732 research outputs found

    The correction of hadronic nucleus polarizability to hyperfine structure of light muonic atoms

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    The calculation of hadronic polarizability contribution of the nucleus to hyperfine structure of muonic hydrogen and helium is carried out within the unitary isobar model and experimental data on the polarized structure functions of deep inelastic lepton-proton and lepton-deuteron scattering. The calculation of virtual absorption cross sections of transversely and longitudinally polarized photons by nucleons in the resonance region is performed in the framework of the program MAID.Comment: 8 pages, 3 figures, Talk presented at 23th International Workshop on High Energy Physics and Quantum Field Theory (QFTHEP 2017

    Triangulations and volume form on moduli spaces of flat surfaces

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    In this paper, we are interested in flat metric structures with conical singularities on surfaces which are obtained by deforming translation surface structures. The moduli space of such flat metric structures can be viewed as some deformation of the moduli space of translation surfaces. Using geodesic triangulations, we define a volume form on this moduli space, and show that, in the well-known cases, this volume form agrees with usual ones, up to a multiplicative constant.Comment: 42 page

    Spherical averages in the space of marked lattices

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    A marked lattice is a dd-dimensional Euclidean lattice, where each lattice point is assigned a mark via a given random field on Zd{\mathbb Z}^d. We prove that, if the field is strongly mixing with a faster-than-logarithmic rate, then for every given lattice and almost every marking, large spheres become equidistributed in the space of marked lattices. A key aspect of our study is that the space of marked lattices is not a homogeneous space, but rather a non-trivial fiber bundle over such a space. As an application, we prove that the free path length in a crystal with random defects has a limiting distribution in the Boltzmann-Grad limit

    Comparison of System Call Representations for Intrusion Detection

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    Over the years, artificial neural networks have been applied successfully in many areas including IT security. Yet, neural networks can only process continuous input data. This is particularly challenging for security-related non-continuous data like system calls. This work focuses on four different options to preprocess sequences of system calls so that they can be processed by neural networks. These input options are based on one-hot encoding and learning word2vec or GloVe representations of system calls. As an additional option, we analyze if the mapping of system calls to their respective kernel modules is an adequate generalization step for (a) replacing system calls or (b) enhancing system call data with additional information regarding their context. However, when performing such preprocessing steps it is important to ensure that no relevant information is lost during the process. The overall objective of system call based intrusion detection is to categorize sequences of system calls as benign or malicious behavior. Therefore, this scenario is used to evaluate the different input options as a classification task. The results show, that each of the four different methods is a valid option when preprocessing input data, but the use of kernel modules only is not recommended because too much information is being lost during the mapping process.Comment: 12 pages, 1 figure, submitted to CISIS 201

    Accessory mineralization of dolomite reservoirs as the factor of fluids variability composition

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    © SGEM2017. All Rights Reserved. Oil-saturated Visean dolomite reservoirs were studied from the Tatarstan Republic, east of Russian platform. The main methods of study were X-ray and SEM analysis. Dolomite forms interstratified dense and porous layers with thickness of 0.5-4.0 m in oil-saturated parts of reservoirs. The dolomites are characterized by rhombic form of crystals. Many of them have crystal growth zones as alternate micro-layers with different iron content. In the pore space of dense dolomites find some iron accessory minerals such as siderite and pyrite. There are accessory crystals of quartz and aggregates of microcline in cavernous of porosity dolomites. Based on the heterogeneous composition of dolomites and their accessory minerals associations were modeled stages and hydrochemical parameters variation of fluids before oil charge

    Carbonate formation of the Lower Carboniferous in central part of Volga-Ural basin

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    Carbonate rocks of the Lower Carboniferous (Tournaisian stage) of the central Volga-Ural basin (the eastern portion of the East European platform) are of practical scientific interest to geologists, particularly because they contain large reserves of oil. Although such layers have been studied, various questions pertaining to development of sedimentation schemes for the rocks have not been answered. We have attempted to resolve these by studying a wealth of drill core materials. The study involved structural and genetic analysis of rocks and facies reconstructions. The rocks are mainly represented by different types of shallowwater limestone. The thickness of coeval layers and their lithological structures changes from well to well within an oilfield, primarily due to the different environments of sedimentation during the Tournaisian stage. Therefore, to identify the characteristics of carbonate sedimentation, we have studied the sequences of different types of limestone and analysed their thickness. As a result, we have developed principle schemes of sedimentation for shallow-water carbonate rocks of the Tournaisian stage. This may help in the predictive search for reservoir rocks in the region of study

    Square-tiled cyclic covers

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    A cyclic cover of the complex projective line branched at four appropriate points has a natural structure of a square-tiled surface. We describe the combinatorics of such a square-tiled surface, the geometry of the corresponding Teichm\"uller curve, and compute the Lyapunov exponents of the determinant bundle over the Teichm\"uller curve with respect to the geodesic flow. This paper includes a new example (announced by G. Forni and C. Matheus in \cite{Forni:Matheus}) of a Teichm\"uller curve of a square-tiled cyclic cover in a stratum of Abelian differentials in genus four with a maximally degenerate Kontsevich--Zorich spectrum (the only known example found previously by Forni in genus three also corresponds to a square-tiled cyclic cover \cite{ForniSurvey}). We present several new examples of Teichm\"uller curves in strata of holomorphic and meromorphic quadratic differentials with maximally degenerate Kontsevich--Zorich spectrum. Presumably, these examples cover all possible Teichm\"uller curves with maximally degenerate spectrum. We prove that this is indeed the case within the class of square-tiled cyclic covers.Comment: 34 pages, 6 figures. Final version incorporating referees comments. In particular, a gap in the previous version was corrected. This file uses the journal's class file (jmd.cls), so that it is very similar to published versio

    Diagenetic dolomite reservoirs in carboniferous rocks of Melekess depression and South-Tatar arch

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    It was studied secondary dolomite reservoirs in Carboniferous oil saturated carbonate rocks from the Melekess depression and South-Tatar arch. It was revealed three morphological types of non-anticlinal dolomite traps: lenticular, one-layer, multilayer. It was found that the development of lenticular dolomite traps confined to zones of oilwater contacts, one-layer to flanks of anticlinal uplifts which connected with the migration ways of oil-water fluids (tectonic faults, erosion incisions). It was suggested the mechanism of formation dolomite reservoir due to the oxidation of hydrocarbons and upward migration of carbon dioxide deep fluids
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