Xingchen Yan

Features of bicycle abreast riding and its application in bicycle facility operating evaluation and design optimization

This article aims to measure bicycle facility operating state based on the survey and analysis of bicycles’ abreast riding. We conducted a detailed bicycle operating investigation consisting of four exclusive bicycle paths in Nanjing, China, and introduced an approach to extract the data of bicycle abreast riding from bicycle arrival data. Then, the relationships between bicycle volume and bicycle group size, abreast riding number, lateral clearance, and path width occupancy were discussed. In the end, we compared passing event, macro bicycle flow parameter, and single riding ratio in representing a cyclist’s individual comfort, suitability, and difficulty to data acquisition. The results and conclusions we obtained are as follows: (1) bicycle group size, abreast riding, and path width availability keep a positive correlation with bicycle volume, respectively, while single riding proportion and lateral clearance have a negative relationship with it. (2) Bicycle single riding proportion is a better parameter reflecting bicycle level of service from an objective perspective. We first studied bicycle abreast riding from a vantage point of bicycle group. Single riding proportion offers bicycle facility appraisers another possible choice to assess bicycle level of service. Path width occupancy is very useful in optimizing bicycle facility.

Impact of Curbside Parking on Bicycle Lane Capacity in Nanjing, China:

As roadway resources are being occupied by curbside parking and because of the operational characteristics of parking maneuvers, the capacity of the adjacent travel lane can be significantly reduced. To analyze the influence of curbside parking on the capacity of the bicycle lane, a conflict technique based on additive conflict flow was applied to establish the base capacity model. The actual capacity of the bicycle lane with curb parking was then established by adjusting the base capacity to reflect the influence: lane width, the time influence of parking maneuvers, and proportion of e-bikes. Eight datasets from the exclusive bicycle lanes with different widths and parking maneuvers were collected in Nanjing, China for calibration and evaluation purposes. As a result of a higher number of parking maneuvers, the Emeiling Road was taken as the main case study. The capacity of the bicycle lane was calculated, and the effectiveness of the proposed method was validated by the speed-density-volume relationship model. The proposed model was applied to analyze the effect of different positions of parking berths on the capacity. The results indicate that, with around 65% share of e-bikes, the estimated capacity of Emeiling Road is 2622 bicycles/h, decreasing by 47.10% under the influence of curbside parking. The results also imply that the berths near the openings of the isolation belt have less influence than those in the middle position. These findings could be helpful and useful for practitioners to improve the capacity of bicycle lanes under the influence of curbside parking.

KALMAN FILTERING ESTIMATION OF ARRIVAL RATE FOR OFF-STREET PARKING LOTS

Estimating accurately the arrival rate of the off-street parking lot is very important for studying the impact the park imposes to the main road. The data in this paper are derived from raw counts by the video. Then the Kalman filtering estimation is applied for estimating the arrival numbers of different time steps. Using the Matlab, Kalman filtering estimation gets good results. The results obtained demonstrate that the Kalman filtering is fit for the arrival rate prediction. Through comparing the results of different time steps, two conclusions can be got: the more time steps are taken into the model, the result will be better; the results of longer time step are better than the shorter.