Design and Application of Modular Transportation Status Monitoring System Qingyu Li, Guofa Li, Jili Wang, Xiaocui Zhu, Shenggui Zhang, Jialong He and Jinghao Chen E3S Web Conf., 233 (2021) 04035 Published online: 27 January 2021 DOI: 10.1051/e3sconf/202123304035