• Korea-Australia Rheology Journal
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• v.16 no.2
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• pp.101-108
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• 2004

The hemodynamics behavior of the blood flow is influenced by the presence of the arterial stenosis. If the stenosis is present in an artery, normal blood flow is disturbed. In the present study, the characteristics of pulsatile flow in the blood vessel with stenosis are investigated by the finite volume method. For the validation of numerical model, the computation results are compared with the experimental ones of Ojha et al. in the case of 45％ stenosis with a trapezoidal profile. Comparisons between the measured and the computed velocity profiles are favorable to our solutions. Finally, the effects of stenosis severity and wall shear stress are discussed in the present computational analysis. It can be seen, where the non-dimensional peak velocity is displayed for all the stenosis models at a given severity of stenosis, that it is exponentially increased. Although the stenosis and the boundary conditions are all symmetric, the asymmetric flow can be detected in the more than 57％ stenosis. The instability by a three-dimensional symmetry-breaking leads to the asymmetric separation and the intense swirling motion downstream of the stenosis.

• Journal of the Korean Ceramic Society
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• v.52 no.1
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• pp.41-47
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• 2015

Celadon shards from Gangjin and Buan were analyzed for their color, chemistry and microstructures. They exhibited similar chromatic characteristics in a $CIEL^*a^*b^*$ analysis. All of the glazes assessed showed comparable compositional areas, while the bodies from Gangjin shards had higher $RO_2$ concentrations. A high degree of similarity was also noted in the microstructures of the glaze and bodies from both regions. Anorthite crystals appeared in the glaze layer, and phase separation behavior developed around these crystals. This may have been caused by the glaze chemistry and the sintering process given the lengthy heating and cooling time. A Raman analysis indicated higher isolated $SiO_4$ unit ($Q_0$) values for the Buan samples. This can stem from the higher firing temperature or the longer sintering process.

• Proceedings of the Korean Geotechical Society Conference
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• 1987.06a
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• pp.51-80
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• 1987

In this studys a numerical analysis on the defomation of foundation layer was carried out by indroducing joint element. The method using the joust element between adj assent different materials has been originally developed for rock behavior(Goodman, et al. 1968) . The application of this method to the interface between the footing and soil layer proved satisfactory(Ghaboussi p et at. 1973). Authors tried to obtain the deformation of rrcompound foundation layerg", which vertically or horizontally or both consists of the natural(or intact) soft clay layer and the layer improved artificially in order to get high stiff-fness with replacement or chemical treatment to reduce the excessively detrimental settlemellt or lateral displacement in case of banking or building the civil structure on the soft layer. The joint conditions were classified into three categories : contacts sliding and separation. By coupling "JOINT" as a subroutine into multi-purpose code for the finite element method of the foundatlion daveloped by authors on the assumption that shearing and normal displacement can not be coupledl which terms pinon-dilatant" and by selecting modified Cam-clay modeIP the deformation analysis was performmed. The results using joint element were compared with those secured without introduction of joint element Nain results analized are as follows : 1. For the prediction of settlement and lateral desplacement, the result due to joint element was evaluated larger, which was regarded safe. 2. For the determination of ultimate bearing capacetyi the value using joint element appeared smaller by 20%, which was also safe.

• Human Ecology Research
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• v.53 no.1
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• pp.29-47
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• 2015

The purpose of this study is to conceptualize the definition of school readiness specific to the context of the Republic of Korea. The school readiness test can be used as basic data to enable early childhood educational institutes to determine the general readiness of preschoolers and provide support to fit individual characteristics. For this purpose, six stages of the school readiness development process were considered, that is, draft development, primary preliminary survey, primary expert verification, secondary expert verification, secondary preliminary survey, and main survey. In the main survey, tests were conducted using the school readiness final draft targeting 344 preschoolers living in Seoul and Gyeonggi-do. The item discrimination power analysis and factor analysis for the examination area and question area were also conducted. Consequently, a test tool was developed on the basic of the results obtained, consisting of 129 items in the five areas of knowledge, function, adaptation, tendency, and attitude. The knowledge area was divided into general, linguistic, and mathematical knowledge, and the function area into fine motor function, basic living ability, expressive function, and gross motor function. The adaptation area was classified into adaptation activity, separation anxiety, maladaptive behavior, and environment adaptation; the tendency area into learning tendency; others understanding, and individual tendency, and the attitude area into rule compliance and life habits.

• Macromolecular Research
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• v.9 no.3
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• pp.150-156
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• 2001

Polystyrenes(PS) were grafted onto polypropylene(PP) in the PP solution by ultrasonic irradiation-initiated polymerization of styrene. The resulting products consisted of mixtures of homopolymers and PP-PS copolymer because of the homopolymerization of styrene itself and copolymerization with PP. The dependency of the designated polymerization on sonication times was investigated to monitor the evolution lion of the copolymerization. Formation of the PP-PS copolymer was confirmed by FTIR analysis of the reaction products after a proper separation procedure of free PS and PP-PS copolymer. It was found that the tendency for the formation of PP-PS copolymer was closely related with the phase behavior of the PP/styrene mixture which was also influenced by sonication time. In order to verify the effectiveness of the PP-PS copolymer as a compatibilizer for PP/PS blend, melt mixing of PP/PS/PP-PS was performed in a batch mixer. During the mixing, the average torque was higher for the blend containing PP-PS copolymer influencing compatibilization. In accordance with the results from FRIR analysis and torque measurement, the PS domain size remarkably decreased in the PP/PS/PP-PS blend.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.226-226
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• 2010

Microstructure, magnetic and transport properties of as-deposited electron-doped $La_{1-x}Ce_xMnO_3$ and hole-doped $La_{1-x}Ce_xMnO_3$ films prepared by pulse laser deposition, with x = 0.1 and 0.3, have been investigated. The microstructural analysis reveals that the $La_{1-x}Ce_xMnO_3$ films have a column-like microstructure and a strip-domain phase with a periodic spacing of about 3c, which were not found for the $La_{1-x}Ce_xMnO_3$ ones. At the same time, the experimental results manifest that there is no fundamental difference in the magnetic and the transport properties between electron- and hole-doped manganite films, except the appearance of ferromagnetic response in the low-doped $La_{0.9}Ce_{0.1}MnO_3$ film at temperatures above the Curie point. The observed magnetic behavior, typical for the Griffiths-like phase, for this film is explained by the percolation mechanism of the ferromagnetic transition and by the presence of strip-domain phase which stimulates the magnetic phase separation.

• Nuclear Engineering and Technology
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• v.26 no.4
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• pp.562-569
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• 1994

In this study improvement of transient analysis model, KOTRAC, for the passive reactor has been performed. In the KOTRAC, mixture drift flux model is adopted to simulate thermal hydraulic behavior, which can simulate ECCS injection in the passive plant. However, there is a difficulty to handle complete phase separation phenomena due to the near-zero density, which may occur in the pressurizer surge line or horizontal flow paths. In this study, a couple of model changes to over-come Courant limit feilure has been examined. One of key features is to substitute flow distribution parameters with Ishii's correlation. Corrected results are nil compared to those of RELAP/MOD3 analysis.

• Journal of Music and Human Behavior
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• v.4 no.2
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• pp.18-40
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• 2007

The purpose of this study was to verify the influence of musical activities on social and emotional behavior of infants, through providing musical activities to the infants who were cared in a nursery and observing the interactions between peer group, or a therapist and an infant derived during them. The subject is 24 infants who are under 2 years of age(25~36months) at two nurseries located in Bundang area, and 13 infants among them are randomly assigned as study group and 11 infants as control group. Pretest and posttest about social and emotional behavior are performed, and ITSEA developed by Brggs-Gowan and Carter(2001) and amended by Shin Ji Yeon(2004) was used as an evaluation tool. Infants' changes of interaction behaviors during musical play were also analyzed quantitatively and qualitatively, and for the analysis, infant's social play behavior examination tool developed by Holloway and Reichhart-Erickson(1988) was adopted. Based on time sampling method, each item of this tool was evaluated. Each session was performed for 15 minutes, and 60 times of analysis about interactions per session was conducted at every 15 seconds. The analysis result was showed with a table and a graph, and described qualitatively about behavior changes. When compared social and emotional positive behavior average figures and negative behavior average figures between study group and control group, this study showed that the positive behavior figure of study group was increased and the negative behavior figure was decreased. While concentration and empathy among positive behaviors increased meaningfully, aggression, defiance, separation anxiety and rejection to new things among negative activities also decreased meaningfully. The conclusion of this study is as follows. First, interactions with peers or a therapist based on music and musical experience make an effect on strengthening positive behavior among social and emotional behavior and decreasing negative behavior. Second, music has influence on negative behaviors more than positive behaviors of an infant, and produces a good effect on sub behaviors of negative behaviors specially.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.205-219
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• 2018

The purpose of this study was to analysis of food adaptation and dietary behavior of marriage migrant women in according to their acculturation type, and find out their relationship. The survey was conducted by well-trained researchers using questionnaires translated into English, Chinese and Vietnamese. Food adaptional score was the highest in the assimilation type, and the separation type was the lowest. Dietary behavioral score in daily intake of milk and dairy foods was the highest in the assimilation type. There were positive correlations occurred between food adaptional score and dietary behavioral score, and also, between food adaptional score and assimilation score. Analysis of structural equation models shows that only assimilation affects food adaptational score, and food adaptational score affects the improvement of dietary behavior. In conclusion, marriage migrant women's positive attitude of new cultures, assimilation, might help them not only adapt to new cultures, but food adaptation and right dietary behaviors.

• Earthquakes and Structures
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• v.20 no.1
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• pp.55-70
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• 2021

In urban cities, buildings were built in the neighborhood, these buildings influence each other through structure-soilstructure interaction (SSSI) and seismic pounding due to limited separation distance in-between. Generally, the effects of the interaction between soil and structure are disregarded during seismic design and analysis of superstructure. However, the system of soil-base adversely changes structural behavior and response demands. Thus, the vibration characteristics plus the seismic response of a building are not able to be independent of those in adjacent buildings. The interaction between structure, soil, and structure investigates the action of the attendance of adjacent buildings to the others by the interaction effect of the sub-soil under dynamic disturbances. The main purpose of this research is to analyze the effects of SSSI and seismic pounding on the behavior of adjacent buildings. The response of a single structure or two adjacent structures with shallow raft base lying on soft soil are studied. Three dimensions finite element models are developed to investigate the effects of pounding; gap distance; conditions of soil; stories number; a mass of adjacent building and ground excitation frequency on the seismic responses and vibration characteristics of the structures. The variation in the story displacement, story shear, and story moment responses demands are studied to evaluate the presence effect of the adjacent buildings. Numerical results acquired using conditions of soil models are compared with the condition of fixed support and adjacent building models to a single building model. The peak responses of story displacement, story moment, and story shear are studied.