Son of Deep Stops *or* Waiting to be merged with the mother thread...

[rossh]

what do you think regarding BW's comments pre release that the NEDU was like RGBM then...crickets after?

There is an interesting back story to that. In 2004 it was going to be as Bruce said, and it was going to be good - a real model comparison. At least that's how he explained it.

And then..... look what the nedu did instead. Two obscure shallow test models... that have no connection to tech diving (or any model for that matter) . Of course the nedu is not here to test tech models either - they work on navy designs only. So we can't get too disappointed, or perplexed that the nedu profiles are not related to tech diving. Only people who can see the connection, are those with an agenda.


For a while there a few years ago, Simon and friends tried to show us an RGBM profile that they said matched. But when we pointed out that they had added the times up the wrong way, they withdrew it. Not surprising though - deco research is riddled with simple mistakes in reading profiles and plans and model output.

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[rossh]

I have to admit that I sometimes feel as dumb as a box of wet hammers when I follow this conversation. Other times I think I might be losing my mind a little.

This is one of those times... both of them.
Because when I read your supporting document it seems to say the exact opposite of what you are trying to make as a point.

Do you see anything that makes the nedu test of imminent urgency? I don't. Do you see anything that justifies Simon adoption entirely one side of the discussion points, to the exclusion of all others? I don't. Perhaps you would like to read the 20+ pages of discussion that lead up to that summary here:

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[oya]

20+ pages of discussion

I am reasonably certain of two things:
1) you are familiar with the phrase "copyright infringement."
2) nowhere in those pages does it say, "VPM is awesome, let's just keep doing that because we're done with science and there's nothing left to know!"

 

[rossh]

I am reasonably certain of two things:
1) you are familiar with the phrase "copyright infringement."
2) nowhere in those pages does it say, "VPM is awesome, let's just keep doing that because we're done with science and there's nothing left to know!"

1/ They are out of print, and I have a copy and you don't... Fair use.
2/ Silly statement....

 

[kensuf]

We all know you have fallen in love with GF Kevin. But it has warts, including the faults I have described.

If you want to keep using it to make grossly over-inflated plans, and expect them to be taken seriously, then its time to fix the mistakes in the current GF method.

Don't try to turn the attention to VPM-B. VPM-B is still the most current, the most accurate, and the most reliable planning model we have. By comparison, ZHL-C has been soundly stepped over and patched up with GF a hundred different ways.

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Hi Ross.

I'm planning a dive at Eagle's Nest in a couple of weeks. Average depth will be 250'. Bottom time will be between 80 and 100 minutes. I invite you to come along and deco out of the dive on the algorithm of your choice, but I'll choose to use ZHL16 w/GF's.

Hugs,

Ken

 

[kensuf]

Here is a little history....

From 2003 onwards, the gold standard was VPM-B and it was used widely. Most in GF land tried to copy it and did dives just like it. In DIR land, they pretty much did the same thing. We have a very successful decade of dives on this approach, and records show this. More than half the world followed this approach in some format. VPM-B has been to great depths and used as is in many different dives successfully.

Then the DIR crowd got a little too confident, and started doing some things that were not right.


And Then ..... one day, and man named Simon came along and told us it was all broken, but its OK because he knows how to fix it...... that is where we are now. Except he hasn't fixed anything - nothing was broken .... He just made a big mess instead


.

Actually, I used to dive a bit with the guys that were implementing VPM style algorithms on a regular basis between 1996 and 2000. The incidence of DCS was pretty high, but we usually just sucked it up and chewed advil (a guy named George used to pop advil starting at 70' like it was going out of style) because of ego and peer pressure.

 

[UWSojourner]

There is an interesting back story to that. In 2004 it was going to be as Bruce said, and it was going to be good - a real model comparison. At least that's how he explained it.

And then..... look what the nedu did instead. Two obscure shallow test models... that have no connection to tech diving.

So let me get this straight. You're claiming that the NEDU held a workshop with decompression researchers (see list below from NEDU TR 11-06). The expressed intent of the workshop was to allow the participants to peer review the study and critique it PRIOR to the actual dive trials. This was meant to be a "speak now or forever hold your peace" event.

After the workshop, B. Wienke posts this ...

... where he clearly seemed excited about the live dive trials and described the deep stop profile as "RGBM-like" (see here). His description makes sense because the tested deep stop profile is truly RGBM-like and VPM-like (see here).

So your position is that sometime after Wienke and the other researchers attended the workshop where all the participants were briefed, the NEDU simply changed the profile and tested something entirely different? That's your position???? Really?????

Isn't it much more likely that the NEDU just did the test they told the peer review group they'd do? And the results were very inconvenient for some people who had a financial interest in a certain outcome? Doesn't that seem like a more credible explanation to you? It does to me.

 

[lowviz]

They are out of print, and I have a copy and you don't... Fair use. ...//...

I was waiting for the "L" card to be dealt.

Ross, since I am obviously looking for patterns in your work, the phrase "reverse engineering" clearly applies. You have a right to protect your intellectual property. Are you OK with me messing? This sort of thing would normally be done with a mutual non-disclosure agreement signed by both parties and blessed by both sets of lawyers. Such is pointless here. This is SB, if you can't yap about it then it is not worth the effort to tease anything out. No prob either way.

But at the moment, I'm completely fascinated by the possibility of smoothing out the experimentally based Navy Air Table 5 for the purpose of better modeling. (simpler equations)

Please continue, all. This is most interesting...

 

[C Dub]

Because when I read your supporting document it seems to say the exact opposite of what you are trying to make as a point.

You have come to the essential truth.

 

[Storker]

This is all very fascinating, but instead of rehashing the first deep stop thread, can we get back to current modeling?

Gradient Factors, as currently implemented, are a disaster.

Do you mean the way they're implemented in MultiDeco? I mean, that's your program, so that's the one you'd probably know most about.

Would you say that using ZHL-16+GF in MultiDeco is dangerous because the way it's implemented is a disaster?

And if the implementation is a disaster, can you recommend a program where ZHL-16+GF is implemented in a better way, so using it is not as dangerous as using MultiDeco apparently is?