Contents 



Introduction and Review 



of Current Methods 1 



1.1 Background 1 



1.2 Methods for the Interpretation of 



Irregular Wave Records 3 



1.2.1 Global Methods 4 



1.2.2 Local Methods 11 



Two Dimensional LFI Theory 15 



2.1 Problem Formulation 15 



2.1.1 Dynamics 18 



2.2 Finding the Solution 20 



LFI Method for a Point Pressure Record 21 



3.1 Formulation of Solution 21 



3.2 Formulation of the Optimization 23 



3.3 Computation Methods 25 



3.3.1 Pre-Processing of Record 26 



3.3.2 Optimization Procedure 30 



3.4 Theoretical Records 35 



3.4.1 Choosing Parameters of Solution 40 



3.5 Laboratory Measurements 50 



3.6 Discussion 56 



Three Dimensional LFI Theory 59 



4.1 Three Dimensional Seas 60 



4.2 Problem Formulation 60 



4.3 Formulation of the Solution in each Window 63 



4.3.1 Background 63 



4.3.2 Dynamics 66 



4.4 A Local Two-Intersecting- Wave Theory 67 



