Mihaela Tomescu - Academia.edu (original) (raw)
Papers by Mihaela Tomescu
In this paper we study two concepts of exponential stability for variational nonautonomous differ... more In this paper we study two concepts of exponential stability for variational nonautonomous difference equations in Banach spaces. Characterizations of these concepts are given. The obtained results can be considered as generalizations for variational nonautonomous difference equations of some well-known theorems due to Barbashin and Datko .
Mathematics, 2021
A series of counting, sequence and layer matrices are considered precursors of classifiers capabl... more A series of counting, sequence and layer matrices are considered precursors of classifiers capable of providing the partitions of the vertices of graphs. Classifiers are given to provide different degrees of distinctiveness for the vertices of the graphs. Any partition can be represented with colors. Following this fundamental idea, it was proposed to color the graphs according to the partitions of the graph vertices. Two alternative cases were identified: when the order of the sets in the partition is relevant (the sets are distinguished by their positions) and when the order of the sets in the partition is not relevant (the sets are not distinguished by their positions). The two isomers of C28 fullerenes were colored to test the ability of classifiers to generate different partitions and colorings, thereby providing a useful visual tool for scientists working on the functionalization of various highly symmetrical chemical structures.
The aim of this paper is to present numerical methods for solving nonlinear equations and some ex... more The aim of this paper is to present numerical methods for solving nonlinear equations and some examples in which we find the roots of this equations using Mathematica.
In this paper is present the economic models with discrete time. An economic model is followed of... more In this paper is present the economic models with discrete time. An economic model is followed of numerical program in Matlab, which exemplify the state of equilibrium.
Symmetry, 2021
Protein alignment finds its application in refining results of sequence alignment and understandi... more Protein alignment finds its application in refining results of sequence alignment and understanding protein function. A previous study aligned single molecules, making use of the minimization of sums of the squares of eigenvalues, obtained for the antisymmetric Cartesian coordinate distance matrices Dx and Dy. This is used in our program to search for similarities between amino acids by comparing the sums of the squares of eigenvalues associated with the Dx, Dy, and Dz distance matrices. These matrices are obtained by removing atoms that could lead to low similarity. Candidates are aligned, and trilateration is used to attach all previously striped atoms. A TM-score is the scoring function that chooses the best alignment from supplied candidates. Twenty essential amino acids that take many forms in nature are selected for comparison. The correct alignment is taken into account most of the time by the alignment algorithm. It was numerically detected by the TM-score 70% of the time, o...
Annals of West University of Timisoara - Mathematics, 2013
In this paper we give characterizations for uniform polynomial stability property of variational ... more In this paper we give characterizations for uniform polynomial stability property of variational nonautonomous difference equations. We obtain results that generalize the well-known theorems due to R.Datko ([3]), E.Barbashin ([1]) and A.Lyapunov ([4]) for variational nonautonomous difference equations.
Our goal in this paper is to give characterizations for some concepts of polynomial stability for... more Our goal in this paper is to give characterizations for some concepts of polynomial stability for variational nonautonomous difference equations. The obtained results can be considered generalizations for the case of variational nonautonomous difference equations of some theorems proved by Barbashin (1967), Datko (1973), and Lyapunov (1992), for evolution operators.
In this paper we study two concepts of exponential stability for variational nonautonomous differ... more In this paper we study two concepts of exponential stability for variational nonautonomous difference equations in Banach spaces. Characterizations of these concepts are given. The obtained results can be considered as generalizations for variational nonautonomous difference equations of some well-known theorems due to Barbashin and Datko .
Mathematics, 2021
A series of counting, sequence and layer matrices are considered precursors of classifiers capabl... more A series of counting, sequence and layer matrices are considered precursors of classifiers capable of providing the partitions of the vertices of graphs. Classifiers are given to provide different degrees of distinctiveness for the vertices of the graphs. Any partition can be represented with colors. Following this fundamental idea, it was proposed to color the graphs according to the partitions of the graph vertices. Two alternative cases were identified: when the order of the sets in the partition is relevant (the sets are distinguished by their positions) and when the order of the sets in the partition is not relevant (the sets are not distinguished by their positions). The two isomers of C28 fullerenes were colored to test the ability of classifiers to generate different partitions and colorings, thereby providing a useful visual tool for scientists working on the functionalization of various highly symmetrical chemical structures.
The aim of this paper is to present numerical methods for solving nonlinear equations and some ex... more The aim of this paper is to present numerical methods for solving nonlinear equations and some examples in which we find the roots of this equations using Mathematica.
In this paper is present the economic models with discrete time. An economic model is followed of... more In this paper is present the economic models with discrete time. An economic model is followed of numerical program in Matlab, which exemplify the state of equilibrium.
Symmetry, 2021
Protein alignment finds its application in refining results of sequence alignment and understandi... more Protein alignment finds its application in refining results of sequence alignment and understanding protein function. A previous study aligned single molecules, making use of the minimization of sums of the squares of eigenvalues, obtained for the antisymmetric Cartesian coordinate distance matrices Dx and Dy. This is used in our program to search for similarities between amino acids by comparing the sums of the squares of eigenvalues associated with the Dx, Dy, and Dz distance matrices. These matrices are obtained by removing atoms that could lead to low similarity. Candidates are aligned, and trilateration is used to attach all previously striped atoms. A TM-score is the scoring function that chooses the best alignment from supplied candidates. Twenty essential amino acids that take many forms in nature are selected for comparison. The correct alignment is taken into account most of the time by the alignment algorithm. It was numerically detected by the TM-score 70% of the time, o...
Annals of West University of Timisoara - Mathematics, 2013
In this paper we give characterizations for uniform polynomial stability property of variational ... more In this paper we give characterizations for uniform polynomial stability property of variational nonautonomous difference equations. We obtain results that generalize the well-known theorems due to R.Datko ([3]), E.Barbashin ([1]) and A.Lyapunov ([4]) for variational nonautonomous difference equations.
Our goal in this paper is to give characterizations for some concepts of polynomial stability for... more Our goal in this paper is to give characterizations for some concepts of polynomial stability for variational nonautonomous difference equations. The obtained results can be considered generalizations for the case of variational nonautonomous difference equations of some theorems proved by Barbashin (1967), Datko (1973), and Lyapunov (1992), for evolution operators.