activity
20122026
most citedOn Neural Network Identification for Low-Speed Ship Maneuvering Model

71 citations · 368 across the 49 of their papers we have counts for

collaborators

53 papers

math.OC2026

Beyond IGO-Flow: Toward Convergence Analysis of IGO in Continuous Spaces

Ryosuke Kimura, Youhei Akimoto

Information-Geometric Optimization (IGO) provides a unified framework for black-box optimization by interpreting the adaptation of a search distribution as a natural gradient updat…

cs.NE2026

Mixed-Categorical Black-Box Optimization via Information-Geometric Bilevel Decomposition

Marc Ong, Shinichi Shirakawa, Youhei Akimoto

Mixed categorical-continuous optimization arises in many practical domains, yet remains challenging. In the black-box setting, evolution strategy-based approaches have shown promis…

cs.NE2026★ 1 cited

Accelerating Black-Box Bilevel Optimization with Rank-Based Upper-Level Value Function Approximation

Marc Ong, Youhei Akimoto

Bilevel optimization is a field of significant theoretical and practical interest, yet solving such optimization problems remains challenging. Evolutionary methods have been employ…

cs.LG2025

Feature selection based on cluster assumption in PU learning

Motonobu Uchikoshi, Youhei Akimoto

Feature selection is essential for efficient data mining and sometimes encounters the positive-unlabeled (PU) learning scenario, where only a few positive labels are available, whi…

cs.NE2025★ 2 cited

Challenges of Interaction in Optimizing Mixed Categorical-Continuous Variables

Youhei Akimoto, Xilin Gao, Ze Kai Ng +1

Optimization of mixed categorical-continuous variables is prevalent in real-world applications of black-box optimization. Recently, CatCMA has been proposed as a method for optimiz…

eess.SY2024

Probabilistic Prediction of Ship Maneuvering Motion using Ensemble Learning with Feedforward Neural Networks

Kouki Wakita, Youhei Akimoto, Atsuo Maki

In the field of Maritime Autonomous Surface Ships (MASS), the accurate modeling of ship maneuvering motion for harbor maneuvers is a crucial technology. Non-parametric system ident…

cs.RO2024

Conceptual Design on the Field of View of Celestial Navigation Systems for Maritime Autonomous Surface Ships

Kouki Wakita, Fuyuki Hane, Takeshi Sekiguchi +4

In order to understand the appropriate field of view (FOV) size of celestial automatic navigation systems for surface ships, we investigate the variations of measurement accuracy o…

cs.NE2024

Tail Bounds on the Runtime of Categorical Compact Genetic Algorithm

Ryoki Hamano, Kento Uchida, Shinichi Shirakawa +2

The majority of theoretical analyses of evolutionary algorithms in the discrete domain focus on binary optimization algorithms, even though black-box optimization on the categorica…

math.OC2024

Simultaneous optimization of control gains and reference filter coefficients for trajectory tracking control

Amane Sakanashi, Rin Suyama, Atsuo Maki +1

Research on vessel automation and autonomy is currently being conducted by various countries and institutions. Safe and accurate ship control algorithms are crucial to realize auto…

cs.NE2024

Theoretical Analysis of Explicit Averaging and Novel Sign Averaging in Comparison-Based Search

Daiki Morinaga, Youhei Akimoto

In black-box optimization, noise in the objective function is inevitable. Noise disrupts the ranking of candidate solutions in comparison-based optimization, possibly deteriorating…

cs.NE2024★ 19 cited

CMA-ES with Learning Rate Adaptation

Masahiro Nomura, Youhei Akimoto, Isao Ono

The covariance matrix adaptation evolution strategy (CMA-ES) is one of the most successful methods for solving continuous black-box optimization problems. A practically useful aspe…

cs.LG2023★ 5 cited

Statistically Significant Concept-based Explanation of Image Classifiers via Model Knockoffs

Kaiwen Xu, Kazuto Fukuchi, Youhei Akimoto +1

A concept-based classifier can explain the decision process of a deep learning model by human-understandable concepts in image classification problems. However, sometimes concept-b…

eess.SY2023★ 9 cited

Data Augmentation Methods of Dynamic Model Identification for Harbor Maneuvers using Feedforward Neural Network

Kouki Wakita, Yoshiki Miyauchi, Youhei Akimoto +1

A dynamic model for an automatic berthing and unberthing controller has to estimate harbor maneuvers, which include berthing, unberthing, approach maneuvers to berths, and entering…

cs.NE2023★ 14 cited

CMA-ES with Learning Rate Adaptation: Can CMA-ES with Default Population Size Solve Multimodal and Noisy Problems?

Masahiro Nomura, Youhei Akimoto, Isao Ono

The covariance matrix adaptation evolution strategy (CMA-ES) is one of the most successful methods for solving black-box continuous optimization problems. One practically useful as…

cs.NE2023

Covariance Matrix Adaptation Evolutionary Strategy with Worst-Case Ranking Approximation for Min--Max Optimization and its Application to Berthing Control Tasks

Atsuhiro Miyagi, Yoshiki Miyauchi, Atsuo Maki +3

In this study, we consider a continuous min--max optimization problem whose objective function is a black-box. We propose a…

physics.flu-dyn2023

Development of a Mathematical Model for Harbor-Maneuvers to Realize Modeling Automation

Yoshiki Miyauchi, Youhei Akimoto, Naoya Umeda +1

A simulation environment of harbor maneuvers is critical for developing automatic berthing. Dynamic models are widely used to estimate harbor maneuvers. However, human decision-mak…

cs.LG2023

Few-Shot Image-to-Semantics Translation for Policy Transfer in Reinforcement Learning

Rei Sato, Kazuto Fukuchi, Jun Sakuma +1

We investigate policy transfer using image-to-semantics translation to mitigate learning difficulties in vision-based robotics control agents. This problem assumes two environments…

eess.SY2022★ 15 cited

Collision probability reduction method for tracking control in automatic docking / berthing using reinforcement learning

Kouki Wakita, Youhei Akimoto, Dimas M. Rachman +3

Automation of berthing maneuvers in shipping is a pressing issue as the berthing maneuver is one of the most stressful tasks seafarers undertake. Berthing control problems are ofte…

cs.NE2022

Adaptive Scenario Subset Selection for Worst-Case Optimization and its Application to Well Placement Optimization

Atsuhiro Miyagi, Kazuto Fukuchi, Jun Sakuma +1

In this study, we consider simulation-based worst-case optimization problems with continuous design variables and a finite scenario set. To reduce the number of simulations require…

cs.LG2022★ 2 cited

Max-Min Off-Policy Actor-Critic Method Focusing on Worst-Case Robustness to Model Misspecification

Takumi Tanabe, Rei Sato, Kazuto Fukuchi +2

In the field of reinforcement learning, because of the high cost and risk of policy training in the real world, policies are trained in a simulation environment and transferred to…

cs.LG2022★ 1 cited

CAMRI Loss: Improving Recall of a Specific Class without Sacrificing Accuracy

Daiki Nishiyama, Kazuto Fukuchi, Youhei Akimoto +1

In real-world applications of multi-class classification models, misclassification in an important class (e.g., stop sign) can be significantly more harmful than in other classes (…

math.OC2022★ 8 cited

Convergence rate of the (1+1)-evolution strategy on locally strongly convex functions with lipschitz continuous gradient

Daiki Morinaga, Kazuto Fukuchi, Jun Sakuma +1

Evolution strategy (ES) is one of the promising classes of algorithms for black-box continuous optimization. Despite its broad successes in applications, theoretical analysis on th…

cs.NE2022★ 2 cited

Black-Box Min--Max Continuous Optimization Using CMA-ES with Worst-case Ranking Approximation

Atsuhiro Miyagi, Kazuto Fukuchi, Jun Sakuma +1

In this study, we investigate the problem of min-max continuous optimization in a black-box setting . A popular approach updates and simultaneously…

cs.NE2022★ 3 cited

Monotone Improvement of Information-Geometric Optimization Algorithms with a Surrogate Function

Youhei Akimoto

A surrogate function is often employed to reduce the number of objective function evaluations for optimization. However, the effect of using a surrogate model in evolutionary appro…