3,983 research outputs found
Dominating Set Games
In this paper we study cooperative cost games arising from domination problems on graphs.We introduce three games to model the cost allocation problem and we derive a necessary and su cient condition for the balancedness of all three games.Furthermore we study concavity of these games.game theory;cost allocation;cooperative games
Simple Combinatorial Optimisation Cost Games
In this paper we introduce the class of simple combinatorial optimisation cost games, which are games associated to {0, 1}-matrices.A coalitional value of a combinatorial optimisation game is determined by solving an integer program associated with this matrix and the characteristic vector of the coalition.For this class of games, we will characterise core stability and totally balancedness.We continue by characterising exactness and largeness.Finally, we conclude the paper by applying our main results to minimum colouring games and minimum vertex cover games.Combinatorial optimisation game;core stability;totally balancedness;largeness;exactness
Sequencing Games with Controllable Processing Time
In this paper we study a class of cooperative sequencing games that arise from sequencing situations in which the processing times are not fixed.We show that these games are balanced by obtaining two core elements that depend only on the optimal schedule for the grand coalition.Furthermore we show that, although these games are not convex in general, many marginal vectors are core elements. We also consider convexity for special instances of the sequencing situation.cooperative games
Measurement of the rate of stellar tidal disruption flares
We report an observational estimate of the rate of stellar tidal disruption
flares (TDFs) in inactive galaxies, based on a successful search for these
events among transients in galaxies using archival SDSS multi-epoch imaging
data (Stripe 82). This search yielded 186 nuclear flares in galaxies, of which
two are excellent TDF candidates. Because of the systematic nature of the
search, the very large number of galaxies, the long time of observation, and
the fact that non-TDFs were excluded without resorting to assumptions about TDF
characteristics, this study provides an unparalleled opportunity to measure the
TDF rate. To compute the rate of optical stellar tidal disruption events, we
simulate our entire pipeline to obtain the efficiency of detection. The rate
depends on the light curves of TDFs, which are presently still poorly
constrained. Using only the observed part of the SDSS light curves gives a
model-independent upper limit to the optical TDF rate: < 2 10^-4 per year per
galaxy (90% CL). We develop three empirical models of the light curves, based
on the two SDSS light curves and two more recent and better-sampled Pan-STARRS
TDF light curves, leading to our best-estimate of the rate: (1.5 -
2.0)_{-1.3}^{+2.7} 10^-5 per year per galaxy. We explore the modeling
uncertainties by considering two theoretically motivated light curve models, as
well as two different relationships between black hole mass and galaxy
luminosity, and two different treatments of the cutoff in the visibility of
TDFs at large black hole mass. From this we conclude that these sources of
uncertainty are not significantly larger than the statistical ones. Our results
are applicable for galaxies hosting black holes with mass in the range of few
million to 10^8 solar masses, and translates to a volumetric TDF rate of (4 -
8) 10^-8 per year per cubic Mpc.Comment: Published in Ap
On the Balancedness of Relaxed Sequencing Games
This paper shows that some classes of relaxed sequencing games, which arise from the class of sequencing games as introduced in Curiel, Pederzoli, Tijs (1989), are balanced.sequencing situations;sequencing games;balancedness;game theory
Solvent extraction as additional purification method for postconsumer plastic packaging waste
An existing solvent extraction process currently used to convert lightly polluted post-industrial packaging waste into high quality re-granulates was tested under laboratory conditions with highly polluted post-consumer packaging waste originating from municipal solid refuse waste. The objective was to study the technical feasibility of using this extraction technology and to study the quality of the produced cleaned plastic flakes. Two types of dirty plastic flakes from household waste were used; transparent to white flexible film flakes and PET-bottle flakes
Convexity and Marginal Vectors
In this paper we construct sets of marginal vectors of a TU game with the property that if the marginal vectors from these sets are core elements, then the game is convex.This approach leads to new upperbounds on the number of marginal vectors needed to characterize convexity.An other result is that the relative number of marginals needed to characterize convexity converges to zero.game theory;convexity;marginal vectors
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