beaches, ambiguity exists as to where to terminate the fitting or design. The parabolic
shape performs better for beaches with one headland, but it is more difficult to fit than
the log spiral and is sensitive to the choice of the control line.
The newly introduced hyperbolic-tangent beach provides good fits for one-headland
beaches and is more convenient to apply than the parabolic shape. Guidance was
developed for estimating equilibrium shapes with the hyperbolic tangent in
Luis Moreno acknowledges permission granted by CEDEX to publish this information.
Nicholas Kraus acknowledges permission granted by the Headquarters, U.S. Army Corps of
Engineers, to publish this paper developed under the Coastal Inlets Research Program, Inlet
Channels and Adjacent Shorelines Work Unit. Assistance of Dr. Jos Bueno in programming the
MatLab GUI is appreciated.
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