Safe Exploration and Optimization of Constrained MDPs Using Gaussian Processes. - Akifumi Wachi; Yanan Sui; Yisong Yue; Masahiro Ono (AAAI, 2018)

Safe Exploration in Markov Decision Processes with Time-Variant Safety using Spatio-Temporal Gaussian Process. - Akifumi Wachi; Hiroshi Kajino; Asim Munawar (CoRR, 2018)

Failure-Scenario Maker for Rule-Based Agent using Multi-agent Adversarial Reinforcement Learning and its Application to Autonomous Driving. - Akifumi Wachi (IJCAI, 2019)

Q-learning with Language Model for Edit-based Unsupervised Summarization. - Ryosuke Kohita; Akifumi Wachi; Yang Zhao; Ryuki Tachibana (EMNLP (1), 2020)

Safe Reinforcement Learning in Constrained Markov Decision Processes. - Akifumi Wachi; Yanan Sui (ICML, 2020)

LOA: Logical Optimal Actions for Text-based Interaction Games. - Daiki Kimura; Subhajit Chaudhury; Masaki Ono; Michiaki Tatsubori; Don Joven Agravante; Asim Munawar; Akifumi Wachi; Ryosuke Kohita; Alexander Gray 001 (ACL (demo), 2021)

Language-based General Action Template for Reinforcement Learning Agents. - Ryosuke Kohita; Akifumi Wachi; Daiki Kimura; Subhajit Chaudhury; Michiaki Tatsubori; Asim Munawar (ACL/IJCNLP (Findings), 2021)

Polar Embedding. - Ran Iwamoto; Ryosuke Kohita; Akifumi Wachi (CoNLL, 2021)

Neuro-Symbolic Reinforcement Learning with First-Order Logic. - Daiki Kimura; Masaki Ono; Subhajit Chaudhury; Ryosuke Kohita; Akifumi Wachi; Don Joven Agravante; Michiaki Tatsubori; Asim Munawar; Alexander Gray 001 (EMNLP (1), 2021)

Safe Policy Optimization with Local Generalized Linear Function Approximations. - Akifumi Wachi; Yunyue Wei; Yanan Sui (NeurIPS, 2021)

Reinforcement Learning with External Knowledge by using Logical Neural Networks. - Daiki Kimura; Subhajit Chaudhury; Akifumi Wachi; Ryosuke Kohita; Asim Munawar; Michiaki Tatsubori; Alexander Gray 001 (CoRR, 2021)

Safe Exploration in Reinforcement Learning: A Generalized Formulation and Algorithms. - Akifumi Wachi; Wataru Hashimoto; Xun Shen; Kazumune Hashimoto (NeurIPS, 2023)

Bayesian Meta-Learning on Control Barrier Functions with Data from On-Board Sensors. - Wataru Hashimoto; Kazumune Hashimoto; Akifumi Wachi; Xun Shen; Masako Kishida; Shigemasa Takai (CoRR, 2023)

Verbosity Bias in Preference Labeling by Large Language Models. - Keita Saito; Akifumi Wachi; Koki Wataoka; Youhei Akimoto (CoRR, 2023)

Long-Term Safe Reinforcement Learning with Binary Feedback. - Akifumi Wachi; Wataru Hashimoto; Kazumune Hashimoto (AAAI, 2024)

Safe Reinforcement Learning Using Model Predictive Control with Probabilistic Control Barrier Function. - Xun Shen; Akifumi Wachi; Wataru Hashimoto; Kazumune Hashimoto; Shigemasa Takai (ACC, 2024)

A Survey of Constraint Formulations in Safe Reinforcement Learning. - Akifumi Wachi; Xun Shen; Yanan Sui (IJCAI, 2024)

Flipping-based Policy for Chance-Constrained Markov Decision Processes. - Xun Shen; Shuo Jiang; Akifumi Wachi; Kazumune Hashimoto; Sebastien Gros (NeurIPS, 2024)

Stepwise Alignment for Constrained Language Model Policy Optimization. - Akifumi Wachi; Thien Q. Tran; Rei Sato; Takumi Tanabe; Youhei Akimoto (NeurIPS, 2024)

Stepwise Alignment for Constrained Language Model Policy Optimization. - Akifumi Wachi; Thien Q. Tran; Rei Sato; Takumi Tanabe; Yohei Akimoto (CoRR, 2024)

Data-efficient safe learning and control with on-board sensors: Bayesian meta-learning and barrier function based approach. - Wataru Hashimoto; Kazumune Hashimoto; Akifumi Wachi; Xun Shen; Masako Kishida; Shigemasa Takai (Adv. Robotics, 2024)

Vulnerability Mitigation for Safety-Aligned Language Models via Debiasing. - Thien Q. Tran; Akifumi Wachi; Rei Sato; Takumi Tanabe; Youhei Akimoto (CoRR, 2025)

Target Return Optimizer for Multi-Game Decision Transformer. - Kensuke Tatematsu; Akifumi Wachi (CoRR, 2025)

Learning-Based Event-Triggered MPC With Gaussian Processes Under Terminal Constraints. - Kazumune Hashimoto; Yuga Onoue; Akifumi Wachi; Xun Shen (IEEE Trans. Cybern., 2025)

Offline Guarded Safe Reinforcement Learning for Medical Treatment Optimization Strategies. - Runze Yan; Xun Shen; Akifumi Wachi; Sebastien Gros; Anni Zhao; Xiao Hu (CoRR, 2025)

A Provable Approach for End-to-End Safe Reinforcement Learning. - Akifumi Wachi; Kohei Miyaguchi; Takumi Tanabe; Rei Sato; Youhei Akimoto (CoRR, 2025)