Added masses, damping, coupling terms and resistance as functions of the 

 frequency parameter and the Froude number. 



3. Forces experienced by wholly submerged bodies moving arbitrarily in a 

 non-uniform and non-steady field (Cummins' problem). 



4. Rectilinear motions of bodies moving at or beneath the corrugated water 

 surface. Pressure distributions. Diffraction effects. Exciting forces. 



5. The two-dimensional problem of a ship moving in a regular seaway. 



6. Ship moving on a straight course in a regular seaway. 

 Transverse stability in waves. 



Directional stability in waves. 

 Appraisal of the method mentioned under 2. 



7. Theory of resistance augmentation of a ship moving as under 6. 

 Appraisal of the method mentioned under 2. 



8. Propulsion in a regular seaway. 



9. Interaction between propeller and ship. 



10. Nonlinear problems of roll. 



11. Other nonlinear problems. 



1 2. Study of severe transient conditions. 



13. Irregular seaway. Correlation of model and ocean waves. 



14. Full-scale investigations (tests) on ships. Limiting data for accelerations 

 etc. 



15. Reductions of motion by artificial means. Roll and pitch stabilization. 



16. The general problem of speed increase in a seaway. Cavitation. 



17. Manoeuverability in a seaway. 



18. Development of ship forms with high damping qualities. 

 The influence of viscosity upon motions. 



19. Development of ship forms which experience low exciting forces in a 

 seaway. The investigation and appraisal of nonlinear effects. 



20. Development of the theory of impacts following various assumptions. 

 Horizontal impacts. 



21. Development of ship forms under water, above the surface, on deck with 

 respect to impacts. Theory of the behavior of hydrofoil craft in a seaway. 



ACKNOWLEDGMENT 



It was my aim to indicate the satisfactory scientific progress in our field and 

 to emphasize that application of its methods and results to problems presented by 

 practice can be made nowadays with much more confidence than before. The scientific 

 problems involved are both interesting and fruitful. Notwithstanding the age of our 

 profession we have by no means come to a blank wall, and there is no danger of the 

 status of diminishing return in research work which may decisively influence the future 

 development of the ship. 



A wide gap has been left in this report with respect to problems presented by 

 resistance and propulsion in a seaway due to reasons mentioned in the text which are 

 partly of an occasional, partly of a substantial character. It must be repeated that 

 special efforts are needed to promote solutions of these problems, which recently have 

 been somewhat neglected except by Japanese scientists. With respect to problems 

 presented by the irregularity of the seaway, reference is made to numerous excellent 

 papers published in this country. 



It is my opinion that because of the ample scope of the subject and the fast 

 rate of development, it is rather difficult for a single person to cope adequately with 

 the problem. The kind support given by the initiators of this symposium and by col- 

 leagues especially from this country encouraged me to present this lecture. It is 

 fortunate that thorough synopsis of the field is being prepared by Professor Korvin- 



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