Zobrazeno 1 - 10
of 85
pro vyhledávání: '"Comănescu, Dan"'
Autor:
Comănescu, Dan
We prove that the following statements are equivalent: a linear matrix equation with parameters forming a commuting set of diagonalizable matrices is consistent, a certain matrix constructed with the Drazin inverse is a solution of this matrix equati
Externí odkaz:
http://arxiv.org/abs/2406.09429
Autor:
Comănescu, Dan
The steady states of an antitone electric system are described by an antitone function with respect to the componentwise order. When this function is bounded from below by a positive vector, it has only one fixed point. This fixed point is attractive
Externí odkaz:
http://arxiv.org/abs/2305.16268
Autor:
Comănescu, Dan
The steady states of an isotone electric system are described by an isotone function with respect to the componentwise order. When there are steady states, we highlight a dominant steady state and we study its domain of attraction for the fixed point
Externí odkaz:
http://arxiv.org/abs/2209.04208
Using the embedded gradient vector field method (see P. Birtea, D. Comanescu, Hessian operators on constraint manifolds, J. Nonlinear Science 25, 2015), we present a general formula for the Laplace-Beltrami operator defined on a constraint manifold,
Externí odkaz:
http://arxiv.org/abs/2206.06790
We develop the embedded gradient vector field method, introduced in [8] and [9], for the case of the special unitary group $\mathcal{SU}(N)$ regarded as a constraint submanifold of the unitary group $\mathcal{U}(N)$. The optimization problem associat
Externí odkaz:
http://arxiv.org/abs/2103.11132
Using the embedded gradient vector field method we explicitly compute the list of critical points of the free energy for a Cosserat body model. We also formulate necessary and sufficient conditions for critical points in the abstract case of the spec
Externí odkaz:
http://arxiv.org/abs/1907.04726
We regard the real symplectic group $Sp(2n,\mathbb{R})$ as a constraint submanifold of the $2n\times 2n$ real matrices $\mathcal{M}_{2n}(\mathbb{R})$ endowed with the Euclidean (Frobenius) metric, respectively as a submanifold of the general linear g
Externí odkaz:
http://arxiv.org/abs/1811.07345
Autor:
Comănescu, Dan
A Lyapunov matrix equation can be converted, by using the Jordan decomposition theorem for matrices, into an equivalent Lyapunov matrix equation where the matrix is a Jordan matrix. The Lyapunov matrix equation with Jordan matrix can be reduced to a
Externí odkaz:
http://arxiv.org/abs/1810.05033
The main tool to study a second order optimality problem is the Hessian operator associated to the cost function that defines the optimization problem. By regarding an orthogonal Stiefel manifold as a constraint manifold embedded in an Euclidean spac
Externí odkaz:
http://arxiv.org/abs/1802.05469
Considering orthogonal Stiefel manifolds as constraint manifolds, we give an explicit description of a set of local coordinates that also generate a basis for the tangent space in any point of the orthogonal Stiefel manifolds. We show how this constr
Externí odkaz:
http://arxiv.org/abs/1709.06295