• Structural Engineering and Mechanics
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• v.22 no.6
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• pp.665-683
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• 2006

The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatly influenced by the properties of constitutive materials, the laminate structures, and load conditions etc, accompanied by many uncertainty factors. So the reliability study on FRP is an important subject of research. Many achievements have been made in reliability studies based on the probability theory, but little has been done on the roles played by fuzzy variables. In this paper, a fuzzy reliability model for FRP laminates is established first, in which the loads are considered as random variables and the strengths as fuzzy variables. Then a numerical model is developed to assess the fuzzy reliability. The Monte Carlo simulation method is utilized to compute the reliability of laminas under the maximum stress criterion. In the second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of the fact that there may exist a series of states between the failure state and the function state, a fuzzy assumption for the structure state together with the probabilistic assumption for strength parameters is adopted to construct the GFRM of composite materials. By defining a generalized limit state function, the problem is converted to the conventional reliability formula that enables the first-order reliability method (FORM) applicable in calculating the reliability index. Several examples are worked out to show the validity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivity analysis shows that some of the mean values of the strength parameters have great influence on the laminated composites' reliability. The differences resulting from the application of different failure criteria and different fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, and can provide an effective and synthetic method to evaluate the reliability of a system with different types of uncertainty factors.

• Journal of the Korean Society of Costume
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• v.51 no.1
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• pp.5-20
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• 2001

The purpose of this study suggest the fashion of communication for 21th century fashion. Especially, Memphis fashion have the possibility of communicating through objects. The results of this study are as follows : First, Memphis idea is to make design into a sophisticated, conscious instrument of communication. As the Memphis fashion points out : design is an extraordinary tool for communicating because its intrinsic characteristic is the fact that it is used and distributed anyway, even without communicating anything. The Memphis fashion is trying to connect design and industry to the broader culture within which fashion moves. Second, Using different materials provides not only new structural Possibilities. but - above all - new semantic and metaphoric possibilities, order modes of communication, another language, and even a change of direction, broadening of perspective, appropriation and digestion of new values and the concomitant rejection of traditional structures that renewal always Involves. The memphis fashion works on the fabric of contemporaneity (lurex yarn, latex, chrome metal and steel) and contemporaneity means computers, electronics, a new awareness of the body. mass exercise and tourism. Third, color in Memphis has never been an ideological vehicle. As with decoration it is born tilth the design, forming an integral part of the structure. It alters the objects molecules. It works as a mass, as an intrinsic feature of a certain form and volume. The Memphis fashion was realized the introduction of ultramodern science into such experimental and creative implementation as optical motive, brilliancy of colour of electronic medium in audition to metallic fabric and high technical synthetic fiber. A color tilth pop culture connotations that weaver between technological allusions and Mcdonald's.

• Analytical Science and Technology
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• v.13 no.5
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• pp.573-583
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• 2000

Activated carbon fibers (ACFs) were prepared from various precursors of plantic, synthetic, and mixed fabrics of viscous rayon and cotton. Their adsorption performances of phenol and methylene blue in aqueous phase were evaluated through their adsorption isotherms, adsorption rates and breakthrough curves. The two adsorbates showed type I adsorption isotherm on ACFs. Adsorption rates to ACFs were 100 fold faster than to GAC. The effective diffusion coefficients of the adsorbates in ACFs were twenty fold greater than in GAC. The ACFs removed completely ten organic pollutants from a prepared water specimens through the 2nd column of a natural filtration method where 50 L of the water samples were treated.

• Journal of the Korean Society of Clothing and Textiles
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• v.1 no.1
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• pp.25-29
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• 1977

The warmth retentivity of natural and syntheic waddings as bedding stuff, and further, the machanism of heat transmission through conduction, radiation and convection were analysed. The materials used were cotton, silk, and wool as natural waddings, and polyamide, polyester, regular acrylic, conjugate acrylic, regular polyprepylene and conjugate polypropylene as synthetic waddings. The results of this study are as follow: 1. The warmth retentivity is highest in silk. Following silk in descending order is cotton, conjugate acrylic, polyester, regular acrylic, wool, polyamide, conjugate polypropylene and regular polypropylene. There is not any significant relationship between warmth retentivity and the conductivity of the fibers. 2. Transmission by radiation through the fiber waddings is highest in conjugate polypropylene. Following conjugate polypropylene in descending order is regular polypropylene. polyester. polyamide, conjugate acrylic, regular acrylic, wool, cotton, and silk. This is seen to be in nearly reversed order to the abovementioned order of warmth retentivity. In this respect, warmth retentivity with loose fibreous material as in the case of bedding stuff is primarily affected by the interceptive function of the fibers in heat radiation. 3. Warmth retentivity becomes lower with increasing air content of the waddings. This is because heat transmission by radiation incrases as air content increases. The air content increase is due to the fact that the air is unable to intercept heat radiation. In addition, heat transmission accelates in proportion to the increase in convection as the air gap enlarges.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.67-78
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• 1993

In one bath dyeing system of silk/PET fiber blend fabric with acid/disperse dyes, adsorption behavior of disperse dyes and acid dyes on silk and PET fabrics were examined. In the dyeing of PET with C.I.Disperse Red 19(Red 19) and C.I.Disperse Red 60(Red 60) at 10$0^{\circ}C$(carrier dyeing) and 13$0^{\circ}C$, dye uptake with Red 60 was higher than that with Red 19. When the silk/PET dyed with Red 19 and Red 60 at 10$0^{\circ}C$(carrier dyeing) and 13$0^{\circ}C$, dye uptake on PET was influenced by affinity of the dye to the silk fabric dyed together. When the silk/PET dyed with Blue 80/Red 19 and Blue 80/Red 60 at 10$0^{\circ}C$(carrier dyeing) and 13$0^{\circ}C$ for 60 minutes, color of PET dyed with Red 19 and Red 60 was little influenced by Blue 80 but silk dyed with Blue 80 was influenced. Interrelation of K/S value and Munsell value was scarcely any but showed the change tendency of K/S value.

• Textile Coloration and Finishing
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• v.21 no.1
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• pp.38-45
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• 2009

First of all, the properties imparted to PET fabrics are resistance to and recovery from creasing or wrinkling when wet or dry; high resistance to stretch in the filament yarns but not in the staple; high abrasion resistance; good texture and appearance; resistance to heat ageing; good chemical resistance and good resistance, behind glass, to sunlight. But, the low moisture regain of PET fabric conduces to static troubles in textile processing. Furthermore, garments made from PET may, during wear, develop electric charges which attract to the fabric particles of soil(dirt, swarf, dust) flying in the air, so that the cuffs of shirts, for example, become soiled quickly and are not easily laundered clean. The sericin constitutes 25$\sim$30％ of silk protein and surrounds the fibroin fiber with sticky layer that supports the formation of a cocoon. The useful biochemical properties of sericin protein are oxidation resistant, antibacterial, UV resistant, hydrophilic property, and good affinity with hydrophobic material. These properties can be used as an improving reagent or a coating agent for natural and synthetic fibers, fabrics, and other intermediate products. The sericin is also applied to cross-link, and can be blended with other materials. In this study, we modified the surface of PET fabric by mixture of sericin finishing agent; sericin, polyuretane binder and 1,2,3,4-butanetetracarboxylic acid (BTCA) cross-link agent. Also, we investigated the finshing effect; moisture regain, stiffness, handle, drape and electrostatic. The moisture regain of PET fabric treated with sericin finishing agent was higher than that of untreated PET fabric. As a result of evaluating influence about handle of PET fabrics treated with sericin finishing agent, it was confirmed that the sericin finishing agent could be use as a linen like finishing agent.

• Textile Coloration and Finishing
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• v.29 no.3
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• pp.105-114
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• 2017

High tenacity polyethylene(HTPE) fiber is one of the most important synthetic fibers which possesses outstanding properties such as low density, excellent surface hardness and scratch resistance, superior electrical insulation and low cost. In this study, we dyed high tenacity polyethylene filaments using three different solvent dyes based on log P calculations. We evaluated the dyeing characteristics of dyed high tenacity polyethylene filaments based on dyeing temperature, dyeing time and concentration of solvent dyes. We also analyzed the tensile strength and elongation properties of dyed high tenacity polyethylene filaments with various dyeing temperature and dyeing times. The optimized dyeing condition can be found at $120^{\circ}C$ for dyeing time of 1 hour with 4%(o.w.f.) of solvent dyes.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.6
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• pp.425-434
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• 2019

It is important to ensure the seismic safety of pile-bent bridges constructed in areas with thick soft ground consisting of various soil layers against seismic motion in these layers. In this study, several synthetic seismic waves that are compatible with the seismic design spectrum for rock sites were generated, and the ground acceleration history of each soil layer was obtained based on ground analyses. Using these acceleration histories, each soil layer was modeled using equivalent linear springs, and multi-support excitation analyses were performed using the input motion obtained at each soil layer. Due to the nonlinear behavior of the soft soil layers, the intensity of the input ground motion was not amplified, which resulted in the elastic behavior of the bridge. In addition, inputting the acceleration history obtained from a particular layer simultaneously into all the ground springs reduced the response. Therefore, the seismic performance of this type of bridge might be overestimated if multi-excitation analysis is not performed.

• Analytical Science and Technology
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• v.13 no.1
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• pp.89-95
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• 2000

Three grades of activated carbon fibers (ACFs) were prepared from various precursors of plantic, synthetic, and mixed fabrics of viscose rayon and cotton. The ACFs an exhibited type I isotherms on the adsorption of nitrogen or argon. Micropore analysis revealed that the ACFs have uniform micropore size distribution in which their peak diameters were in the range of $5.6{\pm}0.3{\AA}$. The BET surface area of ACFs up to $1600m^2g^{-1}$ was proportional to the adsorption capacity of iodine. The BET values of the ACFs prepared were proportional to the burn-off degree of the products.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.95-103
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• 2012

In order to improve the dimensional stability and mechanical performance of cement-based composites, the effect of an expansive admixture based on calcium sulphoaluminate (CSA) on the shrinkage and mechanical properties of strain-hardening cement-based composite (SHCC), which exhibits multiple cracks and pseudo strain-hardening behavior in the direct tension, is investigated. Polyethylene fibers reinforced SHCC mixtures with three levels (30, 70, and 100MPa) of compressive strength were compared through free shrinkage, compressive strength, flexural strength, and direct tensile strength measurements. The SHCC mixtures were cast with and without replacing 10% of Portland cement content with CSA admixture. According to test results, CSA admixture is effective in reducing shrinkage of SHCC material. SHCC mixture with CSA admixture exhibited a little higher strength than companion mixture without CSA admixture.