From the Lighting Research Center (LRC) press release:

Roundabouts, also known as traffic circles, are increasing in number across the U.S. These intersections generally increase traffic throughput while reducing the severity of automobile accidents. However, as relatively new traffic features, modern roundabouts are sometimes described as confusing for drivers. One difference between roundabouts and conventional cross-type intersections is the location of pedestrian crosswalks. Drivers may be less familiar with the location of crosswalks when driving through a roundabout.

The Lighting Research Center at Rensselaer Polytechnic Institute has developed a concept for roadway illumination called “Ecoluminance” which incorporates roadside vegetation with low-level pedestrian and landscape lighting, retroreflective markers, and light-emitting diode (LED) road and walkway illumination.

Click here for the published research paper