Jun Bi

Prof. Jun Bi

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 February 2019 in Energy
Verified
Journal Article
Closed access
JBJun Bi
Jun Bi
YWYongxing Wang
Yongxing Wang
QSQiuyue Sai
Qiuyue Sai
CDCong Ding
Cong Ding

9 January 2019 in Journal of Advanced Transportation
Verified
Journal Article
Open access
PDF file
SSShuai Sun
Shuai Sun
JZJun Zhang
Jun Zhang
JBJun Bi
Jun Bi
YWYongxing Wang
Yongxing Wang
It is of great significance to improve the driving range prediction accuracy to provide battery electric vehicle users with reliable information. A model built by the conventional multiple linear regression method is feasible to predict the driving range, but the residual errors between -3.6975 km and 3.3865 km are relatively unfaithful for real-world driving. The study is innovative in its application of machine learning method, the gradient boosting decision tree algorithm, on the driving range prediction which includes a very large number of factors that cannot be considered by conventional regression methods. The result of the machine learning method shows that the maximum prediction error is 1.58 km, the minimum prediction error is -1.41 km, and the average prediction error is about 0.7 km. The predictive accuracy of the gradient boosting decision tree is compared against that of the conventional approaches.

5 January 2017 in Mathematical Problems in Engineering
Verified
Journal Article
Open access
PDF file
SSSai Shao
Sai Shao
WGWei Guan
Wei Guan
BRBin Ran
Bin Ran
ZHZhengbing He
Zhengbing He
JBJun Bi
Jun Bi
An electric vehicle routing problem with charging time and variable travel time is developed to address some operational issues such as range limitation and charging demand. The model is solved by using genetic algorithm to obtain the routes, the vehicle departure time at the depot, and the charging plan. Meanwhile, a dynamic Dijkstra algorithm is applied to find the shortest path between any two adjacent nodes along the routes. To prevent the depletion of all battery power and ensure safe operation in transit, electric vehicles with insufficient battery power can be repeatedly recharged at charging stations. The fluctuations in travel time are implemented to reflect a dynamic traffic environment. In conclusion, a large and realistic case study with a road network in the Beijing urban area is conducted to evaluate the model performance and the solution technology and analyze the results.

30 November 2020 in Sustainability
Verified
Journal Article
Open access
PDF file
SWShefang Wang
Shefang Wang
Chaoru LuChaoru Lu
Chaoru Lu
Chenhui LiuChenhui Liu
Chenhui Liu
YZYue Zhou
Yue Zhou
JBJun Bi
Jun Bi
XZXiaomei Zhao
Xiaomei Zhao
The ever-increasing concerns over urban air quality, noise pollution, and considerable savings in total cost of ownership encouraged more and more cities to introduce battery electric buses (e-bus). Based on the sensor records of 99 e-buses that included over 250,000 h across 4.7 million kilometers, this paper unveiled the relationship between driving behaviors and e-bus battery energy consumption under various environments. Battery efficiency was evaluated by the distance traveled per unit battery energy (1% SoC, State of Charge). Mix effect regression was applied to quantify the magnitude and correlation between multiple factors; and 13 machine learning methods were adopted for enhanced prediction and optimization. Although regenerative braking could make a positive contribution to e-bus battery energy recovery, unstable driving styles with greater speed variation or acceleration would consume more energy, hence reduce the battery efficiency. The timing window is another significant factor and the result showed higher efficiency at night, over weekends, or during cooler seasons. Assuming a normal driving behavior, this paper investigated the most economical driving speed in order to maximize battery efficiency. An average of 19% improvement could be achieved, and the optimal driving speed is time-dependent, ranging from 11 to 18 km/h.

1 November 2018 in Measurement
Verified
Journal Article
Closed access
JBJun Bi
Jun Bi
YWYongxing Wang
Yongxing Wang
SSSai Shao
Sai Shao
YCYang Cheng
Yang Cheng

9 May 2020 in Sensors
Verified
Journal Article
Open access
PDF file
SSShuai Sun
Shuai Sun
JBJun Bi
Jun Bi
Montserrat GuillenMontserrat Guillen
Montserrat Guillen
APAna M. Pérez-Marín
Ana M. Pérez-Marín
With the major advances made in internet of vehicles (IoV) technology in recent years, usage-based insurance (UBI) products have emerged to meet market needs. Such products, however, critically depend on driving risk identification and driver classification. Here, ordinary least square and binary logistic regressions are used to calculate a driving risk score on short-term IoV data without accidents and claims. Specifically, the regression results reveal a positive relationship between driving speed, braking times, revolutions per minute and the position of the accelerator pedal. Different classes of risk drivers can thus be identified. This study stresses both the importance and feasibility of using sensor data for driving risk analysis and discusses the implications for traffic safety and motor insurance.