• Wind and Structures
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• v.13 no.1
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• pp.21-36
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• 2010

A new full scale testing apparatus generically named the Wall of Wind (WoW) has been built by the researchers at the International Hurricane Research Center (IHRC) at Florida International University (FIU). WoW is capable of testing single story building models subjected up to category 3 hurricane wind speeds. Depending on the relative model and WoW wind field sizes, testing may entail blockage issues. In addition, the proximity of the test building to the wind simulator may also affect the aerodynamic data. This study focuses on the Computational Fluid Dynamics (CFD) assessment of the effects on the quality of the aerodynamic data of (i) blockage due to model buildings of various sizes and (ii) wind simulator proximity for various distances between the wind simulator and the test building. The test buildings were assumed to have simple parallelepiped shapes. The computer simulations were performed under both finite WoW wind-field conditions and in an extended Atmospheric Boundary Layer (ABL) wind flow. Mean pressure coefficients for the roof and the windward and leeward walls served as measures of the blockage and wind simulator proximity effects. The study uses the commercial software FLUENT with Reynolds Averaged Navier Stokes equations and a Renormalization Group (RNG) k-${\varepsilon}$ turbulence model. The results indicated that for larger size test specimens (i.e. for cases where the height of test specimen is larger than one third of the wind field height) blockage correction may become necessary. The test specimen should also be placed at a distance greater than twice the height of the test specimen from the fans to reduce proximity effect.

• Journal of Family Relations
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• v.21 no.1
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• pp.123-141
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• 2016

Objective: This study examined correlates of residential proximity between parents and non-coresident married children. A majority of existing studies on intergenerational living arrangement has focused on exploring factors that are associated with intergenerational coresidence only, despite an increasing number of parents and children who do not live together but close by. Because residential proximity facilitates frequent contacts and support exchanges between the two generations, it is important to understand its correlates. Method: The data were drawn from first wave of the Korean Longitudinal Study of Ageing (KLoSA, 2006), a nationally representative sample of adults 45 years or older and their spouses. The analytic sample consisted of 3,950 parents with 10,946 non-coresident married children. Both regression with robust standard errors and sibling fixed effects regression models were estimated using the reg and xtreg procedures in STATA. Results: Younger, less depressed, and more physically impaired parents lived closer to at least one of their married children (within a 30-minute distance by public transportation). Fathers (compared to mothers), parents living in cities (compared to those living in rural areas), parents with at least one co-resident child or fewer numbers of married children tended to have at least one married child living nearby. With regard to child characteristics, married children who were less educated, homeowners, and had more children lived closer to their parents. Also, sons (compared to daughters) lived in closer distance to their parents. Conclusion: Overall, findings suggest that intergenerational residential proximity may primarily be motivated by the childcare needs of married children or parents' needs for assistance with functional impairment. Also, the traditional patrilineal norms of intergenerational support may still be a critical factor in residential decisions as observed in the difference between married sons and daughters in proximity to their parents.

• Journal of Family Relations
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• v.23 no.2
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• pp.111-131
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• 2018

Objectives: This study examined the effects of residential proximity to adult children on the mental and physical health of middle-aged and older parents. The study also evaluated whether the parental age and gender of the adult child in closest proximity to the parent might moderate the association. Method: Data were drawn from five waves of the Korean Longitudinal Study of Aging(2006-2014). The analytic sample consisted of 7,359 parents aged 45 or older who had at least one non-coresidential adult child aged 19 or older. The analyses were conducted by estimating a series of fixed effects models while adjusting for the nested structure of the data. Results: The results showed that first, a closer distance between an adult child and the parent was generally associated with the parent experiencing a decrease in depressive symptoms. Yet, the mental health benefit was smaller for parents aged 65 years or older whose closest living adult child was a son. Second, a closer distance was observed to affect chronic illness only among middle-aged parents (aged 45 to 64). When the closest living adult child was a daughter, the middle-aged parent experienced deterioration in their chronic illness. On the other hand, the opposite pattern was observed when the closest living adult child was a son. Conclusions: The parental age and gender of the adult child in closest proximity to the parent might have varying effects on parents' health. A closer distance between an adult child and their parent has a positive impact on the mental health of the parent as a whole, whereas the effect of living closer was mixed in relation to the parental physical health.

• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.1-10
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• 2009

This study describes the electron beam lithography pattern fabrication using the proximity effect correction. When electron beam exposes into electron beam resist, the beam tends to spread inside the substance (forward scattering). And the electron beam reflected from substrate spreads again (back scattering). These two effects influence to distribution of the energy and give rise to a proximity effect while a small pattern is generated. In this article, an electron energy distribution is modeled using Gaussian shaped beam distribution and those parameters in the model are computed to solidify the model. The proximity effect is analyzed through simulations and appropriate corrections to reducing the proximity effect are suggested. It is found that the proximate effect can be reduced by adopting schemes of dose adjustment, and the optimal dose is determined through simulations. The proposed corrected proximity effect correction is proved by experiments.

• Progress in Superconductivity
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• v.12 no.2
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• pp.110-113
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• 2011

We have grown a Nb/Gd bilayer on a$SiO_2$/Si substrate by using a DC magnetron sputtering system, which was fabricated in situ with silicon stencil masks. In order to investigate proximity effect of the Nb/Gd bilayer, we used a planar tunnel junction with an AlOx tunnel barrier by oxidizing the Al ground electrode at the bottom. A $Co_{60}Fe_{40}$ backing of Al was deposited so as to reduce the superconductivity of the Al, ensuring a normal counterelectrode. With a 50-nm-thick Nb layer, we have measured dI/dV (dynamic conductance) by varying the thickness of Gd, which can reveal the density of states (DOS) of the Nb/Gd bilayer as a function of the Gd thickness resulting from the proximity effect of a superconductor/ferromagnet bilayer (S/F). The SF proximity effect in Nb/Gd will be discussed in comparison to our previous results of the CoFe/Nb, Ni/Nb and CuNi/Nb proximity effect; Gd is expected to show different effects since Gd has f-electrons, while CoFe, Ni, and CuNi have only d-electrons. Our studies will focus on the triplet correlation in a superconducting pair.

• Korean Journal of Legislative Studies
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• v.23 no.2
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• pp.147-177
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• 2017

Although a number of empirical studies found that political ideology plays a significant role in Korean elections, they entirely rely on cross-sectional data analysis. In contrast to previous research, this study investigates the effects of ideology in the 2012 Korean presidential election through standard panel data analysis. Specifically, using "EAI Panel Study, 2012", the effects of ideology on both candidate evaluation and vote choice were examined via fixed effects, random effects, and pooled regression analysis. And the results from applying the two most popular models of ideological voting, the proximity model and the directional change model were also compared. The results show that candidate evaluations and vote choice during the election (April, 2012- December, 2012) were significantly influenced by the ideological difference between voters and candidates, independent from partisanship and other standard socio-demographic factors. And this ideological voting during the election seems better captured by the directional change model than by the proximity model.

• Wind and Structures
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• v.18 no.4
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• pp.443-456
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• 2014

A popular modern architectural form for tall buildings is two (or more) towers which are structurally linked through such features as a shared podium or sky-bridges. The fundamental features of the wind loading and the structural links of such buildings can be studied by measuring load components on the individual unlinked towers along with their correlations. This paper describes application of dual high frequency force balance (DHFFB) in a wind tunnel study of the base wind loading exerted on generic tall twin buildings in close proximity. Light models of two identical generic tall buildings of square plan were mounted on DHFFB and the base wind loading exerted on the buildings was simultaneously acquired. The effects of the relative positions of the buildings on the correlations and coherences involving loading components on each building and on the two buildings were investigated. For some relative positions, the effects of the building proximity on the wind loading were significant and the loading was markedly different from that exerted on single buildings. In addition, the correlations between the loadings on the two buildings were high. These effects have potential to significantly impact, for example, the modally-coupled resonant responses of the buildings to the aerodynamic excitations. The presented results were not meant to be recommended for direct application in wind resistant design of tall twin buildings. They were intended to show that wind loading on tall buildings in close proximity is significantly different from that on single buildings and that it can be conveniently mapped using DHFFB.

• Korean Journal of Child Studies
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• v.27 no.2
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• pp.153-165
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• 2006

This study examined moderating effects of mother's support and community environment on relationships between after school self-care and problem behaviors. Subjects were 579 3rd and 6th grade elementary school children. Major findings were positive relationships between after school self-care and problem behaviors. Neither gender differences nor grade differences were found in the relationships between after school self-care and problem behaviors. Moderating effects of care by relatives or neighbors on mother's support was shown in the relationships between after school self-care and internal problem behaviors. Moderating effects of proximity to harmful facilities were found in relationships between after school self-care and external problem behaviors.

• 한국초전도학회:학술대회논문집
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• v.15
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• pp.29-29
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• 2005

• Progress in Superconductivity and Cryogenics
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• v.21 no.4
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• pp.13-18
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• 2019

Superconducting junctions of topological insulator (TI) are expected to host Majorana bound state, which is essential for developing topological quantum information devices. In this study, we fabricated Josephson junctions (JJs) made of Sb-doped Bi2Se3 TI nanoribbon and PbIn superconducting electrodes. In the normal state, the axial magnetoresistance data exhibit periodic oscillations, so-called Aharonov-Bohm oscillations, due to a metallic surface state of TI nanoribbon. At low temperature of 1.5 K, the TI JJ reveals the superconducting proximity effects, such as the critical current and multiple Andreev reflections. Under the application of microwave, integer Shapiro steps are observed with satisfying the ac Josephson relation. Our observations indicate that highly-transparent superconducting contacts are formed at the interface between TI nanoribbon and conventional superconductor, which would be useful to explore Majorana bound state in TI.