Carmina Georgescu

Polytechnic University of Bucharest | UPB · Department of Mathematical Methods and Models

In this paper we generalize some classical edge detectors using the second-order Riesz fractional derivative. Taking advantages of fractional differential method we improve the shortcomings of conventional operators like Roberts, Prewitt and Sobel. Consequently, three improved edge detection algorithms are gained. The experimental results show that...

In this paper we generalize some classical edge detectors using the second-order Riesz fractional derivative. Taking advantages of fractional differential method we improve the shortcomings of conventional operators like Roberts, Prewitt and Sobel. Consequently, three improved edge detection algorithms are gained. The experimental results show that...

The paper deals with good gradings over torsion-free Abelian groups. We derive first necessary conditions in order for two good gradings to be isomorphic with respect to the algebra of polynomial ring in n variables. Next we study the case of good gradings over the integer numbers group and give an equivalent condition in order to be isomorphic. Eq...

This talk is about the importance of randomness in cryptographic design primitives.

This paper reviews the relationships between switching systems defined from a partition of the state space into convex cells, and relay or complementarity dynamical systems, which are other classes of discontinuous systems. Well-posedness results (i.e. results on the existence and the uniqueness of solutions) for different classes of relay and comp...

In this paper, a new class of fractional-order discontinuous-time systems containing relays is introduced and sufficient conditions for the uniqueness of solutions are established. By using the Laplace transform, we show that the technique proposed in [Y. J. Lootsma et al., Automatica 35, No. 3, 467–478 (1999; Zbl 0947.93021)] for linear relay syst...

In this work, the authors studies conditions that a real quadratic form is kept invariant by some matrices. In Section 1 some examples are given and in Section 3, one studies the group of matrice which keep invariant the Pythagorean form x 2 +y 2 -z 2 and one indicates a procedure to get systematically the solutions of the Diophantine equation x 2...

In this paper we prove the existence of random solutions for neutral functional integrodifferential inclusions with lower semicontinuous and nonconvex-valued right-hand side. Then we establish a sufficient condition for the existence of viable solutions to yield the existence of random viable solutions to neutral functional integrodifferential incl...

This paper is devoted to the study of neutral functional differential inclusions defined on a separable Banach space and depending in a measurable way on a random parameter. We first prove an existence result for a class of neutral functional differential inclusions with memory. Then we establish a condition under which the existence of viable solu...

This paper is devoted to the study of functional-differential inclusions with memory defined on a separable Banach space and depending in a measurable way on a random parameter. Two existence theorems are obtained through the use of analogous deterministic results and techniques from the theory of measurable multifunctions.

We consider the Mayer optimal control problem with dynamics given by a nonconvex differential–difference inclusion, whose trajectories are constrained to a closed set. Necessary optimality conditions in the form of the maximum principle are obtained.

We study an optimization problem given by a discrete delay inclusion with end point constraints. Necessary optimality conditions in the form of maximum principle for this problem are obtained.