• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.609-617
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• 2016

The purpose of this study is to investigate the wear index of toothbrush and related factors in the university students. A self-reported questionnaire was completed by 573 university students from March 16 to April 10, 2015. The questionnaire consisted of general characteristics of the subjects, wear index, and wear rate of the toothbrush. The wear index of 46.9 percent was above 0.400, and the average wear index was $0.403{\pm}0.20$. Overall, the wear index of the toothbrushes was high. 2. As a result of measuring the wear rate of the toothbrushes, the wear rate of 70.4 percent stood at 1 and 2. The average wear rate stood at $1.620{\pm}0.74$. Overall, the wear rate of the toothbrushes was high. 3. As for wear index and wear rate by gender, the wear index and wear rate of the toothbrushes used by the male students were larger than those of the toothbrushes used by the female students. The wear index and wear rate were significantly higher when the toothbrush replacement period was longer. Given the findings of the study, efficient oral health education on the right toothbrush management should be provided for college students to manage their toothbrushes properly.

• 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 Society of Industry Convergence
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• v.7 no.4
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• pp.369-376
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• 2004

It is shown that the rate of wear can be related to on 'index of wear intensity'. Since both upper and lower specimens have used the same hardness values, equivalent hardness of '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 wea rate and index of wear intensity. The result had been derived a newly wear equation in disc on disc wear system.

• Journal of the Korea Society of Computer and Information
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• v.20 no.12
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• pp.1-8
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• 2015

Wear leveling techniques have been studied to prolong the lifetime of NAND flash memory. Most of studies have used Program/Erase(P/E) cycles as wear index for wear leveling. Unfortunately, P/E cycles could not predict the real lifetime of NAND flash blocks. Therefore, these algorithms have the limited performance from prolonging the lifetime when applied to the SSD. In order to apply the real lifetime, wear leveling algorithms, which use raw Bit Error Rate(rBER) as wear index, have been studied in recent years. In this paper, we propose CrEWL(Cold data identification using raw Bit error rate in Wear Leveling), which uses rBER as wear index to apply to the real lifetime. The proposed wear leveling reduces an overhead of garbage collections by using HBSQ(Hot Block Sequence Queue) which identifies hot data. In order to reduce overhead of wear leveling, CrEWL does not perform wear leveling until rBER of the some blocks reaches a threshold value. We evaluate CrEWL in comparison with the previous studies under the traces having the different Hot/Cold rate, and the experimental results show that our wear leveling technique can reduce the overhead up to 41% and prolong the lifetime up to 72% compared with previous wear leveling techniques.

• Tribology and Lubricants
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• v.15 no.3
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• pp.265-271
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• 1999

Wherever there are rotating equipment and contact between surface, there is wear and the generation of wear particles. The particles contained in the lubricating oil carry detailed and important information about the condition monitoring of the machine. This information may be deduced from particle shape, composition, size distribution, and concentration. Therefore, This paper was undertaken to Ferrography system of wear debris generated from lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of Pin and V-Block type by Ti(C, N) coated. It was shown from the test results that wear particle concentration (WPC) and wear severity Index( $I_{S}$), size distribution in normal and abnormal wear have come out all the higher value by increases sliding friction time. Wear shape is observed on the Ferrogram it was discovered a thin leaf wear debris as well as ball and plate type wear particles. This kind of large wear shape have an important effect not only metals damage, but also seizure phenomenon.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2420-2427
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• 2000

In contacting between surface, there is wear and the generation of wear particles. The particles contained in the lubricating oil carry detailed and important information about the condition monitoring of the machine. Therefore, This paper was undertaken for Ferrography system of wear debris generated from lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of Pin and V-Block type by Ti(C,N) coated. It was shown from the test results that wear particle concentration(WPC) ; wear severity Index(IS) and size\distribution have come out all the higher value by increases sliding friction time. By the Ferrogram a thin leaf wear debris as well as ball and plate type wear particles was observed.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.11
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• pp.1389-1398
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• 2005

The purposes of this study are to verify the sales promotion effect of bargain sale of department store, and to investigate the relationship between the effect of bargain sale and the consumer attitude toward economics. For those purposes, secondary data was collected. The data was composed of monthly sales data of women's casual wear, men's suit, inner wear, infant's wear, and golf wear in a department store from 1996 to 2003. The data on consumer attitude toward economics was collected from 'Consumer Attitude Index' issued by SERI. The results are as follows. First, there were differences in the sales promotion effects of bargain sale by merchandise class and by year. Men's suit was the class that the effect was highest, and inner wear was the class the effect was lowest. In addition, the effects were simultaneously lowered by year. Second, sales promotion effect of bargain sale had relationship with consumer attitude index. The yearly transitions of the two data were almost similar. This means that as the consumer attitude becomes pessimistic, the motivation to consume also becomes lower, so that sales promotion effect of bargain sale also decreases. In addition, women's wear and men's suit showed the most similar transition patterns with the consumer attitude index.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.3
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• pp.113-122
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• 2019

Tooth wear is gradually increasing with increasing life expectancy. In particular, it is important to establish a treatment plan in the early stages so that it does not proceed to moderate or severe wear stages. It is essential to diagnose tooth wear accurately in order to plan a treatment for it. There are many risk factors including age, diet, and drugs which affects tooth wear. For the diagnosis of a tooth wear, appropriate index and evaluation method should be used. There were various tooth wear indices such as TWI, Lussi index, BEWE, and TWES. The evaluation method includes clinical examination, dental cast examination and clinical photographs. Recently, a 3D scanner is being used to assess tooth wear. The risk factors, tooth wear evaluation system, the methods of measuring tooth wear, and related literature were reviewed. The strengths and weaknesses of each index and evaluation methods were compared to derive a proper way to diagnose tooth wear.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.151-157
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• 2013

The purpose of this study was to examine the toothbrush bristles' wear index and wear rate used by preschool children to provide information on the establishment of criteria for toothbrush replacement cycle for preschool children. One thousand twenty-two toothbrushes were collected from September 20 to November 16, 2012 was analyzed. The findings of the study were as follows: 1. As a result of analyzing the toothbrush wear index, 48.5% of the collected toothbrushes was above 0.400, and the average wear index was $0.421{\pm}0.239$. 2. As a result of analyzing the wear rate of the toothbrushes, score 2 and 3 accounted for 70.4%, and the average wear rate stood at $1.936{\pm}0.848$. 3. As a result of analyzing the state of toothbrush management, the most common average toothbrush replacement cycle was one or two months (63.9%). Concerning the method of toothbrush replacement, the largest group (52.7%) replied they changed toothbrushes based on the abrasivity of toothbrush bristles, and 16.7 percent did that at the request of parents. Given the above-mentioned findings of the study, preschool teachers and parents should be educated to ensure the successful management of preschool children toothbrushes. In addition, it's required to set evident criteria for the right toothbrush replacement cycle for preschool children, and how to provide oral health education in an efficient way should be considered as well.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.547-555
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• 2016

The wheel wear of a railway vehicle is mainly generated when maneuvering on a curved track. The change in the wheel profile affects the dynamic stability of the vehicle. In this analysis, the wheel wear volume was calculated while changing the velocity and radius of the curve to analyze the wear characteristics of a wheel at a curved section. The wear index was calculated from a vehicle dynamic analysis based on a multibody dynamics analysis and wear volume from a wear model by British Rail Research. The wear volume at a radius of 300 m is dominant compared with other radii. The wear volume was calculated by assigning different coefficients of friction to the tread and flange of the wheel to investigate the effect of lubrication on the wear characteristics. The effect of the improvement by lubrication is calculated by varying the radius of the track, and is assessed on an actual urban railway section.