• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.726-739
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• 2003

A multi-dimensioanl model is being increasingly used to predict the thermo-flow field in the gas turbine combustor. This article addresses an integrated survey of modeling of the liquid spray formation and fuel distribution in gas turbine with high-shear nozzle/swirler assembly. The processes of concern include breakup of a liquid jet injected through a hole type orifice into air stream, spray-wall interaction and spray-film interaction, breakup of liquid sheet into ligaments and droplet,5, and secondary droplet breakup. Atomization of liquid through hole nozzle is described using a liquid blobs model and hybrid model of Kelvin-Helmholtz wave and Rayleigh-Taylor wave. The high-speed viscous liquid sheet atomization on the pre-filmer is modeled by a linear stability analysis. Spray-wall interaction model and liquid film model over the wall surface are also considered.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.1
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• pp.40-50
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• 2009

Knowledge-based services are largely dependent upon human-driven works. Therefore, considering human characteristics is required when modeling processes for knowledge-based services. As an emerging technology for Business Process Management, Human Interaction Management and its supportive process management can be an alternative to deal with human-driven processes. However, current HIM does not suggest concrete method for modeling conditions that are essential to realize supportive process management. And the condition modeling of HumanEdj, the only HIM software implemented, reveals the problem of complexity. As a solution, this paper suggests a fact-oriented ontological approach to process modeling. The approach uses human-friendly form of facts for condition modeling.

• Proceedings of the Korea Society of Design Studies Conference
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• 1999.10a
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• pp.28-29
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• 1999

제품을 사용한다는 것은 어떤 목적을 달성하기 위한 제품과 사용자 사이의 입력과 출력과정으로 해석할 수 있다. 이런 측면에서 제품과 사용자와의 관계를 고찰해 볼 때 최근에 부쩍 그 수가 늘어난 지능형 제품들은 이전의 제품들이 물리적이고 신체적인 자원의 투입과 이에 따른 기계적인 제품반응에 의해 사용자와 직접적이고 단순한 제어-피제어의 관계를 가졌던 것과는 달리 지적인 자원의 투입과 함께 제품으로부터 지적인 결과물을 출력받아 사용자가 이를 다시 해석해야하는 간접적이면서도 쌍방향적인 교류관계를 가진다.(중략)

• Korean Journal of Child Studies
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• v.29 no.6
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• pp.55-71
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• 2008

This study investigated parenting knowledge, interactions between mother and infant, and relationship between mother's parenting knowledge and mother-infant interaction by mothers' demographic variables. Subjects were 311 mothers. Instruments were the Knowledge of Child Development Inventory (Larsen & Juhasz, 1986) and the Assessment Profile for Early Childhood programs (Abbott-Shim & Sibely, 1987). Data were analyzed by t-test and ANOVA. Results showed (1) differences about parenting knowledge by mothers' employment status, age and education level, (2) differences in mother-infant interaction by mothers' age and education level, (3) parenting knowledge about physical development correlated positively with positive interaction, linguistic modeling, and sensitive response knowledge about linguistic and cognitive development had a large effect on positive mother-infant interaction and linguistic modeling.

• Korean Journal of Child Studies
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• v.37 no.6
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• pp.145-155
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• 2016

Objective: The purpose of this study was to investigate trajectories of child peer interaction and to compare the causal effects of their predictors, including child individual variables (i.e., gender, language ability, and cognitive ability) and teacher variables (i.e., teacher efficacy and teacher-child interaction). Methods: The participants of this study were 263 children and their teachers from the forth to sixth waves of longitudinal data from the Korean Children and Youth Panel Survey by the Korea Institute of Child Care and Education. The data was analyzed using Pearson's correlation and latent growth modeling. Results and Conclusion: The findings of this study are as follows: First, there was a linear decrease in child negative peer interaction over the course of 3 years, and significant individual differences were found in the trajectories (intercept and slope). Second, the predictors had significant casual effects on the trajectories of child negative peer interaction. The trajectories of child negative peer interaction involving girls, higher cognitive ability, and greater teacher-child interaction showed lower degree of intercept and a quicker decrease. Finally, the implications of findings are discussed.

• Economic and Environmental Geology
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• v.33 no.5
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• pp.405-415
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• 2000

This study was carried out to understand the formation of acid mine drainage (AMD) by pyrophyllite (so-called Napseok)-rainwater interaction (weathering), dispersion patterns of heavy metals, and patterns of mixing with non-polluted water in the Tongnae pyrophyllite mine. Based on the mass balance and reaction path modeling, using both the geochemistry of water and occurrence of the secondary minerals (weathering products), the geochemical evolution of AMD was simulated by computer code of SOLVEQ and CHILLER. It shows that the pH of stream water is from 6.2 to 7.3 upstream of the Tongnae mine. Close to the mine, the pH decreases to 2. Despite being diluted with non-polluted tributaries, the acidity of mine drainage water maintains as far as downstream. The results of modeling of water-rock interaction show that the activity of hydrogen ion increases (pH decreases), the goncentration of ${HCO_3}^-$ decreases associated with increasing $H^+$ activity, as the reaction is processing. The concentration of ${SO_4}^{2-}$first increases minutely, but later increases rapidly as pH drops below 4.3. The concentrations of cations and heavy metals are controlled by the dissolution of reactants and re-dissolution of derived species (weathering products) according to the pH. The continuous adding of reactive minerals, namely the progressively larger degrees of water-rock interaction, causes the formation of secondary minerals in the following sequence; goethite, then Mn-oxides, then boehmite, then kaolinite, then Ca-nontronite, then Mgnontronite, and finally chalcedony. The results of reaction path modeling agree well with the field data, and offer useful information on the geochemical evolution of AMD. The results of reaction path modeling on the formation of AMD offer useful information for the estimation and the appraisal of pollution caused by water-rock interaction as geological environments. And also, the ones can be used as data for the choice of appropriate remediation technique for AMD.

• Journal of Power Electronics
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• v.5 no.2
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• pp.83-98
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• 2005

As wind turbine technology and control has advanced over the last decade, this has led to a high penetration of wind turbines into the power system. Whether it be for a large wind turbine or an offshore wind farm with hundreds of MW power capacity, the electrical system has become more and more important in controlling the interaction between the mechanical system of the wind turbine and the main power system. The presence of power electronics in wind turbines improves their controllability with respect not only to its mechanical loads but also to its power quality. This paper presents an overview of a developed simulation platform for the modeling, design and optimization of wind turbines. The ability to simulate the dynamic behavior of wind turbines and the wind turbine grid interaction using four simulation tools (Matlab, Saber, DIgSILENT and HAWC) is investigated, improved and extended.

• Journal of Korean Institute of Industrial Engineers
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• v.8 no.1
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• pp.40-60
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• 1982

Since the first oil embargo (1973), there have been developed many different types of energy-economy interaction models based upon various aspects of energy impact mechanism. We will propose to develop an integrated energy-economy interaction analysis system for less developed countries' energy policy analysis, especially for investment analysis toward constructing energy-saving industry infrastructure ; which is based on the motivation of combined energy models by John P. Weyant. This modeling system can cover the economic growth, inter-industry transactions including production features, and process analysis of energy sector in the total network scheme of general equilibrium, so that it can give many political implications as well as the modeling concept to be used for analyzing various political issues and making decisions related to national energy environment.

• Korean Journal of Child Studies
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• v.28 no.5
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• pp.109-126
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• 2007

A sample of 322 18-month-old infants and their mothers were assessed longitudinally at 24 and 30 months. Maternal utterances and styles of linguistic interaction were measured during a 10 minute free play session. Mothers completed a vocabulary checklist for infants. Longitudinal data were analyzed by multilevel modeling. Results indicated that vocabulary increased with age of infants and the growth rate was highly predictable by the size of vocabulary at 18 months. The growth rate was strongly influenced by maternal questioning and feedback. The effect of the maternal linguistic input was constant with age. Gender differences in size of vocabulary did not vary systematically with age.

• International Journal of CAD/CAM
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• v.8 no.1
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• pp.41-44
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• 2009

This paper describes an implementation of virtual teeth modeling for a haptic dental simulation. The system allows dental students to practice dental procedures with realistic tactual feelings. The system requires fast and stable haptic rendering and volume modeling techniques working on the virtual tooth. In our implementation, a volumetric implicit surface is used for intuitive shape modification without topological constraints and haptic rendering. The volumetric implicit surface is generated from input geometric model by using a closest point transformation algorithm. And for visual rendering, we apply an adaptive polygonization method to convert volumetric teeth model to geometric model. We improve our previous system using new octree design to save memory requirement while increase the performance and visual quality.