• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.109-115
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• 2011

Drying characteristics of squids under two dry conditions were investigated using far infrared and heated air. Dry temperatures of 40, 50 and $60^{\circ}C$ with air speed of 0.6, 0.8 and 1.2 m/s were used for evaluating far infrared squid drying. Heated air squid drying at 40 and $50^{\circ}C$ with air speed of 0.8 m/s was used as a control treatment. The two drying were evaluated in terms of drying rate, color, TBA value, aerobic bacteria, cutting shear, penetration strength, and energy consumption. The drying rate of far infrared drying was relatively faster than that of heated air drying. The drying time of far infrared drying was reduced as the drying temperature increased. The color difference of far infrared dried squids was from 18.81 to 22.85, and heated air dried squid had the color different from 23.94 to 24.09. Far infrared dried squid had relatively smaller TBA values that indicate a level of rancidity. The aerobic bacteria of heated air dried squid increased from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g before and after drying, respectively. Far infrared dried squid had relatively smaller increase (from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g). The cutting shear and penetration strength for far infrared dried squids was relatively lower. In addition, far infrared squid drying consumed relatively less energy compared to heated air drying.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.7
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• pp.952-961
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• 2013

This study optimizes a suitable dyeing method for polylactic acid (PLA) fabrics using disperse dyes. For this, disperse red 60 (DR 60), disperse blue 56 (DB 56), and disperse yellow 54 (DY 54) were used and dyed on PLA fabrics dependent of dyeing temperature and time. The fastness of PLA fabrics dyed with three disperse dyes were evaluated; in addition, dye exhaustion, color strength (K/S value), and colorimetric properties of PLA fabrics were compared with PET fabrics. The experiments indicated optimum dyeability of PLA fabrics with disperse dyes. The dyeing temperature was $90^{\circ}C$ for every dye and the dyeing time were 20 min, 60 min, and 40 min for DR 60, DB 56, DY 54, respectively. PLA fabrics had good color fastness to washing, dry cleaning fastness, hot pressing fastness, rub fastness, and perspiration fastness by DR 60, DB 56, and DY 54. The dye exhaustion of PLA fabrics were lower than PET fabrics; however, K/S values were higher than PET fabrics.

• Transactions of Materials Processing
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• v.27 no.4
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• pp.211-221
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• 2018

To estimate the recycling feasibility of high melt-indexed polycarbonate, 3.5 inch LGP, tensile, flexural and impact specimens were injection-molded and the LGP was shredded into scraps. The scraps were injection-molded again and this process was repeated for 4 times. Properties of the sample, i.e., optical properties, mechanical properties and number average molecular weight were measured at each cycle. Based on the results, as the number of reprocessing increased, transmittance decreased at low wavelength and color coordinate was changed systematically to yellow. Yellow index increased more than twofold during 4 recycling processes. On the other hand, the number average molecular weight decreased during recycling processes. Flexural and impact strength showed no tendency according to the number of recycling, but tensile strength decreased sharply after the third recycling process. Based on these properties, it was concluded that the number of recycling for high melt-indexed polycarbonate allowed in this study was one.

• Korean Journal of Child Studies
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• v.35 no.5
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• pp.63-82
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• 2014

The purpose of this study is to elucidate how two young children understand force in rough-and-tumble play. For this purpose, a form of microanalysis(Forman, 2006) was used. They regarded black as the strongest color due to their daily experiences. They assumed that a structure made of black Lego-color-bricks would be strongest and made an experiment of beating it against blocks of other colors. Such repetitive behavior ultimately led them to realize that color had no correlation with strength. They also understood mechanical energy by which a boy's pushing power moves against an object. They tried to strike a bigger or protruding structure and understood that parts might be broken more easily by striking. This experience enabled the boys to realize the principle of resistance. That is to say, in the process of rough-and-tumble play, their misconceptions were gradually removed and they obtained scientific knowledge, including understanding of mechanical energy and the principle of resistance. This study found that two young children constructed knowledge together through the process of tool making and in contending for victory in rough-and-tumble play.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.11
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• pp.1565-1573
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• 2007

This research was aimed to investigate the effect of $K_2CO_3$ instead of NaOH on retting of the kenaf bast. We examined the relationship between separation of fiber bundle and tensile strength besides observing the color, handle and cross sectional view for the kenaf fiber retted with various concentration(100, 150, 200, 250, 500, 1000mmol) of $K_2CO_3$ and double retted with 0.5% pectinase after $K_2CO_3$ retting. The one retted on low $K_2CO_3$ concentration, $150{\sim}200mmol$, showed the best result on color, handle and luster. The separation of fiber bundle started even at the low $K_2CO_3$ concentration, 100mmol, and as the $K_2CO_3$ concentration was higher, the size of the fiber bundle was smaller. In the case of 1000mmol, the fiber bundle became irregular, but they were breaking up into certain way. Regardless of $K_2CO_3$ concentration, the thinner the diameters of the kenaf fiber bundle, the stronger tensile strength have appeared. This result corresponds with the result of cross sectional view. Retting on $150{\sim}200mmol\;K_2CO_3$ concentration was most effective on fiber bundle#s separation and tensile strength. The one with double retted with 0.5% pectinase after $K_2CO_3$ retting showed very small size of fiber bundle and low tensile strength compare to the one just retted on $K_2CO_3$. This decrease of tensile strength seem to be related to damage of the fiber resulted by excessive fibrillation.

• Korean Journal of Human Ecology
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• v.16 no.5
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• pp.1051-1059
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• 2007

This study intends to find out possible variations in physical properties and color of hair depending on dye type(acidic and alkalic) and permanent treatment/hair dyeing procedure. To meet the goals, healthy hair samples were taken from 5 women's hair speciment in 20's without experiencing in any harmful substance via long-term medications. and beauty care using chemicals. To get possible findings depending upon hair dye type and treatment procedure, both acidic and alkalic hair dye were applied on some specimens after permanent treatment, while on other specimens before permanent treatment. In order to determine scale damage, this study used SEM(Hitachi S-2500C) both hair thickness and tensile strength were measured with optical microscope(Nikon, MM-60/L3T) and Instron (4482-standard). Wave configuration was measured transverse and longitudinal round diameter. The chromaticity of each specimen was measured using a spectrocolorimeter(Color Techno System, JP/JX-777) with visual $C/2^{\circ}$ (at $2^{\circ}$ with C light source) monitor fixed to determine Lab and CMYK values. As a result, it was found that hair specimens were more significantly damaged with alkalic hair dye treatment than with acidic hair dye treatment, while hair specimens were more effectively dyed with the former hair dye type than with the latter one. For possible results depending on treatment procedure, it was found that hair specimens were less damaged but more effectively dyed with permanent treatment followed by hair dyeing than vice versa. Therefore, it was concluded that permanent treatment followed by acidic hair dyeing would be more effective in reducing hair damages.

• Textile Coloration and Finishing
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• v.17 no.3 s.82
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• pp.8-15
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• 2005

Cationic dyeable polyester(CDP) fabric was annealed at varying temperatures range from $120^{\circ}C$ to $220^{\circ}C$ for 1, 3, and 5 min under tension. Dyeing rates of CDP fabrics were measured with cationic and disperse dyes at $100^{\circ}C$ and $120^{\circ}C$ in water system. Also X-ray diffraction pattern, DSC thermograms and dyeability of fabric with cationic and disperse dyes were investigated. The intensities of X-ray diffraction peaks of annealed fabric were increased with increasing in annealed temperature, and peak became sharp with heat setting temperature. The apparent color depth (K/S) of CDP fabric initially decreased with increase of heat-setting temperature up to $160\~180^{\circ}C$ and then increased at higher temperature. The shearing modulus(G) and surface roughness were increased with annealing temperature.

• Journal of the Korean Home Economics Association
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• v.46 no.7
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• pp.1-6
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• 2008

The purpose of this study was to investigate the changes in properties of silk fabrics dyed with safflower red and yellow colorants under Ultraviolet(UV)-light. Silk fabrics dyed with safflower red and yellow colorants were compared with each other after uv-light exposure in terms of K/S value, color changes(${\Delta}E$), morphology, and strength retention. The K/S value rapidly decreased with increasing exposure time for samples of both colorants, but the extent of decrease was less for the samples dyed with safflower yellow colorant, than that of the samples dyed with safflower red colorant. Regarding the color changes with increasing exposure time, $L^*$ and $b^*$ increased, $a^*$ decreased, and thereby ${\Delta}E$ increased in the red-dyed samples, whereas $L^*$ increased, $a^*$ and $b^*$ decreased, and so ${\Delta}E$ increased in the yellow-dyed samples, indicating that the UV-light induced fading and changes of hue, value and chroma value. However, the color change of the yellow-dyed samples was less than that of the red-dyed samples. SEM images showed a severe degradation by UV-exposure for both colorant samples. Tensile strength slowly decreased until 14 days, but rapidly decreased thereafter. Strength retention of the yellow-dyed samples was higher than that of red-dyed samples.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.34-36
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• 2008

The several monoazo red dyes having different alkyl substituents were synthesized to dye unmodified polypropylene fiber. The affinity of the dyes onto unmodified polypropylene was increased with the increase of the length of alkyl substituents. Therefore, the hexyl-substituted dye having the longest alkyl group in this experiment showed very high color strength of dyeings with K/S value of over 28 at maximum adsorption wavelength. The color fastnesses of washing, light, rubbing and sublimation were also improved significantly for the longer alkyl substituted dyes.

• Textile Coloration and Finishing
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• v.15 no.3
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• pp.168-175
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• 2003

Ultramicrofiber(UMF) PET knitted fabric and regular PET plain woven fabric as reference sample were impregnated with waterborne polyurethane(PU) in a two-step process with dyeing/PU treatment and PU treatment/dyeing to investigate the effect of the treatment sequence. The waterborne PU impregnated fabrics were dyed with two kinds of vat and disperse dyes to investigate the dyeing properties and the dyeing fastnesses. In vat dyeing the rank of color strength(K/S) was in order of dyeing/PU impregnation > dyeing only > PU impregnation/dyeing, whereas in case of disperse dyeing, the order was dyeing/PU impregnation > PU impregnation/dyeing >dyeing only. Wash fastness of vat dyeing showed a higher 2-3 grade than disperse dyeing, while rubbing and light fastnesses were not good for disperse dyes.