Chryssostomtdts 
for the determination of the calm water resistance of a given ship is 
extended to permit the determination of the seakeeping qualities of a 
ship operating in a seaway. The preliminary results of such an effort 
are given in Reference 3 where the results for heave amidships, 
pitch, wave bending moment amidships, added resistance, accelera- 
tion at stations 0, 5, 10, 15 and 20 and relative motion and velocity 
at stations 1, 2, 3, 4 and 20 ofa ship operating in long-crested 
head seas can be found tabulated. The results are given as a function 
of : 
Froude No. 0. 105(0..05) 0.30 
H 1/3 7 Bp 0.015, 0.020, 0.025, 0.030, 0.040, 0.050, 0.075 
and 0.100 
LBP/B 5.50 (1::50)68550 
B/T 2.00 (1.00) 4.00 and 
CB - 0.55 (0.05) 0.90 
and are applicable for cruiser stern type ships. 
The 72 hull forms, the six Froude Numbers and the eight 
non-dimensional sea states (H 13 / LBP) defined above form a grid 
which allows the user to predict the seakeeping qualities of his ship 
by interpolation (extrapolation) with all the accuracy called for in the 
first iteration of the proposed design methodology. A sample table 
from Reference [3] is included in Appendix I of this study for the 
reader's convenience. 
Il,2. Mathematical Model 
The following describes the method employed in the present 
study to determine the values of independent variables of the system 
that will best satisfy an owner's given set of requirements. 
a) Assign different combinations of values to the independent 
variables. 
b) Evaluate the mathematical equations describing the sys- 
tem under investigation for each combination of values of the 
independent variables (each evaluation constitutes a sampling 
cycle of the optimization procedure). 
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