195 research outputs found
A simple and natural interpretations of the DAMPE cosmic-ray electron/positron spectrum within two sigma deviations
The DArk Matter Particle Explorer (DAMPE) experiment has recently announced
the first results for the measurement of total electron plus positron fluxes
between 25 GeV and 4.6 TeV. A spectral break at about 0.9 TeV and a tentative
peak excess around 1.4 TeV have been found. However, it is very difficult to
reproduce both the peak signal and the smooth background including spectral
break simultaneously. We point out that the numbers of events in the two energy
ranges (bins) close to the 1.4 TeV excess have deficits. With the
basic physics principles such as simplicity and naturalness, we consider the
, , and deviations due to statistical
fluctuations for the 1229.3~GeV bin, 1411.4~GeV bin, and 1620.5~GeV bin.
Interestingly, we show that all the DAMPE data can be explained consistently
via both the continuous distributed pulsar and dark matter interpretations,
which have and (for all the 38
points in DAMPE electron/positron spectrum with 3 of them revised),
respectively. These results are different from the previous analyses by
neglecting the 1.4 TeV excess. At the same time, we do a similar global fitting
on the newly released CALET lepton data, which could also be interpreted by
such configurations. Moreover, we present a dark matter model with
Breit-Wigner mechanism, which can provide the proper dark matter annihilation
cross section and escape the CMB constraint. Furthermore, we suggest a few ways
to test our proposal.Comment: 18 pages, 6 figures, 5 tables. Figures and Bibs update
The Application of Two-level Attention Models in Deep Convolutional Neural Network for Fine-grained Image Classification
Fine-grained classification is challenging because categories can only be
discriminated by subtle and local differences. Variances in the pose, scale or
rotation usually make the problem more difficult. Most fine-grained
classification systems follow the pipeline of finding foreground object or
object parts (where) to extract discriminative features (what).
In this paper, we propose to apply visual attention to fine-grained
classification task using deep neural network. Our pipeline integrates three
types of attention: the bottom-up attention that propose candidate patches, the
object-level top-down attention that selects relevant patches to a certain
object, and the part-level top-down attention that localizes discriminative
parts. We combine these attentions to train domain-specific deep nets, then use
it to improve both the what and where aspects. Importantly, we avoid using
expensive annotations like bounding box or part information from end-to-end.
The weak supervision constraint makes our work easier to generalize.
We have verified the effectiveness of the method on the subsets of ILSVRC2012
dataset and CUB200_2011 dataset. Our pipeline delivered significant
improvements and achieved the best accuracy under the weakest supervision
condition. The performance is competitive against other methods that rely on
additional annotations
Fine-grained Discriminative Localization via Saliency-guided Faster R-CNN
Discriminative localization is essential for fine-grained image
classification task, which devotes to recognizing hundreds of subcategories in
the same basic-level category. Reflecting on discriminative regions of objects,
key differences among different subcategories are subtle and local. Existing
methods generally adopt a two-stage learning framework: The first stage is to
localize the discriminative regions of objects, and the second is to encode the
discriminative features for training classifiers. However, these methods
generally have two limitations: (1) Separation of the two-stage learning is
time-consuming. (2) Dependence on object and parts annotations for
discriminative localization learning leads to heavily labor-consuming labeling.
It is highly challenging to address these two important limitations
simultaneously. Existing methods only focus on one of them. Therefore, this
paper proposes the discriminative localization approach via saliency-guided
Faster R-CNN to address the above two limitations at the same time, and our
main novelties and advantages are: (1) End-to-end network based on Faster R-CNN
is designed to simultaneously localize discriminative regions and encode
discriminative features, which accelerates classification speed. (2)
Saliency-guided localization learning is proposed to localize the
discriminative region automatically, avoiding labor-consuming labeling. Both
are jointly employed to simultaneously accelerate classification speed and
eliminate dependence on object and parts annotations. Comparing with the
state-of-the-art methods on the widely-used CUB-200-2011 dataset, our approach
achieves both the best classification accuracy and efficiency.Comment: 9 pages, to appear in ACM MM 201
Element Recognition and Innovation Transformation of Cultural and Creative Products: Based on Eye Movement Experiment
This paper analyzes tourists’ perceived preferences for cultural and creative product elements using human-computer interaction technology and constructs the innovation and transformation path of cultural and creative products from four dimensions: concept, elements, content, and structure. The Great Wall tourism cultural and creative products are used as an example. The findings demonstrate that: (1) From a behavioral data viewpoint, cultural and creative items’ overall inventiveness, formal design, manufacturing method, area, cultural collection value, and function have varying degrees of influence on visitors’ perceived preferences; (2) The richness and attraction of character expression, action, and form components from the hotspot map and matrix map can boost the visual engagement impact of visitors. Scenic area architecture may enhance visitors’ immersion experiences of local culture since it serves as the design prototype for cultural and creative businesses. (3) The number of fixation points, total fixation time, and saccade frequency of cultural and creative products with various design elements differ significantly when viewed from the perspective of the eye movement index, and these differences are further presented as individualized tourist behavior characteristics. (4) From a design standpoint, it is essential that the circumstances of the product satisfy the needs of visitors in order to produce high-quality cultural and creative products. Innovative ideas should be used to steer the innovation and transformation of cultural and creative products, enhancing the universal design of products with element innovation, enhancing the cultural legacies of products with content innovation, and lengthening the market cycle of products with structural innovation. The use of modern technology broadens the research methodologies for the tourism field and creates new research environments for tourism experimentation
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