4,410 research outputs found
Models of Consensus for Multiple Agent Systems
Models of consensus are used to manage multiple agent systems in order to
choose between different recommendations provided by the system. It is assumed
that there is a central agent that solicits recommendations or plans from other
agents. That agent the n determines the consensus of the other agents, and
chooses the resultant consensus recommendation or plan. Voting schemes such as
this have been used in a variety of domains, including air traffic control.
This paper uses an analytic model to study the use of consensus in multiple
agent systems. The binomial model is used to study the probability that the
consensus judgment is correct or incorrect. That basic model is extended to
account for both different levels of agent competence and unequal prior odds.
The analysis of that model is critical in the investigation of multiple agent
systems, since the model leads us to conclude that in some cases consensus
judgment is not appropriate. In addition, the results allow us to determine how
many agents should be used to develop consensus decisions, which agents should
be used to develop consensus decisions and under which conditions the consensus
model should be used.Comment: Appears in Proceedings of the Tenth Conference on Uncertainty in
Artificial Intelligence (UAI1994
Vevacious: A Tool For Finding The Global Minima Of One-Loop Effective Potentials With Many Scalars
Several extensions of the Standard Model of particle physics contain
additional scalars implying a more complex scalar potential compared to that of
the Standard Model. In general these potentials allow for charge and/or color
breaking minima besides the desired one with correctly broken SU(2)_L times
U(1)_Y . Even if one assumes that a metastable local minimum is realized, one
has to ensure that its lifetime exceeds that of our universe. We introduce a
new program called Vevacious which takes a generic expression for a one-loop
effective potential energy function and finds all the tree-level extrema, which
are then used as the starting points for gradient-based minimization of the
one-loop effective potential. The tunneling time from a given input vacuum to
the deepest minimum, if different from the input vacuum, can be calculated. The
parameter points are given as files in the SLHA format (though is not
restricted to supersymmetric models), and new model files can be easily
generated automatically by the Mathematica package SARAH. This code uses
HOM4PS2 to find all the minima of the tree-level potential, PyMinuit to follow
gradients to the minima of the one-loop potential, and CosmoTransitions to
calculate tunneling times.Comment: 44 pages, 1 figure, manual for publicly available software, v2
corresponds to version accepted for publication in EPJC [clearer explanation
of scale dependence and region of validity, explicit mention that SLHA files
should have blocks matching those expected by model files, updated
references
Validity of the CMSSM interpretation of the diphoton excess
It has been proposed that the observed diphoton excess at 750 GeV could be
explained within the constrained minimal supersymmetric standard model via
resonantly produced stop bound states. We reanalyze this scenario critically
and extend previous work to include the constraints from the stability of the
electroweak vacuum and from the decays of the stoponium into a pair of Higgs
bosons. It is shown that the interesting regions of parameter space with a
light stop and Higgs of the desired mass are ruled out by these constraints.
This conclusion is not affected by the presence of the bound states because the
binding energy is usually very small in the regions of parameter space which
can explain the Higgs mass. Thus, this also leads to strong constraints on the
diphoton production cross section which is in general too small.Comment: 8 pages, 5 figures; v2: added Fig. 5, matches published versio
Neural regulation of cardiovascular response to exercise: role of central command and peripheral afferents
During dynamic exercise, mechanisms controlling the cardiovascular apparatus operate to provide adequate oxygen to fulfill metabolic demand of exercising muscles and to guarantee metabolic end-products washout. Moreover, arterial blood pressure is regulated to maintain adequate perfusion of the vital organs without excessive pressure variations. The autonomic nervous system adjustments are characterized by a parasympathetic withdrawal and a sympathetic activation. In this review, we briefly summarize neural reflexes operating during dynamic exercise. The main focus of the present review will be on the central command, the arterial baroreflex and chemoreflex, and the exercise pressure reflex. The regulation and integration of these reflexes operating during dynamic exercise and their possible role in the pathophysiology of some cardiovascular diseases are also discusse
Implications of gauge kinetic mixing on Z' and slepton production at the LHC
We consider a supersymmetric version of the standard model extended by an
additional U(1)_{B-L}. This model can be embedded in an mSUGRA-inspired model
where the mass parameters of the scalars and gauginos unify at the scale of
grand unification. In this class of models the renormalization group equation
evolution of gauge couplings as well as of the soft SUSY-breaking parameters
require the proper treatment of gauge kinetic mixing. We first show that this
has a profound impact on the phenomenolgy of the Z' and as a consequence the
current LHC bounds on its mass are reduced significantly from about 1920 GeV to
1725 GeV. They are even further reduced if the Z' can decay into supersymmetric
particles. Secondly, we show that in this way sleptons can be produced at the
LHC in the 14 TeV phase with masses of several hundred GeV. In the case of
squark and gluino masses in the multi-TeV range, this might become an important
discovery channel for sleptons up to 650 GeV (800 GeV) for an integrated
luminosity of 100 fb^{-1} (300 fb^{-1}).Comment: 34 pages, 14 figures. v2: Significance equation corrected, results
qualitatively unchanged; minor changes in quantitative Z' bound
Leukotrienes provide an NFAT-dependent signal that synergizes with IL-33 to activate ILC2s.
Group 2 innate lymphoid cells (ILC2s) and type 2 helper T cells (Th2 cells) are the primary source of interleukin 5 (IL-5) and IL-13 during type 2 (allergic) inflammation in the lung. In Th2 cells, T cell receptor (TCR) signaling activates the transcription factors nuclear factor of activated T cells (NFAT), nuclear factor κB (NF-κB), and activator protein 1 (AP-1) to induce type 2 cytokines. ILC2s lack a TCR and respond instead to locally produced cytokines such as IL-33. Although IL-33 induces AP-1 and NF-κB, NFAT signaling has not been described in ILC2s. In this study, we report a nonredundant NFAT-dependent role for lipid-derived leukotrienes (LTs) in the activation of lung ILC2s. Using cytokine reporter and LT-deficient mice, we find that complete disruption of LT signaling markedly diminishes ILC2 activation and downstream responses during type 2 inflammation. Type 2 responses are equivalently attenuated in IL-33- and LT-deficient mice, and optimal ILC2 activation reflects potent synergy between these pathways. These findings expand our understanding of ILC2 regulation and may have important implications for the treatment of airways disease
Stability of R parity in supersymmetric models extended by U(1)_{B-L}
We perform a study of the stability of R-parity-conserving vacua of a
constrained version of the minimal supersymmetric model with a gauged
U(1)_{B-L} which can conserve R-parity, using homotopy continuation to find all
the extrema of the tree-level potential, for which we also calculated the
one-loop corrections. While we find that a majority of the points in the
parameter space preserve R-parity, we find that a significant portion of points
which naively have phenomenologically acceptable vacua which conserve R-parity
actually have deeper vacua which break R-parity through sneutrino VEVs. We
investigate under what conditions the deeper R-parity-violating vacua appear.
We find that while previous exploratory work was broadly correct in some of its
qualitative conclusions, we disagree in detail.Comment: 22 pages, 4 figures (32 sub-figures
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