Doyoon expanded the search range by one level. He extended the time window by an hour and added two additional residential sectors to the radius. The filter remained simple. Density formation. Directional adjustment. Rapid narrowing of spacing. Conversion into accident was not included as a condition. Only the structure remained.
The results aligned quickly.
Two near the transfer corridor. Three at different intersections. One at a bus stop. One inside a hospital lobby. None had converted into minor contact incidents. All had formed compression near threshold before dispersing.
He continued scrolling.
He verified the filter again. Same structural type. Same time range. Same living radius. No error.
The count was higher than expected.
He opened one case. Intersection radius. Late afternoon. Vehicle rotation intersecting pedestrian flow. Spacing recovered before collapse. No accident.
Another case. Hospital entrance corridor. Visiting hours ending. Density formed. Directional shift overlapped. Convergence dissolved. No accident.
Doyoon lifted his wrist. The second hand moved steadily. He did not check the exact time. He only sensed the familiar few minutes of displacement.
He minimized the screen. Dots marked the map. Different locations. Identical sequence. Density. Adjustment. Near-collapse.
He expanded the time range once more.
The number of dots increased.
This was not a handful of cases.
Doyoon stood without closing the screen. The expanded dataset remained visible behind him. The marked points did not shrink.
Outside the building, pedestrian flow entered his field of view immediately. The lunch hour had passed, yet density held steady. People gathered at crosswalks. A line formed at the bus stop. Two individuals paused near a convenience store entrance.
The compression was not severe. But directional shifts were frequent. One person slowed, spacing tightened. Another stepped aside, alignment distorted.
Not threshold. Not yet.
He avoided focusing on one point for too long. While his gaze lingered, another structure began forming elsewhere. On the right side of the intersection, strides misaligned. At the same time, the bus stop line narrowed sharply.
He shifted his attention.
Intervening in one place meant leaving another unattended.
He could step toward the intersection center. He could widen spacing at the bus stop entrance. The two structures were separate in space, but they overlapped in time.
He paused.
The expanded range was no longer confined to the screen. It had widened in the street.
The second hand moved once more in his mind. He did not look at his wrist.
Compression was forming simultaneously.
The traffic signal was about to change. In the right lane, a vehicle slowed to turn left into the intersection. Pedestrians leaned forward as the light shifted. At the bus stop, a vehicle arrived and the waiting line compressed abruptly. The two structures were separate, but the moment overlapped.
Doyoon calculated the intersection first. Turning radius. Pedestrian stride. Remaining signal time. Close to threshold. One overlapping directional shift could collapse the spacing near the center line.
He stepped forward.
Not to the center, but to the edge of the flow. He adjusted his position slightly. The pedestrian behind him slowed. The stride ahead lengthened. The vehicle respected the stop line. Convergence did not form.
At that moment, a short sound came from the left.
The bus stop.
Spacing narrowed too quickly. One person was pushed backward. A foot slipped. Balance faltered. The fall was minor, but contact occurred. Two bystanders reached out at the same time. The structure dispersed, but too late to prevent impact.
Doyoon turned his head.
It was already over.
The intersection remained stable. The bus stop returned to order. The contact would likely be recorded.
He understood that he could not calculate both simultaneously. The moment the range expanded, the choice multiplied.
He did not check his watch.
He prevented one.
The other was recorded.