分析都市道路網絡的連結關係於評估交通衝擊地區

Abstract

隨著全球日增的都市發展，交通壅塞已成為一個普遍的問題。解決壅塞中常探討壅塞於何處發生以及生成原因，過去已發展諸多方法在靜態、動態環境中捕捉壅塞發生的地方，然而壅塞發生時所影響的區域卻無所探討，因此無法得知無預期的道路發生壅塞時，受到影響的範圍，並做出交通決策防止進一步的壅塞。過去用於評估影響區域的方法以固定距離法劃定評估範圍，並評估此區域受到的影響，然而此方法適用於評估特定開發案之影響。本研究將評估範圍的定義延伸解釋為有交互作用的地區則會受到影響，並以此概念延伸，藉由建構節點間的連結強度定義子群，子群的特性為內部交互作用大於外部的區域，而這樣的結構特色適於捕捉發生壅塞時的主要影響範圍。 根據研究目的，本研究使用網絡遞移性的理論，建立道路連結關並以連結關係的強弱來定義子群。考量交通流動時的不均流動特性以及資料的限制，以PageRank演算法為基礎發展FBPR(Flow-based PageRank)，並於模式中透過基因演算法協助建立吸引力權重，建立道路間的傳遞關係，並以此關係建立子群。結果顯示，FBPR 藉由遞移能外推的特性建立道路間的流動關係，並以實際流量做為校正，確保FBPR建立之相對流量分布與實際流量分布類似，確立道路之連結關係後。結果顯示道路的流動存在偏向性，並影響路網的流量分布及流量形態。而交通路網的子群結構強烈受到空間及網絡限制，因而有明顯的空間分布特性，在流量較高的地區子群內包含道路較多，顯示了流量高地區的影響範圍較大。 本研究之應用可延伸為兩部分，第一部分為建立道路間的連結，使得未來能以少部分資料推估城市尺度之流量，並將建立之連結關係運用於交通網絡連結分析中。第二部分為確立衝擊區域的範圍，能做為都市規劃者或導航系統做交通決策的參考。

With the growing number of developing cities, traffic congestion has becomes a global issue. To resolve congestion, the first step is to identify where it occurs. Many methods to detect congestion have been developed. However, the geographic extent of the congestion has seldom been discussed. Therefore, when congestion occurs, the roads influencing the problem are unknown, and control strategies cannot be implemented to avoid further congestion. Existing guidelines for conducting traffic impact assessments to determine the extent of impact from congestion define assessment areas based on a certain distance. This study considers other factors that influence the impact area, as distance is not the only factor. This study proposes using Flow-Based PageRank (FBPR) to build link relationships between roads, where the strength of a link relationship represents the intensity of interplay. The community structures index identifies where more interplay occurs, and geographic extent illustrates areas of denser connections, which can indicate impact area. To test the robustness of FBPR, different sizes of data were used. The findings revealed that the values of link relationships were primarily distributed between 0.1 and 0.4 and indicated the existence of a tendency that regulates the flow pattern in a road network. The community structures index value was 0.94 and confirmed the existence of subgroups within the road network. The distribution of community structures was constrained by spatial and network structure, and large communities were distributed in high-volume areas. This indicates that high-volume areas would have a greater impact. In conclusion, FBPR can be used to construct link relationships between roads, and this information can be further applied to link analysis of road networks. The communities in a road network represent geographic subgroups within which interplay is higher, which provides management areas for planners.