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PfcAJ
Contributor
Simon will try to convince you that arbitrary limiting range numbers (0.2-1.35), are some how valid. They are not. They are simply vastly under/over stated values to prevent false data and bad settings from being entered into a program. Standard practice in computing. But that does not imply any validity to those extreme settings.
The actual VPM range was in the 0.7 to 1.05 area. The VPM-B range is 0.55 to 0.825 region.
Beware of Simon trying to justify extending VPM-B into over-bloated plans that do not exist, and cannot be made or purchased anywhere.
.
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Hello Ross,
It appears you will say anything, even if it is patently false, in an attempt to win an argument on the internet.
Although this debate is a little tangential to the thread, the above statement in your post is a good illustration of your posting ethics.
The +7 conservatism designation for VPM-B corresponds to an initial critical bubble radius in the VPM calculations of approximately 1.01um, as shown here:
So, with that in mind, here is an extract from a description of the VPM-B model by its creators (bold underlined emphases are mine) [1]:
And here is an extract from Baker's original Fortran code (the bold emphases are mine):
VPM-B Fortran Program PROGRAM VPM-B
C Varying Permeability Model (VPM) Decompression Program in FORTRAN
C with Boyle's Law compensation algorithm (VPM-B)
C Author: Erik C. Baker
C "DISTRIBUTE FREELY - CREDIT THE AUTHORS"
C This program extends the 1986 VPM algorithm (Yount & Hoffman) to include mixed gas, repetitive, and altitude diving. Developments to the algorithm were made by David E. Yount, Eric B. Maiken, and Erik C. Baker over aC period from 1999 to 2001.
IF ((Critical_Radius_N2_Microns .LT. 0.2) .OR.
* (Critical_Radius_N2_Microns .GT. 1.35)) THEN
CALL SYSTEMQQ (OS_Command)
WRITE (*,903)
WRITE (*,900)
STOP 'PROGRAM TERMINATED'
END IF
This unequivocally proves you are the one who is "making stuff up". +6 (critical radius ~0.9 microns) or +7 (critical radius ~1.0 microns) is well within the parameters of the original VPM-B model (0.2 - 1.35 microns) and the only reason these more conservative iterations are not in your VPM software is because you chose, for reasons best known only to you, not to put them there.
I am in Washington for the Office of Naval Research Program Review, and have just spent the evening with David Doolette who has performed the majority of this work for NEDU. He performed the integral supersaturation analysis for the NEDU deep stops report. He confirms that "relevant" in the statement I posted here refers to ALL cells that are supersaturated (just as they were treated in UWSojourner's analysis) and that there is no "sparse spacing" as you claim. He also tells me that he has explained this to you before. Yet here you are, wilfully providing false information to the community in an attempt to win an argument on the internet.
Ross,
I devote large amounts of my time to representing the diving science literature on the internet because the bridge between that literature and the community is tenuous. I personally think this disconnect between science and end user is a very unfortunate situation and one worth striving to change. As such, I am very happy to discuss issues of curiosity or concern to forum members. I have discussed this particular issue with you over many forums and years.
However, as has been demonstrated over the last few pages of this thread, you have no hesitation in repetitively making authoritative statements about matters that, at best, you don't understand, or more likely, you know to be untrue. Worse, you continue to do this despite being told you are wrong by experts who (as here and many times in the past) go to considerable trouble to provide proof of such. It is my opinion that this campaign of systematic disinformation causes immense harm to the knowledge base of the community, and that you provide little benefit. You are not worth the time and effort, and I hope that the recent events of this thread have adequately demonstrated your lack of credibility to the forum members. It is my intention to stop discussing these matters with you on this forum.
Simon M
1. David E. Yount, Eric B. Maiken, Erik C. Baker, Implications of the Varying Permeability Model for Reverse Dive Profiles, Reverse Dive Profiles Workshop, October 29 and 30, 1999, Smithsonian Institution, Washington, D.C., Pg14:
It appears you will say anything, even if it is patently false, in an attempt to win an argument on the internet.
Although this debate is a little tangential to the thread, the above statement in your post is a good illustration of your posting ethics.
The +7 conservatism designation for VPM-B corresponds to an initial critical bubble radius in the VPM calculations of approximately 1.01um, as shown here:
So, with that in mind, here is an extract from a description of the VPM-B model by its creators (bold underlined emphases are mine) [1]:
A range of initial radii from 0.2 μm to 1.3 μm was selected on the basis of experimental values (Yount, Yeung, and Ingle 1979 and Yount, Gillary, and Hoffman 1984).
And here is an extract from Baker's original Fortran code (the bold emphases are mine):
VPM-B Fortran Program PROGRAM VPM-B
C Varying Permeability Model (VPM) Decompression Program in FORTRAN
C with Boyle's Law compensation algorithm (VPM-B)
C Author: Erik C. Baker
C "DISTRIBUTE FREELY - CREDIT THE AUTHORS"
C This program extends the 1986 VPM algorithm (Yount & Hoffman) to include mixed gas, repetitive, and altitude diving. Developments to the algorithm were made by David E. Yount, Eric B. Maiken, and Erik C. Baker over aC period from 1999 to 2001.
IF ((Critical_Radius_N2_Microns .LT. 0.2) .OR.
* (Critical_Radius_N2_Microns .GT. 1.35)) THEN
CALL SYSTEMQQ (OS_Command)
WRITE (*,903)
WRITE (*,900)
STOP 'PROGRAM TERMINATED'
END IF
This unequivocally proves you are the one who is "making stuff up". +6 (critical radius ~0.9 microns) or +7 (critical radius ~1.0 microns) is well within the parameters of the original VPM-B model (0.2 - 1.35 microns) and the only reason these more conservative iterations are not in your VPM software is because you chose, for reasons best known only to you, not to put them there.
I am in Washington for the Office of Naval Research Program Review, and have just spent the evening with David Doolette who has performed the majority of this work for NEDU. He performed the integral supersaturation analysis for the NEDU deep stops report. He confirms that "relevant" in the statement I posted here refers to ALL cells that are supersaturated (just as they were treated in UWSojourner's analysis) and that there is no "sparse spacing" as you claim. He also tells me that he has explained this to you before. Yet here you are, wilfully providing false information to the community in an attempt to win an argument on the internet.
Ross,
I devote large amounts of my time to representing the diving science literature on the internet because the bridge between that literature and the community is tenuous. I personally think this disconnect between science and end user is a very unfortunate situation and one worth striving to change. As such, I am very happy to discuss issues of curiosity or concern to forum members. I have discussed this particular issue with you over many forums and years.
However, as has been demonstrated over the last few pages of this thread, you have no hesitation in repetitively making authoritative statements about matters that, at best, you don't understand, or more likely, you know to be untrue. Worse, you continue to do this despite being told you are wrong by experts who (as here and many times in the past) go to considerable trouble to provide proof of such. It is my opinion that this campaign of systematic disinformation causes immense harm to the knowledge base of the community, and that you provide little benefit. You are not worth the time and effort, and I hope that the recent events of this thread have adequately demonstrated your lack of credibility to the forum members. It is my intention to stop discussing these matters with you on this forum.
Simon M
1. David E. Yount, Eric B. Maiken, Erik C. Baker, Implications of the Varying Permeability Model for Reverse Dive Profiles, Reverse Dive Profiles Workshop, October 29 and 30, 1999, Smithsonian Institution, Washington, D.C., Pg14:
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This is word a play game you are using there..... there are just two cells in that nedu stops paper... one slow, one fast, which essentially do not overlap. Therefore my statement is correct - the NEDU used widely or sparsely spaced data points, that do not overlap. Same for the pDCS stuff - two or four sample points, not 16.
Wrong. The Simon Mitchell / UWSojourner (Kevin Watts) version of ISS uses all 16 cells for a purpose they where not designed for. The 16 cell parallel model's that we use today, cannot be converted into serial model data points like you are attempting to do. All you get is one one giant number, but deco and stress is more complicated that this. Your method has no concept of stress or risk levels, cannot separate the difference from life threatening to harmless profile. Your ISS method is junk science.
*********************
Looking at this.....
Simon, can you please show me in that yellow bar, where does the deep stop occur and how big is it? Where is the S curve placed, and how does it affect supersaturation? How much influence does the shallow stop have, and where can I see this in that yellow rectangle shape?
.
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No it isn't.
I think this was an attempt to steer the discussion into a context in which you think you probably know more than Simon.
However, it is the first time I can remember that you've said something about computer science that triggered me to think that you may not know as much about that as you try to make people think either.
I've previously said that I deleted Vplanner after getting to know you because I wasn't willing to use a product that I know to be created by an unrepentant POV warrior. Your ideas about deco theory raised a serious red flag for me.
However, in THIS post you said something that makes me think that you may have programmed the model to continue functioning outside of its boundary conditions so that it at least continues to function *within* its boundary conditions. That's just bizarre and extremely risky for the user.
You could compare that to programming an X-ray machine to continue working even when it's delivering a fatal dose of radiation in order to be sure that it works in the conditions it was designed for. To me this raises a very serious red flag about your approach to programming! This is not "standard practice in computing". Writing a program that continues to function outside of its boundary conditions is the worst sin you can make as a programmer!
I would think that if you ever want to sell another copy of your program that you probably shouldn't talk any more about programming computers on scubaboard. The board is bulging with engineers and computer people who will, I"m sure, be happy to debate your POV about computer programming the way Simon has tried to debate your POV about deco theory. You'll only further undermine your reputation if you do that. To my way of thinking the only thing that you still have going for you is some people's belief that your products are probably well implemented.
Based on what you said right there, I am literally shocked and concerned that this may not be the case at all.
R..
This code started as a FORTRAN code base, in the 90's, run in a DOS command. Its configuration is made in a hand typed text file, which you did in notepad. Its has to be perfectly formatted to work. Very easy to make text errors.
Yes, programmers put in arbitrary limits either side (bounds checking), to make sure the program is actually reading valid configuration data, and not garbage data from a wrongly formatted text files. That typed text has to be converted to real numbers, so wide range check are in place to make sure it reads 65 and not 6 5 or x6 or ; or , any other invalid character (or more modern problems).
The code above.... translated it says... if not within this range, terminate program. i.e. validated the input.
But if you want to pretend their is some authenticated values here, well that is your mistake.
.
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The Chairman
Chairman of the Board
Why not let Dr. Mitchell speak for himself? Putting words in his mouth and otherwise twisting what he says is disingenuous and petty.
We certainly appreciate the time spent and I agree with you that the bridge is "tenuous" at best. In fact, it only exists because of your commitment to us. Accolades to Dr. Doolette for his interjections as well.
Doolette, Mitchell, and a few others have dedicated their time, resources and intelligence to understanding, researching and digesting the research of others in decompression theory. Their end game is pure science and understanding and I trust that. I trust that implicitly. That they share this with us is invaluable. On top of the discipline to become researchers and/or medical doctors they've also committed themselves to improve our understanding in hopes that we can dive a bit more safely. I just can't express my gratitude adequately. You guys are real heroes in my book.
The real problem is that a few people want to be "experts" in this field without putting in the discipline required. They have a nebulous concept of how they want it to work and are hell bent in pushing that concept on people looking for a toehold on the deco cliffs of insanity. It would appear that they see their way to being seen as an expert is to show themselves smarter than the real experts. Out of this confusion, Ratio Deco was born and promoted as a viable protocol to juggling deco obligations. It's not based on science but rather a hunch filled with holes and fallacies. It's why it didn't fare well in the Spisni study. Faith-based protocols usually don't do well when exposed to the scientific method.
For the readers who are still trying to decide who to believe in all of this, I offer some advice in the form of a list...
- Go with the science
- That means go with the scientists who research this and have real degrees
- You'll see they are often the ones not quite as certain as everyone else
- The more you know, the more you realize how little you know!
- They cite studies
- Often they conduct studies
- They are reasonable and patient with those who disagree or don't understand
- Avoid the science deniers
- They are overly confident of their understanding
- Cries of "Fake Science" and such are clues here
- They deny or dismiss the facts rather than enfold them
- They often seem paranoid (mostly because they are)
- They often sound angry and lash out at those who disagree
- They often push conspiracy theories
- They resort to name calling and innuendoes since facts and logic won't support them
- They are unreasonable with little patience
- Look to the Scuba Industry
- Who do the PDC manufacturers trust?
- Who do the training agencies trust?
- How many promote a particular protocol?
- How many outright reject that same protocol?
- Who do the reasonable people here on ScubaBoard trust?
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