scholarly journals An Extension of the Exit Choice Model: Considering the Variance in the Perspectives of Evacuees When Interacting with the Spread of Fire

2021 ◽  
Vol 14 (1) ◽  
pp. 173
Author(s):  
Mohammed Mahmod Shuaib

Understanding evacuees’ responses to dynamic environmental changes, during an emergency evacuation, is of great importance in determining which aspects are ideal and which aspects should be eliminated or corrected. Evacuees differ in their ability to continually plan escape routes and adapt the routes chosen when they become unsafe owing to moving sources of threat. This is because they have different views and perspectives. The perspectives of evacuees are stochastic and are characterized by a high degree of uncertainty and complexity. To reduce the complexity and control of uncertainty, a model is proposed that can test for variant stochastic representations of evacuees’ perspectives. Two extremely realistic perspectives—the most ideal and the least ideal—are proposed to reasonably limit the range of variance. The success of achieving optimal evacuation is tested when different tendencies towards extreme perspectives are adopted. It is concluded that data toward the most ideal perspectives are capable of demonstrating safer evacuation by reducing the number of simulated burnt agents. This study enables crowd managers and fire safety researchers to test guidance systems as well as configuration of buildings using different perspectives of evacuees.

Author(s):  
S. Singh ◽  
M. Saberi

Abstract. Successful emergency evacuation of a large crowd depends on understanding human behaviour and its interaction with environmental stimuli in that situation. A careful study of human behaviour in these stressful and often time-bound situations can enable building designers to account for these effects to develop the most efficient evacuation strategies. One of the major roadblocks of the field has been the lack of reliable data collection techniques. Traditionally, most of the data analysed for these studies is either collected from historical events or through stated preference (SP) surveys given the challenges of conducting high-risk emergency evacuation experiments. The project is aimed at conducting emergency evacuation scenarios in a virtual reality (VR) environment. Eighty-four participants participated in multiple cases as a part of three VR scenarios to test various factors affecting their decision-making process. Participants were immersed in VR scenarios and subjected to a series of choices. Incorporation of VR technology enabled the experiment to record participants' stated preference with a much greater degree of certainty and realism as opposed to traditional pen and paper methods. The study devised a discrete choice model and calibrated it using the data obtained from the VR-based survey. When testing multiple competing factors in the VR scenarios and comparing the results with previous studies, in one VR scenario, the direction of exit signs was found more influential than crowding. In another scenario, familiarity with an exit appeared to be more influential than herding behaviour and exit distance. Overall, the VR technology is demonstrated to provide an advantage as a means to collect data and has come out as a promising tool to be incorporated in future emergency exit choice studies.


2021 ◽  
Vol 18 (6) ◽  
pp. 1405-1423
Author(s):  
Dariusz Strzyżowski ◽  
Elżbieta Gorczyca ◽  
Kazimierz Krzemień ◽  
Mirosław Żelazny

AbstractStrong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second- to third-order catchments with area ranging from 0.09 km2 to 0.8 km2. Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. We mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. We also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small (total area <100 m2) shallow landslides were created. The mean distance of bedload transport was similar (t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.


Author(s):  
Nicolae Boboc ◽  
◽  
Valentina Munteanu ◽  

The high degree of land use in the Republic of Moldova as a whole, and the Cogâlnic river basin in particular, imposes the need to assess the quality of the environment and the characteristics of the anthropogenic pressure on the landscapes in temporal and spatial dynamics and to identifying an adequate of measure system for the purpose to maintain/restore the optimal structure and functioning of landscape systems. Based from the Land Cadastre on data, statistical data of population censuses, bibliographic and cartographic sources, a system, was appraised a system of indicators(of naturalness, of artificialization of landscapes, environmental changes) and quantified human pressure on the environment through agriculture and anthropogenic pressure on forest landscapes from the Cogâlnic catchment area. The values of the indices and the human pressure on the landscapes were processed using GIS techniques and elaborated cartographic models.


2017 ◽  
Vol 28 (10) ◽  
pp. 1750128 ◽  
Author(s):  
Yongxing Li ◽  
Hongfei Jia ◽  
Jun Li ◽  
Jian Gong ◽  
Kechao Sun

Considering the process of pedestrian evacuation as pedestrian walking freely from current position to exit and queuing at the exit, estimated evacuation time model for single pedestrian is established. Based on estimated evacuation time and shortest distance, pedestrian exit choice model is established considering pedestrian preference. Pedestrian exit choice model is added into pedestrian simulation model which is built based on cellular automata. Pedestrian evacuation behavior in multi-exits case is simulated. The simulations indicate that pedestrian evacuation model built in our work describes the pedestrian evacuation behavior well.


2022 ◽  
Vol 2022 ◽  
pp. 1-16
Author(s):  
Sebastian-Camilo Vanegas-Ayala ◽  
Julio Barón-Velandia ◽  
Daniel-David Leal-Lara

Cultivating in greenhouses constitutes a fundamental tool for the development of high-quality crops with a high degree of profitability. Prediction and control models guarantee the correct management of environment variables, for which fuzzy inference systems have been successfully implemented. The purpose of this review is determining the various relationships in fuzzy inference systems currently used for the modelling, prediction, and control of humidity in greenhouses and how they have changed over time to be able to develop more robust and easier to understand models. The methodology follows the PRISMA work guide. A total of 93 investigations in 4 academic databases were reviewed; their bibliometric aspects, which contribute to the objective of the investigation, were extracted and analysed. It was finally concluded that the development of models based in Mamdani fuzzy inference systems, integrated with optimization and fuzzy clustering techniques, and following strategies such as model-based predictive control guarantee high levels of precision and interpretability.


1996 ◽  
Vol 429 ◽  
Author(s):  
Arun K. Nanda ◽  
Terrence J. Riley ◽  
Gary Miner ◽  
Michael F. Pas ◽  
Sylvia Hossain-Pas

AbstractUnder a joint development contract with Applied Materials (AMAT) and Texas Instruments (TI), SEMATECH undertook a project (Joint Development Project J100) with a goal of delivering a cost effective, technically advanced Rapid Thermal Processor (RTP). The RTP tool was specified to meet the present and future manufacturing needs of SEMATECH's member companies. The J100 results contained here will focus on the temperature and control performance of the AMAT RTP tool. The J100 results on the temperature measurement and control performance of AMAT's RTP tool using bare backside monitor wafers were presented in part I. In actual manufacturing environments the backside conditions of wafers are not consistent which causes temperature variations during rapid thermal processing. In this experiment, boron monitor wafers with varying backside conditions were used to test the uniformity, repeatability, and stability of the tool. The wafer backside films were fabricated using predictions from emissivity models and were subsequently verified by experimental techniques. In addition, perturbation experiments utilizing boron and arsenic implanted wafers demonstrated a high degree of localized temperature control across the wafers. A 3-sigma temperature variation ranging from 3.0 °C (for wafers with similar backside films) to 6.0 °C (for wafers with varying backside films) was found for all wafers processed during this evaluation. The perturbation experiments, which included a forced temperature offset of two degrees at one of the wafer temperature sensors, resulted in a noticeable change in sheet resistance across the wafer.


Antibiotics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 587
Author(s):  
Momna Rubab ◽  
Deog-Hwan Oh

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen that causes several gastrointestinal ailments in humans across the world. STEC’s ability to cause ailment is attributed to the presence of a broad range of known and putative virulence factors (VFs) including those that encode Shiga toxins. A total of 51 E. coli strains belonging to serogroups O26, O45, O103, O104, O113, O121, O145, and O157 were tested for the presence of nine VFs via PCR and for their susceptibility to 17 frequently used antibiotics using the disc diffusion method. The isolates belonged to eight different serotypes, including eight O serogroups and 12 H types. The frequency of the presence of key VFs were stx1 (76.47%), stx2 (86.27%), eae (100%), ehxA (98.03%), nleA (100%), ureC (94.11%), iha (96.07%), subA (9.80%), and saa (94.11%) in the E. coli strains. All E. coli strains carried seven or more distinct VFs and, among these, four isolates harbored all tested VFs. In addition, all E. coli strains had a high degree of antibiotic resistance and were multidrug resistant (MDR). These results show a high incidence frequency of VFs and heterogeneity of VFs and MDR profiles of E. coli strains. Moreover, half of the E. coli isolates (74.5%) were resistant to > 9 classes of antibiotics (more than 50% of the tested antibiotics). Thus, our findings highlight the importance of appropriate epidemiological and microbiological surveillance and control measures to prevent STEC disease in humans worldwide.


The Auk ◽  
2004 ◽  
Vol 121 (1) ◽  
pp. 230-242
Author(s):  
Erika S. Tavares ◽  
Carlos Yamashita ◽  
Cristina Y. Miyaki

Abstract The New World tribe Arini includes 30 genera and represents 148 known species of parrots. A previous phylogenetic study examined nine of those genera and suggested the existence of two groups. Our objective was to better understand the relationships among 14 species from 9 genera belonging to one of those groups. We partially sequenced the 12S and 16S ribosomal DNAs, cytochrome b, cytochrome oxidase I, and control region. We improved our understanding of the phylogenetic relationships among Neotropical parrots by adding both taxa and sequences, but the relationships among the deeper lineages were not well resolved. Our results agree with present classifications that place some species formerly in the genus Ara into three additional genera (Primolius, Orthopsittaca, and Diopsittaca). Additionally, we suggest that (1) D. nobilis and Guarouba guarouba are closely related and the genus Aratinga is not monophyletic; (2) diversification of genera may have occurred during the Miocene, and of species within genera during the Pliocene and Pleistocene; and (3) geologic, climatic, and environmental changes in South America may have been related to that diversification.


2005 ◽  
Vol 70 (1) ◽  
pp. 91-106 ◽  
Author(s):  
Steve Wolverton

Archaeological studies of temporal changes in human predation strategy using foraging theory tend to focus on the role of overexploitation of important prey resources and resulting resource depression. An alternative use of the prey-choice model framed under foraging theory is to investigate the influence of environmental changes, such as increases in climate stress, on prey availability. Environmental change can be expected to produce many of the same effects on human predation strategy as resource depression. Here analytical techniques typically used to study the effects of over-predation and resource depression caused by humans are used to monitor their response to fluctuations in prey availability related to climate change during the Holocene in Missouri. Data and interpretations presented here add to the growing body of zooarchaeological foraging theory literature implicating environmental change as a critical factor in human diet.


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