2013 Session: 226

• Estimating Transit Route-level OD Flow Matrices from APC Data on Multiple Bus Trips Using the IPF Method with an Iteratively Improved Base
  Abstract: An iterative method is proposed to estimate bus route-level origin-destination (OD) passenger flow matrices from boarding and alighting data for time-of-day periods in the absence of good a priori estimates of the flows. The algorithm is based on the widely used Iterative Proportional Fitting (IPF) method and takes advantage of the large quantities of boarding and alighting data that are routinely collected by transit agencies using Automatic Passenger Counter (APC) technologies. An arbitrarily chosen OD matrix is used as the base matrix required to initialize the algorithm, and the IPF method is applied with trip-level boarding and alighting data and the base matrix to produce an estimate of the OD flow matrix for each trip. The trip level OD flow matrices are then aggregated to produce an estimate of the period-level OD flow matrix, which in turn is used as the base matrix for the following iteration until convergence.Empirical results are conducted on operational bus routes using APC data collected during multiple quarters where directly observed OD passenger flows are available to represent the ground-truth. In all cases where APC data are available for even a reasonably small number of bus trips, the developed method produces better estimates than the traditional application of the IPF method when using the uninformative null matrix as the base without updating. Moreover, the algorithm converges in minimal computational time, and the estimates are seen to be insensitive to the OD flow matrix used to initialize the algorithm.
  Authors: Ji, Yuxiong; Mishalani, Rabi G.; McCord, Mark R.
  Authors: Ji, Yuxiong; Mishalani, Rabi G.; McCord, Mark R.
  Year: 2013
  Document Type: Paper
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-3375
• Designing Bus Rapid Transit Facilities for Constrained Urban Arterials: A Case Study of the Webster Avenue SBS Running Way Design Selection Process
  Abstract: Providing Bus Rapid Transit (BRT) service on urban arterials can be a challenge for transportation agencies as they look to provide transit benefits within existing street infrastructure. Projects must provide high quality transit service while also supporting other important street needs such as pedestrian activity, traffic flow, on-street parking, and crash safety. Transportation agencies must make tradeoffs across different designs in ways that achieve a project’s goals but do not mire the early planning for the project in unneeded costs and delays. This paper describes the New York City Department of Transportation and MTA New York City Transit’s selection of the most appropriate on-street BRT running way design for Webster Avenue (US 1), a key north-south arterial in the central Bronx, based on a balanced, multi-modal set of criteria. Three BRT running way design alternatives - curbside, offset, and median bus lanes - were considered for Webster Avenue’s 70-foot wide right-of-way during the screening process. The four primary screening categories were transit operations, traffic operations, on-street parking / delivery curb space supply, and pedestrian benefits. Each design alternative was evaluated at two sample intersections that represented typical corridor conditions and the results were then expanded to provide a complete corridor evaluation. The evaluation found that the offset bus lane alternative most effectively balanced the transit and traffic needs along the Webster Avenue corridor while maintaining on-street parking and supporting pedestrian activity, making it the preferred corridor design.
  Authors: Beaton, Eric; Orosz, Theodore; Ernhofer, Oliver J.; Yuratovac, Donald; Reiss, Taylor; Bialostozky, Evan
  Authors: Beaton, Eric; Orosz, Theodore; Ernhofer, Oliver J.; Yuratovac, Donald; Reiss, Taylor; Bialostozky, Evan
  Year: 2013
  Document Type: Paper
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-1346
  Practice-Ready: Yes
• Benefits of Standardization of Bus Transit Automated Vehicle Location Data Outputs to the Academic Community
  Abstract: Automatic Vehicle Location (AVL) systems offer transit agencies and the academic community vast quantities of data on the operation of bus transit networks. However turning this raw data into useful metrics that are of interest can be quite cumbersome and require a significant amount of processing of AVL log files. There would be many benefits to both transit agencies and academia if such metrics were output in a standardised format by the AVL system.This paper summarises existing data exchange standards used in the bus transit industry and explains the benefits of these. It then describes a recent project undertaken by London Buses to analyse dwell time data, and highlights the difficulties and costs involved collecting the basic data required for this analysis. It proposes that more data standards should be defined for data output by AVL systems. If these standards were then implemented by AVL vendors this would mean that transit agencies and academics could get easy access to useful information which otherwise would require much time and cost in obtaining.
  Authors: Robinson, Stephen
  Authors: Robinson, Stephen
  Year: 2013
  Document Type: Paper
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-2811
  Practice-Ready: Yes
• Simulation-Based Planning Framework for Choosing Where to Implement Bus Signal Priority in Mixed-Mode Operations
  Abstract: Planning is the first phase in a systematic approach towards a better implementation for Bus Signal Priority (BSP), and is required by the U.S. Department of Transportation as the first step of a standard system engineering approach for any federally funded ITS project. Numerous studies have focused on various aspects of BSP design and operation; however, less attention is paid to the planning phase of a BSP project. This study concentrates directly on planning for a BSP implementation project. The proposed framework is entirely based on micro-simulation; it requires a basic concept design for the BSP system which is under planning. This concept design should be available from the planning steps that precede the choosing of intersections that should be equipped with a BSP. The framework evaluates different scenarios for BSP at individual intersections by looking at their marginal impact on the entire network and on the intersection. At last, the intersection-level scenarios that result in the maximum total marginal improvement are selected for BSP implementation. The final output of the framework, provides information on which intersections should be equipped with BSP, and which bus lines are eligible to receive this priority at each intersection. The proposed framework is demonstrated on the network of downtown Dover, DE. An 18% savings in network average bus delay and no significant disbenefit to automobile traffic are achieved. The benefits translate into rough minimum savings of $0.25M per year just by implementing this framework during a peak traffic hour.
  Authors: Tabatabaie Shourijeh, Morteza; Faghri, Ardeshir; Stevanovic, Aleksandar
  Authors: Tabatabaie Shourijeh, Morteza; Faghri, Ardeshir; Stevanovic, Aleksandar
  Year: 2013
  Document Type: Paper
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-4460
  Practice-Ready: Yes
• Designing Bus Rapid Transit Facilities for Constrained Urban Arterials: A Case Study of the Webster Avenue SBS Running Way Design Selection Process
  Authors: Beaton, Eric
  Authors: Beaton, Eric
  Year: 2013
  Document Type: Presentation
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-1346
• Estimating Transit Route-level OD Flow Matrices from APC Data on Multiple Bus Trips Using the IPF Method with an Iteratively Improved Base
  Authors: Mishalani, Rabi
  Authors: Mishalani, Rabi
  Year: 2013
  Document Type: Presentation
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-3375
• Benefits of Standardization of Bus Transit Automated Vehicle Location Data Outputs to the Academic Community
  Authors: Robinson, Stephen
  Authors: Robinson, Stephen
  Year: 2013
  Document Type: Presentation
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-2811
• Simulation-Based Planning Framework for Choosing Where to Implement Bus Signal Priority in Mixed-Mode Operations
  Authors: Tabatabaie Shourijeh, Morteza
  Authors: Tabatabaie Shourijeh, Morteza
  Year: 2013
  Document Type: Presentation
  Subject: Passenger Transportation; Public Transportation
  Session: 226
  Paper Number: 13-4460