• Journal of Mechanical Science and Technology
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• v.20 no.11
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• pp.1891-1897
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• 2006

In this study, a new model to predict the effective elastic constants of composites with spherical fillers is proposed. The original Eshelby model is extended to a finite filler volume fraction without using Mori-Tanaka's mean field approach. When single filler is embedded in the matrix, the effective elastic constants of the composite are computed. The composite is in turn considered as a new matrix, where new single filler is again embedded in the matrix. The predicted results by the present model with a series of embedding procedures are compared with those by Mori-Tanaka, self-consistent, and generalized self-consistent models. It is revealed through parametric studies such as stiffness ratio of the filler to the matrix and filler volume fraction that the present model gives more accurate predictions than Mori-Tanaka model without using the complicated numerical scheme used in self-consistent and generalized self-consistent models.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.295-298
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• 2005

High temperature deformation behavior of $\alpha\;and\;\beta$ phase of Ti-6Al-4V was investigated within the framework of a self-consistent approach at various temperature ranges. To examine the flow behavior of u-phase, Ti-7.0Al-1.5V alloy was used, whose chemical composition is close to that of the $\alpha$ phase in Ti-6Al-4V at hot working temperatures. The flow stress of $\beta$ phase was predicted by using self-consistent approach. The flow stress of $\alpha$ phase was higher than that of $\beta$ phase above $750^{\circ}C$, while the $\beta$ phase revealed higher flow stress than a phase at $650^{\circ}C$. It was found that the relative strength and strain rate ratio between $\alpha\;and\;\beta$ phase significantly varied with temperature. From this approach, the mode for grain matrix deformation was proposed as a mixed type of both iso-stress and iso-strain rate modes.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.775-778
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• 2003

In this paper, we report our quantum mechanical approach for the analysis of FinFET in a self-consistent manner. The simulation results are carefully investigated for FinFET with an electrical channel length(Leff) of 30nm and with a fin thickness(Tsi) of 10～35nm. We also demonstrated the differences in the simulations for the classical and quantum-mechanical simulation approaches, respectively. These simulation results also imply that it is necessary to solve the coupled Poisson and Schrodinger equations in a self-consistent manner for analyzing the sub-30nm MOSFETS including FinFET.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.238-243
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• 1993

A self-consistent-field Green's matrix method for the calculation of electronic properties of chemisorbed system is devised and applied to the methanol on copper(110) surface. The method is based on CNDO Hartree-Fock approximation. Contour integration in the complex energy plane is used for an efficient calculation of the charge-density bond-order matrix. The information on each fragment prior to chemisorption is efficiently used and a small number of iterations are needed to reach the self-consistency. The changes of density of states and other quantities of methanol due to chemisorption are consistent with reported experimental results.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.10
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• pp.887-894
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• 2013

Effective thermal conductivity of nanofluids has been predicted by using generalized self-consistent model and modified Eshelby model, which have been used for analysis of material properties of composites. A nanolayer between base fluid and nanoparticle, one of key factors for abrupt enhancement of thermal conductivity of nanofluids, is included in the analysis. The effective thermal conductivities of the nanofluid predicted by the present study show good agreement with those by models in the literature for the nanolayer with a constant or linear thermal conductivity. The predicted results by the present approach have been confirmed to be consistent with experiments for representative nanofluids such as base fluids of water or ethyleneglycol and nanoparticles of $Al_2O_3$ or CuO to be validated.

• Journal of Korean Academy of Nursing
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• v.33 no.8
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• pp.1161-1170
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• 2003

Purpose. The purpose of this study was to examine the effects of a rehabilitation program on hope and self-efficacy in a sample of homeless adolescent substance abusers at a halfway house in Seoul, Korea. Methods. Five residents of a halfway house were provided with a 16-week rehabilitation program based on a cognitive-behavioral approach. To evaluate the effectiveness of the program, this study used a single-case experimental design with the variables - hope and self-efficacy - being measured at pre-, post-, and follow-up tests. Results. While three participants showed considerable positive changes in hope and self-efficacy after the program, two participants did not show any positive changes. Despite this lack of consistent patterns in the effectiveness of the rehabilitation program, there was a qualitative change in social status (such as academic and work status) for the participants at the follow-up test. Conclusion. A rehabilitation program based on a cognitive-behavioral approach may improve the hope and self-efficacy of homeless adolescent substance abusers at a halfway house and help them to reintegrate into society.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.1
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• pp.1-6
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• 2002

A new closed-form expressions to calculate frequency-dependent distributed inductance and the associated distributed series resistance of single interconnect on a lossy silicon substrate (CMOS technology) are presented. The proposed analytic model for series impedance is based on a self-consistent field method and the vector magnetic potential equation. It is shown that the calculated frequency-dependent distributed inductance and the associated resistance are in good agreement with the results obtained from rigorous full wave solutions and CAD-oriented equivalent-circuit modeling approach.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.89-94
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• 2008

This paper deals with the method of self-equilibrium stress mode analysis of cable dome structures. From the point of view of analysis, cable dome structure is a kind of unstable truss structure which is stabilized by means of introduction of prestressing. The prestress must be introduced according to a specific proportion among different structural member and it is determined by an analysis called self-equilibrium stress mode analysis. The mathematical equation involved in the self-equilibrium stress mode analysis is a system of linear equations which can be solved numerically by adopting the concept of Moore-Penrose generalized inverse. The calculation of the generalized inverse is carried out by rank factorization method. This method involves a parameter called epsilon which plays a critical role in self-equilibrium stress mode analysis. It is thus of interest to investigate the range of epsilon which produces consistent solution during the analysis of self-equilibrium stress mode.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.748-756
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• 2006

We propose a genome-scale clustering approach to identify whole genome relationships using the functional groups given by the Kyoto Encyclopedia of Genes and Genomes Orthology (KO) database. The metabolic capabilities of each organism were defined by the number of genes in each functional category. The archaeal, bacterial, and eukaryotic genomes were compared by simultaneously applying a two-step clustering method, comprised of a self-organizing tree algorithm followed by unsupervised hierarchical clustering. The clustering results were consistent with various phenotypic characteristics of the organisms analyzed and, additionally, showed a different aspect of the relationship between genomes that have previously been established through rRNA-based comparisons. The proposed approach to collect and cluster the metabolic functional capabilities of organisms should make it a useful tool in predicting relationships among organisms.

• The Journal of Information Systems
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• v.28 no.4
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• pp.27-47
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• 2019

Purpose The study examined the key factors influencing the formation mechanism of SNS addiction. Based on the use and gratification theory, we considered relationship maintenance, perceived enjoyment, and self-expression as main desires to induce SNS addiction. The characteristics of SNS users were also considered as major factors affecting SNS addiction. In particular, self-control and subjective well-beings were considered to be prevention factors that could reduce SNS addiction, while SNS relational intimacy was considered to be a facilitator that would increase SNS addiction. Design/Methodology/Approach A structural equation modeling (SEM) method was used to test the theoretical framework based on a sample of 224 Facebook users who have used it more than 6 months. Confirmation factor analysis was conducted to check the reliability, convergent validity, and discriminant validity. Findings Relationship maintenance had a significant effect on self-disclosure intention and SNS addiction, respectively. Perceived enjoyment was significantly related to self-disclosure intention, while it was insignificantly associated with SNS addiction. However, self-expression was not significantly related to both self-disclosure intention and SNS addiction. Consistent with our expectations, both self-control and subjective well-beings had negative effects on SNS addiction. The analysis results found that SNS relational intimacy was positively related to SNS addiction.