Research On Ecological Validity Evaluation And Improvement Methods Of Virtual Reality Based Indoor Evacuation Behavior Experiments

Emergency evacuation is an important part of the safety management of large public building.When the fire,explosion,earthquake and other emergencies occur,effective and ordered evacuation is the key factor to ensure the safety of trapped person and reduce casualties and damage.At present,the research methods adopted in emergency evacuation research such as case study,questionnaire,drill and simulation still have great limitations.The latest development of virtual reality technologies makes it possible to create immersive virtual environments and carry out evacuation behavior experiment,which provides a new promising approach for the emergency evacuation research.However,whether the ecological validity can meet the experimental requirements is the key factor affecting the authenticity,applicability and reasonability of the experimental results,which limits the wide application of virtual reality technologies in the field of emergency evacuation research.How to evaluate the ecological validity of virtual reality emergency evacuation experiment is the urgent problem needed to be solved in the field of virtual reality emergency evacuation research.Fire is the most common type of disaster in a variety of building hazards,and as the building environment becomes more complex and people gather more intensely,fire emergency evacuation environment is more complex,evacuation behavior is more representative.So in the setting of the building fire emergency,this study ensured the key factors influencing the sense of realism of virtual reality fire evacuation models,and then presented a method to establish the software system and hardware system of the virtual reality fire emergency evacuation models.As the sense of presence was the key factor influencing the ecological validity of virtual reality experiments and could be highly reflected by emotional response of experimental subjects,this study presented an approach integrating a set of subjective and objective measures including emotional scale and physiological indicators to evaluate the ecological validity of virtual reality experiments.And the effectiveness of the proposed approach was validated by virtual reality evaluation experiments.Finally,based on the individual evaluation mechanism,this study validated contrast effect among the sense of presence of subjects in virtual environments and presented methods to improve the ecological validity of virtual reality evacuation experiment.This study has solved key issues including modeling methods and ecological validity evaluation and improvement faced by emergency evacuation research,which provides scientific and reliable analytical methods for the further emergency evacuation research.Furthermore,it is of great significance for the study of the individual and group evacuation behaviors,understanding of the law of evacuation,prediction and management of the emergency evacuation process,evaluation and optimization of the emergency evacuation interventions,and enhancement of the emergency evacuation management level in la rge public buildings.