What is a series of conflicting phases that occur in an established order, but can never occur simultaneously with each other?

The concept of a series of conflicting phases that occur in an established order but can never occur simultaneously is best represented by the term "traffic signal controller ring." In traffic signal operations, a controller ring is a designated sequence of signal phases that are programmed to manage traffic flow safely and efficiently at an intersection. Each phase is designed to control a specific movement of traffic, and conflicting phases, such as those that would allow vehicles to move in opposite directions at the same time, are carefully arranged so they cannot happen simultaneously. This ensures safety and prevents accidents at intersections.

In considering the other options, while a sequence of operation refers to the programmed actions of the traffic signal, it doesn't specifically emphasize the conflict aspect of phases. A traffic flow pattern describes how vehicles and pedestrians move through an intersection but does not imply a predefined conflicting sequence. The cycle of phases could refer to the entire set of phases in a complete signal cycle, but it does not address the aspect of established order and conflict specifically as the traffic signal controller ring does.