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

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

Installing, Running and Maintaining Large Linux Clusters at CERN

Having built up Linux clusters to more than 1000 nodes over the past five years, we already have practical experience confronting some of the LHC scale computing challenges: scalability, automation, hardware diversity, security, and rolling OS upgrades. This paper describes the tools and processes we have implemented, working in close collaboration with the EDG project [1], especially with the WP4 subtask, to improve the manageability of our clusters, in particular in the areas of system installation, configuration, and monitoring. In addition to the purely technical issues, providing shared interactive and batch services which can adapt to meet the diverse and changing requirements of our users is a significant challenge. We describe the developments and tuning that we have introduced on our LSF based systems to maximise both responsiveness to users and overall system utilisation. Finally, this paper will describe the problems we are facing in enlarging our heterogeneous Linux clusters, the progress we have made in dealing with the current issues and the steps we are taking to gridify the clustersComment: 5 pages, Proceedings for the CHEP 2003 conference, La Jolla, California, March 24 - 28, 200

Computational methods for exploring the dynamics of cancer : the potential of state variables for description of complex biological systems

Observing dynamic patterns in silico and comparing them to experimental data in vitro or in vivo could help us identify and quantify dynamic processes. Since modellers are faced with a high degree of complexity of biological systems, appropriate concepts of system descriptions are needed. The use of state variables is expected to make models applicable to a wider range of the dynamics of biological systems. This is demonstrated by the Multi-Hit-Repair (MHR-)model which is based on a transient dose equivalent. The model calculates the survival of cells irradiated by ionizing radiation and it describes correctly a large variety of radio-biological observations. In addition, the MHR-model is bridging the gap between processes at the molecular or cellular level and tissue dynamics