http://www.scubaboard.com/forums/as...-principals-article-text-dive-modeling-2.html
I'm reading one of your posts from 2007 (responding to LAJim) in which you gave a through answer (for the internet) as to the state of decompression theory past and present. I want to make sure I understand what you were saying and so I'm going to summarize and ask for clarification of a few points.
" Most tables older than twenty years are based on the limited supersaturation model. The Buhlmann model is one example. Physically these models are all incorrect as they assume de novo microbubble formation with decompression. The supersaturations are simply too small."
When you say the supersaturations are simply too small are you saying that the supersaturations are simply too small for bubbles to form solely as a result of the supersaturation (in the absence of pre-existing bubbles)?
When referring to traditional decompression models you say " The model is simple but impossible to reconcile with physics and physiology."
Are you referring to the lack of pre-existing bubbles in this model and are you also suggesting that half-times aren't fixed but change along with work load (referring to your studies in the later case)?
You say " Professor Buhlmann ascribed DCS to exceeding supersaturation in specific halftime tissues. No one else has ever found this to be true. I argued with him on this matter, but he was resolute."
Your argument was that DCS is not due to exceeding supersaturation in specific half-time tissues but rather what...? Growth of pre-existing bubbles or that we just don't know what causes it?
You mention that the bubble models are more realistic and regarding bubble distribution you say "Others such as Wienke’s model have a logistic distribution. In nature, such distributions are always power functions (see books on physical oceanography)."
Can you explain logistic vs power functions regarding bubble distribution?
Can you further explain this "The models will also vary as to whether they employ mass conversation (with respect to dissolved nitrogen) or assume that the bubble density is too small for this to matter. It is an unresolved issue."?
Explain mass conversation please.
Regarding nuclei origin I think your point is that some of it is random, some can be determined by traditional means and some of it is determined by exercise. Is that correct?
What I'm really looking for (in simple terms) is what your thoughts are regarding current decompression theory, what is clearly wrong, what is right and known for certain (if anything), and what a better model would need to address such as perhaps linear offgassing with exponential ongassing or parallel compartment modeling vs in series. What's important and what's not.
I understand that all of it works in practice due to the human trials that have gone on but that's outside of the theory (that's just empirical observation) and that's not what I'm especially interested in.
Thanks and I apologize for the length!
I'm reading one of your posts from 2007 (responding to LAJim) in which you gave a through answer (for the internet) as to the state of decompression theory past and present. I want to make sure I understand what you were saying and so I'm going to summarize and ask for clarification of a few points.
" Most tables older than twenty years are based on the limited supersaturation model. The Buhlmann model is one example. Physically these models are all incorrect as they assume de novo microbubble formation with decompression. The supersaturations are simply too small."
When you say the supersaturations are simply too small are you saying that the supersaturations are simply too small for bubbles to form solely as a result of the supersaturation (in the absence of pre-existing bubbles)?
When referring to traditional decompression models you say " The model is simple but impossible to reconcile with physics and physiology."
Are you referring to the lack of pre-existing bubbles in this model and are you also suggesting that half-times aren't fixed but change along with work load (referring to your studies in the later case)?
You say " Professor Buhlmann ascribed DCS to exceeding supersaturation in specific halftime tissues. No one else has ever found this to be true. I argued with him on this matter, but he was resolute."
Your argument was that DCS is not due to exceeding supersaturation in specific half-time tissues but rather what...? Growth of pre-existing bubbles or that we just don't know what causes it?
You mention that the bubble models are more realistic and regarding bubble distribution you say "Others such as Wienke’s model have a logistic distribution. In nature, such distributions are always power functions (see books on physical oceanography)."
Can you explain logistic vs power functions regarding bubble distribution?
Can you further explain this "The models will also vary as to whether they employ mass conversation (with respect to dissolved nitrogen) or assume that the bubble density is too small for this to matter. It is an unresolved issue."?
Explain mass conversation please.
Regarding nuclei origin I think your point is that some of it is random, some can be determined by traditional means and some of it is determined by exercise. Is that correct?
What I'm really looking for (in simple terms) is what your thoughts are regarding current decompression theory, what is clearly wrong, what is right and known for certain (if anything), and what a better model would need to address such as perhaps linear offgassing with exponential ongassing or parallel compartment modeling vs in series. What's important and what's not.
I understand that all of it works in practice due to the human trials that have gone on but that's outside of the theory (that's just empirical observation) and that's not what I'm especially interested in.
Thanks and I apologize for the length!
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