時間序列與收費站模擬模式應用於電子收費車道使用需求預測與車道配置：以泰山收費站為例

Demand Forecast and Lane Allocation of Electronic Toll Collection Using Time Series and TPS Models: A Case Study of Taishan Toll Station

高速公路收費站區為國道高速公路交通瓶頸所在，透過高速公路電子收費系統（ETC）的使用，可以增加收費站容量、縮短收費時間、提高用路人的安全及便利，並具有節省能源及降低污染等多項優點，預計可以改善高速公路收費站區交通擁擠與環境衝擊等問題。我國國道高速公路電子收費系統正式使用以來，泰山收費站電子收費車道雙向使用率最高，且已達政府合約增設車道標準；但申請增設車道的同時，亦遭遇不小的反對聲浪，鑒於高速公路資源有限，如何根據用路人需求與經濟效益等因素，有效配置收費站區之電子與人工收費車道，實為重要的研究課題之一。本研究運用泰山收費站電子收費車道每日通行量歷史資料，以時間序列法建立需求預測模式，並與實際通行量作比較，以驗證模式的可靠程度。其次，本研究運用收費站模擬模式（TPS），分析ETC車道配置數量及使用率對收費站整體服務績效之影響。實證分析結果顯示，僅以ETC車道使用率作為增設ETC車道的標準，恐無法達成改善收費站區整體績效之終極目標。相關研究成果，預計可以提供相關主管機關未來在增設電子收費車道與相關政策之參考。

Traffic congestion and bottleneck are usually observed at toll plaza areas in a freeway system. Implementation of an electronic toll collection (ETC) system is not only able to increase toll plaza throughputs and reduce toll collection time, but it also helps to increase freeway users' safety level and convenience as well as resolve energy consumption and air pollution problems. It is expected to improve the problems associated with traffic congestion and environmental impact at toll plaza areas. Since the formal implementation of ETC in the freeway system of Taiwan, the Taishan toll station has been encountering the most ETC lane usage in both directions. The ETC traffic demands have also reached the threshold of increasing one more ETC lane in each direction. However, some concerns are raised by the general public since extra delays might occur in the manual toll collection lanes. Therefore, in view of the limited freeway resources, there is a crucial research topic on the reasonable allocation of ETC and manual lanes at a toll station under the considerations of freeway users' demand and economic benefits. To tackle this problem, this research first constructs a time series model using the historical traffic flow data to estimate the ETC traffic flow patterns and compares the predicted ETC traffic flows to the observed data to verify the reliability of the constructed time series model. In addition, this research adopts a toll plaza simulation (TPS) model to evaluate the effects of ETC lane allocation and usage on the overall service performance at the Taishan toll station. The empirical study results indicate that the ultimate goals of implementing the ETC system might not be achieved by simply considering the ETC lane usage rate as the only one criterion to open new ETC lanes. The outcomes of this research can be a beneficial reference for the freeway management agency to determine the appropriate timing for adding additional ETC lanes and other relevant polices.