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From page 158... ... This appendix provides further description of the strategies and treatments in Categories 2 through 5: information collection and dissemination, vehicle technologies, incident and special event management, and infrastructure improvements and demand optimization. Finally, it provides examples of treatments and impacts designed to increase travel time savings in these categories. Read the entire page →
From page 159... ... 159 the detection range of the reader, the tag communicates information about the vehicle's speed, position, and direction to the roadway central office through a dedicated data link such as a wireless network. A radio frequency identification (RFID) Read the entire page →
From page 160... ... 160 increase mobility, improve productivity, and protect the environment. Adverse weather conditions pose a significant threat to the operation of the nation's roads. Read the entire page →
From page 161... ... 161 • Vision enhancement systems (night or fog assistance) ; • Rollover and stability control; • Traction control; • Lane-departure warning; and • Work zone, pedestrian-crossing, and rail–highway intersection warnings. Read the entire page →
From page 162... ... 162 Examples of work zone management applications in the United States include Colorado DOT's traffic incident management program for several long-term construction projects (the T-REX project in Denver and the COSMIX project in Colorado Springs) , and North Carolina DOT's real-time work zone information system on I-95 north of Fayetteville in 2002 (Dowling 2009) Read the entire page →
From page 163... ... 163 lanes on a roadway in determining the capacity and performance of an urban roadway. traNsPortatioN maNagemeNt ceNters Transportation management centers (TMCs) Read the entire page →
From page 164... ... 164 detection of traffic, downstream signal arrival prediction, and adjustment of the downstream signal operation on the basis of that prediction. Traffic adaptive signal control systems coordinate the control of traffic signals along arterial corridors and adjust the signal phase lengths according to prevailing traffic conditions. Read the entire page →
From page 165... ... 165 freeway ramp metering have shown very little to no diversion of demand to downstream freeway ramp sections. In Honolulu, Hawaii, as an experiment, the Lunalilo Street entrance ramp on the H-1 freeway was closed during the a.m. Read the entire page →
From page 166... ... 166 reasons. Electronic toll collection may use toll tag readers, license plate recognition, cell phones, or GPS units. Read the entire page →
From page 167... ... 167 Multimodal Travel Integrated multimodal corridors. Integrated multimodal corridors allow various partner agencies to manage the transportation corridor as a system rather than relying on the traditional approach of managing individual assets. Read the entire page →
From page 168... ... 168 Table F.1. Key Quantitative Benefits for Operational Strategies Category and Strategy Treatment Key Quantitative Benefit Information collection and dissemination Surveillance and detection Remote verification (closed-circuit television) Read the entire page →
From page 169... ... 169 Automated Enforcement: Speed, Red-Light, Toll, HOV • Safety 44 The installation of speed enforcement cameras in the United Kingdom led to a decrease in casualties by an average of 28% (Hess and Polak 2004) Read the entire page →
From page 170... ... 170 and 2002 indicated that the installation of a speed limit enforcement camera can be expected to lead to decreases in injury accidents by 45% (Hess and Polak 2004) Read the entire page →
From page 171... ... 171 • Customer satisfaction: Fifteen months after extensive deployment of automated speed enforcement cameras in the United Kingdom, a nationwide survey found that 70% of those surveyed thought that well-placed cameras were a useful way of reducing crashes and saving lives, while 21% thought that speed cameras were an infringement of civil liberties. Public opinion surveys indicated 60% to 80% support for red-light enforcement camera programs (Lee and Chow 2009) Read the entire page →
From page 172... ... 172 when compared to nonusers. The combination of 511 and DMSs showed that the reductions can be up to 24% (Transportation Research Record: Journal of the Transportation Research Board, No. Read the entire page →
From page 173... ... 173 44 Winter maintenance personnel from several agencies indicated that use of RWIS decreases salt use and antiicing techniques and limits damage to roadside vegetation, groundwater, and air quality (in areas where abrasives are applied) (Maccubbin et al. Read the entire page →
From page 174... ... 174 Roadside Messages: Treatments and Impacts Travel Time Message Signs for Travelers, Queue-Warning Systems • Safety 44 San Antonio, Texas, experienced a reduction of 2.8% in crashes (ITS Joint Program Office, U.S. Department of Transportation 2009) Read the entire page →
From page 175... ... 175 • Safety 44 A field evaluation in Michigan tested advanced cruise control (ACC) combined with forward-collision warning to form an automotive collision avoidance system (ACAS) Read the entire page →
From page 176... ... 176 program would save approximately 33 vehicle hours in travel delay per incident (Chou and Miller-Hooks 2009) Read the entire page →
From page 177... ... 177 44 A simulation study in Seattle showed that an incident management system with a traffic information system provided a fuel economy improvement of 1.3% (ITS Joint Program Office, U.S. Department of Transportation 2009) Read the entire page →
From page 178... ... 178 travel time by 4,671 passenger-hours (37%) (Freeway Bottleneck Study 2009) Read the entire page →
From page 179... ... 179 44 The Wisconsin DOT's freeway traffic management system resulted in a decrease in crashes of 14.8% (RITA, U.S. Department of Transportation 2013) Read the entire page →
From page 180... ... 180 Traffic-Signal Preemption at Grade Crossings • Safety 44 Automated enforcement systems have reduced highway–rail crossing violations by 78% to 92% along two corridors in Los Angeles, California (RITA, U.S. Department of Transportation 2013) Read the entire page →
From page 181... ... 181 • Mobility 44 In Toronto, Ontario, Canada, transit signal priority reduced transit delay by 30% to 40% and travel time by 2% to 6% (ITS Joint Program Office, U.S. Department of Transportation 2009) Read the entire page →
From page 182... ... 182 freeways was deactivated (RITA, U.S. Department of Transportation 2013) Read the entire page →
From page 183... ... 183 that critical occupancy is shifted to higher levels, which enabled higher flows (Transportation Research Record: Journal of the Transportation Research Board, No. Read the entire page →
From page 184... ... 184 Cordon Pricing (Areawide) • Mobility 44 During the first few months of the congestion charging program in London, automobile traffic declined by about 20% in the charge zone (a reduction of about 20,000 vehicles per day) Read the entire page →
From page 185... ... 185 turnover, reduce space requirements, and decrease sicktime use by 2 days, resulting in a total savings per employee of an estimated $12,000 annually (Telecommuting/ Telework Programs 2001) Read the entire page →

From page 158...

... This appendix provides further description of the strategies and treatments in Categories 2 through 5: information collection and dissemination, vehicle technologies, incident and special event management, and infrastructure improvements and demand optimization. Finally, it provides examples of treatments and impacts designed to increase travel time savings in these categories.