Article

A model for evacuation risk assessment with consideration of pre- and post-disaster factors

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Abstract

In urban areas, the occurrence of disasters can cause extensive damage to human society. For this reason, evacuation, regarded as a critical course of action to relocate people and property, helps to alleviate loss of life and property to a great extent. Risk associated with evacuation is an abstract concept that cannot be easily conceptualized. This paper develops a model for assessing and visualizing the risks associated with the evacuation process in response to potential catastrophes. Understanding of evacuation risk, the potential for losing transport connections and the difficulty of transferring rescue resources, was previously limited by considering pre-disaster factors only. This study mitigates such limitation by extending previous research to include the contingent post-disaster factors that have received scant attention to date. Two contingent post-disaster factors: the spatial impact of the disaster and the potential for traffic congestion caused by the evacuee routing behaviors, are discussed in detail and integrated into the model along with other pre-disaster factors. A case study on the transportation network of Beijing, China is used to demonstrate the value of the model. This paper asserts that the notion of evacuation risk is not a static evaluation of such factors as road vulnerability; rather it involves a dynamic process where contingent factors associated with disastrous events play a role. This model can help city emergency planners to identify urban infrastructures that may hinder an efficient evacuation process because of their deficient configuration.

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... The first one regards the extent of disaster impacts. Natural disasters tend to affect extensive areas [2] and are more complex and variable in shape [3]. Man-made disasters, on the other hand, can be seen as single-source catastrophes which extend to their surrounding area [2,3]. ...
... Natural disasters tend to affect extensive areas [2] and are more complex and variable in shape [3]. Man-made disasters, on the other hand, can be seen as single-source catastrophes which extend to their surrounding area [2,3]. The second one refers to the impact magnitude. ...
... The second one refers to the impact magnitude. Natural disasters generally have an even impact over the affected area, while the impact of man-made disasters is more concentrated on the origin node [2]. The third difference concerns the occurrence of timing and progression of the phenomenon. ...
Article
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Despite their inherent vulnerability to structural and functional degradation, transportation networks play a vital role in the aftermath of disasters by ensuring physical access to the affected communities and providing services according to the generated needs. In this setting of operational conditions and service needs which deviate from normal, a restructuring of network functions is deemed to be beneficial for overall network serviceability. In such context, this paper explores the planning of post-disaster operations on a network following a hazardous event on one of the network’s nodes. Lane reversal, demand regulation and path activation are applied to provide an optimally reconfigured network with reallocated demand, so that the network performance is maximized. The problem is formulated as a bi-level optimization model; the upper level determines the optimal network management strategy implementation scheme while the lower level assigns traffic on the network. Three performance indices are used for that purpose: the total network travel time (TNTT), the total network flow (TNF) and the special origin-destination pair (OD pair) accessibility. A genetic algorithm coupled with a traffic assignment process is used as a solution methodology. Application of the model on a real urban network proves the computational efficiency of the algorithm; the model systematically produces robust results of enhanced network performance, indicating its value as an operation planning tool.
... Today, the pre-disaster (proactive) studies such as decrease of losses-damages, preparedness, early warning, estimation and understanding the disasters in the places subjected to the disaster are defined as ''Risk Management'' in the understanding of Disaster Management; after-disaster studies such as definition and analysis of the effect, intervention, improvement, restructuring are accepted as ''Crisis Management'' [2,3]. Within this context, Disaster Management studies are accepted as cycle and cover all activities including predisaster, during disaster and after-disaster [4]. In parallel to the developments regarding to this subject in the world, these may be defined as positive developments devoted to prevention of negative results of big scaled natural disasters that may occur in the future that the terms such as ''Protection of Natural Sources'', ''Sustainable Development'' and ''Disaster Management'' are in demand, international meeting organizations, agreements concluded and precautions taken. ...
... 3 The studies including design, material and standards of the buildings resistant to the earthquake will be supported. 4 In order to that current earthquake engineering laboratory will give more efficiently and as open to everybody, a coordinated system will be established. 5 The current earthquake code Eurocode will be followed, updated and developed. ...
... 3 For risky individual groups, a special arrangement will be done. 4 Obligatory Earthquake Insurance will be expanded. ...
Article
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Natural disasters are known as natural events that usually abrupt and occurs in certain periods, cannot be stopped, causing loss of life, destruction of property and the environment and affecting negatory social life and economy. In the last quarter of the past century, "Response" and "Recovery" activities were the reactional efforts of minimizing the losses caused by natural disasters. Since the beginning of this century, they share their place with proactive efforts as Risk Assessment, Mitigation/Prevention and Preparedness. Due to these developments, to coordinate and arrange the disaster management initiatives and activities, several laws were issued, new institutions were set and new plans and strategies have been developed. In this study, the endeavors like researches, planning and settling strategies to minimize the negative consequences of natural disasters, particularly earthquakes and flooding, are classified in the legislative context.
... The tendency of natural disasters and their impacts on critical infrastructure are increasing (EM-DAT, 2018;Kadri et al., 2014;Munich RE, 2018;Oh, 2010). These effects are enhanced due to progressive urban development in disaster-prone areas (Chen et al., 2012). Critical infrastructure is of fundamental significance in modern societies' unobstructed functioning of day-to-day life and if disrupted, can have severe negative consequences on security and well-being (Urlainis et al., 2014). ...
... Evacuation is the most important strategy for saving human lives, by leaving an endangered area and reaching an evacuation zone (Charnkol and Tanaboriboon, 2006;Chen et al., 2012;Shuto, 2005). Typically, natural disasters lead to the evacuation of large population masses (Buckle, 2012). ...
... Many situational factors, including official warnings and instructions, time of day and day of week, the presence of family members or behaviour of the social environment, influence the decision-making process, whether to evacuate or not, and the response to an impending hazardous event. Hence, evacuation is a complex and dynamic process and may also increase the risk for the affected people (Buckle, 2012;Charnakol and Tanaboriboon, 2006;Chen, 2012;Quarantelli, 1980;Quarantelli, 1990;Ramos, 2016). ...
Conference Paper
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In rapid-onset disasters the time needed for evacuation is crucial. Aside from the behaviour of the population, the road network plays a fundamental role. It serves as a medium to reach a safe area. This study analyses the entire evacuation process, from decision-making up to the arrival at an evacuation zone by combining standardised questionnaires and GIS-based simulation. Based on a case study in the Chilean community of Talcahuano, an event-based past scenario and a hypothetical future scenario is investigated, integrating the affected population in the research process. The main problem identified in past evacuations has been time delay due to congestions, which also is evident in the results of the hypothetical future scenario. A result which supports evacuation by foot. This paper argues that a combination of scientific methods is essential for analysing evacuation and to reduce the risk due to time delay, critical route and transport medium choice. KEYWORDS Interdisciplinary approach, case study, evacuation, tsunami, recommendations, disaster risk management 497 Kubisch et al. Analysis of evacuation in natural disasters CoRe Paper-Planning, Foresight and Risk Analysis
... This worst-case analysis relies on normative models under the constraints of travel environment (e.g., road capacity, travel demand). For example, the integral accessibility measurement can be employed to estimate the worst-case scenario of how link failures could impact other parts of the road network [23,24]; critical infrastructure, in terms of vital transport nodes/links, can be identified by modeling the highest potential loss of efficiency in highway networks [25,26]; vulnerable roads can be identified by heuristic models that demarcate at-risk neighborhoods [27][28][29][30]. A subsequent mapping of the vulnerability in the context of GIS can further help identify the deficiencies in road networks that may hinder efficient evacuations [27]. ...
... This section proposes the Evacuation Vulnerability Model (EVM) to illustrate and evaluate the road network vulnerability faced by evacuees and first responders in no-notice evacuations. The model is extended from the Critical Cluster Model (CCM) that estimates evacuation vulnerability at the neighborhood scale [27][28][29][30]. In the model, the difficulty of movement in an evacuation is considered to be access to and from nodes in a network-based travel environment. ...
... In a no-notice evacuation, driving directions are rigorously restricted; and, in this case, eligible exits are defined as the road segments that permit only outbound travel. This restriction can also be found in variations of the CCM [29,30]. Figure 1 illustrates an example of this outbound evacuation vulnerability for node A, the anchor node in the sample network. ...
Article
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The concept of vulnerability has been employed to develop transport systems that sustain devastating disasters and ensure the efficient evacuation of neighborhoods. Existing studies of road network vulnerability overlook two important aspects of analysis: the no-notice evacuation and the different objectives of evacuees and first responders. First, a no-notice evacuation leaves limited time for proactive emergency planning; therefore, rescue strategies in this scenario rely heavily on real-time traffic information. Second, the goal of first responders in an evacuation is to move into an affected area immediately after a hazardous event unfolds, and the risk they face differs from that of evacuees. To this end, this paper develops a network-based model to evaluate vulnerability during a no-notice evacuation and applies it to a case study in Dublin, OH, USA. The model is suited to assessing network vulnerability in response to events with uncertainty and coordinating traffic control strategies in a no-notice evacuation. This study can become a valuable complement to the methodological conceptualization of vulnerability and can provide insights into developing comprehensive emergency management plans.
... It is expected that smart cities will treat emergencies in a way that disasters are avoided and thus this is the primary objective of emergencies management systems. However, when untreated emergencies become disasters, some specialized solutions may still be employed, and there are many works in the literature that have addressed particular problems of preand post-disaster scenarios [27], [36]; ...
... Actually, there is a gray area in the literature considering how critical situations persist in a city. In some perspectives, a critical situation that last for some time may be considered as a pre-disaster period [36], [70] or even a post-disaster situation [71], [72]. On the other hand, the duration of a critical situation may roughly be the duration of an emergency that can still be addressed before a disaster is formally defined, as expressed in the management cycle in Figure 3. ...
... However, notifications can also provide relevant information about the type of an emergency and its intensity, as well as information to guide people to move toward a safer place [28]. Additionally, when considering notification strategies, safety plans have been also employed in many localities, with people being previously trained about the procedures to be taken after being alerted about an emergency [36], [200]. Whatever the case, alerting affected people is a major issue of emergencies management systems, with different particularities to be considered. ...
Article
Full-text available
The rapid urbanization process in the last century has deeply changed the way we live and interact with each other. As most people now live in urban areas, cities are experiencing growing demands for more efficient and sustainable public services that may improve the perceived quality of life, specially with the anticipated impacts of climatic changes. In this already complex scenario with increasingly overcrowded urban areas, different types of emergency situations may happen anywhere and anytime, with unpredictable costs in human lives and economic losses. In order to cope with unexpected and potentially dangerous emergencies, smart cities initiatives have been developed in different cities, addressing multiple aspects of emergencies detection, alerting, and mitigation. In this context, this article surveys recent smart city solutions for crisis management, proposing definitions for emergencies-oriented systems and classifying them according to the employed technologies and provided services. Additionally, recent developments in the domains of Internet of Things, Artificial Intelligence and Big Data are also highlighted when associated to the management of urban emergencies, potentially paving the way for new developments while classifying and organizing them according to different criteria. Finally, open research challenges will be identified, indicating promising trends and research directions for the coming years.
... The tendency of natural disasters and their impacts on critical infrastructure are increasing (EM-DAT, 2018;Kadri et al., 2014;Munich RE, 2018;Oh, 2010). These effects are enhanced due to progressive urban development in disaster-prone areas (Chen et al., 2012). Critical infrastructure is of fundamental significance in modern societies' unobstructed functioning of day-to-day life and if disrupted, can have severe negative consequences on security and well-being (Urlainis et al., 2014). ...
... Evacuation is the most important strategy for saving human lives, by leaving an endangered area and reaching an evacuation zone (Charnkol and Tanaboriboon, 2006;Chen et al., 2012;Shuto, 2005). Typically, natural disasters lead to the evacuation of large population masses (Buckle, 2012). ...
... Many situational factors, including official warnings and instructions, time of day and day of week, the presence of family members or behaviour of the social environment, influence the decision-making process, whether to evacuate or not, and the response to an impending hazardous event. Hence, evacuation is a complex and dynamic process and may also increase the risk for the affected people (Buckle, 2012;Charnakol and Tanaboriboon, 2006;Chen, 2012;Quarantelli, 1980;Quarantelli, 1990;Ramos, 2016). ...
Conference Paper
Full-text available
In rapid-onset disasters the time needed for evacuation is crucial. Aside from the behaviour of the population, the road network plays a fundamental role. It serves as a medium to reach a safe area. This study analyses the entire evacuation process, from decision-making up to the arrival at an evacuation zone by combining standardised questionnaires and GIS-based simulation. Based on a case study in the Chilean community of Talcahuano, an event-based past scenario and a hypothetical future scenario is investigated, integrating the affected population in the research process. The main problem identified in past evacuations has been time delay due to congestions, which also is evident in the results of the hypothetical future scenario. A result which supports evacuation by foot. This paper argues that a combination of scientific methods is essential for analysing evacuation and to reduce the risk due to time delay, critical route and transport medium choice. KEYWORDS Interdisciplinary approach, case study, evacuation, tsunami, recommendations, disaster risk management 497 Kubisch et al. Analysis of evacuation in natural disasters CoRe Paper-Planning, Foresight and Risk Analysis
... Pidd, et al. [56] developed a prototype spatial decision support system, where a geographical information system was integrated with an object-oriented micro-simulator to perform the population evacuation simulation. Chen, et al. [6] proposed a simulation model considering factors, such as evacuee behavior and traffic congestion, to evaluate the related evacuation risks. Cristiani and Peri [10] employed simulation methods to investigate the role of obstacles in evacuation events. ...
... Three objectives are determined for the optimization of the evacuation at metro stations, i.e., the evacuation time, density, and cost. Since the rule "the less the better" applies to all three objectives, the optimization rule can be expressed as in Eq. (6). Besides, there is usually a standard for the evacuation time, indicating that an evacuation can be regarded as a successful one as long as the evacuation is completed within the standard. ...
... The emergency exits 01 and 02 in Fig. 9 (b) and the emergency stairs 05 and 06 in Fig. 9 (a) (indicated by the numbers 19 and 20 in parentheses) are not available in the actual station, and they are built in the simulation model to assess the influence on the evacuation optimization. Cost for the renovation of x 5_2 10,000 $ c 6 Cost for the renovation of x 6 3000 $ c 7 Cost for the renovation of x 7 2000 $ c 9 Cost for the renovation of x 9 100,000 $ Note: Cost for the influential factors are based on the local conditions. ...
Article
Evacuation is critical for safety management due to the highly overcrowded passengers in the metro stations. A simulation-based approach integrating Random Forest (RF) and Non-dominated Sorting Genetic Algorithm III (NSGA-III) is proposed to perform the evacuation evaluation and optimization at metro stations. A 3D model of the metro station is built to simulate the dynamic process of passenger evacuation in metro stations. A framework consisting of 9 influential factors and 3 objectives is developed to model the input-output relationship in passenger evacuation. An RF-based meta-model is used to construct the relationship between influential factors and objectives. At last, NSGA-III is applied to seeking the optimal solutions for the station renovation in order to achieve a safe evacuation. A station model simulating a real metro station in Singapore is constructed to test the effectiveness and applicability of the proposed approach. It is found that (1) A safe evacuation could be achieved for the station, but along with the increasing passenger volume and panic level, the requirement of evacuation objectives, the evacuation time and density, may not be met. Especially under the high passenger volume conditions, the passenger density could reach up to 6.2 unit/m² (extremely dangerous); (2) An average improvement degree, 7.5%, can be achieved for the optimization of 20 test cases, and a maximum improvement degree, 22.5%, can be achieved for the evacuation optimization at metro stations; (3) It could be difficult to keep both of the evacuation time and density within the standards if one major exit is closed, even after the optimization. But a larger average improvement degree, 10.8%, can be achieved by the proposed optimization approach, which indicates the optimal solutions still could reduce the risk to a great extent. The novelty of this research lies in that (a) An RF algorithm is incorporated to build the meta-model that can properly represent the relationship between influential factors and objectives, despite the complexity and even conflicting between them; (b) Optimal measures for the evacuation improvement are provided from the MOO perspective by integrating NSGA-III. This hybrid approach can be used as a decision tool to assist regulatory authorities in developing effective emergency evacuation evaluation and optimization plans with adequate consideration of the complexity and multi-objective nature under evacuation events.
... There are several existing studies on the risk analysis after a disaster occurs (City of Nagoya 2015; Church and Cova 2000;Chen et al. 2012;Silva et al. 2014). In Japan, a certain municipality, e.g., Nagoya city, has been evaluating the regional risks, road blockage probabilities, after occurrence of a large-scale disaster (City of Nagoya 2015). ...
... Church and Cova map evacuation risks on transportation networks using a spatial optimization model, called critical cluster model, in which the whole area is divided into multiple small areas and small areas with high ratio of population to exit capacity are regarded as those with high evacuation risk (Church and Cova 2000). Since the model in (Church and Cova 2000) is only based on pre-disaster factors, i.e., population and exit capacity, Chen et al. extend this model by adding postdisaster factors, e.g., spatial impact of disaster and potential traffic jams caused by evacuation guiding (Chen et al. 2012). In this paper, we improve the safety of evacuation guiding by taking into account of pre-disaster factor, i.e. road blockage probability. ...
Article
Full-text available
It has been highly expected to achieve speedy and reliable evacuation guiding under large scale disasters. As for the speedy evacuation, an automatic evacuation guiding scheme has been proposed, which is a reactive approach based on implicit interactions among evacuees, their mobile devices, and networks. In this scheme, an evacuation route is given by the shortest path, which may not be safe. In this paper, we propose a speedy and reliable path selection based on the geographical risk map for the existing automatic evacuation guiding, which is a proactive approach that allows evacuees to evacuate speedily while avoiding encounters with blocked road segments as much as possible. First, the proposed scheme enumerates candidates of short paths from the evacuee’s current location to the refuge. Then, it selects the most reliable one from the candidates by taking into account road blockage probabilities, each of which is an estimated probability that the corresponding road is blocked under a certain disaster. Through simulation experiments, we show that the proposed scheme can improve the safety of evacuation in terms of the number of encounters with blocked road segments while keeping both the average and maximum evacuation times unchanged, compared with the shortest path selection. We further demonstrate how the proactive function, i.e., geographical risk analysis, and the reactive function, i.e., information sharing, contribute to the system performance.
... In order to evaluate the clearing time of the evacuated residential area, they used data regarding the evacuated population (estimated on the basis of the number of houses and the average ratio of residents per home), the number of vehicles available to evacuate people, and the exit capacity of the roads serving traffic within the endangered area. With the CCM in mind, Chen (Chen, Kwan, Li, & Chen, 2012) analyses the process of evacuation by taking into account Dijkstra's algorithm, while Shahabi and Wilson (2014) offer the modelling of evacuation in urban settings by means of the CASPER algorithm. Finally, there are publications that refer to the support of evacuation processes by implementing appropriate management strategies. ...
... In the subject literature, there have hitherto been several attempts to create a model simulating the evacuation from flood-risk areas, e.g. in the works by Uno and Kashiyama (2008) and Chen (Chen et al., 2012). In this case, however, the determination of evacuation routes was based on Dijkstra's algorithm (in which the weight functions on the graph edges are represented by distance) (Dijkstra, 1959). ...
Article
The main purpose of the article is to develop an optimisation pattern for the process of a preventive evacuation of people from flood-risk areas (at the first sign of a flood), aimed at mitigating the negative effects of the flood performed through the application of modern computer tools. It has been assumed that the use of both GIS tools and apps for vehicle traffic modelling (the research includes the use of a method developed by the authors) in emergency procedures implemented in response to a flood may increase the efficiency of the anti-flood campaign (here: the evacuation of residents from flooded areas), and thus, it may also minimise the negative effects of the flooding itself. The article distinguishes 14 stages of research, which were chiefly completed by means of the following methods: distance-based accessibility, cumulative accessibility, the Enhanced Two-Step Floating Catchment Area Method (E2SFCA) and the Two-Step Floating Catchment Area Method (2SFCA), the vehicle routing method, algorithms by Dinitz, Edmonds-Karp, and Ford-Fulkerson, and a comparative method applied to draw a comparison between the actual state of affairs and the optimum condition determined by the aforementioned methods.
... Evacuation is a necessary public safety measure to reduce the health risks associated with significant accidents [4]. Eviction is an essential part of emergency response and management because it allows people to move from dangerous areas to safer ones [5]. ...
... For the study of SEC functional relationship, Chen [4] and Silvius [46] summarized and demonstrated the specific functional relationship and proved its accuracy. The SEC is expressed by the following Equation: ...
Article
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During a fire evacuation, long lateral evacuation distances, large crowds waiting for evacuation at the same level, and easily panicked populations are common. This research aimed to look into the large-scale evacuation behavior of urban underground complexes with limited evacuation and egress during a fire. A simplified model for large-scale group evacuation of urban subsurface complexes was constructed using system dynamics theory. The Vensim software was used for quantitative simulation. The model could represent the typical phenomenon of group evacuation behaviors, such as quick or slow, under seven operating situations with total initial numbers of 350, 400, 450, 500, 1000, 2000, and 4000. The results of an analysis of critical affecting factors show “total initial number” and “panic state” during a large-scale group evacuation: a large beginning population will result in a rapid reduction in system evacuation capability, delaying the completion of the evacuation process significantly; meanwhile, if the level of panic is deficient, the system’s evacuation efficiency will remain low for an extended period, making it difficult to evacuate trapped persons promptly. According to the findings, the developed system dynamics model, which combines the advantages of a continuous model with the advantages of a discrete model, is very accurate. At the same time, we should emphasize the importance of the evacuation guide and reinforce the fire education and behavior drills for the building’s workers. This research presents a simplified model for the evacuation of large groups of people from metropolitan underground complexes. Furthermore, the findings may give theoretical support for the development of rules and safety management practices.
... The seemingly free-flowing crowd actually has a particular preference for certain paths, referred to as the path selection behavior. The path selection behavior becomes more prominent in emergency situations such as overcrowding [24]. This path selection behavior has To estimate the spatial distribution of the crowd population in open public places, we have proposed a new interpolation method called the inverse distance weighting method based on path selection behavior (IDWPSB). ...
Article
Full-text available
Urban open places with a public service function (e.g., urban parks) are likely to be populated in peak hours and during public events. To mitigate the risk of overcrowding and even events of stampedes, it is of considerable significance to realize a real-time full coverage estimate of the population density. The main challenge has been the limited deployment of crowd surveillance detectors in open public spaces, leading to incomplete data coverage and thus impacting the quality and reliability of the density estimation. To remedy this issue, this paper proposes a modified inverse distance weighting (IDW) method, named the inverse distance weighting based on path selection behavior (IDWPSB) method. The proposed IDWPSB method adjusts the distance decay effect according to visitors’ path selection behavior, which better characterizes the human dynamics in open spaces. By implementing the model in a real-world road network in the Shichahai scenic area in Beijing, China, the study shows a decrease in the absolute deviation by 17.62% comparing the results between the new method and the traditional IDW method, justifying the effectiveness of the new method for spatial interpolation in open public places. By considering the behavioral factor, the proposed IDWPSB method can provide insights into public safety management with the increasing availability of data derived from location-based services.
... For a road segment, congestion occurs when evacuation demand assigned to it exceeds its carrying capacity (Qian et al., 2006). On a regional scale, the ratio between road carrying capacity and demand, also known as the Bulk Lane Demand (BLD), could, therefore, express the level of crowdedness or congestion (Chen et al., 2012). It is expressed by: ...
Preprint
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Understanding the spatiotemporal road network accessibility during a hurricane evacuation, the level of ease of residents in an area in reaching evacuation destination sites through the road network, is a critical component of emergency management. While many studies have attempted to measure road accessibility (either in the scope of evacuation or beyond), few have considered both dynamic evacuation demand and characteristics of a hurricane. This study proposes a methodological framework to achieve this goal. In an interval of every six hours, the method first estimates the evacuation demand in terms of number of vehicles per household in each county subdivision by considering the hurricane's wind radius and track. The closest facility analysis is then employed to model evacuees' route choices towards the predefined evacuation destinations. The potential crowdedness index (PCI), a metric capturing the level of crowdedness of each road segment, is then computed by coupling the estimated evacuation demand and route choices. Finally, the road accessibility of each sub-county is measured by calculating the reciprocal of the sum of PCI values of corresponding roads connecting evacuees from the sub-county to the designated destinations. The method is applied to the entire state of Florida during Hurricane Irma in September 2017. Results show that I-75 and I-95 northbound have a high level of congestion, and sub-counties along the northbound I-95 suffer from the worst road accessibility. In addition, this research performs a sensitivity analysis for examining the impacts of different choices of behavioral response curves on accessibility results.
... An important and appreciated hazard assessment model for evacuation risk is the Critical Cluster Model developed and presented by Cova and Church in 1997 and tested in 2002 by Cova and Johnson. Various implementations and completion of the original idea were made, considering routing behaviors (Chen et al., 2012), application in public bus network or in emergency traffic . ...
Article
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Unforeseen Evacuation Vulnerability Assessment for Targu-Mures Using Critical Cluster Model. As safety becomes a very important concept the evolving society want to offer proper procedures to keep the population in safe and to rise the sense of security in people. With all these unforeseen hazardous events are present in everyday life and their proper handling is important. One of the first things that should be known is how vulnerable are certain locations regarding evacuation, where may appear bottlenecks if a crowd want to leave a place. This research's objective is to apply the Critical Cluster Model for an important city of Romania (Targu-Mures) modeling the population distribution and the predicted traffic flow through different scenarios. Through this the Critical Cluster Model becomes more powerful as not only the population that are in buildings is taken account but also the people being in traffic. As result we could have identified the most vulnerable intersections in the city for different day times and for different evacuation distances. We also have identified, which are the locations where the vulnerability significantly changes over a day and in which direction. The results emphasize that the hidden attributes of a structurally visible network, such as road direction, capacity, traffic flow, population distribution are very important factors in unforeseen evacuation vulnerability assessment.
... Evacuation is a necessary action in reducing the devastating consequences of a disaster. Evacuation, as Chen et al. (2012) put it, can be an immediate coordinated response to a disaster, if residents are well-prepared before the event. During the evacuation, communities are supposed to secure their safety, rescue and aid others if needed, and help extinguish small fires on their own. ...
Article
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Background. The significance of mutual-help in communities for disaster management is a fundamental important concept. However, the current societal state does not reflect this lesson. S&G (Simulation and Gaming) has the potential to overcome the challenges faced in promoting community-based disaster management. No scientific research is currently present that reviews their achievements in Japan. Aim. This paper analyzes the current achievements of S&G in enhancing community resilience against large-scale earthquakes in Japan. Method. The paper clarifies the theoretical advantages of S&G in enhancing community resilience in coping and adaptive capacity plus proposes a conceptual contribution framework of S&G in improving community resilience. Based on this framework, the paper analyzes some major games that tackle community resilience against earthquakes in Japan. Results. The paper demonstrates the achievements through the S&G spectrum that stresses the disastrous experience with specific resilience views on one side, while decision making for critical reflection from other players with more comprehensive resilience views on the other side. Conclusion. The paper showcases the current S&G achievements in enhancing community resilience against large-scale earthquakes in Japan using the proposed framework, which can be utilized by other disaster-prone countries to develop and evaluate applications of S&G for increasing community resilience against earthquakes.
... The Spatial Structure Plan determines the hierarchy of service centres and relationships among different spatial units, while the Spatial Pattern Plan regulates land uses such as conservation, cultivation and builtup areas. In principal, the Spatial Pattern Plan should take into consideration, among other matters, hydro-meteorological hazards, particularly in planning the land use in the coastal regions to reduce negative impacts of disasters before, during, and after their occurrence [11,29,30] and improve local resilience [31]. Spatial planning strategies can vary from avoiding potential direct impacts, relocating vulnerable people to less risky locations, and modifying environmental design, to maintaining good spatial management [32]. ...
Article
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Global warming has negatively influenced the quality of life of many people, especially those who live in coastal areas. Sea-level-rise in northern Java, Indonesia, has impacted coastal cities prone to flooding and inundation. This study reports the extent to which spatial planning, mandated by the Indonesian Law 26/2007 to minimise the risk of people and improve their resilience, has taken into account hydro-meteorological hazard of Semarang City in northern Java. Geographic Information System (GIS) based spatial analyses were used to predict the anticipated vulnerability of the area based on the combined effect of two processes, namely, a tendency towards land subsidence and an increase in sea level. Further, by overlaying the current and projected vulnerability maps to the year 2031 with the planned land use of the city in the same timeframes, results show that most precincts with anticipated flooding and inundation are residential, industrial, and commercial areas, indicating that the current spatial land use plan has not adequately accounted for the hazard. The methodology employed in this study should prove of use for other cities on the littoral.
... It breaks from the common linear characterization of agent-environment relations (An 2012) in agent based models and provides a comprehensive description of supply and demand dynamics. Further it moves beyond short-term evacuation and emergency responses (e.g.Chen et al., 2012) and takes a long-term view of urban recovery. In addition, while agent based models of urban growth and land use change (e.g.Huang et al. 2014) are spatially explicit and integrative (for example housing land markets), models of the labor market often treat the market as a-spatial and isolated(Deissenberg et al. 2008;Martin & Neugart 2009;Dawid et al. 2012). ...
Article
We present an economic definition of cascading effects of a disaster on the labor market over the medium to long term. Cascading effects are considered events that alter local amenities. In the context of the labor market, the standard conception of a cascade as a sequence of events that alter the capital stock, may not be very instructive as the immediate time horizon is not the relevant economic timeframe. We outline some of the theoretical implications arising from this definition and give them some intuition based on an agent based simulation model. The model is used to simulate two cascade-type scenarios following an earthquake in the city of Jerusalem. Results indicate that a strong cascading effect in the labor market depends on serious functional change in the physical environment i.e. land-use change. Flow-related changes in labor and population movement are less likely to create effects that cascade into other sub-markets. Implications of these findings point to the key role of labor mobility as workers seek solutions outside the area struck by disaster.
... Le but étant d'évaluer la performance d'un réseau en situation perturbée, de mesurer l'intensité des pertes de service du système de transport et d'estimer la vitesse de restauration des flux (Chang et Nojima, 2001 ;Chang, 2003 ;Sohn et al., 2003 ;Bono et Gutiérrez, 2011 ;Nakanishi et al., 2013). Ce type d'application sous-entend l'urgence de la mise en sécurité des biens et des personnes en situation de crise et la gestion des évacuations via les réseaux de transport disponibles (Chen et al., 2012 ;Lambert et al., 2013 ;Mei et al., 2013). L'accessibilité du réseau routier peut également être utilisée pour soutenir la gestion de crise et la planification d'urgence (Léone et al., 2013). ...
Thesis
Les Alpes sont très impactées par les laves torrentielles déclenchées par de fortes pluies et la fonte des neiges. Certains événements dommageables au réseau de transport ont entrainé d’importantes répercussions socio-économiques. En raison de l’enclavement de nombreuses vallées dans les Alpes, la perturbation des réseaux routiers n’affecte pas seulement la zone endommagée, mais s’étend à tous les domaines et les activités qui en dépendent. L’objectif de cette thèse était de mener une analyse systémique du risque-réseau articulée autour de toutes les étapes du risque. Nous avons retenu trois bassins-versants situés sur des axes routiers à fort enjeux territoriaux dans les Alpes françaises. La méthode combinait plusieurs approches : 1) une analyse statistique des pluies associée aux évènements dommageables, 2) la modélisation des écoulements torrentiels liée à l’endommagement physique, 3) la comparaison des protocoles de gestion de crise routière théorique avec la réalité du terrain à la suite d’un évènement dommageable, 4) la modélisation des perturbations fonctionnelles au-delà de la zone impactée. Cette thèse a mis en évidence les facteurs aggravants de vulnérabilité structurelle du réseau ; elle explique la planification des actions mise en place lors de l’évènement dommageable sur le Rif Blanc le 4 juin 2012. Enfin, elle a permis d’estimer les pertes d’accessibilité territoriale à différentes échelles spatiales.
... For a road segment, congestion occurs when evacuation demand assigned to it exceeds its carrying capacity (Qian et al., 2006). On a regional scale, the ratio between road carrying capacity and demand, also known as the Bulk Lane Demand (BLD), could, therefore, express the level of crowdedness or congestion (Chen et al., 2012). It is expressed by: ...
Article
Full-text available
Understanding the spatio-temporal road network accessibility during a hurricane evacuation—the level of ease of residents in an area in reaching evacuation destination sites through the road network—is a critical component of emergency management. While many studies have attempted to measure road accessibility (either in the scope of evacuation or beyond), few have considered both dynamic evacuation demand and characteristics of a hurricane. This study proposes a methodological framework to achieve this goal. In an interval of every six hours, the method first estimates the evacuation demand in terms of number of vehicles per household in each county subdivision (sub-county) by considering the hurricane’s wind radius and track. The closest facility analysis is then employed to model evacuees’ route choices towards the predefined evacuation destinations. The potential crowdedness index (PCI), a metric capturing the level of crowdedness of each road segment, is then computed by coupling the estimated evacuation demand and route choices. Finally, the road accessibility of each sub-county is measured by calculating the reciprocal of the sum of PCI values of corresponding roads connecting evacuees from the sub-county to the designated destinations. The method is applied to the entire state of Florida during Hurricane Irma in September 2017. Results show that I-75 and I-95 northbound have a high level of congestion, and sub-counties along the northbound I-95 suffer from the worst road accessibility. In addition, this research performs a sensitivity analysis for examining the impacts of different choices of behavioral response curves on accessibility results.
... To improve the accuracy of simulation results, we require qualitative and quantitative data from a crowd in an actual earthquake emergency response. Qualitative data include the response behavior of pedestrians, man-environmental interactions [8][9] and chronological decision-making processes of organizations at different evacuation stages [10][11]. Quantitative data include delay time, evacuation speed [12], evacuation route choices [13][14] and evacuation exit choices [11]. ...
Article
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With the booming development of evacuation simulation software, developing an extensive database in indoor scenarios for evacuation models is imperative. In this paper, we conduct a qualitative and quantitative analysis of the collected videotapes and aim to provide a complete and unitary database of pedestrians’ earthquake emergency response behaviors in indoor scenarios, including human-environment interactions. Using the qualitative analysis method, we extract keyword groups and keywords that code the response modes of pedestrians and construct a general decision flowchart using chronological organization. Using the quantitative analysis method, we analyze data on the delay time, evacuation speed, evacuation route and emergency exit choices. Furthermore, we study the effect of classroom layout on emergency evacuation. The database for indoor scenarios provides reliable input parameters and allows the construction of real and effective constraints for use in software and mathematical models. The database can also be used to validate the accuracy of evacuation models.
... First it breaks from the common linear characterization of agent-environment relations [15] in AB models and provides a comprehensive description of supply and demand dynamics. Second, it moves beyond evacuation and emergency responses [16,17] and takes a longer long-term view of urban recovery. Third, while AB models of urban growth and land use change [18][19][20] are spatially explicit and integrative (for example, treating housing land markets), AB models of the labor market often treat the market as a-spatial and isolated [21][22][23]. ...
Article
This paper presents two opposite perspectives on the labor market in the aftermath of a disaster. The first posits a production sector that is non-tradeable and a labor market with total mobility. This is modeled using agent based simulation. The second presents a production sector that is fully tradeable and a labor market that is perfectly immobile. This is modeled using traditional micro-economic modeling and numerical simulation. Outcomes from the two approaches are compared. In the no-disaster case, participation rates and wages under both approaches settle down to a low-level equilibrium albeit at different rates. In the case of a disaster, outcomes are very different. Under the agent based model labor market mobility results in solutions being found outside the area. In the micro-economic approach workers absorb the recovery process within the area readjusting their demand for labor. When population movement is introduced the system reorganizes at a new equilibrium. The results highlight first, the importance of labor mobility and flexibility and second, the divergent absorption costs in determining the long-term outcomes of a disaster.
... In recent years, decision behavior of earthquake emergency response has attracted increasing attention from researchers. Chen et al. [4,5] considered three factors to reduce seismic risk in evacuation models which were site hazard (H), building vulnerability (V) and exposed elements (E). Prati et al. [6] had found that the most frequent behavioral responses during the Emilia-Romagna earthquake on 20 May 2012 in Italy were moving to another room, escaping from home, and waiting in bed. ...
Article
After the earthquake, the correct and efficient earthquake emergency response modes of individuals are crucial for reducing casualties. Based on the keyword database of the earthquake emergency response behaviors of individuals, this research used the machine learning method to construct a decision tree of the earthquake emergency response modes. Through the decision tree, this study extracted decision rules that can predict the emergency response decisions of individuals in future earthquake and also determined the relative importance of six different factors (Seismic intensity > Social context >Location>Action>Age>Gender) in determining response behaviors. The set of rules was quite effective when evaluated using the test individuals with an overall accuracy of 85.23%. And then, combined with the cultural background in China, we had extracted and analyzed the main response modes of individuals at seismic intensities I-V, VI, VII, VIII-IX stricken regions by earthquake. The decision rules and main response modes of individuals were scientific bases for the targeted earthquake emergency safety education and the government emergency rescue.
... Size, population density and degree of urbanization are relevant aspects for understanding hazard, vulnerability and resilience (Cross, 2001). The definition of escape routes considers not only safe roads but also whether it is appropriate for a population contingent (Chen et al., 2012). These routes need to be defined according to the population contingent that will use them in the disaster emergency (Zhang et al., 2013). ...
Article
Purpose This paper aims to shed some light on the distribution of population, living in disaster risk areas in Brazil, on the intra-urban scale. The following three aspects are evaluated in this paper: the distribution of exposed population according to municipal size classification; the population density in disaster risk areas; and the municipal human development classification for the municipalities with disaster risk areas. Design/methodology/approach This research is based on an explorative approach. The main database used is a result of the association of landslide and flood risk areas to demographic census, available for 825 Brazilian municipalities. Additional databases were integrated to characterize disaster risk management and municipal human development. Findings The results revealed that the population exposed to disaster areas is concentrated within the capitals and small cities in the country. Moreover, disaster risk areas are densely populated even in small cities, suggesting that it is a reality faced not only by the larger cities. Finally, disaster risk areas exist even inside municipalities with a high level of human development. Practical implications These findings could contribute to the understanding of the spatialisation of disaster risk in Brazil, a primordial step for the reduction of human losses. Originality/value A novel perspective about the Brazilian population exposed to disaster risk was obtained, revealing a current issue faced by the municipalities independent of the size classification and level of human development.
... In contrast, the generated model diagrams act as guidelines both to enable decision-makers to recognize all the useful information for specific tasks and to determine the impact of information for the existing tasks. These findings can also assist in supporting and improving the use of the analytical models proposed in previous studies [4,26]. This can be done by pointing out the data sources that can provide the information required by decision-makers. ...
Article
Full-text available
With the emergence of big data and new data sources, a challenge posed to today’s organizations consists of identifying how to align their decision-making and organizational processes to data that could help them make better-informed decisions. This paper presents a study in the context of disaster management in Brazil that applies oDMN +, a framework that connects decision-making with data sources through an extended modeling notation and a modeling process. The study results revealed that the framework is an effective approach for improving the understanding of how to leverage big data in the organization’s decision-making.
... The impacts of disaster chains or secondary disasters on evacuation are also generally ignored. Thus, in models optimizing evacuation path, it is necessary to evaluate the disaster itself and the impact range of secondary disasters, and then take the robustness of the scheme as a constraint condition to modify when seeking the optimal scheme (Chen et al., 2012;Gai et al., 2018). Furthermore, owing to environmental differences, the characteristics of pedestrian behavior in different areas are totally different and require separate study. ...
Article
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Computer-based simulation is a means of exploring complex systems and has become the mainstream method of pedestrian research. In this research, a multi-agent simulation model of pedestrian flow will be established using a multi-agent system (MAS) and Bayesian Nash equilibrium. MAS is used to simulate the crowd movement and the interaction between pedestrians, and Bayesian Nash equilibrium is adopted to analyze the decision-making process of pedestrians. In contrast to previous pedestrian flow simulation modeling methods, this study adopts multi-agent modeling to realize the complete heterogeneity of pedestrians, so as to achieve more accurate simulation and make the research conclusions closer to reality. To be specific, we attempt to determine the cell side length and simulation time step of an initial model parameterized using a dataset of actual pedestrian movements. It allows more than one pedestrian to be in the same cell and stipulates that the utility of pedestrians decreases with the growing number of pedestrians in the cell. The Bayesian Nash equilibrium is applied to analyze the decision-making process of pedestrians and collision avoidance rules and interaction rules of agents are also formulated. A number of areas of further research are discussed.
... However, when a disaster occurs, even though there are predefined shelters such as schools, communal halls, libraries, and other buildings, in many cases, people have an instinctive feeling as to the direction of safety [1]. They tend to move away from danger and towards destinations perceived as safe [2]. In addition to that, the evacuation behaviors also depend on whether all shelters in the surrounding area can provide refuge for people at a reasonable evacuation distance and time immediately after a disaster [3,4]. ...
Article
Full-text available
Under normal circumstances, people’s homes and work locations are given by their addresses, and this information is used to create a disaster management plan in which there are instructions to individuals on how to evacuate. However, when a disaster strikes, some shelters are destroyed, or in some cases, distance from affected areas to the closest shelter is not reasonable, or people have no possibility to act rationally as a natural response to physical danger, and hence, the evacuation plan is not followed. In each of these situations, people tend to find alternative places to stay, and the evacuees in shelters do not represent the total number of the displaced population. Knowing the spatial distribution of total displaced people (including people in shelters and other places) is very important for the success of the response activities which, among other measures, aims to provide for the basic humanitarian needs of affected people. Traditional methods of people displacement estimation are based on population surveys in the shelters. However, conducting a survey is infeasible to perform at scale and provides low coverage, i.e., can only cover the numbers for the population that are at the shelters, and the information cannot be delivered in a timely fashion. Therefore, in this research, anonymized mobile Call Detail Records (CDRs) are proposed as a source of information to infer the spatial distribution of the displaced population by analyzing the variation of home cell-tower for each anonymized mobile phone subscriber before and after a disaster. The effectiveness of the proposed method is evaluated using remote-sensing-based building damage assessment data and Displacement Tracking Matrix (DTM) from an individual’s questionnaire survey conducted after a severe cyclone in Beira city, central Mozambique, in March 2019. The results show an encouraging correlation coefficient (over 70%) between the number of arrivals in each neighborhood estimated using CDRs and from DTM. In addition to this, CDRs derive spatial distribution of displaced populations with high coverage of people, i.e., including not only people in the shelter but everyone who used a mobile phone before and after the disaster. Moreover, results suggest that if CDRs data are available right after a disaster, population displacement can be estimated, and this information can be used for response activities and hence contribute to reducing waterborne diseases (e.g., diarrheal disease) and diseases associated with crowding (e.g., acute respiratory infections) in shelters and host communities.
... Several approaches have been developed to model evacuation (Hamacher and Tjandra 2001, Lindell et al.), including static routing models (Bayram et al. 2015, Chen et al. 2012, Cova and Johnson 2003, Yamada 1996, dynamic routing models (Achrekar and Vogiatzis 2018, Ogier 1988, Opasanon and Miller-Hooks 2010, Xie et al. 2010, and simulation-based evacuation planning (Chen et al. 2006, Chen and Zhan 2014, Ebihara et al. 1992, Gao et al. 2010. Evacuation models could be categorized as macroscopic and microscopic (Hamacher and Tjandra 2002). ...
Preprint
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As the number of adopted alternative fuel vehicles increases, communities that are susceptible to hazardous events, such as hurricanes and wildfires, need to create new evacuation plans that account for their refueling needs. During emergencies that require preemptive evacuation, drivers using alternative fuel vehicles are left vulnerable under conventional evacuation routes which do not provide access to refueling stations on their way to shelters. In this paper, we formulate a novel evacuation routing problem which considers multiple types of fuel vehicles. Specifically, we introduce a $k$-spanning evacuation tree problem with hop constraints that capture the refueling needs of each vehicle fuel type $k \in K$ as they are routed to a shelter. We provide a mixed integer mathematical formulation for the problem along with a path-based reformulation which allows us to create a column-generation based matheuristic to efficiently solve the problem. Next, we apply the proposed framework to the Sioux Falls transportation network considering that refueling stations for alternative fuel vehicles are placed to serve habitual demands. We present a series of numerical experiments where we discuss optimal travel and refueling times under different driving ranges for each vehicle type. Our findings show that the characteristics of each vehicle fuel type (driving range and infrastructure siting) play a pivotal role in determining the optimal evacuation trees. Evacuation routes that are optimal for one type of vehicles are often infeasible for the remaining vehicles; furthermore, driving range constraints and the need to refuel could force evacuees to detour prior to reaching safety.
... From the mathematical point of view, the simulation of a system and the management of flows (goods, vehicles, and resources) correspond to the resolution of the canonical four-stage model (emission, destination, modal and route choice) and as highlighted in Fig. 2. The approach to be followed is strongly conditioned by the event, the effects that it can trigger on the transport systems, and the interactions among the different activities that persist in the area. Many authors dealt with emergency conditions both in the preventive and post-catastrophe phases [9] and following the principle of evacuation planning (EP) some guides have been drawn up such as the more generic cases developed by Russo and Rindone [6], [10] or more specific formulations as seen in Wei et al. [11] and Chen et al. [12], such as the tools for the mobilization of emergency teams [13] or even case studies for planning or verifying the evacuation of areas subject to disasters [14]- [16]. ...
... An agent-based model (ABM) is a micro-scale model that simulates the synchronous interactions of agents based on pre-defined rules (Wooldridge 2009). ABMs have been integrated into social network science to enhance the understanding of human behaviors (Chen et al. 2012). In a networkbased ABM, each agent can be represented as a node, which interacts with other agents under predefined behavioral assumptions in an abstracted interaction network (Cardinot et al. 2019). ...
Article
Full-text available
As the COVID-19 vaccination has been quickly rolling out around the globe, the evaluation of the effects of vaccinating populations for the safe reopening of schools has become a focal point for educators, decision-makers, and the general public. Within this context, we develop a contact network agent-based model (CN-ABM) to simulate on-campus disease transmission scenarios. The CN-ABM establishes contact networks for agents based on their daily activity patterns, evaluates the agents’ health status change in different activity environments, and then simulates the epidemic curve. By applying the model to a real-world campus environment, we identify how different community risk levels, teaching modalities, and vaccination rates would shape the epidemic curve. The results show that without vaccination, retaining under 50% of on-campus students can largely flatten the curve, and having 25% on-campus students can achieve the best result (peak value < 1%). With vaccination, having a maximum of 75% on-campus students and at least a 45% vaccination rate can suppress the curve, and a 65% vaccination rate can achieve the best result. The developed CN-ABM can be employed to assist local government and school officials with developing proactive intervention strategies to safely reopen schools.
... Numerous studies exist; for example see Dawson, Peppe, and Wang (2011) on flooding, Chen and Zhan (2008) on fires, Crooks and Wise (2013) on earthquakes, Park, Tsang, Sun, and Glasser (2012) on terrorism and Salze et al. (2014) on industrial accidents. Much of this interest is in the shortterm, evacuation and recovery aspects of the disaster with an emphasis on route optimization and emergency management (Chen, Kwan, Qiang, & Chen, 2012;Zimmerman et al., 2010). ...
Article
An agent based model for assessing the welfare impacts of urban disasters is presented. This couples a population allocation algorithm with a simulation platform. The fully articulated model fuses both bottom-up (locational choice for workplace, residence and daily activities) and top-down (land use and housing price) protocols. This study moves beyond current research by addressing economic welfare consequences of urban disasters. The resilience capabilities of different income groups are identified. This is illustrated for the Jerusalem central business district. Empirical results at the micro-scale suggest that physical destruction leads to a zero-sum game within the housing market in which wealthier residents hold an advantage over the poor. This results in the transformation of neighborhoods and displacement of poor and vulnerable populations. Low income groups lose both physical ground and the social support systems that go with location. Policy implications of these findings are discussed.
... Evacuation plans and rescuers' emergency activities' definition are aimed at reducing the exposure factor E through management strategies (Chen, Kwan, Li, & Chen, 2012). Evacuation plans' definition strictly depends on national and local regulations, which, over the decades, adopt this strategy as an important risk reduction tool (Federal Emergency Management Agency, 1996; Italian technical commission for seismic micro-zoning, 2014). ...
Article
In earthquake disasters, the leading causes of death are directly related both to build collapses and fatalities during the following evacuation phase. Allowing people to autonomously gain safe areas and assembly points should be the basis for reducing human losses in urban systems. However, some important environmental and behavioural factors (e.g. vulnerability of buildings, compact urban fabric, cascade effects, presence of people unfamiliar with the urban layout, absence of information on evacuation paths) can hinder this ‘self-help’-based evacuation process. This issue is really important in historical centres where evacuees suffer a combination of unfavourable conditions to safely escape. This paper concerns a non-invasive solution for guiding people along probable safe evacuation routes in earthquake emergency. The proposed Seismic Pedestrians' Evacuation Dynamic Guidance Expert System (SpeedGuides) considers the influence of the main environmental and behavioural safety factors for evacuees (i.e. street vulnerability, street blockages probability, crowding conditions along paths, presence of mortal dangers, visibility conditions) and combines them in a safety index through the Multi-criteria techniques application. SpeedGuides dynamically collects safety factor data during the time and suggests the possible safest path to the nearest secure zone according to the Dijkstra's algorithm approach. SpeedGuides is an easy-to-use model proposed for application on personal devices (e.g. smartphone) that, taking advantage of different expert methods, allows evacuees to simple enhance their safety. A first effectiveness evaluation of SpeedGuides is provided through an earthquake pedestrians' evacuation simulator in a significant case study. The evacuee performances (with and without the proposed guidance tool) are compared and discussed. Results demonstrate how individuals' safety levels are increased when evacuees use SpeedGuides.
Article
Significant work has sought to improve our understanding of critical infrastructure dependencies. Efforts have focused on the importance (weight) of the connections between infrastructures, mitigating damage, and prioritizing responses after failures. Less research has been completed to understand how critical infrastructure dependencies impact the ability to complete successful evacuations. Focusing on three critical infrastructures-transportation, communication, and energy-this study proposes and reports results of a methodology to assign weight to the value of connections between infrastructures necessary for evacuations. Establishing values to weight infrastructure linkages will identify the most vital connections relevant to evacuations. This allows planners to prioritize improvements and mitigations, as well as identify locations for deploying emergency services to facilitate a timely evacuation. A fictitious evacuation was simulated using the Real time evacuation Planning Model (RtePM). Model results show the effects of communication outages resulting in changes to evacuation response and the effects of power outages resulting in changes to roadway access that require power. The output of the model allows compilation of rankings between infrastructure connections and a better understanding of the effects critical infrastructures have on an evacuation. This methodology aids decision makers in resiliency and mitigation planning to avoid unanticipated cascading failures across dependent infrastructures that inhibit effective evacuations.
Article
One of the necessary measures to mitigate and manage the social impacts of seismic events is evacuation and emergency shelter planning. Such plans should be developed before disasters by relevant agencies with the participation of local communities, especially in densely populated urban areas. In this study, having a look at the experiences relevant to emergency sheltering process in Iran and other countries, an applicable model for site selection will be presented. For this purpose, the main characteristics of suitable public places to be used as the emergency shelter after a disaster will be addressed. In addition, minimum requirements to adopt public sites as emergency shelters will be discussed, based on socio-economic and physical vulnerability factors focusing on Iran's cities. Accordingly, necessary parameters for emergency shelter planning will be outlined and weighted using experts' judgments. Then, a multi-criteria index based model for site selection of emergency shelters is proposed based on earthquake risk, physical vulnerability, and social and environmental parameters. Finally, the model is applied in district one of Karaj city and appropriate places for emergency shelter are selected accordingly. The proposed model in this study could be useful for decision makers in disaster management planning in Iran and can be applied in other countries by calibrating the parameters and their weights based on local conditions.
Article
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Due to the frequently occurring disasters in the world, emergency management is an attractive research area aiming to stabilize the disasters and reduce the potential damage to human, facility and environment. The timely and effective emergency management is highly relied on the utilization of observable information and the integration of available resources. Computational intelligence is one of the fastest growing areas in the field of computer technology. Nowadays, big data has brought ever-increasing impact and challenge to effective data processing and intelligent decision-making. Computation intelligence technologies play a vital role during the lifecycle of emergency management in the context of big data. This review provides a comprehensive survey of state-of-the-art computation intelligence technologies widely applied in the emergency management, and summarizes the present-day emergency management systems in diverse industries. Finally, some promising future research directions and challenges are indicated.
Conference Paper
When large-scale disasters occur, evacuees have to evacuate to a refuge quickly. For this purpose, there has been proposed an automatic evacuation guiding scheme based on implicit interactions among evacuees, their mobile devices, and networks. In this scheme, an evacuation route is obtained as the shortest path, which may not be safe. In this paper, we propose a short and reliable path selection for existing automatic evacuation guiding, which allows evacuees to evacuate quickly while avoiding encounters with blocked road segments as much as possible. First, the proposed scheme calculates k-shortest \((k \ge 1)\) paths from the current location to the destination, with the help of the existing algorithm. Then, it selects the most reliable one from the candidates by taking into account road blockage probabilities, each of which is an estimated probability that the corresponding road is blocked under a certain disaster. Through simulation experiments, we show that the proposed scheme can reduce the number of encounters with blocked road segments with an appropriate value of k, while keeping the average/maximum evacuation time compared with the shortest path selection.
Article
How to evacuate evacuees to safety from islands in disasters is an important issue for the emergency system design of an offshore airport. In this paper, a modeling framework was developed to evaluate and optimize the emergency evacuation capability of an offshore airport. With this framework, the emergency evacuation capability was evaluated and optimized in the context of the cross-sea bridge failure for Dalian International Airport, Dalian, China. With the combination of an evacuation demand analysis and a marine network analysis, a scheduling simulation was developed to evaluate the capability of the marine evacuation system plan under emergency. Based on the evaluation results, two optimization strategies were introduced to improve this plan. The evaluation results show that the emergency evacuation capability of an offshore airport is mainly limited by the marine traffic environment of the urban area in the condition of bridge failure. To improve the emergency evacuation capability, some vessels should be located at the offshore airport, and a wharf should be constructed in the nearby mainland. The current results of this study will be helpful in guiding the emergency evacuation system design of an artificial or a natural island.
Article
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Purpose The aim of this study was to determine the number of shelters, specify some optimal paths among building blocks towards shelters, and assign population to shelters. Design/methodology/approach Imperialist competition algorithm (ICA) and particle swarm optimization (PSO) were used to optimize the objectives of this study. Findings The optimal value for PSO objective function was with the number of function evaluations (NFE) of 5300 and the optimal value of ICA objective function was with NFE of 1062. Repetition test for both algorithms showed that imperialist competition algorithm enjoys better stability and constancy and higher speed of convergence compared to particle swarm algorithm. This has been also shown in larger environments. 92% of the existing populations have access to shelters at a distance of less than600 meters. This means that evacuation from the building blocks to shelters takes less than 8 minutes. The average distance from a block (for example, a residential complex) to an optimal shelter is approximately273meters. The greatest risk of route and shelter has been 239 and 121, respectively. Research limitations/implications To address these goals, four following objective functions were considered: a) minimization of the distance for getting all the people to shelters b) the lowest total risk of the discharge path c) minimization of the total time required to transfer people to shelters or hospitals if necessary, and d) the lowest total risk in shelters. Social implications Over the recent decades, the frequency of so-called ‘natural’ disasters has increased significantly worldwide and resulted in escalating human and economic losses. Among them, the earthquake is one of the major concerns of the various stakeholders related to urban planning. Originality/value In addition, the maximum time of discharge from the helter to the hospital has been 17 minutes, which means the presence of good access to selected shelters.
Article
Major accidents, like toxic gas releases, fires and explosions, may influence a large area. And thus, evacuation is a necessary public protection measure to mitigate the health consequences of major accidents, but risk assessment is still required. This paper focuses on providing an assessment framework of evacuation risk for major accidents, and the exposure dose calculated based on vulnerability model and accident probability is introduced to predict the risk. Evacuation risk evaluation based on “ALARP” guidelines is employed to partition the emergency planning area and to give suggestions for emergency preparation, as well as to classify the alternatives of evacuation flow assignment and find the optimal solution to decide whether to evacuate or to take shelter-in-place for emergency response through using different heuristics. The goal of its application in emergency response planning is to provide a fast heuristic method to select evacuation paths, but neither to minimize the evacuation time nor minimize the evacuation risk. The primary intention is to find an optimal solution within optimized evacuation time and with acceptable evacuation risk. A case study on evacuation risk assessment for phosgene leak accident in Yantai, China is used as an example to illustrate evacuation risk assessment process and its application in emergency preparation and response.
Article
Both pre-disaster approaches, e.g., mitigation and preparedness, and post-disaster approaches, e.g., response and recovery, play important roles to mitigate the damage from large-scale disasters. From the viewpoint of disaster response, there have been studies on evacuation guiding schemes and applications using evacuees’ mobile devices, e.g., smart phones. On the other hand, disaster preparedness has also been studied mainly on geographical information analysis, e.g., road blockage probability and people flow data. The road blockage probability is the probability that the corresponding road is blocked due to collapse of roadside buildings when an earthquake occurs. The people flow data express the people flow in usual time. In this paper, with the help of evacuation guiding schemes, road blockage probability, and people flow data, we propose a road network risk analysis approach that considers people flow in both ordinary and evacuation situations, which can be used to as a tool to strengthen the urban fabric for fostering better evacuees’ responses in disaster situations. First, the proposed approach derives ordinary road demand, which is the degree of road usage at a certain interval in an ordinary situation, from the people flow data. Then, it calculates evacuation road demand, i.e., the degree of road usage at a certain interval in an evacuation situation, by extending the edge betweenness centrality under the assumption that people located according to the ordinary road demand move to refuges along their evacuation paths. Finally, it detects roads with high risk of encountering blocked road segments by combining the road blockage probability and evacuation road demand. Through numerical experiments under a case study of Arako area of Nagoya city in Japan, we show the proposed approach can detect such high-risk roads. Furthermore, we show the detected roads spatially change according to the people flow in ordinary situations, evacuation behavior, and disaster occurrence time.
Article
Natural disasters have always existed as natural phenomena during the life of the planet. The occurrence of natural disasters such as earthquakes, floods, storms, etc. has often left destructive impacts on human settlements and has caused heavy casualties on its inhabitants and has imposed heavy economic and social burdens on human societies and countries of the world. . In view of the increasing population, especially in the Third World and developing countries, on the other hand, population density and settlement in old-fashioned and old-fashioned urban contexts and the emergence of problems caused by these issues, cities and cities in particular Babylon has been exposed to adverse effects and management abnormalities. Because the vacant areas have quickly become residential uses, the magnitude of the earthquake hazards has increased as a result. Therefore, the need to reduce the city's vulnerability to earthquakes has become one of the main goals of physical planning and urban planning. In this research, data and information were collected in both documents and field and analyzed in the ArcGIS software environment and after analyzing the risk and vulnerability of the region, it was examined whether the city of Babylon after the emergence of a The earthquake can have the least financial and fatal losses, and there are facilities and facilities available in the city that respond to the conditions of the crisis. Finally, some areas of Babylon were identified as having a high risk of earthquake, and solutions were presented for crisis management in these areas.
Chapter
With the rapid development of China’s economy, the number of industrial parks or projects involving hazardous chemicals is increasing annually. Currently, various major accidents, such as explosions, fires, chemical leaks, and unintentional poisoning frequently occurred due to human, equipment, production management, or environmental factors, and they might result in adverse effects on the health of those who work at chemical plants, as well as on the population in surrounding areas.
Article
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Coastal areas face a significant risk of tsunami after a nearby heavy earthquake. Comprehensive coastal port cities often complicate and intensify this risk due to the high vulnerability of their communities and liabilities associated with secondary damage. Accessibility to tsunami shelters is a key measure of adaptive capacity in response to tsunami risks and should therefore be enhanced. This study integrates the hazards that create risk into two dimensions: hazard-product risk and hazard-affected risk. Specifically, the hazard-product risk measures the hazard occurrence probability, intensity, duration, and extension in a system. The hazard-affected risk measures the extent to which the system is affected by the hazard occurrence. This enables the study of specific strategies for responding to each kind of risk to enhance accessibility to tsunami shelters. Nagoya city in Japan served as the case study: the city is one of the most advanced tsunami-resilient port cities in the world. The spatial distribution of the hazard-product risk and hazard-affected risk was first visualized in 165 school district samples, covering 213 km² using a hot spot analysis. The results suggest that the rules governing the distribution of these two-dimensional (2-D) risks are significantly different. By refining the tsunami evacuation time–space routes, traffic-location-related indicators, referring to three-scale traffic patterns with three-hierarchy traffic roads, are used as accessibility variables. Two-way multivariate analysis of variance (MANOVA) was used to analyse the differences in these accessibility variables to compare the 2-D risk. MANOVA was also used to assess the difference of accessibility between high-level risk and low-level risk in each risk dimension. The results show that tsunami shelter accessibility strategies, targeting hazard-product risk and hazard-affected risk, are significantly different in Nagoya. These different strategies are needed to adapt to the risk.
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Background: As phases of COVID-19 vaccination are quickly rolling out, how to evaluate the vaccination effects and then make safe reopening plans has become a prime concern for local governments and school officials. Methods: We develop a contact network agent-based model (CN-ABM) to simulate on-campus disease transmission scenarios at the micro-scale. The CN-ABM establishes a contact network for each agent based on their daily activity pattern, evaluates the agent's health status change in different activity environments, and then simulates the epidemic curve on campus. Based on the developed model, we identify how different community risk levels, teaching modalities, and vaccination rates would shape the epidemic curve. Results: The results show that in scenarios where vaccination is not available, restricting on-campus students to under 50% can largely flatten the epi curve (peak value < 2%); and the best result (peak value < 1%) can be achieved by limiting on-campus students to less than 25%. In scenarios where vaccination is available, it is suggested to maintain a maximum of 75% on-campus students and a vaccination rate of at least 45% to suppress the curve (peak value < 2%); and the best result (peak value < 1%) can be achieved at a vaccination rate of 65%. The study also derives the transmission chain of infectious agents, which can be used to identify high-risk activity environments. Conclusions: The developed CN-ABM model can be employed to evaluate the health outcome of COVID-19 outbreaks on campus based on different disease transmission scenarios. It can assist local government and school officials with developing proactive intervention strategies to safely reopen schools.
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This article examines the evacuation behavior of residents in two South Carolina communities, Hilton Head and Myrtle Beach, during the 1996 hurricane season. Two hurricanes that approached South Carolina but hit in North Carolina allowed us to study the impact of repeated “false alarms”; (evacuations ordered based on expectations of a hurricane landfall that proved to be wrong). Differences in evacuation behavior, specific information and concerns prompting evacuation, and the reliability of information sources between hurricane events are examined to determine the impact of false alarms on the credibility of warning systems. Data were derived from a face‐to‐face survey of residents 2 weeks after Hurricane Fran in September 1996. We found that the role of official advisories was more limited than reported in previous research as people sought information on more diverse sets of concerns in their decision making. Reliance on the media and the Weather Channel, in particular, for storm characteristics and advisories was an important factor in evacuation decision making during both hurricane events. The perceived lack of reliability of gubernatorial warnings coupled with dependence on the media suggests that residents find other sources of information more personally relevant. Thus, while residents do not find that officials are “crying wolf,”; they are searching elsewhere for information to assess their own risk—what does it mean to me if there is a wolf? This increased attention toward individual differences in perceived threat may become more pronounced in future evacuations from hurricanes.
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A survey of coastal South Carolina residents addressed the role of household decisions in amplifying demand on transporta-tion infrastructure during 1999's Hurricane Floyd evacuation. The evacuation rate averaged 65% 4.2% in coastal evacuation areas. Three major findings reveal that traffic problems are becoming a major consideration in whether people evacuate. How they evacuate is emerging as an issue for evacuation traffic planning. First, about 25% of households took two or more cars. Nearly 50% of evacuees left in one 6-h period. Major traffic pressure developed on the Interstate system, particularly Interstate-26. Second, while the majority of respondents carried road maps, only 51% of that group used them to determine their route. Many decided to stay on the Interstate despite the congestion. Finally, the majority of South Carolinian residents traveled distances greater than necessary for safe sheltering and more than in past hurricanes. Transportation issues will become more important in coastal evacuations as traffic problems impinge on peoples' ability to get out of harm's way and ultimately influence their decisions to evacuate.
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This study investigates the effectiveness of simultaneous and staged evacuation strategies using agent-based simulation. In the simultaneous strategy, all residents are informed to evacuate simultaneously, whereas in the staged evacuation strategy, residents in different zones are organized to evacuate in an order based on different sequences of the zones within the affected area. This study uses an agent-based technique to model traffic flows at the level of individual vehicles and investigates the collective behaviours of evacuating vehicles. We conducted simulations using a microscopic simulation system called Paramics on three types of road network structures under different population densities. The three types of road network structures include a grid road structure, a ring road structure, and a real road structure from the City of San Marcos, Texas. Default rules in Paramics were used for trip generation, destination choice, and route choice. Simulation results indicate that (1) there is no evacuation strategy that can be considered as the best strategy across different road network structures, and the performance of the strategies depends on both road network structure and population density; (2) if the population density in the affected area is high and the underlying road network structure is a grid structure, then a staged evacuation strategy that alternates non-adjacent zones in the affected area is effective in reducing the overall evacuation time.Journal of the Operational Research Society (2008) 59, 25–33. doi:10.1057/palgrave.jors.2602321 Published online 18 October 2006
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The advantages of agent-based modeling for a general theory of intelligence at the individual and social level are emphasized over other existing approaches mainly relying on rationality theories. As was pointed out during the National Academy of Sciences Sackler Colloquium session "Implications of Agent-Based Modeling for Understanding Human Rationality and Learning," held in October 2001, properties of social intelligent agents include adaptability and learning capacity, as well as the capacity to produce and employ artifacts and manipulate symbols.
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We consider a graph with n vertices, all pairs of which are connected by an edge; each edge is of given positive length. The following two basic problems are solved. Problem 1: construct the tree of minimal total length between the n vertices. (A tree is a graph with one and only one path between any two vertices.) Problem 2: find the path of minimal total length between two given vertices.
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This paper describes the development of a prototype spatial decision support system for use by emergency planners in developing contingency plans for evacuations from disaster areas. It links together a geographical information system (ARC/INFO) with a specially written object-oriented micro-simulator via a windowing computer operating system. The details of the system are described, its limitations are discussed and potential enhancements are identified.
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This study addresses group formation and leadership during the evaucuation of a high-rise office building due to fire. Rather than focussing on the psychological parameters of individual evacuee behaviour, the authors concentrate on the social context and organizational characteristics of the occupancy within which decisions about evacuation strategy, group formation and questions of leadership are made. A distinction is drawn between "emergent" (situational) and " imposed" (authoritative) leaders and between the processes of status emergence (achievement of influence) and status maintenance (retention of influence). Both leadership and group formation can be viewed not only in terms of psychological processes but also as the interaction between the normal organizational structure and the roles people assume and play within their group. Ce document porte sur la formation et le commandement de groupes lors de l'évacuation d'un édifice à bureaux de grande hauteur en cas d'incendie. Au lieu de faire porter leur attention sur les paramètres psychologiques du comportement individuel, les auteurs étudient le contexte social et les caractéristique organisationnelles de l'entité physique où se prennent les décisions concernant la stratégie d'évacuation, la formation de groupes et les questions de commandement. On fait une distinction entre les responsables et les leaders improvisés, et entre l'acquisition et le maintien de l'influence. Le commandement et la formation de groupes peuvent être considérés non seulement comme des processus psychologiques mais aussi comme l'expression d'une interaction entre la structure organisationnelle normale et les rôles que les personnes assument et jouent au sein de leur groupe. RES
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