Transit Priority Research Articles

A Partition-Enabled Multi-Path Signal Optimization under Arterial Progression for Transit Priority

A Partition-Enabled Multi-Path Signal Optimization under Arterial Progression for Transit Priority

Research Progress and Prospects of Transit Priority Signal Intersection Control Considering Carbon Emissions in a Connected Vehicle Environment

Transit priority control is not only an important means for improving the operating speed and reliability of public transport systems, but it is also a key measure for promoting green and sustainable urban transportation development. A review of signal intersection transit priority control strategy in a connected vehicle environment is conducive to discovering important research results on transit priority control at home and abroad and will promote further developments in urban public transport. This study analyzed and reviewed signal intersection transit priority control at four levels: traffic control sub-area divisions, transit signal priority (TSP) strategy, speed guidance strategy, and the impacts of intersection signal control on carbon emissions. In summary, the findings were the following: (1) In traffic control sub-area divisions, the existing methods were mainly based on the similarity of traffic characteristics and used clustering or search methods to divide the intersections with high similarity into the same control sub-areas. (2) The existing studies on the TSP control strategy have mainly focused on transit priority control based on fixed phase sequences or phase combinations under the condition of exclusive bus lanes. (3) Studies on speed guidance strategy were mainly based on using constant bus speeds to predict bus arrival times at intersection stop lines, and it was common to guide only based on bus speed. (4) The carbon emissions model for vehicles within the intersection mainly considered two types of vehicles, namely, fuel vehicles and pure electric vehicles. Finally, by analyzing deficiencies in the existing studies, future development directions for transit priority control are proposed.

EXAMINING THE SAFETY IMPACTS OF TRANSIT PRIORITY SIGNAL SYSTEMS USING SIMULATION TECHNIQUES

Transit Priority Signal (TPS) systems are increasingly used to improve traffic efficiency and reduce passenger waiting times. However, such systems may carry potential safety risks. This study aims to investigate the safety effects of TPS at intersections. Our study utilized the SUMO traffic simulation program to create a road network model containing nine signalized intersections. Subsequently, the TPS system was applied to selected bus routes within the road network, and the cases with and without TPS implementation were compared in terms of safety and performance. In safety-oriented comparisons, surrogate safety measures were employed, including number of conflict and Time to Collision (TTC). Signalized intersection performances were measured and compared in terms of the number and duration of stops. The analysis results indicate that TPS enhances safety and transportation performance for buses, but adversely impacts safety and transportation performance for passenger cars. This study underscores the importance of considering safety aspects in the implementation of TPS aimed at improving passenger transportation efficiency. These findings may contribute to the enhancement of public transportation infrastructure and the implementation of appropriate safety measures.

National Security Priorities for a Sustainable Energy Transition

Relevance. Problems of the sustainability of national economic systems continue to remain relevant for a long time. States continue to interact on climate agendas and environmental topics in a tense geopolitical situation. Expanding the implementation of carbon footprint reduction technologies is becoming a prerequisite for partnerships and entry into new international markets for the supply of products and services. National priorities of states today are moving closer together due to the growing climate crisis, which dictates the need to intensify work on the implementation of ESG projects. The purpose of the study was to analyze the current state of the movement to reduce the carbon footprint and the results of the implementation of declared initiatives within the framework of international agreements. Objectives. The article set and consistently solved the following tasks: a review of the current state of climate change in the environment and the impact of declining environmental quality on the health and longevity of the population was carried out, an assessment was made of the sectoral contribution of various sectors of the economy to the formation and accumulation of greenhouse gases in the atmosphere, an assessment of modern compensation carbon impact tools. Methodology. The work used methods of logical analysis, content analysis, statistical analysis of data on emissions and inputs, graphical and horizontal analysis, generalization and systematization of data. Results. An assessment of the current state of this problem made it possible to summarize the conclusions and results of research on this topic and to identify the main national priorities related to the implementation of strategies for switching to renewable energy sources. Conclusions. The article provides an overview of the level of implementation of resource-saving technologies in various sectors of the Russian national economy. Conclusions are drawn about the need to continue the environmental modernization of the national economic system and expand interstate cooperation on climate change issues and a sustainable energy transition to resource-saving technologies.

A Trajectory‐Based Control Strategy with Vehicle Cooperation and Absolute Transit Priority at an Isolated Intersection

The Dedicated Bus Lane (DBL) is often adopted to ensure transit priority. This is because transit priority can effectively mitigate congestion at the signalized intersection. However, the DBL would cause heavy sacrifices from general vehicles when the frequency of buses is low. To address this issue, many studies were proposed to reduce general vehicles’ sacrifice by converting DBLs into Bus‐Priority Lanes (BPLs). Such BPLs can be intermittently open to general vehicles. However, these studies cannot ensure absolute transit priority when general vehicles access BPLs. With the advance of Connected Automated Vehicle (CAV) technology, this paper proposes a Trajectory‐Based Control (TBC) method for connected automated traffic to approach signalized intersections considering absolute transit priority. A TBC controller is designed to control general vehicles’ trajectories to access BPLs without interference with buses. The TBC controller can balance the multiple cost factors and ensure absolute bus priority. The proposed TBC controller is evaluated against the noncontrol baseline and the state‐of‐the‐art TBC. Sensitivity analysis is conducted under four different congestion levels. The results demonstrate that the proposed TBC method outperforms and has benefits in improving throughputs and fuel efficiency and reducing delays.

A microsimulation study of bus priority system with pre-signaling

The provision of transit priority has been shown to improve the performance of public transport, which is more efficient consumer of energy and space than private transport. On the other hand, the implementation of transit priority may also have disadvantages and penalize the general traffic. Thus, the design of the transit priority needs to balance these two opposing effects. This research aims to implement a bus priority system that utilizes a dedicated bus lane terminated upstream of the intersection, along with an additional signal, known as a pre-signal, at this location. A wide literature exists with studies of adaptive control pre-signals that are primarily focused on isolated intersections and concern simple traffic schemes. The current study investigates the performances of pre-signals in more realistic contexts through microsimulation and focuses specifically on two issues: the position of the pre-signal with respect to the main signal and the application domain of pre-signal strategies compared to the standard layouts of bus lanes, either continuous or interrupted.

A cooperative control method combining signal control and speed control for transit with connected vehicle environment

AbstractTransit operation efficiency and service quality can be enhanced through the implementation of signal and speed control. Previous studies prefer to change driving speed in priority to alleviate the adverse effects of signal timing adjustment on social vehicles. The driving safety and fuel consumption of transit are ignored. To this end, a cooperative control method consisting of three models is proposed. The cooperative control strategy model provides optimal schemes for allocating transit priority time. Based on this, the adjustment of phase time and the transit speed trajectory with the lower fuel consumption are calculated by signal control model and speed control model, respectively. Especially, the signal control model is established in the background of green wave coordinated control to further protect the travelling benefits of social vehicles. The simulation is performed in SUMO to demonstrate the effectiveness of the proposed method. The results show that the cooperative control method improves the crossing efficiency and enhances the fuel economy of transit under different arrival speeds and lengths of control area. Compared with the general signal control, the proposed method can minimize traffic interference, which is particularly obvious in a higher degree of saturation.

Prioritized experience replay in path planning via multi-dimensional transition priority fusion.

Deep deterministic policy gradient (DDPG)-based path planning algorithms for intelligent robots struggle to discern the value of experience transitions during training due to their reliance on a random experience replay. This can lead to inappropriate sampling of experience transitions and overemphasis on edge experience transitions. As a result, the algorithm's convergence becomes slower, and the success rate of path planning diminishes. We comprehensively examines the impacts of immediate reward, temporal-difference error (TD-error), and Actor network loss function on the training process. It calculates experience transition priorities based on these three factors. Subsequently, using information entropy as a weight, the three calculated priorities are merged to determine the final priority of the experience transition. In addition, we introduce a method for adaptively adjusting the priority of positive experience transitions to focus on positive experience transitions and maintain a balanced distribution. Finally, the sampling probability of each experience transition is derived from its respective priority. The experimental results showed that the test time of our method is shorter than that of PER algorithm, and the number of collisions with obstacles is less. It indicated that the determined experience transition priority accurately gauges the significance of distinct experience transitions for path planning algorithm training. This method enhances the utilization rate of transition conversion and the convergence speed of the algorithm and also improves the success rate of path planning.

A hybrid weighting method with a new score function for analyzing investment priorities in renewable energy

The transition to renewable energy sources is a critical challenge that emerging economies are facing today. Investment decisions related to the renewable energy transition involve multiple criteria and objectives that need to be analyzed and evaluated before making informed choices. This study develops a score function, the partitioned dual Muirhead mean (PDMM), the q-rung orthopair fuzzy weighted PDMM (q-ROFWPDMM), and a hybrid weighting technique based on Shannon entropy and decision-making trial and evaluation laboratory (DEMATEL) methods for q-rung orthopair fuzzy information. Additionally, a new multi-criteria group decision-making (MCGDM) technique is constructed using these developed approaches. This approach is applied to analyze the investment priorities of the renewable energy transition for emerging economies (E7 countries). It considers twelve criteria in four dimensions: (i) regulations to increase the renewable potential; (ii) supply of renewable materials; (iii) encouragement of private sector investors in the renewable industry; and (iv) awareness of renewable energy consumption. The results of the hybrid weight finding technique indicate that the “reducing market risk” criterion is the most important for investment priorities. The application of the novel MCGDM technique reveals compelling results, indicating that China has emerged as the frontrunner in effectively bolstering renewable energy investment projects. Moreover, a sensitivity analysis is presented, followed by a comparative analysis in which four conventional and three partition based aggregation operators are considered to show the effectiveness of the developed approach. The proposed approach provides a comprehensive analysis of investment priorities for the renewable energy transition, aiding decision-makers in making informed investment choices.

Identifying Themes in Energy Poverty Research: Energy Justice Implications for Policy, Programs, and the Clean Energy Transition

Energy poverty affects numerous households across the globe and has several key implications and concerns for public health and social equity. Energy poverty is defined as “the lack of access to modern and affordable energy services”. Individuals or communities in energy poverty face limitations in accessing reliable, affordable, and sustainable energy. This review paper examines a focused subset of recent research on energy poverty highlighted by the “NSF 2026: Priorities and Research Needs for an Equitable Energy Transition” workshop and the United States Department of Energy’s Office of Energy Justice Policy and Analysis to help frame energy poverty’s impacts on policy, poverty alleviation, environmental impact, and social inequity. This review paper uses five themes to organize previous energy poverty work: (1) Energy Poverty and Justice Definitions and Metrics; (2) Behavioral Aspects of Energy Poverty; (3) Efficacy of Energy Assistance Programs; (4) Efficiency of Energy Efficiency Policy; (5) The Energy Transition and Environmental and Energy Justice. We found that the literature examined how comprehensive assessment of energy poverty requires going beyond standard statistics and metrics and must include an understanding of how underserved households interact with energy. We found strong optimism for the clean energy transition’s ability to significantly alleviate energy poverty, but only if policymakers include equity. Finally, we found that while there is plenty of work highlighting deficiencies there is a dearth of work examining successful implementations and how to replicate them which will be needed if the clean energy transition is to match its potential.

Evaluation of Driver Comprehension and Compliance of Red-Colored Pavement Markings for Transit Lanes in Portland, Oregon

Many U.S. agencies have experimented with red-colored pavement markings in transit lanes to enhance the message that they are restricted to transit vehicles. This study evaluated nontransit drivers’ comprehension of and compliance with red-colored lane markings in transit priority lanes intended to communicate lane restrictions and appropriate turning and merging locations. Two complementary research methods were used: 1) an online survey of drivers’ comprehension of red-colored pavement markings, and 2) evaluation of video collected at locations pre and post installation of red-colored pavement markings. In the survey, most drivers recognized the red pavement color as a restriction on use, but most did not associate it specifically with transit, or understand the intended meaning of the broken red bar patterns designed to designate a merge area. However, we observed relatively high compliance rates with the transit lane restrictions, and the red pavement coloring was generally associated with improved compliance. Of the 22,803 vehicles observed at these locations, 206 were observed driving in the transit lanes, accounting for a violation rate of 0.9%. For the locations with pre and post data, driving-in-transit-lane violations were either reduced or there was no significant change. For locations with shared turn and transit lanes, between 62% and 76% of drivers merged as intended, and we observed an increase in appropriate merging behavior with the addition of red pavement color.

Location of transit-oriented development stations based on multimodal network equilibrium: Bi-level programming and paradoxes

The unique relationship between the value capture mechanism (VCM) and transit-oriented development (TOD) stations and their peripheral areas, which progressively develops an expanded multimodal network, is well acknowledged in the transport industry. However, in regards to the location of TOD stations, insufficient attention has been paid to user travel behaviours and the operating mechanism of the multimodal network. To bridge this research gap, we develop a bi-level programming model for the location of TOD stations that analyses user travel behaviour in the multimodal network. The VCM and transit priority are the objectives of the upper level of this multi-objective optimization model. And the lower level of the model is a modified multimodal network equilibrium based on the Davidson function. Using a simple numerical simulation, this study proposes explanations for some traffic paradoxes from the perspective of a multimodal network equilibrium. We also illustrate competition and collaboration between rail and bus transport systems. Finally, this study uses an empirical case to describe the feasibility and applicability of the model. The results demonstrate that the location of TOD stations is not only one of the keys to the competitiveness of public transport but is also relevant to implementing its VCM.

Perimeter control in a mixed bimodal bathtub model

Perimeter control involves monitoring network-wide traffic and regulating traffic inflow to alleviate hypercongestion. Implementation of transit priority with perimeter control measures, which allow transit into a controlled area without queuing at the perimeter boundary, is an effective strategy in bimodal transportation systems. However, travelers’ behavior changes in response to perimeter control strategies, such as shifts in their departure times and transportation modes, have not been fully investigated. Therefore, important questions remain, such as the use of transit during perimeter control with transit priority. This paper examines the travelers’ behavior changes in response to perimeter control with transit priority in a mixed bimodal transportation system with cars and flexible route transit (FRT) vehicles. We model departure time and transportation mode choices in such a transportation system with hypercongestion and discomfort in FRT (called the mixed bimodal bathtub model). Initially, we investigate the properties of dynamic user equilibrium without perimeter control. Then, we study the equilibrium patterns during perimeter control with transit priority. Unlike existing works, we find that the number of FRT passengers decreases with time toward the desired arrival time and that FRT may not be used around the peak of rush hour. Furthermore, transit priority may not be sufficient to promote the use of FRT, and additional incentive such as subsidy for lower fares may be required to encourage FRT use during perimeter control. Finally, we show that operating many FRT vehicles does not always decrease the equilibrium cost, even under perimeter control with transit priority.

Decomposed Nearest Level PWM Method With Reduced Switching Frequency for MMC

For modular multilevel converters in medium-voltage applications, the nearest level pulse width modulation (NL-PWM), which combines the nearest level modulation (NLM) with pulse width modulation (PWM), has the advantage of better harmonic characteristics over conventional NLM. However, the introduction of high-frequency PWM also results in a significant increase in switching frequency. To solve this issue, a decomposed NL-PWM method is proposed in this article. By properly allocating the rising edge and falling edge of PWM to two different SMs, the capacitor voltage differences can be decreased more efficiently. On this basis, the allocation priority of different switching transitions is quantitatively analyzed, and then a new voltage-balancing strategy involving five switching modes is proposed. Moreover, to achieve a good tradeoff between voltage-balancing effect and switching loss, the relationship between voltage threshold and switching frequency under the proposed method is also derived. Finally, the comparative simulation and experimental results demonstrate the superiority of the proposed method in different aspects of performance.

Automatic Design of Optimal Actuated Traffic Signal Plans With Active Transit Priority

Automatic Design of Optimal Actuated Traffic Signal Plans With Active Transit Priority

Planning and Deploying Transit Signal Priority in Small and Medium-Sized Cities: Burlington, Vermont, Case Study

Innovations in traffic signal systems have generated a great deal of interest in the provision of preferential traffic signal strategies and treatments for transit buses and other vehicles at signalized intersections in cities of all sizes. The primary objective of this paper is three fold: 1) to synthesize the literature of the lessons learned associated with planning and deploying transit signal priority (TSP) strategies in small and medium-sized cities; 2) to demonstrate the application of a micro-simulation model, VISSIM, to assess transit priority impacts in small and medium-sized communities where the required VISSIM input data are often limited; and 3) to present guidelines to aid traffic engineers and transit planners who are considering TSP strategies in small and medium-sized cities. An underlying aim of this paper is to recognize the differences in transit priority planning and deployment in small and medium-sized cities as compared to major metropolitan areas.

Simulated Analysis of Exclusive Bus Lanes on Expressways: Case Study in Beijing, China

Deploying exclusive bus lanes is considered an important strategy for supporting public transit priority policy. This paper uses a simulation approach to evaluate planned exclusive bus lanes on expressways in Beijing, China. Two scenarios for deploying exclusive bus lanes—a curbside bus lane scenario and a median bus lane scenario—were designed. Then, a micro-simulation network platform using VISSIM was established and calibrated, with all relative errors between the simulated timevarying speeds and the field speeds less than 15 percent. Afterwards, the two bus lane scenarios were simulated, evaluated, and subsequently compared with current traffic conditions without bus lanes. It was found that for both the mainline and the whole network, the operational efficiencies of buses, general traffic, and all mixed traffic are improved with the deployment of exclusive bus lanes. Further, the median bus lane scenario slightly outperforms the curbside bus lane scenario in this case.

A DSS Framework for Advanced Traffic Signal Control System Investment Planning

This article presents ongoing research on the initial development of a decision support system (DSS) framework for integrated emergency vehicle preemption and transit priority system investment planning. A conceptual intelligent DSS framework provides a holistic framework to perform analytical assessments of integrated emergency vehicle preemption and transit priority systems. Three analytical tools are presented for incorporation into future DSS design: the first addresses the potential impact of transit travel time reduction on transit operating costs; the second addresses the potential impact of reduced emergency vehicle crashes at signalized intersections on fire and rescue operating costs; and the third integrates fuzzy sets concepts and multiattribute decision-making methods to rank order transit signal priority strategy alternatives at the intersection level.

Risk-Based Formulation of the Transit Priority Network Design

Demand uncertainties are inevitable in transportation networks. The transit priority network design problem over more than a decade of development has been solved under deterministic conditions. This paper proposes a model to find the optimal transit priority scheme in a multimodal transportation network under uncertain demand. This model is formulated as a risk-based bi-level optimization problem. At the upper-level, a risk measure of expected social cost is minimized subject to a chance constraint on total travel time with a user-specified confidence level and a budget constraint. At the lower-level, a mode choice, a traffic user equilibrium assignment, and a transit assignment are applied. An ant colony algorithm is utilized to solve this complex design problem. Numerical results using a real world middle-size city network empirically demonstrate that the demand uncertainty has a significant impact on the solution and the proposed model is applicable to realistic networks.

Addressing the Treatment and Service Needs of Young Adults with Attention Deficit Hyperactivity Disorder.

The transition from adolescence to adulthood is a complex period in which multiple changes take place (education, work, independent living, and social relations). This stage is especially difficult for adolescents suffering from attention deficit hyperactivity disorder (ADHD), who have to move on from child and adolescent mental health services to adult mental health services. This review analyzes developmental and environmental risk and protective factors as well as critical variables such as executive functioning and self-monitoring that influence the course of ADHD in transitional age youth and guide the priorities for an optimal transition of care. The influence of the COVID-19 pandemic is also discussed. We reflect on the unmet needs for an optimal transition of care and propose practice and policy recommendations to achieve this goal.