Research in Progress (RIP) https://rip.trb.org/ en-us Copyright © 2026. National Academy of Sciences. All rights reserved. http://blogs.law.harvard.edu/tech/rss tris-trb@nas.edu (Bill McLeod) tris-trb@nas.edu (Bill McLeod) Research in Progress (RIP) https://rip.trb.org/Images/PageHeader-wTitle-RIP.jpg https://rip.trb.org/ Placement Options for In-street Pedestrian Crossing Signs (R1-6a) https://rip.trb.org/View/2593953 Thu, 28 Aug 2025 12:29:56 GMT https://rip.trb.org/View/2593953 Research and Assessment of Needs for Sign Maintenance https://rip.trb.org/View/2593930 Thu, 28 Aug 2025 11:32:30 GMT https://rip.trb.org/View/2593930 Size of Regulatory and Warning Signs https://rip.trb.org/View/2558385 Wed, 28 May 2025 14:05:40 GMT https://rip.trb.org/View/2558385 Compliance and Best Practices for Pavement Markings https://rip.trb.org/View/2244520 Thu, 14 Sep 2023 08:49:33 GMT https://rip.trb.org/View/2244520 Choosing Locations for Installation of Pedestrian Crossing Signs and Safety Measures at Non-signalized Intersections (Phase II) https://rip.trb.org/View/1881796 Mon, 04 Oct 2021 11:45:18 GMT https://rip.trb.org/View/1881796 SPR-4537: Speed Management on Freeways in Transition Zones between Rural and Urban Conditions https://rip.trb.org/View/1722748 Mon, 20 Jul 2020 12:51:00 GMT https://rip.trb.org/View/1722748 Support for AASHTO Committees and Councils. Support for Review of the Manual on Uniform Traffic Control Devices (MUTCD) Notice of Proposed Amendments (NPA) https://rip.trb.org/View/1671382 Tue, 10 Dec 2019 12:22:14 GMT https://rip.trb.org/View/1671382 SPR-4318: Installation and Maintenance of Raised Pavement Markers at State Transportation Agencies" Synthesis of Current Practices https://rip.trb.org/View/1603310 Thu, 02 May 2019 13:51:25 GMT https://rip.trb.org/View/1603310 Traffic Control Device (TCD) Consortium https://rip.trb.org/View/1492967 Fri, 22 Dec 2017 11:34:38 GMT https://rip.trb.org/View/1492967 Fostering Innovation in Pedestrian and Bicycle Transportation Pooled Fund Study https://rip.trb.org/View/1475618 Sun, 23 Jul 2017 14:46:36 GMT https://rip.trb.org/View/1475618 Impacts of Connected Vehicles and Automated Vehicles on State and Local Transportation Agencies--Task-Order Support. Impacts of Connected and Automated Vehicle Technologies on the Highway Infrastructure https://rip.trb.org/View/1467505 Fri, 19 May 2017 10:17:51 GMT https://rip.trb.org/View/1467505 Guide for Roundabouts https://rip.trb.org/View/1466747 Fri, 12 May 2017 10:44:10 GMT https://rip.trb.org/View/1466747 Assessing the Safety Issues Associated with Isolated Rural Intersections https://rip.trb.org/View/1455578 Fri, 17 Feb 2017 14:45:32 GMT https://rip.trb.org/View/1455578 Warrant Development for Signalization of Superstreet Intersections with Two or Three Approaches https://rip.trb.org/View/1423761 Mon, 19 Sep 2016 16:26:24 GMT https://rip.trb.org/View/1423761 Driving Simulator Study of Merge Signs https://rip.trb.org/View/1372824 Tue, 27 Oct 2015 11:29:01 GMT https://rip.trb.org/View/1372824