• Journal of The Korean Astronomical Society
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• v.37 no.1
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• pp.1-14
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• 2004

Basic idea of Randall-Sundrum brane world model I and II is reviewed with detailed calculation. After introducing the brane world metric with exponential warp factor, metrics of Randall-Sundrum models are constructed. We explain how Randall-Sundrum model I with two branes makes the gauge hierarchy problem much milder, and derive Newtonian gravity in Randall-Sundrum model II with a single brane by considering small fluctuations.

• Fibers and Polymers
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• v.4 no.4
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• pp.151-155
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• 2003

The abrasion behavior of three kinds of warp knitted fabrics, which are normally used for upper sole of footwear, was evaluated. We measured the changes of mechanical and structural properties of each sample as abrasion cycle increased. Each sample showed similar trends in compression and surface properties but there were significant differences in abrasion rate among the samples. The mechanical properties showed remarkable differences with directions. The frictional coefficient (MIU) of fabric surface increased at the beginning of abrasion and decreased as abrasion cycles increased. The weight and thickness of the fabric linearly decreased with abrasion cycles. The surface roughness (SMD) and the compressional resilience (RC) decreased as abrasion cycles increased while compressional energy (WC) increased.

• Fibers and Polymers
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• v.6 no.1
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• pp.49-54
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• 2005

The purpose of this study has been to investigate the effect of dilation on the some mechanical properties of several types of warp-knitted vascular grafts. The structures of warp knit vascular grafts used in the experiments were reverse locknit, locknit, and Tricot. Various mechanical properties of these grafts were determined using devices developed for the purpose. Clinical data obtained were compared with experimental results of warp knit vascular grafts. The most important mechanical properties are found to be creep extension, bursting strengths, and compliance. Preliminary results indicate that vascular grafts are non-compliant and exhibit creep which is predictive of the long term dilation that has been noted in the clinical results. It is found that there is a positive correlation between experimental data and clinical results for at least the grafts tested.

• Fashion & Textile Research Journal
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• v.12 no.4
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• pp.494-499
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• 2010

Knitted fabrics are very popular for their numerous advantages such as greater comfort, attractive garment appearance, better fit on the body, etc. In this study, we investigated the mechanical properties and abrasion property of warp knitted fabrics for footwear which treated with several softeners to improve abrasion resistance. The antistatic softener among the various softeners showed high improvement in abrasion resistance. Among the mechanical properties with treating conditions, WT (tensile energy), G (shear stiffness), B (bending rigidity) increased as treating timeincreased. But the other mechanical properties were little changed with treating concentration.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.222-227
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• 1999

The weavability and bleaching of ramie/silk mixture fabrics were examined. When silk fiber was used as warp or weft in the mixture fabrics, the weaving properties became higher than that of ramile fabrics. Especially, the highest weavabiliy of mixture fabrics was obtained when used as warp silk fiber. The whiteness of ramie and tussah fiber treated with hydrogen peroxide, bleaching agent. was increased up to about 80% without significant changes of tenacity and elongation. As the increase of bleaching agent and treatment time, the whiteness of mixture fabrics was increased and the yellowness was decreased. Also, as the whiteness of mixture fabrics increased, the drape stiffness in warp direction was decreased but crease recovery was increased.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.259-262
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• 2003

Fabric hand is ultimately a subjective response to physical stimuli, but there are clearly practical advantage in the development and commercial trading of textile fabrics to be gained from the replacement of the traditional subjective tactile assessment by an objective measurement evaluation method. Moreover, the reliable objective measurement method for warp knitted fabrics have not developed yet, despite their increasing importance. (omitted)

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.26-34
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• 2015

The angle of attack of a cambered otter board in a bottom trawl was estimated using a three-dimensional semi-analytic treatment of a towing cable (warp) system that was applied to the field experiments of a bottom trawl obtained by the Scanmar system. The equilibrium condition of the horizontal component and vertical component of forces was used to the three forces acting on the otter board in the horizontal plane. Those forces were the force on the warp at the bracket, hydrodynamic lift and drag forces on the otter board and the force on the hand rope attached just behind the otter board. Also the equilibrium of moment about the front edge of the otter board was used to find out the angle of attack of the cambered otter board. When the warp length was 120m and 180m long and the towing speed was between 1.23 and 1.90 m/s, the estimated angle of attack of the cambered otter board was ranged between $26.1^{\circ}$ and $29.6^{\circ}$, respectively, though the maximum lift force was at the angle of attack $22.6^{\circ}$. The angle of attack of the otter board was tended to increase weakly with the longer length of warp (180 m) at the same towing speed in the experiment.

• Science of Emotion and Sensibility
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• v.7 no.4
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• pp.25-33
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• 2004

This study surveys the fabric surface properties such as mean value of the friction coefficient(MIU), mean deviation of the friction coefficient(MMD) and mean deviation of surface roughness(SMD) due to warp and weft tension differences using KES-FB system. For this purpose, fabric is designed as 5 harness Satin weave using 75d/36f warp and 100d/192f weft polyester filaments, and is woven by OmegaR rapier loom by Textec Co.Ltd and Picanol-GTXR rapier loom by Picanol Co.Ltd respectively. These grey fabrics are processed on the same dyeing and finishing processes. The fabric surface properties according to the weaving looms are analysed with warp and weft weaving tensions. And also surveyed the difference of fabric surface properties according to the fabric positions such as center and each edge of fabrics for the sensitive garment.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.173-179
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• 2010

In this study, we determine the stretch and shrinkage properties of conjugated yarns. The shrinkage(%) and elasticity(%) were determined by applying twist conditions of 0, 350, 800, 1000, 1200, 1400, 1600, 2000 T/M (twisting per meter). It is found that the shrinkage(%) and elasticity(%) gradually decreased with increasing T/M. Especially the elasticity(%) dramatically decreased over 1400 T/M condition. In contrast, it is showed that the handle and drapery properties decreased below 1000 T/M, which indicates that the optimal T/M condition could be 1000~1400. The effect of shrinkage(%) and elasticity(%) with different steam setting temperatures (60, 70, 80 and $90^{\circ}C$) was also determined. The shrinkage(%) decreased with increasing setting temperature, while the elasticity not changed. In this context, the optimal steam setting temperature could be $80^{\circ}C$ because it is not easy to weave with the yarns which was set below $80^{\circ}C$. The elasticity(%) decreased with increasing the density of warp and weft. To produce soft handle, excellent drapery and good stretch fabrics, the warp density needs to be reached by 90% of the ideal warp density. In the case of NaOH treatments to the fabrics, the elasticity(%) increased with increasing weight reduction. Therefore, this study have demonstrated that the conjugated yarns with core yarn and the SDY CD(cation dyeable spindraw yarn) as an effect yarn would be appropriate to produce excellent mixture-yarn, which displays clean appearance, good handle and excellent elasticity, The optimized conditions are as follows; 1000~1200 twist per meter, $80^{\circ}C$ steam setting temperature, 90% of ideal warp density and relaxation condition treated with 5g/l NaOH concentration.

• Journal of the Korean Society of Costume
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• v.55 no.4 s.94
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• pp.95-106
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• 2005

The purpose of this study was to research the design methods to express jacquard design using CAD. For this study, two design patterns were divided; in addition, each design pattern is applied to two different weaving types, single woven fabric and double well cloths. As a result, 16 samples were produced by applying 4 design methods (warp shrunk as half size design/weft shrunk as half size design - A, warp shrunk as half size design/weft original size design - B, warp original size design/weft shrunk as half size design - C, warp original size design/weft original size design - D) to the two design patterns with the two weaving types. The result of this study can be summarized as follows. 1. The most delicate design method was Method D. However, Method B which took half the time less than Method D was almost as delicate as the Method D on the surface. 2. Method B was judged as a considerably efficient method for time and cost. 3. Method D was considered as most suitable for elaborate parts and delicate lines. However, it was considered uneconomical since it took the longest time. 4. Mettled A took 2.5 times less time than Method D. Therefore, Method A was more applicable to producing high density design. 5. Method C is not considered as a useful method as it showed rough surface and took long time by applying high design zoom except intentional design.