• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.321-324
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• 2002

Recently, organic-inorganic nanocomposites have attracted great interest from researchers since they frequently exhibit unexpected hybrid properties synergistically derived from two components[1]. The addition of highly dispersed inorganic nano-sized fillers permits improvement of certain properties of polymers as compared with conventional particulate composites; increase of modulus and strength, improved barrier properties, increase in solvent and heat resistance, and good optical properties[2]. (omitted)

• Journal of the korean Society of Automotive Engineers
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• v.7 no.3
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• pp.56-63
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• 1985

The strength of the mounting bolt of a backing plate is investigated with field test to provide the basic data in the safety evaluation of the wheeled vehicle. As a result, during the braking performance test at a vehicle speed of 32km/h, the shearing stress of mounting bolt is 20.5kg/mm$^{2}$ because the translatory mass of the vehicle is increased 21.6 per cent to incorporate the rotating-mass effect of wheels and other permanently engaged rotating parts.

• Proceedings of the Korean Society of Rheology Conference
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• 2002.11a
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• pp.163-166
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• 2002

No Abstract, See Full Text

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.265-270
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• 2002

Dilatancy is a unique characteristics of granular materials showing the tendency to change volume upon shearing. In this study large triaxial tests were peformed for both the well graded rock and the poorly graded rock. And the shear strength of rockfill materials considering dilatancy is evaluated based on the test results. For the rock materials of this study the contribution of dilatancy in the maximum internal friction angle is as much as -6.0%∼3.0% of the internal friction angle measured at peak

• Computers and Concrete
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• v.31 no.5
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• pp.395-403
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• 2023

The paper investigates the effect of two parameters - sand content (SC) and grain migration during shearing - on the mechanical properties of gravel-sand mixtures. Consolidated undrained (CU) triaxial tests were carried out on eight series of mixtures containing gravel (1<d<16 mm) and sand (0.1<d<1 mm). The prepared mixtures have sand contents of 0, 10, 15, 20, 40, 54, 94 and 100%, and a relative density of 60%. The transition sand content (TSC) is experimentally defined and marks the transition from gravel-driven to sand-driven behavior. For SC<TSC, the dry density of the mixture increases with SC. This induces an increase in undrained peak strength and dilative trend. The slope and position of the critical state line (CSL) are also deeply dependent on SC. At SC=TSC, the mixtures exhibit the largest dry density and yield the highest undrained peak strength and the largest dilative trend. During shearing, large internal migration of grains was observed at the TSC, causing heterogeneity in the sample. Analysis of the CSL deduced from the final points of the triaxial tests shows that, at the TSC, failure appears to correspond to the behavior of the coarsest fraction of the soil. This fraction is located in the upper part of the sample, where the sand particles had been eliminated by suffusion. On the other hand, in the more stable materials, the CSL is consistent with the bulk grain size distribution of the soil.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.310-315
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• 2001

The most general feature of contact zone among the mechanical components is elliptical circle. In particular, continuously variable transmission (CVT) of toroidal type has elliptical shape of contact zone under the elastohydrodynamic lubrication condition, where the power is transmitted by the shearing the efluid. Due to the traction of the shear behaviors of lubricant over the small elliptical contact zone, high power of torque is transmitted. During the power transmission, many kinds of mechanical movements occur such as squeezing, sliding, rolling and spinning. The spinning effect that is not common contact behavior in tribological components frequently makes significant abnormal wear damage. In this work, the analysis of elliptical contact of elastohydrodynamic lubrication with spin effect is performed, which will give very useful information to understand the traction behaviors in toroidal type of CVT system.

• Journal of the Korean Society of Clothing and Textiles
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• v.5 no.2
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• pp.49-53
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• 1981

This study was carried out to investigate the drapability of polyester double jersey skirt Drapability is an important aesthetic properties of fabric on clothing construction, In this thesis weight, shearing, bending and non-isotropic characteristics of fabric were regarded as important factors of drapability, Especially for drapability of skirt, I investigated hem effect on various length of hem and skirt, The results were as follows, 1. The less the weight of fabric was, the greater drapability appeared. On fabrics, large pliability and modulus of shear have good drapability, 2. On clothing cutting, non-isotropic property affected on drapability of clothes remark-ably. Drapability order of clothes was greatest in bias direction, next in wale, course direction, 3. The shorter the skirt length and closer at hem line were the larger the hem effect influence upon the drapability of skirt was.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.5
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• pp.607-612
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• 2013

The effect of the flow actuator on the asymmetric vortex structure around the ogive-cylinder body with fineness ratio of 4 flying at the speed of Mach 0.1 at angle of attack of 50 degree is studied. The ogive-cylinder model is developed with the actuator placed near the nose tip and numerically simulated using the in-house CFD code named KFLOW. The numerical simulation employs two different actuator modeling: one is the boundary condition given by blowing normal to the surface and another shearing on the surface. The numerical simulation reveals that response of the vortex structure to the actuation is dependent on the type of modeling as well as the strength and direction of the actuation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.250-256
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• 2017

This study investigated the removal efficiency of organic matter and nitrogen from fish farm effluent by hydraulic retention time (HRT) using an upflow biological filter (ANR system) reactor. The recycling time and influent flow in the reactor were controlled to 14.8, 7.4, 5.5 and 3.2 h to evaluate HRT. In addition, each reactor was coupled to a fixed bed upflow filter charged with media. The results showed that removal efficiency was ${\geq}95%%$ with an HRT of 5.5 h, and nitrification efficiency was reduced to 81% with an HRT of 3.2 h, although nitrification efficiency temporarily decreased due to the shock load as HRT decreased. Total nitrogen removal rate was also reduced to about 65% with an HRT of 3.2 h, which was considered a washout effect of nitrifying and denitrifying microorganisms by increasing the shearing force to the filter media, which decreased organic matter and nitrogen removal efficiency.

• Korea-Australia Rheology Journal
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• v.18 no.3
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• pp.121-126
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• 2006

A carbonyl iron-based magneto-rheological suspension was compressed in the direction of the applied magnetic field and the change in rheological properties was measured. It was found that the compression did not have a large effect on the magneto-rheological response, which is in contrast to recent reports in the literature describing an almost order of magnitude increase in the shear yield stress. The difference can be attributed to the latter test's use of a sliding wedge apparatus which imparts considerable shearing to the sample during the compression.