6,902 research outputs found
Traveling wave solutions for a discrete diffusive epidemic model
[[abstract]]We study the traveling wave solutions for a discrete diffusive
epidemic model. The traveling wave is a mixed of front and pulse types.
We derive the existence and non-existence of traveling wave solutions of
this model. The proof of existence is based on constructing a suitable
pair of upper and lower solutions and the application of Schauder’s fixed
point theorem. By passing to the limit for a sequence of truncated
problems, we are able to derive the existence of traveling waves by a
delicate analysis of wave tails. Some open problems are also addressed.[[notice]]補æ£å®Œ
General Framework of Reversible Watermarking Based on Asymmetric Histogram Shifting of Prediction Error
This paper presents a general framework for the reversible watermarking based on asymmetric histogram shifting of prediction error, which is inspired by reversible watermarking of prediction error. Different from the conventional algorithms using single-prediction scheme to create symmetric histogram, the proposed method employs a multi-prediction scheme, which calculates multiple prediction values for the pixels. Then, the suitable value would be selected by two dual asymmetric selection functions to construct two asymmetric error histograms. Finally, the watermark is embedded in the two error histograms separately utilizing a complementary embedding strategy. The proposed framework provides a new perspective for the research of reversible watermarking, which brings about many benefits for the information security
Efficient polarization entanglement purification based on parametric down-conversion sources with cross-Kerr nonlinearity
We present a way for entanglement purification based on two parametric
down-conversion (PDC) sources with cross-Kerr nonlinearities. It is comprised
of two processes. The first one is a primary entanglement purification protocol
for PDC sources with nondestructive quantum nondemolition (QND) detectors by
transferring the spatial entanglement of photon pairs to their polarization. In
this time, the QND detectors act as the role of controlled-not (CNot) gates.
Also they can distinguish the photon number of the spatial modes, which
provides a good way for the next process to purify the entanglement of the
photon pairs kept more. In the second process for entanglement purification,
new QND detectors are designed to act as the role of CNot gates. This protocol
has the advantage of high yield and it requires neither CNot gates based on
linear optical elements nor sophisticated single-photon detectors, which makes
it more convenient in practical applications.Comment: 8 pages, 7 figure
View suggestion for interactive segmentation of indoor scenes
Point cloud segmentation is a fundamental problem. Due to the complexity of real-world scenes and the limitations of 3D scanners, interactive segmentation is currently the only way to cope with all kinds of point clouds. However, interactively segmenting complex and large-scale scenes is very time-consuming. In this paper, we present a novel interactive system for segmenting point cloud scenes. Our system automatically suggests a series of camera views, in which users can conveniently specify segmentation guidance. In this way, users may focus on specifying segmentation hints instead of manually searching for desirable views of unsegmented objects, thus significantly reducing user effort. To achieve this, we introduce a novel view preference model, which is based on a set of dedicated view attributes, with weights learned from a user study. We also introduce support relations for both graph-cut-based segmentation and finding similar objects. Our experiments show that our segmentation technique helps users quickly segment various types of scenes, outperforming alternative methods
HoMM: Higher-order Moment Matching for Unsupervised Domain Adaptation
Minimizing the discrepancy of feature distributions between different domains
is one of the most promising directions in unsupervised domain adaptation. From
the perspective of distribution matching, most existing discrepancy-based
methods are designed to match the second-order or lower statistics, which
however, have limited expression of statistical characteristic for non-Gaussian
distributions. In this work, we explore the benefits of using higher-order
statistics (mainly refer to third-order and fourth-order statistics) for domain
matching. We propose a Higher-order Moment Matching (HoMM) method, and further
extend the HoMM into reproducing kernel Hilbert spaces (RKHS). In particular,
our proposed HoMM can perform arbitrary-order moment tensor matching, we show
that the first-order HoMM is equivalent to Maximum Mean Discrepancy (MMD) and
the second-order HoMM is equivalent to Correlation Alignment (CORAL). Moreover,
the third-order and the fourth-order moment tensor matching are expected to
perform comprehensive domain alignment as higher-order statistics can
approximate more complex, non-Gaussian distributions. Besides, we also exploit
the pseudo-labeled target samples to learn discriminative representations in
the target domain, which further improves the transfer performance. Extensive
experiments are conducted, showing that our proposed HoMM consistently
outperforms the existing moment matching methods by a large margin. Codes are
available at \url{https://github.com/chenchao666/HoMM-Master}Comment: Accept by AAAI-2020, codes are available at
https://github.com/chenchao666/HoMM-Maste
Rapid Amygdala Kindling Causes Motor Seizure and Comorbidity of Anxiety- and Depression-Like Behaviors in Rats
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