Simulation of information flow on dynamic interlinked networks.

1. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Simulation of dynamical information
spread during pedestrian evacuation
M. Kämpf, C. Napierala, J.W. Kantelhardt
DPG Frühjahrstagung 2012 - 29. März - Berlin
Martin-Luther Universität Halle-Wittenberg
Institut für Physik
FG für Theoretische Physik
SOE 18.1

2. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Measurement of Crowd Properties :
London - Lord Mayors Show 2011
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

3. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Introduction :
• We study crowd dynamics
and information flow during
evacuation processes.
• We are focused on the flow
of information and on
quality of information in a
system without any
centralized communication
and control infrastructure.
• We want to meassure, what
can be known inside such a
self organized system at any
time and place and how this
knowledge can be distributed
efficently.
Lord Mayor Show
London - 2011
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

4. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Extended Properties
Dynamic Lattice Structure
Social Network
Communication Network
• all elements have the
same properties
• only simple interactions
• no interaction with the
area, accept of walls
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

5. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
A Complex System ?
• Such a system consists of fairly simple components.
• We can not analyze the properties of
agent-structure-information-interactions
by decoupling these aspects.
• As it is a Complex System - we are looking
for emerging properties / phenomena which
are not obviously visible by looking
on isolated parts.
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

6. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Our approach :
A lattice gas model is combined with
an agent based simulation
• simple geometry, extendable to real
world like structures
• agents movement is limited to 6
directions in space and to one
movement per time step
• agents move according to simple rules
based on properties of the area and
their knowledge
• information flow is modeled as an
additional layer on top of the agents'
movement based on epidemic models
Density: 3%, 9%,
30% 95%
restricted
area
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

7. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Context of our Research :
• Real world data sets for comparison of results
–Evacuation exercise at University Krakow
–Note Bianca in Malta
–Lord Mayor's Show London
• Comparison with epidemic models
–SIR and SIS model
• Numerical Simulations in a discrete space
–compared with results from continous space model
• Construction of interconnected networks
–Building structure, and ad-hoc connected agents
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

8. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
S = susceptible, I = infectious, R= Recovered
• Valid for a large numbers of individuals
• Nonlinear system
• No generic analytical solution
Epidemic Models : SIR & SIS Model
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

9. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Meassurement of Infection Ratio
InfectionRatio
InfectionRate
We count the number of infected
(or: informed) agents
For an intermediate fit interval
the average slope is determined
numericaly

10. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
First results : Rate of Infection (low density)
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

11. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
First results : Rate of Infection (high density)
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

12. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Conclusion:
• Information flow has a strong dependence
on the density of agents with communi-
cation devices, but hardly depends on the
structure of the building.
• Different communication strategies
influence the information flow more
than a restricted geometry.
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

13. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Quality of Information :
View of an agent :
How does the quality of
information available
to an agent evolve in time?
General view :
What amount of truth can be
known at a certain point in
space and time?
What parameters affect this
information?
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

14. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Outlook: Interconnected Networks
From "Lattice Gas Model" to a Network
–collective properties of all places in
a stairway define the edge properties
–possible flow on a crossing point
defines node properties
Combined Networks
–lane-network and communication network are inter connected
by the agents which are walking within the lane network but
rely on the information transmitted through the
communication network.
SOE 18.1 - Simulation of dynamical information spread during pedestrian evacuation

15. Martin-Luther Universität Halle-Wittenberg · Institut für Physik · FG Theoretische Physik
Mirko Kämpf
Martin Luther Universität Halle-Wittenberg
Naturwissenschaftliche Fakultät II
Institut für Physik
Von-Seckendorff-Platz 1
06120 Halle
Germany
phone: (+49) 345 55 25447
fax: (+49) 345 55 25446
e-mail: mirko.kaempf@physik.uni-halle.de