Using a neuromuscular training program may have a direct benefit in decreasing the number of anterior cruciate ligament injuries in female soccer players.

The Baca geothermal reservoir and adjacent aquifers in the Jemez Mountains of New Mexico comprise an integrated hydrogeologic system. Analysis of the geothermal reservoir either under natural conditions or subject to proposed development should account for the mass (water) and energy (heat) balances of adjacent aquifers as well as the reservoir itself. A three‐dimensional model based on finite difference approximations is applied to this integrated system. The model simulates heat transport associated with the flow of steam and water through an equivalent porous medium. The Baca geothermal reservoir is dominated by flow in fractures and distinct strata, but at the scale of application the equivalent porous media concept is appropriate. The geothermal reservoir and adjacent aquifers are simulated under both natural conditions and proposed production strategies. Simulation of natural conditions compares favorably with observed pressure, temperature, and thermal discharge data. The history matching simulations show that the results used for comparison are most sensitive to vertical permeability and the area of an assumed high‐permeability zone connecting the reservoir to a deep hydrothermal source. Simulations using proposed production strategies and optimistic estimates of certain hydrologic parameters and reservoir extent indicate that a 50‐MW power plant could be maintained for a period greater than 30 years. This production, however, will result in significant decreases in the total water discharge to the Jemez River.

Autonomous Vehicles (AVs), also known as self-driving cars, are a potentially transformative technology, but developing and demonstrating AV safety remains an open question. AVs offer some unique challenges that stretch the limits of traditional safety engineering practices. Most current safety standards and methodologies in the AV industry were not originally intended for application to autonomous vehicles, and they have significant limitations and shortcomings. In this article, we analyze the literature to first build an argument that a new safety framework is needed for AVs. We then use the identified limitations of current methodologies as a basis to formulate a set of fundamental requirements that must be met by any proposed AV safety framework. We propose a new AV safety framework based on the Hybrid Causal Logic (HCL) methodology, which combines Event Sequence Diagrams (ESDs), Fault Tree Analysis (FTA), and Bayesian Networks (BNs). The HCL framework is developed at a conceptual level and then evaluated versus the identified fundamental requirements. To further illustrate how the framework may meet the requirements, a simple example of an AV perception system scenario is developed using the HCL framework and evaluated. The results demonstrate that the HCL framework provides an integrated approach that has the potential to satisfy more completely the fundamental requirements than the current methodologies.

Volusia County, in east central Florida, comprises approximately 1,200 square miles situated between the St. Johns River and the Atlantic Ocean. Most of the County is underlain by a threeaquifer system. Population centers in Volusia County, which create a large water demand, are located near the coast. Saltwater intrusion into the ground water near these population centers has led to relocation of public water supply wells further inland. Regional management of the county's water resources commissioned construction of a three-dimensional computer model of the county. Predevelopment simulation results were used as initial conditions for the development simulations, which included well discharge data. The predevelopment model calibration consisted of reproducing field-determined potentiometric surfaces. As part of the calibration process, sensitivity analyses were performed on boundary conditions, recharge rates, permeability, and leakage properties. Results of the model study indicate the utility of computer models as a management tool for the complex ground-water system in Volusia County. (KEY TERMS: ground-water management; saltwater intrusion; finitedifference model.)

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