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#1 |
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Master Poster
Join Date: May 2006
Posts: 2,136
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Keith Seffen WTC Paper Out
For all of you who do math better than I. It is via a troofer site, but I have no reason to doubt it is not valid.
http://winterpatriot.pbwiki.com/f/se...e_analysis.pdf |
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I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
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#2 |
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Downsitting Citizen
Join Date: Mar 2006
Location: In the argyle
Posts: 17,136
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Thanks, James!
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"Please, keep your chops cool and don’t overblow.” –Freddie Hubbard What's the Harm?........Stop Sylvia Browne........My 9/11 links |
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#3 |
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Master Poster
Join Date: May 2006
Posts: 2,136
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I tried to read it, but except for part of the intro and conclusion it was way over my head. At least I was able to get through all of the Poteshman paper on the stock options.
![]() Although I was disappointed to read the footnotes, and Judy Wood, David Ray Griffin and Jim Hoffman didn't get a single citation... |
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__________________
I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
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#4 |
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Downsitting Citizen
Join Date: Mar 2006
Location: In the argyle
Posts: 17,136
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Why, a child of four could understand Seffen's calculations! Unfortunately, it's too late here for me to corral such a child. I've verified as much as I can by counting on my fingers and by analyzing the patterns made by tossing cat whiskers onto beer coasters.
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__________________
"Please, keep your chops cool and don’t overblow.” –Freddie Hubbard What's the Harm?........Stop Sylvia Browne........My 9/11 links |
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#5 |
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Muse
Join Date: Apr 2007
Posts: 923
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The paper is due to appear in the Journal of Engineering Mechanics, Vol. 134, No. 2, February 2008. The current issue out is Vol. 133, No. 11 (November 2007). This looks like a draft version.
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#6 |
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Muse
Join Date: Oct 2007
Posts: 579
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#7 |
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Muse
Join Date: Oct 2007
Posts: 579
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Those factors responsible for the onset of collapse are now well established. Despite
localised and substantial horizontal impacts by fuel-laden aircraft, both towers survived until the intense fire compromised the ability of the remaining, in-tact columns close to the aircraft impact zones to sustain the weight of the buildings above them. The subsequent near free-falling of these upper parts over the height of just one storey resulted in dynamical “over-loading” of the relatively undamaged lower columns by a factor of 30 compared to their static load capacity, according to Ba?zant and Zhou (2002). "Free-falling... over the height of just one storey..." What a bunch of crap, that obviously did not happen and is not even possible with demolitions. |
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#8 |
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Master Poster
Join Date: May 2006
Posts: 2,136
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__________________
I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
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#9 |
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Muse
Join Date: Oct 2007
Posts: 579
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Cute... but this guy does not appear examine how far away from the truth "near" is.
This paper largerly appears to take the junk science served up by Bazant & Zhou, with their ludicrous multi-story "free fall" nonsense, and applies concepts associated with propagating instability phenomena to it. While it may be interesting to probe equation (21) for condition of "collapse" stop, the only other thing this paper may good for is to see if it predicts asymmetric "collapse" propagation. |
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#10 |
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Philosopher
Join Date: Sep 2006
Posts: 6,202
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__________________
Back home with a new sunburn...I look like a tomato. “Life may begin at 30, but it doesn’t get real interesting until about 150.” “Most motorcycle problems are caused by the nut that connects the handlebars to the saddle.” |
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#11 |
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Master Poster
Join Date: Jan 2007
Location: New York area
Posts: 2,250
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#12 |
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#4
Join Date: May 2007
Location: West of Northshore MA
Posts: 14,299
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__________________
Join the team, Show us what your machine can do (or just contribute to a good cause)Join the JREF Folders ! Team 13232 "Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley |
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#13 |
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Graduate Poster
Join Date: Mar 2007
Location: UK
Posts: 1,005
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Bofor's what don't you understand about Youngs Modulus that makes you think its "Junk Science" ?
IF you think its nonsense, the onus of proof is upon you to back your claim up with more than empty words. Instead of providing any scientific facts, your post just seems to be an attack Doctor Seffen for saying something that you do not like. Can you not understand that there are thousands of Keith Seffens out there, who though not having written a paper on the collapse, understand all too well the fatal effect fire had on the already damaged structure, and these guy's would be up in arms, had a demolition by explosive charges taken place. Instead they just get on with their lives with the knowledge that its blimmin obvious what occured. |
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#14 |
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Philosopher
Join Date: Jul 2007
Posts: 7,191
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__________________
No laws of physics were broken in the writing of this post |
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#15 |
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Muse
Join Date: Mar 2007
Location: Near Harmonica Virgins
Posts: 971
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From Wiki:
Gut feelings are generally regarded as unmodulated by conscious thought. Pretty applicable. From the paper, it appears "near" is approximately 0.5. Am I reading this correctly? |
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"You have done nothing to demonstrate an understanding of scientific methodology or modern skepticism, both of which are, by necessity, driven by the facts and evidence, not by preconceptions, and both of which are strengthened by, and rely upon, change." - Arkan Wolfshade |
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#16 |
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Keeper of the Kool-Vax
Join Date: Jul 2006
Location: The Far East...of Canada
Posts: 20,816
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So how long before we see a "Critical Analysis" of the paper by a Theologian or Song Writer at Scholars?
TAM
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#17 |
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Philosopher
Join Date: Oct 2007
Posts: 5,920
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#18 |
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Philosopher
Join Date: Apr 2006
Location: The armpit of L.A.
Posts: 7,857
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My compliments to Dr. Seffen, for a straightforward paper and a closed-form solution. The guy even gives us a Lagrangian.
That's one more peer-reviewed paper for the good guys. The opposition still stands at, let's see... carry the two... zero. Is there anyone out there who still thinks the Truth Movement hasn't forfeit the contest? |
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"Nothing real can defeat us. Nothing unreal exists." -B. Banzai VT VENIANT OMNES |
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#19 |
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Muse
Join Date: Mar 2007
Posts: 810
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#20 |
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Keeper of the Kool-Vax
Join Date: Jul 2006
Location: The Far East...of Canada
Posts: 20,816
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Maybe NWO Kitty could put them in touch with some "Purr" Reviewed Journals.
Thanks, I'll be here all week. TAM
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#21 |
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Illuminator
Join Date: Jul 2007
Posts: 4,602
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"Free-falling... over the height of just one storey..."
What a bunch of crap, that obviously did not happen and is not even possible with demolitions." Typical analysis by bofors, misreads the sentence, misquotes it, and argues from disbelief. Brother, bofors, i don't know why you bother. |
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#22 |
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Master Poster
Join Date: May 2006
Posts: 2,136
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Actually, let me get this straight, all we have been hearing now is how 110 stories of the towers fell at "free fall speed", "virtual free fall speed" or even my favorite "faster than the speed of gravity", and how that is impossible without the use of demolitions. So now is Bofors actually arguing that it is impossible for even one floor to collapse at "near free falls speed" even with the use of explosives?
Will you guys make up your mind already!!! |
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__________________
I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
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#23 |
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Illuminator
Join Date: Oct 2006
Location: Toronto
Posts: 3,875
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Can't wait to see the twoofers' reaction to this paper.
I suspect most of it will be along the lines of Bofor's in-depth analysis. |
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#24 |
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Philosopher
Join Date: Jul 2007
Posts: 7,191
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I can't get it to download. Is it available anywhere else?
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__________________
No laws of physics were broken in the writing of this post |
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#25 |
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Keeper of the Kool-Vax
Join Date: Jul 2006
Location: The Far East...of Canada
Posts: 20,816
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I am waiting for the first "Seffen is second cousins with the gardener who tends the White House lawn...clearly govt disinfo."
TAM
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#26 |
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Banned
Join Date: Oct 2006
Location: In a Little Cafe Just the Other Side of the Border
Posts: 7,091
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I've been trying to make the point that Griffin's retreat from the field of battle has nothing to do with me. It is a gesture of surrender that has everything to do with you (mostly) and, to a lesser degree, people like George Papcun and John Hotard. I don't say this to flatter you, but you have collapsed the house of cards. The near-total absence of criticism of your paper says it all. The fantasy movement is not fighting. They are screaming their mindless slogans to people who--they hope--don't know anything. They can't confront their opponents. You declared victory months ago, but now, thanks to Griffin, it's official. |
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#27 |
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Critical Thinker
Join Date: Jul 2007
Posts: 405
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Ive only just skimmed the paper very briefly, but in his model with no mass shedding, there is an average acceleration of 1/2g for crush down, if I remember correctly, the BLGB model had average accelerations for WTC 1 and 2 that straddled this figure, although with 20% mass shedding.
I'll obviously have to give the paper a more thorough look but this seems like an interesting result. |
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#28 |
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Banned
Join Date: Mar 2007
Posts: 1,426
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Interesting if true.....
And interesting anyway! But we do have the rather weak: "It is likely that the uppermost parts of the WTC towers were falling freely due to an absence of column resistance in the first weakest storey..." Where is the evidence for the truth of this statement? |
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#29 |
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Critical Thinker
Join Date: Jul 2007
Posts: 405
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#30 |
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Critical Thinker
Join Date: Jul 2007
Posts: 405
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Greening gives a value of tc for stage 1(crush down) as 11.6s and 9.7s for WTC 1 and 2 respectively. This is a pure momentum transfer model and ignores E1, the energy needed to destroy a floor.
Seffen's model gives crush down times of 8.3s and 7.3s when p*= 0, and values of around 12s for values of p* around 1. Considering the observed collapse times, that might be the final nail in the 'towers offered no resistance' coffin. |
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#31 |
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Critical Thinker
Join Date: Jul 2007
Posts: 405
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#32 |
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Banned
Join Date: Mar 2007
Posts: 1,426
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Dr. Seffen is another engineer who is apparently so enamoured of his own model that he fails to make the distinction between a theoretical/calculated result and a real-world observation/measurement.
Thus on page 18 of his paper we read: "The actual time for collapse of WTC 1 ranges from 8.3 seconds to 12.0 seconds, and for WTC2, from 7.3 seconds to 12.1 seconds..." It turns out that these collapse times are not the observed times but the calculated times! But then Dr. Seffen goes on to claim that his "actual" collapse times "embrace the observed period for both towers." Where has anyone claimed to have observed a crush down time of 8.3 seconds for WTC 1 or 7.3 seconds for WTC 2? This is complete BS and is being dishonest to say the least! Engineers!!!!!!!!!!!!!!!!!!!!!!! |
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#33 |
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Downsitting Citizen
Join Date: Mar 2006
Location: In the argyle
Posts: 17,136
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I have a copy here.
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__________________
"Please, keep your chops cool and don’t overblow.” –Freddie Hubbard What's the Harm?........Stop Sylvia Browne........My 9/11 links |
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#34 |
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Writer of Nothingnesses
Join Date: Dec 2006
Posts: 11,169
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I am totally and completely unimpressed. Do we really need mathematicians to prove to us that the WTCs collapsed? No we do not. Hey! I think somebody should write a sonnet on how the WTCs collapsed!!! Because THAT really would convince me! Poemize the doubters into submission!!! Yeah, baby!
I suppose this Seffen dude has nothing better to do with his time? 1. The WTC was standing. 2. A big fuel-laden projectile crashed into it at high speed. 3. Extensive damage was caused to the structure on impact. 4. Further damage was caused by explosion and fire that raged unchecked. 5. The WTC collapsed. How the hell difficult is that?!? Mathematicians. Sheez. Keep them away from me. Get them to work designing an anti-gravity system or something practical. Such as determining the temperature and time factor involved in creating the perfect baked potato. |
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#35 |
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Graduate Poster
Join Date: Jul 2007
Location: Spacetime
Posts: 1,554
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The tyranny of the model
Apollo20, There is a contemporary watercolorist named Frank Webb - a true hero of mine - who has taught art classes for eons. Webb uses the beautiful phrase "the tyranny of the model" to describe the vice-like grip that the model has on some. He says that in his experience there are those who can clearly differentiate between the model and the real world, and maintain the separation. He says that there are others who simply cannot keep the two separate, and that they are impervious to being taught the difference. The tyranny of the model grips the more uncreative scientists and engineers just the same. Given that a model is just a metaphor, this is really saying that the afflicted cannot differentiate between metaphor and reality. Having been a JREF for about 500 posts now, I see all the time those who confuse the NIST metaphor with reality. (It always reminds me of Joseph Campbell's terrific title to one of his books: Metaphor as Myth and Religion.) Got religion? Max ETA: For those who think the insights of a watercolorist are irrelevant to such hardcore sciencey stuff, remember, NIST - in using numerical methods to model the far-from-equilibrium dynamics of collapse initiation - is doing nothing more than painting portraits with noise. * * * |
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__________________
MAX-MIHOP: Thermite - an incendiary - was used to heat-weaken WTC steel connections, to initiate collapse. Jets served as ambiguity-reducing deception to make all of the experts certain, decisive and wrong that the WTC fires were solely jet-induced. The experts were so bewildered by deception planners' use of feedback - of hiding fire in fire - that no one thought to investigate for arson. That is how the WTC demolitions-by-heat-weakening were - and still are - hidden in plain view. |
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#36 |
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Banned
Join Date: Oct 2006
Location: In a Little Cafe Just the Other Side of the Border
Posts: 7,091
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#37 |
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Philosopher
Join Date: Apr 2006
Location: The armpit of L.A.
Posts: 7,857
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If I'm not mistaken, those times are the "free-fall" times from the impact zones of the two structures -- in other words, a theoretical lower limit.
I'm fairly certain nobody has claimed to have observed those times. While the model is imperfect to be sure, it's still a useful exercise in my opinion. None of the models are perfect. It is nice to see that they reasonably agree even when built with different assumptions. |
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"Nothing real can defeat us. Nothing unreal exists." -B. Banzai VT VENIANT OMNES |
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#38 |
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Graduate Poster
Join Date: Jul 2007
Location: Spacetime
Posts: 1,554
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Assume NOT CONTROLLED-DEMOLITION, and ye shall not find.
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__________________
MAX-MIHOP: Thermite - an incendiary - was used to heat-weaken WTC steel connections, to initiate collapse. Jets served as ambiguity-reducing deception to make all of the experts certain, decisive and wrong that the WTC fires were solely jet-induced. The experts were so bewildered by deception planners' use of feedback - of hiding fire in fire - that no one thought to investigate for arson. That is how the WTC demolitions-by-heat-weakening were - and still are - hidden in plain view. |
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#39 |
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Banned
Join Date: Oct 2006
Location: In a Little Cafe Just the Other Side of the Border
Posts: 7,091
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#40 |
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Muse
Join Date: Apr 2007
Posts: 923
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Originally Posted by Apollo20
The paper by Cherepanov also takes "free fall" for granted without making observations. A few months ago I posted on my observations of the collapse, doing what I've never seen anyone else doing, synchronizing the various videos with each other in order to develop a chronology of the collapse. It's not hard to do...anyone can do with a program like Premiere. I estimated that it took about 12 seconds for the first debris from the East Face of WTC2 to make land fall (counting from collapse initiation). But the second before the debris hit the ground, there were still columns standing at the northeast corner as high as the 78th floor (seemingly because the crushing upper block angled inward and missed the corner, as the ABC video recorded at 9:59:03 suggests). I find that remarkable, and it goes to show how complex the actual collapse was -- and only part of the collapse behavior was observable (much being hidden by the dust clouds). Then 14-16 seconds into the collapse, large chunks of debris were still falling as high as the 44th floor. And after most of the building had fallen to the ground, the lower part of the core still stood up to 25 seconds after the collapse started. |
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