1,596 research outputs found
What measurements of neutrino neutral current events can reveal
We show that neutral current (NC) measurements at neutrino detectors can play
a valuable role in the search for new physics. Such measurements have certain
intrinsic features and advantages that can fruitfully be combined with the
usual well-studied charged lepton detection channels in order to probe the
presence of new interactions or new light states. In addition to the fact that
NC events are immune to uncertainties in standard model neutrino mixing and
mass parameters, they can have small matter effects and superior rates since
all three flavours participate. We also show, as a general feature, that NC
measurements provide access to different combinations of CP phases and mixing
parameters compared to CC measurements at both long and short baseline
experiments. Using the Deep Underground Neutrino Experiment (DUNE) as an
illustrative setting, we demonstrate the capability of NC measurements to break
degeneracies arising in CC measurements, allowing us, in principle, to
distinguish between new physics that violates three flavour unitarity and that
which does not. Finally, we show that NC measurements can enable us to restrict
new physics parameters that are not easily constrained by CC measurements.Comment: 22 pages, 10 figure
User Constrained Thumbnail Generation using Adaptive Convolutions
Thumbnails are widely used all over the world as a preview for digital
images. In this work we propose a deep neural framework to generate thumbnails
of any size and aspect ratio, even for unseen values during training, with high
accuracy and precision. We use Global Context Aggregation (GCA) and a modified
Region Proposal Network (RPN) with adaptive convolutions to generate thumbnails
in real time. GCA is used to selectively attend and aggregate the global
context information from the entire image while the RPN is used to predict
candidate bounding boxes for the thumbnail image. Adaptive convolution
eliminates the problem of generating thumbnails of various aspect ratios by
using filter weights dynamically generated from the aspect ratio information.
The experimental results indicate the superior performance of the proposed
model over existing state-of-the-art techniques.Comment: International Conference on Acoustics, Speech, and Signal
Processing(ICASSP), 201
LSND and MiniBooNE as guideposts to understanding the muon results and the CDF II mass measurement
In recent times, several experiments have observed results that are in
significant conflict with the predictions of the Standard Model (SM). Two
neutrino experiments, LSND and MiniBooNE (MB) have reported electron-like
signal excesses above backgrounds. Both the Brookhaven and the Fermilab muon
collaborations have measured values of this parameter which, while
consistent with each other, are in conflict with the SM. Recently, the CDF II
collaboration has reported a precision measurement of the -boson mass that
is in strong conflict with the SM prediction. It is worthwhile to seek new
physics which may underly all four anomalies. In such a quest, the neutrino
experiments could play a crucial role, because once a common solution to these
anomalies is sought, LSND and MB, due to their highly restrictive requirements
and observed final states, help to greatly narrow the multiplicity of new
physics possibilities that are otherwise open to the mass and muon
discrepancies. Pursuant to this, earlier work has shown that LSND, MB and the
muon results can be understood in the context of a scalar extension of
the SM which incorporates a second Higgs doublet and a dark sector singlet. We
show that the same model leads to a contribution to the mass which is
consistent with the recent CDF II measurement. While the LSND, MB fits and the
muon results help determine the masses of the light scalars in the model,
the calculation of the oblique parameters and determines the allowed
mass ranges of the heavier pseudoscalar and the charged Higgs bosons as well as
the effective Weinberg angle and its new range.Comment: 11 pages, 8 figures, 1 table. Figues and related text added.
References adde
Adversarially Learned Abnormal Trajectory Classifier
We address the problem of abnormal event detection from trajectory data. In
this paper, a new adversarial approach is proposed for building a deep neural
network binary classifier, trained in an unsupervised fashion, that can
distinguish normal from abnormal trajectory-based events without the need for
setting manual detection threshold. Inspired by the generative adversarial
network (GAN) framework, our GAN version is a discriminative one in which the
discriminator is trained to distinguish normal and abnormal trajectory
reconstruction errors given by a deep autoencoder. With urban traffic videos
and their associated trajectories, our proposed method gives the best accuracy
for abnormal trajectory detection. In addition, our model can easily be
generalized for abnormal trajectory-based event detection and can still yield
the best behavioural detection results as demonstrated on the CAVIAR dataset.Comment: Accepted for the 16th Conference on Computer and Robot Vision (CRV)
201
A Comparative Analysis of Retrievability and PageRank Measures
The accessibility of documents within a collection holds a pivotal role in
Information Retrieval, signifying the ease of locating specific content in a
collection of documents. This accessibility can be achieved via two distinct
avenues. The first is through some retrieval model using a keyword or other
feature-based search, and the other is where a document can be navigated using
links associated with them, if available. Metrics such as PageRank, Hub, and
Authority illuminate the pathways through which documents can be discovered
within the network of content while the concept of Retrievability is used to
quantify the ease with which a document can be found by a retrieval model. In
this paper, we compare these two perspectives, PageRank and retrievability, as
they quantify the importance and discoverability of content in a corpus.
Through empirical experimentation on benchmark datasets, we demonstrate a
subtle similarity between retrievability and PageRank particularly
distinguishable for larger datasets.Comment: Accepted at FIRE 202
Deep learning for reconstructing protein structures from cryo-EM density maps: recent advances and future directions
Cryo-Electron Microscopy (cryo-EM) has emerged as a key technology to
determine the structure of proteins, particularly large protein complexes and
assemblies in recent years. A key challenge in cryo-EM data analysis is to
automatically reconstruct accurate protein structures from cryo-EM density
maps. In this review, we briefly overview various deep learning methods for
building protein structures from cryo-EM density maps, analyze their impact,
and discuss the challenges of preparing high-quality data sets for training
deep learning models. Looking into the future, more advanced deep learning
models of effectively integrating cryo-EM data with other sources of
complementary data such as protein sequences and AlphaFold-predicted structures
need to be developed to further advance the field
Predicting Next Local Appearance for Video Anomaly Detection
We present a local anomaly detection method in videos. As opposed to most
existing methods that are computationally expensive and are not very
generalizable across different video scenes, we propose an adversarial
framework that learns the temporal local appearance variations by predicting
the appearance of a normally behaving object in the next frame of a scene by
only relying on its current and past appearances. In the presence of an
abnormally behaving object, the reconstruction error between the real and the
predicted next appearance of that object indicates the likelihood of an
anomaly. Our method is competitive with the existing state-of-the-art while
being significantly faster for both training and inference and being better at
generalizing to unseen video scenes.Comment: Accepted as an oral presentation for MVA'202
- …