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Detailed Intersection Control Information (ICI); including timing; phasing; geometric; and demand attributes; is an increasingly important resource for researchers; consultants; and private sector companies for many applications; including development of traffic models and technologies such as vehicle information or automation systems. While this information has historically been difficult to distribute due to variations in the availability and format across the numerous jurisdictions that operate signals; recent trends toward increased use of Central Traffic Signal Control Systems (CTSCSs) have made creation of a unified; standardized system for organizing ICI more feasible. To help work toward this; in this project researchers interviewed and surveyed signal operation engineers and transportation modelers throughout Minnesota to learn how different jurisdictions manage information relating to their signals and how this information is used for operations and planning. With this information; researchers developed a comprehensive Unified Set of Intersection Control Information (U-ICI) that contains all the information required to describe the control of an intersection in a format that is readable by both humans and machines. Along with this; researchers evaluated the availability of this information and the feasibility of using existing CTSCS applications to store this information. While the researchers conclude that it is not feasible to use these applications to store all of the U-ICI; the applications will likely make the process of implementing and populating such a system easier. Though some information may be contained in formats that will require manual effort to digitize; the up-front effort to do so will be a worthwhile pursuit.

The Smart Work Zone Speed Notification (SWZSN) system aims to alleviate congestion; queuing; and rear end crashes in work zones by informing drivers of the speed of the downstream segment using a type of portable Intelligent Lane Control System (ILCS); Portable Changeable Message Signs (PCMS). The hypothesis was that drivers; knowing the speed up to 1 mile downstream; will slow down early or at least be alert and perform smoother decelerations. Video of the SWZSN was analyzed over two years of operation by the Minnesota Traffic Observatory. Overall; the system resulted in beneficial reductions of selected decelerations by the drivers. In situations where the messages communicated to the drivers were consistent and accurate; reductions of more than 30% in the selected deceleration rates were observed. Unfortunately; there were several cases where counterproductive or misleading messages were communicated to the drivers; prompting relative increases to the selected deceleration rates. The most important observation; stemming from both positive and negative influences; was that the speed notification system was noticed by drivers and resulted in a statistically significant influence on driving behavior; unlike other driver alert systems.

Pedestrian-Activated Crossing (PAC) systems have been shown to have a generally positive impact on driver yield rates. However; there has been insufficient research on the effect PAC treatments have on pedestrian crash rates; and there is little guidance as to when and where each treatment should be used. This study estimates the effects of PACs on pedestrian crash rates using Monte Carlo simulation and examines the relationships between driver yield rates and a variety of treatments and site designs by conducting an observational study using video data from 34 locations. The simulation outcomes suggests that while the percentage of yielding drivers might be a useful indicator of pedestrian level of service; it is less helpful as safety surrogate. This could be because a driver's yielding to a pedestrian; as observed in field studies; might not be the same behavior as a driver attempting to stop during a vehicle/pedestrian conflict. The observational study shows that the number of lanes to cross at a crossing is positively correlated with the rate at which pedestrians activate the system; but it is not correlated with the delay. Additionally; the study showed that the effect of PAC systems is most pronounced at sites with a higher number of movements conflicting with the crossing or poor visibility from upstream without signs warning drivers of an upcoming crosswalk.

Appendix E (FULL EXAMPLE OF ICI FROM DIVERGING DIAMOND INTERCHANGE AT HENNEPIN COUNTY ROAD 144 AND TH-101 IN ROGERS, MN) was published separately from report 2019-14, Evaluation of a Central Traffic Signal System and Best Practices for Implementation.