• Title/Summary/Keyword: Interaction effects

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Numerical Analysis of Hypersonic Shock-Shock Interaction using AUSMPW+ Scheme and Gas Reaction Models (AUSMPW+ 수치기법과 반응기체 모델을 이용한 극초음속 충격파-충격파 상호작용 수치해석)

  • Lee Joon-Ho;Kim Chongam;Rho Oh-Hyun
    • 한국전산유체공학회:학술대회논문집
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    • 1999.05a
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    • pp.29-34
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    • 1999
  • A two-dimensional Navier-Stokes code based on AUSMPW+ scheme has been developed to simulate the hypersonic flowfield of hypersonic shock-shock interaction. AUSMPW+ scheme is a new hybrid flux splitting scheme, which is improved by introducing pressure-based weight functions to eliminate the typical drawbacks of AUSM-type schemes, such as non-monotone pressure solutions. To study the real gas effects, three different gas models are taken into account in this paper: perfect gas, equilibrium flow and nonequilibrium flow. It has been investigated how each gas model influences on the peak surface loading, such as wall pressure and wall heat transfer, and unsteady flowfield structure in the region of shock-shock interaction. With the results, the value of peak pressure is not sensitive to the real gas effects nor to the wall catalyticity. However, the value of peak heat transfer rates is affected by the real gas effects and the wall catalyticity. The structure of the flowfield also changes drastically in the presence of real gas effects.

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Effects of a Mother-fetus Interaction Promotion Program on the Mother-infant Interaction during Feeding (모-태아 상호작용 증진 프로그램이 수유 시 모아상호작용(NCAF)에 미친 효과)

  • Han, Kyung-Ja;Kwon, Mi-Kyung
    • Child Health Nursing Research
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    • v.13 no.2
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    • pp.191-200
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    • 2007
  • Purpose: This study was conducted to develop a mother-fetus interaction promotion program aimed at enhancing the sensitivity of primiparas, and to evaluate the effects of a mother-infant play interaction. Method: Participants were recruited from OB-GY clinic with postpartum take-care center (17 mother-infant dyads for intervention group and 17 dyads for control group). Data were collected from January 18 to August 5, 2005. For the intervention group, programmed education which focused on mother-fetus interaction in the 3rd trimester was given. For the two groups, home visiting or a postpartum care center was used for data collection of the mother-infant interaction which was conducted at postpartum 1 week and 1 month. Also mother-infant interactions during feeding were videotaped and two trained observers analyzed the tapes. Results: A significant difference was found in mother-infant interaction between the two groups (postpartum 1 week, t=6.10, P=0.000, 1 month t=6.69, p=.000). For variations in mother-infant interaction in the control group, a significant difference was found in between postpartum 1 week and 1 month (t=-2.564, p=.021). In subscale analysis, interactional behavior of the infant significantly increased in both groups. Conclusion: This study showed that the mother-fetus interaction promotion program aimed at promoting mother-infant interaction increase maternal sensitivity. Therefore, this study suggests that this nursing intervention to increase maternal sensitivity to the fetus should be broadly applied with primiparas, as it can be beneficial for formation of the mother-infant relationship, and for promotion of the social, emotional, and cognitive developments of the children.

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The Effects of Infant Massage on Teacher-infant Interaction and Nursery Adaptation of Infants (영아 마사지가 교사-영아의 상호작용 및 어린이집 적응에 미치는 효과)

  • Lee, Mi Na
    • The Korean Journal of Community Living Science
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    • v.24 no.3
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    • pp.381-390
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    • 2013
  • This research is to verify the effects of infant massage on teacher-infant interaction and nursery adaptation. The subjects were 20 infants younger than one year of age, and the experimental group and the control group were randomly assigned. I developed an infant massage activity and trained an infant teacher to do it with 30-hours workshop. The massage was accomplished a total of 18 times, 3 times a week for 6 weeks. The research tools employed are the Caregiver Interaction Scale(CIS) which was developed by Arnett(1989) and employed by Kim(2009) and the Preschool Adjustment Questionaire(PAQ) which was employed by Yang(2005). They were modified and supplemented for this study to serve as a teacher rating scale. The collected data was analyzed after the experiment service through the t-verification. The results showed that the experimental group that took the infant massage scored higher than the control group in both teacher-infant interaction and nursery adaptation. Therefore, it demonstrated that infant massage has an effect on positive and permissive interaction in teacher-infant interaction and nursery adaptation.

Effects of Father's Play Beliefs on Father-Child Interaction and Child's Social Skills (아버지의 놀이신념이 부-자녀 간 상호작용과 아동의 사회적 기술에 미치는 영향)

  • Im, Ye Sul;Han, You Jin
    • Korean Journal of Child Studies
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    • v.36 no.2
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    • pp.1-16
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    • 2015
  • The purpose of this study is to investigate the effects of father's play beliefs on father-child interaction and child's social skills. The subjects were 370 fathers of 1, 2 and 3 graders of elementary schools who lived in Seoul and Gyeonggi area. The results were as follows; First, the differences were found to be significant between the whole of father's play hours, play focus beliefs, study focus beliefs and father-child interaction, and their sub-variables of disciplinary action, sensitiveness, and affectionate expression; and between the whole of child's social skills and its sub-variables of cooperative action, self-assertion and self-control. Second, the higher play focus beliefs, the more positive interaction on the child, and specifically they use much democratic disciplinary action, sensitiveness and affectionate expression. Third, as to the effect of the father's play focus beliefs on the child's social skills, father-child interaction was found to act as a partial parameter, while as to the effect of the father's study focus beliefs on the child's social skills, father-child interaction was found to act as a full parameter.

The Effects of the Home Literacy Environment, Mother's Literacy Beliefs, and Parenting Efficacy on the Interaction between Preschoolers and Mothers in Terms of Reading Picture Books (가정문해환경, 어머니의 문해신념과 양육효능감이 유아와 어머니의 그림책 읽기 상호작용에 미치는 영향)

  • Choi, Naya
    • Korean Journal of Child Studies
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    • v.33 no.6
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    • pp.109-131
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    • 2012
  • The purpose of this study was to investigate the effects of the home literacy environment, mother's literacy belief and parenting efficacy in terms of the interaction which occurs during reading picture books between mothers and preschoolers. Questionnaires from 378 5-year-olds' mothers in Seoul and Kyunggi province were analysed. The findings from the validated structural equation model constructed with these variables were as follows. First, the home literacy environment, the mother's literacy beliefs and the mother's general parenting efficacy affected the quantity, and the quality of interaction whilst reading books with preschoolers. Second, the mother's efficacy in education and communication had a direct impact on the quantity of the interaction during reading books through the mediation of the home literacy environment, and had an indirect effect on the quality of the interaction whilst reading books, respectively. Third, the mother's efficacy in communication directly accounted for the quality of the interaction which occurs whilst reading books with children.

The Interaction Effect between Fathers' Parenting and Play Participation on Emotional Regulation of Preschoolers (아버지의 양육행동과 유아의 정서조절의 관계에서 놀이참여의 상호작용 효과)

  • Jeon, Sook Hee;Lee, Hee Sun
    • Korean Journal of Childcare and Education
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    • v.12 no.5
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    • pp.115-136
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    • 2016
  • The purpose of this study was to examine the main and interaction effects of fathers' parenting and their play participation on emotional regulation of preschoolers. The participants of this study consisted of 269 preschoolers (M: 61.4 months, SD: 15.3) located in Seoul and Gyeong-gi province. The results of regression analysis revealed that; 1) Father's parenting (such as rational instruction, friendly attitude) positively predicted child's emotion regulations. 2) The interaction effects of fathers' parenting (such as parenting participation, reaction, rational instruction, friendly attitude) with their constructive play participation predicted children's emotion regulations. Namely, fathers with higher constructive play participation showed higher emotion regulations of preschoolers under father's parenting participation, reaction, rational instruction and friendly attitude. 3) The interaction effects between fathers' functional play participation and father's parenting participation predicted children's emotion regulations. Findings indicate that fathers play a role in improving children's emotion regulation by parenting. Moreover, its effects appeared more apparently when fathers participated with constructive and functional play methods. In conclusion, it is suggested that fathering and the level of play involvement may be key variables for developing young children's emotion regulation.

Numerical Analysis of Hypersonic Shock-Shock Interaction using AUSMPW+ Scheme and Gas Reaction Models

  • Lee, Joon Ho;Kim, Chongam;Rho, Oh-Hyun
    • International Journal of Aeronautical and Space Sciences
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    • v.1 no.1
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    • pp.21-28
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    • 2000
  • The flowfield of hypersonic shock-shock interaction has been simulated using a two-dimensional Navier-Stokes code based on AUSMPW+ scheme. AUSMPW+ scheme is a new hybrid flux splitting scheme, which is improved by introducing pressure-based weight functions to eliminate the typical drawbacks of AUSM-type schemes, such as non-monotone pressure solutions. To study the real gas effects, three different gas models are taken into account in the present paper: perfect gas, equilibrium flow and non equilibrium flow. It has been investigated how each gas model influences on the peak surface loading, such as wall pressure and wall heat transfer, and unsteady structure of flowfield in the region of shock-shock interaction. With the results, the value of peak pressure is not sensitive to the real gas effects nor to the wall catalyticity. However, the value of peak heat transfer rates is affected by the real gas effects and the wall catalyticity. Also, the structure of the flowfield changes drastically in the presence of real gas effects.

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A Study on the Effects of Price Discount, Product Review, and Perceived Risk and their Interaction Effects in Social Commerce (소셜 커머스에서 가격할인, 상품후기, 지각된 위험의 영향과 상호작용에 관한 연구)

  • Bang, Jounghae;Qian, Chen;Kim, Min Sun;Lee, Eun Hyung
    • Knowledge Management Research
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    • v.14 no.4
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    • pp.87-98
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    • 2013
  • Along with the recent development of Social Network Service (SNS), such as Facebook and Twitter, social commerce market is expanding rapidly. As much, understanding consumers' purchase intention in social commerce becomes important. This study attempted to investigate the factors of consumers' purchase intention, and the effects of these determinants(price discount, perceived risk and product review) on consumer's purchasing intension in social commerce networks. Also, the interaction effects between these factors on consumer's purchasing intension were studied. The results showed that the effect of perceived risk on consumer's purchase intention found to be significantly negative. The interaction effect between price discount and perceived risk, and the interaction effect between price discount and review were meaningful on consumers' purchase intention. It indicates that the important factor for consumers to purchase products in social commerce is not just price discount but perceived risk, and that review which consumers think is manipulated has negative effect on purchase intention.

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Comparison of uniform and spatially varying ground motion effects on the stochastic response of fluid-structure interaction systems

  • Bilici, Yasemin;Bayraktar, Alemdar;Adanur, Suleyman
    • Structural Engineering and Mechanics
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    • v.33 no.4
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    • pp.407-428
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    • 2009
  • The effects of the uniform and spatially varying ground motions on the stochastic response of fluid-structure interaction system during an earthquake are investigated by using the displacement based fluid finite elements in this paper. For this purpose, variable-number-nodes two-dimensional fluid finite elements based on the Lagrangian approach is programmed in FORTRAN language and incorporated into a general-purpose computer program SVEM, which is used for stochastic dynamic analysis of solid systems under spatially varying earthquake ground motion. The spatially varying earthquake ground motion model includes wave-passage, incoherence and site-response effects. The effect of the wave-passage is considered by using various wave velocities. The incoherence effect is examined by considering the Harichandran-Vanmarcke and Luco-Wong coherency models. Homogeneous medium and firm soil types are selected for considering the site-response effect where the foundation supports are constructed. A concrete gravity dam is selected for numerical example. The S16E component recorded at Pacoima dam during the San Fernando Earthquake in 1971 is used as a ground motion. Three different analysis cases are considered for spatially varying ground motion. Displacements, stresses and hydrodynamic pressures occurring on the upstream face of the dam are calculated for each case and compare with those of uniform ground motion. It is concluded that spatially varying earthquake ground motions have important effects on the stochastic response of fluid-structure interaction systems.

Proposed New Evaluation Method of the Site Coefficients Considering the Effects of the Structure-Soil Interaction (구조물-지반 상호작용 영향을 고려한 새로운 지반계수 평가방법에 대한 제안)

  • Kim, Yong-Seok
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2006.03a
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    • pp.327-336
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    • 2006
  • Site coefficients in IBC and KBC codes have some limits to predict the rational seismic responses of a structure, because they consider only the effect of the soil amplification without the effects of the structure-soil interaction. In this study, upper and lower limits of site coefficients are estimated through the pseudo 3-D elastic seismic response analyses of structures built on linear or nonlinear soil layers considering the structure-soil interaction effects. Soil characteristics of site classes of A, B, and C were assumed to be linear, and those of site classes of D and E were done to be nonlinear and the Ramberg-Osgood model was used to evaluate shear modulus and damping ratio of a soil layer depending on the shear wave velocity of a soil layer. Seismic analyses were performed with 12 weak or moderate earthquake records, scaled the peak acceleration to 0.1g or 0.2g and deconvoluted as earthquake records at the bedrock 30m beneath the outcrop. With the study results of the elastic seismic response analyses of structures, new standard response spectrum and upper and lower limits of the site coefficients of Fa and Fv at the short period range and the period of 1 second are suggested Including the structure-soil interaction effects.

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