• Fashion & Textile Research Journal
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• v.1 no.4
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• pp.387-392
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• 1999

The effects of the ratio of warp diameter to filling diameter (${\beta}$-ratio) and warp thread crash on the crimp factor and the yarn curvature were studied theoretically in this paper. The models of 2/2 twill fabric derived square cloth and sinusoidal curved cloth were used for the theoretical analysis. The crimp factors (C) for the models were given theoretically as follows; (1) Derived square cloth(general equation for b) $$C=\frac{(1+{\beta})({\theta}-sin{\theta})}{(1+{\beta})sin{\theta}+{\alpha}}$$ (2) Sihusoidal curved cloth $$C=\frac{(1+{\beta})sin{\theta}\[1+\{\frac{{\pi}(1-cos{\theta})}{4sin{\theta}}\}^2\]+{\alpha}}{(1+{\beta})sin{\theta}+{\alpha}}-1$$ The curvatures(${\kappa}$) for the models were given theoretically as follows; (1) Derived square cloth $${\kappa}=\frac{2}{d_w+d_f}$$ (2) Sinusoidal curved cloth $${\kappa}=\|{^{\;\;\prime\prime} \atop r}(s)\| \\ where \;s=\frac{p^'}{{\pi}}\(u+\frac{k^2u}{4}+\frac{k^2}{8}sin2u\)$$.

• Advanced Composite Materials
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• v.16 no.4
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• pp.361-376
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• 2007

Disposing of conventional fiber-reinforced polymers (FRPs) poses an environmentally challenging problem. Disposal of FRPs by combustion discharges carbon dioxide in the air because the resin of FRPs is made of fossil fuel. When they are disposed of in the ground, FRPs remain semipermanently without decomposing. In response to these problems, green composites are now being developed and are extensively studied as a material that produces a lower environmental burden. In this paper, green composites using kenaf fiber yarn bundles and PLA (poly(lactic acid)) are fabricated and their tensile properties are evaluated in the experiment. The tensile Young's modulus of all of the laminations is larger than that of PLA alone and the tensile strength of some laminations is larger than that of PLA alone. In particular, the value of UD composite of $0^{\circ$ shows double the tensile strength of PLA alone. Furthermore, the molding conditions for fabricating with a hot press are investigated and the heat resistant tensile properties of green composites are also reported.

• Carbon letters
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• v.13 no.4
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• pp.191-204
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• 2012

Carbon nanotubes (CNTs) have exceptional mechanical, electrical, and thermal properties compared with those of commercialized high-performance fibers. For use in the form of fabrics that can maintain such properties, individual CNTs should be held together in fibers or made into yarns twisted out of the fibers. Typical methods that are used for such purposes include (a) surfactant-based coagulation spinning, which injects a polymeric binder between CNTs to form fibers; (b) liquid-crystalline spinning, which uses the nature of CNTs to form liquid crystals under certain conditions; (c) direct spinning, which can produce CNT fibers or yarns at the same time as synthesis by introducing a carbon source into a vertical furnace; and (d) forest spinning, which draws and twists CNTs grown vertically on a substrate. However, it is difficult for those CNT fibers to express the excellent properties of individual CNTs as they are. As solutions to this problem, post-treatment processes are under development for improving the production process of CNT fibers or enhancing their properties. This paper discusses the recent methods of fabricating CNT fibers and examines some post-treatment processes for property enhancement and their applications.

• Fashion & Textile Research Journal
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• v.18 no.6
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• pp.733-745
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• 2016

This paper provides a review of wearable textile strain sensors that can measure the deformation of the body surface according to the movements of the wearer. In previous studies, the requirements of textile strain sensors, materials and fabrication methods, as well as the principle of the strain sensing according to sensor structures were understood; furthermore, the factors that affect the sensing performance were critically reviewed and application studies were examined. Textile strain sensors should be able to show piezoresistive effects with consistent resistance-extension in response to the extensional deformations that are repeated when they are worn. Textile strain sensors with piezoresistivity are typically made using conductive yarn knit structures or carbon-based fillers or conducting polymer filler composite materials. For the accuracy and reliability of textile strain sensors, fabrication technologies that would minimize deformation hysteresis should be developed and processes to complement and analyze sensing results based on accurate understanding of the sensors' resistance-strain behavior are necessary. Since light-weighted, flexible, and highly elastic textile strain sensors can be worn by users without any inconvenience so that to enable the users to continuously collect data related to body movements, textile strain sensors are expected to become the core of human interface technologies with a wide range of applications in diverse areas.

• International Commerce and Information Review
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• v.9 no.2
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• pp.161-182
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• 2007

The objective of this paper is to examine the competitiveness of Korean export firms in EU market. In this study, market share index, RCA index, trade specialization index, and market competitiveness index were used as an analytical tool. On the market share index, Korea had a large market share in the SITC section 7(machinery and transport equipment) market in EU. On the RCA index, Korea appeared to have high export competitiveness in the electrical machinery, apparatus and appliances, n.e.s.(not elsewhere specified[stated]), and electrical parts thereof (77), travel goods, handbags and similar containers(83), textile yarn, fabrics, made-up articles, n.e.s., and related products(65), and iron and steel(67) division. On the trade specialization index, however, Korea appeared to tend to decline generally. On the market competitiveness index, Korea appeared to have competitive advantage in the iron and steel(67), machinery specialized for particular industries(72), office machines and automatic data-processing machines(75), electrical machinery, apparatus and appliances, n.e.s., and electrical parts thereof(77), road vehicles(78), and other transport equipment(79) division; but in 29 divisions, the index indicates that Korean firms' competitiveness was low. Finally, the authors discuss the implications of these findings and offer directions for future study.

• Journal of Fashion Business
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• v.5 no.1
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• pp.131-144
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• 2001

The purpose of this study is to examine the type of stitch and designs of knitwears using handcraft ornament techniques. This paper will also go on to develop and merchandize high value generated by design development. Knit is largely divided into weft knit stitch and warp knit stitch which are respectively woven by weft knitting machine and warp knitting machine. For clothing, circular knit and flat knit are frequently used while plain stitch, rib stitch and purl stitch are perceived as the basic stitches. Denbigh stitch, cord stitch, atlas stitch, which belong to tricot stitch, are the basic of warp knit stitch. There are also numerous fancy fabrics adapting the previously mentioned stitches and these are made into solid pattern and yarn dyed pattern. The handcraft ornament techniques in knitwears design are embroidery, beads, sequin, stone, printing, applique and fringe, etc. By applying these techniques thus creative expression, which cannot be expressed in other fashion items, is feasible. The women's knitwears are tries by mixed and various techniques, develope to high value knitwears, escaping from simple and practical items.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.670-686
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• 2017

MapReduce (MRV1), a popular programming model, proposed by Google, has been well used to process large datasets in Hadoop, an open source cloud platform. Its new version MapReduce 2.0 (MRV2) developed along with the emerging of Yarn has achieved obvious improvement over MRV1. However, MRV2 suffers from long finishing time on certain types of jobs. Speculative Execution (SE) has been presented as an approach to the problem above by backing up those delayed jobs from low-performance machines to higher ones. In this paper, an adaptive SE strategy (ASE) is presented in Hadoop-2.6.0. Experiment results have depicted that the ASE duplicates tasks according to real-time resources usage among work nodes in a cloud. In addition, the performance of MRV2 is largely improved using the ASE strategy on job execution time and resource consumption, whether in a multi-job environment.

• Fibers and Polymers
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• v.6 no.1
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• pp.66-71
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• 2005

The surface evenness and texture are closely related with the irregularity of yam thickness. Besides, yam thickness variation has an important role to influence the yam performance and the textile process efficiency. Thus, the information not only on the yam thickness, but also on the short- term irregular characteristics that have not been known before is required for enhancing the qualities of textile products. This paper reports the results of a study about the yam thickness and its variation for various types of yam on the basis of a new measurement system applying a laser slit beam as a light source. The new method delivers effective information on the irregularity. The analysis of the measured signal confirms that the visual shade created by the yam doubling and twisting can be measured and the yam thickness characteristics can be represented by corre­lograms. Depending on yam types, correlograms have different shapes and can be approximated to an exponentially decaying function with or without fluctuating magnitude. In addition, the effective information on the yam irregularity can be influ­enced by the sampling length interval of the measuring device used for tests.

• Journal of the Korean Home Economics Association
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• v.25 no.2
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• pp.31-38
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• 1987

This paper aims to examine the velocity of water absorption of cotton, hemp, and T/C fabrics sized by rice, wheat, potato, corn flour and pp.V.A.. Experimental variables such as the concentration of sizing agents, the moisture regain of unsized fabrics and the ironing temperature showed the following results. 1. When the fabrics were sized, the velocity of water absorption increased according to the order of corn, rice, potato, wheat flour and pp.V.A. for cotton fabrics, of corn, potato, rice, wheat flour and pp.V.A. for hemp fabrics, and of corn, wheat, rice, potato flour and pp.V.A. for T/C fabrics; corn flour showed the highest velocity of water absorption and pp.V.A. did the lowest among all the others mentioned above. 2. The higher fabric density, the higher velocity of water absorption. The finer the count of fabric yarn, the higher velocity of water absorption. 3. The material of sized fabrics most affected the velocity of water absorption than other factors of those. 4. To a certain extent, the higher the concentration of sizing agent, the higher the velocity of water absorption. 5. The fabrics with moisture regain of 20% before sizing showed the highest velocity of water absorption. 6. The ironing temperature after sizing fabrics mentioned below showed the highest velocity of water absorption; 180$^{\circ}C$ for cotton, 200$^{\circ}C$ for hemp, and 160$^{\circ}C$ for T/C fabrics.

• Journal of Korea Game Society
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• v.10 no.3
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• pp.103-111
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• 2010

In this paper, an procedural approach to photorealistic rendering of woven fabric material is proposed. Previously proposed procedural approaches to fabric rendering have the disadvantage that the rendering result is not sufficiently realistic. In order to enhance the realism, researchers employed example-based approaches. However, those methods have serious disadvantage that they require huge amount of storage for the various reflectance properties of diverse materials. The proposed method can express the reflectance on weft and warp yarns by alternating the anisotropic reflectance on yarns. In addition, we propose the proposed method procedurally models the bumpy yarn structure of woven fabric to obtain plausible rendering results. The proposed method can efficiently reproduce realistic virtual fabric without any reflectance data sets.