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1. Wave-by-Wave Control of a Wave Energy Converter with Deterministic Wave Prediction

   Korde, Umesh A. (September 2017, European Wave and Tidal Energy Conference)

   This paper discusses wave-by-wave near-optimal control of a wave energy device in irregular waves. A deterministic propagation model is used to predict the wave elevation several seconds into the future at the device location. Two prediction approaches are considered. The first is based on a time series being measured over an advancing time window at a particular up-wave location. This approach is here utilized in long-crested irregular waves. The second approach uses successive snapshots of wave elevation measurements over an up-wave area. This approach is found more convenient for multi-directional waves, and is here applied in a bi-directional wave irregular wave field. A small, heaving vertical cylinder reacting against a deeply submerged (i.e. assumed to undergo negligible oscillations) mass is studied under wave-by-wave control. The non-causal feedforward control force required for optimum velocity under a swept-volume constraint is based on the past, current, and predicted wave elevation at the device. Results for time-averaged converted power and displacement/force maxima are obtained for a range of irregular wave conditions. Also presented in addition are energy conversion results with a feedback-alone control force using a multi-resonant control technique. 

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2. A Numerical Scheme for Wave Turbulence: 3-Wave Kinetic Equations

   https://doi.org/10.1137/22M1492210  

   Walton, Steven; Tran, Minh-Binh (August 2023, SIAM Journal on Scientific Computing)
3. Plane wave elastography: a frequency-domain ultrasound shear wave elastography approach

   https://doi.org/10.1088/1361-6560/ac01b8  

   Khodayi-mehr, Reza; Urban, Matthew W; Zavlanos, Michael M; Aquino, Wilkins (June 2021, Physics in Medicine & Biology)

   null (Ed.)
4. Policies for a Second Wave

   Baqaee, D.; Farhi, E.; Mina, M.; Stock, J. (July 2020, Brookings papers on economic activity)

   Eberly, Jan; Romer, David (Ed.)

   In the spring of 2020, the initial surge of COVID-19 infections and deaths was flattened using a combination of economic shutdowns and noneconomic non-pharmaceutical interventions (NPIs). The possibility of a second wave of infections and deaths raises the question of what interventions can be used to significantly reduce deaths while supporting, not preventing, economic recovery. We use a five-age epidemiological model combined with sixty-six-sector economic accounting to examine policies to avert and to respond to a second wave. We find that a second round of economic shutdowns alone are neither sufficient nor necessary to avert or quell a second wave. In contrast, noneconomic NPIs, such as wearing masks and personal distancing, increasing testing and quarantine, reintroducing restrictions on social and recreational gatherings, and enhancing protections for the elderly together can mitigate a second wave while leaving room for an economic recovery. 

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5. Wave-averaged balance: a simple example

   https://doi.org/10.1017/jfm.2020.1032  

   Kafiabad, Hossein A.; Vanneste, Jacques; Young, William R. (March 2021, Journal of Fluid Mechanics)

   null (Ed.)

   In the presence of inertia-gravity waves, the geostrophic and hydrostatic balance that characterises the slow dynamics of rapidly rotating, strongly stratified flows holds in a time-averaged sense and applies to the Lagrangian-mean velocity and buoyancy. We give an elementary derivation of this wave-averaged balance and illustrate its accuracy in numerical solutions of the three-dimensional Boussinesq equations, using a simple configuration in which vertically planar near-inertial waves interact with a barotropic anticylonic vortex. We further use the conservation of the wave-averaged potential vorticity to predict the change in the barotropic vortex induced by the waves. 

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