42,889 research outputs found
Fuzzy set applications in engineering optimization: Multilevel fuzzy optimization
A formulation for multilevel optimization with fuzzy objective functions is presented. With few exceptions, formulations for fuzzy optimization have dealt with a one-level problem in which the objective is the membership function of a fuzzy set formed by the fuzzy intersection of other sets. In the problem examined here, the goal set G is defined in a more general way, using an aggregation operator H that allows arbitrary combinations of set operations (union, intersection, addition) on the individual sets Gi. This is a straightforward extension of the standard form, but one that makes possible the modeling of interesting evaluation strategies. A second, more important departure from the standard form will be the construction of a multilevel problem analogous to the design decomposition problem in optimization. This arrangement facilitates the simulation of a system design process in which different components of the system are designed by different teams, and different levels of design detail become relevant at different time stages in the process: global design features early, local features later in the process
Conserved quantities for a charged rotating black holes in 5D Einstein-Maxwell-Chern-Simons theory
Indexación: Scopus.In this work, we compute the conserved quantities of a charged rotating black hole which appears as the solution of Einstein-Maxwell action in five dimensions coupled to a Chern-Simons term for U(1) field. The addition of the Chern-Simons term will modify the Maxwell equations and the definition of charge but not the Einstein field equations. Upon the addition of suitable boundary terms for the pure gravity sector of the theory, which depend on the extrinsic and intrinsic curvatures (Kounterterms), we obtain the correct conserved quantities of the solution. © Published under licence by IOP Publishing Ltd.We thank Giorgos Anastasiou and David Rivera-Betancour for insightful discussions. This work was funded in part by FONDECYT Grant 1131075, UNAB Grant DI-1336-16/RG and CONICYT Grant DPI 20140115.https://iopscience.iop.org/article/10.1088/1742-6596/1043/1/01202
Axigluon Phenomenology using ATLAS dijet data
In recent years, there has been a renewed interest on axigluons as part of a
possible extension of strong interactions at high energies. In this work, we
use recent ATLAS measurements of the dijet spectrum in order to set limits on
the axigluon mass and coupling to quarks. We pay special attention to the
methodology used to extract the resonant contribution from theoretical
simulations. Finally, we present some predictions for the next LHC run at
TeV
Infusion extractor
This invention relates to an apparatus and method of removing desirable constituents from an infusible material by infusion extraction. A piston operating in a first chamber draws a solvent into the first chamber where it may be heated, and then moves the heated solvent into a second chamber containing the infusible material, where infusion extraction takes place. The piston then moves the solvent containing the extract through a filter into the first chamber, leaving the extraction residue in the second chamber. The method is applicable to operation in low or micro-gravity environments
History state formalism for Dirac's theory
We propose a history state formalism for a Dirac particle. By introducing a
reference quantum clock system it is first shown that Dirac's equation can be
derived by enforcing a timeless Wheeler-DeWitt-like equation for a global
state. The Hilbert space of the whole system constitutes a unitary
representation of the Lorentz group with respect to a properly defined
invariant product, and the proper normalization of global states directly
ensures standard Dirac's norm. Moreover, by introducing a second quantum clock,
the previous invariant product emerges naturally from a generalized continuity
equation. The invariant parameter associated with this second clock
labels history states for different particles, yielding an observable evolution
in the case of an hypothetical superposition of different masses. Analytical
expressions for both space-time density and electron-time entanglement are
provided for two particular families of electron's states, the former including
Pryce localized particles.Comment: 9 pages, 2 figures, final versio
A Tool for Integer Homology Computation: Lambda-At Model
In this paper, we formalize the notion of lambda-AT-model (where is
a non-null integer) for a given chain complex, which allows the computation of
homological information in the integer domain avoiding using the Smith Normal
Form of the boundary matrices. We present an algorithm for computing such a
model, obtaining Betti numbers, the prime numbers p involved in the invariant
factors of the torsion subgroup of homology, the amount of invariant factors
that are a power of p and a set of representative cycles of generators of
homology mod p, for each p. Moreover, we establish the minimum valid lambda for
such a construction, what cuts down the computational costs related to the
torsion subgroup. The tools described here are useful to determine topological
information of nD structured objects such as simplicial, cubical or simploidal
complexes and are applicable to extract such an information from digital
pictures.Comment: Journal Image and Vision Computing, Volume 27 Issue 7, June, 200
Improving bounds on flavor changing vertices in the two Higgs doublet model from mixing
We find some constraints on the flavor changing vertices of the two Higgs
doublet model, from the \Delta M_{B_{d}} measurement. Although bounds from this
observable have already been considered, this paper takes into account the role
of a new operator not included previously, as well as the vertices \xi_{bb},
\xi_{tc} and \xi_{sb}. Using the Cheng-Sher parametrization, we found that for
a relatively light charged Higgs boson (200-300 GeV), we get that \lambda
_{tt}<1, while the parameter \lambda_{bb} could have values up to about 50. In
addition, we use bounds for \lambda_{tt} and \lambda_{bb} obtained from
B^{0}->X_{s}\gamma at next to leading order, and studied the case where the
only vanishing vertex factors are the ones involving quarks from the first
family. We obtained that \Delta M_{B_{d}} is not sensitive to the change of the
parameter \lambda_{sb}, while \lambda_{tc}<1Comment: 4 pages, 1 figure, LaTeX2
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