摘要: |
In 1992 the Oregon Department of Transportation undertook an operational test of the Port-of-Entry Advanced Sorting System (PASS), which uses a two-way communication automatic vehicle identification system, integrated with weigh-in-motion, automatic vehicle classification, and over-height detection tied into a heavy vehicle database. The purpose of this operational test was to demonstrate the feasibility of using this system to let trucks directly bypass the port and the static scale weighing process, thus resulting in significant benefits for both the carriers and the State. An additional purpose was to test the use of "double-threshold" bending plate type weigh-in-motion scales to improve the weighing accuracy as compared to single weigh-in-motion scales. In this Final Report, the authors describe the PASS system and present results obtained from three years of operation. Results from a survey of trucking firms are presented. Results from the testing of the double-threshold weigh-in-motion scales are also presented and discussed. Some problems with the state-of-the-art PASS occurred, causing interruptions. Most were software problems, which were resolved. The survey indicated that truckers and trucking firms using the two-way transponders were pleased with the system. The project proved that the mainline sorting of heavy vehicles to bypass or enter a Port-of-Entry is workable with current technology. The variability of weight measurements using the double-threshold weigh-in-motion scales was found to be less than the variability of measurements from the twin weigh-in-motion scales when taken separately. Unfortunately, the weights provided by the WIM scales appeared to be biased toward the mean in spite of careful calibration. Thus the value of double-threshold WIM scales remains unclear. |