Entropy and Dynamics Analysis of Crowd Motions Phase Transition

In the crowd security research area a primary concern is to identify and control the transitions of the crowd motions. The order parameter and the entropy as a measure of order and disorder respectively, are essential parameters in this research area. This paper introduces a newly-developed crowd behavior entropy model to characterize the crowd motions and to research the sudden transition of the crowd based on the social entropy theory. Velocity direction and magnitude are both included. To simulate the crowd motions, experiments have been done using social force model. Results revealed the relation between the social entropy, order parameter, and the mass status. This paper established a baseline for crowd motion evaluation by incorporating the social entropy theory with the order parameter measurement. The work broadened the crowd motion management study by inducting artificial attractive force into the crowd, creating the statistical model and developing the order evaluation criteria. Keywords—Crowd motions, crowd behavior entropy, order parameter, phase transition

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