• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.112-119
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• 2010

Recently, as the matters of environmental pollution, the energy exhaustion and alternative energy source have become more important issues, around industrial countries and the effort to improve fuel consumption is progressed continuously for decrease of air pollution. In an effort to improve fuel consumption for passenger cars, the study of DLC (Diamond Like Carbon) coating which is widely known to good wear characteristics come to the forefront. Therefore, in present study, it was investigated to the influence of DLC coating layer for wear characteristics with the piston ring material and then suggested to the development process for advanced automotive engine parts that showed improved wear characteristics. From these results, Finally, it will be contributed to improve the fuel consumption for passenger vehicles.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.651-655
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• 2003

The rolling-stocks used in conventional line have suffered wheel problems due to lack of adaptability with track. These brought out severe wheel flange wear, these have caused unstable ride characteristics of rolling-stock. Especially, Wheel flange wear is severely influenced by wheel profile but lateral suspension characteristics. This study was started to induce wheel profile suitable for domestic railway environment. Thus, we analyzed the wear characteristics of wheel profiles that are being applied to railway rolling-stock in KNR. To analyze wheel wear characteristics, we have conducted experiment studies for passenger rolling-stock and obtained useful datum.

• Tribology and Lubricants
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• v.16 no.3
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• pp.173-181
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• 2000

Friction, wear and corrosion characteristics of various MoS$_2$ bonded film lubricants were investigated to apply them to automotive wheel joints. MoS$_2$ bonded film lubricants were formulated by combinations of several additives and binders, and they were coated onto the pre-treated surfaces of specimens. Friction and wear characteristics were evaluated with Falex pin & vee-block test and LFW-1 block-on-ring test. For the corrosion resistant characteristics of the films, salt solution spray corrosion tests were performed. Results showed that MoS$_2$ bonded films containing both inorganic and organic corrosion-resistant additives yielded a synergy effect on anti-corrosion resistance. Also, binders having the better water-proof and thermal stability showed the lower friction and higher corrosion resistance.

• Tribology and Lubricants
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• v.36 no.6
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• pp.342-349
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• 2020

The rapidly increasing threats to the environmental has increased the demand for biodegradable lubricants. Vegetable oils, such as olive, coconut, and sunflower oils, are readily obtainable and are not harmful, unlike synthetic and mineral oils. The tribological characteristics of these oils should be adequately examined for industrial applications. In this study, the lubrication characteristics of olive oil is investigated using a pin-on-disk-type tribometer under 500 gf of normal force, and the examination results are compared and analyzed with those of commercial synthetic lubricants for friction and wear. In addition, stearic acid, which is a type of saturated fatty acid, is mixed with olive oil as an additive to improve its lubrication characteristics. Olive oil with stearic acid additive is thus observed to exhibit the lowest friction coefficient for rotational speeds of 200 to 800 rpm. According to the wear analysis, a minimal amount of wear is observed when no additive is used. Hence, olive oil is able to effectively reduce friction and wear at relatively low speeds. These low friction and wear characteristics of olive oil are attributed to its compatibility with the substrate.

• Journal of Fashion Business
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• v.15 no.1
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• pp.92-102
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• 2011

The purpose of this research is to study the types of name spectrum and their characteristics of domestic men's wear brands focusing on formal and casual wear and also examine the differences based on the type of brands' product and brand style. Total 184 of men's wear brands, which were consisted of 66 formal wear brands and 84 casual wear brands, were selected from '2009 Korea Fashion Yearbook'. For data analysis, quantitatively evaluated the frequency and qualitatively evaluated the image of brand product and the meaning of brand name. The result as follows; 1. The domestic fashion brands for men's wear appeared to have four types of name spectrum. The descriptive name was the most frequently showed, and followed by arbitrary, suggestive, and coined name. For formal wear brands, four types of name spectrum were appeared in the order of descriptive, suggestive, coined, and arbitrary name. In casual wear brands, three types of name spectrum were appeared in the order of descriptive, arbitrary, and suggestive name. 2. The characteristics of men's brand name according to their name spectrum was as follows.; In the descriptive brand names, person's name was used the most and some ascribed the characteristics, feature or geographic location of the product. The suggestive brand names contained images and symbols of the product and also implied the relevant benefit information in a particular product context. In the arbitrary brand name, they imply the various meanings according to the product and are made up of either coined or natural. For the coined name, some bear the ideology or symbolized the characteristics of product itself. 3. The descriptive name spectrum showed the most in domestic menswear brands, regardless of the brand type. Except this, there were differences in the type and the frequency of name spectrum depending on the brand type.

• Journal of Fashion Business
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• v.13 no.5
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• pp.1-12
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• 2009

This study looked into the characteristics of participants in dance sports, which is being positioned to be one of everyday athletic activities among people, and investigated the actual purchasing of dance sports wear with the subjects of its participants as a preceding study for the development of dance sports wear to consider their characteristics. The questionnaire method was used, and descriptive and crosstabulation analysis was conducted with a spss 12.0. The findings are as follows. 1. As the results that examine general characteristics of dance sports participants, the number of those in their 20's was the largest, while the number of women was larger than that of men. Regarding the practicing period, those of one year or longer up to 4 years occupied the largest proportion, and the rate of Latin American dance participants was larger than that of modern dance ones. 2. As to the actual purchasing of dance sports wear, the purchase motivations were found to be in the 'contest participation' for teenagers and those in their 20's, while those in their 40's or over purchased their wear for the purposes of 'following the fashion' or 'club gatherings.' As for the sources of information at the time of purchase, teenagers relied on internet and those of 20's or over got the information through the persons nearby. As their ages got higher, the ready-made sports wear was preferred, while as their practicing periods got longer modern dance participants purchased the sports wear of higher prices. Participants in their 30's and those practicing 7 years or longer possessed a comparatively larger number of dance sports wear and they considered importantly of designs and fit at the time of purchase. Therefore, the development of dance sports wear designs should be made to accord with the participants' age groups so that they might be sensitive to the fashion and clearly represent their personality for the junior group and durable enough to last long for the senior group.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.772-778
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• 2007

For the wear characteristics assessment of Saemaul train passing through curves, an analysis model for multi-car system has been developed. By using this model and ADAMS/Rail, sensitivity analyses have been conducted for the wear characteristics by changing the related parameters. At low speed, the wear number and the sliding mean of right wheel showed higher than left wheel, while those of left wheel showed higher than right wheel at high speed. According to the decrease of curve radius, the wear number and the sliding mean were increased. When the length of transition curve was increased, the wear number and the sliding mean was increased. And according to increase of cant, the wear number and the sliding mean were increased.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.2
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• pp.182-188
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• 1994

This expermintal study is intended to investigate he development of flank wear in turning os SUS304 which is used in industrial applications and is acknowledged as a machining difficult material. In cutting process, change of velocity, change of feed, and change of depth of cut were investigated about the effect of flank wear, and slenderness ratio is also investigated. The variations of unit cutting force with the change of rake angle and the change of uncut chip area are observed. The friction angles are calculated for the change friction force and observed. The friction angles are calculated for the change friction force and normal forcd on the different rake angles. From this experimental study, the following results can be said. 1. Under the high cutting speed condition, the flaank wear is affected by the feed and depth of cut, but the influence of feed and depth of cut to the flank wear is reduced when the velocity is low. 2. The smaller slenderness ratio is, the shorter the tool life results in high cutting speed, and the lower cutting speed is, the lower the effect of slenderness ratio to the flank wear is. 3. Using the characteristics of force-RMS, the flank wear of a tool can be detected. There are almost no differences between the RMS characteristics of cutting force and feed force.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.401-402
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• 2002

Diesel engines have many sliding parts with solid body contact. For example, a piston-ring and a cylinder bore, a valve and a valve-seat, a cam and a valve tappet. These parts have a severe wear problem. during engine life times. During these times, the valve tappet has abnormal wear such as scuffing and pitting due to a high hertzian contact stress between the cam and the tappet. Excessive wear problems frequently occur to both the cam and the tappet. To solve these problems, we developed an advanced wear resistant tappet. The developed tappet consisted of a hard-metal wear part and a steel body. To increase a bonding strength, those two parts, were directly bonded to each other. Also to decrease a bonding temperature, we developed the composition of Ni-binder materials in the hard metal. To estimate the wear characteristics of the newly developed tappet, we performed wear tests and engine dynamo tests in order to compare them with a conventional Fe-base tappet. As a result, the newly developed tappet has better wear characteristics than those of the conventional tappet. In addition, we performed a 100,000km field-test, and the newly developed tappet showed much improved wear resistance.

• 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.