• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.143-151
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• 1999

The shape of surface micro-crack is very irregular due to nonhomogeneous microstructure but is very important in respect to qualitative estimation of fatigue life. Fractal geomety can quantify the shape of surface mciro-crack. Fractal dimension is measured for surface micro-cracks with coast line and box counting method and estimates cycle ration in Al 2024-T3. The average fractal dimension $D_{favg}$ of surface micro-cracks has 3-parameter weibull distribution and location parameter is nearly constant but shape parameter decreases as cycle ration increases. The fractal dimension by coast line method is measured for individual surface micro-crack but the fractal dimension by box countin method is measured for all the surface micro-cracks under sampling area. Therefore, This paper shows fractal dimension $D_{fb}$ can predict cycle ratio $N/N_f$ more convenient than fractal dimension $D_{favg}$.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.115-123
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• 1998

The morphological analysis of wear particle is a very effective means for machine condition monitoring and fault diagnosis. In order to describe morphology of various wear particle, the wear test was carried out under different experimental conditions. And fractal descriptors was applied to boundary and surface of wear particle with image processing system. These descriptors to analyze shape and surface wear particle are shape fractal dimension and surface fractal dimension. The shape fractal dimension can be derived from the boundary profile and surface fractal dimension can be determined by sum of intensity difference of surface pixel. The morphology of wear particles can be effectively obtained by two fractal dimensions.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.53-58
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• 2001

Fractal dimension is the method to measure the roughness and the irregularity of something that cannot be defined obviously by Euclidean dimension. And the analysis method of this dimension don't need perfect, accurate boundary and color like analysis lot diameter, perimeter, aspect or reflectivity of wear particles or surface. If we arranged the morphological characteristic of various wear particle by using the characteristic of fractal dimension, it might be very efficient to the diagnosis of driving condition. In order to describe morphology of various wear particle, the wear test was carried out under friction experimental conditions. And fractal descriptors was applied to boundary and surface of wear particle with image processing system. These descriptors to analyze shape and surface wear particle are boundary fractal dimension and surface fractal dimension.

• Tribology and Lubricants
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• v.18 no.2
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• pp.147-152
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• 2002

The morphological analysis of wear particle is a very effective means fur machine condition monitoring and fault diagnosis. In order to describe morphology of various wear particle, the wear test was carried out under friction experimental conditions. And fractal descriptors was applied to boundary and surface of wear particle with image processing. These descriptors to analyze shape and surface of wear particle are shape fractal dimension and surface fractal dimension. The boundary fractal dimension can be derived from the boundary profile and surface fractal dimension can be determined by sum of intensity difference of surface pixel. The morphology of wear particles can be effectively obtained by two fractal parameter.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.30-35
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• 2001

The morphological analysis of wear particle is a very effective means for machine condition monitoring and fault diagnosis. In order to describe morphology of various wear particle, the wear test was carried oui under friction experimental conditions. And fractal descriptors was applied to boundary and surface of wear particle with image processing system. These descriptors to analyze shape and surface wear particle are share fractal dimension and surface fractal dimension. The boundry fractal dimension can be derived from the boundary profile and surface fractal dimension can be determined b)r sum of intensity difference of surface pixel. The morphology of wear particles can be effectively obtained by two fractal dimensions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.149-151
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• 2006

The surface properties of electrical devices studied by fractal phenomenon were investigated. The SEM photographs of devices surface were changed by binary code and it were analyzed by fractal dimension. The void of devices surface was found by fractal program. The relation between grain density and electrical properties are able to expect to fractal dimension. The grain size in varistors surface was decreased by increasing of oxide antimony addition. The fractal dimension and electrical properties of devices surface was related to between grain boundary and grain density. The grain size was decreased by increasing of fractal dimensions.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.387-392
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• 2005

The research was performed to predict the potential landslide with roughness index. It was known that fractal dimension and surface area index can be represented the topography, specially when the natural slopes were rough or rugged. A test site was selected and fractal dimension and surface area index were calculated from the irregular triangle network. Fractal dimension were ranged between $2.016{\sim}2.046$ and surface area index $1.56E+07{\sim}2.59E+07$. Surface area index increased as fractal dimension increased. Slope stability was calculated by infinite slope stability analysis model and was compared to slope stability by fractal and surface area index. In the result, unsafe zones where slope stability is under 1.1 were $5.11{\sim}6.25%$ for the test site. It can be said that fractal dimension and surface area index are a good index to evaluate the slope stability because when fractal dimension and surface area index are greater, then stability of the site is more unsafe.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.257-258
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• 2002

The surface morphology of oil-lubricated surface for hydraulic piston motor is believed to be extremely effective in contact mechanics. adhesion. friction and wear. In order to describe morphology of various rubbed surface on driving condition, the wear test was carried out under different experimental conditions in oil-lubricated system. And fractal descriptors was applied to rubbed surface of hydraulic members with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. Morphology of rubbed surface can be effectively obtained by fractal dimension.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05a
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• pp.47-51
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• 2001

The structural properties of varistors surface studied by fractal phenomenon were investigated to verify the relations of electrical characteristics. The SEM photograph of varistors surface were changed by binary code and the grain shape of that were analyzed by fractal dimension. The void of varistors surface was found by fractal program. The relation between grain density and electrical properties depend on fractal dimension. The grain size in varistors surface was decreased by increasing of oxide antimony addition. The grain size of devices by oxide antimony addition were from 5 to $10[{\mu}m]$. The fractal dimension and electrical properties of varistors surface was related to between grain boundary and grain density. The grain size was decreased by increasing of fractal dimensions.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.240-246
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• 1999

The determination of surface topography is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe topography of various frictional surface, the wear test was carried out under different experimental conditions in dry friction. And fractal descriptors was applied to frictional surface of laser modified steel with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. Topography of frictional surface can be effectively obtained by fractal dimensions.