Given a non-positively curved 2-complex with a circle-valued Morse function satisfying some extra combinatorial conditions, we describe how to locally isometrically embed this in a larger non-positively curved 2-complex with free-by-cyclic fundamental group. This embedding procedure is used to produce examples of CAT(0) free-by-cyclic groups that contain closed hyperbolic surface subgroups with...

* Corresponding author; Email: [email protected] ABSTRACT An important task in mixed-mode fracture analysis and prediction is the simulation of crack growth under mixed-mode conditions. To complete such a task, one must have (a) a computer code capable of handling the kinematics of general crack growth and determining the stress and deformation states during crack growth, and (b) a fracture crit...

Motivated to understand the behavior of biological filaments interacting with membranes of various types, we employ a theoretical model for the shape and thermodynamics of intrinsically helical filaments bound to curved membranes. We show that filament-surface interactions lead to a host of nonuniform shape equilibria, in which filaments progressively unwind from their native twist with increas...

We have investigated conformational properties of a linear semiflexible homopolymer chain in the bulk and adsorption desorption behaviour in the presence of an attractive impenetrable curved surface using lattice models. Since, it is understood that the essential physics associated with the conformational behavior of such polymer chains can be derived from a model of a self avoiding walk (SAW) ...

Surface chemistry and catalysis studies could significantly gain from the systematic variation of surface active sites, tested under the very same conditions. Curved crystals are excellent platforms to perform such systematics, which may in turn allow to better resolve fundamental properties and reveal new phenomena. This is demonstrated here for the carbon monoxide/platinum system. We curve a ...

Surface envelopes are tight, two-sided enclosures of composite spline surfaces. This paper shows how to construct the two hulls of the enclosure so that matched triangle pairs sandwich a given nonlinear, curved surface consisting of tensor-product Bézier patches. The main cost of the hull computation are 12 transversal line-plane intersections per vertex. The width of the enclosure, i,e. the di...

In this letter we propose a new Shape from Focus (SFF) method using piecewise curved search windows for accurate 3-D shape recovery. The new method uses piecewise curved windows to compute focus measure and to search for Focus Image Surface (FIS) in image space. The experimental result shows that our new method gives more accurate result than the previous SFF methods. key words: CCD camera, foc...

Embedding diagrams have been used extensively to visualize the properties of curved space in Relativity. We introduce a new kind of embedding diagram based on the extrinsic curvature (instead of the intrinsic curvature). Such an extrinsic curvature embedding diagram, when used together with the usual kind of intrinsic curvature embedding diagram, carries the information of how a surface is embe...

In the present paper, we address the problem of recovering the true underlying model of a surface while performing the segmentation. A novel criterion for surface (model) selection is introduced and its performance for selecting the underlying model of various surfaces has been tested and compared with many other existing techniques. Using this criterion, we then present a range data segmentati...