Extraction and quantitative analysis of microscopic evacuation characteristics based on digital image processing

Liu, Xuan; Song, Weiguo; Zhang, Jun

doi:10.1016/j.physa.2009.03.017

Cited by 160 publications

(74 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The movement direction is uniform in the undisturbed flow case and in the second case fluctuations of the angle can be noted. It is related to commonly observed people swaying at low movement speed and is referred to lateral oscillations [15,22]. Moreover, in the first 40 s (1,000 frames) of the crowded case duration (Fig.…”

Section: Methodsmentioning

confidence: 85%

Video analytics-based algorithm for monitoring egress from buildings

Szczodrak

Czyżewski

2014

Multimed Tools Appl

View full text Add to dashboard Cite

A concept and a practical implementation of the algorithm for detecting of potentially dangerous situations related to crowding in passages is presented. An example of such a situation is a crush which may be caused by an obstructed pedestrian pathway. The surveillance video camera signal analysis performed in the online mode is employed in order to detect hold-ups near bottlenecks like doorways or staircases. The details of the implemented algorithm which uses the optical flow method combined with fuzzy logic are explained. The experiments were carried out on a set of gathered video recordings from the surveillance camera installed in the campus of Gdansk University of Technology. The results of experiments performed on gathered video recordings shows high efficiency of the algorithm.

show abstract

Section: Methodsmentioning

confidence: 85%

Video analytics-based algorithm for monitoring egress from buildings

Szczodrak

Czyżewski

2014

Multimed Tools Appl

View full text Add to dashboard Cite

show abstract

“…Previous study carried out by Song and coworkers [25] and Hoogendoorn and Daamen [26] indicated that the step frequency is about 2 Hz in normal situation. However, pedestrians would increase their step frequency when egress in emergency, especially in fire.…”

Section: Movement Speedmentioning

confidence: 93%

A Multi-Grid Model for Evacuation Coupling with the Effects of Fire Products

et al. 2010

Self Cite

View full text Add to dashboard Cite

In the study, influences of fire products on pedestrians are introduced into a multi-grid evacuation model, in which the space is discretized into small grids with the size of 0.1 m 9 0.1 m and each pedestrian occupies 5 9 5 grid sites. The fire products affect two walking parameters of pedestrians: the desired movement direction and the step frequency. The data of fire products are obtained from the simulation results of the Fire Dynamics Simulator (FDS), a well-founded computational fluid dynamic (CFD) program, developed by the National Institute of Standards and Technology (NIST). With this model, we investigated the routes of pedestrians in fires, and the evacuation times in scenarios with different fire intensities, pre-movement times or door widths. The results indicate that pedestrians will avoid moving towards the fire source, small fire may make egress process faster while large fire may reduce evacuation efficiency significantly, the movement time increases rapidly with the increasing pre-movement time, and the door width plays a more important role for evacuation in fire than normal condition. Furthermore, for the evacuation from a hall with two exits our model can reproduce the inefficient use of exits and predict the optimal condition that results in least evacuation time.

show abstract

“…In the last two decades, many experimental technologies or simulative models, such as the technique of video capture [32] and the compressible hydrodynamic models [33], proposed in this field have been successfully applied to simulate the evacuation processes of pedestrians in the case of emergency situations [34,35]. Among these studies, the development in the field of transportation engineering is outstanding.…”

Section: Human Induced Structural Vibrations and Human Behaviorsmentioning

confidence: 99%

Pedestrian Induced Structural Vibration and the Walking Force Models Basing On Biomechanics: a Literature Review

Song¹,

Zhang²

2015

Proceedings of the 5th International Conference on Advanced Design and Manufacturing Engineering

View full text Add to dashboard Cite

Abstract. The interactions of structure-human and those of human-human would change the macroscopic behavior of human walking on the structure and which, would further result the change of walking forces. The complexity of walking forces during the interaction process is the reason that lively structures exhibit some special vibration behaviors under the crowd excitation. The walking forces observed through the traditional indoor footfall experiments can't fully reflect the interaction process. However, a biomechanics based walking force models can establish the relationships between human macroscopic activities and walking forces so that it can server as an alternative method. The biomechanical models describing human body dynamics and walking forces are reviewed and the problems to be studied in the field are suggested from the views point of human-human interaction and human-structure interaction. IntroductionThe pedestrians induced structural vibrations is a worldly focused problem and which is widely solved by the forced vibration theory (FVT). However, recent studies have shown that some special structural vibration phenomena under crowds' excitation are resulted by human-human interaction (HHI) and human-structure interaction (HSI). These two interactions would change the normal gaits of human and further result the change of frequency, amplitude and phase of walking forces. However, the indoor footfall tests can't fully consider the influences of the interactions because of the experimental conditions. Combining the simulation of pedestrians' macroscopic movements, the biomechanics based walking force model (BWFM) could serve as an alternative solution.The studies on human induced structural vibrations, human behaviors on pedestrian structures and BWFMs are reviewed in this paper. From view point of HHI and HSI, four important aspects associated with BWFMs are summarized as follows:(1) The study of walking forces on a moving surface.(2) The study of walking forces under different walking velocities.(3) The study of walking forces under the change of walking directions.(4) The study of walking forces considering the human synchronization. Human induced structural vibrations and human behaviorsHuman induced structural vibrations is a widely concerned problem [1,2], and the forced vibration theory (FVT) which is a primary analytical method has been used in varies standards domestic and overseas [3,4]. According to this theory, the walking forces are treated as external excitations, and the pedestrians induced vibrations are solved through forced vibration equations. Based on this theory, some similar methods have been developed, such as the time history method [5], the dynamic amplifying factor method [6], the response spectra method [7], and others [1,8]. In these methods the walking forces are treated as external excitations and obtained from indoor footfall experiments, while the body weight is treated as the added mass [9]. During the footfall experiments, testers are required to walk in a customary way...

show abstract

Extraction and quantitative analysis of microscopic evacuation characteristics based on digital image processing

Cited by 160 publications

References 30 publications

Video analytics-based algorithm for monitoring egress from buildings

Video analytics-based algorithm for monitoring egress from buildings

A Multi-Grid Model for Evacuation Coupling with the Effects of Fire Products

Pedestrian Induced Structural Vibration and the Walking Force Models Basing On Biomechanics: a Literature Review

Contact Info

Product

Resources

About