Low velocity noise can contaminate reflections and distort AVO amplitude information. I explore different inversion methods for suppressing low velocity noise while simultaneously preserving amplitudes along reflections. A velocity-stack inversion process is used for recreating models in velocity space that can reconstruct the reflections and the low velocity noise. Velocity-stack inversion is ...

Spontaneous abortion (SAb) is the most common complication of early pregnancy. Numerous risk factors are associated with an increased risk of pregnancy loss such as: Blighted ovum. The aim of this study was to determine the frequency of balanced chromosomal translocations in couples with a history of recurrent spontaneous abortions and ultrasound diagnosed blighted ovum. Sixty Eight couples wit...

In recent years Rayleigh waves have been used increasingly as a nondestructive tool to obtain near-surface S-wave velocity, one of the key parameters in environmental and engineering applications (Miller et al., 1999a, 1999b; Park et al., 1998, 1999; Xia et al., 1999, 2003; Foti et al., 2002; Beaty and Schmitt, 2003; Tian et al., 2003; Zhang and Chan, 2003; Lin and Chang, 2004; O’Neill et al., ...

In this paper, we propose an online single-pass algorithm MFC-append (Mining Frequency Change patterns in append-only data streams) for online mining frequent frequency change items in continuous append-only data streams. An online space-efficient data structure called ChangeSketch is developed for providing fast response time to compute dynamic frequency changes between data streams. A modifie...

Visual representations of ideas are valuable for creative thinking and expression. Prior research on design and informationbased ideation has assessed novelty in creative products as the inverse of the frequency that an idea or visual element occurs in the complete space of responses. In controlled experiments, frequency has previously been calculated in reference to the set of ideas collected ...

APPROACH Consider the simulated SW06 scenario with a “true” bottom consisting of 3 sediment layers (to­ taling 22m in depth extent – a medium thickness) where all three sediment layers are each defined by a linear sound-speed profile (and constant densities) all over a half-space (constant sound-speed and density) as seen in Fig. 1. For the inversion processing we shall (as in earlier work) ass...

Seismic migration/inversion is presently the most used method for determining the structure and properties of the sub-surface in seismic exploration for hydrocarbons. Determining the location of abrupt changes in medium’s parameters involves, in one form or another, an imaging principle which can simply be stated by equating a component, or the full value of the travel-time t, with zero. Depend...

Full waveform inversion (FWI) can generate high-resolution subsurface models, but often suffers from an objective function with local minima caused mainly by an absence of low frequencies in seismograms. These local minima cause cycle skipping when the initial model for FWI is far from the true model. To avoid cycle skipping, traveltime inversion is often used to compute initial models for FWI....