arXiv subjects

Jiaao Ma

Publications and source records attributed to Jiaao Ma.

3 recordsLinked to original sources

arXiv2026

Diffusion-Guided Cooperative Policy Learning for Target Tracking Based on Underwater Mobile Agent Networks

Multi-agent reinforcement learning (MARL) provides a promising solution for cooperative target tracking in networks of autonomous underwater vehicles (AUVs). However, existing methods still face three major challenges: 1) policy non-stationarity caused by concurrent updates among multiple agents; 2) inefficient policy learning caused by the heterogeneous quality of experiences accumulated during exploration; and 3) policy drift between stochastic exploration and deterministic execution under dynamic underwater disturbances. To address these challenges, this paper develops a four-layer hierarchical MARL architecture comprising global training scheduling, multi-agent coordination, local policy generation, and real-time action execution. Building on this architecture, we propose a Supervised Diffusion-Aided MARL (SDA-MARL) algorithm with three closely coupled mechanisms. First, a dual-decision policy integrates a diffusion-based generative branch with a Deep Deterministic Policy Gradient (DDPG) branch, while segregated experience pools reduce training interference between the two branches. Second, a supervised sample-selection mechanism identifies high-quality tracking transitions and uses their actions to guide reverse diffusion, enabling the generative policy to concentrate on effective regions of the action space. Third, a behavioral-cloning loss transfers diffusion-generated actions to the deterministic DDPG Actor, thereby aligning exploration with execution and suppressing policy drift. Experiments conducted in six-degree-of-freedom underwater environments across multiple AUV-target configurations show that SDA-MARL achieves faster convergence, higher tracking accuracy, more consistent inter-AUV velocities, and shorter tracking paths than the compared MARL methods.

cs.NI↗

arXiv2026

Multi-AUV Ad-hoc network-based Target Tracking: A Value Gradient Guidance Multi-Agent Diffusion Reinforcement Learning Approach

Multi-AUV ad-hoc network-based target tracking requires networked autonomous underwater vehicles (AUVs) to cooperatively track maneuvering targets under constrained acoustic communication, dynamic topology, and uncertain ocean disturbances. Although multi-agent reinforcement learning (MARL) enables decentralized coordination through centralized training, existing methods suffer from high-dimensional joint state-action modeling, noise-sensitive policy generation, leading to unstable training and degraded tracking. To address these issues, we propose VGG-MADiffRL, a value-gradient-guided multi-agent diffusion RL algorithm, and MDCA, a diffusion?based hierarchical control architecture. Leveraging underwater mission characteristics, we model sonar detection mechanisms and ocean current disturbances, formulating cooperative tracking for multi-AUV ad-hoc networks as an MDP. The proposed MDCA constitutes a three-tier closed-loop control framework: a global intelligent control layer, a local online training layer, and a physical action execution layer. This structure enables synergistic optimization across task allocation, local decision processes, and execution feedback. Within MDCA, the local online training layer is the policy learning framework; VGG-MADiffRL builds on diffusion policies and incorporates value gradients to guide action generation in the reverse denoising process, steering the generated actions towards higher expected returns. It employs twin value networks with joint optimization and soft target updates to mitigate overestimation and training oscillations, promoting more stable convergence. Experimental results show that VGG-MADiffRL consistently achieves faster convergence, higher tracking accuracy, and smoother training dynamics in cooperative tracking scenarios, validating its effectiveness and practical engineering value in dynamic underwater settings.

cs.LG↗

arXiv2025

A Scalable Architecture for Efficient Multi-bit Fully Homomorphic Encryption

In the era of cloud computing, privacy-preserving computation offloading is crucial for safeguarding sensitive data. Fully Homomorphic Encryption (FHE) enables secure processing of encrypted data, but the inherent computational complexity of FHE operations introduces significant computational overhead on the server side. FHE schemes often face a tradeoff between efficiency and versatility. While the CKKS scheme is highly efficient for polynomial operations, it lacks the flexibility of the binary TFHE (Torus-FHE) scheme, which offers greater versatility but at the cost of efficiency. The recent multi-bit TFHE extension offers greater flexibility and performance by supporting native non-polynomial operations and efficient integer processing. However, current implementations of multi-bit TFHE are constrained by its narrower numeric representation, which prevents its adoption in applications requiring wider numeric representations. To address this challenge, we introduce Taurus, a hardware accelerator designed to enhance the efficiency of multi-bit TFHE computations. Taurus supports ciphertexts up to 10 bits by leveraging novel FFT units and optimizing memory bandwidth through key reuse strategies. We also propose a compiler with operation deduplication to improve memory utilization. Our experiment results demonstrate that Taurus achieves up to 2600x speedup over a CPU, 1200x speedup over a GPU, and up to 7x faster compared to the previous state-of-the-art TFHE accelerator. Moreover, Taurus is the first accelerator to demonstrate privacy-preserving inference with large language models such as GPT-2. These advancements enable more practical and scalable applications of privacy-preserving computation in cloud environments.

cs.AR↗