We present an algorithm to generate a one-sided approximation of a given triangular mesh. We refer to such an approximate mesh as a bounding mesh, which includes the original mesh and has fewer vertices. Likewise, an inner bounding mesh is defined as an approximate mesh that is included by a given mesh. Our proposed bounding mesh algorithm performs iterative edge contractions and can generate b...

Minimum distance computations on complex geometry commonly employ hierarchies of bounding volumes that are pruned through establishment of upper and lower bounds. In this paper we describe a novel time coherence scheme which utilizes coherence on these bounds, rather than coherence derived from the geometry of the bounding volumes or from the geometry of the underlying model. This method is thu...

We show that the problem of minimizing the sum of arbitrary-norm real distances to misclassified points, from a pair of parallel bounding planes of a classification problem, divided by the margin (distance) between the two bounding planes, leads to a simple parameterless linear program. This constitutes a linear support vector machine (SVM) that simultaneously minimizes empirical error of miscl...

This thesis addresses the security of two fundamental elements of wireless networking: neighbor discovery and ranging. Neighbor discovery consists in discovering devices available for direct communication or in physical proximity. Ranging, or distance bounding, consists in measuring the distance between devices, or providing an upper bound on this distance. Both elements serve as building block...

Distance-Bounding identification protocols aim at impeding man-in-themiddle attacks by measuring response times. There are three kinds of attacks such protocols could address: (1) Mafia attacks where the adversary relays communication between honest prover and honest verifier in different sessions; (2) Terrorist attacks where the adversary gets limited active support from the prover to imperson...

We consider a long-range growth dynamics on the two-dimensional integer lattice, initialized by a finite set of occupied points. Subsequently, a site x becomes occupied if the pair consisting of the counts of occupied sites along the entire horizontal and vertical lines through x lies outside a fixed Young diagram Z. We study the extremal quantity μ(Z), the maximal finite time at which the latt...

With the advent of self-organizing systems such as ad hoc networks or pervasive computing, security protocols have to meet a new requirement for establishing trust among parties that have no a priori relationship such as a shared naming structure or a common organization. Trust establishment in this context calls for a new paradigm with respect to classical scenarios whereby entities build trus...

Many security protocols rely on the assumptions on the physical properties in which its protocol sessions will be carried out. For instance, Distance Bounding Protocols take into account the round trip time of messages and the transmission velocity to infer an upper bound of the distance between two agents. We classify such security protocols as Cyber-Physical. Time plays a key role in design a...

The continuous adoption of Near Field Communication (NFC) tags offers many new applications whose security is essential (e.g., contactless payments). In order to prevent flaws and attacks, we develop in this article a framework allowing us analyse the underlying protocols, taking into account location agents transmission delay when exchanging messages. We propose two reduction results render au...

In this paper we present a new geodesic distance transform that uses a non Euclidean metric suitable for non convex discrete 2D domains. The geodesic metric used is defined as the shortest path length through a set of pixels called Locally Nearest Hidden Pixels, and manages visibility zones using bounding angles. The algorithm is designed using ordered propagation, which makes it extremely effi...