隨著科技的日新月異，全球定位系統、行動通訊和雲端運算的成熟應用推動了許多新的商業模式蓬勃發展，並促使車輛途程問題的研究重心由靜態轉向動態。近年來，機器學習的應用日益普及。其中，強化學習方法因其泛化能力和高效計算速度，非常適合應對動態車輛途程問題，因為該問題需要即時處理資訊的動態變化。
因此，本研究針對具有軟時間窗格和動態行駛時間的車輛途程問題，採用了改進的動態注意力模型和強化學習方法。具體來說，本研究在前人所提出之動態注意力模型上加入了特徵融合和時間推進的機制，同時簡化了解題流程，以有效應對問題中的時間窗格和動態變化特性。此外，利用強化學習方法對該模型進行訓練，使其能夠逐漸提升求解性能。
為了測試本研究方法的有效性，本研究先與原動態注意力模型進行比較以驗證改進之效果，再與其他動態車輛途程問題所提出的元啟發式方法進行比較。實驗結果顯示，本研究所提出之改進能夠在目標值和訓練時間上有良好的效果，且本研究所提出之方法能在極短的時間內生成比其他元啟發式方法更佳的解。

With the rapid advancement of technology, the mature applications of global positioning systems, mobile communications, and cloud computing have driven the flourishing development of many new business models. This has also shifted the focus of research on vehicle routing problems from static to dynamic. In recent years, the adoption of machine learning has become increasingly widespread. Among these methods, reinforcement learning stands out for its ability to generalize and compute efficiently, making it highly suitable for addressing dynamic vehicle routing problems, which require real-time adaptation to changing information.
Therefore, this study addresses vehicle routing problems with soft time windows and dynamic travel times by adopting an improved dynamic attention model and reinforcement learning methods. Specifically, this study incorporates feature fusion and time advancement mechanisms into the previously proposed dynamic attention model and simplifies the solution process to effectively address the characteristics of time windows and dynamic changes in the problem. Additionally, reinforcement learning methods are used to train the model, enabling it to gradually improve its solution performance.
To evaluate the effectiveness of the proposed method, this study first compared it with the original dynamic attention model to verify the improvements. Subsequently, it was compared with other meta-heuristic methods proposed for the dynamic vehicle routing problem. The experimental results indicate that the improvements proposed in this study achieve favorable outcomes in terms of both objective values and training time. Furthermore, the proposed method can generate better solutions in a significantly shorter time compared to other meta-heuristic methods.

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