• 한국철도학회논문집
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• 제14권2호
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• pp.100-108
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• 2011

본 논문은 고속철도 디스크 브레이크용 유연 제동 패드의 성능 향상을 위해 구조적 안정성 검토와 신뢰성에 대한 연구를 수행하였다. 연구에서는 유연패드의 구조 해석 과정을 거쳐 개선된 모델을 얻어내었으며, 실제 크기와 동일한 1/2 모델을 가지고 구조적 안전성을 확인하였다. 또한, 축소 시편을 제작하여 모달 시험과 스트로크 및 내구성 시험을 수행하여 동 특성과 기계적 안정성을 확인하였다. 샤시 다이나모 장비와 열 적외선 캠코더를 이용하여 유연패드에 대하여 회전 속도에 따른 열섬 발생 현상을 측정하고, 디스크와 패드 사이의 균일한 접촉 능력을 확인하였다. 또한, 제동 시 유연패드에 안정적인 온도 분포가 이루어지는 것을 확인할 수 있었다. 이와 같은 결과를 토대로 제안된 유연패드의 구조 안정성 및 열에너지 방출 효과 등의 장점을 확인하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (1)
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• pp.481-483
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• 1998

객체지향 방법에 의한 소프트웨어 개발은 문제해결의 적용 측면에서 많은 유연성을 가지고 있으며 사용자 환경의 많은 요구조건을 만족시키고 있다는 것은 이미 공인된 사실이다. 그러나 잘못 적용한 컴퍼넌트는 객체지향 시스템 개발에 많은 제한을 가져올 수 있다. 본 연구에서는 시스템 구현 시 연속적으로 변화되는 속성들과 적용방법들이 변화하는 것을 관리하여 새로운 시스템 개발에 필요한 컴퍼넌트의 선택과 행위성을 이해하는 문제를 해결하고자 퍼지 메커니즘을 이용한 디스크립터 분류와 분석도구의 적용에 관한 방법론을 제시하고자 한다.

• 한국생산제조학회지
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• 제9권5호
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• pp.13-24
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• 2000

• 한국생산제조학회지
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• 제10권2호
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• pp.12-22
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• 2001

• 한국정밀공학회지
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• 제13권7호
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• pp.158-166
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• 1996

In this study, a flexible disk grinding process is applied in order to produce high precision product. A new model was developed considering feed motion along horizontal and vertical direction. Different types of feed speed variation was tested with respect to distinct process stages in order to achieve flat surface. It was observed that highest order polynomial form for both horizontal and vertical feed speed variation among the proposed categories produced surface close to flat one. Disk deflection trend during the process was visualized confirming the proposed scheme. Cutting force and VRR(volume removal rate) was observed as an aid to process planning.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.314-319
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• 2000

The working surface of a flexible grinding disk was characterized by means of an image processing, in which a picture of a disk surface was taken by the CCD camera and analyzed with the personal computer. As process conditions, depth of cut was changed to be 2 and 4 mm. From the captured image circles marked on the disk was regenerated using the edges detected with scale space filtering. In order to correlate the level of deformation to the distortion of the circles, intervals between each circle have been analyzed. Notable correlation has been observed between the intervals and the process conditions.

• 한국공작기계학회논문집
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• 제16권6호
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• pp.125-132
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• 2007

Inherent dynamic interaction between flexible disk and workpiece creates partially non-flat surface profile. A flat zone was defined using minimum depth of engagement. Several key parameters were defined to explain the characteristics of the zone. Process conditions including disk rotation speed, initial depth of cut and feed speed were varied to produce product profile database. Correlation between key factors was examined to find the characteristic dependencies. Trends of key parameters were displayed and explained. Higher flat zone ratio was observed for lower depth of cut and higher disk rotation speed. Ratio of minimum depth of cut against target depth of cut increased for higher feed speed and disk rotation speed but was insensitive to the depth of cut variation. The process transition was visualized by continuously displaying instantaneous orientation of the deflected disk and the location of key parameters were clearly marked for comparison.

• 한국공작기계학회논문집
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• 제17권5호
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• pp.123-130
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• 2008

In order to clarify detailed mechanism of the flexible disk grinding system, workpiece length was introduced and its performance was evaluated. Flat zone ratio increased as the workpiece length increased. Increasing wheel speed and depth of cut also enhanced process performance by producing larger flat zone ratio. Neural network system was successfully applied to predict minimum depth of engagement and flat zone ratio. An additional input parameter as workpiece length to the neural network system enhanced the prediction performance by reducing error rate. By rearranging the Input combinations to the network, the workpiece length was precisely predicted with the prediction error rate lower than 2.8% depending on the network structure.

• 한국생산제조학회지
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• 제9권1호
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• pp.81-87
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• 2000

A variable cutting speed control model was developed to be implemented for the flexible disk grinding process Control algorithm was based on the error referred by the discrepancy between current disk angle and intended one that are pro-posed to produce desired resulting depth of cut. Controller was implemented in two different aspect One was to initiate the control law from the beginning while the other was to activate as soon as the disk start to produce ground surface i.e. The beginning of the between edges stage. Several performance analysis were conducted comparing various process parameters such as cutting force disk angle depth of cut and disk speed with respect to process transition time Tentative results revealed that controller implemented from the earlier stages of the process showed better performance than the other revealed that controller implemented from the earlier stages of the process showed better performance that the other.

• 한국산학기술학회논문지
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• 제12권4호
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• pp.1775-1780
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• 2011

본 논문은 요추부의 손상이 심할 경우 척추경 나사시스템이라는 인공물을 이용하여 수술을 하게 되는데, 이때 적용되는 척추경 나사시스템의 역학특성을 분석하였다. 척추경 나사 시스템으로 고정된 디스크는 일반적으로 퇴행되지만, 제안된 플렉시블 로드를 적용할 경우 고정된 디스크에 유연성(6도 이하)을 부여할 수 있어 디스크가 퇴행되는 것을 막아주는 역할을 할 수 있다. 본 연구에서는 유한요소 해석을 이용하여 플렉시블 로드를 적용한 척추경 나사 시스템의 역학특성을 분석한 결과, 10N 이하의 척추 거동에서 플렉서블 로드는 항복 응력 이내의 응력 분포가 나타남을 알 수 있었으며. 분석된 플렉시블 로드 시스템은 실제 제작 후 인장, 압축 비틀림 등의 척추경 나사 시스템 공인 규격 실험(ASTM F 1717)을 수행하여 항복 응력 이내의 안정적인 작동성을 검증하였다.