http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/479 Wed, 22 May 2013 04:18:09 GMT 2013-05-22T04:18:09Z http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2861 Convex extendable trees Parvathy, K S; Vijayakumar, A The concept of convex extendability is introduced to answer the problem of finding the smallest distance convex simple graph containing a given tree. A problem of similar type with respect to minimal path convexity is also discussed. Fri, 01 Jan 1999 00:00:00 GMT http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2861 1999-01-01T00:00:00Z http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2860 A characterization of fuzzy trees Sunitha, M S; Vijayakumar, A In this paper some properties of fuzzy bridges are studied.A characterization of fuzzy trees is obtained using these concepts. Fri, 01 Jan 1999 00:00:00 GMT http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2860 1999-01-01T00:00:00Z http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2859 Clique Irreducibility and Clique Vertex Irreducibility of Graphs Aparna, Lakshmanan S; Vijayakumar, A. A graphs G is clique irreducible if every clique in G of size at least two,has an edge which does not lie in any other clique of G and is clique reducible if it is not clique irreducible. A graph G is clique vertex irreducible if every clique in G has a vertex which does not lie in any other clique of G and clique vertex reducible if it is not clique vertex irreducible. The clique vertex irreducibility and clique irreducibility of graphs which are non-complete extended p-sums (NEPS) of two graphs are studied. We prove that if G(c) has at least two non-trivial components then G is clique vertex reducible and if it has at least three non-trivial components then G is clique reducible. The cographs and the distance hereditary graphs which are clique vertex irreducible and clique irreducible are also recursively characterized. Thu, 01 Jan 2009 00:00:00 GMT http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2859 2009-01-01T00:00:00Z http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2038 Energies of some non-regular graphs Indulal, G; Vijayakumar, A The energy of a graph G is the sum of the absolute values of its eigenvalues. In this paper, we study the energies of some classes of non-regular graphs. Also the spectrum of some non-regular graphs and their complements are discussed. Mon, 01 Oct 2007 00:00:00 GMT http://dyuthi.cusat.ac.in:80/xmlui/handle/purl/2038 2007-10-01T00:00:00Z