Traffic flow behavior at un-signalized intersection with crossings pedestrians

Mixed traffic flux composed of crossing pedestrians and vehicles extensively exists in cities. To study the characteristics of the interference traffic flux, we develop a pedestrian-vehicle cellular automata model to present the interaction behaviors on a simple cross road. By realizing the fundamental parameters (i.e. injecting rates ${\alpha }_1$, ${\alpha }_2$, the extracting rate β and the pedestrian arrival rate ${\alpha }_P$), simulations are carried out. The vehicular traffic flux is calculated in terms of rates. The effect of the crosswalk can be regarded as a dynamic impurity. The system phase diagrams in the $({\alpha }_1,{\alpha }_P)$ plane are built. It is found that the phase diagrams consist essentially of four phases namely Free Flow, Congested, Maximal Current and Gridlock. The value of the Maximal current phase depends on the extracting rate β, while the Gridlock phase is achieved only when the pedestrians generating rate is higher than a critical value. Furthermore, the effect of vehicles changing lane ($P_{\mathrm{ch}1},P_{\mathrm{ch}2}$) and the location of the crosswalk $X_P$ on the dynamic characteristics of vehicles flow are investigated. It is found that traffic situation in the system is slightly enhanced if the location of the crosswalks $X_P$ is far from the intersection. However, when $P_{\mathrm{ch}1}$, $P_{\mathrm{ch}2}$ increase, the traffic becomes congested and the Gridlock phase enlarges.     

Analysis of repulsion states among pedestrians inflowing into a room

One of the characteristics of inflow processes within a room is the changing spatial configuration of people that are in the room due to the entering of new pedestrians. Each entry produces a break of the spatial configuration. Such break can be effectively represented by the proxemics, which describes the repulsion among pedestrians. In this study, we deeply investigate the properties of proxemics defined for pedestrians, who inflow within a room. We analyzed two different cases: when some of the pedestrians are inactive and when no inactive people are present. In both cases the proxemics is characterized by a succession of upward step-like variations superimposed to an initial increasing behavior that tends to stabilize through time. The derivative of the proxemics, which indicates increase of repulsion (if positive) and decrease of repulsion (if negative) among pedestrians, is persistent; however, in case of absence of inactive persons, it increases with the number of moving people, while it remains almost constant when inactive persons obstruct the free movement of the other pedestrians.     

Dynamics of pedestrians in regions with no visibility— A lattice model without exclusion

We investigate the motion of pedestrians through obscure corridors where the lack of visibility (due to smoke, fog, darkness, etc.) hides the precise position of the exits. We focus our attention on a set of basic mechanisms, which we assume to be governing the dynamics at the individual level. Using a lattice model, we explore the effects of non-exclusion on the overall exit flux (evacuation rate). More precisely, we study the effect of the buddying threshold (of no-exclusion per site) on the dynamics of the crowd and investigate to which extent our model confirms the following pattern revealed by investigations on real emergencies: If the evacuees tend to cooperate and act altruistically, then their collective action tends to favor the occurrence of disasters. The research reported here opens many fundamental questions and should be seen therefore as a preliminary investigation of the very complex behavior of the people and their motion in dark regions.