• Composites Research
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• v.24 no.3
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• pp.31-38
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• 2011

In this paper, a novel hybrid composite shield to protect space structures from hypervelocity impact of micrometeoroid and space debris is proposed. The finite element model of the proposed shield was constructed and finite element analysis was conducted to approximate the energy absorption rate. Before the final model analysis, analysis of each component including the aluminum plate, PMMA plate, and intermediate layer of fabric was performed, verifying the finite element model of each component. The material properties used in the analyses were predicted material property values for high strain rates. The analysis results showed that, other than the fabric, the energy absorption rate of each component was in agreement. Afterwards, the finite element model of the hybrid composite shield was constructed, where it was analyzed for the restrained and unrestrained fabric boundary condition cases. Through the finite element analysis, the fiber pullout mechanism was realized for the hybrid shield with free boundary inserted fabric, and it was observed that this mechanism led to energy absorption increase.

• Textile Coloration and Finishing
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• v.1 no.1
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• pp.54-62
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• 1989

The woven fabric composed of nylon 6 filaments was treated with aqueous solutions (20, 30, 40, 50, 60%) of formic acid at 3$0^{\circ}C$ for 10 minutes under unrestrained condition, and the shrinkage behavior and some kinds of properties were examined. The shrinkages of the constituent yarns and fabric were increased with formic acid concentration, but they were lower than that of the original filaments because of fabric-structural factors. And the shrinkage of the warp was lower than that of the weft because of the residual stress from weaving process. By the restraint forces such as fabric-structural factors and residual stress, the constituent filaments were damaged partially at 60% of formic acid concentration and the degree of damage on the warp was greater than on the weft. And though the fabric count were increased overall, the spacing between the warps was decreased prior to the weft and eliminated nearly at 60% of formic acid concentration. The thickness, tensile strength, elongation, and handle value of fabric were increased overall with formic acid concentration excepting that the tensile strength for both the warp and weft directions and the elongation for the warp direction were decreased instead by the damage of yarns. But the crease recovery was decreased except the case of the weft direction at 60% of formic acid concentration.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.5
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• pp.107-116
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• 2019

Non-geometric shapes in contemporary architecture was explained from the transcendental schema of Deleuze with his abstraction theory. In this explanation, the intensity, the movement and change and the sublime were suggested as the expressional elements of the transcendental abstraction related with the artistic sensation of architecture. First, the intensity as a power of sensation which acts to the body before the recognition of brain is mainly expressed with the movement of curved lines of architectural space. Second, the movement of change is expressed as the de-centralized and de-formalized nomadic curve as the line in architectural 'smooth space' which has unrestrained orientations. Third, the sublime is expressed in the hugeness, enormousness or sometimes uncanny in void space, which could be contradictively mixed with senses of displeasure and pleasure. The sublime feelings in architecture can be emerging by rationally overcoming the unpleasant senses of contradictive spaces in architecture or urban fabric. This study has explained those expressional elements with the architectural works of Steven Holl, Frank Gehry and Zaha Hadid.