• 한국안전학회지
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• 제16권2호
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• pp.22-26
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• 2001

The machining process on be considered as a planned interaction of the workpiece, the tool and the machine tool. In an unmanned situation, the results of this interaction are to be continuously monitored so that any changes in the machining environment on be sensed to corrective actions. In order to design the process monitoring system for unmanned manufacturing, the identification of chip formation is proposed. The system proposes the method of using acoustic emission(AE) signal analysis to identify the chip formation during cutting.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.807-813
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• 2015

교량상의 장대레일은 궤도-교량상호작용에 의해 토노반상의 장대레일에 비해 복잡한 거동을 보인다. 궤도-교량 상호작용에 영향을 미치는 요인은 온도변화와 차량하중이다. 국내 철도설계지침 KR C-08080에서는 해석 시 사용하는 물성치, 모델링 방법, 하중 및 하중 조합 방법 등에 대하여 제시하고 있다. 2014년에 KR C-08080에서 제시된 차량하중이 변경되었다. 본 연구에서는 변경된 차량하중의 영향을 평가하기 위하여 22개 교량에 대한 궤도-교량 상호작용 유한요소 해석을 수행하였다.

• 대한간호학회지
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• 제31권3호
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• pp.417-431
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• 2001

Purpose: This study was conducted to evaluate the effectiveness of the maternal role education program for primiparas in mother-infant interaction, childrearing environment, and infant development. Method: A Non-equivalent control group time-series design was used. For the intervention group, programmed parenting education focusing on mother-infant interaction, home environment for infant development, and parent counseling and support was provided via home visits or telephone for twelve months. Result: Significant differences were found in the mother-infant interaction feeding scale at one and three months, but no differences were found in the teaching scale at six and twelve months between the intervention and control groups. Also, the difference in childrearing environment (HOME) between the two groups was significant at three, six, twelve months. In addition, the intervention group showed higher GQ in the Griffiths mental development scale at three and six months. In multiple regression analysis, 22.6% to 43.6% of infant development was explained by HOME, mother-infant interaction, and previous development. Conclusion: The maternal role education program proved to be effective in promoting mother-infant interaction, organizing the childrearing environment, and fostering infant development.

• 한국산학기술학회논문지
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• 제22권4호
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• pp.563-569
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• 2021

본 연구는 ICT기업의 외국인지분율과 기업가치에 관한 연구로 외국인지분율이 기업가치에 미치는 영향을 분석하기 위하여 2011년부터 2018년까지 8개년 동안 KOSDAQ에 상장된 ICT기업 94개를 대상으로 752개의 표본을 이용하여 연구를 진행하였다. 연구결과, 외국인지분율이 증가할수록 기업가치가 증가하는 것으로 나타났다. 또한, 외국인지분율과 부채비율의 상호작용이 기업가치에 미치는 영향을 분석한 결과에서는 외국인지분율과 부채비율의 상호작용이 기업가치에 정(+)의 영향을 미치는 것으로 나타났다. 다만, 이러한 상호작용효과는 외국인지분율과 기업가치의 관계보다 통계적인 유의성이 떨어지는 것으로 나타났는데 이는 외국인 투자자들이 부채사용에 따른 감시 및 통제역할을 이미 어느 정도 수행하고 있기 때문에 외국인지분율과 부채비율의 상호작용효과가 상대적으로 작게 나타난 것으로 파악된다.

• 한국학교수학회논문집
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• 제22권2호
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• pp.133-161
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• 2019

본 연구에서는 일반 중학교 3학년 학생들의 일상적인 수업에서 집단 창의성 발현을 통해 수학적 모델링 활동을 지원한 사례를 분석하였다. 이를 위해 첫째, 선행연구 분석을 통해 사회문화적 관점에 따른 집단 창의성의 의미와 수학적 모델링의 사회문화적 특성을 확인하였다. 둘째, 4명씩 5모둠으로 구성된 한 학급에서 실험을 수행한 뒤, 집단 창의성 발현이 잘 이루어진 한 모둠의 사례에 초점을 둔 사례 연구를 수행하였다. 그 결과, 첫째, 수학적 모델링의 각 단계별로 다양한 유형의 상호작용이 나타났으며, 수학적 모델링의 단계와 발생한 상호작용의 유형에 따라 다양한 창의적 시너지가 관찰되었다. 즉, 수학적 모델링 활동에서 집단 창의성 발현이 관찰되었다. 둘째, 발현된 집단 창의성은 수학적 모델링의 각 단계의 수행을 지원하였다. 이때, 수학적 모델링의 단계와 발생한 상호작용에 따라 각기 다른 방향으로 수학적 모델링 활동을 지원하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제22권2호
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• pp.1-24
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• 2013

The main purpose of this study is to understand how the characteristics of social network services' social group can impact customer satisfaction, trust and repurchase intention. For this, this study extracts five social group factors(word of mouth effect, social interaction, collectivism, variety seeking, information seeking) based on relevant literature reviews. In addition, the study examines the moderating effects of utilitarian value on the relationships between customer satisfaction and trust and intention to repurchase. The proposed model of this study is empirically tested using survey data collected from 220 social commerce users. The results indicated that social group factors except social interaction were positively related to customer satisfaction. In addition, social group factors except social interaction and information seeking were positively related to trust. The results also showed that customer satisfaction and trust had a significant influence on intention to repurchase. The moderating effects of utilitarian value also was significant. The results of this study presented the strategic implications for social commerce firms.

• 한국소음진동공학회논문집
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• 제22권8호
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• pp.763-770
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• 2012

The free vibration characteristics of fluid-filled cylindrical shells on partial elastic foundations are investigated by an analytical method. The cylindrical shell is fully or partially surrounded by the elastic foundations, these are represented by the Winkler or Pasternak model. The motion of shell is represented by the first order shear deformation theory to account for rotary inertia and transverse shear strains. The steady flow of fluid is described by the classical potential flow theory. The fluid-structure interaction is considered in the analysis. The effect of internal fluid can be considered by imposing a relation between the fluid pressure and the radial displacement of the structure at the interface. To validate the present method, the numerical example is presented and compared with the available existing results.

• 전기전자학회논문지
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• 제22권2호
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• pp.446-454
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• 2018

In this work, we summarize the calculation processes of obtaining a scattering factor using with the equilibrium average projection scheme (EAPS), with moderately weak coupling (MWC) interaction, and obtain the line-shape formula of an electron-deformation phonon interacting system interested in the confinement of electrons by squarwell confinement potentials in quantum two dimensional system.. Through the numerical analysis, we analysis the magnetic dependence of absorption power, P(B) in several temperature and frequency difference dependence of absorption power $P({\Delta}{\omega})$, in several external field, where ${\Delta}{\omega}={\omega}-{\omega}_0$ and ${\omega}({\omega}_0)$ is the angular frequency (the cyclotron resonance frequency). The result of equilibrium average projection scheme (EAPS) in SER-MWC explains the properties of quantum transition quite well.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.897-902
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• 2001

The protein back-extraction processes were discussed from the viewpoint of the micelle-micelle interaction. Bovine serum albumin (BSA) suppressing the cluster formation of reverse micelle (positive value of ${\beta}pr)$ has the high back-extra cted fraction (Eb), but cytochrome c enhancing the formation of reverse micelle (negative value of ${\beta}pr)$ has the low back-extracted fraction, relatively. We have also examined quantitatively the effects of alcohol addition and protein solubilization on the percolation process of reverse micelle. The alcohols suppressing the formation of micellar cluster (high values of ${\beta}t)$, remarkably improved the back-extraction rates of BSA and cytochrome c. The values of ${\beta}t$, defined by the variation of percolation process, and the back-extraction behavior of proteins have a good linear correlation. These results indicate that the micelle-micelle interaction or micellar clustering plays an important role in the back-extraction process of proteins.

• Bulletin of the Korean Chemical Society
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• 제22권9호
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• pp.1009-1014
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• 2001

In aqueous mixtures of cationic OTAC (octadecyl trimethyl ammonium chloride) and anionic ADS (ammonium dodecyl sulfate) surfactants, mixed micelles were formed at low (< 0.2 wt %) total surfactant concentrations. For these mixtures mixed micelliza tion and interaction of surfactant molecules were examined. Mixed critical micelle concentration (CMC), thermodynamic potentials of micellization, and minimum area per surfactant molecule at the interface were obtained from surface tensiometry and electrical conductometry. The mixed micellar compositions and the estimation of interacting forces were determined on the basis of a regular solution model. The CMCs were reduced, although not substantial, and synergistic behavior of the ADS and OTAC in the mixed micelles was observed. The CMC reductions in this anionic/cationic system were comparable to those in nonionic/anionic surfactant systems. The interaction parameter $\beta$ of the regular solution model was estimated to be -5 and this negative value of $\beta$ indicated an overall attractive force in the mixed state.