To the Rescue: Optimally Locating Trauma Hospitals and Helicopters

Injury (trauma) is the leading cause of death in the United States for people younger than 45 years of age. Each day, more than 170,000 men, women, and children are injured severely enough to seek medical care. About 400 of these people will die and another 200 will sustain a long-term disability as a result of their injuries. An estimated 20-40% of trauma-related deaths could be prevented if all Americans lived in communities that were served by a well-organized system of trauma care. This Issue Brief describes a new computer model that can help State and regional policymakers decide where to place designated trauma hospitals and helicopter depots to maximize their residents’ access to trauma care

OpenET : filling a critical data gap in water management for the western United States.

The lack of consistent, accurate information on evapotranspiration (ET) and consumptive use of water by irrigated agriculture is one of the most important data gaps for water managers in the western United States (U.S.) and other arid agricultural regions globally. The ability to easily access information on ET is central to improving water budgets across the West, advancing the use of data-driven irrigation management strategies, and expanding incentive-driven conservation programs. Recent advances in remote sensing of ET have led to the development of multiple approaches for field-scale ET mapping that have been used for local and regional water resource management applications by U.S. state and federal agencies. The OpenET project is a community-driven effort that is building upon these advances to develop an operational system for generating and distributing ET data at a field scale using an ensemble of six well-established satellite-based approaches for mapping ET. Key objectives of OpenET include: Increasing access to remotely sensed ET data through a web-based data explorer and data services; supporting the use of ET data for a range of water resource management applications; and development of use cases and training resources for agricultural producers and water resource managers. Here we describe the OpenET framework, including the models used in the ensemble, the satellite, meteorological, and ancillary data inputs to the system, and the OpenET data visualization and access tools. We also summarize an extensive intercomparison and accuracy assessment conducted using ground measurements of ET from 139 flux tower sites instrumented with open path eddy covariance systems. Results calculated for 24 cropland sites from Phase I of the intercomparison and accuracy assessment demonstrate strong agreement between the satellite-driven ET models and the flux tower ET data. For the six models that have been evaluated to date (ALEXI/DisALEXI, eeMETRIC, geeSEBAL, PT-JPL, SIMS, and SSEBop) and the ensemble mean, the weighted average mean absolute error (MAE) values across all sites range from 13.6 to 21.6 mm/month at a monthly timestep, and 0.74 to 1.07 mm/day at a daily timestep. At seasonal time scales, for all but one of the models the weighted mean total ET is within ±8% of both the ensemble mean and the weighted mean total ET calculated from the flux tower data. Overall, the ensemble mean performs as well as any individual model across nearly all accuracy statistics for croplands, though some individual models may perform better for specific sites and regions. We conclude with three brief use cases to illustrate current applications and benefits of increased access to ET data, and discuss key lessons learned from the development of OpenET

Cost-Efficient Reserve Site Selection Favoring Persistence of Threatened and Endangered Species

This article formulates and tests set covering and related models with spatial characteristics for selecting sites that provide habitat for species that are identified as “critical” (e.g., typically threatened, endangered, or rare), thereby enhancing their persistence. The first two models presented require the creation of a core area for each critical species and a buffer zone surrounding the core, with and without being constrained to include at least one representation of each and every common (i.e., noncritical) species. The final model aims at minimizing costs of protecting predetermined numbers of common species while all critical species remain covered and buffered. These models are implemented for occurrence data of terrestrial mammals in Oregon. They enable, among other things, a comparison between the budgetary impacts of reserve networks with and without buffering rings for critical species, and a determination of the marginal cost of common species protection.Este estudio formula y evalúa modelos de cubrimiento total o ‘set covering’ y otros modelos similares que utilizan características espaciales para hallar soluciones que identifican áreas de hábitat para especies consideradas como ‘críticas’ (por ejemplo, amenazadas o en peligro de extinción) con el fin de promover su conservación. Los dos primeros modelos requieren la creación de un área núcleo para cada especie ‘crítica’ así como una zona de amortiguamiento que la rodea. Estas áreas pueden o no tener como restricción la representación de cada una y todas las especies comunes (o ‘no críticas’). El modelo final busca minimizar los costos de proteger cantidades predeterminadas de especies comunes y al mismo tiempo asegurar la protección de especies ‘críticas’ en áreas núcleo y de amortiguamiento. Los modelos son implementados utilizando datos de presencia de mamíferos terrestres en el estado de Oregon (EEUU). Los métodos presentados aquí permiten, entre otras cosas, comparar los costos de áreas y redes de conservación con o sin amortiguamiento de especies “críticas”, y el cálculo del costo marginal de la protección de especies más comunes

Biological Reserves, Rare Species and the Tradeoff Between Species Abundance and Species Diversity

The preservation of species diversity generally suggests protection of either the greatest number of species possible or all species. Requiring representation of each species in at least one parcel in the system and seeking the minimum number of parcels in the reserve system to achieve this requirement is termed the Species Set Covering Problem (SSCP). Nonetheless, it is important, as well, to consider the rarest of species, as their populations are the most in need of protection to assure their survival. This paper uses 0–1 programming models and an existing data set to study species protection, rarity, species abundance and species diversity. We employ for this purpose an integer programming model that uses the SSCP format to require at least one representation of each and every species, but that seeks in addition protection of the rarest species. This is achieved by maximizing redundant coverage of those species designated as rare. Results are then compared to those of the SSCP. Recognizing that resources available for conservation purchases could well be insufficient to represent all species at least once, we structure a model comparing coverage of the greatest number of species and redundant coverage of rare species. We develop a trade-off curve for this multi-objective problem in order to evaluate the opportunity cost of covering more species as redundant coverage of rare species decreases—and vice versa. Finally, various possible rarity sets and various budget proxies are considered along with their impacts on conservation policies, Pareto optimality and species diversity

Civil and Environmental Systems Engineering

X, 507 tr.; 24 cm