Representations of real objects by corresponding digital pictures cause an inherent loss of information. There are infinitely many different real shapes with an identical corresponding digital picture. The problem we are interested in is how effciently the gravity center (or centroid) of a planar convex region whose boundary has a continuos third derivative and positive curvature (at every poin...

Recent advances in the implementation of spatial econometrics model estimation techniques have made it desirable to compare results, which should correspond between implementations across software applications for the same data. These model estimation techniques are associated with methods for estimating impacts (emanating effects), which are also presented and compared. This review constitutes...

In dynamical systems with divided phase space, the vicinity of the boundary between regular and chaotic regions is often “sticky,” that is, trapping orbits from the chaotic region for long times. Here, we investigate the stickiness in the simplest mushroom billiard, which has a smooth such boundary, but surprisingly subtle behaviour. As a measure of stickiness, we investigate P (t), the probabi...

This paper is concerned with the motion of electrically charged particles in \curved" inn-nite strip. The equations of motion are ' = with initial and boundary conditions, where ' is the electric potential, is the particle trajectory, P is the charge distribution, and J is the Jacobian. The lower boundary ? 0 of the strip is grounded. Therefore, once a particle reaches ? 0 ; it loses its charge...

where ∂i = ∂/∂x i and D = ∪ 0≤t≤T {t}×Dt, Dt ⊂ R. Here V k = δvi = vk and we use the summation convention over repeated upper and lower indices. The velocity vector field of the fluid is V , p is the pressure and Dt is the domain the fluid occupies at time t. We also require boundary conditions on the free boundary ∂D; p = 0, on ∂D, (1.3) (∂t + V ∂k)|∂D ∈ T (∂D), (1.4) Condition (1.3) says that...

Believing that figural zoom invariance and the cross-figural boundary linking implied by medial loci are important aspects of object shape, we present the mathematics of and algorithms for the extraction of medial loci directly from image intensities. The medial loci called cores are defined as generalized maxima in scale space of a form of medial information that is invariant to translation, r...

avo theory was introduced around 20 years ago. in recent years, this technique was become to a major tool in hydrocarbon sources exploration. by the help of this method with the suitable understanding from underground layers and knowing how to use this technology, quantitative specifications of reservoir can be recognized. avo analysis is a seismic technique that by using of pre-stack data, est...