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Mobility as a Service (MaaS) is a recent innovative transport concept, anticipated to oblige significant changes in current transport practices. This study aimed to develop a methodology to justify the potential MaaS adoption. For this purpose, an innovative methodology is presented to identify four types of stations, including "Transit (servicing travelers by bus)", "Micro-mobility (servicing travelers by bike and scooter)", "MaaS (servicing travelers by bus, bike, scooter, and Uber)", and "None (no station)" for each node. The proposed methodology minimizes the total user and agency costs, including user travel time cost, out-of-pocket costs, agency construction costs for MaaS and agency MaaS operating costs. The methodology was tested with a 100 node transport network with existing bus routes. The following results were acquired: 1) Construction of micro-mobility station was not justified for 42 nodes and 37 nodes in 20-years and 30-years life cycles if only 20% of demand from shortest path demand select micro-mobility options 2) Over 20-years and 30-years life cycles, the operator benefits from daily savings amounting to $18,520 and $16,033, respectively, and 3) There are no consistent results to justify the MaaS construction and operation based on existence of the transit stations. In other words, the justification depends on users' shortest trip paths, amount of demand, and existing transit stations. [ABSTRACT FROM AUTHOR]

Transit agencies in the US have shown great interests in the possibility of incorporating on-demand shared mobility modes into their fixed-route transit services. However, the cost-effectiveness of on-demand modes has not been clearly demonstrated, and there lacks an effective method for transit agencies to compare the costs of different service provision options. This study develops an economic-theory-based framework that appropriately conceptualizes the total economic cost of incorporating on-demand modes into transit. Based on the theoretical framework, a simulation model is built to operationalize an approach for evaluating the cost-effectiveness of transit-supplementing, on-demand mobility services. We demonstrate the applicability of this approach using Via to Transit program in the Seattle region. By accounting for both the service provider's cost and the users' cost, we obtain a more complete and accurate measure for the cost advantages of the on-demand modes in this case in comparison to expanding fixed-route transit, where the total economic cost for the on-demand mode is 22% lower than the fixed route transit. The theoretical framework and the simulation model can support the decision-making of public transit agencies as they explore incorporating mobility on demand to supplement traditional transit. • This paper conceptualized the economic cost of incorporating on-demand mobility into transit. • It built a simulation model to compare the cost-effectiveness of on-demand mobility with those of traditional options. • It applied this analytical approach to evaluate Via to Transit, an on-demand mobility pilot program in the Seattle region. • It measured more completely and accurately the economic advantages of the on-demand mobility in our case study area. [ABSTRACT FROM AUTHOR]

This study designs a limited-stop and local mixed bus service from the perspectives of both transit agencies and passengers based on a proposed optimization model. Close attention was paid to the increase in fares for the limited-stop service in the proposed model to offset the loss in bus fare. The objective function was to minimize the passenger travel time and bus agency costs; the decision variables were the stops for the limited-stop service and the headways of the limited-stop and local services; the constraints included the range of fare increases for the limited-stop service and other factors. The Lingo software and the genetic algorithm were compared in solving the proposed model from the aspects of solving time and results. Because the solutions for the model within the planning time and the influence of the global optimal solution upon parametric analysis were stable, the Lingo software was more suitable for the proposed model. Evaluations of the total costs for the mixed service and local-only service were carried out for different bus corridor lengths. The ratio of the fares for the limited-stop service to the fares for the local service must be within the appropriate range in order to take advantage of the limited-stop service. When the stop spacing and the bus corridor distance were longer, the mixed service was more competitive and noticeable. [ABSTRACT FROM AUTHOR]

Many governments in the global south are grappling with challenges of improving the quality of informal transport, and an inability to pay for service improvements. This paper asks the question whether efficiency benefits might be gained through strategic implementation of once-off infrastructure interventions providing priority to informal vehicles at intersections. We note that informal drivers already indicate this demand through (illegal) driving behaviour in traffic. We use a drone to observe indicative behaviours among minibus-taxi drivers in South Africa. We identify interventions that would formalise this behaviour: a single lane pre-signal strategy, queue-jumping lane, and dedicated public transport lane. The objective of the paper is to quantify the potential economic impacts of such treatments on minibus-taxi operators, passengers and other road users. The findings indicate that substantial savings could be realised in terms of travel time, user cost, and operating cost to taxi passengers and drivers without additional costs being incurred by other road users. The single-lane pre-signal strategy, the queue-jumping lane and the dedicated taxi lane saw a decrease in total hourly cost of 12%, 14% and 30% respectively, including construction cost, user cost, and agency cost, indicating a net social benefit. If part of these savings were passed on to passengers, priority infrastructure could serve as an implicit subsidy to public transport users. [ABSTRACT FROM AUTHOR]

This paper proposes a modeling framework to design an integrated mobility service system that is composed of a local demand-responsive transportation (DRT) component and a fixed-route transit network component. The region is partitioned into disjoint local zones, and a trip is characterized into an intra- or inter-zonal one based on whether its origin and destination belong to the same zone. The transit network provides backbone line-haul service to inter-zonal trips, while the DRT system targets intra-zonal trips as well as the first-mile and last-mile legs of inter-zonal trips. The system components can be broadly defined, and this paper considers, as examples, conventional non-shared taxi or ride-sharing for the DRT service, and regular bus, bus rapid transit (BRT), or metro for the backbone network. For quantitative analysis of the DRT services, new aspatial queuing network models are developed to capture various DRT operations for serving trips with randomly distributed origins and destinations (i.e., intra-zonal trips) and those with origins or destinations concentrated at a set of fixed transit stations (i.e., first- or last-mile trip legs) at the same time. Each queuing model is integrated with the transit network design model, through proper service region partition, to derive closed-form formulas for the agency and passenger costs. Then, we formulate constrained non-linear programs that simultaneously optimize the zone partition, the fleet size and repositioning operation for the local DRT service, as well as the spacing and headway of a grid transit network. We apply the proposed models to a variety of transit technologies and application scenarios, so as to demonstrate applicability of the models, and to show promising performance of the proposed systems. • Integrated mobility systems containing a backbone transit network and a local DRT system. • New aspatial queuing models for local DRT operations that provide local and feeder services. • Closed-form formulas that connect DRT fleet size to expected level of service. • Insights on various key system parameters' impacts on the optimal design. • Demonstrated advantages of the proposed mobility systems over traditional counterparts. [ABSTRACT FROM AUTHOR]

• A continuum approx model for Open and Closed BRT operational schemes is formulated. • The model is adapted and solved for Valdivia (Chile), yielding comparative indicators. • The results of the model are applied to the topography and road network of Valdivia. • An estimation of the impact of both schemes for a real case is provided. • According to the model, an Open BRT should be preferable for the context of this city. Bus Rapid Transit (BRT) has proven to be an effective and affordable transportation option for large-sized cities. In these cities, BRT is usually considered an effective complement or substitute for rail-based systems, playing a key role in complex multimodal networks with several massive transport corridors. More recently, medium-sized cities of less than 200,000 inhabitants have also considering implementing BRT as a means of mass transit. These cities usually need only a few of these massive transport corridors (often just one), and they must decide how to structure their services. This report discusses which of the two types of BRT-based networks is best for the social interest in the case of medium-sized cities: (1) Closed BRT, in which buses operating inside and outside the corridor are separated and have different designs, or (2) Open BRT, in which the same buses operate inside and outside the corridor, entering and exiting at different points along a route. To answer this question two models with different levels of detail in terms of a city's characteristics were developed to represent both agency and user costs. In the first model a classic idealized city approach is addressed, while in the second model the problem is solved for the specific geographic characteristics and constraints of a real city. The results based on both models show that when it is optimally configured, Closed BRT networks offer mid-sized cities higher frequencies and lower waiting times. However, these benefits do not offset the cost associated with higher number of transfers that Closed BRT networks require, as compared to Open BRT networks. Transfers not only affect users due to the transferring experience, but also end up making the entire system slower. Overall, Open BRT shows significantly less Total Costs than Closed BRT in most of the scenarios that were analyzed. [ABSTRACT FROM AUTHOR]

• The impact of route choice modeling on transit system performances is examined. • Optimal user costs are affected by route choice modeling, but agency costs are not. • The system design is often insensitive to route choice modeling. • Details of route choice are generally negligible, yet notable exceptions exist. Sketchy design models are used to examine the fundamental tradeoff in transit systems and to guide high-level decisions. Traditionally, passengers' route choice is greatly simplified in such models. This study aims to understand whether this simplification would compromise qualitatively the results expected from the sketchy models. To this end, three transit systems, which all offer competitive alternative routes, are analyzed using the continuous approximation approach. We test what the impact on transit system performance (e.g. optimal designs and system costs) would be if travelers somehow split between these routes, rather than concentrate on the "best" one. A random utility model is employed to enable a probabilistic assignment of passengers to different routes according to the "perceived" utility. Analytical methods are then developed to estimate the aggregate share of each route in each system, based on which the user cost is obtained. Numerical results show that, while stochastic route choice modestly increases the optimal user cost, it has a negligible effect on the agency cost. Furthermore, the actual system design is largely insensitive to route choice modeling. Thus, while the simplest deterministic route choice assumption may not be valid in all systems, transit planners can safely ignore route choice details in most cases, at least for the purpose of strategic planning. [ABSTRACT FROM AUTHOR]

This paper extends the discussion about the bus network design in face of the mobility patterns associated with different degrees of urban dispersion. Based on an analytical approach, a comparison of total costs among different network structures is made for a ring-radial city, which is the other most common regular city layout. The results clarify what structure is the best solution for different scenarios of dispersion and city and transport characteristics. Simultaneously, the effect of the street pattern on the applicability of each structure is evaluated comparing these results to a previous research for a grid city. Three basic structures are analyzed: a radial scheme, a direct-trip-based network, and a hybrid structure as a transfer-based alternative. Each structure is dominant for a specific range of dispersion: radial networks for scenarios of high concentration, direct-trip-based systems for intermediate degrees of dispersion, and transfer-based structures when the activities are decentralized. However, constraints on stop capacity modify these ranges. Each structure presents a different distribution of travel time in the transit chain and agency costs that determine the most competitive alternative. In addition, the behavior of the structures and the evolution of costs regarding urban decentralization are practically the same for both street patterns: system costs grow with increasing mobility dispersion, the range of applicability for each structure is the same, and changes in their applicability when main input parameters vary are very similar. Therefore, these results make it possible to generalize about the conclusions obtained independently of the street layout. [ABSTRACT FROM AUTHOR]

• The basic trade-off in six distinctive transit systems is examined. • Ride-pooling is unlikely to change the economy of scale in transit design. • Ride-pooling promises modest improvements to the overall system efficiency. • Ride-pooling tilts the balance of trade-off in the user's favor. This paper examines the basic design trade-off in six distinctive transit systems, including two state-of-the-art fixed-route systems and four hybrid systems that use ride-pooling as an integrated feeder service. The systems are analyzed using a continuous approximation approach, and the resulting optimal design problem is formulated and solved as a mixed integer program. We find that ride-pooling changes little the fundamental laws inherent in transit design. Specifically, all six systems, despite their seemingly vastly different design features, display the following laws: (1) that the per capita agency cost correlates linearly with the per capita user cost, (2) that both costs are power functions of the demand density with an exponent close to − 1 3 and − 0.4 for agency and user costs, respectively, and (3) that the per capita agency cost is not significantly affected by city size but the user cost is. This finding suggests that ride-pooling may have a rather limited impact on the economy of scale in mass transit systems. However, mixing ride-pooling with fixed-route services does promise modest improvements to the overall system efficiency. It also tilts the balance of trade-off considerably in the user's favor, at the operator's expense. [ABSTRACT FROM AUTHOR]

Cities worldwide are deploying electric buses rapidly to enhance eco-friendly public transportation. Most existing electric transit systems rely solely on stationary charging at terminals and have to equip buses with large-sized batteries to maintain operation in networks. Consequently, the stationary-charging electric bus (SE-Bus) systems are subject to high battery costs, limited range per charge, long charging time (layover time), etc. These limitations may be addressed by integrating the new wireless power transfer technology, which provides contactless charging to the operating buses without extra delays. To guide wireless-charging electric bus (WE-Bus) designs in corridors, this paper proposes an optimization model to jointly optimize (i) the electric supply system and (ii) the transit service that are interdependent. Specifically, we construct parsimonious models for system metrics using five design variables/functions, i.e., battery size, the number of wireless power transfer (WPT) pads, stationary charging rate, service headways, and stop densities. Accordingly, we formulate the optimal design problem to minimize the generalized system cost as the sum of the transit agency's and patrons' costs. The problem is attacked by first decomposing into two sub-problems regarding (i) electric supply system design and (ii) transit service design and then solving them iteratively. The (i) sub-problem is converted to a linear programming problem by linearization, and the (ii) sub-problem is analyzed with optimal conditions. Numerical tests show the proposed solution approach produces accurate results. Extensive numerical experiments unveil several findings. First, the WE-Bus systems outperform the SE-Bus in various scenarios except when wireless charging facilities are too costly. Second, the optimized WE-Bus designs can reduce costs not only to the agency (with smaller-sized bus battery and reduced fleet cost) but also to patrons (who enjoy improved services with shorter headways). Additional parameter analyses also investigate the impacts of demand levels, wireless charging rates, depths of discharge, etc. Lastly, a case study in Chengdu (China) illustrates the application of the proposed model. • Models are built for wireless-charging electric bus (WE-Bus) designs. • The electric system and the transit service are jointly optimized. • WE-Bus systems show a wide range of application. • Optimized WE-Bus designs may save costs for the agency and transit patrons. [ABSTRACT FROM AUTHOR]

[Display omitted] In most cities, transit consists solely of fixed-route transportation, whence the inherent limited Quality of Service for travellers in suburban areas and during off-peak periods. On the other hand, completely replacing fixed-route (FR) with demand-responsive (DR) transit would imply a huge operational cost. It is still unclear how to integrate DR transportation into current transit systems to take full advantage of it. We propose a Continuous Approximation model of a transit system that gets the best from fixed-route and DR transportation. Our model allows deciding whether to deploy a FR or a DR feeder, in each sub-region of an urban conurbation and each time of day, and to redesign the line frequencies and the stop spacing of the main trunk service. Since such a transit design can adapt to the spatial and temporal variation of the demand, we call it Adaptive Transit. Numerical results show that, with respect to conventional transit, Adaptive Transit significantly improves user-related cost, by drastically reducing access time to the main trunk service. Such benefits are particularly remarkable in the suburbs. Moreover, the generalized cost, including agency and user cost, is also reduced. These findings are also confirmed in scenarios with automated vehicles. Our model can assist in planning future-generation transit systems, able to improve urban mobility by appropriately combining fixed and DR transportation. [ABSTRACT FROM AUTHOR]

This paper presents design methods for a flexible-route transit system, in which vehicles travel within predetermined areas to provide door-to-door service. The main advantage of this system is that passengers no longer have to access transit stations in order to gain service. This system is suitable for low and heterogeneous passenger demand distribution as it features a hybrid system layout that includes both a hub-and-spoke network in the peripheral region and a grid network in the central region, along with heterogeneous local routes that address local demand variations. Continuum approximation (C.A.) is used to reduce the computation burden by formulating the design problem with respect to a few decision variables. We compare the performance of the proposed transit system with (i) the typical fixed-route system, (ii) the homogeneous flexible-route grid system, and (iii) the flexible-route grid system with local routes, in hypothetical settings. It is found through our numerical examples that the integration of the three proposed features (i.e. flexible transit, local tubes, and hybrid structure), as compared to counterparts with only two or fewer features, yields lower combined agency and user costs under the assumed low heterogeneous demand distribution. We then apply the design framework to a more realistic case for the City of Changzhi, China. An implementable design for Changzhi is developed, and its performance verified with simulations, demonstrating accuracy and applicability of the proposed continuum approximation model. • Flexible-route transit system for low and spatially heterogeneous demand. • Continuum approximation model to design hybrid network structure and local routes. • Schematic design translated into implementable design that conform with street networks. • Significant agency and user cost reduction as compared to traditional transit networks. • Simulations validate performance predictions for a real-world case study. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the network shapes and operating characteristics that allow a transit system to deliver an accessibility level competitive with that of the automobile. To provide exhaustive results for service regions of different sizes and demographics, the paper idealizes these regions as squares with uniform demand, and their possible networks as a broad and realistic family that combines the grid and the hub-and-spoke concepts. The paper also shows how to use these results to generate master plans of transit systems for real cities. The analysis reveals which network structure and technology (Bus, Bus Rapid Transit, or Metro) delivers the desired performance with the least cost. It is found that the more expensive the system’s infrastructure, the more it should tilt toward the hub-and-spoke concept. Bus Rapid Transit (BRT) competes effectively with the automobile unless a city is big and its demand low. This happens despite the uniform demand assumption, which penalizes collective transport. It is also found that if a city has enough suitable streets on which to run Bus and BRT systems, these outperform Metro even if the city is large and the demand high. Agency costs are always small compared with user costs; and both decline with the demand density. In all cases, increasing the spatial concentration of stops beyond a critical level increases both, the user and agency costs. Too much spatial coverage is counterproductive. [Copyright &y& Elsevier]

Socio-demographic trends and recent economic development patterns have resulted in travel behavior changes that call for more flexible and accessible public transit options. Because flexible transit services vary in scope, size, and service type, new data-informed methods are useful to optimize services based on the specific needs of local communities and riders. In this study, real-world demand and vehicle trajectory data were used to evaluate and optimize system performance for an existing first-mile–last-mile (FMLM) service in Robinson Township, PA. A general FMLM model for arbitrary demand and service supply was then developed to quantify system performance—both travel time costs and day-to-day reliability—for various operational polices considering spatio-temporal demand variation and transportation network dynamics. Heuristics were used for optimal real-time vehicle routing in sizable real-world networks accommodating various service types and scopes. In this case study, total user costs were reduced by 18.6% when rides were coordinated with mainline fixed-route transit. Predictive routing strategies were shown to marginally improve system performance under sparse and variable spatio-temporal demand. The case study also highlights potentially large travel time and user reliability improvements—reductions of 51% and 53.8%, respectively—when trip requests were made in advance of their desired pickup time. Finally, we show that travel time reliability can be improved for time-inflexible trips with trip prioritization without increasing total user costs. These results were stable to changes in demand density. • Develop a general FMLM service operation model for optimally match/route riders and vehicles in real time. • Evaluate and optimize strategic, tactical, and operational decisions for FMLM services. • Day-to-day reliability metrics are considered as one key performance metric. • Trade off among generalized user costs and agency cost under various scenarios. [ABSTRACT FROM AUTHOR]