Search Results for author: Yufei Zhang

Found 23 papers, 2 papers with code

UniDCP: Unifying Multiple Medical Vision-language Tasks via Dynamic Cross-modal Learnable Prompts

no code implementations18 Dec 2023 Chenlu Zhan, Yufei Zhang, Yu Lin, Gaoang Wang, Hongwei Wang

Medical vision-language pre-training (Med-VLP) models have recently accelerated the fast-growing medical diagnostics application.

Language Modelling

A Fisher-Rao gradient flow for entropy-regularised Markov decision processes in Polish spaces

no code implementations4 Oct 2023 Bekzhan Kerimkulov, James-Michael Leahy, David Siska, Lukasz Szpruch, Yufei Zhang

We study the global convergence of a Fisher-Rao policy gradient flow for infinite-horizon entropy-regularised Markov decision processes with Polish state and action space.

LEMMA

An Offline Learning Approach to Propagator Models

no code implementations6 Sep 2023 Eyal Neuman, Wolfgang Stockinger, Yufei Zhang

We show that a trader who tries to minimise her execution costs by using a greedy strategy purely based on the estimated propagator will encounter suboptimality due to so-called spurious correlation between the trading strategy and the estimator and due to intrinsic uncertainty resulting from a biased cost functional.

Body Knowledge and Uncertainty Modeling for Monocular 3D Human Body Reconstruction

no code implementations ICCV 2023 Yufei Zhang, Hanjing Wang, Jeffrey O. Kephart, Qiang Ji

While 3D body reconstruction methods have made remarkable progress recently, it remains difficult to acquire the sufficiently accurate and numerous 3D supervisions required for training.

3D Reconstruction

A Neural RDE approach for continuous-time non-Markovian stochastic control problems

no code implementations25 Jun 2023 Melker Hoglund, Emilio Ferrucci, Camilo Hernandez, Aitor Muguruza Gonzalez, Cristopher Salvi, Leandro Sanchez-Betancourt, Yufei Zhang

We propose a novel framework for solving continuous-time non-Markovian stochastic control problems by means of neural rough differential equations (Neural RDEs) introduced in Morrill et al. (2021).

Statistical Learning with Sublinear Regret of Propagator Models

no code implementations12 Jan 2023 Eyal Neuman, Yufei Zhang

For the exploration phase we propose a novel approach for non-parametric estimation of the price impact kernel by observing only the visible price process and derive sharp bounds on the convergence rate, which are characterised by the singularity of the propagator.

Convergence of policy gradient methods for finite-horizon exploratory linear-quadratic control problems

no code implementations1 Nov 2022 Michael Giegrich, Christoph Reisinger, Yufei Zhang

We study the global linear convergence of policy gradient (PG) methods for finite-horizon continuous-time exploratory linear-quadratic control (LQC) problems.

Policy Gradient Methods

Decomposing User-APP Graph into Subgraphs for Effective APP and User Embedding Learning

no code implementations13 Oct 2022 Tan Yu, Jun Zhi, Yufei Zhang, Jian Li, Hongliang Fei, Ping Li

In this paper, we formulate the APP-installation user embedding learning into a bipartite graph embedding problem.

Graph Embedding Graph Learning

Optimal scheduling of entropy regulariser for continuous-time linear-quadratic reinforcement learning

no code implementations8 Aug 2022 Lukasz Szpruch, Tanut Treetanthiploet, Yufei Zhang

This work uses the entropy-regularised relaxed stochastic control perspective as a principled framework for designing reinforcement learning (RL) algorithms.

reinforcement-learning Reinforcement Learning (RL) +1

SolarGAN: Synthetic Annual Solar Irradiance Time Series on Urban Building Facades via Deep Generative Networks

no code implementations1 Jun 2022 Yufei Zhang, Arno Schlüter, Christoph Waibel

Building Integrated Photovoltaics (BIPV) is a promising technology to decarbonize urban energy systems via harnessing solar energy available on building envelopes.

Time Series Time Series Analysis

Linear convergence of a policy gradient method for some finite horizon continuous time control problems

no code implementations22 Mar 2022 Christoph Reisinger, Wolfgang Stockinger, Yufei Zhang

Despite its popularity in the reinforcement learning community, a provably convergent policy gradient method for continuous space-time control problems with nonlinear state dynamics has been elusive.

Policy Gradient Methods reinforcement-learning +1

Model Pruning Based on Quantified Similarity of Feature Maps

no code implementations13 May 2021 Zidu Wang, Xuexin Liu, Long Huang, Yunqing Chen, Yufei Zhang, Zhikang Lin, Rui Wang

In this paper, we propose a novel theory to find redundant information in three-dimensional tensors, namely Quantified Similarity between Feature Maps (QSFM), and utilize this theory to guide the filter pruning procedure.

Reinforcement learning for linear-convex models with jumps via stability analysis of feedback controls

no code implementations19 Apr 2021 Xin Guo, Anran Hu, Yufei Zhang

We study finite-time horizon continuous-time linear-convex reinforcement learning problems in an episodic setting.

Reinforcement Learning (RL)

Understanding Deep Architecture with Reasoning Layer

1 code implementation NeurIPS 2020 Xinshi Chen, Yufei Zhang, Christoph Reisinger, Le Song

Recently, there is a surge of interest in combining deep learning models with reasoning in order to handle more sophisticated learning tasks.

Learning the aerodynamic design of supercritical airfoils through deep reinforcement learning

no code implementations5 Oct 2020 Runze Li, Yufei Zhang, Haixin Chen

The policy is then trained in environments based on surrogate models, of which the mean drag reduction of 200 airfoils can be effectively improved by reinforcement learning.

Computational Engineering, Finance, and Science Data Analysis, Statistics and Probability

Logarithmic regret for episodic continuous-time linear-quadratic reinforcement learning over a finite-time horizon

no code implementations27 Jun 2020 Matteo Basei, Xin Guo, Anran Hu, Yufei Zhang

We study finite-time horizon continuous-time linear-quadratic reinforcement learning problems in an episodic setting, where both the state and control coefficients are unknown to the controller.

Reinforcement Learning (RL)

Understanding Deep Architectures with Reasoning Layer

1 code implementation24 Jun 2020 Xinshi Chen, Yufei Zhang, Christoph Reisinger, Le Song

Recently, there has been a surge of interest in combining deep learning models with reasoning in order to handle more sophisticated learning tasks.

Regularity and stability of feedback relaxed controls

no code implementations9 Jan 2020 Christoph Reisinger, Yufei Zhang

This paper proposes a relaxed control regularization with general exploration rewards to design robust feedback controls for multi-dimensional continuous-time stochastic exit time problems.

Decision Making

A neural network based policy iteration algorithm with global $H^2$-superlinear convergence for stochastic games on domains

no code implementations5 Jun 2019 Kazufumi Ito, Christoph Reisinger, Yufei Zhang

In this work, we propose a class of numerical schemes for solving semilinear Hamilton-Jacobi-Bellman-Isaacs (HJBI) boundary value problems which arise naturally from exit time problems of diffusion processes with controlled drift.

Rectified deep neural networks overcome the curse of dimensionality for nonsmooth value functions in zero-sum games of nonlinear stiff systems

no code implementations15 Mar 2019 Christoph Reisinger, Yufei Zhang

In this paper, we establish that for a wide class of controlled stochastic differential equations (SDEs) with stiff coefficients, the value functions of corresponding zero-sum games can be represented by a deep artificial neural network (DNN), whose complexity grows at most polynomially in both the dimension of the state equation and the reciprocal of the required accuracy.

Cannot find the paper you are looking for? You can Submit a new open access paper.