Abstract. This paper advocates need for a formal foundation for refactoring object-oriented software. More specifically, it investigates the potential of graph rewriting as candidate formalism. Using a small Java application as a case study, it shows how a range of different notions of behaviour preservation can be expressed in a formal, yet intuitive, way. A number of other open research topic...

We obtain some improved upper and lower bounds on the oriented chromatic number for different classes of products of graphs.

Within the premises of the flux-oriented theory of Crabtree & Newsholme [(1987) Biochem. J. 247, 113-120], I have used a graph-theoretic approach for calculating the Control Coefficients of metabolic pathways. It is shown that a directed graph representing the control structure of a metabolic pathway can be constructed in a heuristic manner directly from the reaction diagram of the pathway, wit...

Our purpose is to introduce the concept of determining the smallest number of edges of a graph which can be oriented so that the resulting mixed graph has the trivial automorphism group. We find that this number for complete graphs is related to the number of identity oriented trees. For complete bipartite graphs Ks,t, s ≤ t, this number does not always exist. We determine for s ≤ 4 the values ...

Abstract: Two different ways of obtaining generalized low-density parity-check codes are considered. Lower bounds on the minimum distance, stopping distance, and pseudodistance are derived for these codes using graph based analysis. These bounds are generalizations of Tanner’s bit-oriented and parity-oriented bound for simple LDPC codes. The new bounds are useful in predicting the performance o...

The precise specification of software models is a major concern in the model-driven design of object-oriented software. Models are commonly given as graph-like diagrams so that graph grammars are a natural candidate for specifying them. However, context-free graph grammars are not powerful enough to specify all static properties of a model. Even the recently proposed adaptive star grammars cann...

This paper presents a new method for image retrieval using a graph object oriented database for processing the information extracted from the image through the segmentation process and through the semantic interpretation of this information. The object oriented database schema is structured as a classes hierarchy based on graph data structure. A graph structure is used in all phases of the imag...

Thomassen introduced the concept of a finitely spreading graph: an infinite graph whose edges can be oriented, each in one, both, or neither direction, so that every vertex has finite out-degree and every ray has a forward oriented tail. He conjectured that a graph is finitely spreading if and only if it is bounded in the sense of Halin—equivalently (see [5]), if it contains none of three speci...

An adaptive program can be understood as an object-oriented program where the class graph is a parameter, and hence the class graph may be changed without changing the program. The problem of compiling an adaptive program and a class graph into an object-oriented program was studied by Palsberg, Xiao, and Lieberherr in 1995. Their compiler is efficient but works only in special cases. In this p...

The set A of distinct scores of the vertices of an oriented bipartite graph D(U, V) is called its score set. We consider the following question: given a finite, nonempty set A of positive integers, is there an oriented bipartite graph D(U, V) such that score set of D(U, V) is A? We conjecture that there is an affirmative answer, and verify this conjecture when | A | = 1, 2, 3, or when A is a ge...