Mori 3 Inui and KaQitani 



N N 



m(£) = S a cosn7r£'+ J^ b sizi tltc? {o<£ <\) (8) 



n = 1 n n = 1 n 



where . 



V =-y (l ^ ( ^^l) (9) 



Using above expression for m(£), we divide the distribution 

 plane into M number small meshes, and assume that within the mesh- 

 es the source strength is constant, then the wave profiles are given 

 by N , 



Ux,y) = H aC (x, y) + b S (x, y)> (10) 



n J n n n n I 



n = 1 I / 



with 



M 



C (x,y) = 2-j cos n^'. G.(x, y ;F., to) 

 i = 1 



M 



S (x, y) = £jt sin n7r£. . G.(x, y ; £., to) (ll) 



n ^^ . 11 l 



i=l 



where 



G.(x,y;{.,to) = -^±j jf^ df] 1+ ' ^G(x, y, z , i, o, {) % __ Q d? {12) 



By preliminary studies of Equations (8) and (10) , five term 

 truncation N = 5 are found suitable. Then 5 x 2 = 10 numerical 

 coefficients jai , |b I (n= 1,2, ... , 5) are determined by the 

 least square method. 



Table 1 shows an example of such preliminary studies. Start- 

 ing with the wave profiles which are calculated from the hull -generat- 

 ing source m(£) of the model M21 at the speed of Fn = 0. 2887 

 (K Q L = 12), the wave analyzed sources m(£) are obtained for the 

 cases N = 4, 5, 6 and 8 . 



Figures 2~4 _also show the general features of the contribu- 

 tion function G^(x,y;^,to) as expressed in Equation (12). 



690 



