Several structures are built on collapsible soils in the mining and petroleum industries civil sites. In order to analyze stability of such structures, one must properly study unsaturated soil behavior. Collapsible frequent sand that susceptible a significant sudden reduction volume upon wetting. An important factor is matric suction, which es related moisture content through water Characterist...

Collapsible soils are unsaturated low-density that undergo abrupt settlement when flooded without any increase in the in-situ stress level. The first stage of site characterization is identifying collapsible soils, since these problematic soils. Seismic cone testing (SCPT) has been increasingly used for characterization, because it allows combining stratigraphic logging with maximum shear modul...

We study (collapsible) higher-order pushdown systems — theoretically robust and wellstudied models of higher-order programs — along with their natural subclass called (collapsible) higher-order basic process algebras. We provide a comprehensive analysis of the model checking complexity of a range of both branching-time and linear-time temporal logics. We obtain tight bounds on data, expression,...

We construct the first explicit example of a simplicial 3-ball B15,66 that is not collapsible. It has only 15 vertices. We exhibit a second 3-ball B12,38 with 12 vertices that is collapsible and not shellable, but evasive. Finally, we present the first explicit triangulation of a 3-sphere S18,125 (with only 18 vertices) that is not locally constructible. All these examples are based on knotted ...

Let A be an idempotent algebra on a 3-element domain D that omits a G-set for a factor. Suppose A is not αβ-projective (for some α, β ⊂ D so that α ∪ β = D and α ∩ β 6= ∅) and is not collapsible. It follows that A is switchable. We prove that, for every finite subset ∆ of Inv(A), Pol(∆) is collapsible. We also exhibit an algebra that is collapsible from a non-singleton source but is not collaps...