HANNA: DESIGN OF TRANSMISSION LOSS EXPERIMENTS 



But those models have been able to account accurately — and by 

 accurately I mean the mean discrepancy of the order of a dB — 

 using the type of model we have been talking about so far in the 

 workshop. 



However, I have to say that I have no evidence that we have done 

 justice to the systems designer. I guess he is going to have to tell 

 us precisely where he thinks we have fallen down, because we haven't 

 been able to account for the performance of this system. 



Mr. Geddes: Regardless of how we process the data, we scale 

 these records. We find an arrival on the records the amplitude of 

 which is the largest thing on the record. It's there, record after 

 record after record. 



So that, regardless of the explanation for it, I still have the 

 situation of looking at an arrival which I can look at on the records, 

 I can listen to it, and I can measure its amplitude. 



Dr. Hersey. There is only one problem with what you just said, 

 Will. That is what is known as a disallowed area of concern. I 

 disallowed it about 15 minutes ago. 



Dr. G. B. Morris (Marine Physical Laboratory, Scripps Institution 

 of Oceanography) : I think use of models in planning experiments and 

 comparisons of the models with the experimental data have to be done. 



Some of the examples that were shown are sort of extremes in that 

 you compare model data which have a very, very fine resolution with 

 experimental data which have a very long averaging time to very poor 

 resolution. It's the type of example that even experimentalists would 

 not think of doing, comparing a propagation curve that has, say, 

 values every few hundred yards, with another one that might have values 

 every few miles, except in a very gross manner. 



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