Core Points - The completion of the comprehensive testing train DJ (Dynamic Inspection) 502 on October 9 marks the final phase of the joint debugging and testing work for the Xi'an-Yan'an high-speed railway, laying the foundation for subsequent trial operations and official opening [1] - The comprehensive testing is a crucial dynamic verification step in railway construction, integrating previous individual tests to validate multiple systems including tracks, power supply, and contact networks against design standards [1] - The Xi'an Railway Bureau has adopted a dual-train collaborative model for the testing, utilizing a "comprehensive testing train + confirmation train" approach to conduct systematic tests along the line [1][2] Summary by Sections - **Testing Progress**: The overall progress of the joint debugging and testing has reached 45%, with nearly 100 test trains operated since the initiation, collecting thousands of data points on track geometry, contact network voltage, and signal response speed [2] - **Collaboration and Coordination**: The Xi'an Railway Bureau has formed a command center for the joint debugging and testing, collaborating with over 20 entities including the Shaanxi Company of the Xi'an-Chengdu High-Speed Railway and the China Academy of Railway Sciences [2][3] - **Communication System Testing**: During the testing period, the communication system across the line was debugged, achieving a public network coverage rate of 74% under maximum testing speed conditions [3]