- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Numerical investigation of atherosclerotic plaque rupture using optical coherence tomography imaging and XFEM
摘要： Myocardial infarction contributes to most fatalities in which atherosclerotic plaque disruption is the underlying pathology. From the mechanics view point, the pulsatile blood flow in the arteries resembles a fatigue environment and generates stresses that affect the rupture of the atherosclerotic plaque. In this context, patient-specific optical coherence tomography (OCT) was used to develop the fatigue crack growth behavior. The impact of location specific morphological features and their relative effect on plaque life were discussed. EXtended Finite Element Method (XFEM) and Paris’ Law were employed to investigate the fatigue crack growth. Twelve 2D slices from six patients were reconstructed for studying the fatigue crack growth behavior. Our results indicate that plaque life decreases with an increase in pulse pressure and 53.5% of the total cracks initiated at various locations on the lumen lead to rupture. 73.7% of the rupture locations did not have calcifications. Correlation between the location specific morphology and the rupture indicates that for a 1 mm increase in the fibrous cap thickness there is a large decrease in the odds of rupture [0.163 (0.073; 0.363)], p-value < 0.0001; and for a 1 mm2 increase of the calcification area, there is a decrease in the odds of rupture by 0.719 (0.619; 0.835), p-value < 0.0001. In conclusion, the XFEM technique can be used to study the fatigue behavior of the atherosclerotic plaque that depends on the combined effects of plaque constituents and their morphology. It may help to better assess plaque vulnerability and make more accurate predictions for plaque rupture.
关键词： XFEM,Fatigue crack growth,Atherosclerotic plaque rupture,Optical coherence tomography,Paris’ Law
更新于2025-09-10 09:29:36
-
Non-contact fatigue crack detection in civil infrastructure through image overlapping and crack breathing sensing
摘要： Fatigue cracks are of critical structural safety concern in civil infrastructure. Many existing fatigue crack sensing methods are contact-based, hence extensive human operation is necessary for sensor and/or actuator deployment. In this study, we propose a vision-based non-contact approach to detect fatigue cracks through image overlapping. We treat crack breathing behavior, the small cyclic movement of the crack perpendicular to the crack path under repetitive fatigue loads, as a robust indicator for crack identification. The differential image features provoked by a breathing crack can be extracted, enhanced, and visualized through a series of image processing techniques. The performance of the proposed approach is experimentally validated through two laboratory setups including a small-scale steel compact specimen and a large-scale bridge to cross-frame connection specimen. Test results demonstrate the capability of the proposed approach in reliably identifying the fatigue crack, even the true crack is surrounded by other non-crack features.
关键词： Computer vision,Bridges,Civil infrastructure,Feature matching,Non-contact sensing,Image processing,Structural health monitoring,Image registration,Breathing crack,Fatigue crack detection
更新于2025-09-04 15:30:14