A two-stage stochastic programming framework for transportation planning in disaster response

This study proposes a two-stage stochastic programming model to plan the transportation of vital first-aid commodities to disaster-affected areas during emergency response. A multi-commodity, multi-modal network flow formulation is developed to describe the flow of material over an urban transportation network. Since it is difficult to predict the timing and magnitude of any disaster and its impact on the urban system, resource mobilization is treated in a random manner, and the resource requirements are represented as random variables. Furthermore, uncertainty arising from the vulnerability of the transportation system leads to random-arc capacities and supply amounts. Randomness is represented by a finite sample of scenarios for capacity, supply and demand triplet. The two stages are defined with respect to information asymmetry, which discloses uncertainty during the progress of the response. The approach is validated by quantifying the expected value of perfect and stochastic information in problem instances generated out of actual data

Benefits of Managing the Capacity of Special Needs Shelters with Cross-County Collaboration

A significant task of planners involved in emergency disaster management is planning for the optimal assignment of people to emergency shelters. This complex task depends on the available infrastructure and roadway characteristics and can take on additional complexity when older populations are considered because their health conditions may deteriorate during a disaster. Older people may also require special assistance even though they are not listed in the registries of people with special needs. This paper specifically focuses on the assignment of older populations to shelters. The paper presents a spatial optimization methodology based on data from a geographic information system. The focus is on the segment of the population 85 years old and older and on the use of potential benefits of cross-county collaboration in special needs shelter (SpNS) management. Such collaboration can help in using additional shelter capacity between neighboring counties (a) to overcome the lack of capacity in a county and (b) to assign the demand to a close shelter across county borders. The methodology was applied to a case study of five counties in the Florida Panhandle. Because the SpNS demand for the 85+ age group was not known exactly, a sensitivity analysis was conducted for different demand levels. From an emergency management perspective, this type of cross-county utilization can provide a means to use existing regular shelters in multiple counties to serve the 85+ population