Piezoelectric sensors are being tested for collecting traffic data, including weigh-in-motion, measuring vehicle speeds, classifying vehicles by category and counting axles etc. There are two types of these sensors ? polymer and ceramic. Currently WIM systems use a piezoelectric polymer sensor that produces a voltage proportional to an applied pressure or load. The polymer sensors are usually in the form of a long tape or cable embedded within a long block of elastomeric material. These blocks are installed into grooves, which are cut into roads perpendicular to the traffic flow.

As the world economy continues to grow, and the law of comparative economic
advantage takes on greater significance at both the national and regional level, the
importance of having efficient and effective freight transportation systems continues to
increase. Local economies are no longer immune, or insensitive to shifts in trading patterns
and alliances on the global level. A region that is strategically placed geographically, and
well-equipped from a freight transportation system standpoint, will profit significantly from

<p>This document contributes to such a regional-level (freight) network planning effort by presenting a methodology whereby alternative network improvement options can be tested, evaluated, refined, and compared in an effort to identify the best long-run and shortterm strategies. The purpose is to provide a tool that metropolitan planning organizations (MPOs), state departments of transportation, and other similar agencies can use for such purposes.

The main objective of this report is to conduct an assessment of the different freight
transportation modeling methodologies. The report begins with a definition of the main
objectives and scope of the regional freight model, followed by a discussion of the main freight
transportation issues in the NYMTC region, and the potential role of the regional freight model.
The main methodological alternatives are discussed next. This includes a brief description of the