• 대한기계학회논문집
• /
• 제14권5호
• /
• pp.1079-1086
• /
• 1990

본 연구에서는 모아레 경사격자법(moire tilted master grating method)을 개 발하여 그 유용성을 확인하고 이를 굴절 및 편심균열의 응력확대계수의 해석에 확대 적용하여 다점선정법의 적용범위를 넓히고, 또 분포균열 및 임의 형균열의 해석 가능 성을 타진하여 완성된 실험법으로서의 위치를 구축하는데 목적이 있다.

• 한국소음진동공학회논문집
• /
• 제11권6호
• /
• pp.181-192
• /
• 2001

The power flow analysis (PFA) has been performed to analyze the vibration of coupled plates excited by a point force in an arbitrary direction. The point force generates the out-of-plane vibration associated wish flexural waves and the in-plane vibration associated with longitudinal and shear waves. The energy governing equation for each type of waves was introduced and solved to Predict the vibrational energy density and intensity generated by the out-of-plane and in-plane components of the point force in an arbitrary direction. The wave transmission approach was used to consider the mode conversion at the joint of the coupled plates. Numerical results for vibrational energy density and intensity on the coupled plates were presented. Comparison of the results by PFA with exact results showed that PFA can be an effective tool to predict the spatial variation of the vibrational energy and intensity on the coupled plates at high frequencies.

• 대한기계학회논문집
• /
• 제19권4호
• /
• pp.981-989
• /
• 1995

A new weight function approach to determine SIF(stress intensity factor) using single-layer potential has been presented. The crack surface displacement field was represented by one boundary integral term whose kernel was modified from Kelvin's fundamental solution. The proposed method enables the calculation of SIF using only one SIF solution without any modification for the crack geometries symmetric in two-dimensional plane such as a center crack in a plate with or without an internal hole, double edge cracks, circumferential crack or radial cracks in a pipe. The application procedure to those crack problems is very simple and straightforward with only one SIF solution. The necessary information in the analysis is two reference SIFs. The analysis results using present closed-form solution were in good agreement with those of the literature.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
• /
• pp.269-274
• /
• 2001

Applications of Brazing in the studying fields such as High-Speed Machining are very increasing in various industry fields. Therefore, Applying to the fracture mechanics by numerical analysis method is very important to analyse the crack problem Dissimilar Materials in Brazed Interface. In this study, Stress intensity Factor (S.I.F) is analysed to investigate crack behavior on the crack tip of dissimilar materials in brazed interface such as a Hardmetal and a HSS by two dimensional(2-D) Boundary Element Method (BEM). Kelvin's solution was used as a fundamental solution in BEM analysis and stress extrapolation method was used to determine Stress Intensity Factor.

• KSTLE International Journal
• /
• 제2권1호
• /
• pp.12-16
• /
• 2001

A finite element analysis of crack propagation in a half-space due to sliding contact was performed. The sliding contact was simulated by a rigid asperity moving across the surface of an elastic half-surface containing single and multiple cracks. Single, coplanar, and parallel cracks were modeled to investigate the interaction effects on the crack growth in contact fatigue. The analysis was based on linear elastic fracture mechanics and the stress intensity factor concept. The crack propagation direction was predicted based on the maximum range of the shear and tensile stress intensity factors.

• The Korean Journal of Ecology
• /
• 제21권3호
• /
• pp.291-300
• /
• 1998

The forest vegetation of Mt. Odae based on the interspecific relationship was classified into 4 groups : Quercus mongolica, Pinus densiflora, Quercus variabilis and Patrinia saniculaefolia. Thirty-one species of Quercus mongolica group including Quercus mongolica and Acer mone, 12 species of Pinus densiflora group comprising Pinus densiflora and Spodiopogon sibiricus, 6 species of Quercus variabilis group and 4 species of Patrinia saniculaefolia were positively correlated. in the results of species ordination by principal component analysis, 7 clusters by the humidity and acidity of soil, 4 clusters by the humidity and light intensity and 7 clusters by the acidity and light intensity were formed. The plot ordination showed that the distribution of species based on the humidity, soil acidity and total organic matters was in the order of Pinus densiflora, Quercus variabilis and Quercus mongolica groups, and based on the light intensity was in the order of Quercus variabilis, Pinus densiflora and Quercus mongolica groups.

• 한국정밀공학회지
• /
• 제20권9호
• /
• pp.166-172
• /
• 2003

Vibration and Noise of air conditioner are entirely determined by compressor vibration. Compressor vibration transmitted to the enclosure of air conditioner or pipes connected compressor with heat exchanger. Enclosure generate(noise and vibration. Therefore, the analysis of compressor vibration analysis is considered significant technical issue. For the reduction of vibration of compressor, it is necessary to grasp correctly vibration transmission paths and excitation sources in the compressor shell. Because, shell ( Surface of compressor ) shows whole vibration characteristic of compressor mechanism. In this paper, vibration intensity was applied to measure vibration energy flow on the shell .From this technique, it is possible to catch the path of vibration propagation along the one cycle and the location of vibration energy sources may change with time on the shell.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 1998년도 춘계학술대회 논문집
• /
• pp.123-128
• /
• 1998

In fracture problems, stress intensity factors obtained theoretically and experimentally have been effectively utilized in the analytical evaluation of the cracks effect. The effect of surface crack of a cylindrical and a hollow cylindrical bar is investigated, as well as the effect of the thickness of a hollow cylindrical bar and inclined crack of a hollow cylinder subjected to torsion moment. In this study, stress intensity factor Km of mode III which expresses the stress state in the neighborhood of a crack tip is used. Stress analysis was conducted of the inside of a hollow cylinder in the axial direction of three dimensional crack tip subjected to torsion moment by combining the caustics method and the stress freezing method.

• 한국공작기계학회논문집
• /
• 제15권6호
• /
• pp.44-49
• /
• 2006

The use of snap-fit features is highly recommended to reduce overall product cost and manufacturing time by reducing the number of parts and eliminating assembly with conventional fasteners. Application to particular product for integral attachment using snap-fit features is needed. Alternative attachment concept for specific application has been introduced. In this study, the optimal attachment design based on the given design objectives is identified using newly developed alternative attachment concept for the specific application to LCD monitor case assembly. Integral attachment using snap-fit features applies the systematic procedure and the intensity analysis.

• 한국생산제조학회지
• /
• 제7권5호
• /
• pp.46-52
• /
• 1998

In fracture problems, stress intensity factors obtained theoretically and experimentally have been effectively utilized in the analytical evolution of the cracks effect. The effect of surface crack of a cylindrical and a hollow cylindrical bar is investigated, as well as the effect of the thickness of a hollow cylindrical bar and inclined crack of a hollow cylinder subjected to torsion moment. In this study, stress intensity factor Km of mode III which expresses the stress state in the neighborhood of a crack tip is used. stress analysis was conducted on the inside of hollow cylinder inthe axial direction of three dimensional crack tip subjected to torsion moment by combining the caustics method and the stress freezing method.