Research on Crowd Evacuation Simulation in Complex Mountainous Terrain Area Based on Cellular Automata

2014 ◽  
Vol 644-650 ◽  
pp. 1391-1395
Author(s):  
Bo Meng ◽  
Ting Liu ◽  
Na Lu

Recently, the variety of emergent events frequently occurring, such as: great environmental pollution, fire and explosion, toxic gas leakage, disserves human’s living environment, and huge economic and property losses, especially in the rural areas of mountain, where always surrounding by gas fields, chemical plants and other potentially dangerous source, the terrain of mountainous is complex, in the event of crises, the safe evacuation of the population will become a very critical issue. In this paper, through the analysis of the existing evacuation model based on the proposed application 3D surface cellular automata method simulation the evacuation processin complex mountainous terrain. The digital elevation model data, road network and characteristics of the pedestrian are integrated initiatively in the 3D surface CA model. The framework for data extraction, procession and application is designed. A Visualization Software System for three-dimensional simulation of pedestrian evacuation is developed. Moreover, through a case study of some gas well, which belongs to the Puguang gas field in the northeastern Sichuan, it is proved that the model presented in this paper can realize 3D simulation of pedestrian evacuation and predict evacuation time. At last the future work of the model is discussed.

Author(s):  
Zhuping Zhou ◽  
Yang Zhou ◽  
Ziyuan Pu ◽  
Yong Qi ◽  
Yongneng Xu

To simulate pedestrian evacuation processes on a metro station platform in a case of fire, a specific evacuation model is proposed, using an integrated cellular automata (CA) approach, in which the impacts from exits, other evacuees, and fire and smoke are included to measure the probability of the evacuee getting to each neighboring cell. The evacuation is firstly identified as a two-stage process including the motion on the platform and on the treads. Then the evacuation space is drawn to be a three-dimensional grid space, in which the cell size is defined by the stair structure and human body size. Based on that, this study proposes two CA models to simulate the evacuees’ movement and the smoke diffusion separately. Moreover, to describe the evacuation process in detail, the evacuation model is modified in three ways. First, transition rules in the evacuees’ movement model are embedded by social force theory to measure the impacts from the environment. Second, the smoke diffusion process is modified by considering the smoke control measures on the metro platform. Third, impact from smoke is quantified by the proportion of smoke in the centroid cell of evacuees. Finally, results from simulation experiments show that this model is able to recognize the arching and stagnation phenomenon at the foot of staircases, and the relations between the evacuation time and the crowd density for different parameters are also analyzed. The proposed method of simulating the pedestrian evacuation process can be useful in providing guiding principles for the software design of evacuation in metro systems.


2020 ◽  
Vol 29 (4) ◽  
pp. 741-757
Author(s):  
Kateryna Hazdiuk ◽  
◽  
Volodymyr Zhikharevich ◽  
Serhiy Ostapov ◽  
◽  
...  

This paper deals with the issue of model construction of the self-regeneration and self-replication processes using movable cellular automata (MCAs). The rules of cellular automaton (CA) interactions are found according to the concept of equilibrium neighborhood. The method is implemented by establishing these rules between different types of cellular automata (CAs). Several models for two- and three-dimensional cases are described, which depict both stable and unstable structures. As a result, computer models imitating such natural phenomena as self-replication and self-regeneration are obtained and graphically presented.


Machines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 13
Author(s):  
Yuhang Yang ◽  
Zhiqiao Dong ◽  
Yuquan Meng ◽  
Chenhui Shao

High-fidelity characterization and effective monitoring of spatial and spatiotemporal processes are crucial for high-performance quality control of many manufacturing processes and systems in the era of smart manufacturing. Although the recent development in measurement technologies has made it possible to acquire high-resolution three-dimensional (3D) surface measurement data, it is generally expensive and time-consuming to use such technologies in real-world production settings. Data-driven approaches that stem from statistics and machine learning can potentially enable intelligent, cost-effective surface measurement and thus allow manufacturers to use high-resolution surface data for better decision-making without introducing substantial production cost induced by data acquisition. Among these methods, spatial and spatiotemporal interpolation techniques can draw inferences about unmeasured locations on a surface using the measurement of other locations, thus decreasing the measurement cost and time. However, interpolation methods are very sensitive to the availability of measurement data, and their performances largely depend on the measurement scheme or the sampling design, i.e., how to allocate measurement efforts. As such, sampling design is considered to be another important field that enables intelligent surface measurement. This paper reviews and summarizes the state-of-the-art research in interpolation and sampling design for surface measurement in varied manufacturing applications. Research gaps and future research directions are also identified and can serve as a fundamental guideline to industrial practitioners and researchers for future studies in these areas.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 358 ◽  
Author(s):  
Chiara R. M. Brambilla ◽  
Ogochukwu Lilian Okafor-Muo ◽  
Hany Hassanin ◽  
Amr ElShaer

Three-dimensional (3D) printing is a recent technology, which gives the possibility to manufacture personalised dosage forms and it has a broad range of applications. One of the most developed, it is the manufacture of oral solid dosage and the four 3DP techniques which have been more used for their manufacture are FDM, inkjet 3DP, SLA and SLS. This systematic review is carried out to statistically analyze the current 3DP techniques employed in manufacturing oral solid formulations and assess the recent trends of this new technology. The work has been organised into four steps, (1) screening of the articles, definition of the inclusion and exclusion criteria and classification of the articles in the two main groups (included/excluded); (2) quantification and characterisation of the included articles; (3) evaluation of the validity of data and data extraction process; (4) data analysis, discussion, and conclusion to define which technique offers the best properties to be applied in the manufacture of oral solid formulations. It has been observed that with SLS 3DP technique, all the characterisation tests required by the BP (drug content, drug dissolution profile, hardness, friability, disintegration time and uniformity of weight) have been performed in the majority of articles, except for the friability test. However, it is not possible to define which of the four 3DP techniques is the most suitable for the manufacture of oral solid formulations, because the selection is affected by different parameters, such as the type of formulation, the physical-mechanical properties to achieve. Moreover, each technique has its specific advantages and disadvantages, such as for FDM the biggest challenge is the degradation of the drug, due to high printing temperature process or for SLA is the toxicity of the carcinogenic risk of the photopolymerising material.


2011 ◽  
Vol 368-373 ◽  
pp. 3602-3606
Author(s):  
Ze Xin Li ◽  
Min Chen

Underdeveloped rural areas have good but very vulnerable ecological environment, so the environment protection should be given priority in new rural construction. Based on the problems that rural areas have faced in ecological environment, some thoughts are given in this paper on ecological and environmental: ①To solve the conflicts between the development of rural economy and ecological environment protection, the development of eco-industry can be a key solution. ② For the point that people of underdeveloped areas live in scattered and small scale groups, which leads to difficulty in facility arrangements, some proposals are put forward on the construction of living environment in underdeveloped new rural areas.


Author(s):  
Yu Zhou ◽  
Chen Xuedong ◽  
Fan Zhichao ◽  
Jie Dong

Creep failure is one of the most important failure modes in the design of hydroprocessing reactors at elevated temperatures, and the accurate prediction of the creep behavior in structural discontinuities is a critical issue for component design. A physically-based continnum damage mechanics (CDM) model was adopted to describe all three creep stages of 2.25Cr-1Mo-0.25V ferritic steel widely used in manufacturing modern hydroprocessing reactors. The material constants in the damage constitutive equations were identified using an efficient optimization scheme based on genetic algorithm (GA). The user-defined subroutine implementing the CDM model was developed using user programmable features (UPFs) in ANSYS. Three-dimensional finite element analysis of the hydroprocessing reactor was conducted to determine the critical regions, and the studies on the stress redistribution and the prediction of damage evolution in these regions during creep were carried out. The results show that FE modelling based on CDM theory can provide a good tool for creep design of complex engineering components.


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