Simulate the laserinduced ablation in air and in water to compare the induced stress between the two ablation regimes First, the simulation is carried out to reconstruct the experimental images obtained by photoelasticity imaging technique for in-air and in-water ablation. Then, the Von Mises Stress is elucidated from simulation for each regime. The result confirms the stress enhancement effect of water layer and showed that the stress is increased by at least two orders of magnitude if the ablation is carried in water.
Photoelasticity images of laser peening using sacrificial coating were simulated by the Finite Element Method. The Von Mises stress distribution in the coated target is deduced from the simulated images and is compared with the stress-induced in the non-coated target. The result shows that sacrificial coating can enhance the induced stress by a factor of 1.2.
The observation was conducted using high-speed laser stroboscopic videography in photoelasticity mode. We showed the bubble contracted faster in the vertical direction and formed a flat bubble at the minimum contraction. At the collapse, the bubble emitted multiple shock waves. The dynamics of the bubble during contract phase and the emission of multi shock waves were discussed in details.
This study aims at investigating students’ difficulties that often occur in learning Conference Interpretation and give some suggested solutions. Hopefully, the study will help learners find out and overcome their problems in learning this subject.
This study develops an alternative model based on image edge detection, projection integral, and logistic regression approaches for recognizing and categorizing cracks on concrete surface. The integrated model has been developed using Visual C#.NET and tested with 200 real-world image samples.
This study develops a computer program and implements the iteratively reweighted least squares (IRLS) used for fitting multiple linear regression models. The capability of the combined model, IRMLR, is demonstrated using two artificial datasets and two real-world applications. The results indicate that the IRMLR model can be a useful tool to assist civil engineers in the task of data modeling.
This study aims at developing a computer vision tool to segment images capturing surface of reinforced concrete structures. The image processing technique of Gabor filter is used with k-Means clustering algorithm and principal component analysis to automatically segment damages on concrete surface including spall, crack, bughole, and stain.
Present new results on the synthesis of nitrogen-doped GQDs (NGQDs) and sulfur-doped GQDs (S-GQDs) and their respective optical properties such as absorption spectra, fluorescence, and Raman spectra. The fluorescent mechanisms of GQDs, N-GQDs, and S-GQDs will also be clarified and explained.
