2,057 research outputs found

    Computationally efficient solutions for tracking people with a mobile robot: an experimental evaluation of Bayesian filters

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    Modern service robots will soon become an essential part of modern society. As they have to move and act in human environments, it is essential for them to be provided with a fast and reliable tracking system that localizes people in the neighbourhood. It is therefore important to select the most appropriate filter to estimate the position of these persons. This paper presents three efficient implementations of multisensor-human tracking based on different Bayesian estimators: Extended Kalman Filter (EKF), Unscented Kalman Filter (UKF) and Sampling Importance Resampling (SIR) particle filter. The system implemented on a mobile robot is explained, introducing the methods used to detect and estimate the position of multiple people. Then, the solutions based on the three filters are discussed in detail. Several real experiments are conducted to evaluate their performance, which is compared in terms of accuracy, robustness and execution time of the estimation. The results show that a solution based on the UKF can perform as good as particle filters and can be often a better choice when computational efficiency is a key issue

    Sol–gel-derived photonic structures handling erbium ions luminescence

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    The sol–gel technique is a very flexible, relatively simple, and low-cost method to fabricate many different innovative photonic structures characterized by specific functionalities. During synthesis, starting from the molecular level, compounds or composites with well controlled composition can be obtained as thin films, powders or monoliths. These materials can be used to prepare such structures as waveguides, photonic crystals, coatings, and bulk glasses including spheres, rings and other geometries exploited in optical resonators fabrication. This article presents some results obtained by the authors in the field of the sol–gel-derived photonic structures. To emphasise the scientific and technological interest in this kind of systems and the versatility of the sol–gel route, the glass-based nano and micrometer scale range systems are discussed. Particularly, the following systems are described: silica–hafnia glass and glass–ceramic planar waveguides, nanosized tetraphosphates, and silica colloidal crystals. The attention is focused on the spectroscopic properties of Er3+-activated materials that due to the light emission can be used in the integrated optics area covering application in sensing, biomedical diagnostic, energy conversion, telecommunication, lighting, and photon management

    Cohesin Releases DNA through Asymmetric ATPase-Driven Ring Opening

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    Cohesin stably holds together the sister chromatids from S phase until mitosis. To do so, cohesin must be protected against its cellular antagonist Wapl. Eco1 acetylates cohesin's Smc3 subunit, which locks together the sister DNAs. We used yeast genetics to dissect how Wapl drives cohesin from chromatin and identified mutants of cohesin that are impaired in ATPase activity but remarkably confer robust cohesion that bypasses the need for the cohesin protectors Eco1 in yeast and Sororin in human cells. We uncover a functional asymmetry within the heart of cohesin's highly conserved ABC-like ATPase machinery and find that both ATPase sites contribute to DNA loading, whereas DNA release is controlled specifically by one site. We propose that Smc3 acetylation locks cohesin rings around the sister chromatids by counteracting an activity associated with one of cohesin's two ATPase sites. Tight regulation of DNA entrapment and release by the cohesin complex is crucial for its multiple cellular functions. Elbatsh et al. find that cohesin's release from DNA requires an activity associated with one of its ATPase sites, whereas both sites control cohesin's loading onto DNA

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

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    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

    Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip

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    The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS

    Primary systemic sclerosis heart involvement: A systematic literature review and preliminary data-driven, consensus-based WSF/HFA definition

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    Introduction: Primary heart involvement in systemic sclerosis may cause morpho-functional and electrical cardiac abnormalities and is a common cause of death. The absence of a clear definition of primary heart involvement in systemic sclerosis limits our understanding and ability to focus on clinical research. We aimed to create an expert consensus definition for primary heart involvement in systemic sclerosis. Methods: A systematic literature review of cardiac involvement and manifestations in systemic sclerosis was conducted to inform an international and multi-disciplinary task force. In addition, the nominal group technique was used to derive a definition that was then subject to voting. A total of 16 clinical cases were evaluated to test face validity, feasibility, reliability and criterion validity of the newly created definition. Results: In total, 171 publications met eligibility criteria. Using the nominal group technique, experts added their opinion, provided statements to consider and ranked them to create the consensus definition, which received 100% agreement on face validity. A median 60(5–300) seconds was taken for the feasibility on a single case. Inter-rater agreement was moderate (mKappa (95% CI) = 0.56 (0.46–1.00) for the first round and 0.55 (0.44–1.00) for the second round) and intra-rater agreement was good (mKappa (95% CI) = 0.77 (0.47–1.00)). Criterion validity showed a 78 (73–84)% correctness versus gold standard. Conclusion: A preliminary primary heart involvement in systemic sclerosis consensus-based definition was created and partially validated, for use in future clinical research

    POREZ NA DOHODAK U REPUBLICI HRVATSKOJ

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    Ovaj članak obrađuje porez na dohodak kao neposredni (izravni) porez u poreznom sustavu Republike Hrvatske kojim su obuhvaćeni fizičke osobe, obveznici poreza na dohodak. Definiranje i pojašnjenje vrste dohodaka s obzirom na izvor dohotka i to: dohodak od nesamostalnog rada, dohodak od samostalne djelatnosti, dohodak od imovine i imovinskih prava, dohodak od kapitala, dohodak od osiguranja, drugi dohodak, te metodologija utvrđivanja porezne obveze i poreznih stopa i utvrđivanje poreznog razdoblja. Navedeni su primici koji se ne smatraju dohotkom, što je to porezni gubitak te osobni odbitak kao neoporezivi dio dohotka
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