197 research outputs found
CONNOTATION, CURRENT SITUATION AND COUNTERMEASURES OF TEACHERS \u27 JOB BURNOUT ON TEACHING EFFICACY
Constraints on from LHC Data
In this study, we apply LHC data to constrain the extension of the Standard
Model by an anomaly-free gauge group; this model contains
a new gauge boson () and a scalar dark matter particle (). We recast a large number of LHC analyses from ATLAS and CMS of
multi-lepton final states. We find that for GeV GeV
the strongest constraint comes from a dedicated search in the
final state by the CMS collaboration; for larger masses, searches
for final states with three leptons plus missing are more sensitive.
Searches for final states with two leptons and missing , which are
sensitive to decays into dark matter particles, can only probe
regions of parameter space that are excluded by searches in the and
lepton channels. The combination of LHC data excludes values of mass
and coupling constant that can explain the deficit in for GeV
GeV. However, for much of this range the LHC bound
is weaker than the bound that can be derived from searches for trident events
in neutrino-nucleus scattering.Comment: 15 pages, 4 figure
Two Piggybacking Codes with Flexible Sub-Packetization to Achieve Lower Repair Bandwidth
As a special class of array codes, piggybacking codes are MDS codes
(i.e., any out of nodes can retrieve all data symbols) that can achieve
low repair bandwidth for single-node failure with low sub-packetization . In
this paper, we propose two new piggybacking codes that have lower repair
bandwidth than the existing piggybacking codes given the same parameters. Our
first piggybacking codes can support flexible sub-packetization with , where . We show that our first piggybacking codes have
lower repair bandwidth for any single-node failure than the existing
piggybacking codes when , and .
Moreover, we propose second piggybacking codes such that the sub-packetization
is a multiple of the number of parity nodes (i.e., ), by jointly
designing the piggyback function for data node repair and transformation
function for parity node repair. We show that the proposed second piggybacking
codes have lowest repair bandwidth for any single-node failure among all the
existing piggybacking codes for the evaluated parameters
and
Generalized Simple Regenerating Codes: Trading Sub-packetization and Fault Tolerance
Maximum distance separable (MDS) codes have the optimal trade-off between
storage efficiency and fault tolerance, which are widely used in distributed
storage systems. As typical non-MDS codes, simple regenerating codes (SRCs) can
achieve both smaller repair bandwidth and smaller repair locality than
traditional MDS codes in repairing single-node erasure.
In this paper, we propose {\em generalized simple regenerating codes} (GSRCs)
that can support much more parameters than that of SRCs. We show that there is
a trade-off between sub-packetization and fault tolerance in our GSRCs, and
SRCs achieve a special point of the trade-off of GSRCs. We show that the fault
tolerance of our GSRCs increases when the sub-packetization increases linearly.
We also show that our GSRCs can locally repair any singe-symbol erasure and any
single-node erasure, and the repair bandwidth of our GSRCs is smaller than that
of the existing related codes
- …