1. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang’an University, Xi’an, People’s Republic of China
2. Central and Southern China Municipal Engineering Design and Research Institute Co., Ltd., Wuhan, People’s Republic of China
3. The Key Laboratory of Road and Traffic Engineering, Ministry of Education, Tongji University, Shanghai, People’s Republic of China
4. Shaanxi Provincial Communication Construction Group, Xi’an, People’s Republic of China