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wcelliott
QUOTE
I got a flu/chest infection


I've recently discovered something that's worked for everything I've tried it on, colloidal silver.

It cured a chronic sinus infection that I'd had for years, and blepharitis that'd resisted four 6-week courses of antibiotics.

It's also been shown to be effective against a wide range of viruses, up to and including the AIDS virus.

You can get it at any health food store, I'd recommend getting some 10ppm colloidal silver in a spray bottle (~$12) and spritzing it up each nostril maybe five sprays, each, and another ten into your mouth, 4x/day until it goes away (probably two days, if my experience is any indication).

You can also just spritz it into your mouth as you take a deep breath to get it straight into your lungs.

It isn't toxic in any reasonable doses, so there isn't much risk.

I'd be interested in hearing if it works for you as well as it did with me.
David B. Benson
QUOTE (wcelliott+Aug 24 2007, 07:12 PM)
(Note, this is page 410, on the *second* thread on this topic.)

Third.
einsteen
What has smoke to do in a finite element simulation ? It looks like a normal video with some extra structure added to it. Or did they merge the two pictures ? I haven't watched the show yet and as far as I can see it doesn't really add something to what we know already or do not know already.
lozenge124
QUOTE (einsteen+Aug 25 2007, 08:22 PM)
What has smoke to do in a finite element simulation ? It looks like a normal video with some extra structure added to it. Or did they merge the two pictures ? I haven't watched the show yet and as far as I can see it doesn't really add something to what we know already or do not know already.

It's the simulation on top of a WTC video. The WTC video is where the smoke is coming from obviously, they appear to have placed the model on top to prove it out - ie. make it match the real tower.

The history channel program doesn't describe what the models are, and they are about 10 minutes apart. Just before one of them is shown, Matthys Levy ('debunker' structural engineer) says something about how they developed "analytical models" that showed the collapse and only fire and structural damage were necessary.The model video is then shown implying that this is his analytical model, though this isn't stated explicitly.

Levy was involved with the report developed for the Silverstein trial, so these models could be from there. They could also be from the NIST LS-DYNA models - which haven't been seen before AFAIK. I hadn't seen them before so I'd be interested to know.
OneWhiteEye
David B. Benson:

After spending considerable time killing off the weak and sick brain cells, I've achieved sufficient clarity to approach the problem of extracting small motion information from video. Never given it much thought before but it resembles other more familiar problem domains.

I've written a pair of scripts that produce einsteen images and extract pixel RGB information from selected ranges of frames, colums, and rows then outputs CSV files. This is the (very) easy part and is the only product composed of objective results and which contributes no error.

Do you consider spatio-temporally located red-green-blue values (the raw data) useful? I'd assume that the ideal case is (t, y(t)) pairs but, as you'd guess, there's quite a gap between that and the raw data. There are good reasons to apply corrections prior to aggregative procedures, which must precede the mapping from pixels to meters. I have my own ideas as to methodology but I gather that you have the tools to analyze datasets to isolate random and systematic error. My feeling is that it might be valuable to use such methods as a complementary approach to separating signal from noise and thus achieve greater confidence in the scaling.

The raw data looks like this:

QUOTE

170 209 0 187 196 202
171 209 0 173 182 188
172 209 0 181 191 196
173 209 0 187 197 199
174 209 0 193 203 206
175 209 0 178 186 189
176 209 0 181 189 190
177 209 0 184 193 194


where the record format is (all integers):
  • [optional] Video ID - associates data with a particular video source
  • [optional] Dump ID - associates data with a particular frame dump of a video
  • Frame - Frame number referenced to source video (relative time)
  • Column - horizontal pixel location
  • Row - vertical pixel location
  • Red - Red channel intensity (0-255)
  • Green - Green channel intensity (0-255)
  • Blue - Blue channel intensity (0-255)

It goes without saying that, lacking context and interpretation, a large collection of trash data can be generated in seconds. With a little context, the picture improves. The following series of graphs represent the 'passage' of a dark feature through adjacent vertical pixels 'at the onset of motion' (read that as early on). Each successive graph is the RGB intensities over time of the next pixel down. It looks like a detectable object passing by a series of detectors, because essentially that's what it is... if you ignore four other degrees of freedom as well as the associated effect on surface properties and incident light.

User posted image

User posted image

User posted image

User posted image

User posted image

User posted image

User posted image
OneWhiteEye
The above is not necessarily vertical motion (at all) but, if it were interpreted as only vertical motion along with a host of reasonable but potentially incorrect assumptions, one can develop datasets like this:

User posted image

The first series of points in blue are derived by one method, the later green ones from a second. Both were done roughly and could stand improvements too tedious to enumerate.

There are so many sources of contamination prior to numerical extraction. Many of these can be isolated if the data is processed correctly. The graphs above are raw in the sense that no error corrections have been applied. There are several similar candidate regions for analysis on this one video.

Let me know what sort of deliverable form you prefer.

------



If anyone has (at their fingertips) links to sources for good videos or detailed structural info about the antenna, and you're so inclined, I'd be much obliged.
Bryn Richards
In regards to the history channel video, I did like how they explained the psychology behind conspiracy theorists, and how such things are about the 'self', rather than about truth.

Basically, even if all conspiracy theories are debunked, there will still be fanatical conspiracy theorists out there, because they don't care about the truth, they just want their anti-government beliefs, to come true, to match the scale of the event.

The video argued "JFK, the most powerful man in the free world. Shot and killed by a nobody?? C'mon, nobody will believe that!" - The same thing applies with 9/11 conspiracy theorists. They don't want to accept, never ever, not in a million years, that it was a bunch of Arabs, sent by Osama, with 'box-cutters' (Scissors?) and flight training. Because yet again it's "A bunch of nobodies" carrying out this devastating attack. They just don't want to accept that it's really that simple.

And really, I think the solution behind all this, is basically to debunk ALL the theories, leave not a single one standing, and then inject some hardcore Islam education into these people, by people such as Robert Spencer.
shagster
QUOTE (Trippy+Aug 25 2007, 07:20 AM)
I don't know if you saw my post earlier, but Gypsum is an evaporite, and evaporites typically occur together, so it would not be unreasonable to expect that the Gypsum that was used conatined potassium impurities.  The two most obviouse sources would be Sylvite.

Probably a more likely source would be Polyhalite, or polyhalite like impurities in the Gypsum.  Polyhalite is also an evaporite and occurs as K_2SO_4 . MgSO_4 . 2 CaSO_4 . 2 H_2O

Some of the columns still had gypsum panels attached during cleanup operations. I don't know if the cleanup people cut away a piece of the panel then cut the steel each time or if they sometimes cut right into the steel through the gypsum. Some of the elements of the gypsum could have gotten incorporated into the steel during the cuts either way. Gypsum gives off a yellow-green smoke when torched. It's known that cutting steel with a torch produces microspheres in the 1 to 10 um range.

There was probably a thin layer of fireproofing on the perimeter columns, even though most of it got ablated away during collapse. Whatever elements were in the freproofing probably got into the steel microspheres when the perimeter columns were cut with the torches during cleanup.
Chainsaw,
QUOTE (Trippy+Aug 25 2007, 07:20 AM)
I don't know if you saw my post earlier, but Gypsum is an evaporite, and evaporites typically occur together, so it would not be unreasonable to expect that the Gypsum that was used conatined potassium impurities. The two most obviouse sources would be Sylvite.

Probably a more likely source would be Polyhalite, or polyhalite like impurities in the Gypsum. Polyhalite is also an evaporite and occurs as K_2SO_4 . MgSO_4 . 2 CaSO_4 . 2 H_2O

Sorry to hear you are sick hope you are in well soon.
I agree with you that duraluminum could have formed some spheres but given the chemical and physical properities of Duraluminum it is more likely that the spheres are of an organic origin.
The temperatures produced by oxidizing vaporized aluminum are 2800°C the vaporization point of iron is 2861 °C
The potassium would vaporize at those temperatures and would not likely be included in the spheres.
They hydrogen reaction with steel, organics, and aluminum oxide, or the combustion of small amounts of steel are more likely to form spheres because it is less energetic, also if duraluminum were the source should not all the spheres have a similar chemical foot print to the duraluminum in the planes?
That does not seem to be the case, so how is that explained?
I am looking into the fact that when compressed in volume that air releases heat into contained materials, explosive compression of a volume of air in the towers could have cause a dramatic rise in localized temperatures, and resulted if sphere formation, I tried an experiment of this but only recovered a 1/2 inch by 1/4th inch piece of the experiment, the rest was scattered in the air and blown away with the wind, forgot to factor in the hydrogen explosions strength into the experiment. biggrin.gif
wcelliott
QUOTE
I am looking into the fact that when compressed in volume that air releases heat into contained materials, explosive compression of a volume of air in the towers could have cause a dramatic rise in localized temperatures,


Please note that whenever I'm confronted by a "Jet fuel can't melt steel" CDiot, my standard response is, "Yes, it can, that's why we don't use steel in jet engines".

This response is sometimes criticized on the grounds that the conditions in jet engines are so different from room temperature and pressure that the answer is misleading.

But has anyone ever considered the environment *during impact*?

Jet engines compress the air prior to combustion, and at elevated pressures, the normal heat of combustion takes place in a smaller physical volume, raising the temperature. More fuel and more air in less space means a hotter flame.

Calculations of the fuel+air combustion temperature in the WTC towers were assumed to be at ambient pressure, but has anyone estimated the pressure spikes associated with the aircraft debris going 500mph through the fireball? There had to be a lot of localized pressure transients that would've significantly increased the temperatures of the flames, if only for scant milliseconds.

But then, how big were those spheres? Collisions between aluminum and steel make scrapings containing elements of each, and following debris compressing the fireball via turbulence instantaneously heating the scrapings beyond the melting point of steel...

Anybody have any idea of how to go about estimating the compression expected from 500mph aircraft debris?
Grumpy
wcelliott

There is also the consideration of the effects of a certain amout of heat energy on very small pieces. Instantanious flares of high temperatures would affect those very small pieces very rapidly (IE their temps would closely follow air temps and could have melted in milliseconds) where larger pieces would not show signs of melting because of their mass spreading heat(especially Aluminum).

Grumpy cool.gif
wcelliott
QUOTE
There is also the consideration...


Agreed.
Daru
Just for the record... kerosene burns at low temp.

In an open-air office fire such as that at WTC , kerosene will burn at around 500-700 degrees Fahrenheit.

"jet fuel burn very hot" is a myth.
adoucette
QUOTE (Daru+Aug 26 2007, 06:24 PM)
Just for the record... kerosene burns at low temp.

In an open-air office fire such as that at WTC , kerosene will burn at around 500-700 degrees Fahrenheit.

"jet fuel burn very hot" is a myth.

laugh.gif

Try again.

Consider, if you will, that the IGNITION temperature for paper is 451 F.

Consider that the adiabatic combustion temperature is 2150 °C for oil and 2000 °C for natural gas.

Consider that you have ZERO credibiliity.

Arthur
Daru
What some peolple seems to not understand is, that all information about burning fuel is availible on the net.

One can just research it...it will take some time.

People will only find "jet fuel burn very hot" myth, from OCTers talking about wtc.
wcelliott
QUOTE
Just for the record... kerosene burns at low temp.

In an open-air office fire such as that at WTC , kerosene will burn at around 500-700 degrees Fahrenheit.

"jet fuel burn very hot" is a myth.


Didn't I just say that some CDiot would post the "jet fuel won't melt steel" crap again?

Daru, the only people who are claiming that jet fuel DOESN'T burn hot are CDiots like yourself.

Fuel-air mixtures release HEAT when they burn, they DON'T burn at one specific TEMPERATURE. IF the environment is already HOT TO BEGIN WITH, then WHEN HEAT IS ADDED, IT GETS HOTTER!!!

When you COMPRESS the fuel+air mixture IT GETS HOTTER!!! First-semester Thermodynamics. Get a book from the library, look it up.

And jet engine manufacturers DON'T use steel in the hot sections of their engines BECAUSE IT'D MELT!!!

BUY A CLUE!!!
Chainsaw,
QUOTE (wcelliott+Aug 27 2007, 12:25 AM)

Didn't I just say that some CDiot would post the "jet fuel won't melt steel" crap again?

Daru, the only people who are claiming that jet fuel DOESN'T burn hot are CDiots like yourself.

Fuel-air mixtures release HEAT when they burn, they DON'T burn at one specific TEMPERATURE. IF the environment is already HOT TO BEGIN WITH, then WHEN HEAT IS ADDED, IT GETS HOTTER!!!

When you COMPRESS the fuel+air mixture IT GETS HOTTER!!! First-semester Thermodynamics. Get a book from the library, look it up.

And jet engine manufacturers DON'T use steel in the hot sections of their engines BECAUSE IT'D MELT!!!

BUY A CLUE!!!

wcelliott

Here I have to get on you for being intellectually Dishonest with Daru! wink.gif

Jet engines do not melt steel, they com bust Oxidize it similar to what an oxygen lance does. The steel is converted with air into Fe 304, and the jet engine either explodes or locks up resulting in failure of the engine crash of the plane and death of the crew and passengers.
I mean come on we are talking temperatures of 3000c produced by the oxidation of steel in the air stream.

The method of oxidation is critical to flame temperatures, not only does jet fuel com bust but it forms super heated steam as part of that combustion process, that can itself react as an oxygen source with reactive metals releasing hydrogen and that can go on where ever the conditions exist for entrapment of the super heated steam.
Saying that Jet fuel fires can not melt steel is stupid, because they produce other fuels merely by combustion in air that can melt steel easily. Those being Carbon Black, and water if elements that can convert it to hydrogen exist in the environment!
Chainsaw,
QUOTE (wcelliott+Aug 26 2007, 04:39 PM)

Please note that whenever I'm confronted by a "Jet fuel can't melt steel" CDiot, my standard response is, "Yes, it can, that's why we don't use steel in jet engines".

This response is sometimes criticized on the grounds that the conditions in jet engines are so different from room temperature and pressure that the answer is misleading.

But has anyone ever considered the environment *during impact*?

Jet engines compress the air prior to combustion, and at elevated pressures, the normal heat of combustion takes place in a smaller physical volume, raising the temperature. More fuel and more air in less space means a hotter flame.

Calculations of the fuel+air combustion temperature in the WTC towers were assumed to be at ambient pressure, but has anyone estimated the pressure spikes associated with the aircraft debris going 500mph through the fireball? There had to be a lot of localized pressure transients that would've significantly increased the temperatures of the flames, if only for scant milliseconds.

But then, how big were those spheres? Collisions between aluminum and steel make scrapings containing elements of each, and following debris compressing the fireball via turbulence instantaneously heating the scrapings beyond the melting point of steel...

Anybody have any idea of how to go about estimating the compression expected from 500mph aircraft debris?

Now your beginning to see why the fuel air explosions had caricteristics similar to a fuel air reactive metal slurry and why they spawn associated reactions in the towers on impact.

I actually did experiment on this, There are so many ways too make those spheres that to promote them as evidence of anything is laughable. Every time I look I find another way to create them although the easiest way is with organics not with aluminum, although it is possible.
adoucette
QUOTE (Daru+Aug 26 2007, 07:14 PM)
What some peolple seems to not understand is, that all information about burning fuel is availible on the net.

One can just research it...it will take some time.

People will only find "jet fuel burn very hot" myth, from OCTers talking about wtc.

Daru,

You are WRONG.

All your typical hydrocarbons burn at ~ 2,000 degrees CENTIGRADE in air.

See: http://en.wikipedia.org/wiki/Adiabatic_flame_temperature

In daily life, the vast majority of flames one encounters are those of organic compounds including wood, wax, fat, common plastics, propane, and gasoline. The constant-pressure adiabatic flame temperature of such substances in air is in a relatively-narrow range around 1950°C. This is because, in terms of stoichiometry, the combustion of an organic compound with n carbons involves breaking roughly 2n C–H bonds, n C–C bonds, and 1.5n O2 bonds to form roughly n CO2 molecules and n H2O molecules.

Arthur

wcelliott
QUOTE
Saying that Jet fuel fires can not melt steel is stupid,


Agreed.

My point was that jet engines, burning jet fuel as they normally do, create temperatures in their combustion chambers that would exceed steel's maximum working temperature. It would be more accurate to say that a jet engine made with steel components in the combustion chamber would fail due to the steel's inability to maintain structural integrity at elevated temperatures, but if somebody's so stupid that I need to point this out, then that explanation would probably just go over their head anyway.

Also, I'd still like the point I just raised to be considered further, about how much compression (and therefore temperature of combustion increase) one should expect from air being accelerated by aircraft debris going 500mph.

I'm not sure how to go about calculating the pressure increase, other than to assign random coefficients of drag to random-sized chunks of debris and assuming that the drag energy is compressing the air in front of it, inferring a delta-pressure*volume from the loss of kinetic energy of the debris. Then, the increased pressure combustion yields an increased combustion temperature.

Can anyone think of a more elegant approach? This one gives me a headache just thinking about it.
einsteen
OneWhiteEye,

Thanks for your information, I received your program to create the bitmaps and I got it to work. I'm a little bit busy (and weekends are always too short... ;-]) but will certainly use it later for a couple of videos in order to get an average value. The colour splitting RGB is a little bit beyond me. Didn't you also say in the past that the human eye is needed to judge the image ? In the case that smoke and dust covers a part of the fall we should use interpolation methods and take a look at the videos and pictures.

I think it is now a big challenge to determine the acceleration in the y direction of the block(s) if they wouldn't topple. They do of course but what would the value be if they don't, this is very important because if one uses 1d models you also need to correct for the toppling.
einsteen
QUOTE (wcelliott+Aug 27 2007, 12:25 AM)

Didn't I just say that some CDiot would post the "jet fuel won't melt steel" crap again?

Daru, the only people who are claiming that jet fuel DOESN'T burn hot are CDiots like yourself.

Fuel-air mixtures release HEAT when they burn, they DON'T burn at one specific TEMPERATURE. IF the environment is already HOT TO BEGIN WITH, then WHEN HEAT IS ADDED, IT GETS HOTTER!!!

When you COMPRESS the fuel+air mixture IT GETS HOTTER!!! First-semester Thermodynamics. Get a book from the library, look it up.

And jet engine manufacturers DON'T use steel in the hot sections of their engines BECAUSE IT'D MELT!!!

BUY A CLUE!!!

And I was always thinking that the official theorists deny the existence of pools of molten metal...
wcelliott
QUOTE
And I was always thinking that the official theorists deny the existence of pools of molten metal...


You mean the molten lead from the Uninterruptable Power Supplies' lead-acid batteries?
einsteen
There was a post about that

http://11-settembre.blogspot.com/2007/02/u...or-of-wtc2.html
Trippy
QUOTE (Chainsaw,+Aug 27 2007, 12:49 PM)
The method of oxidation is critical to flame temperatures, not only does jet fuel com bust but it forms super heated steam as part of that combustion process, that can itself react as an oxygen source with reactive metals releasing hydrogen and that can go on where ever the conditions exist for entrapment of the super heated steam.

Minor point, and I think I've pointed this out before.

It's not super heated steam that's produced by standard combustion reactions, it's water in the gas phase, or water vapour.

Superheated steam is something different (more or less).

Steam (generally) refers to condensed water droplets suspended in the air, where as what's produced by the combustion of hydrocarbons is water vapour, or water in the gas phase. It's a subtle difference, but it's also a very important distinction to make.
Chainsaw,
QUOTE (Trippy+Aug 27 2007, 11:18 AM)
Minor point, and I think I've pointed this out before.

It's not super heated steam that's produced by standard combustion reactions, it's water in the gas phase, or water vapour.

Superheated steam is something different (more or less).

Steam (generally) refers to condensed water droplets suspended in the air, where as what's produced by the combustion of hydrocarbons is water vapour, or water in the gas phase. It's a subtle difference, but it's also a very important distinction to make.

Yes you did bring it up before, but H2O in the gas phase is still H2O, and it is only when H2O is heated to at or near the gas phase that it effects steel super heated steam can only be produced by compression of the H2O gas Trippy, because when the gas is released from a compressed state, it reverts to water in the gas phase.

So your basically comparing apples to apples, were talking about the same reaction because gas phase H2O is what causes the reaction in the first place.
That or actual steam from the cooling water phase H2O encountering steel heated to near 900c.
A buoyant hydrogen flame will create water in the gas phase at the steel gas interface causing a sustained reaction until the gas phase water and hydrogen are vented.
However once steel oxidation has started as long as temperatures can be maintained by air flow over the steel the steel will continue to Oxidize.
I am simply using steam and super heated steam to put it in laymens terms!
Chainsaw,
QUOTE (wcelliott+Aug 27 2007, 05:12 AM)

Agreed.

My point was that jet engines, burning jet fuel as they normally do, create temperatures in their combustion chambers that would exceed steel's maximum working temperature. It would be more accurate to say that a jet engine made with steel components in the combustion chamber would fail due to the steel's inability to maintain structural integrity at elevated temperatures, but if somebody's so stupid that I need to point this out, then that explanation would probably just go over their head anyway.

Also, I'd still like the point I just raised to be considered further, about how much compression (and therefore temperature of combustion increase) one should expect from air being accelerated by aircraft debris going 500mph.

I'm not sure how to go about calculating the pressure increase, other than to assign random coefficients of drag to random-sized chunks of debris and assuming that the drag energy is compressing the air in front of it, inferring a delta-pressure*volume from the loss of kinetic energy of the debris. Then, the increased pressure combustion yields an increased combustion temperature.

Can anyone think of a more elegant approach? This one gives me a headache just thinking about it.

Actually the tests in actual jet engines pointed to H2O vapor phase combustion of steel components, in the early jet engines leading to Compressor failure, as the most likely cause of flame out and lockup in jet engines primarily in the Messerschmidt of World War 2.
The early jets were known to actually explode do to lockup of the compressors.
Daru
The only thing people have to do is, get some kerosene, spray it on and all over a steel structure and set it on fire. See what will happen. wink.gif

(but I can tell you, nothing serious will happen to the structure, it will be some fire, yes, but no collapse and no total destruction in CD style)

But did you know that there was no sprinkler in the Deutsche Bank Building and workers told officials they had been stripping asbestos from beams, and the fire spread quickly through gaps and holes in the structure. blink.gif
adoucette
QUOTE (Daru+Aug 27 2007, 10:48 AM)
The only thing people have to do is, get some kerosene, spray it on and all over a steel structure and set it on fire. See what will happen. wink.gif

(but I can tell you, nothing serious will happen to the structure, it will be some fire, yes, but no collapse and no total destruction in CD style)


Why do you keep acting like ignorance is a virtue?

The kerosene's heat impact on the structure was relatively little, the MAIN fire damage was caused by the FLAMABLE CONTENTS of the building, ~ 128,000 lbs per floor.

The kerosene's main contribution was to start widespread fires on multiple floors, thus increasing significantly the RATE of heat release.

The multiple floor fires released GIGAJOULES of energy into the structure.

WHY, if you think NOTHING would happen from fire to the structure, do you think they spray the whole friggin structure with costly SFRM?

Arthur
Chainsaw,
QUOTE (Daru+Aug 27 2007, 02:48 PM)
The only thing people have to do is, get some kerosene, spray it on and all over a steel structure and set it on fire. See what will happen. wink.gif

(but I can tell you, nothing serious will happen to the structure, it will be some fire, yes, but no collapse and no total destruction in CD style)

But did you know that there was no sprinkler in the Deutsche Bank Building and workers told officials they had been stripping asbestos from beams, and the fire spread quickly through gaps and holes in the structure. blink.gif

Hey Daru, try entrapping the hot exhaust gasses where they accumulate next to a thin steel structure like OH say a floor pan, so that they heat up. That will definitely change the reaction experienced!
Also adoucette is right your ignoring the other combustibles, and chemical reactions!
It shows just how ignorant of reality, your claims actually are!
OneWhiteEye
QUOTE (einsteen+Aug 27 2007, 08:38 AM)
The colour splitting RGB is a little bit beyond me. Didn't you also say in the past that the human eye is needed to judge the image ?

I think the best way to obtain curves from the latter parts where motion is obvious and quick is through the eye. Automated methods would produce noisier data if they would work, but there are too many instances where they really won't work at all without a lot of manual intervention. So, eyeballing will be much easier and faster for getting the gross curve.

The automated methods are useful for the smaller, initial displacements. One method looks at color transition over time (before obvious motion), another tracks average spatiotemporal location of pixel-sized features (at the onset of motion that is too small to get good discrete pixel measurements). Together, the three methods span the full time period with overlap and redundancy.

The manual eyeball method should be done over the whole range, starting with position well before the collapse, then a point that appears to just precede collapse (Tzero guess), and subsequently point density that seems appropriate. If enough locations of a 'rigid body' are done in this fashion, it will sharpen the Tzero estimation and data values. Best if it were done by a variety of people. Then, applying the two automated methods will increase the early resolution even farther.

Right now my concern is in establishing early rotation since it has a tremendous impact on the fine vertical measurements. It seems easier to establish the rotation first and then choose suitable locations for vertical measurements and correct for rotation effects.
David B. Benson
QUOTE (einsteen+Aug 27 2007, 02:43 AM)
And I was always thinking that the official theorists deny the existence of pools of molten metal...

I don't know what you mean by official theorists, but I have yet to see any credible report or evidence for pools of molten metal.

Stories grow in the telling, like the big fish that got away...
555Joshua
QUOTE (einsteen+Aug 27 2007, 04:43 AM)
And I was always thinking that the official theorists deny the existence of pools of molten metal...

Jet fuel cannot burn hot enough to create mass quantities of melted steel. However, it can burn hot enough to soften beams and and cause a building to collapse. There is no evidence of any streams of metal.
David B. Benson
QUOTE (OneWhiteEye+Aug 27 2007, 09:40 AM)
I think the best way to obtain curves from the latter parts where motion is obvious and quick is through the eye. Automated methods would produce noisier data if they would work, but there are too many instances where they really won't work at all without a lot of manual intervention. So, eyeballing will be much easier and faster for getting the gross curve.

The automated methods are useful for the smaller, initial displacements. One method looks at color transition over time (before obvious motion), another tracks average spatiotemporal location of pixel-sized features (at the onset of motion that is too small to get good discrete pixel measurements). Together, the three methods span the full time period with overlap and redundancy.

The manual eyeball method should be done over the whole range, starting with position well before the collapse, then a point that appears to just precede collapse (Tzero guess), and subsequently point density that seems appropriate. If enough locations of a 'rigid body' are done in this fashion, it will sharpen the Tzero estimation and data values. Best if it were done by a variety of people. Then, applying the two automated methods will increase the early resolution even farther.

Right now my concern is in establishing early rotation since it has a tremendous impact on the fine vertical measurements. It seems easier to establish the rotation first and then choose suitable locations for vertical measurements and correct for rotation effects.

For WTC 1 the tilting is probably not significant from the standpoint of making vertical measurements. For example, a tilt of one degree of arc of the top block means that the antenna tower has descended about 0.55 meters. So measuring the descent can be used to determine the tilt angle for at least the first 0.8 seconds, before the north wall breaks.

The notion of a t_0 is artificial, albeit useful. What is very interesting is the descent (tilt) starting at the time that floors 98 and 97 expressed smoke and actual flames. This occurs about two seconds before NIST's t_0, and measuring this descent for that time and, say, the following two seconds would provide some useful data regarding collapse initiation hypotheses.
Trippy
QUOTE (Chainsaw,+Aug 28 2007, 01:10 AM)
Yes you did bring it up before, but H2O in the gas phase is still H2O, and it is only when H2O is heated to at or near the gas phase that it effects steel super heated steam can only be produced by compression of the H2O gas Trippy, because when the gas is released from a compressed state, it reverts to water in the gas phase.

So your basically comparing apples to apples, were talking about the same reaction because gas phase H2O is what causes the reaction in the first place.
That or actual steam from the cooling water phase H2O encountering steel heated to near 900c.
A buoyant hydrogen flame will create water in the gas phase at the steel gas interface causing a sustained reaction until the gas phase water and hydrogen are vented.
However once steel oxidation has started as long as temperatures can be maintained by air flow over the steel the steel will continue to Oxidize.
I am simply using steam and super heated steam to put it in laymens terms!

I get all that, I really do, but none of that changes the fact that the usage of the 'Steam' or 'super heated steam' when talking about water vapour is a misnomer, and inaccurate.

I know it's a bit of... The word I'm searching for escapes me for some reason, I want to say pedantic, but it's more about accuracy.

Steam is a condensate, and requires cooling to form (This includes reducing pressure, which causes cooling), but what you're dealing with is water vapour (and generally talking about). I get that you're trying to put it in laymans terms, but you really would be better off talking about water vapour rather then steam. Most people should be able to figure out what you're talking about, and those that can't should ask or look it up.
Trippy
http://www.libertypost.org/cgi-bin/readart...183119&Disp=107

http://screwloosechange.blogspot.com/2007/...hot-enough.html

One of the things that I find amusing is this: Okay, sure, there may or may not have been molten metal (steel?) present at ground zero after the collapse, but how, precisely is that relevant to the collapse itself again?

Are people really assming that the molten metal must have been present before the collapse?

Come on, get real, confinement, insulation and reburning are some of the easiest ways of cranking up the temperature of a fire. Have any of the CDiots stopped to consider the fact that maybe the presence of molten metal after the collapse could have been solely the result of the collapse, and the fires afterwards and that the hours to weeks between the collapse occuring and people finding these things is plenty of time for such a mechanism to occur.

Doubly so when you take into account how much of the kinetic energy would have been converted into heat energy.
Trippy
My apologies if this has already been posted, but I thought it was pretty fricking amaizng, and seems to address some of the things being discussed here.

Edit:

Of course, it helps if I include the actual link.
http://www.youtube.com/watch?v=gH02Eh44yUg
newton
QUOTE (Trippy+Aug 27 2007, 11:24 PM)
http://www.libertypost.org/cgi-bin/readart...183119&Disp=107

http://screwloosechange.blogspot.com/2007/...hot-enough.html

One of the things that I find amusing is this: Okay, sure, there may or may not have been molten metal (steel?) present at ground zero after the collapse, but how, precisely is that relevant to the collapse itself again?

Are people really assming that the molten metal must have been present before the collapse?

Come on, get real, confinement, insulation and reburning are some of the easiest ways of cranking up the temperature of a fire. Have any of the CDiots stopped to consider the fact that maybe the presence of molten metal after the collapse could have been solely the result of the collapse, and the fires afterwards and that the hours to weeks between the collapse occuring and people finding these things is plenty of time for such a mechanism to occur.

Doubly so when you take into account how much of the kinetic energy would have been converted into heat energy.

this "CDidiot" has considered that the extreme temperature of the debris pile is all/mostly underneath. and yet, the fire was at the top of the pile!

oh. my. lions, tigers and bears.

this CDidiot has noticed that the pile was hottest immediately after the collapse, and could not be put out with water, and so pyrocool was used..

oh. my.

this CDidiot has noticed that childish insults are now a requirement of all OCT posts.

http://911research.wtc7.net/cache/wtc/evid...ubblefires.html

people often abandon their stance and shrug shyte off when being heavily derided. others just think it's a pathetic tactic.

that's a report 12 weeks after the attacks.

the fire was up top, and was rather out of fuel at the time of collapse. the underground inferno was most likely the result of a different energy source. there were 70 storeys of steel and concrete between the fires and the ground.

the OCT wants chaos to conform to some bizarre orwellian regimen. just like that sentence.
David B. Benson
QUOTE (Trippy+Aug 27 2007, 04:24 PM)
Doubly so when you take into account how much of the kinetic energy would have been converted into heat energy.

Most of the energy available in/at Ground Zero was chemical energy from the buildings' flammable contents.
Trippy
QUOTE (David B. Benson+Aug 28 2007, 12:53 PM)
Most of the energy available in/at Ground Zero was chemical energy from the buildings' flammable contents.

I beg to differ.
The GPE of the floors had to be converted into something.
Some of it was used up in the compaction of the floors/during the collapse.
Some of it was used up to pulverize the concrete.
But there was a large portion of it that would have been converted into heat energy (Some of which invariably would have caused the ignition of flammable materials).
Trippy
I suspect that arguing this with you is going to be an exercise in futility, however.

QUOTE (newton+Aug 28 2007, 12:40 PM)
this "CDidiot" has considered that the extreme temperature of the debris pile is all/mostly underneath.  and yet, the fire was at the top of the pile!

oh. my.  lions, tigers and bears.


Hmmm, let me see. The floors contained the combustible materials. According to the official explanation the floors went first, then the walls came down, so that would put the fuel for the fire at the bottom of the pile, and the original burning floors somewhere near the middle.

Wrong again, Oh my.

QUOTE (newton+Aug 28 2007, 12:40 PM)
this CDidiot has noticed that the pile was hottest immediately after the collapse, and could not be put out with water, and so pyrocool was used..

oh.  my.


As would be expected, oh my. Radiative heat has a cooling effect KE->Heat energy, and is radiated away causing cooling, oh my. Fires run out of fuel as they burn it, and cool, oh my.

Wrong again, oh my.

QUOTE (newton+Aug 28 2007, 12:40 PM)
this CDidiot has noticed that childish insults are now a requirement of all OCT posts.


That's funny, because my experience tells me that CD'ers are usually the first to refer to 'OCT'ers' as being evil mindless puppets.

QUOTE (newton+Aug 28 2007, 12:40 PM)
http://911research.wtc7.net/cache/wtc/evid...ubblefires.html

people often abandon their stance and shrug shyte off when being heavily derided.  others just think it's a pathetic tactic.


I have no idea what you're getting at here, again, it's been my experience that it's usually the CD'ers that start throwing out insults when they're cornered, an experience that has been confirmed in this thread.

QUOTE (newton+Aug 28 2007, 12:40 PM)
that's a report 12 weeks after the attacks.

the fire was up top, and was rather out of fuel at the time of collapse.  the underground inferno was most likely the result of a different energy source.  there were 70 storeys of steel and concrete between the fires and the ground.


Did you bother to read that report? Or did you just ignore the part at the end where it talks about how the fires were allowed to burn for 17 days before anything serious was done about fighting them because it was being treated as a rescue operation. The fact that they used Pyrocool FEF is largely meaningless, apart from the fact that it says that they wanted to fight the fires in the most effective general purpose way they could.

QUOTE (newton+Aug 28 2007, 12:40 PM)
the OCT wants chaos to conform to some bizarre orwellian regimen.  just like that sentence.


Meaningless paranoid delusional drivel. Did you forget to take your antipsychotics today?

newton
QUOTE (Trippy+Aug 28 2007, 01:37 AM)
Meaningless paranoid delusional drivel.  Did you forget to take your antipsychotics today?

gee. a reference to mental health problems.

i'm so surprised you didn't deride me.

so, as to your first supposition that we have an exercise in futility, i'll have to agree, as you have already decided the truth, and so have i.

QUOTE
*OFF TOPIC!!!!!*

According to Sir Isaac Newton, the mark of the Beast is three crosses.

*OFF TOPIC!!!!!*
555Joshua
QUOTE (Trippy+Aug 27 2007, 06:24 PM)
One of the things that I find amusing is this: Okay, sure, there may or may not have been molten metal (steel?) present at ground zero after the collapse, but how, precisely is that relevant to the collapse itself again?

It goes back to one or two forums ago (yes, they just won't give it up!!!) where they mor@ns argue that jet fuel could not have hosted an explosion that resulted in pouring rivers of melted steel they showed in "authentic" pictures they got off nut job sites.
Trippy
There is some footage, I'm not going to comment on validity, that appears to show molten metal in one corner of one building, however, IIRC, its in the corner that Arthur said that NIST had found evidence of flowing molten metal, or it might have been metal fires, which would seem to go hand in hand with molten metal, it's also in the corner of the building where, from an emperical perspective, I would have expected to be a hotspot.

Sorry, this post was meant to be in reply to Joshua's post - i'm sitting outside in the freezing cold, and the pitch black, with my laptop trying to observe a lunar eclipse (but it's clouded over).
Bryn Richards
I am happy with the progress which groups like popular mechanics have made, regarding 9/11, but I wish they would also investigate 7/7 too, because my Truther friend has not stopped going on about it, after he switched from 9/11 conspiracies, in the wake of the debunkings. He's also a bit crazy about the whole WTC 7 business nowadays too.

He made the switch, because they are less debunked than the twin towers, pentagon and the flight 93 crash are. Conspiracy theories love a vacuum, after all...

Does anyone know of a mass-debunking of 7/7 conspiracies, anywhere on the net? (Similar to the popular mechanic debunking of 9/11)
NEU-FONZE
Trippy:

A simple calculation of the conversion of the Twin Tower's PE to KE and then to HEAT shows that the PE was NOT the source of heat in the rubble pile:

PE of two towers = 2 x 10^12 J

Let's assume ALL the PE -> KE so KE = 2 x 10^12 J

Let's also assume ALL the KE -> HEAT

HEAT = Mass (kg) x Heat Capacity (J/kg. deg C) x Delta (T)

The mass of the two towers was ~ 1,000,000 tonnes

A reasonable average heat capacity for the materials in the rubble pile would be ~ 500 J/kg.deg C, hence

Delta(T) = 2 x 10^12 / [10^9 x 500] = 4 deg C

This shows that the heating of the rubble pile must have been mainly from the release of CHEMICAL ENERGY. I would estimate from the mass of combustibles that the chemical energy available in the rubble pile was at least 10^14 J or 50 times the PE stored in the towers.

einsteen
Interesting Neu-Fonze, could that amount of energy be explained by combustion processes on the first initial floors ? I don't believe that during that fast collapse the whole rubble pile could heat up, although the calculation doesn't say at which time the temperature is measured, if it is homogeneous etc. The temperature after the collapse would be very interesting.
wcelliott
QUOTE
The temperature after the collapse would be very interesting.


There's that classic physics problem where you calculate the temperature difference between the water at Niagra Falls, before and after, and the temperature rises a surprisingly small amount from the fall, on the order of a degree or so. Nothing that would start a fire.

The extreme temperatures found in the rubble pile can better be explained by comparing the rubble pile to a foundry, where the heat released from burning fuel is confined by insulating materials, but airflow is relatively unrestricted. That's how people used to make glass and melt iron.
NEU-FONZE
Einsteen:

I believe about 200 tonnes of solid material, such as paper, books, plastics and office furniture, was set on fire by the burning jet fuel spilled in each Twin Tower. Interestingly, however, most of the available jet fuel was probably consumed within 4 minutes of the aircraft impacts. Nevertheless, by this time, the fires had attained a heat energy release rate of about 1 gigawatt and were propagating by the combustion of cellulose and plastic-based solid “fuels” derived from live load materials within WTC 1 & 2.

NIST suggest that the initial 1 gigawatt heat release rate associated with the fires had fallen to about 0.5 gigawatts at the time of the collapse of each Tower. From these data I would estimate that about 2000 gigajoules of heat energy was released in each Tower prior to collapse, of which about 200 GJ was from liquid fuel and 1800 GJ was derived from solid fuel.

If we assume that this solid fuel had an effective heat of combustion of 20 MJ/kg I would conclude that the pre-collapse consumption of solid combustible material in each Tower was about 90 tonnes, out of a possible 200 tonnes, leaving about 110 tonnes of un-burnt material.

I would therefore assume that when each Tower collapsed, over 100 tonnes of burning material and smoldering “embers” at 500 - 700° C, fell into the rubble pile.

There were also fires burning in the basements of the towers at the time of their collapse. I therefore see no problem in getting a real furnace raging at least in some pockets within the rubble pile.

I also think the idea that the PATH subway tunnels may have acted like giant tuyeres and fed air into the heart of the fires is quite possible.
einsteen
Ok, that's all fine of course. Let me explain precisely the problem that I have with the gravitational collapse, you asked it at JREF. The theory is that the removement of the supporting structure between two floors, say at floor 100 leads to a total global collapse, stepwise. Let's assume that all E1 values are equal and all masses are equal. the block that drops on the remaining structure cannot only destroy the story below. I understand that there must be a small crush up and crush down resulting in a layer that protects the rest of the upper floors from being damaged. That's fine.
But then ? The static load is largest at the bottom in this model, then the dynamic load is added to it. I don't believe that the observed behaviour is consistent with gravitational collapse, and I'm very sure about that. If the whole top block drops for example 10 stories then it has enough kinetic energy to destroy the whole structure below, the whole structure then falls down like an implosion from the bottom. When the strength of the building increases (lineairly for example) with the distance from the top then the observed stepwise behaviour makes sense for me. But that leads to other 'problems' because with a few integrals you can prove that the energy will be absorbed by the building when you take into account the initial motion of the top block.
OneWhiteEye
QUOTE (David B. Benson+Aug 27 2007, 06:16 PM)
For WTC 1 the tilting is probably not significant from the standpoint of making vertical measurements.  For example, a tilt of one degree of arc of the top block means that the antenna tower has descended about 0.55 meters.  So measuring the descent can be used to determine the tilt angle for at least the first 0.8 seconds, before the north wall breaks.

The notion of a t_0 is artificial, albeit useful. What is very interesting is the descent (tilt) starting at the time that floors 98 and 97 expressed smoke and actual flames.  This occurs about two seconds before NIST's t_0, and measuring this descent for that time and, say, the following two seconds would provide some useful data regarding collapse initiation hypotheses.

I see what you're saying, and I'm going to attend to things in a different order because you may not need the level of detail I'll eventually have.

As I mentioned, there are three types of methods I'm using to extract numeric data, each with an associated resolution and applicable timeline range. They could loosely be categorized as fine, medium and coarse measurements:
  • Slow transition of pixel-sized features across single pixel distances (earliest motion)
  • Faster transition of pixel-sized features across several pixels (first obvious vertical motion on video - the elbow of the curve)
  • Manual digitizing of multi-pixel features from frame sequences and einsteen images (entire sequence)

The third method, while weak in the early timeline, may be sufficient for what you describe. Rotation doesn't enter in to making that measurement. I can produce several datasets of that type from at least 3 videos in a day or two; no need for you to wait for other stuff to be complete. The bigger effort, in that case, is obtaining reliable scaling factors for the conversion from pixels to meters. The data will be in pixels and I'll provide the best conversion numbers I can get get at this time - you take responsibility for converting to meters!


Now a long-winded explanation of the problem of rotation.

Rotation is an impediment for the first two methods, especially the first which attempts to map the motion of a feature through pairs of adjacent pixels. This method could yield position resolution of 0.05 meters (not that I'm claiming or guaranteeing that). A tilt of one degree in this context is a whale flopping in a minnow pond.

When lateral translation occurs concurrently with vertical translation of a similar order, the problem becomes 2D in the (x,y) plane. This is a minor hassle but can't be ignored. If lateral motion (x) can be independently measured first - and in this case it can - a linear correction can be calculated and the vertical motion can then be processed in 1D as opposed to simultaneously solving both dimensions in a discrete space with a 3x3 mesh.

But the biggest problem with rotation is how small amounts can radically change the appearance of a feature compared to translation. Simple and extreme example: take a hand mirror outside, hold it at arm's length and adjust the orientation so the sun is reflected directly into your eye. Lower the mirror a couple of millimeters while preserving the orientation; chances are your retina is still on fire. Now tilt it so one edge drops the same amount, the intensity drops off substantially.

The antenna is a 3D object with components having different surface properties and appendages. That can be a good thing; the tiny white 'orbs' show up in one video as gray-brown crosshairs, two on each side. Generally, however, a small rotation can change pixel brightness quite a bit without (hypothetically) any accompanying translation. The distribution of smoke in the scene influences the incident light (ambient and diffuse) and the irregular antenna surface, with its specular properties, could be expected to exhibit unpredictable variations of reflectivity under rotation. Not so with translation.

The tapering of the antenna alone is enough to drive me nuts! Then there's the deviation of the frame from true vertical, but at least that's static over time and changes insignificantly over small pixel regions.
carterelliott
QUOTE
the whole structure then falls down like an implosion from the bottom


The part that you're missing is that not all of the force applied at floor X will be transmitted to floor X-1, only the force that the structure below floor X can sustain will be transmitted through the structure. In other words, if the structure holding up floor X-1 can, at most, support 100,000tons (picking a number from mid-air), and the force applied to floor X-1 is 500,000tons, then only 100,000tons is transmitted to the structure, the other 400,000tons can't be transmitted via the structure, so goes into acceleration of the material making up floor X (and destroying anything that can't withstand the forces involved).

This is the key to understanding why the floors collapse one-by-one, from the top down. The intact structure below the crush zone is overloaded, but still only by an amount that the structure can sustain. It's outside its normal design limits but the forces have an upper limit which is determined by the yield limit of the structure in the crush zone.

(Maybe after the coffee has soaked in, I'll be able to state this explanation in clearer language.)
einsteen
The force that is working on story i in order to get it compacted can only be provided by the reaction force provided by story i+1 (one lower). Since there is absolutely no movement of the stories/floors below the implication is that the whole underlying structure is still in the elastic phase, not much energy needs to be transferred in the case that the value F'(0) is extremely large, which is the case. But it should move a little bit in order to provide the reaction force. Assume a model in which we have the top block and in a thought experiment and we set all masses of the floors below equal to zero. In this model the forces will balance each other out and the energy can be provided. I have to say that it is still something for which I have had no time and mood to work out completely. You are right that the masses of the floors below are very inert and that that may play a role in the behavior but then one should set up a very complex set of differential equations. these are then a couple of masses connected by forces of the form F=F(|y1-y2|), good luck to solve it. No I am still not convinced at all that this closed system called building is able to behave in that way (only taking into account mechanical energy) but we are never too old to learn, one day I probably will say. Yes, now I see, stupid, I really had a big blind spot and then everything is fine.
Trippy
QUOTE (NEU-FONZE+Aug 29 2007, 12:11 AM)
Trippy:

A simple calculation of the conversion of the Twin Tower's PE to KE and then to HEAT shows that the PE was NOT the source of heat in the rubble pile:

PE of two towers = 2 x 10^12 J

Let's assume ALL the PE -> KE so KE = 2 x 10^12 J

Let's also assume ALL the KE -> HEAT

HEAT = Mass (kg) x Heat Capacity (J/kg. deg C) x Delta (T)

The mass of the two towers was ~ 1,000,000 tonnes

A reasonable average heat capacity for the materials in the rubble pile would be ~ 500 J/kg.deg C, hence

Delta(T) = 2 x 10^12 / [10^9 x 500]  = 4 deg C

This shows that the heating of the rubble pile must have been mainly from the release of CHEMICAL ENERGY. I would estimate from the mass of combustibles that the chemical energy available in the rubble pile was at least 10^14 J or 50 times the PE stored in the towers.

Eh, whatever, I got the impression from... I think it was greenings report that there was more to it then that, also I notive that you're calculations assume that the heat was distributed evenly throughout the entire falling mass, which may or may not be an accurate assumption.

Besides, my point was that I was offering up an energy source that was being ignored by the CD'ers, nothing more.

Edit: Also, please take the time to notice that NOWHERE did I attribute ALL of the heat energy as being from the collapse of the towers, I simply stated that it was one of the sources, note that I also said

QUOTE (Trippy+Aug 28 2007,11:24 AM )
Come on, get real, confinement, insulation and reburning are some of the easiest ways of cranking up the temperature of a fire.


A view that was echoed by WCElliot with his reference to furnacing, and furnace effects.
David B. Benson
QUOTE (OneWhiteEye+Aug 28 2007, 09:24 AM)
The bigger effort, in that case, is obtaining reliable scaling factors for the conversion from pixels to meters. The data will be in pixels and I'll provide the best conversion numbers I can get get at this time - you take responsibility for converting to meters!

Alas, I'll have to rely on your conversion numbers. Poster einsteen suggested a technique which seems robust: count the number of pixels from the top of a window to the top of the window above (below).

If you meant I should do the arithmetic, sure thing!
shagster
QUOTE (einsteen+Aug 28 2007, 03:46 PM)
If the whole top block drops for example 10 stories then it has enough kinetic energy to destroy the whole structure below, the whole structure then falls down like an implosion from the bottom.


That's possible if there was a way of conveying the energy of the falling mass to the rest of the tower below the front within a short time interval. How would that be done in the WTC towers where columns were tilted and laterally offset from one another through the collapse front? That causes connections to fail and columns to buckle in the region of the front before a large amount of energy can be conveyed far away from the front.

Most of the falling mass that accumulated at the front was intercepted by the floor slabs between the core and perimeter. The lightweight trusses and their connections failed before the columns did, since the columns had a much higher axial compressive strength than the strength of the trusses or connections.

Even in a situation of perfect axial strikes through the collapse front, which doesn't occur in the real world, buckling during severe overloading of columns and fracture of trusses and their connections in the region of the front would somehow have to be prevented in order to convey a large fraction of energy of the falling mass far away from the front.

OneWhiteEye
QUOTE (David B. Benson+Aug 28 2007, 10:04 PM)

If you meant I should do the arithmetic, sure thing!


Haha, yes that's what I meant. It's a silly CYA thing. I just want to emphasize that the scaling is derived through different processes. Any consumer of this data should have the original measurements and conversion value on hand. One way to ensure that is to supply only those items. But I could just as easily have fields for both pixel and meter distances or post two datasets - one with pixels the other with meters. Whichever works best for you.

QUOTE
Poster einsteen suggested a technique which seems robust: count the number of pixels from the top of a window to the top of the window above (below).


Yes, definitely. I need to find better videos!

How tall are the windows in this slice of wall?

user posted image
OneWhiteEye
QUOTE (Trippy+Aug 28 2007, 09:48 PM)
Eh, whatever, I got the impression from...  I think it was greenings report that there was more to it then that....

Where have I seen this before? Oh yeah, over at JREF. It was funnier over there, though.
NEU-FONZE
Maybe I should try reading greening's report.....
einsteen
The best movie that I currently have is this one

http://youthfulindiscretions.com/vid/911/w...emolition-4.avi

(check also the other ones in that index) And that is the one I've used to generate the images, it has the best resolution but no sound. There is a smaller movie which has sound (I believe also a different frame-rate), there you hear a chopper, I also don't think that sound is genuine because you hear no sound at all during the collapse and the sound is tremendous (in other collapse videos)

This is a bizarre video, about 10 seconds before initiation the camera shakes, a possible debunk is that someone hit it at that time (although it must be on that tripod for a while) but at that moment also some debris is ejected from the open zone in the building, probably it could be that initiation already started there, but the antenna still didn't start dropping. During the collapse the camera is not really moving but when the first debris hits the ground (the ejected panels originating from the 14 story top block) a smaller movement of the camera could be observed, This movement is consistent with a free fall of that debris in air and gives about the same time as the NIST gave. The first movement of the camera (10 seconds before) has a bigger amplitude than when the debris hits the ground which doesn't make sense for me, someone could have hit hit, but then why does a piece of debris leave the building ?

I'm not sure what the distance between (the center of) two floors is, 3.7m is mentioned, 3.8m also. Depends on the base on which the towers were standing
einsteen
QUOTE (NEU-FONZE+Aug 29 2007, 01:20 PM)
Maybe I should try reading greening's report.....

Or learn something from Apollo20.. biggrin.gif

ps. did you recently post at the LC'ers ?
wcelliott
QUOTE
This is a bizarre video, about 10 seconds before initiation the camera shakes, a possible debunk is that someone hit it at that time (although it must be on that tripod for a while)


If you've ever done much camera work, you'll know that a camera's natural state is in motion and out-of-focus. You have to exert Jedi-like mind control over the things to get them steady and keep them focused.

One possible explanation was that when the guy first set up the camera and started filming, he was still close to it in case it needed extra tweeking to get it working right, and when he saw the puff of whatever, it startled him. Or, maybe he was stepping away from the tripod and it snagged his foot as he went past.

If you're trying to link the camera shake to the puff-event (as he's undoubtedly hoping you will) don't forget to factor-in the speed of sound and the distance between the camera and the event. He probably overlooked that when he manipulated the video. People routinely forget that and will add sound effects that happen concurrent with the imagery, a dead giveaway that the footage has been tampered with.
John A
Here's a question that I've asked on many forums, but have not received an answer...

How does this fit into the equation? If these dampers are strong enough to correct a 3ft from center sway...How would they affect the collapse?
Thanks

QUOTE
Damping the sway
Each of the Twin Towers had 11,000 built-in shock absorbers to lessen the buildings' sway in strong wind.

As sturdy as these towers would be, Robertson and Skilling knew they would still be flexible in high winds. Indeed, they designed them to be so. But they realized the swaying effect, especially in strong gusts, might bother tenants high in the building. So they fashioned yet another innovation, a state-of-the-art damping system. Like door closers or car shocks, the dampers absorbed the wind's punch, easing the towers one way or the other so smoothly that office workers hardly noticed the movement.
The dampers were made of visco-elastic material. "These are materials that are partially viscous, that is, partially flowable like oil, and also elastic, which means they act somewhat like steel, in that if you strain them they return to their original shape," Robertson says. "So the material is in between those two materials—it's not like oil, it's not like steel, it's visco-elastic."
Robertson's crew placed the dampers, 11,000 of them in each building, between the bottom of the floor trusses and the columns—two parts of the building that tended to move with respect to each other when the edifice swayed. When it did so, those two parts would shear the visco-elastic dampers. This shearing caused the material to heat up, and that heat was transferred to the building. "So we take the energy of the wind, and we heat the building with it," Robertson says with a note of pride in his voice.

http://www.pbs.org/wgbh/nova/wtc/innovation.html
adoucette
QUOTE (John A+Aug 29 2007, 09:58 AM)
Here's a question that I've asked on many forums, but have not received an answer...

How does this fit into the equation? If these dampers are strong enough to correct a 3ft from center sway...How would they affect the collapse?
Thanks


Minimal at best.

They joined at the bottom of the truss, so for them to absorb any energy in the vertical direction, the truss seat above it would essentially have had to already have failed.

http://i117.photobucket.com/albums/o72/ard...te/trusscon.jpg

User posted image

They clearly were not designed to handle vertical loads and so would have then immediately failed, with their contribution being roughly the amount of energy needed to shear ~80 of these visco-elastic dampers per floor (1 per tree).

Arthur

einsteen
I think you should first watch the movie wcelliot. I don’t believe someone was near the camera, it was steady on a tripod. If someone was near the camera he or she would zoom in during the collapse. And who is hoping I will ? This is (as far as I know) a raw footage and nothing has been cut ‘n pasted. The speed of sound is irrelevant as I said that the movie doesn’t contain audio. I don’t say there is a direct relation with that piece of ejected debris and the shaking, maybe someone saw or heard something and hit that thing, or there is an other cause. The only difference between the camera position before and after the shaking is a few pixels, nothing has been changed manually in the setting, no zoom in, no rotation, no colour change. I also don’t believe that piece of debris has been added to the movie, I’ve seen it often, I’ve seen it frame by frame. No I’m not the kind of person checking plane videos and looking for compression artifacts or a green flame in wtc7 (ps I debunked the no-plane theory using two different movies with the same frame extraction method, posted it at LC because I’m sick of that) but this is a very interesting video.
adoucette
QUOTE (einsteen+Aug 29 2007, 09:36 AM)
which doesn't make sense for me, someone could have hit hit, but then why does a piece of debris leave the building ?


But YOU are making a correlation when there is NO INDEPENDENT EVIDENCE to support it.

Arthur
einsteen
I'm not making a correlation, that correlation is there. Don't shoot the messenger...
John A
Thanks Arthur,
Would there be any horizontal affect? Also, what color would these dampers be if they were melting?

Here's another question that no one will answer...

Why was there combustible gas present in the subway before the first plane hit?

http://video.google.com/videoplay?docid=59...earch&plindex=6

In this video, you will see an inspector and a news crew preparing to do a news story on a gas leak. (My opinion) The inspector places his TIF 8800 detector against the grid and the gas is detected. Remember, the subways exploded.
Daru
QUOTE (John A+Aug 29 2007, 03:28 PM)
Would there be any horizontal affect?

Yes. Huge.
NEU-FONZE
I believe the visco-elastic dampers were made with a 3M butyl rubber compound. This would degrade at about 300 deg C and be a useless char by 400 deg C.
einsteen
Ok, I have to be very precise with the words used, correlation is no (direct) causal relation. I can't really remember.

Because when the panels hit the ground I would expect that it is related with the shaking. To say something about the correlation of the first shaking we should for example have a 20 minute video, when there is then movement of those two variables there is a correlation. but let's forgot about the first movement, it is more interesting to assume that there is a relation between the piece of debris that leaves the building and the collapse initiation. I will soon check if there are other wtc1 movies in which something can be found about it , bad thing is that there is a lot of crap around.
OneWhiteEye
Thanks for the video link, einsteen. It's from the same source video as the one I've been looking at the hardest, now the third version I've run across. This is the best quality, though.

I've got more to say about this video but I have to run.

Well, before I run:

QUOTE
If you're trying to link the camera shake to the puff-event (as he's undoubtedly hoping you will)...


OK, you got me. I'm the original source for the video, and yes I did jiggle the camera before the collapse to deceive the gullible into believing the collapse was brought on by explosives.
David B. Benson
QUOTE (NEU-FONZE+Aug 29 2007, 06:20 AM)
Maybe I should try reading greening's report.....

biggrin.gif laugh.gif wink.gif
Trippy
QUOTE (NEU-FONZE+Aug 30 2007, 01:20 AM)
Maybe I should try reading greening's report.....

No, that's not what I was saying (or even trying to imply).

Take that partr of my post as meaning "I may have screwed up and remembered some things wrong, attaching more importance to something then I should have" Also known as "I seem to recall this, but I can't recall any specific numbers."

Take the rest of my post as meaning "Yeah, I said that already didn't I?"

Take the antsy in my post as "I've been getting a really hard time from cranks recently,"
wcelliott
QUOTE
The best movie that I currently have is this one


I saw it, and I agree that it's very good.

Is it just my eyesight, or is there a slight angle from vertical visible in the upper section? It appears to be leaning slightly to the left throughout the video.
NEU-FONZE
Arthur:

If a whole bunch of visco-elastic dampers failed through over-heating in the fire-affected zones of the towers do you think the upper sections would have been more flexible and prone to tilting in the presence of asymmetric damage.

I have tried to find data on just how much energy the dampers absorbed - so far without any success - but I would imagine it would be quite significant or why bother to install them....
David B. Benson
Smoldering Fire

Nineteen days ago a nearby grain elevator caught fire and burned to the ground. Four fire departments responded to the initial fire and after about 34 hours, left about 100,000 bushels of smoldering wheat.

Since then, almost daily, the volunteer Rural Fire Department has to take their tanker truck out to the site to dampen the 8 to 10 foot flames which flare up.

Notice the fire is still not out!

Even though most of the time there is neither smoke nor flame...
Trippy
This from Appendix B.1 of the FEMA report .

"The bottom chord of each pair of trusses was attached to the spandrel with visco-elastic dampers that had a slip capacity of 5 kips."

I've also come across this:

User posted image

User posted image

User posted image

From Mahmoodi, P, Robertson, L.E. et others (1987), "Performance of Viscoelastic Dampers in World Trade Center Towers", Dynamic of Structures, Proceedings of the Sessions at Structural Congress'87, Orlando, FL, Aug. 17-20.

Which may have more relevantinformation in it if you can track it down (I thought I had, but it 404'd on me).
Trippy
Table 5.2 of the draft of NCSTAR 1-1A gives the acceptance criteria for the Viscoelastic dampers (3M Brand Vibration Damping Elastomer, #Y-9274) used in WTC 1&2 - note there were actually two different kinds, but as near as I can see at this point, they both used the same materials, just one was a little bigger.

Loss factor (dimensionless) 0.7
Stiffness between 6,000 lbs and 20,000 lbs
Ultimate Strength 40,000 lbs at 75 °F
Fatigue between 5,400 lbs and 22,000 lbs.

When I get home, I'll have a nose around and see if I can find the specs on the material from 3M.
adoucette
.
NEU-FONZE
Trippy:

Yes, I also tried to get the 1987 conference paper by Mahmoodi et al.

I believe it provides real data for the WTC visco-elastic dampers.
adoucette
QUOTE (Daru+Aug 29 2007, 11:51 AM)
Yes. Huge.

No, MINIMAL.

Compared to the strength of the STRUCTURAL connections the ~80 VE dampers per floor would have had minimal impact on either the forces imparted by the impact of the plane (loads applied too fast) or the progression of the collapse (loads applied in wrong direction).

As to the impact on the fire floors, as per Neu's question.

There they may have had a slight impact, since they would have been destroyed over a fairly large area by both the impact and the fires, thus making the already damaged and subsequentyly heated areas slightly more flexible than it would otherwise have been.

If you EXAGGERATE the effect you would perceive the towers would act somewhat like a pair of bobble head dolls

Thus HAD the winds been higher that day, I think it may have possibly had an effect, but my gut feeling is that for the light wind conditions that existed that day, the QUANTIFIABLE impact to the towers would probably not be significant.

Arthur
shagster
QUOTE (einsteen+Aug 29 2007, 01:36 PM)
The best movie that I currently have is this one

http://youthfulindiscretions.com/vid/911/w...emolition-4.avi

That clip is at the start of one of the 911 documentaries I have on DVD but I don't remember which one right now. It's full resolution on the DVD. The DVD shows that video clip with the natural sound of the people on the street with no commentary.

Which debris are you referring to 10 seconds before the collapse? There is at least one person who jumps off the west side of the tower at that time. I would guess that sections of floor may have started to collapse and pushed hot air into people near the windows, which could have been enough for someone to decide to jump.

One of my other DVD documentaries showed the father of someone who was stuck in WTC1 near the aircraft impact region. He was on the phone with his son as the collapse started. The last thing his son said a few seconds before the global collapse was that the ceiling was starting to fall down. The father saw the collapse live on TV just after the line went dead.
OneWhiteEye
QUOTE (shagster+Aug 30 2007, 01:19 AM)
That clip is at the start of one of the 911 documentaries I have on DVD but I don't remember which one right now.  It's full resolution on the DVD.  The DVD shows that video clip with the natural sound of the people on the street with no commentary.
OneWhiteEye
QUOTE (wcelliott+Aug 29 2007, 08:42 PM)
Is it just my eyesight, or is there a slight angle from vertical visible in the upper section?  It appears to be leaning slightly to the left throughout the video.

About a degree for the right edge and about 0.6 degrees for the left. For a particular frame, anyway. Non-orthographic projection. I hope!
OneWhiteEye
QUOTE (adoucette+Aug 29 2007, 11:20 PM)
.

?
einsteen
Thanks Shagster, I got all my vids from the net (and received material) and never odered DVDs. Is it a person ? On my video it looks like a more rounder object. Could you extract some frames?
shagster
QUOTE (einsteen+Aug 30 2007, 08:21 AM)
Thanks Shagster, I got all my vids from the net (and received material) and never odered DVDs. Is it a person ? On my video it looks like a more rounder object. Could you extract some frames?

I will look up which DVD it was. I can try to post some frames. Although I didn't measure the acceleration, the object that falls from the west side falls quickly like a body does. It has the same appearance as other people that jumped.

shagster
QUOTE (OneWhiteEye+Aug 30 2007, 05:35 AM)
Is it WTC - The First 24 Hours?

I have that DVD. That's probably the one but I have to check to make sure.
t0m
Just a quick question regarding the molten orange flow seen, possilbilities of thermate, and results from some samples of debris from the towers, showing signatures indicating accelerants.
Has anyone thought to resample buildings surrounding the WTC tower locations/resample the debris that was cleared?
Chainsaw,
I have finally done it, found a means to cause rapid explosions in the collapses, I tried it in experiments and it works well a little too well.
Take air, at 700c add steam, sprinkle iron dust, aluminum dust or molten aluminum, add carbon. then rapidly compress the result is I am still picking out little pieces of metal sparks, out of my left leg not bad though.
Compressing the air causes overheating of the compounds leading to a steam steel reaction releasing energy the resulting hydrogen and Iron Oxide with carbon releases more energy and ignites some aluminum causing expanding shock waves.
Compressing the air is the key though it allows the air to release considerable heat to the surrounding metals and steam super heating it to H2O in vapor phase, where it reacts with steel dust from broken welds, and beams and crushed concrete reinforcing wire. That triggers further reactions.
The reactions would increase as the buildings picked up speed during the collapses. the faster the compression the more rapid the heating.
I am still working on this but it is incredible the difference just compressing the air makes on the energy values available.

It also caused the formation of little metal spheres from organics, drywall, and aluminum similar to duraluminum, and the steel dust.
Trippy's Ideas on Duraluminum are valid, as are the Ideas about organics it is likely a combination of both lead to the metal spheres.
explosions in the collapse would have been as unavoidable as Aluminum Oxidation was.
I have posted this in hopes it helps in your investigations to know a possible trigger mechanism to explosions and added energy to the collapses.
wcelliott
QUOTE
Just a quick question regarding the molten orange flow seen, possilbilities of thermate, and results from some samples of debris from the towers, showing signatures indicating accelerants.


OK, just some quick answers.

The molten orange flow was probably lead from Uninterruptable Power Supplies on floor 81, which use banks of lead-acid batteries. It *couldn't* have been thermite/thermate, because it has no effect on the metal sheathing of the building, also clearly visible on the same videos showing the flowing lead. If it had been thermite/thermate, it would've melted straight through the material, and it didn't.

No possibility of it being thermate. None. Zero. Give it up.

Regarding signatures of accelerants, there was only one accelerant, it was called "jet fuel", and there was lots of that present, both planes were loaded with it.

Welcome back to reality.
Chainsaw,
QUOTE (t0m+Aug 31 2007, 02:04 PM)
Just a quick question regarding the molten orange flow seen, possilbilities of thermate, and results from some samples of debris from the towers, showing signatures indicating accelerants.
Has anyone thought to resample buildings surrounding the WTC tower locations/resample the debris that was cleared?

What would sampling the buildings surrounding the twin towers gain you since all the compounds would be naturally occurring in the collapses anyway?

Finding evidence of natural occurrences is not evidence of anything but natural occurrences.
adoucette
QUOTE (Chainsaw,+Aug 31 2007, 10:18 AM)
I have finally done it, found a means to cause rapid explosions in the collapses, I tried it in experiments and it works well a little too well.
Take air, at 700c add steam, sprinkle iron dust, aluminum dust or molten aluminum, add carbon. then rapidly compress the result is I am still picking out little pieces of metal sparks, out of my left leg not bad though.
Compressing the air causes overheating of the compounds leading to a steam steel reaction releasing energy the resulting hydrogen and Iron Oxide with carbon releases more energy and ignites some aluminum causing expanding shock waves.

But Chainsaw, the only air that would be near 700C would be on the fire/impact floors.

Since the collapse STARTED at those floors, the collapse rate would not have been fast enough to create any serious over-pressure.

By the time the collapse rate really picks up speed, near the lower floors, you aren't dealing with 700C air anymore or for that matter iron dust or aluminum dust.

Arthur
Chainsaw,
QUOTE (adoucette+Aug 31 2007, 04:44 PM)
But Chainsaw, the only air that would be near 700C would be on the fire/impact floors.

Since the collapse STARTED at those floors, the collapse rate would not have been fast enough to create any serious over-pressure.

By the time the collapse rate really picks up speed, near the lower floors, you aren't dealing with 700C air anymore or for that matter iron dust or aluminum dust.

Arthur

That is what I thought Until I realized that rapid decent would cause heating of carbons and more rapid oxidation of said carbons.

Nist reports the debris at 700-800c when it falls into the rubble pile, it would pick up heat not lose it in the collapses from friction, and faster oxidation and any compression of air would not only intensify the heat, but combustion as well.

As little as 130c compressed sufficiently would cause the reaction of steel and steam by giving heat up to the steel and super heating the H2O, into vapor phase.

Plus steel dust is easy to ignite in air very easy because of increased surface area.

In the early collapse the event would be small but would increase though out the duration of the collapses, until the gravitational energy needed to collapse the air was expended.

Steel dust is just the trigger, carbon, aluminum, and hydrogen are the main reactants.

The main steel dust though would come from the floor pans and the wire in the concrete much of which was never found.
The closer you get to the end of the collapse the more added thermal energy you have.
OneWhiteEye
Regarding motion data from video - I've had some for a while now, but only in pixels. The video from einsteen's link is the best so far by quite a margin. It's pretty easy to measure floor height. The problem is that there is a significant difference between the scaling of horizontal and vertical, indicating the video has been resampled without preserving the aspect ratio OR my methods suck. Either way, it's not acceptable.

The copy has undergone, as a minimum, dump from device to PC, conversion to DivX (from the watermark) then to AVI, with a likely resize thrown in somewhere for 'good measure'. There are compression blocks (DivX is nice but it does let you slaughter the image quality if desired).

I trust the pixel data as being accurate manual digitization of the apparent vertical motion of a small feature through the image plane (with all the cautionary principles of interpretation implied). I can also accept that resampling does not automatically invalidate the picture for motion analysis. However, the notion that I'm too cheap, lazy, or stupid to get my hands on commercially available footage to analyze does not sit well with me so I will be buying at least one DVD in the hopes that the original dump of the video has been faithfully reproduced.

No units of meters from internet videos.
Chainsaw,
QUOTE (adoucette+Aug 31 2007, 04:44 PM)
But Chainsaw, the only air that would be near 700C would be on the fire/impact floors.

Since the collapse STARTED at those floors, the collapse rate would not have been fast enough to create any serious over-pressure.

By the time the collapse rate really picks up speed, near the lower floors, you aren't dealing with 700C air anymore or for that matter iron dust or aluminum dust.

Arthur

Aurthor I just did a sculpture for an expert in ceramic engineering, he refered me to some interesting aspects of coal wastes tailings being used to heat up refractories, by inducing heated sand particles to cause the normally in combustible coal wastes to combust. Simular effect can occur with heated particles in the collapses and the unburned carbons in the buildings.
Since the carbon black would be converted directily by the reaction into Co1-Co2 there would be no smoke just heat.

http://www.power.alstom.com/_eLibrary/pres...pload_51284.pdf
newton
QUOTE (OneWhiteEye+Aug 31 2007, 06:11 PM)
Regarding motion data from video - I've had some for a while now, but only in pixels.  The video from einsteen's link is the best so far by quite a margin.  It's pretty easy to measure floor height.  The problem is that there is a significant difference between the scaling of horizontal and vertical, indicating the video has been resampled without preserving the aspect ratio OR my methods suck.  Either way, it's not acceptable.

The copy has undergone, as a minimum, dump from device to PC, conversion to DivX (from the watermark) then to AVI, with a likely resize thrown in somewhere for 'good measure'.  There are compression blocks (DivX is nice but it does let you slaughter the image quality if desired).

I trust the pixel data as being accurate manual digitization of the apparent vertical motion of a small feature through the image plane (with all the cautionary principles of interpretation implied).  I can also accept that resampling does not automatically invalidate the picture for motion analysis.  However, the notion that I'm too cheap, lazy, or stupid to get my hands on commercially available footage to analyze does not sit well with me so I will be buying at least one DVD in the hopes that the original dump of the video has been faithfully reproduced.

No units of meters from internet videos.

the window width is published by NIST. as well as the width of perimeter columns.

if i remember correctly, it is 22 inches for the windows.

just popping in. no time to research and hand you the data. sorry, but there's some bread crumbs, anyway.

incidentally, i was just discussing einsteen's first attempt at ATS, with his excellent .gif of the dark band on the antenna's descent.

remarkably linear, it is. looks more like a velocity than an acceleration or deceleration, and there is definitely no stutter, indicating a complete absence of momentum transfers in the "crush up/crush down" fantasy.

that post:

http://forum.physorg.com/index.php?showtopic=12383&st=5805#
einsteen
Here a small filedump

http://91.121.24.223/911%20Body%20of%20Evi...%20and%20Video/
http://aldebaran.feld.cvut.cz/~xmyslik/.911/
http://www.positiontoknow.com/S-11/vid/
http://www.911archive.info/video/
http://cleveland.indymedia.org/uploads/2007/01/
http://911research.com/wtc/evidence/videos/docs/

I always bulk download complete sites and then later sort out the videos. I see 'improbable collapse' is also on it, never seen that show. I disagree with the naming, the collapse was not improbable otherwise it wouldn't happen... wink.gif
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