• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2003년도 춘계학술대회 논문집
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• pp.8-13
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• 2003

Frictional sound of 13 vapor permeable water repellent fabric by sound generator were recorded and analysed through FFT analysis. The frictional Sounds were quantified by calculating total sound pressure(LPT), the level range ΔL and the frequency difference Δf. Mechanical properties were measured by KES-FB. LPT values of specimens finished wet coating were higher than those of dry coating. Values for bending rigidity, shear stiffness, surface roughness and compressional recovery of polyurethane fabrics increased compared with the cire finished fabrics. Laminated fabrics had high values of frictional coefficient and low values of surface roughness. LPT showed significant correlation with compressional energy, weight and thickness. (ΔL) was highly correlated with compressional linearity, frictional coefficient, compressional recovery, and (Δf) with tensile linearity, compressional energy, thickness, and weight.

• 한국의류학회지
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• 제20권4호
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• pp.647-654
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• 1996

The purpose of this study was to analyze the effect of fiber type, compressional resilience and moisture transport properties of wool and polyester fiber on the heat transfer of insulation nonwovens. The results obtained were as follows: 1) Overall heat transfer of wool nonwoven was slightly higher than that of polyester nonwovens. Warmability of wool nonwoven was lower than that of polyester nonwovens. The radiative heat transfer was in the range of 11~18% of overall heat transfer in polyester nonwovens and 25% in wool nonwoven. 2) As wool nonwoven compressed, overall heat transfer was increased by increasing radiative heat transfer and wamability was decreased due to the poor compressional resilience. 3) Increasing rate of heat transfer by moisture absorption in wool nonwoven was lower than that of polyester nonwovens. Thickness and compressional resilience of wool nonwoven were reduced extremely by moisture absorption.

• The Journal of the Acoustical Society of Korea
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• 제25권2E호
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• pp.49-55
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• 2006

Compressional wave velocity (Vp), shear wave velocity (Vs), elastic and physical properties, and electrical resistivity for two core sediments obtained from Southeastern Yellow Sea Mud (SEYSM) were measured and computed. The sediments consist of homogeneous mud (mostly silt and clay) with shells and shell fragments. As a result, the mean grain size is uniform ($7.5-8.5{\Phi}$ throughout the core sediments. However, physical properties such as wet bulk density and porosity show slightly increasing and decreasing patterns with depth, compared to the mean grain size. The compressional (about 1475 m/s in average) and shear wave (about 60 m/s in average) velocities with depth accurately reflect the pattern of wet bulk density and porosity. Electrical resistivity is more closely correlated with compressional wave velocity than physical properties. The computed Vp/Vs and Poisson's ratios are relatively higher (more than 10) and lower (approximately 0.002) than Hamilton's (1979) data, respectively, suggesting the typical characteristics of soft and fully water-saturated marine sediments. Thus, the Vp/Vs ratio in soft and unconsolidated sediments is not likely sufficient to examine lithology and sediment properties. Relationships between the elastic constant and physical properties are correlated well. The elastic constants (Poisson's ratio, bulk modulus, shear modulus) given in this paper can be used to characterize soft marine sediments saturated with seawater.

• 한국의류산업학회지
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• 제1권4호
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• pp.358-362
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• 1999

두께와 무게가 다양한 23종의 직물을 대상으로 최대하중 10, 20, 35, 50, 70 $gf/cm^2$의 5종류 다양한 조건 하에서 압축-두께곡선을 측정함으로써 저응력에서 압축특성과 두께, 태를 분석하였다. 최대하중이 증가함에 따라 LC(curve linearity)는 증가하였으며 WC(compressional energy)는 감소하였다. 또한, 최대하중에 따라 RC(compressional resilience)는 변화가 없었다. LC와 WC는 직물이 두꺼울수록 크게 나타났으며 RC는 중간 두께의 직물에서 가장 크게 나타났다. 최대하중 20 $gf/cm^2$에서 측정한 LC와 WC가 주관적 태 평가결과와 가장 상관이 깊었으며 Speamnan's rho는 .86과 .82였다.

• 한국의류학회지
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• 제11권2호
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• pp.13-21
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• 1987

Nowadays, the amount used carpets are on the increase, according to the improvement of life-style. The pleasantness of carpet is caused by the properties of pile, because the most carpets are made pile fabric. For that reason, a study on the compressional properties of carpet is very important issue. This study has been carried out to investigate the differences of compressional properties in various acrylic carpets which were Cut, Tufted, Jacquard and Shag. Each acrylic carpets was transformed to 4, 6, 8 mm of pile height, as results of transformation, we could get the pressure-thickness curve and pressure-deformation curve. The results are summarized as follows. 1. Rate of compression increases, compressive resistance and compressive elasticity decr-eases, as pile height increases. 2. Regardless of pile height, compressive elasticity reached the limit in recovery period at about 10 minutes. 3. Work of compression increases, as pile height increases. 4. Work of compression decreases, as apparent density increases. 5, Cut-type carpet has the best cushion.

• Fibers and Polymers
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• 제4권4호
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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.

• Geomechanics and Engineering
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• 제37권3호
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• pp.253-262
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• 2024

Dynamic properties are pivotal in soil analysis, yet their experimental determination is hampered by complex methodologies and the need for costly equipment. This study aims to predict dynamic soil properties using static properties that are relatively easier to obtain, employing machine learning techniques. The static properties considered include soil cohesion, friction angle, water content, specific gravity, and compressional strength. In contrast, the dynamic properties of interest are the velocities of compressional and shear waves. Data for this study are sourced from 26 boreholes, as detailed in a geotechnical investigation report database, comprising a total of 130 data points. An importance analysis, grounded in the random forest algorithm, is conducted to evaluate the significance of each dynamic property. This analysis informs the prediction of dynamic properties, prioritizing those static properties identified as most influential. The efficacy of these predictions is quantified using the coefficient of determination, which indicated exceptionally high reliability, with values reaching 0.99 in both training and testing phases when all input properties are considered. The conventional method is used for predicting dynamic properties through Standard Penetration Test (SPT) and compared the outcomes with this technique. The error ratio has decreased by approximately 0.95, thereby validating its reliability. This research marks a significant advancement in the indirect estimation of the relationship between static and dynamic soil properties through the application of machine learning techniques.

• 한국염색가공학회지
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• 제10권6호
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• pp.10-19
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• 1998

This study surveys the mechanical properties such as tensile and compressional properties to the weight reduction rate of PET fabrics with various weft linear densities, weft t.p.m. and desities. 18 kinds of plain and 12 kinds of satin weave fabrics were woven and processed with variation of weight reduction rate(0％, 12％, 25％ and 30％) in dyeing and finishing processes. Tensile work, resilience and compressional work and resilience of these finished fabrics treated with different weight reduction rates were measured by KES-FB System and discussed with various wok linear densities, weft t.p.m., densities, and weight reduction rates.

• 한국의류학회지
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• 제24권3호
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• pp.440-447
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• 2000

The effects of DP finishing conditions including process technique and finishing agent on the mechanical properties and hand of cotton fabrics were investigated. 100% cotton fabrics were treated with NMA/DMDHEU and NMA/YF using wet-fixation and steam-fixation process. For comparison, conventional pad-dry-cure process was used with DMDHEU. After DP finishing, tensile and compressional resilience increased and bending hysteresis decreased, resulting in the improvement of dimensional stability of cotton fabric. WF and SF process rendered fabrics better shear properties, tensile energy, and compressional linearity and energy than PDC process. However, SF process produced fabrics with higher geometrical roughness than WF process. After DP finishing, primary hand values except Koshi increased, resulting in the increase of total hand value of cotton fabric.

• 한국염색가공학회지
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• 제9권4호
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• pp.28-38
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• 1997

Peach skin fabrics were washed by the general and ultrasonic washing systems using different conditions. The physical properties of the washed fabrics were estimated. The following results were obtained through experimental data and their analysis. The tensile properties were changed due to fabric running speed and washing methods. The lower the running speed, the higher the extensibility and resilience and the lower the linearity and tensile energy. In the general washing method, the extensibility and resilience had lower values than those of the ultrasonic washing method and the linearity and tensile energy had the higher values than those of the ultrasonic washing system. The bending properties, bending moment and histeresis, were estimated. These values were generally lower in the ultrasonic washing system than those of the general washing system. The faster the washing speed, the higher the value of hysterisis. The shear properties were affected by the fabric running speed and washing methods. Shear stiffness and hysteresis of shear forces increased according to the increase of the fabric running speed. The values were higher in the general washing system than those of the ultrasonic washing system. The compressional energy was affected by the fabric running speed. The higher the fabric speed the higher the compressional energy. The ultrasonic washing system had lower compressional energy than the general washing system. The higher the running speed, the lower the coefficient of friction and geometrical roughness. The values of geometrical roughness were infienced by the removal of the sizing agent. The higher the remaining sizing agent, the higher the fabric weight and the thicker the thickness of fabric.