Operational Design Models For Flexible Transit Systems

The flexible transit system is considered to be a new type of public transport service mode,which has played a significant role in the future public transport market.It has plenty of advantages to the operational process,including its flexibility,customization,and efficiency.Based on the real-world application demand,this study combined the trendy of public transportation in China and considered the impact of new technology simultaneously.This paper summarized the issues in public transit system research and markets and sorted them out as a series of research gaps to fill in the flexible transit system operational designing and modeling.In this study,flexible transit system operational models are proposed in the various background which covered how to select bus stops and its service list,how to optimize their routing and scheduling,how to optimize the bus line length,reduce the unnecessarily stop and increase the service frequency in rural areas,and dynamic ticket fees.These issues are closely related to operational designing and modeling in reducing the cost of flexible transit enterprises and raise the quality level of bus service,which are supposed to be the critical points in the spread of the public transport system.Also,this study did some researches on the electric buses and their recharging process to optimize the efficiency of the power supply.The flexible public traffic system model and the operational strategies in this study are fully extracted from real-world issues with the research goals of realizing the optimization models in solving different modes in specific situations.Due to the lack of organized flexible transit system modeling and optimization theories' support,this study can fulfill some blanks in the market and help both the enterprises and passengers to reach a win-win situation.The main work and research results of this study are listed in the following paragraphs:1)This study goes through the related studies to flexible transit system modeling and discusses the flexible transit system definition,classification,modeling strategies,solving techniques,and the flexible auxiliary system,for example,the electric bus recharging optimization and deployment.Then this study is proposed to satisfy the future development trend of the flexible transit system and promote the diversity of public traffic.2)To deal with the traditional public transport system faces the conflicts of cost-effective and quality services,this study deal with this issue by a two-level bus stops division.The bus stops are divided by the popularity of passengers' demand density and their willingness to pay.Two models are put forward to optimize the operational process,including bus stop schedules,routing,and selective service.One model is based on the use of reservation data,and the other is based on real-time data.Flexible transit systems allow passengers to customize their travel needs and enjoy customized point-to-point services by specifying their origin and destination,departure time range,and willingness to pay.This model and its result can be used by bus enterprises to analyze the expected benefits of transformation from a traditional bus system to a flexible transit system.3)Traditional transit systems face the situation of lacking dynamic bus stops classification method as well as their ticket fee strategies.To fill this research gap,this study proposes a model to optimize the dynamic clarify of bus stops and service selection strategies.This model used historical data and real-time data at the same time.The history data,including land use data,connection data,network facilities,traffic volume,etc.,and the real-time data mainly contain the passengers on the bus stop and their OD demands.In the pricing optimization process,the flexible response coverage of bus stops is considered,and this model weighed the detour cost as well as the passenger coverage.4)The traditional public transport system is facing the issue of too much waiting time for passengers and too many necessary bus-stops to service in low-demand urban areas.This paper proposes a real-time operational scheduling model for a flexible transit system and allows the length of the bus line changes with the travel request changes.This model calculates the service list of all the flexible buses running continuously in the system and optimized the total service time in the system.Based on this flexible transit system and its modeling,the operation strategies can effectively reduce the waiting time of passengers,and reduces the number of unnecessary bus stops in the operation of the flexible public transport system.The optimization result of the model is outstanding in the case of low passenger flow and tide phenomenon.5)Due to the fixed capacity of the traditional buses,traditional public transit systems are unable to adapt to the spatial-temporal demand changes.Based on the new concept of modular vehicle technology,this study proposes a flexible modular transit network system with changeable units.This model allows increase and decrease the number of units under the instruction of optimization result and successfully solves the mismatch between the passenger waiting time is too long,or the low utilization rate of vehicles.In this model,the transit departure frequency and passenger transfer strategies are adjusted to achieve the optimal optimization result of the minimum total system cost.6)The power supply system of flexible electric public transport is explicitly optimized in this paper,and two optimization models are proposed in this field.One is the shared swapping battery model which considering the battery charging rate,the other is dynamic wireless charging lanes that optimize the location,length,and the number of charging lanes simultaneously.These two models effectively solved the power supply issues for long-distance travel for flexible transit systems and improved the utilization of battery in flexible electric public transport systems.And two power supply models provide theoretical support for the development of the modeling of flexible electric public transport auxiliary systems,which are considered of great value in future tendency.This study meets the needs of the flexible public transport development tendency in the market,with a background of intelligence,automation,and electrification,which bring great opportunities in public transport and green lift style.This study mainly focused on the flexible transit system modeling as well as its auxiliary system modeling and doing researches on flexible public transportation route choice,vehicle scheduling,bus stop classification,dynamic ticket prices,electricity supply,etc.These research results provide theoretical support for flexible public transport systems and improve the efficiency and quality of bus services,which is of great significance for promoting public transport in the future.