We survey computational approaches and solutions for discovering locally dense groups in social and complex networks. A graph-theoretical property is local if it is definable over subgraphs induced by the groups only. In this context, we discuss perfectly dense groups (cliques), structurally dense groups (plexes, cores), and statistically dense groups (η-dense groups). We give algorithms (and h...

We present an automatic approach to segment an object in calibrated images acquired from multiple viewpoints. Our system starts with a new piecewise planar layer-based stereo algorithm that estimates a dense depth map that consists of a set of 3D planar surfaces. The algorithm is formulated using an energy minimization framework that combines stereo and appearance cues, where for each surface, ...

In this work we propose the method for a rather unexplored problem of computer vision discriminatively trained dense surface normal estimation from a single image. Our method combines contextual and segment-based cues and builds a regressor in a boosting framework by transforming the problem into the regression of coefficients of a local coding. We apply our method to two challenging data sets ...

Let P be a polygon with n vertices. We say that two points of P see each other if the line segment connecting them lies inside (the closure of) P . In this paper we present efficient approximation algorithms for finding the smallest set G of points of P so that each point of P is seen by at least one point of G, and the points of G are constrained to be belong to the set of vertices of an arbit...

Let A and S denote the double arrow of Alexandroff Sorgenfrey line, respectively. We show that any homeomorphism h:mA→mA is locally (outside a nowhere dense set) product monotone embeddings hi:Ji⊆A→A(i∈m) followed by permutation coordinates. also prove symmetric products Fm(A) are not homogeneous for m≥2. This partially solves an open question A. Arhangel'skiǐ [1]. In contrast, we F2(S) homogen...

We prove that any subanalytic locally Lipschitz function has the Sard property. Such functions are typically nonsmooth and their lack of regularity necessitates the choice of some generalized notion of gradient and of critical point. In our framework these notions are defined in terms of the Clarke and of the convex-stable subdifferentials. The main result of this note asserts that for any suba...

We describe a method based on the Hough transform to compute a set of parameters that completely describe line segments. By complete, we mean the description includes the endpoints of each segment as well as the number of points along the segment, and, assuming a noise model N, the parameter(s) of N. The method involves fitting a surface locally to the Hough array, where the variables of the fi...