2,738 research outputs found
Unconventional Superconducting Symmetry in a Checkerboard Antiferromagnet
We use a renormalized mean field theory to study the Gutzwiller projected BCS
states of the extended Hubbard model in the large limit, or the
--- model on a two-dimensional checkerboard lattice. At small
, the frustration due to the diagonal terms of and does not
alter the -wave pairing symmetry, and the negative (positive)
enhances (suppresses) the pairing order parameter. At large , the
ground state has an extended s-wave symmetry. At the intermediate , the
ground state is or -wave with time reversal symmetry broken.Comment: 6 pages, 6 figure
Off-policy Maximum Entropy Deep Reinforcement Learning Algorithm Based on RandomlyWeighted Triple Q -Learning
Reinforcement learning is an important branch of machine learning.With the development of deep learning,deep reinforcement learning research has gradually developed into the focus of reinforcement learning research.Model-free off-policy deep reinforcement learning algorithms for continuous control attract everyone’s attention because of their strong practicality.Like Q-learning,algorithms based on actor-critic suffer from the problem of overestimations.To a certain extent,clipped double Q-lear-ning method solves the effect of the overestimation in actor-critic algorithms,but it also introduces underestimation to the lear-ning process.In order to further solve the problems of overestimation and underestimation in the actor-critic algorithms,a new learning method,randomly weighted triple Q-learning method is proposed.In addition,combining the new method with the soft actor critic algorithm,a new soft actor critic algorithm based on randomly weighted triple Q-learning is proposed.This algorithm not only limits the Q estimation value near the real Q value,but also increases the randomness of the Q estimation value through randomly weighted method,so as to solve the problems of overestimation and underestimation of action value in the learning process.Experiment results show that,compared to the SAC algorithm and other currently popular deep reinforcement learning algorithms such as DDPG,PPO and TD3,the SAC-RWTQ algorithm has better performance on several Mujoco tasks on the gym simulation platform
Information Theory of Blockchain Systems
In this paper, we apply the information theory to provide an approximate
expression of the steady-state probability distribution for blockchain systems.
We achieve this goal by maximizing an entropy function subject to specific
constraints. These constraints are based on some prior information, including
the average numbers of transactions in the block and the transaction pool,
respectively. Furthermore, we use some numerical experiments to analyze how the
key factors in this approximate expression depend on the crucial parameters of
the blockchain system. As a result, this approximate expression has important
theoretical significance in promoting practical applications of blockchain
technology. At the same time, not only do the method and results given in this
paper provide a new line in the study of blockchain queueing systems, but they
also provide the theoretical basis and technical support for how to apply the
information theory to the investigation of blockchain queueing networks and
stochastic models more broadly.Comment: 14 pages, 5 figure
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