Yasuhiko Hara

Quantitative damage assessment of concrete structures based on 3D laser scanning

Recently scaling damages of concrete structures have become apparent and it is now investigated to develop a method for quantitatively assessing the damages. In this paper, we propose a beneficial method for this purpose based on long-distance 3D laser scanning. In our proposed method, original shapes of the concrete structures before to be damaged are estimated on their laser scanned data by region growing, the distances to the estimated shapes are computed at each scanned point, and then their surface concavity and convexity are quantitatively evaluated based on the computed distance. We demonstrate the effectiveness of our proposed method from various experiments on real scanned data of concrete structures with scaling damages.

Proposal of Method Estimating Deformation of Printed Characters Utilizing GA

A method is proposed for estimating deformation of printed characters. In this method, displacement, rotation, dilation/erosion, and magnification are taken to be character-deformation parameters, and character deformation is estimated by measuring changes in these deformation parameters with respect to a standard character. To measure the deformation from a standard character, the target character is deformed using a genetic algorithm, the deformed character is matched up with a standard character, and deformation parameters are determined for the best match between two characters. An experiment performed on several characters demonstrated that these deformations as well as missing and excess sections could be measured.