Evacuation Risk Research Articles

Modeling emergency evacuation with time and resource constraints: A case study from Gujarat

This study develops an off-site emergency response plan for a nuclear power plant in Gujarat, India subject to time constraints with resource limitations and risk of radiation exposure to victims. We formulate an optimization model to capture the effect of delay in evacuation, limited resource availability, and costs associated with resource allocation. A single chain closed queuing network model with class switching is used to model traffic congestion during evacuation. The throughput measures from the queuing network are used as inputs in the optimization model. Further, two resource allocation strategies are suggested and genetic algorithm is used for optimizing resource utilization and evacuation risk. The results indicate that pooling resources among a cluster of affected areas is most suitable for evacuation. Numerical experiments are conducted to analyze the time trade-offs and the effect of service time variability on the expected evacuation time. The proposed model can serve as an important resource planning and allocation tool for emergency evacuation.

Analysis of dynamic road risk for pedestrian evacuation

Knowing the dynamic road risk for pedestrian evacuation and having an efficient evacuation plan play a very important role in the serious disasters such as earthquake, tsunami and hurricane. In this paper, the dynamic road risk for pedestrian evacuation in a densely populated area of Beijing was studied with consideration of different influencing factors. Firstly, the eight influencing factors including road width, node degree, safety betweenness, road resistor coefficient, building threat, pedestrian counterflow, illegal vehicle parking and traffic flow were considered to assess the road risk for pedestrian evacuation. Secondly, based on complex network theory, electric circuit theory and real situation of the roads, the comprehensive assessment function for road risk was developed quantitatively based on the eight influencing factors. Thirdly, we analyzed road risk for pedestrian evacuation considering different situations: current condition, regular condition, and optimal condition; the risk distribution maps were drawn to directly show the risk level. Through assessments, the roads with high risk for pedestrian evacuation were found, and an optimized evacuation plan was obtained and analyzed. This mathematical model can guide the emergency evacuation in real time. The process and the results are essential for improving the efficiency of evacuations which should considerably reduce the possibility of injuries, deaths and other losses in the disaster.

Risk Factors for Mental Health Aeromedical Evacuation Among German Armed Forces Soldiers Deployed to Afghanistan

Due to deployment-related stress, a considerable number of soldiers have to be evacuated from theater. Medical reports of all soldiers who were evacuated for mental health reasons during the 22nd German ISAF Contingent ( N = 35) were evaluated with regard to sociodemographic and operational factors. Data were compared with a questionnaire survey of the same contingent ( N = 1,165). Logistic regression showed a significantly higher risk of evacuation for soldiers who had participated in combat (Exp. B: 7.9; p = .002), those who had been stationed in Kunduz (Exp. B: 4.1; p = .005), and soldiers under the age of 26 (Exp. B: 4.0; p = .013).These pilot study data can help identify target groups for more comprehensive measures of stress prevention.

Introduction of Disaster Cognitive Psychological Science

Disaster science is an academic field that explores mechanisms of disasters, investigates economic, social, and environmental impact of disasters, and develops systems for disaster prevention, mitigation, and restoration. After the 2011 Great East Japan (Tohoku) earthquake and tsunami disaster, reduction and avoidance of potential losses from disasters have received much attention. The purpose of this article is to introduce a new research field in disaster science called disaster cognitive psychological science. First, we define disasters in disaster science. Second, disaster cognitive psychological science is introduced. The scopes of disaster cognitive psychological science are 1) to clarify human mental processes and behaviors in any situation related to disasters such as evacuation behavior, risk perception, and decision making, and 2) to develop and evaluate new systems for disaster prevention, mitigation, and restoration such as education and training programs for disaster prevention. Finally, disaster cognitive psychological science research has only just begun. We shall continue our research related to disaster cognitive psychological science.

Tsunami Safe Town Planning with Evacuation Simulation

Tsunami evacuation plans have been deliberately developed by local governments in coastal areas in Japan under guidance from the national government since before the Great East Japan Earthquake in March 2011. These plans, however, do not mention the time required for all local residents to evacuate to evacuation areas. This paper reports a procedure to design an effective tsunami safe town planning using multi-agent simulator (MAS) which identify a degree of evacuation risk in objective area. A case study is applied to one of the worst hit town of tsunami, in which additional facilities such as evacuation areas, safe buildings, and evacuation routes are proposed as well.

Mirizzi Syndrome in Gallstone Complication

Mirizzi syndrome is a rare complication of gallstone which is characterized by the presence of gallstone impaction in cystic duct that leads to inflammatory stricture in the biliary duct and results in obstructive jaundice. In this report, we highlighted the diagnostic approach and management of Mirizzi syndrome in a 58 year-old male complaining of nausea, vomiting, and appearing jaundice. The role of imaging such as abdominal ultrasonography in depicting the characteristics of Mirizzi syndrome was also discussed and compared the findings with the classification of the disease in the literature. In this patient, Mirizzi syndrome was suspected by the appearance acoustic shadow in the gallbladder with dilated cystic duct suggesting the impaction of common bile duct (CBD). We performed endoscopic retrograde cholangiopancreatography (ERCP) as both diagnostic and therapeutic modalities by which we allowed sphingterectomy to evacuate the gallstone. However, due to the risk of further stone evacuation, the procedure was followed by elective cholecystectomy. Keywords: gallstone, Mirizzi syndrome, complication

Design Concept for Evacuation Warning System of Elevator in Fire

This paper presents the input and output of elevator evacuation warning system based on the analysis of elevator evacuation risk in fire, and expounds elevator evacuation warning system design concept from three aspects, which are "use of the elevator is safe", " waiting for the elevator is safe" and "elevator's decision is a safe choice".

The association between actual and perceived flood risk and evacuation from Hurricane Irene, Beaufort County, North Carolina

AbstractHurricane evacuation orders are often issued by local governments for individuals living in flood‐prone areas, but adherence to these orders is dependent on many factors, including an accurate perception of risk. One month after Hurricane Irene made landfall, interviews were conducted with 205 households in Beaufort County, NC, to assess the association between perceived and actual risk of flooding and evacuation. Crude and adjusted prevalence differences were calculated among households within areas of known flood risk. Households in the 100‐ and 500‐year flood plain were more likely to evacuate than those in non‐flood areas prior to Hurricane Irene, but perceived risk was not associated with evacuation, even after adjustment. Perceptions of flood risk did not align with actual risk of flooding in the majority of respondents. Actual flood risk is an important environmental cue in the construction of risk perception and in the decision to evacuate prior to hurricanes.

선박 구조 개선을 통한 승무원의 피난 효율 향상을 위한 연구

Abstract : Onshore great fires can normally be extinguished by firefighters using special firefighting equipment and its suitable method. However, offshore fires on the ships are to be extinguished by the crew without any supports from the onshore. Also, crews working on board are exposed to high risk of emergency evacuation due to the complicated structure arrangement of the ships and different accident types such as fire and ship collisions. As most of damage and loss of life in fire are associated with suffocation, shortening of evacuation time is an important factor to improve a survival rate. In this study, visibility in the accommodation area is analyzed by using the temperature and smoke flow which are obtained by the Fire Dynamic Simulator(FDS) as a Three-Dimensional Fire Analysis program to understand the survival rate of the crew upon the fire. The fire doors for most of ships are designed to close automatically when the fire alarm is activated. These auto-matic closing of the fire doors is a very effective system to delay the spread of flame and smoke flow for the unmanned spaces of the fire protected area. However, if the crew cannot escape within the estimated

Risk-based spatial zone determination problem for stage-based evacuation operations

This study seeks to determine risk-based evacuation subzones for stage-based evacuation operations in a region threatened/affected by a disaster so that information-based evacuation strategies can be implemented in real-time for the subzone currently with highest evacuation risk to achieve some system-level performance objectives. Labeled the evacuation risk zone (ERZ), this subzone encompasses the spatial locations containing the population with highest evacuation risk which is a measure based on whether the population at a location can be safely evacuated before the disaster impacts it. The ERZ for a stage is calculated based on the evolving disaster characteristics, traffic demand pattern, and network supply conditions over the region in real-time subject to the resource limitations (personnel, equipment, etc.) of the disaster response operators related to implementing the evacuation strategies. Thereby, the estimated time-dependent lead time to disaster impact at a location and the estimated time-dependent clearance time based on evolving traffic conditions are used to compute evacuation risk. This time-unit measure of evacuation risk enables the ERZ concept to be seamlessly applied to different types of disasters, providing a generalized framework for mass evacuation operations in relation to disaster characteristics. Numerical experiments conducted to analyze the performance of the ERZ-based paradigm highlight its benefits in terms of better adapting to the dynamics of disaster impact and ensuring a certain level of operational performance effectiveness benchmarked against the idealized system optimal traffic pattern for the evacuation operation, while efficiently utilizing available disaster response resources.

Multiple Ileal Perforations Following Dilatation and Evacuation for Missed Abortion

Sir, Miscarriage has traditionally been treated by surgical evacuation, on the assumption that any retained tissue increases the risk of infection and haemorrhage. One of the serious risks of surgical evacuation is uterine perforation (upto 5 in 1,000 women) [1]. Over the last decade, the management of abortion has become medical to reduce the life threatening complications associated with surgical techniques. But still medical management is not being followed by every practising obstetrician or surgeon. A 25-year-old married lady presented to our hospital with fever, abdominal pain and vomiting for two days following dilatation and evacuation for missed abortion at eight weeks of gestation at a private hospital. Abdomen was tender and guarding was present. On laparotomy, there was a 5mm perforation on the anterior wall of the uterus near the fundus [Table/Fig-1] and multiple (6) ilealperforations measuring 0.5-1cm each [Table/Fig-2]. [Table/Fig-1]: 5mm perforation on the anterior wall of the uterus near the fundus on laparotomy [Table/Fig-2]: Multiple (6) ilealperforations measuring 0.5-1cm each on laparotomy Uterine perforation was freshened and approximated with vicryl. Segmental resection and anastomosis of 8 cm of the ileum was performed. Post-operatively she had febrile spikes which subsided on the 4th day; peritoneal fluid aspirate culture showed E.Coli which resolved with appropriate antibiotics. On 10th day post-operation, she was discharged home. She continued to have pain in the abdomen which was managed as acid peptic disease on outpatient basis. She required admission once when she presented to casualty 46 days after discharge from hospital with upper abdominal pain and vomiting and a provisional diagnosis of adhesive intestinal obstruction was made. Her symptoms subsided with conservative treatment. The present day treatment of abortion is medical management [2]. Surgery has a limited role. The aim of the surgical procedure should be to treat an incomplete or missed miscarriage, or retained placental tissue not responsive to timely medical management.

Principal Aspects Regarding to the Emergency Evacuation of Large-scale Crowds: A Brief Review of Literatures Until 2010

As a kind of emergency evacuation, the large-scale evacuation is an effective measure to mitigate disaster in a sudden crises. Research into the emergency evacuation of crowds has been the focus of many scholars at home and abroad for some time. In this paper, four principal aspects of current research into large-scale crowd evacuation, namely evacuation theories, evacuation modeling, evacuation decision-making and evacuation risk evaluation have been summarized. Of these, evacuation modeling has attracted the greatest interest. While some evacuation models have proved effective tools in evacuation decision-making and risk evaluation, existing evacuation models have not fully considered the uncertain factors in the process of large-scale evacuation.

CFD기반 화재 대피 시뮬레이션 모델을 적용한 위험도 평가 분석 -인천터미널역 역사를 대상으로

최근 실내 공간에서의 재난, 화재와 테러 등 대피상황을 재현하여 이를 가시화하기 위한 연구가 주목 받고 있으며, 실내 공간에 대한 모델을 설계하고 인명 안전 평가를 통한 신뢰성 있는 분석이 요구되고 있다. 이에 본 연구에서는 실제적인 건물 화재 위험 요인을 고려하여 피난 안전성 분석과 피난 경로 안내가 가능한 시뮬레이션 모델을 개발하고자 하였다. 이를 위해 인천터미널역 역사를 대상으로 3차원 화재 및 피난 모델을 설계하고, 실내 내장재의 재질을 바탕으로 열 매개변수와 화재 인지 장치를 이용하여 화재 위험 분석을 수행하였다. 둘째, 인명안전을 위한 평가에 있어 화재 시뮬레이션인 FDS(Fire Dynamics Simulator)와 피난 시뮬레이션을 통해 재실자가 인체에 손상 없이 견딜 수 있는 피난허용시간(ASET: Available Safe Egress Time)을 산출하였다. 또한 화재를 감지하고 안전한 장소까지 완전하게 피난하는데 소요되는 피난요구시간(RSET: Required Safe Egress Time)을 계산하고 이를 비교 분석하였다. 결과적으로 연구대상의 3차원 공간적인 정보를 기반으로 한 실내 공간 모델과, 고시된 안전기준을 반영한 열차 내 화재 및 피난 위험도 측정 시뮬레이션 분석을 통해 보다 실제적인 안전성 평가를 수행 할 수 있었다. Recently, the research to visualize and to reproduce evacuation situations such as terrorism, the disaster and fire indoor space has been come into the spotlight and designing a model for interior space and reliable analysis through safety evaluation of the life is required. Therefore, this paper aims to develop simulation model which is able to suggest evacuation route guidance and safety analysis by considering the major risk factor of fire in actual building. First of all, we designed 3D-based fire and evacuation model at a subway station building in Incheon and performed fire risk analysis through thermal parameters on the basis of interior materials supplied by Incheon Transit Corporation. In order to evaluate safety of a life, ASET (Available Safe Egress Time), which is the time for occupants to endure without damage, and RSET (Required Safe Egress Time) are calculated through evacuation simulation by Fire Dynamics Simulator. Finally, we can come to the conclusion that a more realistic safety assessment is carried out through indoor space model based on 3-dimension building information and simulation analysis applied by safety guideline for measurement of fire and evacuation risk.

창원시 재해위험지구 대피 적합성 분석

본 연구에서는 과거 태풍 루사와 매미로 침수피해가 발생해 재해위험지구로 지정된 창원시 마산합포구 신포지구와 해운지구를 연구대상지로 선정하여 대피자 특성에 따른 대피소의 접근성을 분석하였다. 대피속도는 신체조건을 고려하여 어린이, 일반성인, 노약자로 구분하여 분석하였다. 해운지구의 경우 현재 지정된 대피소가 적절한 것으로 분석되었으나 신포지구에서 노약자의 경우 재해위험지구의 50%이상이 대피 취약지역으로 나타났다. 따라서 추가적으로 3개의 대피소가 지정되었고, 그 결과 기존의 대피소에서 발생되었던 대피취약지역이 개선되었음을 알 수 있었다. 본 연구에서 얻어진 결과는 대피 위험도와 문제점을 해결하기 위한 보완 대책을 수립하는데 이용될 것으로 판단된다.

Calculation of Evacuation Risk in Fire by Type of Building Use Based on Statistical Data - Study on Criteria of Design Evacuation Risk for Fire Safety Design of Buildings -

Calculation of Evacuation Risk in Fire by Type of Building Use Based on Statistical Data - Study on Criteria of Design Evacuation Risk for Fire Safety Design of Buildings -

Clearance Time Estimation for Incorporating Evacuation Risk in Routing Strategies for Evacuation Operations

This study seeks to develop an approximate but efficient approach for estimating evacuation clearance time which is defined as the time required to evacuate the population of a location to areas of safety. Elsewhere, this estimate of the clearance time is used as input to infer evacuation risk for a location which reflects whether the population of that location can be safely evacuated before the disaster impacts it. As the computed evacuation risk is used in a real-time stage-based framework for evacuation operations, the approach for clearance time estimation needs to be computationally efficient while being capable of approximating traffic flow dynamics reasonably. To address these needs, a dynamic routing policy labeled the location-priority routing is proposed, and the associated clearance time estimation problem is formulated as a dynamic network flow problem. The location-priority is based on the lead time that a location has until it is impacted by the disaster, and designates that the population at a location with a shorter lead time has higher priority in using roadway capacity for evacuation. By combining the location-priority routing with the consideration of a super sink, the routing problem for the evacuation network is transformed into sequential single-origin single-destination dynamic routing problems. It avoids expensive iterative search processes, enabling computational efficiency for real-time evacuation operations. The solution approach approximately captures the evolution of traffic dynamics across the stages of the operational framework. Results from numerical experiments illustrate that the proposed approach can address the aforementioned needs related to clearance time estimation.

Simulation Evacuation Modeling of A Commercial Shopping District to Safe Zones

Commercial shopping districts offer challenges for emergency planners to plan for the evacuation of short-notice emergency events. This paper illustrates a simulation analysis of the evacuation a large commercial shopping district, which focuses on street and parking lot vehicle traffic. Microscopic simulation is used to track the behaviors of vehicles evacuating from parking lots to safe zones. Evacuation scenarios investigate evacuation strategies by varying factors involving the occupancy rate of parking lots, inbound traffic control, and destination assignment policy. The performance of the evacuating vehicles is measured by an evacuation risk profile including the most problematic parking lots in terms of evacuation time. A trade-off analysis illustrates the effectiveness of the evacuation strategies in terms of costs, time, and risk. The simulation results indicate that an optimized destination assignment policy can alleviate traffic congestion and reduce total evacuation time.

The need for repeat evacuation of retained products of conception: How common is it?

Evacuation of retained products of conception with suction curettage is a widely used method for the management of missed miscarriage, incomplete miscarriage and termination of pregnancy. This procedure carries a risk of incomplete evacuation, which may lead to a further repeat evacuation. There are limited data on the incidence of repeat evacuation for suspected retained products. We undertook a retrospective audit on patients who underwent suction curettage for retained products of conception between January 2006 and February 2008, in order to evaluate the rate of repeat evacuation. Our study showed 3.1% (17 of 541) of patients underwent a repeat evacuation for suspected retained products. Suction curettage remains a safe and common procedure, however, it is important to minimise the recurrence of repeat evacuations through the use of medical management, improved training and local guidelines. This in turn should lower the risk of further complications associated with a surgical procedure.

Risk of Large‐Scale Evacuation Based on the Effectiveness of Rescue Strategies Under Different Crowd Densities

Crowd density is a key factor that influences the moving characteristics of a large group of people during a large-scale evacuation. In this article, the macro features of crowd flow and subsequent rescue strategies were considered, and a series of characteristic crowd densities that affect large-scale people movement, as well as the maximum bearing density when the crowd is extremely congested, were analyzed. On the basis of characteristic crowd densities, the queuing theory was applied to simulate crowd movement. Accordingly, the moving characteristics of the crowd and the effects of typical crowd density-which is viewed as the representation of the crowd's arrival intensity in front of the evacuation passageways-on rescue strategies was studied. Furthermore, a "risk axle of crowd density" is proposed to determine the efficiency of rescue strategies in a large-scale evacuation, i.e., whether the rescue strategies are able to effectively maintain or improve evacuation efficiency. Finally, through some rational hypotheses for the value of evacuation risk, a three-dimensional distribution of the evacuation risk is established to illustrate the risk axle of crowd density. This work aims to make some macro, but original, analysis on the risk of large-scale crowd evacuation from the perspective of the efficiency of rescue strategies.

Country Factors Associated With the Risk of Hospitalization and Aeromedical Evacuation Among Expatriate Workers

To assess country factors associated with the risk of requiring aeromedical evacuation and hospitalization among expatriate workers and their dependents. The 2009-2010 data including 5725 aeromedical evacuations and 17,828 hospitalizations, and 2009 data of hospitalizations and aeromedical evacuations among 94,651 at-risk expatriates, were analyzed to assess 2 country risk rating tools. Each tool utilized four risk categories and reflected level of development and medical capabilities. Country risk category was strongly associated with risk of evacuation and/or hospitalization for each risk rating tool (eg, 46-fold increase from lowest to highest country risk category). Country risk tools strongly associate hospitalization and aeromedical evacuation with country risk category, and thus can be important indicators of relative medical risk. Employers may use these results to implement targeted prevention programs to support expatriate workers and their families.