VR Toolkit for Identifying Group Characteristics

Visualising crowds is a key pedestrian dynamics topic, with significant research efforts aiming to improve the current state-of-the-art. Sophisticated visualisation methods are a standard for modern commercial models, and can improve crowd management techniques and sociological theory development. These models often define standard metrics, including density and speed. However, modern visualisation techniques typically use desktop screens. This can limit the capability of a user to investigate and identify key features, especially in real time scenarios such as control centres. Virtual reality (VR) provides the opportunity to represent scenarios in a fully immersive environment, granting the user the ability to quickly assess situations. Furthermore, these visualisations are often limited to the simulation model that has generated the dataset, rather than being source-agnostic. In this paper we implement an immersive, interactive toolkit for crowd behaviour analysis. This toolkit was built specifically for use within VR environments and was developed in conjunction with commercial users and researchers. It allows the user to identify locations of interest, as well as individual agents, showing characteristics such as group density, individual (Voronoi) density and speed. Furthermore, it was used as a data-extraction tool, building individual fundamental diagrams for all scenario agents, and predicting group status as a function of local agent geometry. Finally, this paper presents an evaluation of the toolkit made by crowd behaviour experts

Looking at handaxes from another angle: Assessing the ergonomic and functional importance of edge form in Acheulean bifaces

Edge angle is widely considered to be a morphological attribute that influences the functional performance of lithic technologies. However, the comparative performance capabilities of handaxes that vary in terms of edge angles has never been investigated under experimental conditions. Similarly, detailed accounts of Acheulean handaxe angle variation from archaeological examples have not been reported in the literature. Consequently, it has not previously been possible to assess the extent to which Palaeolithic individuals adhered to specific edge angle ranges during handaxe production or whether resultant artifactual properties may have been in response to varying rates of utility. Here, using a substantial experimental program (n = 500 handaxes), we investigate the impact that edge angle variation has on the cutting efficiency of handaxes at a “whole tool” and “edge-point localized” level. We then examine edge angles in a temporally and geographically wide range of handaxes (n = 643) and assess the extent to which hominins were likely altering tool production choices in response to functional pressures. Our experimental results demonstrate that, up to a certain value, higher edge angles in handaxes can actually increase functional performance. Furthermore, results indicate that edges in the proximal portion of handaxes have the greatest influence over efficiency rates. Combined with examination of archaeological specimens, these results suggest that hominins actively pursued the production of more obtuse edges in the proximal (butt) portion of handaxes in order to increase ergonomic features that facilitated greater efficiency during use. Edge angle values in the proximal portion of the archaeological handaxes were, however, consistently found to be below an efficiency threshold identified at ?70 degrees, above which, an edge’s ability to effectively be applied to cutting tasks decreases markedly. This further suggests that the proximal edges of handaxes, at least occasionally, were required as a functional working edge

A Generalised Methodology for the Investigation of Human Behavioural Responses to Hostile Attacks

Terrorist attacks have become more frequent and more deadly in recent decades. Understanding the movement responses of the individuals involved can save lives. Pedestrian dynamics is an area of research and industry that investigates the movement of people. Using pedestrian dynamics to predict the responses to terrorist attacks could be hugely beneficial to the survival of those involved. This PhD developed a generalised methodology for investigating movement responses to terrorist attacks, accommodating the wide range of attack vectors seen in modern terrorism and providing a detailed summary of the data that should be obtained. Initial work analysed the overlap between pedestrian dynamics and terrorism. This concluded that current interdisciplinary research is not sufficiently advanced to allow for accurate predictions of pedestrian movement responses to terrorist attacks, due to a lack of usable data given the sensitivity of previous incidents and limitations on experimental methodologies. Two sets of experiments were then performed, examining responses to knife-based attacks by an unexpected and hostile individual. These experiments were split into physical reality (PR) and virtual reality (VR). The PR experiments were performed in December 2018 with 80 participants, and the VR experiments in January-February 2020 with 55 participants. The experiments obtained positional, physiological, psychological and memory-related measurements. Analysis of these datasets investigated the participant responses to hostile aggressors, including the impact of demographic, emotional state, and the similarity in responses between the VR and PR paradigms. The analysis on the psychological and physiological datasets proved a stressed response to the hostile individual, resulting in the first ever experimental dataset for these. The subsequent analysis on the positional and memory-related datasets provided key inputs for pedestrian dynamics models and concluded that VR is appropriate as a data-generating tool for human behaviour in emergencies.Open Acces

A quantification of the reliability of self-reports following a simulated stressful event

International audienceInterviews and surveys are the most commonly used data-gathering and data-generating techniques when investigating human behaviour in emergencies. However, these approaches suffer from several limitations, including potential errors in memory accuracy, a lack of quantitative reliability. This study focuses on a survey performed on participants who had taken part in a stressful experiment. The survey was carried out three months afterwards, asking them to recall their experience. Analysis of this data quantitatively assesses their recall, across multiple different domains. This study observed several differences between experimental and control group participants, as well as differences between participants in VR and Physical experimental groups. However, it observes no increase in confabulation as a result of increased stress. The outcome of this study is to provide insight into the quantitative reliability of interviews and surveys of people involved in emergencies