• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4B
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• pp.637-646
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• 2010

For 40 Gb/s data transmission through electrical backplane trace up to 40 inch length on four layer fire-resistant (FR-4), we have designed the 40 Gb/s backplane channel model consisting of four channel 10 Gb/s. Simulation results show an enhancement of backplane channel characteristics excellent more than requirements specified in IEEE P802.3ba at 10 Gb/s. This paper provides a review of the structures and algorithms used in receive and adaptive equalization for 40 Gb/s backplane Ethernet. The use of this backplane channel model could achieves better receive equalizer at great data rate than 10 Gb/s.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.1
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• pp.9-18
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• 2010

There are two kinds of models in two-phase pressured drop; homogeneous flow model and separated flow model. Many previous researchers have developed correlations for two-phase pressure drop in a microchannel. Most correlations were modified Lockhart and Martinelli's correlation, which was based on the separated flow model. In this study, experiments for adiabatic liquid water and nitrogen gas flow in rectangular microchannels were conducted to investigate two-phase pressure drop in the rectangular microchannels. Two-phase frictional pressure drop in the rectangular microchannels is highly related with flow regime. Homogeneous model with six two-phase viscosity models: $Owen^{(21)}$'s, $MacAdams^{(22)}$'s, Cicchitti et ${al.}^{(23)}$'s, Dukler et ${al.}^{(24)}$'s, Beattie and ${Whalley}^{(25)}$'s, Lin et ${al.}^{(26)}$'s models and six separated flow models: Lockhart and $Martinelli^{(27)}$'s, ${Chisholm}^{(31)}$'s, Zhang et ${al.,}^{(15)}$'s, Lee and ${Lee}^{(5)}$'s, Moriyama and ${Inue}^{(4)}$'s, Qu and $Mudawar^{(8)}$'s models were assessed with our experimental data. The best two-phase viscosity model is Beattie and Whalley's model. The best separated flow model is Qu and Mudawar's correlation. Flow regime dependency in both homogeneous and separated flow models was observed. Therefore, new flow pattern based correlations for both homogeneous and separated flow models were individually proposed.

• Journal of Information Technology Applications and Management
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• v.14 no.1
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• pp.1-20
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• 2007

IT outsourcing becomes one of the important shills for managing diverse and complex information systems, SIA is considered as an one of the success factors for the successful outsourcing management. Since it helps to establish common goal and provides better visibility of trends and performance, the SLA process must go beyond mere measurement to include a methodology for the ongoing management of service levels, and for the continuous improvement of service activities, functions and processes. Despite SLA is one of the most important skills for the successful outsourcing, few studies have been conducted for academic as well as practical purpose. For this reason, The objective of this study is to develop an SLA's maturity model and empirically demonstrate how SLA's maturity level affects its Performance through SLA's maturity model. The major contributions of this study are in two areas. This study contributes to academicians as well as practitioners. First, from the academic perspectives this study tries investigating the maturity level of the SLA based on empirical data. Second, practitioners can self-test their firms' maturity level using the proposed model. The results of this study show that the SLA's maturity level affected positively SLA's performance. It is founded that the SLA's maturity level had a significant impact on SLA's performance.

• Proceedings of the Korea Contents Association Conference
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• 2004.11a
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• pp.78-83
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• 2004

In the early days, we could be provided almost internet contents without pay. It's been turning out the time we need to pay for getting some internet contents as it has become one of important media. It's already been a kind of big market. We need to develop the revenue model of character brand in the internet business. Character brand could make the internet contents on a position of advantage. We've made the revenue through using character brand and making commodities and services more valuable. We use the internet in a wide range of daily life communication. It's expected to extend. It's needed to study which kind of revenue model is existed at the moment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.163-164
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• 2006

In this paper, an analytical laser ablation model with Maxwell equation will be addressed by considering relationship between laser ablation and material. The Maxwell equation consists of four equations: two Gauss laws for electric and magnetic fields, Faraday's law, and Ampere's law. This analytical model will be calculated by employing Finite Difference Time Domain (FDTD). This method also makes it possible to simulate the laser beam propagation in a wide range of materials, such as metals, semiconductors, and dielectrics. Therefore, in this study, a numerical model for short pulse laser interaction with materials is developed, focusing on the accurate description of laser beam propagation and ablation process into the material with each pulse.

• Korean Journal of Child Studies
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• v.26 no.1
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• pp.261-278
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• 2005

The purpose of this study was to demonstrate the paths among the risk-protective factors that related to the resilience based on the Challenge Model. The subjects for this study were 209 children from divorced families in the 4th, 5th, and 6th grades of elementary schools in Seoul and Gyunggi-do. As the results, there were 28 paths which affected the resilience of children from divorced families based on the Challenge Model. The protective factors were easy temperament, problem-focused coping style, parental support, peer's support, higher socio-economic status, experiences in therapy, presence of siblings, contact with adult caretakers. The risk factors were higher grade, emotion-focused coping style, and children's gender, especially girls. This result demonstrated that each risk and protective factor not only affected resilience separately but interacted with one another.

• Journal of Mechanical Science and Technology
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• v.19 no.12
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• pp.2224-2230
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• 2005

In this study, the validity of the Eshelby-type model for predicting the effective Young's modulus and in-plane Poisson's ratio of the 2-dimensional perforated plate has been investigated in terms of the porosity size and its arrangement. The predicted results by the Eshelby-type model are compared with those by finite element analysis. Whenever the ratio of the porosity size to the specimen size becomes smaller than 0.07, the effective elastic constants predicted by finite element analysis are convergent regardless of the arrangement of the porosities. Under these conditions, the effective Young's moduli of the perforated plate can be predicted within the accuracy of $5\%$ by the Eshelby-type model, which overestimates and underestimates the effective Poisson's ratios by $10\%\;and\;6\%$ for the plates with periodically and non-periodically arranged porosities, respectively.

• Journal of the Korean Physical Society
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• v.80
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• pp.30-36
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• 2022

Holographic model of massive scalar field with its self-interaction λϕⁿ in AdS space is able to give a logarithmic scale dependence to marginal multi-trace deformation couplings on its dual conformal field theory, where λ is the self-interaction coupling of the scalar field, ϕ, and n is an integral number. In arXiv:1501.06664, the authors realize this feature by looking at bulk scalar solutions near AdS boundary imposing a specific boundary condition between the coefficients of non-normalizable and normalizable modes of the scalar field excitations. We study the same holographic model to see scale dependence of marginal deformations on the dual conformal field theory by employing completely different method: holographic Wilsonian renormalization group. We solve Hamilton-Jacobi equation derived from the holographic model of massive scalar with λϕⁿ interaction and obtain the solution of marginal multi-trace deformations up to the leading order in λ. It turns out that the solution of marginal multi-trace deformation also presents logarithmic behavior in energy scale near UV region.

• Journal of dental hygiene science
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• v.15 no.6
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• pp.807-814
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• 2015

The purpose of this study is to create a hypothetical model that explains and predicts oral health promotion behavior of adolescents by reviewing preceding literature on Pender's Health Promotion Model, and to verify the model's validity and proposed hypothesis through PLS (partial least square) structural equation model analysis. This study was cross-sectional survey consisted of self-administration questionnaires. The subjects in this study were a total of 293 alternative high school students in Jeollabuk-do Province. They were selected by convenience sampling. In alternative high school students, perceived benefit, locus of control, self-efficacy, and self-esteem had an effect on their oral health promoting behavior. As a result of the indirect effects in black is subjectively good subjective oral health, oral health related behaviors well past the more oral health promotion behavior showed a high. The prediction model of oral health promotion for adolescences, which was made using Pender's Health Promotion Model, was considered to be useful in explaining and predicting alternative high school students oral health promotion behavior.

• Journal of Korea Water Resources Association
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• v.31 no.1
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• pp.27-34
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• 1998

Groundwater simulation model suing GIS and Arc/Info Gridfunctions were used to delineate wellhead protection areas. Groundwater simulation model was developed within Arcview GIS. The model. which integrates the data input and manipulation. Process simulation. and display of the results . was developed by considering time variations of the parameters. The model was applied to the EPA data. The hydraulic distributions from the EPA data and those calculated from groundwater simulation model agree well and zone of influence from EPA data and that calculated suing GRID functions seem to be consistent. The developed model may be an efficient tool to delineate WHPA because it integrates all the processes inside the GIS.