Zhiwei Chen

• Doctor of Philosophy
• Assistant Professor at Drexel University

The precise estimation of macroscopic traffic parameters, such as travel time and fuel consumption, is essential for the optimization of traffic management systems. Despite its importance, the comprehensive acquisition of vehicle trajectory data for the calculation of these macroscopic measures presents a challenge. To bridge this gap, this study a...

Motivated by the promising benefits of connected and autonomous vehicles (CAVs) in improving fuel efficiency, mitigating congestion, and enhancing safety, numerous theoretical models have been proposed to plan CAV multiple-step trajectories (time-specific speed/location trajectories) to accomplish various operations. However, limited efforts have b...

The precise estimation of macroscopic traffic parameters, such as travel time and fuel consumption, is essential for the optimization of traffic management systems. Despite its importance, the comprehensive acquisition of vehicle trajectory data for the calculation of these macroscopic measures presents a challenge. To bridge this gap, this study a...

Automated vehicle (AV) shuttles are emerging mobility technologies that have been widely piloted and deployed. Public attitude is critical to the deployment progress and the overall social benefits of automated vehicle (AV) technologies. The AV shuttle demonstration was regarded as a good way for possible attitude improvements. However, not all exi...

Connected and automated vehicle (CAV) platoons have drawn much attention in the past decades, given their potential to reduce fuel consumption, elevate roadway capacity, and enhance traffic safety. As two basic platoon operations, platoon merging and splitting have been widely investigated. This study provides an overview of theoretical models and...

This paper presents an optimal vehicle speed trajectory generation methodology on an isolated signalized intersection under mixed traffic environment. The proposed model contains platoon management, arrival time prediction, speed trajectory generation and vehicle control. The proposed model considers fuel consumption and driving comfort. Field expe...

Big data can help government agencies better make equity-related decisions in transportation systems. However, the lack of disaggregated big data is an obstacle to inform policy actions. In this paper, we review data sources that can be used to investigate transportation equity. Following the general three-step framework for transportation equity o...

Motivated by the promising benefits of connected and autonomous vehicles (CAVs) in improving fuel efficiency, mitigating congestion, and enhancing safety, numerous theoretical models have been proposed to plan CAV multiple-step trajectories (time-specific speed and location trajectories) to accomplish various operations. However, limited efforts ha...

Connected and automated vehicle (CAV) platoons have drawn much attention in the past decades given their potentials in reducing fuel consumption, elevating roadway capacity, and enhancing traffic safety. As two basic platoon operations, platoon merging and splitting have been widely investigated. This study provides an overview of theoretical model...

The “asymmetry” between spatiotemporally varying passenger demand and fixed-capacity transportation supply has been a long-standing problem in urban mass transportation (UMT) systems around the world. The emerging modular autonomous vehicle (MAV) technology offers us an opportunity to close the substantial gap between passenger demand and vehicle c...

The emergence of connected and autonomous vehicles (CAV) is of great significance to the development of transportation systems. This paper proposes a multiple-factors aware car-following (MACF) model for CAVs with the consideration of multiple factors including vehicle co-optimization velocity, velocity difference of multiple PVs, and space headway...

Customized bus (CB) is an increasingly popular mode of transportation in many cities around the world. However, studies on CB network design have mostly overlooked three options that may further improve system performance: passenger-route assignment, passenger transfer, and modular vehicles. To bridge this gap, this paper proposes to design a trans...

Jointly designing vehicle dispatch headway and capacity is a relatively new solution to the demand–supply asymmetry in urban mass transportation studies. This paper studies a new problem of this kind where a transportation corridor operates with modular autonomous vehicles (MAV) enabling station-wise docking; i.e., vehicles can change their formati...

Modular vehicle (MV) technology offers the possibility of flexibly adjusting the vehicle capacity by docking/undocking modular pods into vehicles of different sizes en route to satisfy passenger demand. Based on the MV technology, a modular transit network system (MTNS) concept is proposed to overcome the mismatch between fixed vehicle capacity and...

Assessing the equity impacts of transportation systems/policies has become a crucial component in transportation planning. Existing statistical modeling approaches for transportation equity analysis have typically assumed that parameter estimates are constant across all observations and used data aggregated to certain geographic units for the analy...

The emerging connected and autonomous vehicle (CAV) technologies offer a promising solution to design better lane-changing maneuvers that can reduce the negative impacts of vehicle lane-changing behavior on traffic operations. Existing studies on this topic have predominantly focused on designing lane-changing maneuvers for a subject vehicle (SV) a...

Rapid and on-time baggage transportation plays a crucial role in ensuring customer satisfaction and is an important source of greenhouse gas (GHG) emissions in the aviation sector. Modular vehicle (MV) is an emerging transportation technology that allows vehicles to adjust their capacity flexibly by assembling or disassembling identical detachable...

Since passenger demand in urban transit systems is asymmetrically distributed across different periods in a day and different geographic locations across the cities, the tradeoff between vehicle operating costs and service quality has been a persistent problem in transit operational design. The emerging modular vehicle technology offers us a new pe...

Assessing the equity impacts of transportation systems/policies has become a crucial component in transportation planning. Existing statistical modeling approaches for transportation equity analysis have typically assumed that parameter estimates are constant across all observations and used data aggregated to certain geographic units for the analy...

Jointly designing vehicle dispatch headway and capacity is a relatively new solution to the demand-supply asymmetry in urban mass transportation studies. This paper studies a new problem of this kind where a transportation corridor operates with modular autonomous vehicles (MAV) enabling station-wise docking; i.e., vehicles can change their formati...

This paper studies the problem of deploying electric bicycle (e-bike) sharing stations and determining their capacities, i.e. the number of shared e-bikes and charging piles, considering travelers’ responses to the charging demands and different deployment schemes. Given a one-way station-based setting, we propose an e-bike sharing network where th...

Emerging transportation technologies (e.g., electric vehicles) and services (e.g., shared mobility) provide efficient, sustainable and cost-effective alternatives to traditional travel modes. However, whether these innovative technologies bring benefits to different population groups in an equal and reasonable manner is still an open question. The...

The "asymmetry" between spatiotemporally varying passenger demand and fixed-capacitated transportation supply has been a long-standing problem in urban mass transportation (UMT) systems around the world. The emerging modular autonomous vehicle (MAV) technology offers us an opportunity to close the substantial gap between passenger demand and vehicl...

The rising adoption of bike-sharing systems brings significant benefits to individuals and society as a whole. However, whether these benefits are distributed throughout society in a fair manner is still an open question. This study presents a methodological framework for assessing the equity performance of bike-sharing systems, with Coast Bike Sha...

Time-varying capacity design holds an opportunity to reduce the energy consumption of urban mass transit systems, e.g., urban rail transits, bus rapid transits, modular autonomous vehicles. In this paper, we investigate the joint design of dispatch headway and vehicle capacity for one to one shuttle systems with oversaturated traffic to achieve the...

Existing peak/off-peak based schedules in urban mass transit systems feature two types of dispatch headways and a fixed vehicle capacity across the operational horizon, which lowers their service quality and causes significant energy waste. A promising cure to this challenge is to jointly design the dispatch headways and vehicle capacities in urban...

Dynamic capacity design holds an opportunity to reduce the energy consumption of urban mass transit systems, e.g., urban rail transits, bus rapid transits, modular autonomous vehicles. In this paper, we investigate the joint design of dispatch headway and vehicle capacity for one to one shuttle systems with oversaturated traffic to achieve the opti...

Dynamic capacity design holds a low-hanging opportunity to reduce the energy consumption of urban mass transit systems, e.g., urban rail transits, bus rapid transits, modular autonomous vehicles. In this paper, we investigate the joint design of dispatch headway and vehicle capacity for one to one shuttle systems with oversaturated traffic to achie...

Existing peak/off-peak based schedules in urban mass transit systems feature two types of dispatch headways and a fixed vehicle capacity across the operational horizon, which lowers their service quality and causes significant energy waste. A promising cure to this challenge is to jointly design the dispatch headways and vehicle capacities in urban...

This paper presents a method to assess the safety of uncontrolled intersections considering two major properties of traffic conflicts-conflict probability and severity. This method assesses both the safety level of the entire intersection in addition to the distribution of safety within it. Intersections are modeled by a two-dimensional Cartesian c...