The main objective of this article is to review the major progress that has been made on controllability of dynamical systems over the past number of years. Controllability is one of the fundamental concepts in the mathematical control theory. This is a qualitative property of dynamical control systems and is of particular importance in control theory. A systematic study of controllability was ...

A common problem in frequent graph mining is the size of the output, which can easily exceed the size of the database to analyze. In the application area of molecular fragment mining a promising approach to tackle this problem is to treat certain substructures as a unit. Among such structures, rings are most prominent, and by requiring that either a ring is present as a whole in a fragment, or ...

In frequent subgraph mining one tries to find all subgraphs that occur with a user-specified minimum frequency in a given graph database. The basic approach is to grow subgraphs, adding an edge and maybe a node in each step, to count the number of database graphs containing them, and to eliminate infrequent subgraphs. The predominant method to avoid redundant search (the same subgraph can be gr...

A canonical form for circuit diagrams with a designated start state is presented. The form is based upon nite automata minimization and Shannon's canonical form for boolean expressions.

Given a linear time-invariant control system, it is well known that the transmission zeroes are the generalized eigenvalues of a matrix pencil. Adding outputs to place additional zeroes is equivalent to appending rows to this pencil to place new generalized eigenvalues. Adding inputs is likewise equivalent to appending columns. Since both problems are dual to each other, we only show in this pa...

In this paper, we give a characterization of strongly Jordan zero-product preserving maps on normed algebras as a generalization of  Jordan zero-product preserving maps. In this direction, we give some illustrative examples to show that the notions of strongly zero-product preserving maps and strongly Jordan zero-product preserving maps are completely different. Also, we prove that the direct p...

In this article, we study geometric unitaries of JB-algebras (in particular, self-adjoint parts of C∗-algebras). We will show that the geometric unitaries of a JB algebra are precisely those central algebraic unitaries (or central symmetries). We will also show that the group of surjective isometries on a JB-algebra A (with point-norm topology) is the semi-direct product of the canonical action...