Results 11 to 20 of about 298,615 (267)
Approximate solution of the representability problem [PDF]
International Journal of Quantum Chemistry, 2001 AbstractApproximate solution of the ensemble representability problem for density operators of arbitrary order is obtained. This solution is closely related to the “Q condition” of A. J. Coleman. The representability conditions are formulated in orbital representation and are easy to use.
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On a two-dimensional solvable system of difference equations
Electronic Journal of Qualitative Theory of Differential Equations, 2018 Here we solve the following system of difference equations $$x_{n+1}=\frac{y_ny_{n-2}}{bx_{n-1}+ay_{n-2}},\quad y_{n+1}=\frac{x_nx_{n-2}}{dy_{n-1}+cx_{n-2}},\quad n\in\mathbb{N}_0,$$ where parameters $a, b, c, d$ and initial values $x_{-j},$ $y_{-j}$, $j=
Stevo Stevic
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Representation of solutions to Helmholtz’s equation [PDF]
Journal of Mathematical Physics, 1984 It is proved that any potential of a single layer v is identically equal to a potential of a double layer w in the bounded domain, 𝒟, and a necessary and sufficient condition for v≡w in Ω=R3/𝒟, the exterior domain, is given.
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The representation of periodic solutions of newtonian systems
Mathematical and Computer Modelling, 2005 A method is devised to represent the periodic solutions of the differential equation x = f(x), with f(x) analytical in the neighborhood of a stable equilibrium point. The results are applied to Jacobian elliptic functions and the rate of convergence of this representation is compared with that one of other known developments of Jacobi's functions.
PAVANI, RAFFAELLA, R. Talamo
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Integral representation of solutions to Dirac systems [PDF]
Opuscula MathematicaWe introduce a novel integral form for a fundamental set of solutions to one-dimensional Dirac systems with an integrable potential and spectral parameter \(\mu \in \mathbb{C}\).
Łukasz Rzepnicki
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Asymptotic Representation of the Solutions of Linear Volterra Difference Equations
Advances in Difference Equations, 2008 This article analyses the asymptotic behaviour of solutions of linear Volterra difference equations. Some sufficient conditions are presented under which the solutions to a general linear equation converge to limits, which are given by a limit formula ...
Győri István +1 more
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A genetic algorithm for composing music [PDF]
Yugoslav Journal of Operations Research, 2010 In this paper, a genetic algorithm for making music compositions is presented. Position based representation of rhythm and relative representation of pitches, based on measuring relation from starting pitch, allow for a flexible and robust way for ...
Matić Dragan
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Representation of solutions of difference equations with continuous time
Electronic Journal of Qualitative Theory of Differential Equations, 2000 This paper describes a representation of solutions of the system of nonautonomous functional equations $x(t)=A(t)x(t-1)+B(t)x(p(t))$, in form of series, using the Cauchy matrix of the linear system $y(t)=A(t)y(t-1)$.
Hajnalka Péics
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Probabilistic representations of solutions to the heat equation [PDF]
Proceedings Mathematical Sciences, 2003 12 ...
Rajeev, B., Thangavelu, S.
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A Vectorization Approach to Solving and Controlling Fractional Delay Differential Sylvester Systems
MathematicsThis paper addresses the solvability and controllability of fractional delay differential Sylvester matrix equations with non-permutable coefficient matrices.
Fatemah Mofarreh, Ahmed M. Elshenhab
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