activity
20182025
most citedDeepFlame: A deep learning empowered open-source platform for reacting flow simulations

70 citations · 164 across the 35 of their papers we have counts for

collaborators

35 papers

cs.LG2025

Probability Signature: Bridging Data Semantics and Embedding Structure in Language Models

Junjie Yao, Zhi-Qin John Xu

The embedding space of language models is widely believed to capture the semantic relationships; for instance, embeddings of digits often exhibit an ordered structure that correspo…

cs.LG2025

An overview of condensation phenomenon in deep learning

Zhi-Qin John Xu, Yaoyu Zhang, Zhangchen Zhou

In this paper, we provide an overview of a common phenomenon, condensation, observed during the nonlinear training of neural networks: During the nonlinear training of neural netwo…

cs.CL2025

Reasoning Bias of Next Token Prediction Training

Pengxiao Lin, Zhongwang Zhang, Zhi-Qin John Xu

Since the inception of Large Language Models (LLMs), the quest to efficiently train them for superior reasoning capabilities has been a pivotal challenge. The dominant training par…

cs.CL2025

An Analysis for Reasoning Bias of Language Models with Small Initialization

Junjie Yao, Zhongwang Zhang, Zhi-Qin John Xu

Transformer-based Large Language Models (LLMs) have revolutionized Natural Language Processing by demonstrating exceptional performance across diverse tasks. This study investigate…

math.NA2025

On understanding and overcoming spectral biases of deep neural network learning methods for solving PDEs

Zhi-Qin John Xu, Lulu Zhang, Wei Cai

In this review, we survey the latest approaches and techniques developed to overcome the spectral bias towards low frequency of deep neural network learning methods in learning mul…

cs.LG2024

A rationale from frequency perspective for grokking in training neural network

Zhangchen Zhou, Yaoyu Zhang, Zhi-Qin John Xu

Grokking is the phenomenon where neural networks NNs initially fit the training data and later generalize to the test data during training. In this paper, we empirically provide a…

cs.LG2024

Loss Jump During Loss Switch in Solving PDEs with Neural Networks

Zhiwei Wang, Lulu Zhang, Zhongwang Zhang +1

Using neural networks to solve partial differential equations (PDEs) is gaining popularity as an alternative approach in the scientific computing community. Neural networks can int…

cs.AI2024★ 2 cited

Understanding the Language Model to Solve the Symbolic Multi-Step Reasoning Problem from the Perspective of Buffer Mechanism

Zhiwei Wang, Yunji Wang, Zhongwang Zhang +7

Large language models have consistently struggled with complex reasoning tasks, such as mathematical problem-solving. Investigating the internal reasoning mechanisms of these model…

cs.LG2024★ 1 cited

Initialization is Critical to Whether Transformers Fit Composite Functions by Reasoning or Memorizing

Zhongwang Zhang, Pengxiao Lin, Zhiwei Wang +2

Transformers have shown impressive capabilities across various tasks, but their performance on compositional problems remains a topic of debate. In this work, we investigate the me…

math.DS2024

Input gradient annealing neural network for solving low-temperature Fokker-Planck equations

Liangkai Hang, Dan Hu, Zhi-Qin John Xu

We present a novel yet simple deep learning approach, called input gradient annealing neural network (IGANN), for solving stationary Fokker-Planck equations. Traditional methods, s…

cs.LG2024

Understanding Time Series Anomaly State Detection through One-Class Classification

Hanxu Zhou, Yuan Zhang, Guangjie Leng +2

For a long time, research on time series anomaly detection has mainly focused on finding outliers within a given time series. Admittedly, this is consistent with some practical pro…

cs.CL2024

Anchor function: a type of benchmark functions for studying language models

Zhongwang Zhang, Zhiwei Wang, Junjie Yao +4

Understanding transformer-based language models is becoming increasingly crucial, particularly as they play pivotal roles in advancing towards artificial general intelligence. Howe…

math.NA2024★ 4 cited

Solving multiscale dynamical systems by deep learning

Junjie Yao, Yuxiao Yi, Liangkai Hang +5

Multiscale dynamical systems, modeled by high-dimensional stiff ordinary differential equations (ODEs) with wide-ranging characteristic timescales, arise across diverse fields of s…

math.NA2023

An Unsupervised Deep Learning Approach for the Wave Equation Inverse Problem

Xiong-Bin Yan, Keke Wu, Zhi-Qin John Xu +1

Full-waveform inversion (FWI) is a powerful geophysical imaging technique that infers high-resolution subsurface physical parameters by solving a non-convex optimization problem. H…

cs.LG2023

Optimistic Estimate Uncovers the Potential of Nonlinear Models

Yaoyu Zhang, Zhongwang Zhang, Leyang Zhang +3

We propose an optimistic estimate to evaluate the best possible fitting performance of nonlinear models. It yields an optimistic sample size that quantifies the smallest possible s…

cs.LG2023★ 1 cited

Stochastic Modified Equations and Dynamics of Dropout Algorithm

Zhongwang Zhang, Yuqing Li, Tao Luo +1

Dropout is a widely utilized regularization technique in the training of neural networks, nevertheless, its underlying mechanism and its impact on achieving good generalization abi…

cs.LG2023★ 1 cited

Loss Spike in Training Neural Networks

Xiaolong Li, Zhi-Qin John Xu, Zhongwang Zhang

In this work, we investigate the mechanism underlying loss spikes observed during neural network training. When the training enters a region with a lower-loss-as-sharper (LLAS) str…

cs.LG2023★ 1 cited

Phase Diagram of Initial Condensation for Two-layer Neural Networks

Zhengan Chen, Yuqing Li, Tao Luo +2

The phenomenon of distinct behaviors exhibited by neural networks under varying scales of initialization remains an enigma in deep learning research. In this paper, based on the ea…

math.NA2022

Bayesian Inversion with Neural Operator (BINO) for Modeling Subdiffusion: Forward and Inverse Problems

Xiong-bin Yan, Zhi-Qin John Xu, Zheng Ma

Fractional diffusion equations have been an effective tool for modeling anomalous diffusion in complicated systems. However, traditional numerical methods require expensive computa…

cs.LG2022★ 1 cited

Linear Stability Hypothesis and Rank Stratification for Nonlinear Models

Yaoyu Zhang, Zhongwang Zhang, Leyang Zhang +3

Models with nonlinear architectures/parameterizations such as deep neural networks (DNNs) are well known for their mysteriously good generalization performance at overparameterizat…

physics.flu-dyn2022★ 70 cited

DeepFlame: A deep learning empowered open-source platform for reacting flow simulations

Runze Mao, Minqi Lin, Yan Zhang +3

In this work, we introduce DeepFlame, an open-source C++ platform with the capabilities of utilising machine learning algorithms and pre-trained models to solve for reactive flows.…

cs.LG2022★ 1 cited

Embedding Principle in Depth for the Loss Landscape Analysis of Deep Neural Networks

Zhiwei Bai, Tao Luo, Zhi-Qin John Xu +1

Understanding the relation between deep and shallow neural networks is extremely important for the theoretical study of deep learning. In this work, we discover an embedding princi…

cs.LG2022

An Experimental Comparison Between Temporal Difference and Residual Gradient with Neural Network Approximation

Shuyu Yin, Tao Luo, Peilin Liu +1

Gradient descent or its variants are popular in training neural networks. However, in deep Q-learning with neural network approximation, a type of reinforcement learning, gradient…

cs.LG2022

Limitation of Characterizing Implicit Regularization by Data-independent Functions

Leyang Zhang, Zhi-Qin John Xu, Tao Luo +1

In recent years, understanding the implicit regularization of neural networks (NNs) has become a central task in deep learning theory. However, implicit regularization is itself no…