This paper analyzes the reconstruction of diffusion and absorption parameters in an elliptic equation from knowledge of internal data. In the application of photoacoustics, the internal data are the amount of thermal energy deposited by high frequency radiation propagating inside a domain of interest. These data are obtained by solving an inverse wave equation, which is well-studied in the lite...

We present a method to reconstruct from one or more images a scene that is rich in planes, alignments, symmetries, orthogonalities, and other forms of geometrical regularity. Given image points of interest and some geometric information, the method recovers least-squares estimates of the 3D points, camera position(s), orientation(s), and eventually calibration(s). Our contributions lie (i) in a...

Geometrical optical projection three-dimensional profile measurement has the advantages of non-contact, non-destructive, and fast data acquisition. Its system is most promising kind macro-optical profiler. The thesis analyzes laser light source image acquisition processing, designs tomographic reconstruction display experimental imaging system, conducts theoretical analysis its theory, quality ...

The purpose of this paper is to examine representative examples of realistic three-dimensional models for porous media by comparing their geometrical and transport properties with those of the original experimental specimen. The comparison is based on numerically exact evaluations of permeability, formation factor, porosity, specific internal surface, mean curvature, Euler number, local porosit...

Many high-resolution surfaces are created through isosurface extraction from volumetric representations, obtained by 3D photography, CT, or MRI. Noise inherent in the acquisition process can lead to geometrical and topological errors. Reducing geometrical errors during reconstruction is well studied. However, isosurfaces often contain many topological errors in the form of tiny handles. These n...

The 3D trajectory of the ball is one of the most important performance indicators in ball games. However, it often cannot be measured because of the requirements: synchronized cameras and control points within the playing field. Thus, this paper proposes a method that reconstructs the 3D trajectory of a ball with unsynchronized cameras. The proposed method consists of ball detection, camera cal...

This study focuses on the development of a new module for a more accurate determination of geometrical properties of aggregates. A laser-based imaging system has been developed for the shape characterization of aggregates by using various digital image analysis techniques. By using this system it is possible to create a three-dimensional (3D) image form of aggregate particles. The system has be...

The Raychaudhuri equation is derived by assuming geometric flow in space–time M of n+1 dimensions. turns into a harmonic oscillator form under suitable transformations. Thereby, relation between geometrical entropy and mean geodesic deviation established. This has connection to chaos theory where the trajectories diverge exponentially. We discuss its application cosmology black holes. Thus, we ...

In orthopaedic surgery, intra-operative bone machining and assembly of osseous fragments are two very important research areas. One of the most challenging applications is the treatment of malignant osseous tumors within the pelvis due to its complex tri-dimensional geometry. The conventional surgical procedure includes tumoral resection (cutting of the osseous tumor) and reconstruction by allo...