SAV Operations on a Bus Line Corridor: Travel Demand, Service Frequency, and Vehicle Size

Before shared automated vehicles (SAVs) can be widely adopted, they are anticipated to be implemented commercially in confined regions or fixed routes where the benefits of automation can be realized. SAVs have the potential to operate in a traditional transit corridor, replacing conventional transit vehicles, and have frequent interactions with riders and other vehicles sharing the same right of way. This paper microsimulates SAVs’ operation on a 6.5-mile corridor to understand how vehicle size and attributes of such SAV-based transit affect traffic, transit riders, and system costs. The SUMO (Simulation of Urban MObility) platform is employed to model microscopic interactions among SAVs, transit passengers, and other traffic. Results show that the use of smaller, but more frequent, SAVs leads to reduced passenger waiting times but increased vehicle travel times. More frequent services of smaller SAVs do not, in general, significantly affect general traffic due to shorter dwell times. Overall, using smaller SAVs instead of the large 40-seat SAVs can reduce system costs by up to 4% while also reducing passenger waiting times, under various demand levels and passenger loading factors. However, the use of 5-seat SAVs does not always have the lowest system costs.

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Adaptation of Time Use Patterns to Simulated Travel Times in a Travel Demand Model

Progress in Activity-Based Analysis ◽

10.1016/b978-008044581-6/50011-9 ◽

2005 ◽

pp. 161-174

Author(s):

Georg Hertkorn ◽

Peter Wagner

Keyword(s):

Time Use ◽

Travel Demand ◽

Travel Times ◽

Demand Model ◽

Use Patterns ◽

Travel Demand Model

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A Stop-Probability Approach for O-D Service Frequency on High-Speed Railway Lines

Sustainability ◽

10.3390/su11246996 ◽

2019 ◽

Vol 11 (24) ◽

pp. 6996

Author(s):

Shuo Zhao ◽

Xiwei Mi ◽

Zhenyi Li

Keyword(s):

High Speed ◽

Travel Demand ◽

Mathematical Formulation ◽

Real Life ◽

Point Of View ◽

High Speed Railway ◽

Passenger Travel ◽

Optimal Service ◽

Service Frequency ◽

Railway Operation

Train stop planning provides appropriate service for travel demand and stations and plays a significant role in railway operation. This paper formulates stop planning from the point of view of direct travel between origin-destination (O-D) stations and proposes an analytical method to theoretically derive optimal service frequencies for O-D demand on different levels. Considering different O-D demand characteristics and train service types, we introduce the concept of stop probability to present the mathematical formulation for stop planning with the objective of minimizing per capita travel time, which is solved by an iterative algorithm combined with local search. The resulting optimal stop probabilities can be used to calculate the required service frequency for each train type serving different demand categories. Numerical examples, based on three real-life high-speed railway lines, demonstrate the validity of the proposed method. The proposed approach provides a more flexible and practical way for stop planning that explicitly takes into account the importance of different stations and passenger travel characteristics.

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Feeder Bus Accessibility Modeling and Evaluation

Sustainability ◽

10.3390/su12218942 ◽

2020 ◽

Vol 12 (21) ◽

pp. 8942

Author(s):

Shixiong Jiang ◽

Wei Guan ◽

Liu Yang ◽

Wenyi Zhang

Keyword(s):

Travel Time ◽

Public Transportation ◽

Analytical Modeling ◽

Travel Demand ◽

Travel Times ◽

Simulation Experiments ◽

Last Mile ◽

Feeder Bus ◽

Travel Services ◽

Demand Responsive Transit

To improve first/last mile travel services between metro stations and communities, this study modeled and analyzed four kinds of feeder bus operation strategies in terms of travel time and accessibility. The analytical modeling was used to compare the travel times and the simulation experiments were used to compare the accessibilities of different operation strategies. The results showed that when the ratio between length and width of study area increases, the number of stops for the fixed route transit with fixed stops will increase. When the travel demand is low, the demand responsive transit with separate routes has the highest accessibility. When the travel demand is high, the fixed route transit with fixed stops provides the highest accessibility. In addition, the ratio of flows in two passenger directions has different influences on the four operation strategies. This study can provide guidance for feeder bus operation to improve public transportation attraction.

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Urban Mobility and City Logistics – Trends and Case Study

PROMET - Traffic&Transportation ◽

10.7307/ptt.v30i5.2825 ◽

2018 ◽

Vol 30 (5) ◽

pp. 613-622 ◽

Cited By ~ 4

Author(s):

Rodrigo Rezende Amaral ◽

Ivana Šemanjski ◽

Sidharta Gautama ◽

El-Houssaine Aghezzaf

Keyword(s):

Public Health ◽

Air Pollution ◽

Sustainable Development ◽

Traffic Management ◽

City Logistics ◽

Urban Mobility ◽

Travel Times ◽

The Sustainable Development ◽

Goods And Services

Improving urban mobility is crucial to the sustainable development of a city. Well-managed movement of individuals, goods, and services is essential to increase citizens’ welfare, not only by reducing travel times and congestion levels, but also by minimizing air pollution, noise, accidents, etc. To achieve the desired results, the objectives and scope of the optimization efforts have become broader in recent years. Instead of focusing only on the flows and on the network itself, research and projects have connected various areas of economy to traffic management, such as public health and logistic optimization. In this work we discuss the interconnections between urban mobility and city logistics, and present a case study showing how the mobility plan implemented in Ghent (Belgium) in April 2017 affected its logistic system.

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Behavioral strategies of automated vehicles in critical right of way situations on intersections

at - Automatisierungstechnik ◽

10.1515/auto-2014-1134 ◽

2015 ◽

Vol 63 (3) ◽

Author(s):

Alexander Stoff ◽

Hermann Winner

Keyword(s):

Collision Avoidance ◽

Behavioral Strategies ◽

Automated Vehicles ◽

Right Of Way ◽

Road Users ◽

Safety Function ◽

Potential Safety ◽

Avoidance Strategies ◽

The Right

AbstractThis paper analyzes and evaluates alternative options for action and earliest possible dates for intervention for an automated safety function to avoid or mitigate collisions in priority situations in which the right of way regulations are violated by the crossing road users. Based on a simulation of the collision avoidance strategies, the potential safety benefits could be predicted.

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Obtaining Public Transport Level-of-Service Measures Using In-Vehicle GPS Data and Freely Available GIS Web-Based Tools

Advances in Data Mining and Database Management - Mobile Technologies for Activity-Travel Data Collection and Analysis ◽

10.4018/978-1-4666-6170-7.ch016 ◽

2014 ◽

pp. 258-275 ◽

Cited By ~ 1

Author(s):

Julián Arellana ◽

Juan de Dios Ortúzar ◽

Luis I. Rizzi ◽

Felipe Zuñiga

Keyword(s):

Public Transport ◽

Low Cost ◽

Waiting Times ◽

Geographic Location ◽

Level Of Service ◽

Gps Data ◽

Travel Times ◽

Public Transport System ◽

Bus Stops ◽

Bus Networks

In this chapter, the authors present a procedure to obtain some Level-Of-Service (LOS) measures, such as waiting times, travel times, and their variability, at any spatial and temporal aggregation level for dense bus networks using freely available map and geographic software. The proposed methodology is highly flexible, as it can accommodate either fixed or variable space-time aggregations. It can handle vast amounts of GPS data yielding LOS results relatively quickly. Furthermore, it can be implemented at relatively low cost in terms of software requirements using freely available software. An illustration of the proposed procedure and its results to obtain LOS measures such as travel times and their variability among bus stops and waiting times for every bus stop are reported using the geographic location of bus stops and offline GPS data available (every 30 seconds) for all operating buses in Santiago´s public transport system.

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Evaluation of Bus Reliability Measures and Development of a New Composite Indicator

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2533-10 ◽

2015 ◽

Vol 2533 (1) ◽

pp. 91-99 ◽

Cited By ~ 7

Author(s):

Antonio Gittens ◽

Amer Shalaby

Keyword(s):

User Behavior ◽

Waiting Times ◽

Linear Regression Analysis ◽

Time Of Day ◽

Travel Times ◽

City Center ◽

Route Length ◽

Time Buffer ◽

Stop Spacing ◽

The City

Reliability is cited as a key aspect of service quality, but many of the indicators in use today do not measure reliability from the user's perspective. A review of earlier work on transit user behavior concluded that the traveler's perspective of reliability was driven by punctuality in arriving at the destination, short waiting times at the origin stop, and consistent wait and travel times. Twenty indicators were assessed, but none were well suited to capturing all of these elements of reliability. A new measure, journey time buffer index (JTBI), was therefore proposed; the index used estimates of wait times at bus stops while capturing variability in wait and travel times that tended to increase the disutility of transit travel. Alternative formulations were developed for short and long headway service, and the new indicator was applied to the London Transit Commission's bus network in London, Ontario, Canada. This procedure demonstrated that the JTBI was better suited to identifying the factors contributing to unreliable service than metrics that focused on a single component of reliability. A linear regression analysis also highlighted that route length, stop spacing, time of day, route orientation relative to the city center, and passenger load all influenced reliability although the low adjusted R2 value of .298 showed that some major causes of reliability were not captured by the model.

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