1,409 research outputs found
Efficient multipartite entanglement purification with non-identical states
We present an efficient and general multipartite entanglement purification
protocol (MEPP) for N-photon systems in Greenberger-Horne-Zeilinger (GHZ)
states with non-identical input states. As a branch of entanglement
purification, besides the cases of successful purification, the recurrence MEPP
actually has the reusable discarded items which are usually regarded as a
failure. Our protocol contains two parts for bit-flip error correction. The
first one is the conventional MEPP, corresponding successful cases. The second
one includes two efficient approaches, recycling purification with entanglement
link and direct residual entanglement purification, that can utilize discarded
items. We also make a comparison between two approaches. Which method to use
depends on initial input states, and in most cases the approach of direct
residual purification is optimal for it not only may obtain a higher fidelity
entangled state but also it does not require additional sophisticated links. In
addition, for phase-flip errors, the discarded items still have available
residual entanglement in the case of different input states. With these
approaches, this MEPP has a higher efficiency than all previous MEPPs and it
may have potential applications in the future long-distance quantum
communications and networks.Comment: 20 pages,12 figure
Modeling Dynamic Heterogeneous Graph and Node Importance for Future Citation Prediction
Accurate citation count prediction of newly published papers could help
editors and readers rapidly figure out the influential papers in the future.
Though many approaches are proposed to predict a paper's future citation, most
ignore the dynamic heterogeneous graph structure or node importance in academic
networks. To cope with this problem, we propose a Dynamic heterogeneous Graph
and Node Importance network (DGNI) learning framework, which fully leverages
the dynamic heterogeneous graph and node importance information to predict
future citation trends of newly published papers. First, a dynamic
heterogeneous network embedding module is provided to capture the dynamic
evolutionary trends of the whole academic network. Then, a node importance
embedding module is proposed to capture the global consistency relationship to
figure out each paper's node importance. Finally, the dynamic evolutionary
trend embeddings and node importance embeddings calculated above are combined
to jointly predict the future citation counts of each paper, by a log-normal
distribution model according to multi-faced paper node representations.
Extensive experiments on two large-scale datasets demonstrate that our model
significantly improves all indicators compared to the SOTA models.Comment: Accepted by CIKM'202
Suppression of Laccase 2 severely impairs cuticle tanning and pathogen resistance during the pupal metamorphosis of Anopheles sinensis (Diptera: Culicidae)
Amino acid sequence identity of Cu-oxidase domains of LAC2 orthologs. (PDF 109 kb
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H Time Lags and Implications for Super-Eddington Accretion
We have completed two years of photometric and spectroscopic monitoring of a
large number of active galactic nuclei (AGNs) with very high accretion rates.
In this paper, we report on the result of the second phase of the campaign,
during 2013--2014, and the measurements of five new H time lags out of
eight monitored AGNs. All five objects were identified as super-Eddington
accreting massive black holes (SEAMBHs). The highest measured accretion rates
for the objects in this campaign are , where
,
is the mass accretion rates, is the Eddington luminosity and
is the speed of light. We find that the H time lags in SEAMBHs are
significantly shorter than those measured in sub-Eddington AGNs, and the
deviations increase with increasing accretion rates. Thus, the relationship
between broad-line region size () and optical luminosity at
5100\AA, , requires accretion rate as an additional
parameter. We propose that much of the effect may be due to the strong
anisotropy of the emitted slim-disk radiation. Scaling by
the gravitational radius of the black hole, we define a new radius-mass
parameter () and show that it saturates at a critical accretion rate of
, indicating a transition from thin to slim
accretion disk and a saturated luminosity of the slim disks. The parameter
is a very useful probe for understanding the various types of accretion onto
massive black holes. We briefly comment on implications to the general
population of super-Eddington AGNs in the universe and applications to
cosmology.Comment: 53 pages, 12 figures, 7 tables, accepted for publication in The
Astrophysical Journa
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