964 research outputs found
A Descriptive Model of Robot Team and the Dynamic Evolution of Robot Team Cooperation
At present, the research on robot team cooperation is still in qualitative
analysis phase and lacks the description model that can quantitatively describe
the dynamical evolution of team cooperative relationships with constantly
changeable task demand in Multi-robot field. First this paper whole and static
describes organization model HWROM of robot team, then uses Markov course and
Bayesian theorem for reference, dynamical describes the team cooperative
relationships building. Finally from cooperative entity layer, ability layer
and relative layer we research team formation and cooperative mechanism, and
discuss how to optimize relative action sets during the evolution. The dynamic
evolution model of robot team and cooperative relationships between robot teams
proposed and described in this paper can not only generalize the robot team as
a whole, but also depict the dynamic evolving process quantitatively. Users can
also make the prediction of the cooperative relationship and the action of the
robot team encountering new demands based on this model. Journal web page & a
lot of robotic related papers www.ars-journal.co
The effective field theory approach to the strong coupling issue in gravity with a non-minimally coupled scalar field
The Hamiltonian analysis for gravity implies the existence of at least
one scalar-type degree of freedom (DoF). However, this scalar DoF of
gravity does not manifest in linear perturbations around a cosmological
background, which indicates an underlying strong coupling problem. In this work
we expand the scope by introducing an extra scalar field non-minimally coupled
to gravity, aiming to address or alleviate the aforementioned strong
coupling problem. Employing the effective field theory (EFT) approach, we
provide a class of torsional EFT forms up to second order operators, avoiding
the Ostrogradsky ghost. To illustrate this phenomenon, we study a simple model
and perform a detailed analysis of its linear scalar perturbations. The results
demonstrate that the coupling terms in this toy model are necessary to avoid
the initial degenerate situation. The complete avoidance of new constraints
requires more coupling terms. Once this vanishing scalar DoF starts propagating
in cosmological background at linear level, this phenomenon will demand a
revisit of the strong coupling issue that arises in gravity,
particularly in the presence of matter coupling
Giant negative magnetoresistance induced by the chiral anomaly in individual Cd3As2 nanowires
Cd3As2 is a newly booming Dirac semimetal with linear dispersion along all
three momentum directions and can be viewed as 3D analog of graphene. As
breaking of either time reversal symmetry or spatial inversion symmetry, the
Dirac semimetal is believed to transform into Weyl semimetal with exotic chiral
anomaly effect, while the experimental evidence of the chiral anomaly is still
missing in Cd3As2. Here we report the magneto-transport properties of
individual Cd3As2 nanowires. Large negative magnetoresistance (MR) with
magnitude of -63% at 60 K and -11% at 300 K are observed when the magnetic
field is parallel with the electric field direction, giving the evidence of the
chiral magnetic effect in Cd3As2 nanowires. In addition, the critical magnetic
field BC, where there is an extremum of the negative MR, increases with
increasing temperature. As the first observation of chiral anomaly induced
negative MR in Cd3As2 nanowires, it may offer valuable insights for low
dimensional physics in Dirac semimetals.Comment: 4 figure
NMDA receptor internalization down-regulates NMDA receptor-mediated synaptic responses through the inhibition of remaining (non-internalized) surface NMDA receptors
Cell-surface protein endocytosis is critically involved in the regulation of organismal homeostasis, immune responses, development and neurotransmission [1,2,3,4]. Mechanisms underlying the endocytosis of cell surface proteins have been extensively investigated. However, until very recently no study has reported how non-internalized cell surface proteins may behave following endocytosis of same type of proteins. Here, we highlight findings that regulated NMDA receptor (NMDAR) internalization not only reduces the amount of NMDARs expressed on neuronal surface but also through activating PKD1 pathway phosphorylates and down-regulates remaining (non-internalized) surface NMDARs. This down-regulation of remaining surface NMDARs plays a critical role in the modulation of NMDAR-mediated synaptic responses by NMDAR internalization
- …