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From page 18... ... Table 3 lists novel IPM system applications, identified primarily through the transportation practitioner survey and the IPM system vendor survey. WARNING With the primary intent to warn road users, IPM systems have been implemented -- as an isolated system or in combination with other warning devices -- in school zones, in construction zones, at highway–rail crossings, along horizontal curves, and in areas that experience frequent adverse weather. Read the entire page →
From page 19... ... . Researchers noted that the devices that were the most effective based on the Application Source Warning School zones Orvis Risner Elementary School; Edmond, Oklahoma Vendor survey Construction zones Various Locations; Kansas, Nebraska, Iowa, and Missouri Vendor survey Highway-rail crossings Paramount Boulevard at Rosecrans Avenue; Paramount, California Vendor survey Interstate 95 at State Road 84; Fort Lauderdale, Florida Vendor survey I-126 at Greystone Boulevard; Columbia, South Carolina Transportation practitioner survey FM 127; Mount Pleasant, Texas Vendor survey US 59 at Loop 151 Flyover; Texarkana, Texas Vendor survey N200 between Overveen and Bloemendaa; Province of Noord- Holland, the Netherlands Vendor survey Horizontal curves A4226 (Five Mile Lane) Read the entire page →
From page 20... ... . Highway–Rail Crossings Paramount Boulevard at Rosecrans Avenue, Paramount, California The highway–rail crossing at the intersection of Paramount Boulevard and Rosecrans Avenue in Paramount, California, is atypical because the railroad crosses diagonally across the intersection and not just across one approach. Read the entire page →
From page 21... ... FIGURE 9 Horizontal curve IPM system application, Fort Lauderdale, Florida (Courtesy: Florida Department of Transportation) Read the entire page →
From page 22... ... I-126 at Greystone Boulevard, Columbia, South Carolina At the exit ramp to Greystone Boulevard from I-126 near Columbia, South Carolina, road users were observed traversing a horizontal curve with excess speed, leading to frequent run-off-the-road crashes into traffic control devices intended to warn the driver (e.g., chevron signing along the curve) Read the entire page →
From page 23... ... . FIGURE 14 Horizontal curve IPM system application, Texarkana, Texas (Courtesy: TxDOT Atlanta District) Read the entire page →
From page 24... ... . FIGURE 16 Horizontal curve IPM system application, Province of Noord-Holland, the Netherlands (Courtesy: Astucia Traffic Safety Systems) Read the entire page →
From page 25... ... Most recently, the Virginia Transportation Research Council (VTRC) has proposed using several different systems, including IPM systems with chase sequence capabilities to reflect variable speed limits, to help prevent crashes in fog-prone areas. Read the entire page →
From page 26... ... The forward chase sequence was perceived to be more effective in keeping traffic moving and, hence, is the only mode of operation used currently. Frequent LED failures, likely resulting from intersection traffic under normal operation and particularly from vibrations produced by heavy trucks, occur about once every two to three months. Read the entire page →
From page 27... ... This led to early cable fatigue and failure and subsequent whole system failures. Challenges also existed related to the design of the "merge" arrow as road users had difficulty determining 28 FIGURE 20 Merge location IPM system application, Wayne Township, New Jersey (Courtesy: HIL-Tech, Ltd.) Read the entire page →
From page 28... ... The IPM system cost was reported to be between $60,000 and $70,000; the length of the tunnel and the distance between markers was not reported. Caltrans personnel purport enhanced visibility for road users and a reduction in crashes as a result of the IPM system, but a formal evaluation has not been done to support these findings (G. Read the entire page →
From page 29... ... The average daily traffic for both directions of travel through the tunnel is 1,500 vehicles per day, and the posted speed limit is 45 mph. The IPM system markers are placed along the centerline for the length of the tunnel. Read the entire page →
From page 30... ... Ongoing annual costs associated with system maintenance are approximately $1,000. The operation and safety of the facility have improved with the addition of the IPM, WSDOT believes, although no formal evaluation is available (G. Read the entire page →
From page 31... ... Jefferson Street is a five-lane, one-way, eastbound street that intersects the METRORail line at Main Street. The motivation for this implementation was to increase road user awareness of the traffic FIGURE 29 Stop-bar application Amber Phase, Alabama Street at Galleria, Houston, Texas. Read the entire page →
From page 32... ... The short observation period and infrequent crash occurrence limits further conclusions related to the crash reduction potential of the IPM system at this site. These findings related to driver comprehension, traffic operations, and vehicle crashes at Jefferson Street are preliminary but promising. Read the entire page →
From page 33... ... . To supplement this dynamic lane control assignment system, Houston METRO in 2006 implemented an IPM system on the northbound and southbound approaches of Fannin Street at Dryden Street (see Figures 36 and 37) Read the entire page →
From page 34... ... The system is activated in a steady-burn state when the dynamic lane control assignment indicates a "Red X." The installation of the system involved cutting a groove in the pavement to place the inductive power loop, coring the pavement to install the power nodes, and adhering the markers to the pavement surface above the nodes. Not unique to this application, power supply issues were encountered early in IPM system operation but have since been resolved. Read the entire page →
From page 35... ... The driver comprehension study concluded that although most drivers understood that the purpose of the IPM system was to restrict access to the left-turn lane, some road users may be challenged to determine when a train is approaching or when they are allowed to enter the left-turn lane using the current dynamic lane control assignment and IPM system. The operational analysis for this combined dynamic lane control assignment and IPM system application considered five specific violation types: 1. Read the entire page →
From page 36... ... . N513 Highway, Castricum, Province of Noord-Holland, the Netherlands Along the N513 Highway in the Province of NoordHolland, the Netherlands, an IPM system was implemented as an alternative to overhead roadway lighting to address safety concerns in an environmentally sensitive location. Read the entire page →
From page 37... ... determine whether this result is notable (Astucia Traffic Safety Systems 2007a) Read the entire page →

From page 18...

... Table 3 lists novel IPM system applications, identified primarily through the transportation practitioner survey and the IPM system vendor survey. WARNING With the primary intent to warn road users, IPM systems have been implemented -- as an isolated system or in combination with other warning devices -- in school zones, in construction zones, at highway–rail crossings, along horizontal curves, and in areas that experience frequent adverse weather.