Control and inverse problems in wave equations and graphs constitute a dynamic field at the intersection of applied mathematics, engineering and physics. This area investigates how waves propagating ...

We develop a theory of graph C*-algebras using path groupoids and inverse semigroups. Row finiteness is not assumed so that the theory applies to graphs for which there are vertices emitting a ...

The inverse degree of a graph G with no isolated vertices is defined as the sum of reciprocal of vertex degrees of the graph G. In this paper, we obtain several lower and upper bounds on inverse ...

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Drazin inverses and their modern generalisations constitute a pivotal area of operator theory within Banach algebras. These inverse concepts extend the classic notion of the matrix inverse to settings ...

In this graph, 𝑥 and 𝑦 are directly proportional. This means that when 𝑥 doubles, 𝑦 also doubles, and when 𝑥 triples, so does 𝑦. In fact, for all coordinates on this line, you could multiply or ...