• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.162-168
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• 2014

The friction and wear characteristics of the rubber matrix composites filled with nano sized silica particles were investigated at ambient temperature by pin-on-disc friction test. The volume fraction of silica particles was 19%. The cumulative wear volume and wear rate of these materials on counterpart roughness were determined experimentally. The major failure mechanisms were lapping layers, deformation of matrix, ploughing, debonding of particles, fracture of particles and microcracking by scanning electric microscopy photograph of the tested surface. The cumulative wear volume showed a tendency to increase with increase of sliding distance. The wear rate of these composites tested indicated low value as increasing the sliding distance.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.3
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• pp.27-33
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• 2008

It is shown that the rate of wear can be related to 'index of wear intensity' using a leaf-spring in the disc on disk on wear tests. Since both upper and lower specimens have used the same hardness values, equivalent hardness of 'the index of wear intensity' used the mean hardness value of specimens. This index is derived from the external variables of load, sliding speed and the hardness of the sliding pairs. The wear behavior as the hardness of the sliding elements on the dry wear has been investigated using a disc on disc configuration. The materials of the specimens are used as ten kinds along their hardness. Using experimental data, we figured the relationship between wear rate and index of wear intensity. A newly wear equation had been derived the result using a leaf-spring in disc on disc wear system.

• Journal of the Korean institute of surface engineering
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• v.37 no.3
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• pp.137-145
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• 2004

This study surveys the microscopic wear of CVD TiN coatings in repeated sliding, using the SEM Tribosystem as in-situ system. According to the research, the depth of wear groove and the specific wear amount are changed by the transition of the microscopic wear mode. This investigation leads to the fact that the change of wear characteristics produces the transition of the wear mode. In this survey, four modes are observed for CVD TiN coatings with the thickness of 1.6$\mu\textrm{m}$: ploughing, powder formation, flake formation and coating delimitation. The microscopic wear properties is quantitatively evaluated in terms with the microscopic wear mode and the specific wear amount. These relationships prove that the observation of wear modes with a SEM Tribosystem is useful to evaluate wear properties.

• Journal of the Korean Society of Costume
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• v.64 no.6
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• pp.33-46
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• 2014

The purpose of this study is to present basic data for the standardization of the sizing system for children's wear by investigating the current production and sizing system of Korean children's wear brands. The result of conducting a survey of 20 brands show the following: first, regarding the age bracket of Korean children's wear, it ranged from 3~15 years old. Most of the brands divided up the sizes into 4 or 5 different groups. Second, the utilization of a bodice basic pattern was low during the manufacturing of a pattern, and the basic pattern had been used for the item. Third, the designation of garment sizes were done using height or height-chest measurement or height-waist measurement. Fourth, the brands used the smallest size as the basic size in most cases. Most of the brands had similar deviations for any grading deviations. In conclusion, it appears necessary to restructure the unity of size designation and the sizing system in order to establish the sizing system of children's wear, which features diverse age brackets and various body types.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.100-109
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• 1997

Tappet is the part which consists of valve train system in Over Head Valve type diesel engine. The role of tappet is to open and close the intake/exhaust valve by rotating with cam. There are wear problems like scuffing or pitting in cam/tappet system because of the higher Hertzian contact stress and sliding wear characteristics between cam and tappet. In this paper, to find optimal materials combination in cam/tappet system, wear test and rig test were performed. $Si_3N_4$, chilled cast iron, sintered alloy were selected for tappet materials. As the result of test, it is found that $Si_3N_4$ tappet has the excellent wear properties.

• International Journal of Safety
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• v.5 no.1
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• pp.10-16
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• 2006

A suspended hemispherical silicon asperity moving over a silicon plate was simulated. The simulation results on friction and wear in the interface between the two can help obtain more durable miscroscale structures. Silicon structures were constructed with Tersoff three-body potential. Dependence of friction and wear of the asperity on both the atomic arrangement in the plate and the moving direction was investigated under the condition that the asperity is subject to the attractive normal force due to the plate. The results show that the variation of friction force with the movement of asperity, and the occurrence of adhesive wear are attributed to the formation and rupture of asperity, junction between the asperity and the plate. The friction force and wear are smaller when the asperity is incommensurate with the plate, and they also depend on the moving direction of the asperity over the plate.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.1-10
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• 2016

Magnetic disks have been used for decades in auxiliary storage devices of computer systems. In recent years, the use of NAND flash memory, which is called SSD, is increased as auxiliary storage devices. However, NAND flash memory, unlike traditional magnetic disks, necessarily performs the erase operation before the write operation in order to overwrite data and this leads to degrade the system lifetime and performance of overall NAND flash memory system. Moreover, NAND flash memory has the lower endurance, compared to traditional magnetic disks. To overcome this problem, this paper proposes EPET (Enhanced Prediction and Elapsed Time) wear leveling technique, which is especially efficient to portable devices. EPET wear leveling uses the advantage of PET (Prediction of Elapsed Time) wear leveling and solves long-term system failure time problem. Moreover, EPET wear leveling further improves space efficiency. In our experiments, EPET wear leveling prolonged the first bad time up to 328.9% and prolonged the system lifetime up to 305.9%, compared to other techniques.

• Fashion & Textile Research Journal
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• v.18 no.5
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• pp.647-657
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• 2016

This study investigated domestic and foreign cycle wear sizing systems for the domestic market and provided basic data for development of a high functional cycle wear with excellent fitness qualities. Each brand was found to have different dimension items and different sizes as well as size deviation and range according to each item. Therefore, a size selected by referring to the dimension items would be expected to have confusion when selecting a size. Domestic brands are able to selects sizes relatively easily because they suggest sizes mainly by height and weight (which are a universal size). However, the development of a sizing system for domestic cycle wear brands is needed because each brand have different sizes according to its dimension items. Foreign brands are also different from domestic brands in size marking items and sizes according to items. Therefore, the establishment of a sizing system standard for foreign brands is necessary because there could be a problem with fitness in the same sizes selected for domestic brands. Cycle wear is also able to cover various body types due to the elasticity of its material; however, and evaluation of fitness and a follow-up study will be necessary to develop cycle wear with a fitness that is proper for a Korean body type.

• The Research Journal of the Costume Culture
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• v.8 no.2
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• pp.272-281
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• 2000

The purpose of this study is to provide for the basic data useful to the effective production. For this purpose, 180 Korean mothers who bring up from newborns to four-year-old babies were sampled to survey the problems on size occurred by wearing and purchasing the Infants'Wear and positively identify the factors affecting the fitness. Data is processed by a computer(SAS) and analyzed by using frequency, perentage, mean, χ²-test, Duncan-test. The main results of this study are as follows ; 1. Consumers'awareness of sizing system of Infant's wear tent to present relatively high and tend to purchase their infants'wear larger than actual sizes or that consumers'preferences depend little on size adaptation. 2. As a result of analyzing the part not fit, neck circumference, waist circumference, total length, neck back-waist length is short, sleeve length, pants length, shoulder length is big. In all, it has been found through this study that fitness and awareness of sizing system of Infant's Wear in purchasing infants'wear was influenced by many external factors. Therefore, in order to maximize the size adaptability for infants, Infants'Wear must be present the reasonable sizes and specifications for infants'wear in consideration of domestic and foreign specifications and infants'health condition.

• Journal of Power System Engineering
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• v.12 no.3
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• pp.60-65
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• 2008

This study aims at investigating the wear properties of thermally sprayed $Al/Al_2O_3$ metal matrix composite(MMC) coating against different counterparts. $Al/Al_2O_3$ MMC coatings were fabricated using a flame spray system on an Al 6061 substrate. Dry sliding wear tests were performed using the sliding speeds of 0.2m/s and the applied loads of 1 and 2 N. AISI 52100, $Al_2O_3$, $Si_3N_4\;and\;ZrO_2$ balls(diameter: 8mm) were used as counterpart materials. Wear properties of $Al/Al_2O_3$ MMC coatings were analyzed using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDX). It was revealed that wear properties of $Al/Al_2O_3$ composite coatings were much influenced by counterpart materials. In the case of AISI 52100 used as counterparts, the wear rate of composites coating layer increased according to the increase of the applied load. On the contrary, in the case of ceramics used as counterparts, the wear rate of composites coating layer decreased according to the increase of the applied load.