9,752 research outputs found
Deep Learning as a Parton Shower
We make the connection between certain deep learning architectures and the
renormalisation group explicit in the context of QCD by using a deep learning
network to construct a toy parton shower model. The model aims to describe
proton-proton collisions at the Large Hadron Collider. A convolutional
autoencoder learns a set of kernels that efficiently encode the behaviour of
fully showered QCD collision events. The network is structured recursively so
as to ensure self-similarity, and the number of trained network parameters is
low. Randomness is introduced via a novel custom masking layer, which also
preserves existing parton splittings by using layer-skipping connections. By
applying a shower merging procedure, the network can be evaluated on unshowered
events produced by a matrix element calculation. The trained network behaves as
a parton shower that qualitatively reproduces jet-based observables.Comment: 26 pages, 13 figure
The Kinetic Energy of Hydrocarbons as a Function of Electron Density and Convolutional Neural Networks
We demonstrate a convolutional neural network trained to reproduce the
Kohn-Sham kinetic energy of hydrocarbons from electron density. The output of
the network is used as a non-local correction to the conventional local and
semi-local kinetic functionals. We show that this approximation qualitatively
reproduces Kohn-Sham potential energy surfaces when used with conventional
exchange correlation functionals. Numerical noise inherited from the
non-linearity of the neural network is identified as the major challenge for
the model. Finally we examine the features in the density learned by the neural
network to anticipate the prospects of generalizing these models
Modulating Image Restoration with Continual Levels via Adaptive Feature Modification Layers
In image restoration tasks, like denoising and super resolution, continual
modulation of restoration levels is of great importance for real-world
applications, but has failed most of existing deep learning based image
restoration methods. Learning from discrete and fixed restoration levels, deep
models cannot be easily generalized to data of continuous and unseen levels.
This topic is rarely touched in literature, due to the difficulty of modulating
well-trained models with certain hyper-parameters. We make a step forward by
proposing a unified CNN framework that consists of few additional parameters
than a single-level model yet could handle arbitrary restoration levels between
a start and an end level. The additional module, namely AdaFM layer, performs
channel-wise feature modification, and can adapt a model to another restoration
level with high accuracy. By simply tweaking an interpolation coefficient, the
intermediate model - AdaFM-Net could generate smooth and continuous restoration
effects without artifacts. Extensive experiments on three image restoration
tasks demonstrate the effectiveness of both model training and modulation
testing. Besides, we carefully investigate the properties of AdaFM layers,
providing a detailed guidance on the usage of the proposed method.Comment: Accepted by CVPR 2019 (oral); code is available:
https://github.com/hejingwenhejingwen/AdaF
- …