U.S. Department of Transportation
    	Federal Highway Administration
        1200 New Jersey Avenue, SE
Washington, DC 20590
        202-366-4000
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
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| This report is an archived publication and may contain dated technical, contact, and link information | 
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Publication Number: FHWA-HRT-05-138 
  Date: July 2006  |