Facility location under demand uncertainty: Response to a large-scale bio-terror attack

In the event of a catastrophic bio-terror attack, major urban centers need to efficiently distribute large amounts of medicine to the population. In this paper, we consider a facility location problem to determine the points in a large city where medicine should be handed out to the population. We consider locating capacitated facilities in order to maximize coverage, taking into account a distance-dependent coverage function and demand uncertainty. We formulate a special case of the maximal covering location problem (MCLP) with a loss function, to account for the distance-sensitive demand, and chance-constraints to address the demand uncertainty. This model decides the locations to open, and the supplies and demand assigned to each location. We solve this problem with a locate-allocate heuristic. We illustrate the use of the model by solving a case study of locating facilities to address a large-scale emergency of a hypothetical anthrax attack in Los Angeles County.     

Knowledge,attitudes, and practices of family physicians and nurses regarding unintentional injuries among children under 15 years in Cairo,Egypt

Unintentional injuries are a leading cause of death among children, especially in developing countries. Lack of reliable data regarding primary health care professionals' role in childhood unintentional injury prevention hinders the development of effective prevention strategies. A survey of 99 family physicians and nurses from 10 family health centres sought to develop insight into their knowledge, attitudes, and practices regarding unintentional injury prevention for children <15 in Cairo, Egypt. Approximately, 60% were familiar with the terms unintentional injuries and injury prevention. Falls and road traffic crashes were identified as primary causes of childhood injuries by 54.5%. While >90% agreed injury prevention counselling (IPC) could be effective, only 50.5% provided IPC. Lack of time and educational materials were the leading barriers to provision of IPC (91.9% and 85.9%, respectively), while thinking counselling is not part of their clinical duties was the least perceived barrier (9.1%). There is a large disconnect between providers' knowledge, attitudes and practices regarding IPC, more training and provision of counselling tools are essential for improving IPC by Egyptian medical providers.     

A delay estimation technique for single and double-track railroads

To route and schedule trains over a large complex network can be computationally intensive. One way to reduce complexity could be to “aggregate” suitable sections of a network. In this paper, we present a simulation-based technique to generate delay estimates over track segments as a function of traffic conditions, as well as network topology. We test our technique by comparing the delay estimates obtained for a network in Los Angeles with the delays obtained from the simulation model developed by Lu et al. [Lu, Q., Dessouky, M.M., Leachman, R.C., 2004. Modeling of train movements through complex networks. ACM Transactions on Modeling and Computer Simulation 14, 48–75], which has been shown to be representative of the real-world delay values. Railway dispatchers could route and schedule freight trains over large networks by using our technique to estimate delay across aggregated network sections.