• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.668-678
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• 2017

Intermolecular interactions were studied for binary mixtures of 2-propanol + cyclohexane, n-hexane, benzene, toluene, o-, m- and p-xylenes by measuring ultrasonic speeds (u) over the entire range of composition at 298.15 K and 308.15 K. From these results the deviation in ultrasonic speed was calculated. These results were fitted to the Redlich-Kister equation to derive the binary coefficients along with standard deviations between the experimental and calculated data. Acoustic parameters such as excess isentropic compressibility ($K_s^E$), intermolecular free length ($L_f$) and available volume ($V_a$) were also derived from ultrasonic speed data and Jacobson's free length theory. The ultrasonic speed data were correlated by Nomoto's relation, Van Dael's mixing relation, impedance dependence relation, and Schaaff's collision factor theory. Van Dael's relation gives the best prediction of u in the binary mixtures containing aliphatic hydrocarbons. The ultrasonic speed data and isentropic compressibility were further analyzed in terms of Jacobson's free length theory.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.296-303
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• 2001

Kachanov-Rabotnov(K-R) creep damage theory was reviewed, and applied to design a creep curve for type 316LN stainless steel. Seven coefficients used in the theory, i.e., A, B, k, m, λ, r, and q were determined, and their physical meanings were analyzed clearly. In order to quantify a damage parameter ($\omega$), cavity amount was measured in the crept specimen taken from interrupted creep test with time variation, and then the amount was reflected into K-R damage equations. Coefficient λ, which is regarded as a creep tolerance feature of a material, increased with creep strain. Mater curve with λ=2.8 was well coincided with an experimental one to the full lifetime. The relationship between damage parameter and life fraction was matched with the theory at exponent ${\gamma}$=24 value. It is concluded that K-R damage equation was reliable as the modelling equation for type 316LN stainless steel. Coefficient data obtained from type 316LN stainless steel can be utilized for life prediction of operating material.

• Journal of The Korea Institute of Healthcare Architecture
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• v.13 no.3
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• pp.7-14
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• 2007

The concept and spatial composition of office have endlessly changed according to social trend. And according to social change, members of office, namely, concept of organization has been changed. Presently, our society finds and needs appearance of office suitable for our society. According to a concept of ecological environment and a concept laying stress on human, various trials have been performed but still, stress of salaried men is treated as social issue. By having connection between psychological healing theory of Max $L{\ddot{\bar{u}}}scher$ and spatial expression elements (content : refuge, self-esteem : prospect, confidence : flow, liberty : void) as a theory, we discussed possibility of aesthetic office landscape could be developed to a type of office which could control emotion that can be a cause of stress and we intended to examine limitation and possibility through case analysis.

• Child Health Nursing Research
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• v.25 no.2
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• pp.223-233
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• 2019

Purpose: The purpose of this study was to investigate the effect of the moderate drinking program based on social cognitive theory on changes in the drinking habits of college students with drinking problems. Methods: This study included a total of 68 college students with drinking problems. These participants participated in 10 sessions of a moderate drinking program in which social cognitive theory was applied. Changes in the cognition and behaviors of the participants were then investigated. Results: The moderate drinking program based on social cognitive theory for college students with drinking problems was effective in increasing the subjects' drinking-related knowledge (U=191.50, p<.001), enhancing their drinking refusal self-efficacy(t=8.02, p<.001), and changing their drinking-related attitudes (U=108.50, p<.001), drinking outcome expectancy (t=8.68, p<.001), amount of drinking in a single session ($x^2=25.72$, p<.001), number of drinking sessions per month ($x^2=10.05$, p=.006), and problem drinking behaviors (t=5.77, p<.001). Conclusion: These results can be used to inform a regular on-campus intervention programs for moderate drinking, and to implement education about moderate drinking, thereby increasing the success rate of drinking reduction.

• Bulletin of the Korean Mathematical Society
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• v.50 no.5
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• pp.1693-1710
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• 2013

In this paper, we consider the biharmonic elliptic systems of the form $$\{{\Delta}^2u=F_u(u,v)+{\lambda}{\mid}u{\mid}^{q-2}u,\;x{\in}{\Omega},\\{\Delta}^2v=F_v(u,v)+{\delta}{\mid}v{\mid}^{q-2}v,\;x{\in}{\Omega},\\u=\frac{{\partial}u}{{\partial}n}=0,\; v=\frac{{\partial}v}{{\partial}n}=0,\;x{\in}{\partial}{\Omega},$$, where ${\Omega}{\subset}\mathbb{R}^N$ is a bounded domain with smooth boundary ${\partial}{\Omega}$, ${\Delta}^2$ is the biharmonic operator, $N{\geq}5$, $2{\leq}q$ < $2^*$, $2^*=\frac{2N}{N-4}$ denotes the critical Sobolev exponent, $F{\in}C^1(\mathbb{R}^2,\mathbb{R}^+)$ is homogeneous function of degree $2^*$. By using the variational methods and the Ljusternik-Schnirelmann theory, we obtain multiplicity result of nontrivial solutions under certain hypotheses on ${\lambda}$ and ${\delta}$.

• Journal of the Korean Geotechnical Society
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• v.35 no.3
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• pp.17-24
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• 2019

The purpose of this study is to understand the characteristics of bearing capacity of shallow foundation on the grounds. We made a comparative study of existing bearing capacity theory, based on the three-dimensional finite element analysis with a variety of conditions such as ground condition, foundation scale and foundation shape. In the finite element analysis, the ultimate bearing capacity showed a gradual convergence in the form of exponential function or logarithm function according to the foundation scale. Although the shear strength increased, the bearing capacity tended not to increase but change linearly. In the results of comparative study of existing bearing capacity theory, bearing capacity ratio ($q_{u(FEA)}/q_{u(theory)}$) of pure sand has the outcome closest to those of the Terzaghi method. Pure clay turned out to be about 0.4~0.6 while normal soil was changed in a range of 0.3~1.3. As shear strength is increased, the results turned out to be less than 1.0. Bearing capacity ratio ($q_u/q_{u(1.0)}$), normalized at 1.0m bearing capacity, was about 35%, 15% and 5% of theoretical formula under the condition of ${\phi}=25^{\circ}$, $30^{\circ}$ and $35^{\circ}$ of pure sand; no scale effect was found with pure clay and the normal soil with lower soil strength level showed less than 10% of the theoretical formula of pure sand. Bearing capacity ratio of each case, in accordance with, the shear strength increase, was largely influenced by the internal friction angle. Shape factor of bearing capacity ratios classified by foundation shapes have different results according to the shapes; the shape factor of circular foundation is 1.50, square foundation is 1.30, rectangular and continuous foundations are 1.1~1.0.

• Journal of Fashion Business
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• v.21 no.3
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• pp.80-92
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• 2017

Fashion trend is more than a social phenomenon that multitudes of people accept as popular styles of clothing. The purpose of this study was to understand the influence of fashion trend over time and distance. Geographically thousands of miles apart, the U.S. has strongly influenced fashion in Korea, revealed by references and historic depictions collected from literature and web sites. Results of the study are summarized as five issues: First, emergence of female missionaries from the U.S. American missionaries working in the late Great Korean Empire performed a significant role importing Western culture to Korea. Second, as opportunities of education increased, women studying abroad introduced Western fashion to Koreans when they returned to Korea. They were more open to Western culture than other Koreans and moderately harmonized their Korean sentiment and Western culture, mitigating cultural shock and enabled other Koreans to accept Western culture. Third, the effect of fashionistas on media. Singers working for U.S. armies stationed in Korea and movie stars appearing in Hollywood movies profoundly affected Korean pop culture and fashion trends in Korea. Fourth, following First Lady Jacqueline Kennedy of the U.S. She was an influential figure in those days and a fashion leader as well. Lastly, acceptance of working girl fashion depicted in American television shows. American working girls depicted on American TV shows were highly admired by young Korean women, so the fashion of American working girls became a major fad among young Korean women.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.12
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• pp.1992-2005
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• 2010

Emotion directly affects consumer buying behavior. This study examines Chinese consumers' emotion elicitation process toward a U.S. apparel brand in the Chinese market. Employing a cognitive appraisal theory, this study proposed and tested a conceptual model incorporating three factors of consumer global orientation as antecedents of consumer emotion and purchase intention as a consequence of emotion. Among the ten proposed hypotheses, eight were supported. Of the three antecedents of consumer emotion, exposure to global mass media and cultural openness positively increased Chinese consumers' appraisals of a U.S. apparel brand. Unlike these two antecedents, the effects of exposure to mass migration on consumer appraisals were found to be non significant. The relationships between appraisal dimensions and positive emotion were all supported. Finally, this study confirmed that positive emotions increased Chinese consumers' purchase intentions of a U.S. apparel brand. Theoretical and managerial implications were discussed based on the findings.

• Analyses & Alternatives
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• v.5 no.1
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• pp.3-24
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• 2021

This paper introduces a multilevel item-response-theory (IRT) model as a unifying model for hypothesis testing using legislative voting data. This paper shows that a probit or logit model is a special type of multilevel IRT model. In particular, it is demonstrated that, when a probit or logit model is applied to multiple votes, it makes unrealistic assumptions and produces incorrect coefficient estimates. The advantages of a multilevel IRT model over a probit or logit model are illustrated with a Monte Carlo experiment and an example from the U.S. House. Finally, this paper provides a practical guide to fitting this model to legislative voting data.

• Journal of the Korean Mathematical Society
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• v.32 no.3
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• pp.401-413
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• 1995

This paper is concerned with the problem given below $$ (1.1) i\frac{dx}{du_1(x,\lambda)} + q1(x)u_2(x,\lambda) = \lambdau_1(x,\lambda) 0 \leq x < \infty - i\frac{dx}{du_2(x,\lambda)} + q2(x)u_1(x,\lambda) = \lambdau_2(x,\lambda), $$ $$ (2) u_2(0,\lambda) - hu_1(0,\lambda) = 0 $$ where $\lambda$ is a complex parameter and h is a non-zero complex number.