• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.6
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• pp.723-730
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• 2013

The speed-limit regulation on a turnout is the main factor inhibiting the speed-up of conventional lines. The specified speed for a train moving through a turnout system is lower than that for a train traveling over the general track. This is done to ensure the running safety of a railway vehicle moving through a turnout. In this study, the shape change example of the guard rail component of a turnout in the Daegu Metropolitan Transit Corporation (DTRO) system was studied. A theoretical examination of the geometrical interaction formula according to wheel/rail shape at the turnout was conducted. Running safety analysis by changing the length of the guard rail on the F10/F12 turnout using the developed analysis techniques (by VI-Rail) was achieved, and the effect on railway safety was examined accordingly.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.6
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• pp.591-598
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• 2011

When a vehicle passes through a turnout, it is necessary for the changes in lateral force to be minimized to ensure the safe running of the vehicle. Therefore, the analysis of the interaction between the vehicle and the turnout is crucial for estimating the lateral force and the derailment coefficient on the turnout. In this paper, the effect of the variation of section shape on the running safety of a vehicle was investigated by changing the shape of the point part and the crossing part. The tongue rail length of the point part and nose rail height of the crossing part of an F10/F12 turnout were changed, and the running safety of the vehicle was analyzed.

• Culinary science and hospitality research
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• v.17 no.1
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• pp.93-109
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• 2011

This study explores the effect of parent-brand attitude on the purchase intention of an extended brand for expanding a foodservice brand and the interaction effect between parent-brand attitude and perceived risk by fit for the purchase intention of an expanded brand using the proof analysis. As a result, the main effects among parent-brand attitude(F(1,295)=12.012, p<0.01), fit(F(1,295)=17,758, p<0.001), perceived risk(F(1,295)=12.570, p<0.01) and the purchase intention of an expanded brand were significant statistically. Also, for the purchase intention of an expanded brand, not only the effect of interactions between parent-brand attitude and perceived risk(F(1,295)=5.782, p<0.05) but the effect of interactions among parent-brand attitude, fit and perceived risk(F(1,295)=6.068, p<0.05) were significant. In addition, there was difference between parent-brand attitude to purchase intention and the interaction effect of perceived risk by the fit of an extended brand.

• Communications of the Korean Mathematical Society
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• v.12 no.3
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• pp.709-715
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• 1997

For a fibration (E,B,p) with fiber F and a fiber map f, we show that if the inclusion $i : F \to E$ has a left homotopy inverse, then $G^f_n(E,F)$ is isomorphic to $G^f_n(F,E) \oplus \pi_n(B)$. In particular, by taking f as the identity map on E we have $G_n(E,F)$ is isomorphic to $G_n(F) \oplus \pi_n(B)$.

• Elastomers and Composites
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• v.47 no.1
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• pp.23-29
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• 2012

The silica-silica interaction parameter (${\alpha}_F$) of the silane treated silica filled natural rubber (NR) compound was investigated. As silane (TESPT) concentration increased from 2 to 12% (2, 4, 6, 8, 10, 12%), the ${\alpha}_F$ value increased at the same silica concentration (10, 20, 30, and 40 phr). It seemed the sulfur atoms in TESPT acted as a crosslinking agent in the compound. As silica concentration increased from 10 to 40 phr, the ${\alpha}_F$ value increased at the same silane concentration due to increased silica-silica interaction.

• Journal of the Chungcheong Mathematical Society
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• v.12 no.1
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• pp.63-72
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• 1999

We introduce a concept of fuzzy linearity: A function $F:L^0(X){\rightarrow}\mathbb{R}$ is fuzzy linear if $F[({\alpha}{\wedge}f){\vee}(b{\wedge}g)]=[a{\wedge}F(f)]{\vee}[b{\wedge}F(g)]$ for $f,g{\in}L^0(X)$ and a, b > 0. We show that a fuzzy integral is fuzzy linear if the measure is fuzzy c-additive.

• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.351-358
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• 2003

We prove the generalized Hyers-Ulam stability of a quadratic functional equation f($\chi$+ y + z) + f($\chi$) + f(y) + f(z) = f($\chi$+ y) + f(y + z) + f(z + $\chi$) for the functions defined between Banach modules over a Banach algebra.

• The Mathematical Education
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• v.12 no.2
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• pp.5-12
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• 1974

단위원을 가지는 하환환에 있어서의 Prime Spectrum에 관하여 다음 세가지 사실을 증명하였다. 1. X를 환 R의 prime spectrum, C(X)를 X에서 정의되는 실연적함수의 환, X를 C(X)의 maximal spectrum이라 하면 X는 C(X)의 prime spectrum의 부분공간으로서의 한 T-space로 된다. N을 환 R의 nilradical이라 하면, R/N이 regula 이면 X와 X는 위상동형이다. 2. f: R$\longrightarrow$R'을 ring homomorphism, P를 R의 한 Prime ideal, $R_{p}$, R'$_{p}$를 각각 S=R-P 및 f(S)에 관한 분수환(ring of fraction)이라 하고, k(P)를 local ring $R_{p}$의 residue' field라 할 때, R'의 prime spectrum의 부분공간인 $f^{*-1}$(P)는 k(P)(equation omitted)$_{R}$R'의 prime spectrum과 위상동형이다. 단 f*는 f*(Q)=$f^{-1}$(Q)로서 정의되는 함수 s*:Spec(R')$\longrightarrow$Spec(R)이다. 3. X를 환 S의 prime spectrum, N을 R의 nilradical이라 할 때, 다음 네가지 사실은 동치이다. (1) R/N 은 regular 이다. (2) X는 Zarski topology에 관하여 Hausdorff 공간이다. (3) X에서의 Zarski topology와 constructible topology와는 일치한다. (4) R의 임의의 원소 f에 대하여 f를 포함하지 않는 R의 prime ideal 전체의 집합 $X_{f}$는 Zarski topology에 관하여 개집합인 동시에 폐집합이다.폐집합이다....

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3738-3742
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• 2013

The reaction mechanism of $SiF_2$ radical with HNCO has been investigated by the B3LYP method of density functional theory(DFT), while the geometries and harmonic vibration frequencies of reactants, intermediates, transition states and products have been calculated at the B3LYP/$6-311++G^{**}$ level. To obtain more precise energy result, stationary point energies were calculated at the CCSD(T)/$6-311++G^{**}$//B3LYP/$6-311++G^{**}$ level. $SiF_2+HNCO{\rightarrow}IM3{\rightarrow}TS5{\rightarrow}IM4{\rightarrow}TS6{\rightarrow}OSiF_2CNH(P3)$ was the main channel with low potential energy, $OSiF_2CNH$ was the main product. The analyses for the combining interaction between $SiF_2$ radical and HNCO with the atom-in-molecules theory (AIM) have been performed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.147-155
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• 2016

Purpose: In this study, the relationship between the interpersonal relationships, clinical stress and satisfaction of clinical practice among nursing was examined. Method: The participants were 261. Data collected from 7 September to 18 September 2015 were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression. Result: The mean scores for the interpersonal relationship ($3.74{\pm}0.39$), stress ($3.21{\pm}0.54$), and satisfaction ($3.44{\pm}0.45$) in clinical practice were above average. Interpersonal relationships differed significantly according to year (F=3.12, p=.046), satisfaction with nursing as a major (F=15.84, p<.001), important of interpersonal relationships (F=4.76, p=.001), and academic achievement (F=3.80, p=.011). Stress in clinical practice differed significantly according to the year (F=8.05, p<.001), application motivation (F=4.55, p=.001) and satisfaction with nursing as a major (F=2.69, p=.046). Satisfaction in clinical practice differed significantly according to satisfaction with nursing as a major (F=3.24, p=.022), important of interpersonal relationships (F=3.01, p=.019), and academic achievements (F=5.24, p=.002). Significant correlations were observed between the interpersonal relationships and satisfaction in clinical practice (r=.24, p<.001). Interpersonal relationship (${\beta}=.21$, p<.001), academic achievements (${\beta}=.12$, p=.045) were factors influencing satisfaction in clinical practice. Conclusion: The interpersonal relationships need to be improved to increase nursing students' satisfaction with clinical practice