Cross-cutting Issues

Increasing amounts of traffic, congestion, pollution and changes in the climate causing hazardous
weather and road conditions are reasons for a growing need for advanced real-time traffic-related
information systems and services. This paper presents the CARLINK 0 (Wireless Platform for Linking
Cars) project. The aim of the project has been to develop an intelligent wireless traffic service platform
between cars supported with wireless transceivers beside the road(s). The main outcomes of the project
are: an intelligent wireless traffic service platform, real-time local road weather and traffic data
applications, urban transport traffic management and information broadcasting/sharing applications,
fast connectivity and routing schemes for ad- hoc networking and hands/eyes free applications that
enable the driver to interact with the information system. The preliminary network simulations,
communication tests and weather service prototypes have already shown that a new kind of wireless
communication environment can be created and it is, indeed, capable of enhancing traffic safety. The
CARLINK results support other related projects such as COMeSafety, CVIS, SAFESPOT and
COOPERS.

Finnish Meteorological Institute

Mobisoft Oy, Finland

Sunit Oy, Finland

Presented at the 15th World Congress on Intelligent Transport Systems, November 16-20, 2008, New York, New York

Efficient storage, processing and communication of dynamic data are at the heart of Intelligent Transportation Systems (ITS) applications. The speed of communication and processing as well as the storage space required by such data depend on the method used for its representation. ITS applications typically involve dynamic data that is discrete and require fast computation and communication to support real-time operations. In this paper, we present an efficient representation method, which we call the bit-stream representation, for discrete-time dynamic data. We illustrate its positive impacts by developing efficient representations for storage and communication of travel times in dynamic transportation networks. We show theoretically that this representation method typically leads to an L/2-fold gain in both storage space and in communication speed as compared to methods that represent discrete-time dynamic data using L-bits to store an integer. The bit-stream representation method also opens new horizons in the research and development of algorithms that operate on dynamic data and holds the potential to discover a new generation of fast algorithms.

Massachusetts Institute of Technology

Presented at the 10th ITS Annual Conference and Exposition, May 1-4, 2000 Boston, MA

The Alaska Department of Transportation and Public Facilities (ADOT&PF) is deploying a statewide Road Weather Information Systems (RWIS) network as part of their regional Intelligent Transportation Systems (ITS) architecture, the Alaska Iways Architecture Implementation (AI2). In Phase I, ADOT&PF installed 8 RWIS sites in the Anchorage area as a prototype to establish the type of equipment, site construction standards, and operational issues for future RWIS installations. Phase II calls for up to 31 additional RWIS in some of Alaska’s most remote and extreme weather prone areas of the surface transportation network.

Alaska DOT

Presented at the ITS America Annual Conference and Exposition, May 19-22, 2003 Minneapolis, Minnesota

This paper demonstrates the use of a sketch model, Tool for Rush-Hour User Charge Evaluation (TRUCE), to evaluate the costs, revenues, and congestion reduction benefits that congestion pricing scenarios could generate in four metropolitan regions in the United States. The paper gives a general overview of congestion pricing and its benefits. It describes system design and costs for four pricing scenarios that employ different methods of congestion pricing and management strategies and presents estimates of system revenue and future net benefits for each scenario. The model recognizes that each urban area is different and should be addressed with its own unique solutions based on the level of congestion, population density, size, geographical layout of the highway/arterial network and travel patterns. The scenarios result in different types of revenue generation, traffic impacts and congestion relief showing that congestion pricing can be a viable source of revenue while providing an effective mechanism for metropolitan areas to manage worsening congestion.

Federal Highway Administration

Booz Allen Hamilton

D’Artagnan Consulting

Paper submitted for publication and presentation at the ITS America’s 2009 Annual Meeting and Exposition

The U.S. Government and the automotive industry have been developing prototype systems to evaluate the effectiveness of using Dedicated Short Range Communications (DSRC) to support vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) safety applications. Many V2V safety applications rely on each vehicle periodically broadcasting a Basic Safety Message (BSM) at a sufficient interval to provide an accurate representation to surrounding vehicles about the transmitter’s current position, speed, heading, and other critical information. Unfortunately, as the number of vehicles in communication range increases, the ability for each vehicle to reliably receive messages decreases due to packet collisions on the wireless medium. This paper describes an algorithm to dynamically adapt the BSM message transmission rate based on the wireless congestion level. Simulation and test results using real DSRC radios are provided showing the benefits of the algorithm.

Authors Aaron Weinfield, John B. Kenney, Gaurav Bansal

Presented at the 18th World Congress on ITS, October 2011, Orlando, Florida