标题： 城市层级：基于网络的圣地亚哥交通生态系统见解 显示英文标题

标题： Layers of a City: Network-Based Insights into San Diego's Transportation Ecosystem

摘要： 分析城市交通网络的结构和功能对于提高流动性、公平性和韧性至关重要。 本文利用网络科学对圣地亚哥的交通系统进行多模式分析。 我们使用来自开放街道地图（OSM）和圣地亚哥都会交通系统（MTS）的数据构建了一个多层图，表示驾车、步行和公共交通层。 通过整合数千个兴趣点（POIs），我们通过中心性度量、社区检测和一种提出的步行性指标来分析网络可达性、结构和韧性。 我们的分析揭示了一个由明显的核心-边缘分化定义的系统。 我们发现，虽然城市核心地区联系紧密，但30.3%的兴趣点在步行距离内无法到达公共交通，表明郊区和农村地区的访问存在显著的公平性差距。 中心性分析强调了驾驶网络对关键高速公路的过度依赖作为瓶颈，表明网络韧性较低，同时确认圣地亚哥不是一个广泛可步行的城市。 此外，社区检测表明，交通方式决定了移动性的规模，为步行产生紧凑的本地集群，为驾驶产生广泛的区域集群。 总体而言，这项工作提供了一个全面的框架来诊断城市交通系统，提供了定量见解，可以指导有针对性的干预措施，以改善圣地亚哥的交通公平性和基础设施韧性。 显示英文摘要

摘要： Analyzing the structure and function of urban transportation networks is critical for enhancing mobility, equity, and resilience. This paper leverages network science to conduct a multi-modal analysis of San Diego's transportation system. We construct a multi-layer graph using data from OpenStreetMap (OSM) and the San Diego Metropolitan Transit System (MTS), representing driving, walking, and public transit layers. By integrating thousands of Points of Interest (POIs), we analyze network accessibility, structure, and resilience through centrality measures, community detection, and a proposed metric for walkability. Our analysis reveals a system defined by a stark core-periphery divide. We find that while the urban core is well-integrated, 30.3% of POIs are isolated from public transit within a walkable distance, indicating significant equity gaps in suburban and rural access. Centrality analysis highlights the driving network's over-reliance on critical freeways as bottlenecks, suggesting low network resilience, while confirming that San Diego is not a broadly walkable city. Furthermore, community detection demonstrates that transportation mode dictates the scale of mobility, producing compact, local clusters for walking and broad, regional clusters for driving. Collectively, this work provides a comprehensive framework for diagnosing urban mobility systems, offering quantitative insights that can inform targeted interventions to improve transportation equity and infrastructure resilience in San Diego.