• Coupled systems mechanics
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• v.5 no.3
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• pp.235-254
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• 2016

A numerical model for fluid-structure interactions (abbr. FSI) is presented in the context of sloshing effects in movable, partially filled tanks to improve understanding of interactions between the fluid and the dynamics of a tank flexibly attached to a vehicle. The purpose of this model is to counteract the penalizing impact of the added mass effect on classical partitioned FSI coupling scheme: the proposed investigation is based on an added mass corrected version of the classical strongly coupled partitioned scheme presented in (Song et al. 2013). Results show that this corrected version systematically allows convergence to the coupled solution. In the rare cases where convergence is already obtained, the corrected version significantly reduces the number of iterations required. Finally, it is shown that the convergence limit imposed by added mass effect for the non-corrected coupling scheme, is directly dependent on the aspect ratio of the fluid domain and highly related to the precision order of the temporal discretization scheme.

• Korean Journal of Child Studies
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• v.9 no.1
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• pp.47-61
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• 1988

The primary purpose of this study was to investigate the relation between paternal self-esteem, child-rearing behaviors and child's self-esteem. The secondary purpose was to examine whether there were significant relational differences according to child's sex. 272 dyads consisting of fifth and sixth grade children in elementary school and their measured by the Self-Esteem Inventory (for children), the Self-Esteem Scale (for fathers), and the Iowa Parent Behavior Inventory: Father form. Pearson's r., F-test, and Ducan's multiple range test were used for data analysis. Paternal self-esteem was significantly associated with 'parental involvement', 'reasoning guidance', and 'intimacy'. Paternal self-esteem was positively correlated with girl's self-esteem. Child's self-esteem was positively related to 'parental involvement', 'limit setting', 'responsiveness', 'reasoning guidance' and 'intimacy'. In sex differences, only boy's self-esteem wasn't related to paternal 'limit setting'. Boys' self-esteem was strongly related to 'parental involvement', and girls' self-esteem was strongly related to 'reasoning guidance'.

• Journal of the Korean Mathematical Society
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• v.53 no.2
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• pp.315-329
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• 2016

In the setting of continuous logic, we study atomless probability spaces and atomless random variable structures. We characterize ${\kappa}$-saturated atomless probability spaces and ${\kappa}$-saturated atomless random variable structures for every infinite cardinal ${\kappa}$. Moreover, ${\kappa}$-saturated and strongly ${\kappa}$-homogeneous atomless probability spaces and ${\kappa}$-saturated and strongly ${\kappa}$-homogeneous atomless random variable structures are characterized for every infinite cardinal ${\kappa}$. For atomless probability spaces, we prove that ${\aleph}_1$-saturation is equivalent to Hoover-Keisler saturation. For atomless random variable structures whose underlying probability spaces are Hoover-Keisler saturated, we prove several equivalent conditions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.802-807
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• 2007

We have developed red phosphorescent top emission organic light-emitting diodes with transparent metal cathodes deposited by using thermal evaporation technique. Phosphorescent guest molecule, BtpIr(acac), was doped in host CBP for the red phosphorescent emission, Ca/Ag, Ba/Ag, and Mg/Ag double layers were used as cathode materials of top emission devices, which were composed of glass/Ni/2TNATA(15 nm)/${\alpha}$-NPD(35 nm)/CBP:BtpIr(acac)(40 nm, 10%)/BCP(5 nm)/$Alq_3$(5 nm)/cathodes. The optical transparencies of these metal cathodes strongly depend on underlying Ca, Ba, and Mg layers. These layers also strongly affect the electrical conduction and emission properties of the red phosphorescent top emission devices.

• Journal of the Korean Home Economics Association
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• v.38 no.9
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• pp.1-18
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• 2000

The purpose of this study is to investigate the Korean value about family and kinship in urban and rural families. For this purpose, we surveyed 716 subjects with structured questionnaires in Seoul and 593 subjects in rural areas. From this survey, we reached the following conclusions: 1) In urban families, most of the respondents are found not to support familism, materialism, boy preference, and they show an ambivalence about the child value in the viewpoint of the reward and the cost. 2) Most of the respondents in rural families are found to support familism, materialism, and rewardable child value. But, as the same as urban families, they don't show boy preference. 3) Comparing urban families with rural families, the latter are found to support familism more strongly. And there are sleight differences in boy preference significantly. On the other hand, urban families are found to show costly chad value more strongly.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.8 s.227
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• pp.968-975
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• 2004

Nanofluids have anomalously high thermal conductivities at very low fraction, strongly temperature-dependent and size-dependent conductivities, and three-fold higher critical heat flux than that of base fluids. Traditional conductivity theories such as the Maxwell or other macroscale approaches cannot explain why nanofluids have these intriguing features. So in this paper, we devise a theoretical model that accounts for the fundamental role of dynamic nanoparticles in nanofluids. The proposed model not only captures the concentration and temperature-dependent conductivity, but also predicts strongly size-dependent conductivity. Furthermore, we physically explain the new phenomena for nanofluids. In addition, based on a proposed model, the effects of various parameters such as the ratio of thermal conductivity of nanofluids to that of a base fluid, volume fraction, nanoparticle size, and temperature on the thermal conductivities of nanofluids are investigated.

• The Pure and Applied Mathematics
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• v.10 no.4
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• pp.265-271
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• 2003

Let $CS_\alpha(\beta)$ denote the class of normalized strongly $\alpha$-close-to-convex functions of order $\beta$, defined in the open unit disk $\cal{U}$ of $\mathbb{C}$${\mid}arg{(1-{\alpha})\frac{f(z)}{g(z)}+{\alpha}\frac{zf'(z)}{g(z)}}{\mid}\;\leq\frac{\pi}{2}{\beta}(\alpha,\beta\geq0)$ such that $g\; \in\;S^{\ask}$, the class of normalized starlike unctions. In this paper, we obtain the sharp Fekete-Szego inequalities for functions belonging to $CS_\alpha(\beta)$.

• Communications of the Korean Mathematical Society
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• v.12 no.1
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• pp.193-201
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• 1997

The paper presens results on the perturbation problem of invariant manifolds of differential equations. It is well-known that if there is a pseudohyperbollic structure on an invariant manifold then one is strongly indestructible. The set of strongly inderstructible invariant manifolds is wider than the set of persistent (normally hyperbolic) manifolds. The following theorem is main result of the paper: if the condition of transversality holds on an invariant manifold, except, possibly, for the non-degenerate strong sources and non-degenerate strong sinks, then there is the pseudohyperbolic structure on the invariant manifold. From this it follows the conditions for the indestructibility of locally non-unique invariant manifolds. An example is considered.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.04a
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• pp.102-106
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• 1997

Grinding has difficulty in satisfying the qualitative knowledge based on the skilled expert as well as quantitative data for all user. Design of grinding database is based on the frame-based model for utilizing the empirical and qualitative knowledge. Inthis paper, basic strategy to develop the grinding database by frame-based model, which is strongly dependent upon experience and intuition, frame-base model, which is strongly dependent upon experience and intuition, is described. Design of grinding database is based on the frame-based model for utilizing the ambiguous knowledge and inference is accomplised by the object-oriented paradigm system.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.7 no.2
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• pp.31-35
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• 1993

The radial density distributions of the positive column of strongly modulated low -pressure gas discharges in mercury - rare gas mixtures at 10 tom pressure have been studied theoretically. The current was modulated inusoidally with a modulation depth of 50%. Calculations have shown that the radial profile of the excited atoms is ditferent form 0th Bessel function $J_0$(2.4r/R) and the invertion of the radial distribution of the excited atom can occur at some frequency. The hybrid method of FDM and 2nd order Runge-Kutta meth od is used for solving differenzial equations.