• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.124-128
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• 2009

In this study, the effect of multi-step purification or functionalization on physicochemical properties of multi-walled carbon nanotubes (MWNTs)/epoxy (EP) nanocomposites was investigated. The nanocomposites containing multi-step purified MWNTs showed a stronger influence on $T_g$ and increased in mechanical properties in comparison to nanocomposites containing the same amount of only purified MWNTs. Consequently, the multi-step purification of MWNTs led to an improvement of thermomechanical properties of nanocomposites, resulting from improving the intermolecular interaction of MWNTs in epoxy matrix resins.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.13 no.4
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• pp.437-448
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• 2000

In this study, a numerical analysis method for soil-pile interaction in frequency domain problem is presented. The total soil-pile interaction system is divided into two parts so called near field and far field. In the near field, beam elements are used lot a pile and plain strain finite elements for soil. In the far field, dynamic fundamental solution for multi-layered half planes based on boundary element formulation is adopted lot soil. These two fields are coupled using FE-BE coupling technique. In order to verify the proposed soil-pile interaction analysis, the dynamic responses of pile on multi-layered half planes are simulated and the results are compared with the experimental results. Also, various numerical analyses of piles considering different conditions of soil-pile interaction system are performed to examine the dynamic behavior of the system. It has been found that the developed method which satisfies the radiation conditions of multi-layered half planes can be applied to various structure systems effectively in frequency domain.

• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.605-612
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• 2011

In multi-center randomized clinical trial the treatment eect may be changed over centers. It is thus important to investigate the heterogeneity in treatment eect between centers. For this, uncorrelated random-eect models assuming independence between random-eect terms have been often used, which may be a strong assumption. In this paper we propose a correlated frailty modelling approach of investigating such heterogeneity using the hierarchical-likelihood method when the outcome is time-to-event. In particular, we show how to construct a proper prediction interval for frailty, which explores graphically the potential heterogeneity for a treatment-by-center interaction term. The proposed method is illustrated via numerical studies based on data from the design of a multi-center clinical trial.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.178-188
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• 2003

A study on the dynamic analysis of a tracked vehicle for mining on deep-sea bed with very soft soil is presented. An equation for the interaction between track and soft soil is employed to develop a track/soil interaction module called TVAS. The vehicle is modeled as a multi-body dynamic system using a multi-body dynamic analysis program. The developed module is incorporated into the multi-body dynamic analysis program with a user subroutine. The dynamic behavior and design of the mining vehicle on deep-sea bed is investigated.

• Korean Institute of Interior Design Journal
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• v.14 no.3 s.50
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• pp.234-242
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• 2005

Interface is a medium or channel to communicate between human and things, while interaction is the manner of communication between them. Interaction design is designing experience of user through the interaction process for human, thing, system, and space. Richard Buchanan suggests four kinds of interaction: interface (person to thing interaction), transaction (person to person interaction), human interaction (human and environment interaction) and participation (human to cosmos interaction). With digital technology, architecture and space design have made various experiments at form, function, and content of space. Space evolves from a physical container to a stage to provide narrative and create new experience to users. Since understanding users, creating experience, efficient space design, content planning, and applicable technology are required for interaction design in space, multi-disciplinary research and cooperation is needed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.289-290
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• 2010

• Journal of the Korea Computer Graphics Society
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• v.24 no.3
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• pp.11-20
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• 2018

This study proposes collaboration based multi-user interaction to provide improved presence and satisfying experience to multiple HMD users in immersive virtual reality. The core of the proposed multi-user interaction is to present the direction in which HMD users in virtual reality environment can interact through communication and collaboration with each other based on their separate roles and behaviors. Each user in the virtual collaborative environment uses a hand to interact with a virtual environment or virtual objects. Based on the basic structure, this study designs methods (synchronization and communication) that can be achieved a common goal together through communication and collaboration. Then, this study creates a virtual reality application of arcade genre that considers communication and collaboration in order to verify whether the proposed multi-user interaction provides improved presence and satisfaction experience. And, the survey experiments are conducted for participants. Through these processes, it is confirmed that the interaction in the proposed immersive virtual collaborative environments provide the presence and experience that is satisfactory to all users.

• Coupled systems mechanics
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• v.5 no.2
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• pp.145-156
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• 2016

An efficient and general numerical strategy for fluid-structure interaction problems is presented where either the fluid or the structure part are represented by nonlinear models. This partitioned strategy is implemented under the form of code coupling that allows to (re)-use previous made developments in a more general multi-physics context. This strategy and its numerical implementation is verified on classical fluid-structure interaction benchmarks, and then applied to the impact of tsunamis waves on submerged structures.

• Journal of Internet Computing and Services
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• v.6 no.1
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• pp.95-103
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• 2005

Recently researches about multi-modal system has been studied widely and actively, Such multi-modal systems are enable to increase possibility of HCI(Human-computer Interaction) realization, enable to provide information in various ways and also enable to be applicable in e-business application, If ideal multi-modal system can be realized in future, eventually user can maximize interactive usability between information instrument and men in hands-free and eyes-free, In this paper, a new multi-modal browsing system using Java RMI as communication interface, which integrated by HTML browser and voice browser is suggested and also English-English dictionary search application system is implemented as example.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.289-292
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• 2009

Injector dynamics of multi swirl injectors in an annular combustor have been investigated by LES(Large Eddy Simulation) turbulent model with MPI parallel computation technique. The present study employs the LM6000 lean premixed swirl-stabilized annular combustor. Real shape combustor is simulated in order to investigate the detail interaction mechanism among multi-injectors. The strong vortex breakdown occurs at the impinging surface between the adjacent injectors so that the complex and strong oscillatory pressure propagates inside of the combustor. Tangential pressure fluctuation mode was captured by including multi injectors in computational domain.