6,957 research outputs found
Addendum: Neutrino Mass Hierarchy Determination Using Reactor Antineutrinos
No full textWe update our study of neutrino mass hierarchy determination using a high statistics reactor ν̄ e experiment in the light of the recent evidences of a relatively large non-zero value of θ 13 from the Daya Bay and RENO experiments. We find that there are noticeable modifications in the results, which allow a relaxation in the detector's characteristics, such as the energy resolution and exposure, required to obtain a significant sensitivity to, or to determine, the neutrino mass hierarchy in such a reactor experiment. © SISSA 2012
On boundary behavior by prime ends of solutions to Beltrami equations
No full textPetkov I. On boundary behavior by prime ends of solutions to Beltrami equations / I. Petkov, V. Ryazanov // Algebraic and geometric methods of analysis – 2020 : book of abstr. the Intern. sci. conf., Odessa, 26–30 May 2020 / [Odesa Nat. Acad. of Food Technologies et al.]; аdministrative comm.: B. Egorov (chairman) et al. – Odessa, 2020. – P. 50. – Ref.: 3 tit
Predicting the values of the leptonic CP violation phases in theories with discrete flavour symmetries
No full textAbstractUsing the fact that the neutrino mixing matrix U=Ue†Uν, where Ue and Uν result from the diagonalisation of the charged lepton and neutrino mass matrices, we consider a number of forms of Uν associated with a variety of discrete symmetries: i) bimaximal (BM) and ii) tri-bimaximal (TBM) forms, the forms corresponding iii) to the conservation of the lepton charge L′=Le−Lμ−Lτ (LC), iv) to golden ratio type A (GRA) mixing, v) to golden ratio type B (GRB) mixing, and vi) to hexagonal (HG) mixing. Employing the minimal form of Ue, in terms of angles and phases it contains, that can provide the requisite corrections to Uν so that reactor, atmospheric and solar neutrino mixing angles θ13, θ23 and θ12 have values compatible with the current data, including a possible sizable deviation of θ23 from π/4, we discuss the possibility to obtain predictions for the CP violation phases in the neutrino mixing matrix. Considering the “standard ordering” of the 12 and the 23 rotations in Ue and following the approach developed in [1] we derive predictions for the Dirac phase δ and the rephasing invariant JCP in the cases of GRA, GRB and HG forms of Uν (results for the TBM and BM (LC) forms were obtained in [1]). We show also that under rather general conditions within the scheme considered the values of the Majorana phases in the PMNS matrix can be predicted for each of the forms of Uν discussed. We give examples of these predictions and of their implications for neutrinoless double beta decay. In the GRA, GRB and HG cases, as in the TBM one, relatively large CP violation effects in neutrino oscillations are predicted (|JCP|∼(0.031–0.034)). Distinguishing between the TBM, BM (LC), GRA, GRB and HG forms of Uν requires a measurement of cosδ or a relatively high precision measurement of JCP
On the asymptotic behavior of solutions to nonlinear Beltrami equation
No full textPetkov I. On the asymptotic behavior of solutions to nonlinear Beltrami equation / I. Petkov, R. Salimov, M. Stefanchuk // Algebraic and geometric methods of analysis - 2024 : abstr. of the Intern. sci. conf., Odesa, 27-30 May - 2024 / [Odesa Nat. Univ. of Technology et al.] ; sci comm.: [ Yu. Fedchenko, N. Konovenko et al.]. – Odesa, 2024. – P. 118–119. – Ref.: 1 tit
A push-pull CORF model of a simple cell with antiphase inhibition improves SNR and contour detection.
No full textWe propose a computational model of a simple cell with push-pull inhibition, a property that is observed in many real simple cells. It is based on an existing model called Combination of Receptive Fields or CORF for brevity. A CORF model uses as afferent inputs the responses of model LGN cells with appropriately aligned center-surround receptive fields, and combines their output with a weighted geometric mean. The output of the proposed model simple cell with push-pull inhibition, which we call push-pull CORF, is computed as the response of a CORF model cell that is selective for a stimulus with preferred orientation and preferred contrast minus a fraction of the response of a CORF model cell that responds to the same stimulus but of opposite contrast. We demonstrate that the proposed push-pull CORF model improves signal-to-noise ratio (SNR) and achieves further properties that are observed in real simple cells, namely separability of spatial frequency and orientation as well as contrast-dependent changes in spatial frequency tuning. We also demonstrate the effectiveness of the proposed push-pull CORF model in contour detection, which is believed to be the primary biological role of simple cells. We use the RuG (40 images) and Berkeley (500 images) benchmark data sets of images with natural scenes and show that the proposed model outperforms, with very high statistical significance, the basic CORF model without inhibition, Gabor-based models with isotropic surround inhibition, and the Canny edge detector. The push-pull CORF model that we propose is a contribution to a better understanding of how visual information is processed in the brain as it provides the ability to reproduce a wider range of properties exhibited by real simple cells. As a result of push-pull inhibition a CORF model exhibits an improved SNR, which is the reason for a more effective contour detection
Safety in Numbers: A strategy for cycling?
No full textJennifer Bonham, Stuart Cathcart, John Petkov and Peter Lum
Reduced Inverse Distance Weighting Interpolation for Painterly Rendering
No full textThe interpolation problem of irregularly distributed data, in a multidimensional domain is considered. A modification of the inverse distance weighting interpolation formula. is proposed; making computation time independent of the number of data, points. Only the first K neighbors of a given point are considered, instead of the entire dataset. Additional factors are introduced, preventing discontinuities on points where tire set; of local neighbors charges. Theoretical analysis provides conditions which guarantee continuity. The proposed approach is efficient and free front magic numbers. Unlike many existing algorithms based on the k-nearest neighbors the number of neighbors is derived from theoretical principles. The method has been applied to the problem of vector field generation in the context of artistic imaging. Experimental results show its ability to produce brush strokes oriented along object contours and to effectively render meaningful texture details.</p
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