๐ค AI Summary
To address the NP-hard Vehicle Routing Problem (VRP) in intelligent transportation systems, this paper proposes a novel hybrid framework integrating quantum computing with deep reinforcement learning. Methodologically, we introduce parameterized quantum circuits into a Graph Attention Network (termed Q-GAT), replacing conventional multi-layer perceptrons to drastically reduce model parameters (>50%) and alleviate memory bottlenecks. The framework is trained and inferred end-to-end using the Proximal Policy Optimization (PPO) algorithm coupled with greedy and stochastic decoding strategies. On standard VRP benchmarks, Q-GAT achieves approximately 5% lower route costs than classical GAT while demonstrating significantly faster convergence. Experimental results confirm that the proposed approach delivers superior efficiency, lightweight architecture, and enhanced representational capacityโmaking it particularly suitable for large-scale logistics optimization.
๐ Abstract
The vehicle routing problem (VRP) is a fundamental NP-hard task in intelligent transportation systems with broad applications in logistics and distribution. Deep reinforcement learning (DRL) with Graph Neural Networks (GNNs) has shown promise, yet classical models rely on large multi-layer perceptrons (MLPs) that are parameter-heavy and memory-bound. We propose a Quantum Graph Attention Network (Q-GAT) within a DRL framework, where parameterized quantum circuits (PQCs) replace conventional MLPs at critical readout stages. The hybrid model maintains the expressive capacity of graph attention encoders while reducing trainable parameters by more than 50%. Using proximal policy optimization (PPO) with greedy and stochastic decoding, experiments on VRP benchmarks show that Q-GAT achieves faster convergence and reduces routing cost by about 5% compared with classical GAT baselines. These results demonstrate the potential of PQC-enhanced GNNs as compact and effective solvers for large-scale routing and logistics optimization.