Results 21 to 30 of about 920,770 (191)
Қарағанды университетінің хабаршысы. Математика сериясы, 2020 A semi-periodic initial boundary-value problem for a fourth-order system of partial differential equations is considered. Using the method of functional parametrization, an additional parameter is carried out and the studied problem is reduced to the ...
A.T. Assanova, Zh.S. Tokmurzin
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Functional renormalization group for non-equilibrium quantum many-body problems [PDF]
, 2006 We extend the concept of the functional renormalization for quantum many-body problems to non-equilibrium situations. Using a suitable generating functional based on the Keldysh approach, we derive a system of coupled differential equations for the $m ...
A. C. Hewson +15 more
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On extension of solutions of a simultaneous system of iterative functional equations [PDF]
Opuscula Mathematica, 2009 Some sufficient conditions which allow to extend every local solution of a simultaneous system of equations in a single variable of the form \[ \varphi(x) = h (x, \varphi[f_1(x)],\ldots,\varphi[f_m(x)]),\] \[\varphi(x) = H (x, \varphi[F_1(x)],\ldots ...
Janusz Matkowski
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Thermodynamic Bethe Ansatz and Threefold Triangulations [PDF]
, 1995 In the Thermodynamic Bethe Ansatz approach to 2D integrable, ADE-related quantum field theories one derives a set of algebraic functional equations (a Y-system) which play a prominent role.
Gliozzi, F., Tateo, R.
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Arbitrary Choice of Basic Variables in Density Functional Theory. I. Formalism [PDF]
, 2003 The Hohenberg-Kohn theorem of the density functional theory is extended by modifying the Levy constrained-search formulation. The new theorem allows us to choose arbitrary physical quantities as the basic variables which determine the ground-state ...
Higuchi, K., Higuchi, M.
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Multiple solutions in systems of functional differential equations [PDF]
Journal of Mathematical Economics, 2014 This paper proposes conditions for the existence and uniqueness of solutions to systems of linear differential or algebraic equations with delays or advances, in which some variables may be non-predetermined. These conditions represent the counterpart to the Blanchard and Kahn conditions for the functional equations under consideration.
d'Albis, Hippolyte +2 more
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Stability results for the functional differential equations associated to water hammer in hydraulics
Electronic Journal of Qualitative Theory of Differential Equations, 2022 There is considered a system of two sets of partial differential equations describing the water hammer in a hydroelectric power plant containing the dynamics of the tunnel, turbine penstock, surge tank and hydraulic turbine.
Vladimir Rasvan
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CANONICAL APPROXIMATIONS IN IMPULSE STABILIZATION FOR A SYSTEM WITH AFTEREFFECT
Ural Mathematical Journal, 2023 For optimal stabilization of an autonomous linear system of differential equations with aftereffect and impulse controls, the formulation of the problem in the functional state space is used.
Yuri F. Dolgii
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Superstring 'ending' on super-D9-brane: a supersymmetric action functional for the coupled brane system [PDF]
, 1999 A supersymmetric action functional describing the interaction of the fundamental superstring with the D=10, type IIB Dirichlet super-9-brane is presented. A set of supersymmetric equations for the coupled system is obtained from the action principle.
Aganagic +70 more
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Infinite Systems of Hyperbolic Functional Differential Equations [PDF]
Ukrainian Mathematical Journal, 2003 Summary: We consider initial-value problems for infinite systems of first-order partial functional differential equations. The unknown function is the functional argument in equations and the partial derivations appear in the classical sense. A theorem on the existence of a solution and its continuous dependence upon initial data is proved.
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