Differential quadrature method DQM is proposed for the numerical solution of oneand twospace dimensional hyperbolic telegraph equation subject to appropriate initial and boundary conditions. Both polynomial-based differential quadrature PDQ and Fourier-based differential quadrature FDQ are used in space directions while PDQ is made use of in time direction. Numerical solution is obtained by usi...

Terrain modeling is a fast growing field with many applications such as computer graphics, resource management, Earth and environmental sciences, civil and military engineering, surveying and photogrammetry and games programming. One of the most widely used terrain model is the Digital Elevation Model (DEM). A DEM is a simple regularly spaced grid of elevation points that represent the continuo...

A method of preparing grid deviation maps for the representation of the areal composition variations in granitic bodies is described. A comparative study of this method and the trend surface method by using the data of forty-five modal analyses of Bahalda hornblende granodiorite indicates greater effectiveness of the former in several respects. THE point count method of modal analysis has made ...

The standard MR protocol of the spine included sagittal T1weighted and T2-weighted fast spin echo. Volume measurements are made by using a transparent template to overlay a grid of regularly spaced points over MRI scans of randomly selected patients (Figure 1). This point is counted as the full contact of the counter. Counts are made three times. The double or middle number is used. The volume ...

It is demonstrated that grouping together features which satisfy a geometric relationship can be used both for (automatic) detection and estimation of vanishing points and lines. We describe the geometry of three commonly occurring types of geometric grouping and present eecient grouping algorithms which exploit these ge-ometries. The three types of grouping are : (1) a family of equally spaced...

The ability to calculate traveltimes and amplitutdes of seismic waves is useful for many reflection seismology applications such as migration and tomography. Traditionally, ray tracing (cerveny et al., 1977; Julian, 1977), paraxial methods (Claerbout, 1971), or full-wave methods (Alterman and Karal, 1968) are used for such calculations. These methods have in common considerable computational ex...

in this paper high order multidimensional positive definite advection transport algorithm (mpdata) and compact finite difference methods are applied to one (1-d) and two-dimensional (2-d) advection equation. mpdata methods are designed based on upwind scheme using anti-diffusive velocity that compensates diffusivity of upwind method. in high order compact method one implicit relation between a ...

Non-rigid image registration is an essential tool required for overcoming the inherent local anatomical variations that exist between images acquired from different individuals or atlases, among others. This type of registration defines a deformation field that gives a translation or mapping for every pixel in the image. One popular local approach for estimating this deformation field, known as...

It is well known that the grid cell size of a raster digital elevation model has significant effects on derived terrain variables such as slope, aspect, plan and profile curvature or the wetness index. In this paper the quality of DEMs derived from the interpolation of photogrammetrically derived elevation points in Alberta, Canada, is tested. DEMs with grid cell sizes ranging from 100 to 5 m w...