๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Convexity of minimal total dominating functions in graphs

โœ Scribed by Yu, Bo


Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
122 KB
Volume
24
Category
Article
ISSN
0364-9024

No coin nor oath required. For personal study only.

โœฆ Synopsis


A total dominating function (TDF) of a graph G = (V, E) is a function f : V โ†’ [0, 1] such that for each v โˆˆ V , the sum of f values over the open neighbourhood of v is at least one. Zero-one valued TDFs are precisely the characteristic functions of total dominating sets of G. We study the convexity of minimal total dominating functions. A minimal total dominating function (MTDF) f is called universal if convex combinations of f and any other MTDF are minimal. Generalizing and unifying two previous major results by Cockayne, Mynhardt and Yu in the area, we give a stronger sufficiency condition for an MTDF to be universal. Moreover, we define a splitting operation on a graph G, which preserves the universality. Using the operation, we give many more classes of graphs having a universal MTDF.


๐Ÿ“œ SIMILAR VOLUMES


Total domination in graphs with minimum
โœ Favaron, Odile; Henning, Michael A.; Mynhart, Christina M.; Puech, Jo๏ฟฝl ๐Ÿ“‚ Article ๐Ÿ“… 2000 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 132 KB ๐Ÿ‘ 2 views

A set S of vertices of a graph G is a total dominating set, if every vertex of V (G) is adjacent to some vertex in S. The total domination number of G, denoted by ฮณ t (G), is the minimum cardinality of a total dominating set of G. We prove that, if G is a graph of order n with minimum degree at leas

On equality in an upper bound for domina
โœ Favaron, O.; Mynhardt, C. M. ๐Ÿ“‚ Article ๐Ÿ“… 1997 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 141 KB ๐Ÿ‘ 2 views

We consider the well-known upper bounds ยต(G) โ‰ค |V (G)|-โˆ†(G), where โˆ†(G) denotes the maximum degree of G and ยต(G) the irredundance, domination or independent domination numbers of G and give necessary and sufficient conditions for equality to hold in each case. We also describe specific classes of gr

Functional dominance of the right corona
โœ Christos E. Nerantzis; John C.H. Papachristos; Joan E. Gribizi; Vasilis A. Voudr ๐Ÿ“‚ Article ๐Ÿ“… 1996 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 371 KB ๐Ÿ‘ 1 views

After injection of radiopaque medium, 200 human hearts were studied by direct observation and x-ray analysis. The right coronary artery (RC) was dominant in 178 of these hearts as characterized by giving off the typical posterior interventricular artery (PIV), the posterior descending artery. Within