A transient poroelastic formulation based on the Biot consolidation theory is presented to study the impact of underground longwall mining of coal on strata deformation and the subsequent modification of hydrogeological properties. A finite-element model is used where the geometric conditions may be complex. The important parameters in this model are identified as pore pressure ratio, ct 1 and ...

We extend Igusa ́s stationary phase method to the case of oscillatory integrals depending on several parameters. As a particular case, we obtain estimations for the modulus of Gaussian exponential sums depending on several parameters.

The idea of single difference sequence spaces was introduced by Kizmaz and this concept was generalized by various authors. In this paper, we define the sequence spaces χ2 (∆u,Mmn, p, s) and Λ2 (∆ γ u,Mmn, p, s) , where M = (Mmn) is a sequence of modulus functions, and examine some inclusion relations and properties of these spaces. 2000 Mathematics Subject Classification: 40A05,40C05,40D05.

In this article we introduce the difference sequence spacesW0[ f ,∆m],W1[ f ,∆m], W∞[ f ,∆m] and S[ f ,∆m], defined by a modulus function f . We obtain a relation between W1[ f ,∆m]∩ l∞[ f ,∆m] and S[ f ,∆m]∩ l∞[ f ,∆m] and prove some inclusion results.

A joint inversion method is developed to estimate the elastic constants of two elastic, homogeneous, isotropic media separated by a flat horizontal boundary. The method jointly uses P and S-converted wave reflection amplitude-versusangle (AVA) data and seeks the Poisson’s ratios of each layer, ratios of the densities and bulk modulus of the layers. The generalized linear inversion (GLI) method ...