Travel Behavior

Personalized Demand Responsive Transit Systems

Yim, Y. B.
Khattak, Asad J.
2000

An aging population in the US, low-density urban sprawl and the accessibility needs of certain groups (particularly disabled and aged) increasingly point to more flexible demand-responsive transit systems in the future. This paper describes the important aspects of a consumer-oriented Personalized Demand Responsive Transit (PDRT) service. The system will provide services to the traveling public for journeys to work and for journeys to other destinations. A PDRT that responds to the travelers' needs and takes advantage of the emerging advanced public transportation technologies to increase...

Incident Management: Process Analysis And Improvement Phase 1: Review Of Procedures

Hall, Randolph
Mehta, Yatrik
1998

This working paper examines the process for managing incidents on highways, as it is applied in Los Angeles County. The examination is based on interviews with various agencies, including law enforcement, state highway department, coroners office, and LA County MTA Freeway Service Patrol, along with direct observation through ride-alongs. Follow-up work will quantify the benefits of improved incident management, through analysis of freeway performance and response characteristics during incidents.

Estimation Of Travel Time Distribution And Detection Of Incidents Based On Automatic Vehicle Classificatin

Anatharam, V.
1998

We study the problem of travel time estimation along a section of a freeway based on data derived from vehicle detectors at multiple locations. We pose the problem as one of pattern recognition. We derive algorithms that aim to recognize patterns which persist between the error-prone upstream detector samples and the error-prone downstream detector samples. We describe how these can allow us to estimate the distribution of the travel time between these detector locations. The most promising algorithm derived in this research is a dynamic programming based algorithm based on sequence...

Ideal Dynamic User-Optimal Route Choice: A Link-Based Variational Inequality Formulation

Ran, Bin
Boyce, David E.
1995

The ideal dynamic user-optimal (DUO) route choice problem is to determine vehicle flows on each link at each instant of time resulting from drivers using actual minimal-time routes. Actual route time is the travel time incurred while driving along the route. In a previous paper, we presented a route-based optimal control model for the ideal DUO route choice problem. However, this model is not appropriate for largescale transportation networks because some degree of route enumeration is necessary to solve the model. In this paper, we first present the traffic network constraints and link-...

An Enhancement to Speed Estimation with Single Loops

Lin, Wei-Hua
Dahlgren, Joy
Huo, Hong
2003

Traffic data from single loop detectors are one of the dominant data sources widely used in many traffic operation centers and traveler information systems. Speed estimation from single loop detectors is mainly based on occupancy data, a conversion factor from occupancy to density (which is related to vehicle length), and the assumed relationship between flow, speed, and density. This paper investigates the discrepancy between the speed estimated with single loops and the speed measured directly from double loops. It was found that the inaccuracy of speed estimation with single loops is...

Evaluation of UC Davis Long-Range Transportation, Land-Use, and Housing Plans: Examining the Potential for Innovative Mobility Pilot Projects

Finson, Rachel S.
Shaheen, Susan A.
2001

At present, the City of Davis, surrounding communities, and the UC Davis campus are struggling with many of the same transportation problems that plague larger urban centers including increasing traffic, limited parking, and challenges to effective operation of the public transit system. The campus is expecting to grow by 6,000 students in the next ten years (plus approximately 3,000 faculty and staff) and is developing a Long-Range Development Plan (LRDP) that will serve to guide this growth. This plan will include housing, traffic control, parking, alternative transportation modes, and...

Adaptive Signal Control System with On-line Performance Measure for Single Intersection

Liu, Henry X.
Oh, Jun-Seok
Recker, Will
2002

This paper introduces an adaptive signal control system utilizing an on-line signal performance measure. Unlike conventional signal control systems, the proposed method employs real-time delay estimation and an on-line signal timing update algorithm. As a signal performance measure, intersection delay for each phase is measured in real-time via an advanced surveillance system that re-identifies individual vehicles both at upstream and downstream stations using vehicle waveforms obtained from advanced inductive loop detectors. In each cycle, the signal timing plan is optimized based on the...

Vehicles As Probes

Sanwal, Kumud K.
Walrand, Jean
1995

In this paper, the authors discuss the use of vehicles moving in traffic as probes that provide data for estimation and prediction of traffic behavior. The probe vehicles can report data on their speeds, locations, or travel times which can be used by an algorithm that updates estimates of traffic state and makes predictions for the future. The authors address some of the key issues involved in the design of such a traffic monitoring system.

TravInfo Evaluation: Traveler Response Element Broad Area Study: Phase 2 Results Analysis of Wave-2 Survey

Yim, Y. B.
2001

TravInfo was a Field Operational Test (FOT) sponsored by the Federal Highway Administration (FHWA) and California Department of Transportation. It aimed to develop a multi-modal traveler information system for the San Francisco Bay Area, combining public and private sector talents. The Broad Area Study was part of the TravInfo FOT evaluation. It addressed issues on how travelers obtain traffic/transit information and how the information influences travel behavior. Two waves of telephone surveys of Bay Area households were conducted, one prior to and one after the Field Operational Test....

TravInfo Evaluation Plan: Update 1

Yim, Youngbin
Khattak, Asad
Miller, Mark
Hall, Randolph
Weissenberger, Stein
1994

TravInfo is a public/private partnership formed to provide wide-spread dissemination of real-time information on transportation conditions and travel options. A fundamental premise is that a public surveillance and database system, designed to open-architecture standards, will be an effective stimulus for private sector innovations in ATIS (Advanced Traveler Information Systems) technologies and, ultimately, their deployment.TravInfo is a Field Operational Test of a centralized database providing easy access to real-time travel information on all modes of transportation in the Bay Area....