Inverse scattering series is the only nonlinear, direct inversion method for the multidimensional, acoustic or elastic equation. Recently developed techniques for inverse problems based on the inverse scattering series [Weglein et al., Geophys., 62 (1997), pp. 1975–1989; Top. Rev. Inverse Problems, 19 (2003), pp. R27–R83] were shown to require two mappings, one associating nonperturbative descr...

The radial component of the peculiar velocities of galaxies cause displacements in their positions in redshift space. We study the effect of the peculiar velocities on the linear redshift space two point correlation function. Our analysis takes into account the radial nature of the redshift space distortions and it highlights the limitations of the plane parallel approximation. We consider the ...

In this paper, a new inversion scheme for surface-wave velocities in a slightly anisotropic medium will be presented, revisiting the inversion method performed by Corchete and Badal (2004). Tecnociencia 6(2), 23–41). An extension of the Smith–Dahlen formulation will be examined and revised. The surfacewave propagation in a slightly anisotropic medium will be considered, and the inversion of the...

The variety of perception models included in JPEG2000 are the key for its rate-distortion performance. However, the most powerful perceptual model (masking using non-linear divisive normalization) had to be simplified to make it invertible. Recently, a robust and fast algorithm to invert the exact expression of divisive normalization has been derived and successfully used in the achromatic DCT ...

The Tweedie family of distributions is a family of exponential dispersion models with power variance functions V (μ) = μp for p 6∈ (0, 1). These distributions do not generally have density functions that can be written in closed form. However, they have simple moment generating functions, so the densities can be evaluated numerically by Fourier inversion of the characteristic functions. This pa...

We study the projective space S of rational parameter representations of degree d or less in real projective space P. The parameter representations of degree less than d form a special algebraic variety K1. We investigate the subspaces on K1 and their relation to rational curves in P, give a geometric characterization of the automorphism group of K1 and outline applications of the theory to pro...

New-generation electromagnetic (EM) and sonic logging tools are capable of measuring multi-frequency multi-component data at multiple depths of investigation. This allows us to image the formation around the borehole by using an inversion method. A method is developed for directly obtaining porosity and fluid saturation distributions by simultaneously inverting borehole EM and sonic measurement...

A new method for the reconstruction of the projected mass distribution of clusters of galaxies from the image distortion of background galaxies is discussed. This method is essentially equivalent to the one we developed previously, i.e., the noise-filtering method, but has several practical advantages: (1) It is much easier to implement; (2) it can be easily applied to widefield images, since t...