以動態車輛路線最佳化模型決定高速公路事件應變車隊任務

Abstract

高速公路的壅塞超過半數是由事件所造成，提升事件處裡的效率能夠降低壅塞所帶來的延滯時間。目前國道的管理係依賴事件應變車隊進行事件的清理與排除，最佳化事件應變車隊的調度為一種有效提升應變效率的方法。本研究的目標為應用最佳化方法提升事件應變作業指派的品質，以縮短應變車隊抵達各事件的應變時間。本研究提出動態調度系統的架構，釐清與分類系統所需輸入或取得的參數，並針對高速公路系統建立應變車隊路徑規劃問題的模型。模型除了最小化總體事件應變時間，也納入動態調度中重新指派車隊與事件類型優先順序的考量，以使調度模型能夠有更多彈性、符合實際的需求。本研究以臺灣北區高速公路路網為研究案例，比較分析動態調度模式與現行調度模式間應變時間的差異。從案例分析中可發現動態調度模式不但能在新事件發生後提供即時總應變時間最小化的指派策略，使尖峰時段的總應變時間下降，也能透過改變相關參數的權重來適度調整重新指派車隊的頻率或事件類別優先處理的順序。本研究可以作為高速公路管理單位建構動態調度系統的參考，特別對於多事件密集發生的狀況下，可幫助調度人員做出更有效率的派遣決策。

According to historic data, more than half of freeway congestion is caused by incidents, and enhancing efficiency of incident response can reduce the delay caused by congestion. For most of freeway management systems, they depend on incident response teams to clean up and remove incidents, and optimizing decision of response team dispatch is an effective way to improve the efficiency of incident response. The goal of this study is to apply an optimization method to enhance the quality of the incident assignment strategy to reduce the response time for the response teams to arrive at each incident. We propose the framework of a dynamic dispatch system, clarify the parameters that need to be input or obtained, and develop a model based on the vehicle routing problem for incident response on the freeways. In addition to minimizing the total incident response time, the model also incorporates the considerations of reassignment and prioritizing incidents in dynamic dispatch, making the dispatch model more flexible and consistent with realism of operational needs. In this study, the roadway network of the Northern District of Taiwan Area Freeway is used for the case study to compare the dynamic dispatch model with the current dispatch approach. It is found that the dynamic dispatch model can provide an incident assignment strategy that minimizes the total response time after a new incident occurs so as to enhance the efficiency of freeway incident response, particularly for the peak period where multiple incidents are likely to occur concurrently. Additionally, it also allows the flexible adjustment of the reassignment frequency or incident priority by changing the weight of the related parameters. Our research can provide the insights agency for the construction of a dynamic dispatch system for freeway management units and help dispatchers make more efficient dispatch decisions.