Flow direction: Unknown

Boundary conditions: Open

Places of research: Russia/USSR

Underlying data: Field inquiries and experimental research

Data collection: Two different methods

1st method: Observation on location

• To simultaneously gather data of the concentration and velocity a section of a footpath was determined (see graphic below).
• An observer stood at the end of the section.
• After the observer had marked a person in the crowd, he registered his arrival at the beginning of the section.
• At this moment he began the time measurement and started to count the people passing him.
• When the marked person arrived at his position the observer stopped the time measurement and the count.
• As a result one got the number of people in a measured area, hence the medial concentration, and the time of movement through a measured area, hence the medial velocity.

2nd method: Observation of photographs

• A characteristic section of a footpath was photographed from an elavated position and the measurements of the section were recorded.
• The photographs were taken in regular intervals (3...5 s).
• On the series of photographs a marked person was observed.
• By counting the people in the measured area the medial concentration was obtained for each photograph and for the course of time of a marked person passing the section.
• By observing the location of a marked person and the time he needed for passing the section the medial velocity was obtained.