PORTER: SOFAR PROPAGATION OF WIDE-BAND SIGNALS TO LONG RANGES 



Dr. Hersey: I know of one isolated experiment, which was a very 

 elaborate one, on bottom bounce by Hastrup at La Spezia, in which he 

 worked out the impulse response for explosive shots of reflections 

 from the bottom. But, if you have ever tried to read that paper, 

 really read it, it is a rather confusing thing to interpret. 



I, too, regret that there isn't more of that type of presentation 

 in this workshop. There may be before we get through. But I wondered 

 if you could give us a thumbnail sketch of what the models that you 

 refer to will do, because I think we ought to get a description of them 

 as an important key part of this workshop. 



Dr. Weinberg: The particular program I was talking about is a 

 couple of years old and is called PEAK or PASSIVE, I don't know which. 

 It was designed by Howard Newman of our lab and Jeff Colling. It's 

 really just a "brute force" model. It allows you to input various 

 characteristics. It tries to take into account various character- 

 istics of systems rather than an explosive source. But I'm sure it 

 could do that as well. It's not a very elegant program, but it does 

 allow you to do broadband analysis. 



My point wasn't that we had a ray program. Just the fact that 

 nobody is really aware of the type of programs that we do have. 



Dr. Hersey: Well, I guess I have to say that that is the 

 responsibility of the people who do know about the program. The 

 attendance at the workshops has been broad. Don't you agree? It 

 may not be a very serious mistake, but it is a defect that we have 

 to correct. 



Dr. Weinberg: The type of program that we were talking about 

 really didn't come up in any of the workshops so far. The first 

 workshop was basically a ray tracing workshop. The second one was 



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