Ruggiero Lovreglio

The validation of evacuation simulation models through the analysis of behavioural uncertainty

Both experimental and simulation data on fire evacuation are influenced by a component of uncertainty caused by the impact of the unexplained variance in human behaviour, namely behavioural uncertainty (BU). Evacuation model validation studies should include the study of this type of uncertainty during the comparison of experiments and simulation results. An evacuation model validation procedure is introduced in this paper to study the impact of BU. This methodology is presented through a case study for the comparison between repeated experimental data and simulation results produced by FDS+Evac, an evacuation model for the simulation of human behaviour in fire, which makes use of distribution laws.

An Evacuation Decision Model based on perceived risk, social influence and behavioural uncertainty

The behaviour of people in the first stage of an evacuation can have a significant impact on the time required to reach a safe place. This behaviour is known in literature as pre-evacuation behaviour and it has been studied for many different evacuating scenarios. Despite the large number of studies, the representation of this behaviour is often oversimplified in most of the existing evacuation models. This paper aims to introduce a novel Evacuation Decision Model, allowing predicting the pre-evacuation state of an evacuee among three possible states (normal, investigation and evacuation) considering perceived risk for an evacuation scenario. The proposed model assumes that evacuees’ perceived risk is affected by several environmental and social cues as well as by demographics and personal characteristics of evacuees. The concept of behavioural uncertainty is also included in the model and a formulation to calibrate the proposed model using a likelihood function is then provided.

A dynamic approach for the impact of a toxic gas dispersion hazard considering human behaviour and dispersion modelling

The release of toxic gases due to natural/industrial accidents or terrorist attacks in populated areas can have tragic consequences. To prevent and evaluate the effects of these disasters different approaches and modelling tools have been introduced in the literature. These instruments are valuable tools for risk managers doing risk assessment of threatened areas. Despite the significant improvements in hazard assessment in case of toxic gas dispersion, these analyses do not generally include the impact of human behaviour and people movement during emergencies. This work aims at providing an approach which considers both modelling of gas dispersion and evacuation movement in order to improve the accuracy of risk assessment for disasters involving toxic gases. The approach is applied to a hypothetical scenario including a ship releasing Nitrogen dioxide (NO2) on a crowd attending a music festival. The difference between the results obtained with existing static methods (people do not move) and a dynamic approach (people move away from the danger) which considers people movement with different degrees of sophistication (either a simple linear path or more complex behavioural modelling) is discussed.

Dissuasive exit signage for building fire evacuation

This work presents the result of a questionnaire study which investigates the design of dissuasive emergency signage, i.e. signage conveying a message of not utilizing a specific exit door. The work analyses and tests a set of key features of dissuasive emergency signage using the Theory of Affordances. The variables having the largest impact on observer preference, interpretation and noticeability of the signage have been identified. Results show that features which clearly negate the exit-message of the original positive exit signage are most effective, for instance a red X-marking placed across the entirety of the exit signage conveys a clear dissuasive message. Other features of note are red flashing lights and alternation of colour. The sense of urgency conveyed by the sign is largely affected by sensory inputs such as red flashing lights or other features which cause the signs to break the tendencies of normalcy.

Application of the ordered logit model to optimising Frangi filter parameters for segmentation of perivascular spaces

Segmentation of perivascular spaces (PVS) from brain magnetic resonance images (MRI) is important for understanding the brains lymphatic system and its relationship with neurological diseases. The Frangi filter might be a valuable tool for this purpose. However, its parameters need to be adjusted in response to the variability in the scanners parameters and study protocols. Knowing the neuroradiological ratings of the PVS, we used the ordered logit model to optimise Frangi filter parameters. The PVS volume obtained significantly and strongly correlated with neuroradiological assessments (Spearmans ρ=0.75, p < 0.001), suggesting that the ordered logit model could be a good alternative to conventional optimisation frameworks for segmenting PVS on MRI.

Perivascular Spaces Segmentation in Brain MRI Using Optimal 3D Filtering

Perivascular Spaces (PVS) are a feature of Small Vessel Disease (SVD), and are an important part of the brain’s circulation and glymphatic drainage system. Quantitative analysis of PVS on Magnetic Resonance Images (MRI) is important for understanding their relationship with neurological diseases. In this work, we propose a segmentation technique based on the 3D Frangi filtering for extraction of PVS from MRI. We used ordered logit models and visual rating scales as alternative ground truth for Frangi filter parameter optimization and evaluation. We optimized and validated our proposed models on two independent cohorts, a dementia sample (N = 20) and patients who previously had mild to moderate stroke (N = 48). Results demonstrate the robustness and generalisability of our segmentation method. Segmentation-based PVS burden estimates correlated well with neuroradiological assessments (Spearman’s ρ = 0.74, p < 0.001), supporting the potential of our proposed method.

The Need for Enhancing Earthquake Evacuee Safety by Using Virtual Reality Serious Games

Enhancing evacuee safety is a key factor in reducing the number of injuries and deaths that result from earthquakes. This can be achieved by designing safer buildings taking into account behavioral factors and by training occupants. However, traditional approaches such as evacuation drills cannot be used in buildings in which occupants cannot easily leave the building (e.g. hospitals). In addition, these traditional approaches may not provide the intended learning outcomes and do not allow for the investigation of the impact of multiple evacuation factors on behavior. Virtual Reality (VR) and Serious Games (SG), i.e. games having education (in its various forms) as the primary goal, represent novel and effective alternatives to overcome the limitations of traditional approaches.We discuss the advantages and limitations of using VR SGs to investigate how building occupants behave during earthquake evacuations and to train building occupants to cope with such emergencies. We explore the key design components to develop the VR SG framework namely (a) what features constitute an earthquake event; (b) which types of buildings can be selected and how they should be represented within the VR environment; (c) how damage to the building is to be determined and represented; (d) what factors need to be included for agent behavior in earthquakes; and (e) what level of interaction should there be between agents and the human players. We highlight the important aspects that need to be addressed in further research to effectively develop VR SG tools for earthquake evacuation training.

Immersive virtual reality serious games for evacuation training and research: A systematic literature review

Abstract An appropriate and safe behavior for exiting a facility is key to reducing injuries and increasing survival when facing an emergency evacuation in a building. Knowledge on the best evacuation practice is commonly delivered by traditional training approaches such as videos, posters, or evacuation drills, but they may become ineffective in terms of knowledge acquisition and retention. Serious games (SGs) are an innovative approach devoted to training and educating people in a gaming environment. Recently, increasing attention has been paid to immersive virtual reality (IVR)-based SGs for evacuation knowledge delivery and behavior assessment because they are highly engaging and promote greater cognitive learning. This paper aims to understand the development and implementation of IVR SGs in the context of building evacuation training and research, applied to various indoor emergencies such as fire and earthquake. Thus, a conceptual framework for effective design and implementation through the systematic literature review method was developed. As a result, this framework integrates critical aspects and provides connections between them, including pedagogical and behavioral impacts, gaming environment development, and outcome and participation experience measures.

Prototyping virtual reality serious games for building earthquake preparedness: The Auckland City Hospital case study

Enhancing evacuee safety is a key factor in reducing the number of injuries and deaths that result from earthquakes. One way this can be achieved is by training occupants. Virtual Reality (VR) and Serious Games (SGs), represent novel techniques that may overcome the limitations of traditional training approaches. VR and SGs have been examined in the fire emergency context, however, their application to earthquake preparedness has not yet been extensively examined. We provide a theoretical discussion of the advantages and limitations of using VR SGs to investigate how building occupants behave during earthquake evacuations and to train building occupants to cope with such emergencies. We explore key design components for developing a VR SG framework: (a) what features constitute an earthquake event, (b) which building types can be selected and represented within the VR environment, (c) how damage to the building can be determined and represented, (d) how non-player characters (NPC) can be designed, and (e) what level of interaction there can be between NPC and the human participants. We illustrate the above by presenting the Auckland City Hospital, New Zealand as a case study, and propose a possible VR SG training tool to enhance earthquake preparedness in public buildings.