no code implementations • 2 May 2023 • Aki Barry, Lei Han, Gianluca Demartini
By adding noise to the original datasets, we can explore the relationship between the quality of the training data and the fairness of the output of the models trained on that data.
1 code implementation • 15 Sep 2022 • Hao Sun, Lei Han, Rui Yang, Xiaoteng Ma, Jian Guo, Bolei Zhou
We validate our insight on a range of RL tasks and show its improvement over baselines: (1) In offline RL, the conservative exploitation leads to improved performance based on off-the-shelf algorithms; (2) In online continuous control, multiple value functions with different shifting constants can be used to tackle the exploration-exploitation dilemma for better sample efficiency; (3) In discrete control tasks, a negative reward shifting yields an improvement over the curiosity-based exploration method.
no code implementations • 13 Jun 2022 • Lei Han, Jiawei Xu, Cheng Zhou, Yizheng Zhang, Zhengyou Zhang
Then, integrating the two algorithms offers the complete algorithm Relative Policy-Transition Optimization (RPTO), in which the policy interacts with the two environments simultaneously, such that data collections from two environments, policy and transition updates are completed in one closed loop to form a principled learning framework for policy transfer.
1 code implementation • 6 Jun 2022 • Rui Yang, Chenjia Bai, Xiaoteng Ma, Zhaoran Wang, Chongjie Zhang, Lei Han
Offline reinforcement learning (RL) provides a promising direction to exploit massive amount of offline data for complex decision-making tasks.
1 code implementation • ICLR 2022 • Rui Yang, Yiming Lu, Wenzhe Li, Hao Sun, Meng Fang, Yali Du, Xiu Li, Lei Han, Chongjie Zhang
In this paper, we revisit the theoretical property of GCSL -- optimizing a lower bound of the goal reaching objective, and extend GCSL as a novel offline goal-conditioned RL algorithm.
1 code implementation • NeurIPS 2021 • Chenjia Bai, Lingxiao Wang, Lei Han, Animesh Garg, Jianye Hao, Peng Liu, Zhaoran Wang
Exploration methods based on pseudo-count of transitions or curiosity of dynamics have achieved promising results in solving reinforcement learning with sparse rewards.
no code implementations • 29 Sep 2021 • Shuxing Li, Jiawei Xu, Chun Yuan, Peng Sun, Zhuobin Zheng, Zhengyou Zhang, Lei Han
We provide comprehensive analysis and experiments to elaborate the effect of each component in affecting the agent performance, and demonstrate that the proposed and adopted techniques are important to achieve superior performance in general end-to-end FPS games.
no code implementations • 29 Sep 2021 • Hao Sun, Lei Han, Jian Guo, Bolei Zhou
We verify our insight on a range of tasks: (1) In offline RL, the conservative exploitation leads to improved learning performance based on off-the-shelf algorithms; (2) In online continuous control, multiple value functions with different shifting constants can be used to trade-off between exploration and exploitation thus improving learning efficiency; (3) In online RL with discrete action space, a negative reward shifting brings an improvement over the previous curiosity-based exploration method.
no code implementations • 29 Sep 2021 • Jiawei Xu, Shuxing Li, Chun Yuan, Zhengyou Zhang, Lei Han
In this paper, inspired by Bootstrapped DQN, we use multiple heads in DDPG and take advantage of the diversity and uncertainty among multiple heads to improve the data efficiency with relabeled goals.
no code implementations • 29 Sep 2021 • Lei Han, Cheng Zhou, Yizheng Zhang
We propose a new general theory measuring the relativity between two arbitrary Markov Decision Processes (MDPs) from the perspective of reinforcement learning (RL).
no code implementations • 30 Aug 2021 • Shenao Zhang, Lei Han, Li Shen
In multi-agent reinforcement learning, the behaviors that agents learn in a single Markov Game (MG) are typically confined to the given agent number (i. e., population size).
Multi-agent Reinforcement Learning
reinforcement-learning
+1
no code implementations • 1 Jul 2021 • Rui Yang, Meng Fang, Lei Han, Yali Du, Feng Luo, Xiu Li
Replacing original goals with virtual goals generated from interaction with a trained dynamics model leads to a novel relabeling method, model-based relabeling (MBR).
1 code implementation • 13 May 2021 • Chenjia Bai, Lingxiao Wang, Lei Han, Jianye Hao, Animesh Garg, Peng Liu, Zhaoran Wang
In this paper, we propose a principled exploration method for DRL through Optimistic Bootstrapping and Backward Induction (OB2I).
no code implementations • 21 Jan 2021 • Yongjian Zhou, Liyang Liao, Xiaofeng Zhou, Hua Bai, Mingkun Zhao, Caihua Wan, Siqi Yin, Lin Huang, Tingwen Guo, Lei Han, Ruyi Chen, Zhiyuan Zhou, Xiufeng Han, Feng Pan, Cheng Song
The interlayer coupling mediated by fermions in ferromagnets brings about parallel and anti-parallel magnetization orientations of two magnetic layers, resulting in the giant magnetoresistance, which forms the foundation in spintronics and accelerates the development of information technology.
Materials Science
1 code implementation • 27 Nov 2020 • Lei Han, Jiechao Xiong, Peng Sun, Xinghai Sun, Meng Fang, Qingwei Guo, Qiaobo Chen, Tengfei Shi, Hongsheng Yu, Xipeng Wu, Zhengyou Zhang
We show that with orders of less computation scale, a faithful reimplementation of AlphaStar's methods can not succeed and the proposed techniques are necessary to ensure TStarBot-X's competitive performance.
1 code implementation • 25 Nov 2020 • Peng Sun, Jiechao Xiong, Lei Han, Xinghai Sun, Shuxing Li, Jiawei Xu, Meng Fang, Zhengyou Zhang
This poses non-trivial difficulties for researchers or engineers and prevents the application of MARL to a broader range of real-world problems.
no code implementations • 17 Oct 2020 • Chenjia Bai, Peng Liu, Kaiyu Liu, Lingxiao Wang, Yingnan Zhao, Lei Han, Zhaoran Wang
Efficient exploration remains a challenging problem in reinforcement learning, especially for tasks where extrinsic rewards from environments are sparse or even totally disregarded.
no code implementations • 18 Jul 2020 • Zhiyong Yu, Lei Han, Chao Chen, Wenzhong Guo, Zhiwen Yu
This paper proposes a strategy named IHMs (Intermediate Searching at Heuristic Moments): each step we figure out which moment is the best to search according to a heuristic indicator, then at that moment search locations one by one in descending order of predicted appearing probabilities, until a search hits; iterate this step until we get the object's current location.
no code implementations • 13 May 2020 • Forrest Sheng Bao, Youbiao He, Jie Liu, Yuanfang Chen, Qian Li, Christina R. Zhang, Lei Han, Baoli Zhu, Yaorong Ge, Shi Chen, Ming Xu, Liu Ouyang
The COVID-19 is sweeping the world with deadly consequences.
no code implementations • CVPR 2020 • Lei Han, Tian Zheng, Lan Xu, Lu Fang
3D instance segmentation, with a variety of applications in robotics and augmented reality, is in large demands these days.
Ranked #1 on
3D Instance Segmentation
on SceneNN
1 code implementation • NeurIPS 2019 • Meng Fang, Tianyi Zhou, Yali Du, Lei Han, Zhengyou Zhang
This ``Goal-and-Curiosity-driven Curriculum Learning'' leads to ``Curriculum-guided HER (CHER)'', which adaptively and dynamically controls the exploration-exploitation trade-off during the learning process via hindsight experience selection.
1 code implementation • NeurIPS 2019 • Yali Du, Lei Han, Meng Fang, Ji Liu, Tianhong Dai, DaCheng Tao
A great challenge in cooperative decentralized multi-agent reinforcement learning (MARL) is generating diversified behaviors for each individual agent when receiving only a team reward.
Multi-agent Reinforcement Learning
reinforcement-learning
+3
no code implementations • 14 Nov 2019 • Lei Han, Juanzhen Sun, Wei zhang
On the first layer of CNN, a cross-channel 3D convolution was proposed to fuse 3D raw data.
no code implementations • 1 Oct 2019 • Wei Zhang, Wei Li, Lei Han
Very short-term convective storm forecasting, termed nowcasting, has long been an important issue and has attracted substantial interest.
no code implementations • 19 Sep 2019 • Yiheng Huang, Jinchuan Tian, Lei Han, Guangsen Wang, Xingcheng Song, Dan Su, Dong Yu
One important challenge of training an NNLM is to leverage between scaling the learning process and handling big data.
no code implementations • 2 Sep 2019 • Yiheng Huang, Liqiang He, Lei Han, Guangsen Wang, Dan Su
In this work, we propose to train pruned language models for the word classes to replace the slots in the root n-gram.
2 code implementations • 20 Jul 2019 • Qing Wang, Jiechao Xiong, Lei Han, Meng Fang, Xinghai Sun, Zhuobin Zheng, Peng Sun, Zhengyou Zhang
We introduce Arena, a toolkit for multi-agent reinforcement learning (MARL) research.
2 code implementations • 3 Apr 2019 • Xiangtai Li, Houlong Zhao, Lei Han, Yunhai Tong, Kuiyuan Yang
Semantic segmentation generates comprehensive understanding of scenes through densely predicting the category for each pixel.
Ranked #25 on
Semantic Segmentation
on Cityscapes test
1 code implementation • 26 Dec 2018 • Lei Han, Mengqi Ji, Lu Fang, Matthias Nießner
Direct image-to-image alignment that relies on the optimization of photometric error metrics suffers from limited convergence range and sensitivity to lighting conditions.
1 code implementation • NeurIPS 2018 • Qing Wang, Jiechao Xiong, Lei Han, Peng Sun, Han Liu, Tong Zhang
We consider deep policy learning with only batched historical trajectories.
4 code implementations • 10 Oct 2018 • Jiechao Xiong, Qing Wang, Zhuoran Yang, Peng Sun, Lei Han, Yang Zheng, Haobo Fu, Tong Zhang, Ji Liu, Han Liu
Most existing deep reinforcement learning (DRL) frameworks consider either discrete action space or continuous action space solely.
3 code implementations • 19 Sep 2018 • Peng Sun, Xinghai Sun, Lei Han, Jiechao Xiong, Qing Wang, Bo Li, Yang Zheng, Ji Liu, Yongsheng Liu, Han Liu, Tong Zhang
Both TStarBot1 and TStarBot2 are able to defeat the built-in AI agents from level 1 to level 10 in a full game (1v1 Zerg-vs-Zerg game on the AbyssalReef map), noting that level 8, level 9, and level 10 are cheating agents with unfair advantages such as full vision on the whole map and resource harvest boosting.
1 code implementation • ICLR 2018 • Jiechao Xiong, Qing Wang, Zhuoran Yang, Peng Sun, Yang Zheng, Lei Han, Haobo Fu, Xiangru Lian, Carson Eisenach, Haichuan Yang, Emmanuel Ekwedike, Bei Peng, Haoyue Gao, Tong Zhang, Ji Liu, Han Liu
Most existing deep reinforcement learning (DRL) frameworks consider action spaces that are either discrete or continuous space.
no code implementations • ICML 2018 • Lei Han, Yiheng Huang, Tong Zhang
This paper proposes a method for multi-class classification problems, where the number of classes K is large.
no code implementations • 18 Sep 2017 • Lei Han, Guyue Zhou, Lan Xu, Lu Fang
The proposed system originates from our previous work Multi-Index hashing for Loop closure Detection (MILD), which employs Multi-Index Hashing (MIH)~\cite{greene1994multi} for Approximate Nearest Neighbor (ANN) search of binary features.
no code implementations • 28 Feb 2017 • Lei Han, Lu Fang
Loop Closure Detection (LCD) has been proved to be extremely useful in global consistent visual Simultaneously Localization and Mapping (SLAM) and appearance-based robot relocalization.
no code implementations • 15 Feb 2017 • Wei Zhang, Lei Han, Juanzhen Sun, Hanyang Guo, Jie Dai
This paper describes the first attempt to nowcast storm initiation, growth, and advection simultaneously under a deep learning framework using multi-source meteorological data.
no code implementations • 7 Nov 2016 • Ye Liu, Liqiang Nie, Lei Han, Luming Zhang, David S. Rosenblum
As compared to simple actions, activities are much more complex, but semantically consistent with a human's real life.
no code implementations • 14 Sep 2016 • Lei Han, Juanzhen Sun, Wei zhang, Yuanyuan Xiu, Hailei Feng, Yinjing Lin
Despite marked progress over the past several decades, convective storm nowcasting remains a challenge because most nowcasting systems are based on linear extrapolation of radar reflectivity without much consideration for other meteorological fields.
no code implementations • 27 Apr 2016 • Lei Han, Kean Ming Tan, Ting Yang, Tong Zhang
A major challenge for building statistical models in the big data era is that the available data volume far exceeds the computational capability.