• Advances in nano research
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• v.15 no.2
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• pp.91-104
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• 2023

Development of thin carbon nanotubes (CNTs) nanoliquid film over the rough surface of a horizontal rotating disk is investigated by considering symmetric roughness either along the azimuthal or radial directions. The disk surface is either heated or cooled axisymmetrically from below. The effects of single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs) are analyzed on the film thinning process with different types of base liquids. Closed form solutions for velocity and temperature field are obtained for small values of Reynolds number whereas the numerical solution is derived for moderate values of Reynolds number. It is found that fluid retention / depletion takes place when the roughness is symmetric along the azimuthal / radial directions. It is also seen that the film thinning rate enhances for MWCNTs compare to SWCNTs. Further it is found that two different heat transfer regions exits within the flow domain depending on the fact that heat is transferred from disk to liquid film and vice-versa.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.176-181
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• 2024

The desktop-level 3D printing machines makes it easier for independent designers to produce collectible models. Desktop 3D printers that use FDM (Fused Deposition Modeling) technology usually use a minimum nozzle diameter of 0.4mm. When using FDM printers to make Gunpla models, Thin slice structures are prone to slicing errors, which lead to deformation of printed objects and reduction in structural strength. This paper aims to analyze the printing model that produces errors, control a single variable among the three variables of slice layer height, slice wall thickness and filament type for comparative testing, and find a way to avoid gaps. To provide assistance for using FDM printers to build models containing thin-walled structures.

• Structural Engineering and Mechanics
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• v.4 no.4
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• pp.462-465
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• 1996

• Proceedings of the Korean Society of Potoscience Conference
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• 2005.06a
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• pp.73-73
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• 2005

• Structural Engineering and Mechanics
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• v.29 no.3
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• pp.351-354
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• 2008

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.42-42
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• 2010

We have characterized the previously undescribed parameters for engineering the electrical properties of single-walled carbon nanotube (SWCNT) films for technological applications. The surface tension of the top coating passivation material and matching coefficients of thermal expansion for the substrate and carbon nanotube network are two crucial parameters for the fabrication of reliable and highly conductive single-walled carbon nanotube network thin films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.278-278
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• 2010

We have characterized the previously undescribed parameters for engineering the electrical properties of single-walled carbon nanotube (SWCNT) films for technological applications. The surface tension of the top coating passivation material and matching coefficients of thermal expansion for the substrate and carbon nanotube network are two crucial parameters for the fabrication of reliable and highly conductive single-walled carbon nanotube network thin films.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.539-540
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• 2010

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.575-584
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• 2006

In this paper, a shear-flexible finite element model is developed for the buckling analysis of axially loaded, thin-walled composite I-beams. Based on an orthogonal Cartesian coordinate system, the displacement fields are defined using the first-order shear-deformable beam theory. The derived element takes into account flexural shear deformation and torsional warping deformation. Three different types of beam elements, namely, the two-noded, three-noded, and four-noded beam elements, were developed to solve the governing equations. An inverse iteration with shift eigenvalue solution was used to solve the resulting linearized buckling problem. A parametric study was conducted to show the importance of shear flexibility and fiber orientation on the buckling behavior of thin-walled composite beams. A good agreement was obtained among the proposed shear-flexible model, other results available in literature, and the finite element solution.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.422-425
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• 2008

Recently, electronic products and related parts are required to have thin thickness because of small form factor. To go with the trend, LGP(light guide plate) of LCD BLU(Liquid Crystal Display Back light unit: It is one of kernel parts of LCD) for cell phone has the thickness of 0.3 mm and the battery case of cell phone has 0.25 mm. Accordingly, high speed injection molding is required to make products which have thin thickness. High speed injection molding means that the resin is injected into the cavity at higher than normal speed avoiding short shot. In the case of hydro-mechanical high speed injection machine, it requires the design for hydraulic unit to make high injection speed and the design for control unit to control hydraulic unit. In the present paper, we concentrated on the molding stability of hydro-mechanical high speed injection machine to make an LGP of 0.3 mm thickness.