Medial surface, the skeletal abstraction of a solid shape, can be used in applications such as shell (solid) mesh generation, robot path planning, and feature recognition. Unfortunately, computing the medical surface is very difficult. Those few algorithms proposed invariably need to solve systems of non-linear polynomial equations, which requires complicated numerical techniques. Recently, an ...

Traditional approaches to analyzing experimental functional magnetic resonance imaging (fMRI) data entail fitting per-voxel parameters to explain how the observed images reflect the thoughts and stimuli a participant experienced during the experiment. These methods implicitly assume that voxel responses are independent and that the unit of analysis should be the voxel. However, both of these as...

preference in human primary visual cortex (V1). Each line corresponds to a different voxel (a 2 2 2 mm cube of cortex) in V1; signals from each voxel were measured using functional magnetic resonance imaging. Orientation preference was measured by showing human observers stimuli like the oriented grating shown in the background. The location of each line represents the location in the visual fi...

Research of virtual surgical operations has advanced in recent years based on virtual reality technology. One basic operation is virtual cutting simulation. In order to realize the virtual cutting, there are two types of research, i.e. using a voxel model and a polygonal model.The voxel model expresses volume and is made by a small cube size. The polygonal model expresses the surface and is con...

Meteorological simulation tools to model gas exchange phenomena within forests require well defined information of forest structure (e.g., 3D forest models) as a basis for the computation of the turbulent flow shaped by the drag of the vegetation. The paper describes techniques to obtain 3D data describing forest stands from dense terrestrial laser scanner point clouds. In a first step, stems a...

Diffusion tensor imaging (DTI) tractography provides noninvasive measures of structural cortico-cortical connectivity of the brain. However, the agreement between DTI-tractography-based measures and histological 'ground truth' has not been quantified. In this study, we reconstructed the 3D density distribution maps (DDM) of fibers labeled with an anatomical tracer, biotinylated dextran amine (B...

Functional Magnetic Resonant Imaging (fMRI) is a non-invasive imaging technique used to study the brain. Neuroscientists have developed various algorithms to determine which voxels of the images are active. Most of these algorithms, operating on the signal of each voxel separately, are referred to as the voxel-by-voxel detectors. Among those voxel-by-voxel detectors, paired T-test and General L...