collaborators

10 papers

cs.CV2025

Taming Diffusion Models for Image Restoration: A Review

Ziwei Luo, Fredrik K. Gustafsson, Zheng Zhao +2

Diffusion models have achieved remarkable progress in generative modelling, particularly in enhancing image quality to conform to human preferences. Recently, these models have als…

cs.LG2025

ESS-Flow: Training-free guidance of flow-based models as inference in source space

Adhithyan Kalaivanan, Zheng Zhao, Jens Sjölund +1

Guiding pretrained flow-based generative models for conditional generation or to produce samples with desired target properties enables solving diverse tasks without retraining on…

stat.ML2025

Conditioning diffusion models by explicit forward-backward bridging

Adrien Corenflos, Zheng Zhao, Simo Särkkä +2

Given an unconditional diffusion model targeting a joint model , using it to perform conditional simulation is still largely an open question and is typica…

stat.ML2025

Conditional sampling within generative diffusion models

Zheng Zhao, Ziwei Luo, Jens Sjölund +1

Generative diffusions are a powerful class of Monte Carlo samplers that leverage bridging Markov processes to approximate complex, high-dimensional distributions, such as those fou…

cs.LG2025

Entropy-regularized Diffusion Policy with Q-Ensembles for Offline Reinforcement Learning

Ruoqi Zhang, Ziwei Luo, Jens Sjölund +2

This paper presents advanced techniques of training diffusion policies for offline reinforcement learning (RL). At the core is a mean-reverting stochastic differential equation (SD…

cs.LG2024

Learning incomplete factorization preconditioners for GMRES

Paul Häusner, Aleix Nieto Juscafresa, Jens Sjölund

Incomplete LU factorizations of sparse matrices are widely used as preconditioners in Krylov subspace methods to speed up solving linear systems. Unfortunately, computing the preco…