygala tenuifolia (Polygalaceae). On the basis of spectroscopic evidences, the structures of these compounds were characterized as ${\alpha}-D-(6-O-sinapoyl)-glucopyranosyl(1{\rightarrow}2')-{\beta}-D-(3'-O-sinapoyl)-fructofuranoside$ (P3), ${\alpha}$-D-{6-O-(p-methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4), ${\alpha}$-D-{6-O-(p-hydroxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P5), ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6), $1,5-anhydro-D-glucitol$(P7) respectively. ${\alpha}$-D-{6-O-(p-Methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4) and ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6) were isolated for the first time from the genus of Polygala. 1,5-Anhydro-D-glucitol(P7) was isolated without hydrolysis for the first time from the root of Polygala tenuifolia.

• 한국수산과학회지
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• 제12권1호
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• pp.1-6
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• 1979

본연구에서는 그물어구의 상사를 지배하는 무차원수 K를 $$K=\frac{{\nu}^n\rho_wv^{2-n}}{{d^{1+n}(\rho-\rho_w)}$$ d, p: 재료의 직경 및 밀도 $\nu,\rho_w,v$: 물의 동점성계수, 밀도 및 속도으로 정하고, 여기에서의 직경의 비를 결정하는 방법에 따라 실물과 모형과의 상사를 완전하게 그리고 근사적으로 만족시키는 조건들을 구하였다. 즉, 원전한 상사한 경우는 직경의 비를 축척비와 같게 하고, 나아가서 다른 모든 치수의 비도 축척비와 같게 함으로써 만족된다고 하였으며, 측사적 상사의 경우느 직경의 비가 축척비 $(\frac{\lambda_2}{\lambda_1})$와 같지 않아도 된다고 하여, 그물실의 직경 d, 코의 크기 $\iota$ 및 콧수 N의 비를 $$\frac{d_2}{d_1}=\frac{\iota_2}{\iota_1}=\frac{\lambda_2}{\lambda_1}{\cdot}\frac{N_1}{N_2}$$ 으로, 줄의 직경 d', 길이 $\iota'$ 및 밀도 $\rho'$의 비를 $$\frac{d_2'}{d_1'}=\sqrt{{\frac{\lambda_2}{\lambda_1}}\cdot{\frac{d_2}{d_1}}\cdot{\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}}\cdot{\frac{\rho_1'-\rho_{w1}}{\rho_2'-\rho_{w2}}}}$$, $\frac{\iota_2'}{\iota_1'}=\frac{\lambda_2}{\lambda_1}$로, 부속구의 치경 $d'$, 밀도 $\rho'$ 및 수 $N'$의 비를 $$\frac{N_2'}{N_1'}=(\frac{\lambda_2}{\lambda_1})^2(\frac{d_2}{d_1})(\frac{d_1'}{d_2'})\frac{(\rho_2-\rho_{w2})}{(\rho_1-\rho_{w1})}\frac{(\rho_1'-\rho_{w1})}{(\rho_2'-\rho_{w2})}$$으로 정하였다. 이렇게 정해진 모형어구에 대해 유속 v의 비느 $K_1=K_2$로부터 $$(\frac{u_2}{u_1})^{2-n}=(\frac{\nu_2}{\nu_1})^{-n}\;(\frac{\rho_{w1}}{\rho_{w2}})\;(\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}})\;(\frac{d_2}{d_1})^{1+n}$$으로 주어지므로, 이를 이용하여 어구저항 D 및 그물감의 다리에서의 장력 $\tau$의 비를 $$\frac{D_2}{D_1}=\frac{d_2(\rho_2-\rho_{w2})}{d_1(\rho_1-\rho_{w1})}(\frac{\lambda_2}{\lambda_1})^2$$ $${\frac{\tau_2}{\tau_1}=\frac{d_2\iota_2(\rho_2-\rho_{w2})}{d_1\iota_1(\rho_1-\rho_{w1})}\;{\cdot}\frac{\lambda_2}{\lambda_1}$$로 정하였다.

• 대한수학회보
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• 제37권4호
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• pp.803-810
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• 2000

Let N($d_1,...,{\;}d_n;c_1,...,{\;}c_n$) be the number of solutions $(x_1,...,{\;}x_n){\in}F^{n}_p$ of the diagonal equation $c_lx_1^{d_1}+c_2x_2^{d_2}+{\cdots}+c_nx_n^{d_n}{\;}={\;}0{\;}n{\geq},{\;}c_j{\;}{\in}{\;}F^{*}_q,{\;}j=1,2,...,{\;}n$ where $d_j{\;}>{\;}1{\;}and{\;}d_j{\;}$\mid${\;}q{\;}-{\;}1$ for all j = 1,2,..., n. In this paper, we find all n-tuples ($d_1,...,{\;}d_n$) such that the reduced form of ($d_1,...,{\;}d_n$) and N($d_1,...,{\;}d_n;c_1,...,{\;}c_n$) are the same as in the theorem obtained by Sun Qi [3]. Improving this, we also get an explicit formula for the number of solutions of the diagonal equation, unver a certain natural restriction on the exponents.

• 한국작물학회지
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• 제54권3호
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• pp.249-259
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• 2009

Puroindoline alleles, grain characteristics, milling performances and physical properties of flour of 22 Korean wheat cultivars were evaluated to determine the influence of puroindolines genotypes on grain and flour characteristics and to provide useful information for improving milling and end-use quality in Korean wheat breeding programs. Nine Korean wheat cultivars carried with Pina-D1a/Pinb-D1a, 11 cultivars had Pina-D1a/Pinb-D1b and 2 cultivars were Pina-D1b/Pinb-D1a. Korean wheats carrying with Pina-D1a/Pinb-D1a genotypes showed lower test weight and thousand kernel weight, area and roundness of grain and hardness index in grain characteristics, lower flour yield and higher proportion of break flour in milling performances and lower average particle size of flour, ash and damaged starch content, water retention capacity, yellowness-blueness and higher lightness of flour than wheats with Pina-D1a/Pinb-D1b or Pina-D1b/Pina-D1a genotypes. Pina-D1a/Pinb-D1b genotypes showed lower 1000-kernel weight, grain area, higher average of particle size of flour, higher ash and damaged starch content than Pina-D1b/Pina-D1a genotypes. There was no difference in hardness index of grain, milling performances, flour color between Pina-D1a/Pinb-D1b and Pina-D1b/Pina-D1a genotypes. These results could present the information to improve milling quality and physical properties of flour in Korean wheat breeding programs.

• Journal of applied mathematics & informatics
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• 제17권1_2_3호
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• pp.605-614
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• 2005

We show that an Artinian O-sequence $h_0,h_1,{\cdots},h_{d-1},h_d\;=\;h_{d-1},h_{d+l}\;>\;h_d$ of codimension 3 is not level when $h_{d-1}\;=\;h_d\;=\;d + i\;and\;h{d+1}\;=\;d+(i+1)\;for\;i\;=\;1,\;2,\;and\;3$, which is a partial answer to the question in [9]. We also introduce an algorithm for finding noncancelable Betti numbers of minimal free resolutions of all possible Artinian O-sequences based on the theorem of Froberg and Laksov in [2].

• 대한수학회보
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• 제49권4호
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• pp.767-774
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• 2012

For a positive square-free integer $d$, let $t_d$ and $u_d$ be positive integers such that ${\epsilon}_d=\frac{t_d+u_d{\sqrt{d}}}{\sigma}$ is the fundamental unit of the real quadratic field $\mathbb{Q}(\sqrt{d})$, where ${\sigma}=2$ if $d{\equiv}1$ (mod 4) and ${\sigma}=1$ otherwise For a given positive integer $l$ and a palindromic sequence of positive integers $a_1$, ${\ldots}$, $a_{l-1}$, we define the set $S(l;a_1,{\ldots},a_{l-1})$ := {$d{\in}\mathbb{Z}|d$ > 0, $\sqrt{d}=[a_0,\overline{a_1,{\ldots},2a_0}]$}. We prove that $u_d$ < $d$ for all square-free integer $d{\in}S(l;a_1,{\ldots},a_{l-1})$ with one possible exception and apply it to Ankeny-Artin-Chowla conjecture and Mordell conjecture.