Question

Provide definitions for each of the folowing dont copy paste from google

concurrency group

movement

NEMA phase numbering

overlap

phase

ring

ring barrier diagram

Answer 1

The ring barrier diagram-

The ring barrier diagram specifies the safe sequencing of phases (and thus the movements that they control) at a signalized intersection.

Movement and Phase-

The movement and the phase are often used interchangeably,but are distinct and mean different things.Firstly the term movement can be defined as the response of the user to a "go" indication. This response has two attributes: The courier direction from which the user originates and the turn which the user makes. The
compass direction normally includes one of the following designations: eastbound, westbound, northbound,
or southbound. The turn designation includes left turn, through, or right turn.
We can also say whether a movement is opposed or not by another movement by using the terms protected,
permitted, or not opposed. A protected movement has the unambiguous right-of-way, while a permitted
movement may continue through the intersection only when there is a large enough (and safe) gap in the
opposing traffi c movement.
Left turn movements are designated with odd
numbers (1, 3, 5, and 7) and through movements are designated as even numbers (2, 4, 6, and 8). While right
turn movements are often given the same number as their compatible through movements, they are sometimes
given the same right digit with a leading “1.”
A phase is a timing unit that controls one or more movements. The timing unit includes three timing intervals,
one each for the indications of green, yellow, and red. Phases are typically numbered in the same way as
movements, with the exception that the even numbered phases normally control both the through and right-turn
movements. standard NEMA phasing convention (so-named since the National Electrical
Manufacturers Association has established standards for the operation of an actuated traffi c controller). For
consistency, phases 2 and 6 should correspond to the through movements on the major street, while phases
4 and 8 should correspond to the through movements on the minor street.