3,888 research outputs found
Blocking optimal -arborescences
Given a digraph and a positive integer , an arc set is called a \textbf{-arborescence} if it is the disjoint union of
spanning arborescences. The problem of finding a minimum cost -arborescence
is known to be polynomial-time solvable using matroid intersection. In this
paper we study the following problem: find a minimum cardinality subset of arcs
that contains at least one arc from every minimum cost -arborescence. For
, the problem was solved in [A. Bern\'ath, G. Pap , Blocking optimal
arborescences, IPCO 2013]. In this paper we give an algorithm for general
that has polynomial running time if is fixed
Mixed duopolies with advance production
Production to order and production in advance has been compared in many frameworks. In this paper we investigate a mixed production in advance version of the capacity-constrained Bertrand-Edgeworth duopoly game and determine the solution of the respective timing game. We show that a pure-strategy (subgame-perfect) Nash-equilibrium point exists for all possible orderings of moves. It is pointed out that unlike the production-to-order case, the equilibrium of the timing game lies at simultaneous moves. An analysis of the public firm's impact on social welfare is also carried out. All the results are compared to those of the production-to order version of the respective game
Elastic, thermal expansion, plastic and rheological processes - theory and experiment
Rocks are important examples for solid materials where, in various
engineering situations, elastic, thermal expansion, rheological/viscoelastic
and plastic phenomena each may play a remarkable role. Nonequilibrium continuum
thermodynamics provides a consistent way to describe all these aspects in a
unified framework. This we present here in a formulation where the kinematic
quantities allow arbitrary nonzero initial (e.g., in situ) stresses and such
initial configurations which - as a consequence of thermal or remanent stresses
- do not satisfy the kinematic compatibility condition. The various
characteristic effects accounted by the obtained theory are illustrated via
experimental results where loaded solid samples undergo elastic, thermal
expansion and plastic deformation and exhibit rheological behaviour. From the
experimental data, the rheological coefficients are determined, and the
measured temperature changes are also explained by the theory.Comment: 15 pages, to appear in Period. Polytech. Civil En
Does timing of decisions in a mixed duopoly matter?
We determine the endogenous order of moves in a mixed price-setting duopoly. In contrast to the existing literature on mixed oligopolies we establish the payoff equivalence of the games with an exogenously given order of moves. Hence, it does not matter whether one becomes a leader or a follower. We also establish that replacing a private firm by a public firm in the standard Bertrand-Edgeworth game with capacity constraints increases social welfare and that a pure-strategy equilibrium always exists.Bertrand-Edgeworth; mixed duopoly; timing games
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