Vol. 52 No. 1 (245) (2018)

Mathematics

  • Mathematics

    A BOUNDARY FOR THE EXISTENCE OF SOLUTION TO THE MAXIMUM ENTROPY PROBLEM APPLIED IN EUROPEAN CALL OPTIONS

    N.D. Margaryan
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    Abstract

    The following paper introduces a computationally effective way of finding and utilizing maximum entropy problem boundaries for up to three dimensional cases. The application of the results is concentrated on financial options pricing and reverse distribution calculation. Based on market information in form of current option prices a distribution of future states is constructed. Using the suggested approach it will be possible to identify cases, where no solution to the maximum entropy problem exists, and parameters, for which a feasible solution can be reached.

    References
  • Mathematics

    ON THE MINIMAL COSET COVERINGS OF THE SET OF SINGULAR AND OF THE SET OF NONSINGULAR MATRICES

    A.V. Minasyan
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    Abstract

    It is determined minimum number of cosets over linear subspaces in $ \mathbb{F}_q $ necessary to cover following two sets of $ A (n \mathclose{\times} n) $ matrices. For one of the set of matrices $ \det{A} = 0 $ and for the other set $ \det{A} \neq 0 $. It is proved that for singular matrices this number is equal to $ 1 \mathclose{+} q \mathclose{+} q^2 \mathclose{+} \ldots \mathclose{+} q^{n-1} $ and for the nonsingular matrices it is equal to $ (q^n \mathclose{-} 1)(q^n \mathclose{-} q)(q^n \mathclose{-} q^2) \cdots (q^n \mathclose{-} q^{n-1}) / q^{\large{\binom{n}{2}}} $.

    References
  • Mathematics

    ON CONVERGENCE OF THE FOURIER DOUBLE SERIES WITH RESPECT TO THE VILENKIN SYSTEMS

    L.S. Simonyan
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    Abstract

    Let $ \{ W_k (x) \} _{k = 0}^{\infty} $ be either unbounded or bounded Vilenkin system. Then, for each $ 0 < \varepsilon < 1 $, there exist a measurable set $ E \subset [0,1)^2 $ of measure $ |E| > 1 \mathclose{-} \varepsilon $, and a subset of natural numbers $ \Gamma $ of density 1 such that for any function $ f(x,y) \in L^1 (E) $ there exists a function $ g(x,y) \in L^1 [0,1)^2 $, satisfying the following conditions: $ g(x, y) = f(x,y) $ on $ E \ ; $ the nonzero members of the sequence $ \{ |c_{k, s}(g)| \} $ are monotonically decreasing in all rays, where $ c_{k, s} (g) = \int\limits_{0}^{1} \int\limits_{0}^{1} g(x, y) \overline{W_k}(x) \overline{W_s}(y) dx dy \ ; $ $ \lim\limits_{R \in \Gamma,\ R \to \infty} S_R((x,y),g) = g(x,y) $ almost everywhere on $ [0,1)^2 $, where $ S_R((x,y),g) = \sum\limits_{k^2+s^2 \leq R^2} c_{k, s}(g) W_k(x) W_s(y) $.

    References
  • Mathematics

    ON AN INTEGRO-DIFFERENTIAL EQUATION OF PSEUDOPARABOLIC-PSEUDOHYPERBOLIC TYPE WITH DEGENERATE KERNELS

    T.K. Yuldashev
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    Abstract

    In the article the questions of solvability of boundary value problem for a homogeneous pseudoparabolic-pseudohyperbolic type integro-differential equation with degenerate kernels are considered. The Fourier method based on separation of variables is used. A criterion for the one-valued solvability of the considering problem is found. Under this criterion the one-valued solvability of the problem is proved.

    References

Mechanics

  • Mechanics

    LOCALIZED BENDING VIBRATIONS OF PIEZOCERAMIC TRANSVERSE POLARIZED PLATE

    M.V. Belubekyan, S.V. Sargsyan, A.A. Papyan
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    Abstract

    Problem of the piezoceramic plate polarized along the normal of the middle plane of the plate is solved, based on the assumptions of the hypothesis of Kirchhoff, taking into account the components characterizing the electric field. The equations of planar and bending vibrations are obtained. Localized bending vibrations are considered, and the effect of the electric field on the frequency of localized vibrations is investigated.

    References

Informatics

Physics

  • Physics

    INFLUENCE OF NANOPARTICLES OF $ \mathrm{CuO} $ ON THE STABILITY AND CONDUCTIVITY OF BLM

    A.L. Torosyan, G.V. Ananyan, V.B. Arakelyan
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    Abstract

    This study aims to provide arguments for an increase in the stability of bilayer lipid membranes (BLM) in an electrical field in presence of $ \mathrm{CuO} $ nanoparticles. Moreover, the sustainability of BLM becomes more stable with increasing of nanoparticles concentration. It is shown that an increase in the stability of BLM in an electrical field is mainly due to an increase in the coefficient of linear tension of the edge of a pore, which is forming in BLM. It is shown as well, that the presence of nanoparticles of $ \mathrm{CuO} $ in the solution surrounding BLM leads to a decrease in the conductivity of the BLM.

    References
  • Physics

    STRAIGHT CALCULATION OF HELIX–COIL TRANSITION PARAMETERS IN HETEROPOLYMERS

    A.V. Asatryan, A.K. Andriasyan, A.A. Hakobyan, Sh.A. Tonoyan, Ye.Sh. Mamasakhlisov, V.F. Morozov
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    Abstract

    The main goal of this paper is the investigation of helix–coil transition in heteropolymers by means of straight calculation of partition function, free energy, helicity degree and other characteristics of transition on the bases of generalized model of polypeptide chain. Product of random matrices was applied to solve the problem for the comparison with constrained annealing method in the future.

    References
  • Physics

    FORMATION OF THE DISCLINATION DEFECTS IN THE DYE-DOPED CHOLESTERIC LIQUID CRYSTALLINE STRUCTURE UNDER THE INFLUENCE OF THE LASER BEAM

    Zh.V. Ninoyan
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    Abstract

    In the work the influence of the laser beam on the optical properties of highly absorbing dye-doped cholesteric liquid crystalline (CLC) structure is investigated. By means of polarizing microscope studies step-like variation of the CLC helical pitch and formation of the disclination defect lines (oily streaks) is observed.

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Short Communications

  • Short Communications

    ON AUTOMORPHISMS AND ENDOMORPHISMS OF CC GROUPS

    H.T. Aslanyan
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    Abstract

    We consider the automorphisms description question for the semigroups End($G$) of a group $G$ having only cyclic centralizers (CC) of nontrivial elements. In particular, we prove that each member of the automorphism group Aut($G$) of a group $G$ from this class is uniquely determined by its action on the elements from the subgroup of inner automorphisms Inn($G$). Note that, typical examples of CC groups are absolutely free groups, free periodic groups of large enough odd periods, $n$-periodic and free products of CC groups.

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  • Short Communications

    SPP REAL-TIME AND DAY-AHEAD ENERGY MARKETS

    T.V. Piliposyan
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    Abstract

    Southwest Power Pool (SPP) is a regional power transmission organization in the United States. Virtual transactions on the SPP markets are sold at auction. There are Real-Time (RT) and Day-Ahead (DA) markets, where you can buy electricity by winning an auction. Virtual transactions are a valuable component of the bilateral market. All market participants have DA and RT series of prices in hourly basis. In this article, we take a large amount of data of DA and RT prices and try to see which distribution function have the returns of RT prices. Then we make a regression between DA and RT prices, to see how they are related to each other.

    References