seismic coherency is a measure of lateral changes in acoustic impedance that are caused by variations in structure, stratigraphy, lithology, porosity, and fluid content. seismic coherency is a geometrical attribute that establishes temporal and lateral relationships with other attributes. seismic coherency can be defined by coherency attributes. when coherency attributes are applied to seismic ...

When the x-ray of an object is taken, an x-ray of known intensity is emitted from an x-ray source and then the intensity is measured at a sensor. The decrease in intensity is related to how much \stu " is between the source and the sensor. Mathematically, \how much stu " is along a line is the line integral of a function describing where \stu " is along that line. Tomography is the study of wha...

In line transect sampling, data are collected continuously along the path travelled. These data are then used to estimate some characteristic of an entire region. We model the characteristic of the region as a linear functional of Z(), a realization of a random eld, and our data as the values of Z(x) for x along the path. We study how to estimate the characteristic of interest and how to choose...

Motivated by questions on tensor rank, this work concerns the following unexpected result concerning Waring decompositions of plane quartics containing a double line, along with some preparatory and additional remarks. Let x, l1, . . . , l7 be linear forms and q a quadratic form on a vector space of dimension 3. If xq = l 1 + · · · + l 7 and the lines l1 = 0, . . ., l7 = 0 in P intersect x = 0 ...

If we start with Einstein’s beautiful hypothesis that test particles in gravitational field move along geodesic lines of some Riemannian spaces V4, it is natural to expect that the differential equations for finding the metric tensor gαβ(x) for a given distribution of matter also should be invariant under any transformations at which the geodesic equations remain invariant. However, the geodesi...