141 research outputs found

    Motivic Milnor fibre for nondegenerate function germs on toric singularities

    Full text link
    We study function germs on toric varieties which are nondegenerate for their Newton diagram. We express their motivic Milnor fibre in terms of their Newton diagram. We extend a formula for the motivic nearby fibre to the case of a toroidal degeneration. We illustrate this by some examples.Comment: 14 page

    Ensuring the effectiveness of the taxi order service by mathematical modeling of its work

    Get PDF
    We can’t imagine modern science without mathematical modeling. At the same time, ideas related to mathematical modeling find themselves in various fields. One of the interesting applications of mathematical modeling of random processes is the work of the taxi order service. The article describes the description of the operation of the taxi order service using autoregressive models with multiple roots of characteristic equations of different multiplicity. Also attempts were made to approximate and predict the time series of various important parameters of the taxi order service. Algorithms for identifying model parameters are proposed.The study was supported by RFBR, project No 17-01-00179

    Development of software system for analysis and optimization of taxi services efficiency by statistical modeling methods

    Get PDF
    In the present work it is suggested to use statistical models for taxi service data analysis and forecasting. Special attention is paid to the application of methods of model parameters identification and short-term forecasts making. We suggest to use the mathematical models of images to account the alternating character, associated with the dependence of the number of taxi orders from various parameters. In addition the possibility of improving the effectiveness of evaluation through the use of mixed models of random fields is shown.This work was supported by the OOO "EIS-PFO" (Ulyanosk, Russia). We express our special gratitude for provided information used in the research

    Chronic non-specific back pain: patho-genetic substantiation of manual therapy

    Get PDF
    We presented the review of data from MEDLINE, EMBASE, CINAHL on the mechanisms of therapeutic activity of manual therapy, as well as on studied tissue and systemic responses, and the elaborations on the issue of manual treatment choice in chronic non-specific back pain.</p

    Rotavirus infection in children: clinical and laboratory features and catamnesis

    Get PDF
    Purpose is to study the clinical, laboratory and instrumental characteristics of the course of rotavirus infection in children up to 3 years in the acute phase and during the convalescence period. Material and methods. A clinical, laboratory and instrumental examination of 320 children up to 3 years with moderate to severe rotavirus infection. Results. The presence of long-term persistence of rotavirus recovering from rotavirus infection. Identified functional disorders of the digestive system in the acute period and the period of convalescence in children up to 3 years with rotavirus infection. Conclusion. For a long period (up to 3 months), almost half of patients may experience intestinal dysfunction, possibly related to the long-term persistence of rotavirus

    Output spectrum of a detector measuring quantum oscillations

    Full text link
    We consider a two-level quantum system (qubit) which is continuously measured by a detector and calculate the spectral density of the detector output. In the weakly coupled case the spectrum exhibits a moderate peak at the frequency of quantum oscillations and a Lorentzian-shape increase of the detector noise at low frequency. With increasing coupling the spectrum transforms into a single Lorentzian corresponding to random jumps between two states. We prove that the Bayesian formalism for the selective evolution of the density matrix gives the same spectrum as the conventional master equation approach, despite the significant difference in interpretation. The effects of the detector nonideality and the finite-temperature environment are also discussed.Comment: 8 pages, 6 figure

    Selective quantum evolution of a qubit state due to continuous measurement

    Full text link
    We consider a two-level quantum system (qubit) which is continuously measured by a detector. The information provided by the detector is taken into account to describe the evolution during a particular realization of measurement process. We discuss the Bayesian formalism for such ``selective'' evolution of an individual qubit and apply it to several solid-state setups. In particular, we show how to suppress the qubit decoherence using continuous measurement and the feedback loop.Comment: 15 pages (including 9 figures

    Alpha-cluster Condensations in Nuclei and Experimental Approaches for their Studies

    Full text link
    The formation of alpha-clusters in nuclei close to the decay thresholds is discussed. These states can be considered to be boson-condensates, which are formed in a second order phase transition in a mixture of nucleons and alpha-particles. The de Broglie wavelength of the alpha-particles is larger than the nuclear diameter, therefore the coherent properties of the alpha-particles give particular effects for the study of such states. The states are above the thresholds thus the enhanced emission of multiple-alphas into the same direction is observed. The probability for the emission of multiple-alphas is not described by Hauser-Feshbach theory for compound nucleus decay.Comment: 21 pages, 12 figures

    Study of KS KL Coupled Decays and KL -Be Interactions with the CMD-2 Detector at VEPP-2M Collider

    Full text link
    The integrated luminosity about 4000 inverse nanobarn of around phi meson mass ( 5 millions of phi mesons) has been collected with the CMD-2 detector at the VEPP-2M collider. A latest analysis of the KS KL coupled decays based on 30 % of available data is presented in this paper. The KS KL pairs from phi meson decays were reconstructed in the drift chamber when both kaons decayed into two charged particles. From a sample of 1423 coupled decays a selection of candidates to the CP violating KL into pi+ pi- decay was performed. CP violating decays were not identified because of the domination of events with a KL regenerating at the Be beam pipe into KS and a background from KL semileptonic decays. The regeneration cross section of 110 MeV/c KL mesons was found to be 53 +- 17 mb in agreement with theoretical expectations. The angular distribution of KS mesons after regeneration and the total cross section of KL for Be have been measured.Comment: 14 pages, 8 figure

    Search for lepton-flavor violation at HERA

    Get PDF
    A search for lepton-flavor-violating interactions epμXe p \to \mu X and epτXe p\to \tau X has been performed with the ZEUS detector using the entire HERA I data sample, corresponding to an integrated luminosity of 130 pb^{-1}. The data were taken at center-of-mass energies, s\sqrt{s}, of 300 and 318 GeV. No evidence of lepton-flavor violation was found, and constraints were derived on leptoquarks (LQs) that could mediate such interactions. For LQ masses below s\sqrt{s}, limits were set on λeq1βq\lambda_{eq_1} \sqrt{\beta_{\ell q}}, where λeq1\lambda_{eq_1} is the coupling of the LQ to an electron and a first-generation quark q1q_1, and βq\beta_{\ell q} is the branching ratio of the LQ to the final-state lepton \ell (μ\mu or τ\tau) and a quark qq. For LQ masses much larger than s\sqrt{s}, limits were set on the four-fermion interaction term λeqαλqβ/MLQ2\lambda_{e q_\alpha} \lambda_{\ell q_\beta} / M_{\mathrm{LQ}}^2 for LQs that couple to an electron and a quark qαq_\alpha and to a lepton \ell and a quark qβq_\beta, where α\alpha and β\beta are quark generation indices. Some of the limits are also applicable to lepton-flavor-violating processes mediated by squarks in RR-Parity-violating supersymmetric models. In some cases, especially when a higher-generation quark is involved and for the process epτXe p\to \tau X , the ZEUS limits are the most stringent to date.Comment: 37 pages, 10 figures, Accepted by EPJC. References and 1 figure (Fig. 6) adde
    corecore