3,020 research outputs found
Improving the security of multiparty quantum secret sharing against Trojan horse attack
We analyzed the security of the multiparty quantum secret sharing (MQSS)
protocol recently proposed by Zhang, Li and Man [Phys. Rev. A \textbf{71},
044301 (2005)] and found that this protocol is secure for any other
eavesdropper except for the agent Bob who prepares the quantum signals as he
can attack the quantum communication with a Trojan horse. That is, Bob replaces
the single-photon signal with a multi-photon one and the other agent Charlie
cannot find this cheating as she does not measure the photons before they runs
back from the boss Alice, which reveals that this MQSS protocol is not secure
for Bob. Finally, we present a possible improvement of the MQSS protocol
security with two single-photon measurements and six unitary operations.Comment: 4 pages, 2 figures; The revised version of the paper published in
Phys. Rev. A 72, 044302 (2005). A bug is modified and an addendum is adde
Information Filtering on Coupled Social Networks
In this paper, based on the coupled social networks (CSN), we propose a
hybrid algorithm to nonlinearly integrate both social and behavior information
of online users. Filtering algorithm based on the coupled social networks,
which considers the effects of both social influence and personalized
preference. Experimental results on two real datasets, \emph{Epinions} and
\emph{Friendfeed}, show that hybrid pattern can not only provide more accurate
recommendations, but also can enlarge the recommendation coverage while
adopting global metric. Further empirical analyses demonstrate that the mutual
reinforcement and rich-club phenomenon can also be found in coupled social
networks where the identical individuals occupy the core position of the online
system. This work may shed some light on the in-depth understanding structure
and function of coupled social networks
Multipartite entanglement purification with quantum nondemolition detectors
We present a scheme for multipartite entanglement purification of quantum
systems in a Greenberger-Horne-Zeilinger state with quantum nondemolition
detectors (QNDs). This scheme does not require the controlled-not gates which
cannot be implemented perfectly with linear optical elements at present, but
QNDs based on cross-Kerr nonlinearities. It works with two steps, i.e., the
bit-flipping error correction and the phase-flipping error correction. These
two steps can be iterated perfectly with parity checks and simple single-photon
measurements. This scheme does not require the parties to possess sophisticated
single photon detectors. These features maybe make this scheme more efficient
and feasible than others in practical applications.Comment: 8 pages, 5 figure
Sequential Wnt Agonist then Antagonist Treatment Accelerates Tissue Repair and Minimizes Fibrosis
Tissue fibrosis compromises organ function and occurs as a potential
long-term outcome in response to acute tissue injuries. Currently, lack of
mechanistic understanding prevents effective prevention and treatment of the
progression from acute injury to fibrosis. Here, we combined quantitative
experimental studies with a mouse kidney injury model and a computational
approach to determine how the physiological consequences are determined by the
severity of ischemia injury, and to identify how to manipulate Wnt signaling to
accelerate repair of ischemic tissue damage while minimizing fibrosis. The
study reveals that Wnt-mediated memory of prior injury contributes to fibrosis
progression, and ischemic preconditioning reduces the risk of death but
increases the risk of fibrosis. Furthermore, we validated the prediction that
sequential combination therapy of initial treatment with a Wnt agonist followed
by treatment with a Wnt antagonist can reduce both the risk of death and
fibrosis in response to acute injuries
Exploring the potentiality of standard sirens to probe cosmic opacity at high redshifts
In this work, using the Gaussian process, we explore the potentiality of
future gravitational wave (GW) measurements to probe cosmic opacity at high
redshifts through comparing its opacity-free luminosity distance (LD) with the
opacity-dependent one from the combination of Type Ia supernovae (SNIa) and
gamma-ray bursts (GRBs). The GW data, SNIa and GRB data are simulated from the
measurements of the future Einstein Telescope, the actual Pantheon compilation
and the latest observation of GRBs compiled by L. Amati {\it et al},
respectively. A nonparametric method is proposed to probe the spatial
homogeneity of cosmic transparency at high redshift by comparing the LD
reconstructed from the GW data with
that reconstructed from the Pantheon and GRB data. In addition, the cosmic
opacity is tested by using the parametrization for the optical depth, and the
results show that the constraints on cosmic opacity are more stringent than the
previous ones. It shows that the future GW measurements may be used as an
important tool to probe the cosmic opacity in the high redshift region.Comment: 21pages, 3 figures accepted by EPJC. arXiv admin note: text overlap
with arXiv:1912.0232
Ask Question First for Enhancing Lifelong Language Learning
Lifelong language learning aims to stream learning NLP tasks while retaining
knowledge of previous tasks. Previous works based on the language model and
following data-free constraint approaches have explored formatting all data as
"begin token (\textit{B}) + context (\textit{C}) + question (\textit{Q}) +
answer (\textit{A})" for different tasks. However, they still suffer from
catastrophic forgetting and are exacerbated when the previous task's pseudo
data is insufficient for the following reasons: (1) The model has difficulty
generating task-corresponding pseudo data, and (2) \textit{A} is prone to error
when \textit{A} and \textit{C} are separated by \textit{Q} because the
information of the \textit{C} is diminished before generating \textit{A}.
Therefore, we propose the Ask Question First and Replay Question (AQF-RQ),
including a novel data format "\textit{BQCA}" and a new training task to train
pseudo questions of previous tasks. Experimental results demonstrate that
AQF-RQ makes it easier for the model to generate more pseudo data that match
corresponding tasks, and is more robust to both sufficient and insufficient
pseudo-data when the task boundary is both clear and unclear. AQF-RQ can
achieve only 0.36\% lower performance than multi-task learning.Comment: This paper has been accepted for publication at COLING 202
4,6-DinitroÂbenzene-1,3-diamine
The molÂecule of the title compound, C6H6N4O4, is almost planar, being stabilized by two intraÂmolecular N—H⋯O hydrogen bonds. Further N—H⋯O links lead to a sheet in the crystal structure
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