An experimental study of four variants of pose clustering from dense range data

Parameter clustering is a robust estimation technique based on location statistics in a parameter space where parameter samples are computed from data samples. This article investigates parameter clustering as a global estimator of object pose or rigid motion from dense range data without knowing correspondences between data points. Four variants of the algorithm are quantitatively compared regarding estimation accuracy and robustness: sampling poses from data points or from points with surface normals derived from them, each combined with clustering poses in the canonical or consistent parameter space, as defined in Hillenbrand (2007). An extensive test data set is employed: synthetic data generated from a public database of three-dimensional object models through various levels of corruption of their geometric representation; real range data from a public database of models and cluttered scenes. It turns out that sampling raw data points and clustering in the consistent parameter space yields the estimator most robust to data corruption. For data of sufficient quality, however, sampling points with normals is more efficient; this is most evident when detecting objects in cluttered scenes. Moreover, the consistent parameter space is always preferable to the canonical parameter space for clustering

Inhibition of return is no hallmark of exogenous capture by unconscious cues

Inhibition of irrelevant information and response tendencies is a central characteristic of conscious control and executive functions. However, recent theories in vision considered Inhibition of Return (IOR: slower responses to attended than unattended positions) to be a hallmark of automatic exogenous capture of visual attention by unconscious cues. In the present study, we show that an unconscious cue that exogenously captures attention does not lead to IOR. First of all, subliminal cues with a contrast different from a searched-for target contrast capture attention independently of their match of contrast polarity to the search criteria. This is found with a short cue-target interval (Exp. 1). However, the same cues do not lead to IOR with a long cue-target interval. The lack of IOR is also verified for several intermediate intervals (Exp. 2), for high-contrast cues and low-contrast targets (Exp. 3), and with lower luminance cues presented on a CRT screen (Exp. 4). Finally, no capture effect but IOR is found for consciously perceived anti-predictive cues (Exp. 5). Together the results support the notion of a double dissociation between IOR and exogenous capture and are in line with a decisive role of consciousness for inhibition

Twisted K-theory and obstructions against positive scalar curvature metrics

We decompose the twisted index obstruction $\theta(M)$ against positive scalar curvature metrics for oriented manifolds with spin universal cover into a pairing of a twisted $K$-homology with a twisted $K$-theory class and prove that $\theta(M)$ does not vanish if $M$ is an orientable enlargeable manifold with spin universal cover.Comment: 21 pages (drastically streamlined with focus on the proof of the non-vanishing result

Note on maximal split-stable subgraphs

A multigraph G=(V,R∪B) with red and blue edges is an R/B-split graph if V is the union of a red and a blue stable set. Gavril has shown that R/B-split graphs yield a common generalization of split graphs and König–Egerváry graphs. Moreover, R/B-split graphs can be recognized in linear time. In this note, we address the corresponding optimization problem: identify a set of vertices of maximal cardinality that decomposes into a red and a blue stable set. This problem is NP-hard in general. We investigate the complexity of special and related cases (e.g., (anti-)chains in partial orders and stable matroid bases) and exhibit some NP-hard cases as well as polynomial ones

On the number of simple cycles in planar graphs

Let CG denote the number of simple cycles of a graph G and let Cn be the maximum of CG over all planar graphs with n nodes We present a lower bound on Cn constructing graphs with at least n cycles Applying some probabilistic arguments we prove an upper bound of n We also discuss this question restricted to the subclasses of grid graphs bipartite graphs and of colorable triangulated graph

Программные решения организации работы с ЭМК на мобильных устройствах в off-line режиме

The article deals with software solutions for e-health card under the access to the services of a medical information system. Consideration of some cross-platform solution for e-health card, as well as highlights the main approaches to the development of this service

Torsion-freeness and non-singularity over right p.p.-rings

AbstractA right R-module M is non-singular if xI≠0 for all non-zero x∈M and all essential right ideals I of R. The module M is torsion-free if Tor1R(M,R/Rr)=0 for all r∈R. This paper shows that, for a ring R, the classes of torsion-free and non-singular right R-modules coincide if and only if R is a right Utumi-p.p.-ring with no infinite set of orthogonal idempotents. Several examples and applications of this result are presented. Special emphasis is given to the case where the maximal right ring of quotients of R is a perfect left localization of R

The sustainability of the agrifood system: determinants of the interaction between global and local agrifood governance

"The sustainability of today’s global agrifood system is shaped by a complex web of global and local forces. These forces include local values and practices, transnational corporations (TNCs), agricultural policies and politics of the EU as well as the activities of the United Nations Development Program, for instance. This paper aims to develop a framework for analyzing the interaction of various global and local forces in shaping the agrifood system and its sustainability characteristics. This framework allows the systematic and comprehensive identification of the relative impact of global versus local, material versus normative, and actor-specific versus structural forces. In a second step, the paper illustrates the framework’s reach in an investigation of determinants of policies and practices regarding genetically modified organisms (GMOs) in India. GMO practices and policies represent a contested ground where local and “international” values and interests frequently clash. In consequence, the commercial introduction of GMOs in India presents an excellent case study for the interaction of forces in the agrifood system." [author's abstract