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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. Gravitational wave memory and the wave equation

   https://doi.org/10.1088/1361-6382/ac7203  

   Garfinkle, David (June 2022, Classical and Quantum Gravity)

   Abstract Gravitational wave memory and its electromagnetic analog are shown to be straightforward consequences of the wave equation. From Maxwell’s equations one can derive a wave equation for the electric field, while from the Bianchi identity one can derive a wave equation for the Riemann tensor in linearized gravity. Memory in both cases is derived from the structure of the source of those wave equations. 

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3. Wave prediction using wave rider position measurements and NARX network in wave energy conversion

   https://doi.org/10.1016/j.apor.2018.10.016  

   Desouky, Mohammed A.A.; Abdelkhalik, Ossama (January 2019, Applied Ocean Research)
4. Near-Perfect Space-Wave to Surface-Wave Coupler Enabled Conformal Space Wave Transporting Metasurfaces

   https://doi.org/10.1109/TAP.2024.3352286  

   Budhu, Jordan (March 2024, IEEE Transactions on Antennas and Propagation)

   A technique for the design of conformal metasurfaces with two spatially disconnected space wave ports connected by a surface wave is presented. The passive and lossless metasurface absorbs the incident wave at port 1, converts it nearly perfectly into a surface wave which transports the energy along an arbitrarily shaped/curved metasurface to port 2, then reradiates the captured power as a radiated field with control over its amplitude and phase. Since the incident field is seen to disappear at the input port and reappear at a spatially dislocated port as a new formed beam, the space wave can be said to have been seamlessly transported from one point in space to another. The metasurface consists of a single, conformal, spatially variant, impedance sheet supported by a conformal grounded dielectric substrate of the same shape. It is modeled using integral equations. The integral equations are solved using the method of moments (MoM). The impedances of the sheet are optimized using the adjoint variable method to achieve the near perfect wave transportation operation from a passive and lossless metasurface. MATLAB codes and COMSOL Multiphysics simulation files for all designs presented in this paper are available for download as supplemental material files. Possible applications include channel optimization for cellular networks, inexpensive power harvesting, sensing, around-the-corner radar, and cloaking. 

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5. 1.4m Wave

   https://doi.org/10.17603/ds2-2vwe-tz62  

   Pyke, Christopher (January 2022, Designsafe-CI)

   Testing of Tsunami waves against a reinforced concrete core wall. The specimen was instrumented with three different types of instruments to measure load, pressure sensors on the front face of the specimen, strain gauges on the piles that supported the specimen, and load cells measuring the total force on the setup. The test specimen was placed inside a soil box with three different levels of soil examined to determine if changing the soil level changed the force in the support piles. Steam-wise force data was averaged across all trials for a given soil height and is presented for the three different force measurement techniques for the three different soil heights investigated. Wave gauge and ADV measurements are averaged across all trials for the given wave height. 

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