Traf_PM_Dist

View metadata for key information about this dataset. Preventative maintenance is necessary for traffic signals and is performed while the equipment is still working, so that it does not break down unexpectedly. This layer was developed to aid the Traffic Division in planning, organizing, and maintaining traffic flow within the City of Philadelphia. Examples include: the maintenance and placing of stop signs and signals and monitoring street travel direction. This polygon layer also has an accompanying arc layer. For questions about this dataset, contact [e-mail]. For technical assistance, email [e-mail].查看元数据（metadata）以获取本数据集的关键信息。交通信号设施需开展预防性维护，且需在设备仍正常运行时进行，以防突发故障。本图层专为协助费城市交通部门规划、统筹及维护市内交通流而开发。相关工作示例包括：停车标志与交通信号设施的维护、布设，以及街道通行方向的监测。该面状图层还配套有弧段图层。若对本数据集有疑问，请发送邮件至[e-mail]；如需技术支持，请发送邮件至[e-mail]。