• 복식
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• 제52권2호
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• pp.71-80
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• 2002

The purpose of this study was to examine the correlation between the shape of the foot and foot abrasion. and to provide preliminary data for shoe manufacturing by comparing the length of a woman's feet and the shoe size. The Martin calibrator and measuring tapes were utilized to measure the shapes of 163 female college students' feet. Indirect measurements were also obtained by line drawing of the feet for additional analysis. Brief questionnaires about what type of shoes are worn were given to the subjects of the study. Data analysis was presented by frequency, percentage, and standard deviations. Factor analysis and correlation co-efficiency of data was conducted on the significance level of p〈.05. The results of the study are as follows (1) The average number of days per week in which the subjects wear ladies' shoes per week were 4.5. Little over half of the subjects (53.87% ) answered that they wear heeled shoes for more than 8 hours per day. The most preferred height of a ladies'shoe heel was between 2 cm and 4 cm, as replied by 41.0% of the subjects. (2) The foot area where abrasion occurs most often was around the heel (51.2%) and the middle part of the sole (50.9%) (3) Factors correlated to the heel abrasion included the circumference and the breadth of the foot. The abrasion on the side of the first toe of mid-sized feet was most affected by the angle of the first the and inner foot line. The height of the foot heel was a significant factor for the abrasion near the anklebone. In conclusion, the abrasion resulted from the inappropriate fitting of the shoe and the foot. Also, the circumference and the width factors were more influential rather than the foot length. Therefore, more database on this should be systemized and available to the footwear manufacturers and the customers for more practical use of shoe size and public education.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.545-546
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• 2012

• Corrosion Science and Technology
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• 제7권6호
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• pp.362-369
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• 2008

The impact abrasion behavior of high manganese steel is investigated under three kinds of impact energy in acid hematite ore slurry by using a modified MLD-10 impact abrasion tester. Through the SEM observation of the worn surface and the optical metallographic analysis of the cross-sectional samples, the corrosive impact abrasion mechanisms of the steel under different impact energies are studied. In acid-hematite slurry, the variations of impact energies would result in synchronous transformation of the impact abrasion properties and mechanisms of the high manganese steel in the corrosive condition, as led different corrosive impact abrasion mechanism under different impact energies.

• 한국터널지하공간학회 논문집
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• 제20권6호
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• pp.1091-1104
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• 2018

암반용 TBM 공사에서 디스크 커터의 마모 예측은 설계 및 시공 단계에서 비용과 공기 측면에서 매우 중요한 요소이다. 디스크 커터 마모 예측에 널리 사용되고 있는 방법으로는 노르웨이 NTNU 모델, CSM 모델과 Gehring 모델이 있지만, 시험의 정확도와 소요 시간의 측면에서 개선의 여지가 있었다. 이를 반영하여 NAT (New Abrasion Tester) 모델을 개발하였다(Farrokh and Kim, 2018). 제안된 NAT를 국내 ${\bigcirc}{\bigcirc}$현장에 적용하였고, 기존의 방법과 비교 검토를 수행하였다. 분석 결과 ${\bigcirc}{\bigcirc}$현장의 경우 기존 방법에 비해 NAT의 예측 결과가 커터 교체 현장 실측 데이터와 잘 맞는 것으로 나타났다. NAT 모델을 향후 더 많은 현장에 적용하여 모델의 신뢰도를 높일 예정이다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.205-208
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• 2006

Damage of hydraulic concrete structures by the abrasion and erosion process is very severe and it indicates that the necessity of considering the influence of this process while designing concrete mixtures. Abrasion wear of concrete in hydraulic structures is caused by the movement of particles, water-borne debris. The resistance against erosion for high-strength self-consolidating concrete(SCC) was examined in this paper. A newly designed testing method is presented in order to quantitatively estimate the erosion of concrete. It was shown that loss of volume in abraded concrete can be explained as function of material parameters such as the amount of fly ash and blast furnace slag. Those admixtures have been widely used to reduce heat of hydration and improve resistance against sulfate attack. The results of current study can be used as a guideline in selecting the composition of concrete exposed to abrasion-wear.

• 한국재료학회지
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• 제17권11호
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• pp.601-605
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• 2007

The tribological properties of acrylonitrile-butadiene rubber (NBR) filled with two kinds of carbon black filler were examined. Different types of Semi-Reinforcing Furnace (SRF), and High Abrasion Furnace (HAF) blacks were used as filler material to test the influence of carbon black particle size on the friction and wear of NBR. Results from tribological tests using a ball on disk method showed that the smaller HAF particles were more effective for reducing the wear of NBR during frictional sliding. The hardness, elastic modulus at 100% elongation, and elongation at break were measured to examine the correlation between the effects of carbon black on the mechanical and tribological properties of the NBR specimens. The wear tracks of the NBR specimens were observed with scanning electron microscopy (SEM). The wear tracks for NBR with different ratios of SRF and HAF showed clearly different abrasion patterns. Mechanisms for the friction and wear behavior of NBR with different sizes of carbon black filler were proposed using evidence from wear track observation, as well as the mechanical and tribological test results.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.203-208
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• 1999

Friction and wear test have been performed on nylon, polyacetal, and PTFE(polytetrafluoroethylene), in reciprocating dry sliding conditions against a steel disc. According to the results, polyacetal show lowest wear rates and PTFE was found to exhibit lowest friction coefficient. The prominent wear mechanism found were adhesion and abrasion.

• 대한치과의사협회지
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• 제41권1호통권404호
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• pp.48-53
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• 2003

The purpose of this study is to report a clinical case of a patient whose vertical dimension of occlusion was lost. There are many reasons for the loss of vertical dimension and one of those can be a tooth wear problem. Thus in this article we will review shortly types of tooth wear: attrition, abrasion, and erosior. And layour the basic philosophy and principles in regaining the esthetics and function of a patient's oral condition with a history of psychological wear, through full mouth restorations.

• Journal of Korean Vacuum Science & Technology
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• 제5권1호
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• pp.1-6
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• 2001

We measured the simultaneous, time-resolved spectra of photon emission, electron emission, and frictional force during the abrasion single crystal MgO with a diamond stylus in vacuum. phE and EE signal can be detected with millisecond resolution during the wear of a single crystal MgO substrate with a diamond stylus. The emissions and wear behavior are strong function of surface condition, load and stylus velocity. Measurement on annealed vs as-received material show that the luminescence is primarily due to deformation, and the electron emission is primarily due to fracture. These emissions provide insight into the processes responsible for catastrophic failure of ceramics in wear applications.

• 한국기계가공학회지
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• 제19권12호
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• pp.34-41
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• 2020

Ready-mixed concrete is unconsolidated concrete typically transported to construction sites by using mixer trucks. A proper rotation of concrete is necessary to prevent its solidification in mixer trucks during transport: in accordance with the manufacturing method and quality inspection prescribed in KSF4009, this movement is maintained after the manufacturing of concrete in professional production plants and the addition of water, solid materials, and admixtures. Unfortunately, mixer truck parts wear out over long periods of time. In order to improve the wear resistance of the main part of mixer trucks, we used a steel plate with good wear resistance or partially added a reinforcement plate. In this study, we first tested the properties of concrete (as required for the DEM), and then carried out mixing and discharge simulations to define the actual operating conditions of mixer trucks. For each condition, we calculated the amount and location of wear. The reliability of our results was finally verified by comparing them with the measurement values. Overall, this study provided basic data for an optimal design of mixer trucks: one that would reduce the vehicles' weight and production costs.