Results 231 to 240 of about 74,219 (267)
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Deformations of quadratic Diophantine systems
Izvestiya: Mathematics, 2001Consider the matrix equation \(Q[X] = {^tX}QX = A\), where \(Q\) and \(A\) are positive definite symmetric integral matrices of order \(n\) and \(m\), respectively, and \(X\) ranges over the set of \(n\times m\) integer matrices. The author studies the relationship between solutions to this equation and corresponding equations \(K'[Y]=A''\) obtained by
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Error Bounds for Quadratic Systems
2000In this paper we consider the problem of estimating the distance from a given point to the solution set of a quadratic inequality system. We show, among other things, that a local error bound of order 1/2 holds for a system defined by linear inequalities and a single (nonconvex) quadratic equality.
Luo, Z-Q, Sturm, J.F.
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1997
Linear systems with a quadratic performance criterion attract the attention of many investigations for the following reasons: they describe many actual phenomena adequately enough; on the other hand, the corresponding optimal control problems, as a rule, can be completely solved analytically.
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Linear systems with a quadratic performance criterion attract the attention of many investigations for the following reasons: they describe many actual phenomena adequately enough; on the other hand, the corresponding optimal control problems, as a rule, can be completely solved analytically.
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Quantum Langevin equation: a quadratic system
Journal of Physics A: Mathematical and General, 1990Summary: A system described by a quadratic Hamiltonian with a two-photon absorption and emission term is coupled to heat bath, described by either a non-Hermitian or a Hermitian noise operator. The dissipation kernel is memory dependent. A set of dispersion relations for the bath distribution functions is obtained.
Chakrabarti, R., Vasudevan, R.
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Quadratic Nonlinear Discrete Systems
2020In this Chapter, the global stability and bifurcation of quadratic nonlinear discrete systems are discussed. Appearing and switching bifurcations of simple period-1 fixed-points are discussed. Period-1 and period-2 bifurcation trees with global stability are presented for forward and backward quadratic discrete systems.
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The Quadratic Criterion for Distributed Systems
SIAM Journal on Control, 1969Abstract : The article explores the applicability of the quadratic criterion of optimality to the control of distributed parameter systems or, alternatively, to differential equations in a Hilbert space. It is shown that such application is indeed possible and, perhaps more important from the engineering point of view, that the optimal controls thus ...
Lukes, D. L., Russell, D. L.
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Two Dimensional Homogeneous Quadratic Differential Systems
SIAM Review, 1978The two-dimensional quadratic differential system (QDS) \[ \begin{gathered} \dot x = a_1 x^2 + b_1 xy + c_1 y^2 , \hfill \\ \dot y = a_2 x^2 + b_2 xy + c_2 y^2 \hfill \\ \end{gathered} \] where $( \cdot ) = {d} / {dt}$ and the coefficients are real constants is considered.
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Quadratic Residue Number Systems
2002Complex signal processing can be handled by RNS in a manner similar to standard complex number operations such as addition, subtraction, multiplication etc. However, under certain special cases of choice of moduli, the complete decoupling of computation of real and imaginary parts of the result is feasible.
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Temporal walk-off induced dissipative quadratic solitons
Nature Photonics, 2022Arkadev Roy, Rajveer Nehra, Saman Jahani
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