Early Experience with Intra-Arterial Thrombolytic Therapy for Peripheral Arterial Occlusion

Reid, Donald B.; Reid, Alan; Cuschieri, R. J.; Lowe, G. D. O.; Pollock, Julius

doi:10.1177/003693309103600104

Cited by 4 publications

(6 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, some of the crossing conflict points are converted to safer diverging and merging conflict types. The reduction in conflict points and changes in conflict types are usually considered as indicators of reduced risk and severity of crashes (8,11,15,20). Driver behavior studies based on driving simulators or surveys have the potential to investigate driver perceptions and behavioral adaptations to AI designs, but no such studies have been conducted for QRIs to date.…”

Section: Traffic Safety Performancementioning

confidence: 99%

“…In practice, the most critical element of operating a QRI is to coordinate the main and secondary signals. For instance, at a single quadrant intersection, the main intersection operates as a simple two-phase signal, and the secondary intersections operate under a three-phase signal scheme with the through movement as the coordinated phase to the main intersection ( 8 ). Although the number of QRIs is limited, there is evidence showing the QRI is a promising design for the intersection of two high-volume multi-lane roadways.…”

Section: State-of-the-practicementioning

confidence: 99%

“…Therefore, instead of implementing protected left-turn phases, an alternative way is to redirect the leftturning traffic from the main intersection to sub-intersection(s) located downstream or upstream of the main intersection (4)(5)(6)(7). One such design is the quadrant roadway intersection (QRI), which includes a main intersection and secondary intersections that are linked by a connector road in one or more quadrants of the 1 intersection (8). Left-turn vehicles that would normally require a protected left-turn phase at the main intersection are instead rerouted via secondary intersections that can more easily handle the load.…”

mentioning

confidence: 99%

“…In the U.S., the concept of QRI design was first published in 2000, and the first QRI was opened in 2012 ( 8 ). To date, there are 11 QRIs of various types in operation in the U.S. ( 11 ).…”

mentioning

confidence: 99%

“…Some require out-of-direction travel, which may add travel time to left-turning traffic. There will also be additional delay introduced to through vehicles at the secondary intersections ( 8 ). Therefore, the operational analysis of QRIs should consider the entire system instead of merely focusing on the main intersection.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Quadrant Roadway Intersections: Tradeoffs between Control Delay Savings and Extra Travel Time

Yang,

Cunningham,

Brown

2023

Transportation Research Record: Journal of the Transportation R

View full text Add to dashboard Cite

A quadrant roadway intersection (QRI) reduces congestion relative to a four-phase intersection. (Note: this study relates to traffic systems where vehicles drive on the right-hand side of the road.) It does this by removing left-turn traffic from the main intersection, resulting in a two-phase signal. Nevertheless, there is a lack of clear understanding of the tradeoffs between savings in control delay versus extra travel time experienced by the rerouted movements. This research compared the operational performance of five QRI designs with the counterpart conventional intersection (CI) under various traffic demand scenarios via TransModeler microsimulation modeling. Three measures-of-effectiveness (MOEs) were employed: time-in-system (TIS), control delay, and intersection capacity utilization. Simulation results show that all QRI designs outperform CI design for all three MOEs under all demand scenarios. QRIs with direct left-turn design have a smaller average TIS than those with loop left-turn design, indicating that savings in control delays did not offset the extra travel times. Under a relatively low demand condition, a single QRI design can generally balance the tradeoffs between control delay and extra travel time. Under a high demand scenario, a dual or full QRI with direct left-turns is preferred, since it reroutes or partially reroutes left- and right-turn traffic to secondary intersections, thus the main intersection has a lower capacity utilization and can accommodate more through-traffic demands than CI, single QRI, and dual or full QRIs with loop left-turns.

show abstract

Section: Traffic Safety Performancementioning

confidence: 99%

Section: State-of-the-practicementioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations