10,522 research outputs found
The Effect of Integrating Travel Time
This contribution demonstrates the potential gain for the quality of results
in a simulation of pedestrians when estimated remaining travel time is
considered as a determining factor for the movement of simulated pedestrians.
This is done twice: once for a force-based model and once for a cellular
automata-based model. The results show that for the (degree of realism of)
simulation results it is more relevant if estimated remaining travel time is
considered or not than which modeling technique is chosen -- here force-based
vs. cellular automata -- which normally is considered to be the most basic
choice of modeling approach.Comment: preprint of Pedestrian and Evacuation 2012 conference (PED2012)
contributio
Analyzing Stop-and-Go Waves by Experiment and Modeling
The main topic of this paper is the analysis and modeling of stop-and-go
waves, observable in experiments of single lane movement with pedestrians. The
velocity density relation using measurements on a 'microscopic' scale shows the
coexistence of two phases at one density. These data are used to calibrate and
verify a spatially continuous model. Several criteria are chosen that a model
has to satisfy: firstly we investigated the fundamental diagram (velocity
versus density) using different measurement methods. Furthermore the
trajectories are compared to the occurrence of stop-and-go waves qualitatively.
Finally we checked the distribution of the velocities at fixed density against
the experimental one. The adaptive velocity model introduced satisfies these
criteria well.Comment: Fifth International Conference on Pedestrian and Evacuation Dynamics,
March 8-10, 2010, National Institute of Standards and Technology,
Gaithersburg, MD US
Quantitative validation of PEDFLOW for description of unidirectional pedestrian dynamics
The results of a systematic quantitative validation of PEDFLOW based on the
experimental data from FZJ are presented. Unidirectional flow experiments,
totaling 28 different combinations with varying entry, corridor and exit
widths, were considered. The condition imposed on PEDFLOW was that all the
cases should be run with the same input parameters. The exit times and
fundamental diagrams for the measuring region were evaluated and compared. This
validation process led to modifications and enhancements of the model
underlying PEDFLOW. The preliminary conclusions indicate that the results agree
well for densities smaller than 3 m-2 and a good agreement is observed even at
high densities for the corridors with bcor = 2.4 m, and bcor = 3.0 m. For
densities between 1 and 2 m-2 the specific flow and velocities are
underpredicted by PEDFLOW.Comment: 6 pages, 3 figures, 1 Table, conference PED201
Steady State of Pedestrian Flow in Bottleneck Experiments
Experiments with pedestrians could depend strongly on initial conditions.
Comparisons of the results of such experiments require to distinguish carefully
between transient state and steady state. In this work, a feasible algorithm -
Cumulative Sum Control Chart - is proposed and improved to automatically detect
steady states from density and speed time series of bottleneck experiments. The
threshold of the detection parameter in the algorithm is calibrated using an
autoregressive model. Comparing the detected steady states with previous
manually selected ones, the modified algorithm gives more reproducible results.
For the applications, three groups of bottleneck experiments are analysed and
the steady states are detected. The study about pedestrian flow shows that the
difference between the flows in all states and in steady state mainly depends
on the ratio of pedestrian number to bottleneck width. When the ratio is higher
than a critical value (approximately 115 persons/m), the flow in all states is
almost identical with the flow in steady state. Thus we have more possibilities
to compare the flows from different experiments, especially when the detection
of steady states is difficult.Comment: 19 pages, 7 figure
Toward a Mathematical Theory of Behavioral-Social Dynamics for Pedestrian Crowds
This paper presents a new approach to behavioral-social dynamics of
pedestrian crowds by suitable development of methods of the kinetic theory. It
is shown how heterogeneous individual behaviors can modify the collective
dynamics, as well as how local unusual behaviors can propagate in the crowd.
The main feature of this approach is a detailed analysis of the interactions
between dynamics and social behaviors.Comment: 22 pages, 5 figure
Inflow process of pedestrians to a confined space
To better design safe and comfortable urban spaces, understanding the nature
of human crowd movement is important. However, precise interactions among
pedestrians are difficult to measure in the presence of their complex
decision-making processes and many related factors. While extensive studies on
pedestrian flow through bottlenecks and corridors have been conducted, the
dominant mode of interaction in these scenarios may not be relevant in
different scenarios. Here, we attempt to decipher the factors that affect human
reactions to other individuals from a different perspective. We conducted
experiments employing the inflow process in which pedestrians successively
enter a confined area (like an elevator) and look for a temporary position. In
this process, pedestrians have a wider range of options regarding their motion
than in the classical scenarios; therefore, other factors might become
relevant. The preference of location is visualized by pedestrian density
profiles obtained from recorded pedestrian trajectories. Non-trivial patterns
of space acquisition, e.g., an apparent preference for positions near corners,
were observed. This indicates the relevance of psychological and anticipative
factors beyond the private sphere, which have not been deeply discussed so far
in the literature on pedestrian dynamics. From the results, four major factors,
which we call flow avoidance, distance cost, angle cost, and boundary
preference, were suggested. We confirmed that a description of decision-making
based on these factors can give a rise to realistic preference patterns, using
a simple mathematical model. Our findings provide new perspectives and a
baseline for considering the optimization of design and safety in crowded
public areas and public transport carriers.Comment: 23 pages, 6 figure
Two dimensional outflows for cellular automata with shuffle updates
In this paper, we explore the two-dimensional behavior of cellular automata
with shuffle updates. As a test case, we consider the evacuation of a square
room by pedestrians modeled by a cellular automaton model with a static floor
field. Shuffle updates are characterized by a variable associated to each
particle and called phase, that can be interpreted as the phase in the step
cycle in the frame of pedestrian flows. Here we also introduce a dynamics for
these phases, in order to modify the properties of the model. We investigate in
particular the crossover between low- and high-density regimes that occurs when
the density of pedestrians increases, the dependency of the outflow in the
strength of the floor field, and the shape of the queue in front of the exit.
Eventually we discuss the relevance of these results for pedestrians.Comment: 20 pages, 5 figures. v2: 16 pages, 5 figures; changed the title,
abstract and structure of the paper. v3: minor change
Pedestrian, Crowd, and Evacuation Dynamics
This contribution describes efforts to model the behavior of individual
pedestrians and their interactions in crowds, which generate certain kinds of
self-organized patterns of motion. Moreover, this article focusses on the
dynamics of crowds in panic or evacuation situations, methods to optimize
building designs for egress, and factors potentially causing the breakdown of
orderly motion.Comment: This is a review paper. For related work see http://www.soms.ethz.c
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