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DTRT07-G-0003, Actuated traffic signal controls at isolated intersections largely benefit from gap-out and phase skip features as they allow, unused green times to be re-allocated to those movements need them. A few studies indicated that lane-by-lane gap-out, should be implemented for multi-lane approaches instead of traditional combined single channel gap-out. While the lane-bylane, gap-out is logically better than the combined channel gap-out, no studies have shown the delay benefits under the, optimized green splits and gap-out times., This research developed a lane-by-lane gap-out-based actuated signal control optimization method and evaluated its, performance using four demand cases covering volume-to-capacity ratios between 0.4 and 1.3. A simulation-based study, indicated that the lane-by-lane gap-out outperformed the combined single channel gap-out for all these cases. It was found, that over 12% total delay savings were observed for high volume-to-capacity ratio cases.

USDOT-TPSU-UV-0003-1113, Through the last half of the 19th century and most of the 20th century, increases in transportation productivity came directly from massive capital investment in the modal systems. With the completion of the Interstate highway system the focus has changed. Fiscal constraints preclude system expansion at the pace needed to support continued robust economic growth. Therefore, attention in the public sector has shifted to getting more productivity out og the existing modal infrastructure through improvements in system operation and management. This shift from capital construction to asset management is also motivated by increased emphasis at all governmental levels on minimizing the adverse environmental and societal effects of transportation activities.