• Title/Summary/Keyword: Wear pattern

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A Basic Study on Functional Friction Surface of Artificial Joints (내마모성이 향상된 기능성 표면구조를 갖는 인공관절에 관한 기초적인 연구)

  • ;T. Yuhta
    • Journal of Biomedical Engineering Research
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    • v.22 no.6
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    • pp.519-526
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    • 2001
  • At present. about 0.3 million and more THRs (Total Hip Replacement) in a rear are being done worldwide. The increase in mechanical failure with the increase in THR, required more revisions. Revisions compensate mainly the wear of the artificial joint frictional surface and the loosening of the cup and stem. According to recent researches, loosening is mainly due to wear debris UHMWPE (Ultra High Molecular Weight Polyethylene) from frictional surfaces . To overcome the wear problems associated with artificial joint materials , new surface structures with regular Patterns were designed and fabricated The lubrication Properties were examined to evaluate the wear of the frictional surfaces. The surface structure manifested a Pattern of "dents" with a 0.2-1.0 mm of diameter and 0.6-2.0 mm of Pitch. From the friction test of the SUS316L vs UHMWPE using the frictional tester, we found that the lubrication Performance was improved due to of drastically reduced amount of abrasion. There were optimum sizes for the diameter and the pitch of the Pattern. The results demonstrated that the lubrication properties could be improved by Patterning of the frictional surfaces. The surface Patterning was effective in preventing wear of the frictional surfaces, and the life of an artificial joint could be extended with such Patterning.

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Study of Patterns According to Changes in Shoulder Angle in Drop Shoulder Sleeves (드롭숄더 슬리브의 어깨각도 변화에 따른 패턴 연구)

  • Ha-Eun Lee; Eun-Hye Lee;Jeong-Woo Choi
    • Journal of the Korea Fashion and Costume Design Association
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    • v.26 no.2
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    • pp.15-32
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    • 2024
  • Modern fashion manifests in forms that mirror the diverse lifestyles and personalities of consumers. It transcends mere aesthetic designs and embodyies practicality. There is a preference for comfortable, highly functional attire, leaning towards easy wear. Casual wear, in particular, embraces a sense of freedom not found in standard business attire. It seeks a comfortable, natural silhouette through tactile fabrics rather than sportswear. Loose, drop shoulder sleeves enhance comfort and mobility and often become key elements in casual wear designs. Given that clothing must balance aesthetics with functionality, especially across various activities, it is natural to prioritize functional design. Research on patterns suited for dynamic conditions is imperative. The rise of drop shoulder styles necessitates the development of corresponding sleeve patterns. It is crucial to differentiate pattern drafting methods due to the resulting silhouette variations. This study aims to categorize drop shoulder pattern drafting techniques based on shoulder extension and angle dimensions. Each method will be examined, and drop shoulder sleeve patterns and wear forms will be studied using a 3D virtual system. This research holds significance in providing valuable insights and foundational data for designing diverse drop shoulder sleeve patterns, contributing to their practical development and advancement.

Applicaion of Neural Network for Machine Condition Monitoring and Fault Diagnosis (기계구동계의 손상상태 모니터링을 위한 신경회로망의 적용)

  • 박흥식;서영백;조연상
    • Tribology and Lubricants
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    • v.14 no.3
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    • pp.74-80
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    • 1998
  • The morphologies of the wear particles are directly indicative of wear process occuring in the machine. The analysis of wear particle morphology can therefore provide very early detection of a fault and can also ofen facilitate a dignosis. For this work, the neural network was applied to identify friction coefficient through four shape parameters (50% volumetric diameter, aspect, roundness and reflectivity) of wear debris generated from the machine. The averages of these parameters were used as inputs to the network. It is shown that collect identification of friction coefficient depends on the ranges of these shape parameters learned. The various kinds of the wear debris had a different pattern characteristics and recognized relation between the friction condition and materials very well by neural network. We discuss how the network determines difference in wear debris feature, and this approach can be applied for machine condition monitoring and fault diagnosis.

Identification of Friction Condition with Neural Network (신경회로망에 의한 마찰상태의 식별)

  • 조연상;서영백;박흥식;전태옥
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1998.04a
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    • pp.83-90
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    • 1998
  • The morphologies of the wear debris are directly indicative of wear processes occuring in machinery and their severity. The neural network was applied to identify friction condition from the lubricated moving system. The four parameter(50% volumetric diameter, aspect, roundness and reflectivity) of wear debris are used as inputs to the network and learned the friction coefficient. It is shown that identification results depend on the ranges of these shape parameter learned. The three kinds of the wear debris had a different pattern characteristic and recognized the friction condition and materials very well by neural network. We dicuss between the characteristic of wear debris and the friction coefficient and how the network determines difference in wear debris feature.

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Decision of Operating Condition in the Lubricated Moving System by Neural Network (신경회로망에 의한 윤활 구동계의 작동조건 판정)

  • 조연상;문병주;박흥식;전태옥
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1997.10a
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    • pp.135-144
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    • 1997
  • This wear debris can be harvested from the lubricants of operating machinery and its morphology is directly related to the damage to the interacting surfaces from which the particles originated. The morphologies of the wear particles are therefore directly indica- rive of wear processes occuring in machinery and their severity. The neural network was applied to identify wear debris generated from the lubricated moving system. The four parameter(50% volumetric diameter, aspect, roundness and reflectivity) of wear debris are used as inputs to the network and learned the friction condition of five values(material 3, applied load 1, sliding distance 1). It is shown that identification results depend on the ranges of these shape parameter learned. The three kinds of the wear debris had a different pattern characteristic and recognized the friction condition and materials very well by neural network. We dicuss how the network determines difference in wear debris feature, and this approach can be applied to condition diagnosis of the lubricated moving system.

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Analysis on the Running Stability of Rolling-stock according to Wheel Profile Wear (차륜답면형상 마모에 따른 차량 주행안정성 영향 분석)

  • Hur, Hyun-Moo;You, Won-Hee
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.5
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    • pp.551-558
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    • 2011
  • To analyze the effect of wear of wheel profile on the running stability of rolling-stock, theoretical and experimental studies were conducted on the profiles used in conventional lines. In experiment using 1/5 scale model to verify the results of the theoretical analysis, the test results of the critical speed for worn wheel profile samples show similar trend. In case of the conical type wheel profile(Profile 40), the equivalent conicity is increased with flange wear. But in case of the arc type wheel profile(Profile 20h), the equivalent conicity is decreased with flange wear. And the critical speed of the bogie was inverse proportion to the equivalent conicity. It is shown that the variation of the critical speed with the wheel wear could be changed according to the design concept and wear pattern of wheel profile. Results of the theoretical and experimental studies are discussed here.

Slurry Flow Simulation in the Separation Stage of Screw Decanter (스크류 데칸트 분리단 내부에서의 유동 해석)

  • Baek, Yeong-Su;Na, Eun-Su;Park, Jae-Deok
    • 연구논문집
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    • s.31
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    • pp.53-63
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    • 2001
  • Numerical investigation based on the control-volume using finite-difference method has been made by the development of computer program in order to figure out the pattern of the flow field inside screw decanter. The typical flow pattern inside screw decanter is characterized by the two strong recirculation zones separated by the main stream from slurry discharge hole to exit. These recirculation regions and flow pattern are strongly influenced by the centrifugal force and the change of the value of slurry viscosities, that is,500, 1,000 and 3,000cp respectively. The wear of screw decanter appeared experimentally in two spots; one is near the circumferential area of the slurry discharge hole and the other is on the decanter blades at a certain height from the bottom to a different degree after the continuous long-term operation. These wears are partly explained by the flow pattern and the strong turbulence intensity near the recirculation attachment region.

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Consumer Perceptions, Evaluations and Attributes of Outdoor Wear Differentiation (아웃도어웨어 차별화에 대한 인식, 평가 및 차별화 속성)

  • Yoo, Hwa-Sook
    • Fashion & Textile Research Journal
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    • v.18 no.1
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    • pp.27-37
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    • 2016
  • This study examined consumer perceptions towards outdoor wear differentiation and product attributes for outdoor wear differentiation to develop an outdoor wear differentiation strategy. It also investigated how consumer's evaluated product attributes according to consumer's demographic characteristics. Data were acquired from a survey of 454 adult respondents aged over 20 that was analyzed with descriptives, frequency, t-test, one-way ANOVA, factor analysis, and reliability. The results were as follows. First, it showed that consumers did not have a positive or a negative perception toward outdoor wear differentiation, and they thought outdoor wear should be differentiated. Those married and older tended to think that outdoor wear should be differentiated more than that for those single and younger. Consumer evaluations were significantly different on the necessity of outdoor wear differentiation according to age and total income. Second, consumers assessed that color, pattern and textiles had similar characteristics among outdoor wear brands; in addition, brand recognition and brand image had very different characteristics. Third, product attributes for outdoor wear differentiation were service and store, product quality, brand and popularity, and product designs with mean values of product quality, product design, service and store, and brand and popularity, respectively. Fourth, consumers were significantly different in the importance assessment of product attributes for differentiation according to gender, marital status and age.