• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.67-74
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• 2006

The ship plating is generally subjected to combined in-plane load and lateral pressure loads. In-plane loads include axial load and edge shear, which are mainly induced by overall hull girder bending and torsion rf the vessel. Lateral pressure is due to water pressure and cargo. These load components are not always applied simultaneously, but more than one can normally exist and interact. Hence, for more rational and safe design rf ship structures, it is of crucial importance to better understand the interaction relationship of the buckling and ultimate strength for ship plating under combined loads. Actual ship plates are subjected to relatively small water pressure except for the impact load due to slamming and panting etc. The present paper describes an accurate and fast procedure for analyzing the elastic-plastic large deflection behavior up to the ultimate limit state of ship plates under combined loads. In this paper, the ultimate strength characteristics of plates under axial compressive loads and lateral pressure loads are investigated secondary buckling behavior through ANSYS elastic-plastic large deflection finite element analysis with varying lateral pressure load level.

• Korean Journal of Materials Research
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• v.5 no.8
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• pp.979-987
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• 1995

This study has been investigated the Influence of layer thickness on the mechanical properties of cross laminated carbon fiber/epoxy composites. And also the difference of mechanical properties between cross laminated composites of unidirectional prepreg and fabric prepreg has been investigated. Experimental results are showed that the Interlamina Shear Strength(ILSS) of cross laminated carbon fiber/epoxy composites decreased with increasing thickness of unit ply and the decree of delamination in the laminated composites increased as ILSS decreased. Fracture toughness and impact values were found to increase as delamination occurs to some extent in the laminated composites. It Is also shown thats mechanical properties of cross laminates from unidirectional prepreg were better than those of cross laminates from fabric prepreg.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.21-26
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• 2003

Develop and need design application of carbon sex design concept that consider plasticity in elastic design concept until now. To Place that is representative construction of hull in this research rain deflection pattern analysis technique and grandeur increment method such as general load type increment law and displacement type increment law and Newton-Raphson method increment body law to use jointly compare. Specialty. through analysis by initial deflection pattern. examined closely carbon set conduct of place by initial deflection pattern. Applied thin plate structure which receive compressive load used ANSYS that analysis method is mediocrity finite element analysis program to save complicated conduct that effect that conduct after initial buckling and conduct after secondary buckling get in the whole construction is very big and such and grandeur increment law presumes complicated rain fan shape conduct in bifurcation point specially.

• Composites Research
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• v.35 no.2
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• pp.61-68
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• 2022

Composite materials have been used in aerospace industry and many applications because of many advantages such as specific strength and stiffness and corrosion resistance etc. However, it is vulnerable to impacts, these impact lead to formation of cracks in composite laminate and failure of structures. In this paper, we analyzed Mode I fracture toughness of Carbon/Epoxy laminates using acoustic emission signal. DCB test was carried out to analyze Mode I failure characterization of Carbon/Epoxy laminates, and AE sensor was attached to measure AE signal induced by failure of specimen. Fracture toughness was calculated using cumulative AE energy and measured crack length using camera. The calculated fracture toughness was applied in FE model and the result of FE analysis compared with DCB test results. The results show good agreement with between FEM and DCB test results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.89-93
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• 2002

One of the primary factors like plate structure in ship is redundancy structure that is comparable with ocean structure and frame structure. The more component material becomes buckling collapsed locally the less structure stiffness becomes accordingly. As a result, by increasing the load distribution of my other subsidiary structure continually component member collapses, therefore the structure could be in danger of collapse. So, in order to interpret this phenomenon precisely, the study on boundary condition of the ship's plate and post-buckling analysis must be considered In this study, the rectangular plate is compressed by the in-plane load Buckling & Ultimate strength characteristics are applied o be the elasto-plasticity large deformation by ansys code with F.E.M method On this basis, elasto-plasticity of the plain plate are investigated. This study proved elasto-plasticity behaviour of the ship's plate in accordance with boundary condition based on the series analysis in case of the compressive load operation

• Composites Research
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• v.28 no.2
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• pp.70-74
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• 2015

In this paper, carbon nanotubes (CNTs) and micro glass bubbles (GBs) have been incorporated into a polyamide6 (PA6) matrix to impart thermoelectric properties. The spaces created in the matrix by GBs allows the formation of "segregated" CNT network. The tightly bound CNT network, if controlled properly, can serve as a conductive path for electron transport, while prohibiting phonon transport, which would provide an ideal configuration for thermoelectric applications. The CNTs and GBs were dispersed in a nylon-formic acid solution using horn sonication followed by coagulation in deionized water, and nanocomposite panels were fabricated using a hot press. The performance of nanocomposite panels was evaluated from thermal and electrical conductivities and Seebeck coefficient, and a thermoelectric figure of merit as high as 0.016 was achieved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3627-3632
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• 2015

We investigated mechanical, rheological and electrical properties of graphite/PP/LCP composites for a bipolar plate of the polymer electrolyte membrane fuel cell. The composites containing very low molecular weighted PP showed much higher electrical conductivity compared with other thermoplastics. This was attributed to the enhanced dispersion of graphite particles due to the low viscosity of the PP. The conductivity of the composites was increased in a great extent by incorporation of small amount of carbon nano tube (CNT). However, the acid treated CNT which contains oxygen atoms did not increase the conductivity of the composite. From this result, it is concluded that the CNT has higher affinity with non polar polymer. The composite with low molecular weighted PP provided good processability so that the composites can be processed by an injection molding while the mechanical strength is deficient compared to other polymers. In order to reinforce the low mechanical property, LCP/PP was used as a binder and the graphite/PP/LCP composite showed the higher conductivity and moderate mechanical strength maintaining suitable processability.

• Polymer(Korea)
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• v.30 no.1
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• pp.90-94
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• 2006

An electrospinning process was used to fabricate poly(methyl methacrylate) (PMMA) nanofibers embedding multi-walled carbon nanotubes(MWNTs). SEM images showed that the nanofiber surface and structural morphology depended on solvent types (dimethyl formamide, chlor-form and toluene) and carbon nanotube contents (0.5 and $3.0\;wt\%$). Nano-fiber alignments could be controlled by adjusting the electrodes configuration at collector sites. Relationship between carbon nanotube and PMMA nanofiber was studied with radius of gyration of polymer chain and carbon nanotube sizes. As the carbon nanotube content ratio increased, the number of bead increased.

• Journal of the Korean Society of Marine Environment & Safety
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• v.10 no.2 s.21
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• pp.41-47
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• 2004

Plate has cutout inner bottom and girder and Door etc. in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and freight movement, piping etc.. Because cutout‘s existence is positioning in this place, and, elastic bucking strength by load causes large effect in ultimate strength. Therefore, perforated plate elastic bucking strength and ultimate strength is one of important design criteria to decide structural elements size at early structure design step of a ship. Therefore, we need reasonable & reliable design formula for elastic bucking strength of the perforated plate. The author computed numerically ultimate strength change about several aspect ratios, cutout dimension, and plate thickness by using ANSYS Finite element analysis code based on finite element method in this paper.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.129-135
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• 2004

Plate has cutout inner bottom and girder and floor etc in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and change of freight, piping etc. Because cutout's existence gnaws in this place, and, elastic budding strength by load rouses large effect in ultimate strength. Therefore, perforated plate elastic budding strength and ultimate strength is one of important design criteria which must examine when decide structural elements size at early structure design step if ship. Therefore, and, reasonable elastic budding strength about perforated plate need design ultimate strength. Calculated ultimate strength change several aspect ratioes and cutout's dimension, and thickness in this investigation. Used program applied ANSYS F.E.M code based on finite element method