Number Of Evacuees Research Articles

Incorporating Household Gathering and Mode Decisions in Large‐Scale No‐Notice Evacuation Modeling

AbstractHousehold members tend to evacuate as a unit. However, most engineering‐based evacuation models treat evacuees as independent and separate entities, and overlook the interactions among household members during an evacuation (i.e., gathering children/spouses or uniting with other family members at home). The omission of these behaviors leads to imprecise modeling of evacuation situations. Additionally, transportation mode choice in a no‐notice evacuation has been seldom investigated. We present a framework to incorporate both household‐gathering behavior and mode choice in an emergency into an evacuation model to examine the effects of these two issues on evacuation efficiency and network performance. The framework was tested in the Chicago metropolitan region for two hypothetical incidents with evacuation radii 5 and 25 miles. Models that omit gathering behavior yield dangerously optimistic evacuation times and network congestion levels compared to models that include family interactions. These optimistic estimates are significant for a large‐scale evacuation—the reduction in the number of evacuees who can reach safe zones in a certain time threshold is nearly 50% between the gathering and no‐gathering models. Gathering behavior could also cause distinct effects on network performance for inner and outer areas, the break point of which may be where severe bottlenecks are located. In this study, average travel speed increases on the overall network within 15 miles of the incident location (where downtown Chicago is located), but decreases outside the 15‐mile radius. These results would be completely overlooked without incorporating the gathering behavior yet are critical for evacuation management.

Planning for Baseline Medical Care Needs of a Displaced Population After a Disaster

To build a tool to assist disaster response planning and estimate the numbers of displaced persons that will require special medical care during a disaster. We developed a tool, titled MedCon:PreEvent, which incorporates data from the 2006 National Health Interview Survey, 2005 National Hospital Discharge Survey, and 2004 National Nursing Home Survey to calculate numbers of emergency room/emergency department (ER/ED) visits, surgeries, health care home visits, overnight hospital stays, office visits, and self-rated health status. We then used thresholds of more than 12 office visits or 6 or more ER/ED visits or 6 or more surgeries or more than 4 home visits or more than 6 overnight hospital stays within the past 12 months to calculate rates per million evacuees requiring special medical care, including daily bed hospital and nursing home bed occupancy. We calculated that 79 428 (95% CI = 76 940-81 770) per million evacuees would need special medical care. The daily occupation of hospital beds would be 1710 beds (95% CI = 1328-2160) per million. The occupation of nursing home beds would be 5094 beds (95% CI = 5040-5148) per million. Changing the threshold to just those who self-rated health as "poor," the demand for special medical care would be 24 348 (95% CI = 23 087-25 535) per million. Using threshold utilization values at half the original level would increase the estimate to 226 988 (95% CI = 224 444-229 384) per million. A substantial number of persons with preexisting conditions will need suitable medical care following a disaster. The MedCon:PreEvent tool can assist disaster planners to prepare for medical care needs of large numbers of evacuees and consider re-evaluating the approach to utilizing and augmenting medical care services.

Multi-Objective Path Planning Model and Algorithm for Warship Evacuation

The aim of naval ship evacuation is to direct crewmembers form the dangerous cabins to mustering station or action station as quickly as possible, when the ship is likely to be attacked or on fire. While evacuating, the crew’s escape routes have to open various watertight doors or airtight doors, which will speed evacuation but it may also degrade the ship’s post-evacuation integrity. In the proposed the multi-objective path program model for warship emergency evacuation, in consideration of the conflict between the minimization of total travel time and the minimization of ship’s integrity. The multi-objective problem was converted into single objective problem by weighted method. The crew speed on each arc depends on the total number of evacuees traversing the arc at roughly the same time. We proposed a heuristic algorithm to solve the multi-objective time-varied escape route planning problem. Finally, a numerical example is presented to show the effectiveness and feasibility of this algorithm.

A Flow-Dependent Secondary-Shortest Path Algorithm for Naval Ship Evacuation

In this paper, we introduce a secondary evacuation planning problem which is solved by computing flow-dependent shortest path through a known shortest time escape route on a ship. Given a primary escape route, our secondary evacuation planning problem consists in finding the second-shortest escape route, based on the cabin network rebuilding. We suggest a new model for flow-dependent network where the travel time of each link depends on the flow speed and the flow speed depends on the total number of evacuees traversing the link. The model focused on the average evacuation time to travel through the ordered sequence of consecutive arcs by each group, and we proposed a heuristic algorithm to produce sub-optimal secondary evacuation plan. A numerical example is given at last. Results showing that our algorithm can effective supply the flow-dependent network k-shortest path need in reasonable computation times.

Reliable evacuation planning via demand inflation and supply deflation

This paper presents an evacuation route planning model that both accounts for demand uncertainty (i.e. the number of evacuees) as well as capacity uncertainty (i.e. the road capacities). To ensure reliability, the model plans for more evacuees (i.e. demand inflation) and less road capacity (i.e. supply deflation). A major contribution is that we provide a framework to determine the amount of demand inflation/supply deflation necessary to ensure a user-specified reliability level. The model is shown to be a natural generalization of previously proposed evacuation models. A small numerical case study reveals the key characteristics of the model.

EVACUATION ROUTE PLANNING: A CASE STUDY IN SEMANTIC COMPUTING

Semantic computing addresses the transformation of data, both structured and unstructured into information that is useful in application domains. One domain where semantic computing would be extremely effective is evacuation route planning, an area of critical importance in disaster emergency management and homeland defense preparation. Evacuation route planning, which identifies paths in a given transportation network to minimize the time needed to move vulnerable populations to safe destinations, is computationally challenging because the number of evacuees often far exceeds the capacity, i.e. the number of people that can move along the road segments in a unit time. A semantic computing framework would help further the design and development of effective tools in this domain, by providing a better understanding of the underlying data and its interactions with various design techniques. Traditional Linear Programming(LP) based methods using time expanded networks can take hours to days of computation for metropolitan sized problems. In this paper, we propose a new approach, namely a capacity constrained routing planner for evacuation route planning which models capacity as a time series and generalizes shortest path algorithms to incorporate capacity constraints. We describe the building blocks and discuss the implementation of the system. Analytical and experimental evaluations that compare the performance of the proposed system with existing route planners show that the capacity constrained route planner produces solutions that are comparable to those produced by LP based algorithms while significantly reducing the computational cost.

Management of Evacuee Surge from a Disaster Area: Solutions to Avoid Non-Emergent, Emergency Department Visits

Many emergency departments (EDs) in the United States experience daily overcrowding, and a rapid influx of evacuees fleeing a disaster area can pose a substantial burden. Some of these evacuees may require ED care. However, others lack an alternative to the ED to address non-emergent medical concerns (prescription refills or outpatient referral). The objective of this study was to describe a successful multidisciplinary Hurricane Katrina Evacuation Center, explain the services offered, and determine the center's effects on referrals to local EDs. Data were collected concerning the number of patients utilizing the medical evaluation center and compared to the total number of evacuees to determine the proportion that utilized medical care. The data concerning patients given prescriptions was obtained by the estimation of the two medical directors of the Center, and therefore, is inexact. During the five weeks the center was operational, 631 of 716 evacuees (88%) requested medical evaluation, and >80% of those had prescriptions written. Only four (<1%) patients were transported to local EDs. An evacuee evaluation center provides a convenient non-ED alternative for evacuees to address their non-emergent medical concerns and can be used to ease their transition to a new location.

Analysis of Evacuation Strategies for Design and Certification of Transport Airplanes

A method developed to assess the ine uence of the cabin arrangement in the emergency evacuation of transport airplanes is described. The method has been conceived for design and certie cation purposes and is not intended to reproduceaircraftaccidents.Theprocedureisbasedonaseat-to-exitassignmentalgorithmand asetofoperational restrictions and is aimed at minimizing the total distance traveled by all passengers along the escaping path and obtaining the most adequate sharing among the exits. Threerestrictions areconsidered: limitation in exit capacity, obligation to egress through the nearest exit, and limitation in the distance covered by each passenger. More than 30 cabins, belonging to turboprops, narrow-body, and wide-body jets, have been analyzed. Seat-to-exit distance of all passengers and number of evacuees per exit are the main output variables. A procedure to estimate differences inevacuation timeamong diverse conditions of thesame cabin, orbetween cabins of similarairplanes, is described. Theresultsshowtheine uenceoflefttorightasymmetriesandinappropriatematchingbetweensizeandlongitudinal location of exits.

The Great Flood of 1997 in Poland

The flood that occurred in summer 1997 in Poland, affecting the drainage basins of the Odra and the Vistula, caused 54 fatalities and material losses of the order of billions of US$. The flood struck a large part of the country and caused inundation of 665 000 ha of land. The number of evacuees was 162 thousand. The rhetoric commonly used in Poland refers to the Great Flood of 1997 as an event whose scale exceeded all imagination about the possible size of the disaster. Indeed, historic maxima of river stage and flow rate were considerably exceeded. From the hydrological point of view, this flood was a very rare event, with a return period in some river cross-sections of the order of a thousand years and more. As this natural disaster, striking a dynamically developing country-in-transition, attracted much international interest, a holistic view of it is presented. Attempts to answer the questions: “Could the disaster have been avoided?” and “What lessons can be learnt from the flood?” are also made.

Pharmaceutical services to evacuated U.S. military dependents

Pharmacy operations on Guam during Operation Fiery Vigil are recounted. In June 1991 Mount Pinatubo, a volcano near Clark Air Base in the Philippines, erupted and forced the evacuation of the base's population. Some 20,000 military dependents were transported to Guam. Those evacuees who needed medical attention--some 2500 of them--were escorted to a temporary medical unit located in and around Andersen Air Force Base and consisting of Army, Navy, and Air Force elements. Full-service health care, including 24-hour pharmaceutical services, was available. A central pharmacy and four satellite pharmacies were established. The four-man pharmacy staff went on 12-hour shifts and made frequent trips to all the medical sites. The pharmacy established and maintained drug stocks and supplies and provided drug information, particularly information on therapeutic equivalents. Constant readiness for emergency drug requests was maintained, and the pharmacy was responsible for transporting drugs. The pharmacy also supported the Army Veterinary Service in processing, quarantining, and caring for 1300 pets. Cold, motion sickness, and sunburn preparations and analgesics accounted for more than half the prescriptions filled. Problems included the sheer number of evacuees, language barriers, the difference in formularies used by the pharmacies in the Philippines and Guam, and the physical and psychological stress to which the evacuees were subjected. Teamwork and coordination among the three U.S. military branches made it possible to satisfy the enormous medical and pharmaceutical needs of dependents evacuated from the Philippines after Mount Pinatubo erupted.

ACTION RESEARCH ON EVACUATION METHOD IN EMERGENT SITUATION (II)

Two evacuation methods in emergent situation were compared in a field experiment. One was a traditional method, named “Follow-direction method”, in which each leader indicated an exit for evacuees with loud voice and large gesture, while moving himself toward the exit. The other was a new method, named “Follow-me method”, in which each leader acted one on evacuee to follow him and actually proceeded to the exit without calling out to many evacuees nor indicating the direction of the exit.The experiment focused on effects of a leader: evacuee ratio on the efficiency of these two methods. Both leaders and evacuees were university students, but leaders had been trained in their assigned method. Five conditions were introduced; (1) four leaders using Follow-direction method, (2) four leaders using Follow-me method, (3) two leaders using Follow-direction method, (4) two leaders using Follow-me method, and (5) two leaders, one using Follow-direction method and the other using Follow-me method. The number of evacuees was sixteen, fourteen males and two females, in each condition. At the beginning of evacuation, two exits were opened. One was close to and visible for evacuees, and the other was invisible from initial evacuee positions. Each leader, however, evacuated through the latter exit.Leader: evacuee ratio was found to determine the effectiveness of the Follow-me method. When leader: evacuee ratio was 1: 4 (four leader condition), the Follow-me method achieved more rapid evacuation than the Follow-direction method as in the study of Sugiman, Misumi, and Sako (1983). Contrary, when leader: evacuee ratio was 1: 8 (two leader condition), eleven evacuees left through the exit to which leaders did not lead in the two leader Follow-me method. It was only in the two leader Follow-me method that evacuees appeared who used a wrong exit. Furthermore, the two leader mixed method achieved more rapid evacuation than the two leader Follow-direction method. This was considered to provide a basis for using Followdirection and Follow-me methods jointly in real evacuation planning.

British Food Journal Volume 54 Issue 3 1952

British Food Journal Volume 54 Issue 3 1952