Gopalapillai,Indulal; Ivan,Gutman; Vijayakumar,Ambat(Department of Mathematics, August 25, 2007)

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Abstract:

The D-eigenvalues of a graph G are the eigenvalues of its distance matrix D, and the
D-energy ED(G) is the sum of the absolute values of its D-eigenvalues. Two graphs are
said to be D-equienergetic if they have the same D-energy. In this note we obtain bounds
for the distance spectral radius and D-energy of graphs of diameter 2. Pairs of equiregular
D-equienergetic graphs of diameter 2, on p = 3t + 1 vertices are also constructed.

Indulal,G; Vijayakumar,A(Springer, October , 2007)

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Abstract:

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.

Krishnamoorthy,A; Vishwanath, Narayanan C; Deepak,T G(Korean Society for Computational & Applied mathematics, 2007)

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Abstract:

In this paper, we study a k-out-of-n system with single server
who provides service to external customers also. The system consists of
two parts:(i) a main queue consisting of customers (failed components of
the k-out-of-n system) and (ii) a pool (of finite capacity M) of external
customers together with an orbit for external customers who find the pool
full. An external customer who finds the pool full on arrival, joins the orbit
with probability
and with probability 1−
leaves the system forever. An
orbital customer, who finds the pool full, at an epoch of repeated attempt,
returns to orbit with probability (< 1) and with probability 1 − leaves
the system forever. We compute the steady state system size probability.
Several performance measures are computed, numerical illustrations are
provided.