21,568 research outputs found
SUPERT: Towards New Frontiers in Unsupervised Evaluation Metrics for Multi-Document Summarization
We study unsupervised multi-document summarization evaluation metrics, which
require neither human-written reference summaries nor human annotations (e.g.
preferences, ratings, etc.). We propose SUPERT, which rates the quality of a
summary by measuring its semantic similarity with a pseudo reference summary,
i.e. selected salient sentences from the source documents, using contextualized
embeddings and soft token alignment techniques. Compared to the
state-of-the-art unsupervised evaluation metrics, SUPERT correlates better with
human ratings by 18-39%. Furthermore, we use SUPERT as rewards to guide a
neural-based reinforcement learning summarizer, yielding favorable performance
compared to the state-of-the-art unsupervised summarizers. All source code is
available at https://github.com/yg211/acl20-ref-free-eval.Comment: ACL 202
Social contagions on interdependent lattice networks
Although an increasing amount of research is being done on the dynamical processes on interdependent spatial networks, knowledge of how interdependent spatial networks influence the dynamics of social contagion in them is sparse. Here we present a novel non-Markovian social contagion model on interdependent spatial networks composed of two identical two-dimensional lattices. We compare the dynamics of social contagion on networks with different fractions of dependency links and find that the density of final recovered nodes increases as the number of dependency links is increased. We use a finite-size analysis method to identify the type of phase transition in the giant connected components (GCC) of the final adopted nodes and find that as we increase the fraction of dependency links, the phase transition switches from second-order to first-order. In strong interdependent spatial networks with abundant dependency links, increasing the fraction of initial adopted nodes can induce the switch from a first-order to second-order phase transition associated with social contagion dynamics. In networks with a small number of dependency links, the phase transition remains second-order. In addition, both the second-order and first-order phase transition points can be decreased by increasing the fraction of dependency links or the number of initially-adopted nodes.This work was partially supported by National Natural Science Foundation of China (Grant Nos 61501358, 61673085), and the Fundamental Research Funds for the Central Universities. (61501358 - National Natural Science Foundation of China; 61673085 - National Natural Science Foundation of China; Fundamental Research Funds for the Central Universities)Published versio
Phase transitions and thermodynamics of the two-dimensional Ising model on a distorted Kagom\'{e} lattice
The two-dimensional Ising model on a distorted Kagom\'{e} lattice is studied
by means of exact solutions and the tensor renormalisation group (TRG) method.
The zero-field phase diagrams are obtained, where three phases such as
ferromagnetic, ferrimagnetic and paramagnetic phases, along with the
second-order phase transitions, have been identified. The TRG results are quite
accurate and reliable in comparison to the exact solutions. In a magnetic
field, the magnetization (), susceptibility and specific heat are studied by
the TRG algorithm, where the plateaux are observed in the magnetization
curves for some couplings. The experimental data of susceptibility for the
complex Co(N)(bpg) DMF are fitted with the TRG results,
giving the couplings of the complex and
Parton Distributions from Boosted Fields in the Coulomb Gauge
We propose a new method to calculate parton distribution functions (PDFs)
from correlations of boosted quarks and gluons in the Coulomb gauge. Compared
to the widely used quasi-PDFs defined from gauge-invariant Wilson-line
operators, such correlations offer advantages including absence of linear power
divergence, enhanced long-range precision, and accessibility to larger off-axis
momenta. We verify the validity of this method at next-to-leading order in
perturbation theory and use it to calculate the pion valence quark PDF on a
lattice with spacing fm and valence pion mass MeV. Our
result agrees with that from the gauge-invariant quasi-PDF at similar
precision, achieved with only half the computational cost through a large
off-axis momentum GeV. This opens the door to a more
efficient way to calculate parton physics on the lattice.Comment: 5 pages, 4 figures, and the appendi
Microscopic Investigation of a Copper Molten Mark by Optical Microscopy (OM) and Atomic Force Microscopy (AFM)
AbstractA wide variety of physical and chemical detecting methods have been proposed for discriminating between and electric arc bead that caused a fire, versus one that was caused by the fire itself. The simplest proposed method claims that examination of the molten marks in a bead under a microscope will suffice to make the distinction. Generally, copper molten marks of the bead are examined by using optical (OM) and scanning electron microscopy (SEM). In this paper, OM and AFM were employed to investigate a molten mark formed in laboratory. AFM observation reveals that AFM could be an auxiliary method to investigate the copper molten mark formed in the fire in order to confirm the reasons of the fire
- …