(9) Local wave height deviation from the average (D^) — calcula- 

 ted by subtracting Hy^ from each H£ and then removing any long waves 

 or tank oscillations from this curve by subtracting the local Q^ value 

 from each Hj> (calculation is performed by the program WVHTCN, which 

 then plots Dp as a function of tank position) . 



(10) Amplitude of local wave height deviation from the average 

 (A) --the amplitude of the best fit size curve to the plot of D£ versus 

 tank position (computed by program WVHTC2) . 



(11) Reflection coefficient ( 'K R ) -- calculated by dividing A by 

 Hy. This procedure for estimating Kr is referred to as the automated 

 method in Volumes I to VII. A manual method for determining K^ is 

 described in Volume I, which also contains a description of the automated 

 method. Most K^ values in this volume were obtained with the automated 

 method. The K^ values not determined directly by the automated method 

 were determined by the manual method and adjusted by an amount equal to 

 the average difference between the two methods to make the values com- 

 parable to the automated %'s. Volumes II to VII contain further infor- 

 mation on this difference. 



b. Conceptual Terms . The following terms describe the different 

 physical components of the deviation of the water surface from the still- 

 water level. 



(1) Reflected wave height (H R )--the height of the seaward- 

 traveling waves which have been reflected from the profile. Waves are 

 reflected from any segment of the profile where the depth change is 

 significant; i.e., the depth change is an appreciable fraction of the 

 average depth over a horizontal distance less than one wavelength. Thus, 

 waves can be reflected from more than one segment of the profile so that 

 more than one reflected wave component with the same period may be 

 present. However, over the constant depth section of the wave tanks 



the various components superpose, and in effect, they become a coherent 

 reflected wave. The amplitude, A, of the deviation of the local wave 

 height from the average (defined above) is a measure of the reflected 

 wave height, Hp, in the constant- depth section of the tank. Hp is 

 also equal to the product of Kp, and Hj. Hj is defined in (3) below. 



(2) Re-reflected wave height (H RR )--the height of the shoreward- 

 traveling wave which has been reflected from the profile and then reflec- 

 ted from the wave generator. This wave height is the product of Hj, K p 

 of the profile, and the reflection coefficient of the generator, K^. 

 Since wave filters were not used in front of the generator in the LEBS 

 experiments, K^ is assumed to be 1 and thus H^ is equal to Hp. 



(3) Incident wave height (Hj)--the height of the shoreward- 

 traveling wave that results from the superposition of the nominal gene- 

 rated wave height, H^, and the re-reflected wave height, Hrr- Hj 

 varies with time as the phase difference between H^> and the generator 

 motion varies. At any given time, Hj is equal to H^ (defined above). 



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