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Browsing by Author "Schreiner, Christopher S."

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    Improvement of Conspicuity of Trailblazing Signs: Phase III-Evaluation of Fluorescent Colors
    Neale, Vicki L.; Anders, Richard L.; Schreiner, Christopher S.; Brich, Stephen C. (Virginia Center for Transportation Innovation and Research, 2001-02)
    This report represents a Phase III effort to design and evaluate a new sign design for incident route trailblazing. The colors evaluated were fluorescent coral, fluorescent purple, fluorescent yellow-green, and non-fluorescent purple. The results indicate no significant differences in driving performance with regard to the four experimental sign color combinations. Regarding the subjective preference questionnaires, significant questionnaire results along with trend information suggest that black on fluorescent yellow green was the most preferred by younger and older drivers during both day and night visibility conditions. Nonetheless, this sign color has been assigned by FHWA for pedestrian, school, and bicycle crossings, which eliminated the opportunity to use fluorescent yellow-green as a unique sign color for trailblazing in incident management situations. Preference for non-fluorescent yellow on purple consistently increased at night when the sign became more luminant; however, the overall preference for this sign color combination was lower than for the other sign color combinations tested in this study. With the elimination of these two signs, the remaining contenders for a unique sign color combination were black on fluorescent coral and fluorescent yellow on fluorescent purple. Black on fluorescent coral was ranked significantly higher than fluorescent yellow on fluorescent purple for visibility and for overall preference. Questionnaire trend information suggests that black on fluorescent coral was more preferred than fluorescent yellow on fluorescent purple during daytime viewing conditions and less preferred than fluorescent yellow on fluorescent purple during nighttime viewing conditions. The overlay film used for the fluorescent coral sign was a first generation material that can reasonably be expected to result in improved nighttime luminance when produced in a full production run. In addition to the study results, drivers commented that the arrow on the sign was too small to determine directional information from a comfortable distance. Based on such driver comments, the research conclusions, and the federal regulations enacted since the outset of this series of experiments, the following recommendations are made: (1) black on fluorescent coral should be used as a unique incident management sign color, and (2) the directional arrow on the sign should be larger.
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    Reducing fog-related crashes on the Afton and Fancy Gap Mountain sections of I-64 and I-77 in Virginia
    Lynn, Cheryl; Schreiner, Christopher S.; Campbell, Ross (Virginia Center for Transportation Innovation and Research, 2002-10)
    The Fancy Gap and Afton Mountain interstates have a long history of fog-related, multivehicle crashes. Because of its earlier involvement in the installation and evaluation of the original Afton Mountain in-pavement fog guide light system, and concerns about continuing fog crash problems, the Virginia Transportation Research Council (VTRC) created an expert panel made up of decision makers from the Virginia Department of Transportation (VDOT) and the Virginia Department of State Police (VSP). Personnel from the Virginia Tech Transportation Institute and VTRC staffed the panel. After detailed crash analyses, a review of the literature on fog and its effects, and an extensive survey of fog mitigation systems in the United States and abroad, the panel issued the following recommendations: (1) Install variable message signs (VMSs) immediately prior to the most fog-prone areas to warn drivers of detected incidents, fog-related vehicle stops, or slowdowns ahead. Use highway advisory radio within the fog zone to communicate with drivers. (2) Install video cameras on the Afton and Fancy Gap fog areas to allow police and VDOT officials to confirm the presence of high-density fog areas and to allow the public to better plan their travel routes. Explore the use of ultra-low temperature, infrared video cameras to penetrate fog. (3) Increase police visibility in the fog areas to improve compliance with posted speed limits and advisory limits, including increased patrols and possible staff assignments to I-77 at Fancy Gap and I-64 at Afton. (4) Seek authorization for experimental use of advisory and regulatory variable speed limits on I-77 as part of the new Fancy Gap fog mitigation system. (5) Conduct research to improve the legibility and visibility of VMSs in fog. Also, study the effectiveness of static signs augmented with strobes and lasers to warn drivers of detected incidents and slowdowns in the fog zone. Because the panel represented multiple levels of VDOT and VSP and had extensive experience with the fog problems under consideration, a wide variety of solutions were offered for consideration, and each was judged from a variety of perspectives. The result was that only practical, applicable, and highly effective solutions were chosen for implementation. Because the group had representatives with extensive technical expertise in intelligent transportation systems (ITS) to advise them, they had confidence that their recommendations would be both workable and effective. It may be that this method of building consensus and support can be used as a model to promote deployment of ITS technologies to serve site-specific safety problems.