Collective Dynamics (E-Journal)
Not a member yet
185 research outputs found
Sort by
Estimating Pedestrian Flows Using Route Distributions and Sparse Counting Data
Full text linkAt metro station Münchner Freiheit in Munich soccer fans cause congestion before and after soccer matches on the shortest route to get from a bus station to the metro. Yet, an online survey suggests that, given the right information and incentive through a mobile app, fans are willing to take a detour. In this study we combine the survey results with passenger counts collected in a field study to quantitatively estimate the number of rerouted pedestrians in dependency of influx from a side entrance for which there is no data. We find a realistic range for the change in flow, despite incomplete measurement data, that we use as input for predictive simulations. The quantitative results are also helpful for traffic management
What Can Be Learned From (Public) Running Result Data?
Full text linkResults from running races is available in abundance. In this contribution it is shown, how this data might help to understand pedestrian dynamics in general, as well as the situation at the start and experience for runners
The Evaluation of Data Fitting Approaches for Speed/Flow Density Relationships
Full text linkThis paper presents guidance on data-fitting approaches in the context of pedestrian and evacuation dynamics research. In particular, it examines parametric and non-parametric regression techniques for analysing speed/flow density relationships. Parametric models assume predefined functional forms, while non-parametric models provide flexibility to capture complex relationships. This paper evaluates a range of traditional statistical approaches and machine-learning techniques. It emphasises the importance of weighting unbalanced datasets to enhance model accuracy. Practical applications are illustrated using traffic and pedestrian evacuation data.
This paper is intended to stimulate discussion on best practices for developing, calibrating, and testing macroscopic and microscopic evacuation models. It does not prescribe a one-size-fits-all solution for evacuation data fitting approaches, but it provides an overview of existing methods and analyses their advantages and limitations
DIN 18009-2 – a New German Standard on Evacuation Simulation
Full text linkAfter more than eight years of intensive work, the second part of the German DIN 18009 standard on "Simulation of evacuation and personal safety" was published in August 2022. The DIN 18009 series offers a guideline for fire protection engineering for Germany. The first part "Principles and application rules" was published in 2016, with further parts describing standards for smoke simulation and safety concepts to follow. This marks a milestone in the application of simulation models in the safety context for Germany. This article discusses the advantages and disadvantages of prescriptive guidelines and performance-based engineering methods in the context of building evacuation. Furthermore, aspects of the application of the DIN 18009-2 are highlighted, and what challenges are still to be tackled and how. This includes in particular the choice and definition of scenarios and performance criteria
Be FAIR to Pedestrian Dynamics Data
Full text linkFor improving the safety of people in large crowds, it is of great importance to understand the basic mechanisms of pedestrian dynamics, e.g. with help of experiments. The number of openly shared datasets of these experiments has increased in the last years also due to stricter requirements from journals and funders. We share our own experimental data by an open access data archive which data is widely used in the community.
However, our data and also data of other researchers in the field of pedestrian dynamics is not annotated in a systematic or semantically harmonized way, which impairs FAIRness in general and interoperability specifically. In this paper, we propose a standardized extensible metadata schema and key data structures for trajectories and geometry. The proposed metadata schema and data structures hopefully support the interoperability within the community and will assist to make data reutilization more efficient.
Our own legacy datasets are continuously annotated with essential information using this metadata schema steadily. This metadata is provided beside the converted data on our data archive and thus enhance its findability and reusability
Simulation of Downhill Skiing Areas
Full text linkBased on video analysis of downhill skiing areas a model for ski traffic is developed. The video analysis uses PeTrack to determine the trajectories of individual skiers which are then statistically analysed. A stochastic cellular automaton model is proposed that can reproduce the basic observed features. The empirical data are used for validation and calibration of the model. In the future, the model may help to analyse comfort and safety on skiing slopes, especially the risk of collisions
A Rumor has Spread like Wildfire? - Empirical Investigation of Information Propagation in Waiting Crowds
Full text linkInformation propagation in crowds tends to have a negative image. A common narrative is that information about a danger spreads like wildfire and leads to panic. In contrast, using person-to-person information sharing in crowd management as a complement to other communication channels has been discussed less. Even though previous research indicated that information does not propagate easily in crowds, more detailed research is lacking. In this study, two different experiments are presented to provide initial insights. In the main experiment, five groups of 33-41 participants took part in a total of 35 runs. In each run, a person in a waiting group was given a message or command that had to be passed on, whereby the knowledge about the task, the relevance of the message and the input side were varied. In the second experiment, this procedure was repeated with two larger groups of participants (n = 91 and n = 101). Overall, results showed that information propagated better when people were properly briefed on their task and have performed it several times. There was also a tendency for a higher density to foster faster propagation and for participants to rely on the spoken word rather than seeing a behavior performed. Yet, some participants did not receive the information at all or did not pass it on. In general, the direction of communication (e.g., back to front or left to right) was not always the same but information was usually passed along in a similar direction from where it came
Are Depth Field Cameras Preserving Anonymity?
Full text linkThis paper presents a preliminary study to assess the degree of anonymization provided by the use of depth field camera, for various degrees of pixelization.
First the passage of 24 participants under a depth field camera was recorded. Each of the corresponding video was degraded with various levels of pixelization. Then the videos were shown to a subset of 6 participants, using a dedicated software which presents the videos in random order, starting with the lowest resolution. Each participant had to recognize themself, and in order to achieve this goal, could progressively improve the resolution.
Our results question the fact that pixelization is the proper way to improve anonymity. Actually recognition seems to a large extend to be based on dynamic features rather than on the resolution of the picture. Besides we identify mostly 2 groups of responses: either the person can identify him/herself whatever the pixelization, or the recognition task is out of reach. Thus, the ability to use dynamic features could be person dependent. Further exploration would be useful to confirm this observation
Evacuation from Cramped Interiors with Aisle Seats: Uncertainty Induced by the Random Choice of Initial Positions
Full text linkConsidering evacuation from cramped interiors with aisle seats, the initial seating positions of pedestrians represent a non-negligible source of variance in total evacuation time. By means of Pathfinder simulations, this uncertainty is quantitatively investigated for a train and lecture hall geometry with homogeneous and heterogeneous groups of agents. Furthermore, an energy-inspired description of the occupation configuration is introduced that enables a proper numerical representation of the configuration space of the initial seating positions
Congestion Number Analysis of Cross-Flow Dynamics: Experimental Data and Simulations
Full text linkWe recently proposed the "Congestion Number" (CN) as a metricto evaluate the state of a pedestrian crowd. Such metric, whose definition is based on the gradient of the rotor of the crowd velocity field, appears to provide additional information with respect to traditional metrics based on pedestrian density and flow.
We also published two works on the dynamics of orthogonally crossing pedestrian flows under different density regimes. In the first manuscript we analysed experimental data by using traditionalobservables such as density, velocity and relative position between pedestrians, along with less explored ones such as body orientation. In the second one we proposed a hierarchy of simulation models to reproduce the cross-flow dynamics, and used the aforementioned observables to compare such models.
Based on theoretical considerations and analysis of real world data, we believe the crossing flow setting to be a good arena to test the CN metric, and in this work we perform a CN analysis on the empirical and simulation data. Results show that simulation models, which reproduced almost perfectly the density time dependence of the pedestrian crowd, fail to reproduce the CN one. Actually, models "outperform" the pedestrian crowd when analysed using CN. These preliminary results suggest that the CN metric may provide useful information not only in crowd assessment but also in model evaluation