QUOTE (David B. Benson+Apr 5 2008, 08:51 PM)
Houses on the sides of hills in Southern California are notorious for causing landslides. Of course the source of the problem is adding too much water to the soils.
Yes. Rain.
Many developments in southern California over at least the last 30 years have involved considerable reshaping of the earth prior to the first foundation going in. Whatever integrity existed, beyond that provided by previous vegetation, is also lost. In my comment, I'm distinguishing between the factors of:
- soil disruption - road cuts, grading, filling, leveling, etc
- vegetation changes, loss of root mass
- drainage changes
- addition of (and prior loss of) water and attendant effects - mass, lubrication, degaradation of integrity, induced pressure (including osmotic)
as opposed to the weight of the house bearing on earth below, either prior to or during the slide. Not saying the mass of structures above are insignificant, but compared to everything else associated with the presence of a house, maybe not so important. My opinion is the natural terrain of southern California can be classified into mountains, foothills, alluvials/bajada, washes, and dry (or soon to be) lakes. The erosion process is occasionally quite dramatic and discrete (see the Blackhawk slide) but largely gradual. The human earthworks merely accelerate and/or exacerbate the process locally by disrupting the long-term dynamic equilibrium of the landscape, as hundred or thousand year rains do but with different effect.
I see the house in this analogy as the functional equivalent of the antenna mast on the north tower - just along for the ride - where the upper portion of the hillside plays the role of the upper block. In casual observation I've seen plenty of examples of hillsides that have moved as an integral unit, but many more that moved as a non-integral flow, i.e., no 'structure' to crush. While I'd expect landslides and avalanches to be governed by the same basic mechanics, landslides span a spectrum from rock cleavage with minimal mass entrainment to mudslides with mimimal to significant entrainment. Everything from tumbling large blocks to pure fluid flow, as well, which may have some useful correspondence. You'd be hard pressed to find any sort of landslide, however, where the upper portion remains at all intact, other than perhaps some near-vertical Yosemite style granite cleavage.
The analogy becomes more interesting when the landslide occurs with a 20+ story structure atop the hillside, I agree. I don't think any real-world situation has a slope near vertical enough to apply, unfortunately (fortunately?). No incidences of which I'm aware, probably due to lack of building permits in that context.
Personally, I like the lego-n-cardboard model much better. It's hard to get regularity and uniformity of structure, such that a homogenous model is generally acceptable, have crushing, and yet have intact upper structure. The issue of scaling has been discussed here in some detail and I believe that's the essential difficulty in reproduction of this phenomena. Once you get to the scale of commerical skyscrapers, maybe not so difficult, eh? But these human structures are far from equilibrium in a certain sense, well beyond what the earth's surface structure permits except in the most extreme circumstances (see Monument Valley). Thus, while I get the idea, it is my humble opinion that natural world examples (like landslide) have an inherent disadvantage and are of limited use.
Yes. Rain.
Many developments in southern California over at least the last 30 years have involved considerable reshaping of the earth prior to the first foundation going in. Whatever integrity existed, beyond that provided by previous vegetation, is also lost. In my comment, I'm distinguishing between the factors of:
- soil disruption - road cuts, grading, filling, leveling, etc
- vegetation changes, loss of root mass
- drainage changes
- addition of (and prior loss of) water and attendant effects - mass, lubrication, degaradation of integrity, induced pressure (including osmotic)
as opposed to the weight of the house bearing on earth below, either prior to or during the slide. Not saying the mass of structures above are insignificant, but compared to everything else associated with the presence of a house, maybe not so important. My opinion is the natural terrain of southern California can be classified into mountains, foothills, alluvials/bajada, washes, and dry (or soon to be) lakes. The erosion process is occasionally quite dramatic and discrete (see the Blackhawk slide) but largely gradual. The human earthworks merely accelerate and/or exacerbate the process locally by disrupting the long-term dynamic equilibrium of the landscape, as hundred or thousand year rains do but with different effect.
I see the house in this analogy as the functional equivalent of the antenna mast on the north tower - just along for the ride - where the upper portion of the hillside plays the role of the upper block. In casual observation I've seen plenty of examples of hillsides that have moved as an integral unit, but many more that moved as a non-integral flow, i.e., no 'structure' to crush. While I'd expect landslides and avalanches to be governed by the same basic mechanics, landslides span a spectrum from rock cleavage with minimal mass entrainment to mudslides with mimimal to significant entrainment. Everything from tumbling large blocks to pure fluid flow, as well, which may have some useful correspondence. You'd be hard pressed to find any sort of landslide, however, where the upper portion remains at all intact, other than perhaps some near-vertical Yosemite style granite cleavage.
The analogy becomes more interesting when the landslide occurs with a 20+ story structure atop the hillside, I agree. I don't think any real-world situation has a slope near vertical enough to apply, unfortunately (fortunately?). No incidences of which I'm aware, probably due to lack of building permits in that context.
Personally, I like the lego-n-cardboard model much better. It's hard to get regularity and uniformity of structure, such that a homogenous model is generally acceptable, have crushing, and yet have intact upper structure. The issue of scaling has been discussed here in some detail and I believe that's the essential difficulty in reproduction of this phenomena. Once you get to the scale of commerical skyscrapers, maybe not so difficult, eh? But these human structures are far from equilibrium in a certain sense, well beyond what the earth's surface structure permits except in the most extreme circumstances (see Monument Valley). Thus, while I get the idea, it is my humble opinion that natural world examples (like landslide) have an inherent disadvantage and are of limited use.
OneWhiteEye --- Vertical avalanche seems to have intuitive appeal for many. But not with regard to riding down on top, since you are the only person I am aware of who has actually done that.
QUOTE (David B. Benson+Apr 6 2008, 09:06 PM)
OneWhiteEye --- Vertical avalanche seems to have intuitive appeal for many. But not with regard to riding down on top, since you are the only person I am aware of who has actually done that.
I was the initiator and, thankfully, there was no crush-up at the end. The upper block of snow of that quasi-static avalanche was unchanged, uncompressed... like me, experiencing essentially the same upward force as sitting still. Had it accelerated, it would have been less force. The avalanche is a better analogy for me, too.
If we consider these time ranges for a tower:
1) Prior to impact
2) Post impact but prior to visible deformation
3) Deformation and tilt
4) Initial rapid descent, prior to significant crush layer accumulation or resistance
5) Crush down with layer and resistance, including terminal velocity if applicable
6) Crush up
7) Tumbling to pile at rest
By #5, the landlside analogy takes on increased viability. It's important to remember there are three spatial regions once a significant layer has accumulated in a crushing model; approximate homogeneity only applies to the undamaged upper and lower portions. Aside from any shock-absorbtion capability the layer provides, which tends to transmit impulse from discrete impacts on the bottom with some attenuation and over longer periods, the layer eventually acquires sufficient energy to sustain collapse on its own without aid of an upper block. The upper block is then riding down on the rubble much as a house does on a landslide. The upper block will experience less resisting force than it does in the static case, until terminal velocity is reached.
I was the initiator and, thankfully, there was no crush-up at the end. The upper block of snow of that quasi-static avalanche was unchanged, uncompressed... like me, experiencing essentially the same upward force as sitting still. Had it accelerated, it would have been less force. The avalanche is a better analogy for me, too.
If we consider these time ranges for a tower:
1) Prior to impact
2) Post impact but prior to visible deformation
3) Deformation and tilt
4) Initial rapid descent, prior to significant crush layer accumulation or resistance
5) Crush down with layer and resistance, including terminal velocity if applicable
6) Crush up
7) Tumbling to pile at rest
By #5, the landlside analogy takes on increased viability. It's important to remember there are three spatial regions once a significant layer has accumulated in a crushing model; approximate homogeneity only applies to the undamaged upper and lower portions. Aside from any shock-absorbtion capability the layer provides, which tends to transmit impulse from discrete impacts on the bottom with some attenuation and over longer periods, the layer eventually acquires sufficient energy to sustain collapse on its own without aid of an upper block. The upper block is then riding down on the rubble much as a house does on a landslide. The upper block will experience less resisting force than it does in the static case, until terminal velocity is reached.
I suspect solving the crush-down/crush-up equations as a coupled pair of diiferential equations with the same initial conditions would reveal an early crush phase of an upper block that diminishes until the resistive force increases sharply due to end of loose compaction phase.
QUOTE (OneWhiteEye+Apr 6 2008, 03:27 PM)
I suspect solving the crush-down/crush-up equations as a coupled pair of diiferential[sic] equations with the same initial conditions would reveal an early crush phase of an upper block that diminishes until the resistive force increases sharply due to end of loose compaction phase.
Yes. That is in the Bazant & Le discussion paper I mentioned previously. The collapse becomes pure crush-down within a fraction of a second, under the assumption of homogeneity.
Yes. That is in the Bazant & Le discussion paper I mentioned previously. The collapse becomes pure crush-down within a fraction of a second, under the assumption of homogeneity.
QUOTE (David B. Benson+Apr 6 2008, 11:52 PM)
Yes. That is in the Bazant & Le discussion paper I mentioned previously. The collapse becomes pure crush-down within a fraction of a second, under the assumption of homogeneity.
Thank you, guess I'd better catch up on my reading (and maybe spell check, too). Good thing my speculation was in agreement with published results!
I'll speculate further: in a discrete story model, the collapse would take longer to become pure crush-down.
Thank you, guess I'd better catch up on my reading (and maybe spell check, too). Good thing my speculation was in agreement with published results!
I'll speculate further: in a discrete story model, the collapse would take longer to become pure crush-down.
To explain a crush-down one of the requirements is also that the resistive force increases to the bottom (or the crushing energy increases). This is consistent with the fact that in the static situation the amount of static force a story delivers is proportional with the remaining height above it (assuming the floor slabs have equal mass). But this also implies that the force decreases when you go to the top. This makes the situation a little bit different.
einsteen
Basically, the floors were all the same, only the strength of the columns and frames got greater as you went down.
Grumpy
Basically, the floors were all the same, only the strength of the columns and frames got greater as you went down.
Grumpy
That's what I mean, and that implies they were weaker above the collapse zone
QUOTE (einsteen+Apr 7 2008, 08:01 AM)
To explain a crush-down one of the requirements is also that the resistive force increases to the bottom (or the crushing energy increases). This is consistent with the fact that in the static situation the amount of static force a story delivers is proportional with the remaining height above it (assuming the floor slabs have equal mass). But this also implies that the force decreases when you go to the top. This makes the situation a little bit different.
The point to recognize is that if the crush down was taking out the floor trusses and thus the lateral stability of the columns, then the compressive strength of the columns does not enter into it. The ability of any floor span to resist the mass falling on it was the same all the way down since every floor was more or less equal in that regard.
The point to recognize is that if the crush down was taking out the floor trusses and thus the lateral stability of the columns, then the compressive strength of the columns does not enter into it. The ability of any floor span to resist the mass falling on it was the same all the way down since every floor was more or less equal in that regard.
For a pure pancaking phenomenon that is true, then all floors could easily be detached from the building, in that case the whole collapse is determined by momentum transfer. But that also means that core and perimeter columns will stand after the front passes by and then lose their stability and fall.
But that is not what we observe during the first seconds, we observe a whole 15 story top section including hat truss and antenna and everything within falling with an acceleration (2/3)g. This does not include the possible hinge effect in the beginning, which is an open problem to be solved. Since the total of the columns crush also with (2/3)g it is therefore nice to use the total crush energy in a model, strictly that model will only work if the force decreases to the bottom. But that difference can mathematically be made as small as you want I would say.
But that is not what we observe during the first seconds, we observe a whole 15 story top section including hat truss and antenna and everything within falling with an acceleration (2/3)g. This does not include the possible hinge effect in the beginning, which is an open problem to be solved. Since the total of the columns crush also with (2/3)g it is therefore nice to use the total crush energy in a model, strictly that model will only work if the force decreases to the bottom. But that difference can mathematically be made as small as you want I would say.
In fact the first few floors of travel the crush down may have been primarily a pancaking. However we also see the perimeter columns peeling away indicating that they are being forced outward by the bulk of falling debris and not connected to the trusses.
The non-connection to the trusses is consistent with a pancaking. So what of the core columns. The floors have also been torn away from them so there is no lateral support other than the beams connecting the core columns to each other, no, or very little, diagonal bracing. The beams would also likely be torn away shortly after the wide spans. The core column sections are 30 feet long and connected in staggered heights. The connections would represent a stiff part of a long column then, that is being bent. It will snap at that point. Now the falling debris contains 30 foot sections of interior column that will impact adjacent columns.
Although the energy required to snap lower sections of the core columns would have to be greater we also know that the mass of falling debris is greater as is the velocity of that debris and thus the percentage of available energy (at any one point in time) used to do this would be small all the way down.
The idea that in a pancaking collapse that the core should have stood alone until it succumbed to the inherent instability of such a long (relatively) thin column ignores the extreme buffeting that the core would be undergoing from impacts of debris, and the fact that when the upper portion started to fall that its core columns were impacting the core floor areas(inter-column bracing). At best the core columns would have had to stand individually alone, not as an intact core. The so-called 'spire' shows this to be true. It contained few intercolumn beams and the long individual columns very quickly succumbed to their instability. A similar thing may have been occuring all the way down, hidden by the dust cloud, and only became visible at the point where the collapse progression zone and dust cloud hit ground level.
The suggestion that the perimeter column trees would also remain also ignores the buffeting they would be receiving from the debris falling within the tower. We see that the lighter debris is being thrown outward very fast as soon as the collapse begins. The lightest of this debris is likely being propelled by the outrush of compressed air but the falling debris is also hitting the floors and tearing them loose. The average acelleration is 2/3 g which allows up to 1/3g to contribute to the force to acellerate debris outward. Whatever energy does not go into propigating the collapse, or into heat or sound, has to go somewhere right.
The non-connection to the trusses is consistent with a pancaking. So what of the core columns. The floors have also been torn away from them so there is no lateral support other than the beams connecting the core columns to each other, no, or very little, diagonal bracing. The beams would also likely be torn away shortly after the wide spans. The core column sections are 30 feet long and connected in staggered heights. The connections would represent a stiff part of a long column then, that is being bent. It will snap at that point. Now the falling debris contains 30 foot sections of interior column that will impact adjacent columns.
Although the energy required to snap lower sections of the core columns would have to be greater we also know that the mass of falling debris is greater as is the velocity of that debris and thus the percentage of available energy (at any one point in time) used to do this would be small all the way down.
The idea that in a pancaking collapse that the core should have stood alone until it succumbed to the inherent instability of such a long (relatively) thin column ignores the extreme buffeting that the core would be undergoing from impacts of debris, and the fact that when the upper portion started to fall that its core columns were impacting the core floor areas(inter-column bracing). At best the core columns would have had to stand individually alone, not as an intact core. The so-called 'spire' shows this to be true. It contained few intercolumn beams and the long individual columns very quickly succumbed to their instability. A similar thing may have been occuring all the way down, hidden by the dust cloud, and only became visible at the point where the collapse progression zone and dust cloud hit ground level.
The suggestion that the perimeter column trees would also remain also ignores the buffeting they would be receiving from the debris falling within the tower. We see that the lighter debris is being thrown outward very fast as soon as the collapse begins. The lightest of this debris is likely being propelled by the outrush of compressed air but the falling debris is also hitting the floors and tearing them loose. The average acelleration is 2/3 g which allows up to 1/3g to contribute to the force to acellerate debris outward. Whatever energy does not go into propigating the collapse, or into heat or sound, has to go somewhere right.
I'm not sure if everything can be explained by compressed air that leaves the building. In wtc7 there were also some of these effects on top (although very small) while that was a crush-up and by definition in a crush-up the air only leaves the story that compacts. In some of the wtc videos you also see that some relatively large objects are ejected, one of them even with 13 m/s in the very first beginning of the collapse, I don't believe that air can explain that, even with released strain energy it is hard to explain. But Yes, the collapse is of course a complex event, the nice thing is that when you know the acceleration in the beginning or the collapse time for some period then it would be possible to estimate that energy that is lost, assuming pancaking for example, if that loss is about 0.5 GJ per story then it is very interesting to wonder what kind of process it is, in that case it is more complex than floors simply breaking at the bolts etc, but if you know that value you could call it effective collapse energy for example.
do you guys deny that there could have been some other factors in the collapse besides the building just falling (building 7 for example). It could have fell the way lots of you say (just the fires), but could there also be another hidden factor?
I think that if the buildings did fall to the plane impacts and fires alone, then Bush at least knew of the attacks ahead of time and saw it as a way to enter the war.
I think that if the buildings did fall to the plane impacts and fires alone, then Bush at least knew of the attacks ahead of time and saw it as a way to enter the war.
Fusilli_Jerry89 ---- This is a sci-tech site. No politics. If you must post regarding political affairs, please take it elsewhere.
QUOTE (Fusilli_Jerry89+Apr 8 2008, 08:39 PM)
do you guys deny that there could have been some other factors in the collapse besides the building just falling (building 7 for example). It could have fell the way lots of you say (just the fires), but could there also be another hidden factor
That simply introduces factors not in evidence. When it can be shown that it is entirely within the realm of probability that the impact damages and the fire damage caused the collapses, as seen in the videos, AND there is no evidence of any other factors then speculating on other factors is simply that, speculation.
QUOTE
I think that if the buildings did fall to the plane impacts and fires alone, then Bush at least knew of the attacks ahead of time and saw it as a way to enter the war.
As noted above, this sentiment is in no way is a sci-tech topic and belongs in a political discussion.
This is the newest attempt to determine tilt(time) for the south tower
frame,alpha
0, 0.0
10, 0.7
20, 0.0
25, 0.0
27, 0.2
28, 0.3
29, 0.3
30, 0.0
31, 0.2
32, 0.3
33, 0.6
35, 0.6
40, 0.3
50, 1.2
60, 1.5
70, 2.2
80, 3.1
90, 5.2
100, 7.5
110, 10.6
120, 13.5
130, 13.6
140, 16.6
180, 18.4
185, 22.4
205, 26.7
The video had 30 frames per second. Extracted them, picked a couple out of it and manually fitted a line on the frames and determined the angle.
This is the plot
South Tower's tilt as function of frame
It is hard to measure the tilt later because there appears a kink as follows
---\___
And don't forgot the smoke and dust. Some points are messed up, but it still looks like the function switches from convex to concave. One should also determine the position of the block but for that an other movie is needed because the one used doesn't show the roof in the beginning.
ps. movie here:
911.wtc.2.demolition.north.very.close.mpg
frame,alpha
0, 0.0
10, 0.7
20, 0.0
25, 0.0
27, 0.2
28, 0.3
29, 0.3
30, 0.0
31, 0.2
32, 0.3
33, 0.6
35, 0.6
40, 0.3
50, 1.2
60, 1.5
70, 2.2
80, 3.1
90, 5.2
100, 7.5
110, 10.6
120, 13.5
130, 13.6
140, 16.6
180, 18.4
185, 22.4
205, 26.7
The video had 30 frames per second. Extracted them, picked a couple out of it and manually fitted a line on the frames and determined the angle.
This is the plot
South Tower's tilt as function of frame
It is hard to measure the tilt later because there appears a kink as follows
---\___
And don't forgot the smoke and dust. Some points are messed up, but it still looks like the function switches from convex to concave. One should also determine the position of the block but for that an other movie is needed because the one used doesn't show the roof in the beginning.
ps. movie here:
911.wtc.2.demolition.north.very.close.mpg
If you look at the plot you would say that frame 130 is incorrect, but the tower topples smoothly and after some time it goes almost straight down, after that it gets some resistance and again wants to topple away from the building, this is also consistent with the fact that the kink is in the upper part of the building, that can only be there if there is resistance. After that the tilting continues quickly and it becomes covered in dust.
note: the extracted frame numbers don't start at t=0 on the video.
note: the extracted frame numbers don't start at t=0 on the video.
Einsteen:
Nice video!
If you take the start of the steady tipping motion of WTC 2 to be at ~ frame 30 and you give data out to frame 205, that's 175 frames of tilting. At 30 frames per second that equals 5.8 seconds. I am a little surprised at this number. Are you sure about the frame rate? Also you can estimate the rate of drop which occurs at the same time as the tilt. Before it disappeared into the smoke and debris, the upper block was falling at about 20 m/s.
Nice video!
If you take the start of the steady tipping motion of WTC 2 to be at ~ frame 30 and you give data out to frame 205, that's 175 frames of tilting. At 30 frames per second that equals 5.8 seconds. I am a little surprised at this number. Are you sure about the frame rate? Also you can estimate the rate of drop which occurs at the same time as the tilt. Before it disappeared into the smoke and debris, the upper block was falling at about 20 m/s.
Neu, I think it is correct, I used good old virtualdub to verify it. But very good that you asked this, I checked it frame by frame and it seems that every
6th frame is a duplicate of the 5th frame, in other words there are 5 unique frames that change and then the next one is a copy of the last one
and so on and there are 30 frames in a second.
This implies that the framerate of the original video was 25 and it has been changed to 30, but be careful, it was a
frame rate conversion and no source rate adjustment. I've tested it with a 25fps TV capture, if I convert it to 30fps
then per second it needs more samples and duplicates one, but that means it is still realtime. For a source rate adjustment the video will run at 30fps and each frame will be unique, then the time is really scaled with a factor 6/5
6th frame is a duplicate of the 5th frame, in other words there are 5 unique frames that change and then the next one is a copy of the last one
and so on and there are 30 frames in a second.
This implies that the framerate of the original video was 25 and it has been changed to 30, but be careful, it was a
frame rate conversion and no source rate adjustment. I've tested it with a 25fps TV capture, if I convert it to 30fps
then per second it needs more samples and duplicates one, but that means it is still realtime. For a source rate adjustment the video will run at 30fps and each frame will be unique, then the time is really scaled with a factor 6/5
That's a hell of a video and the quality is good, not the usual compressed and re compressed ones that we see so much of.
Especially striking was the very short time that a 'hinge' exists. As soon as that 'hinge' fails the upper section would be rotating about its center of mass rather than about the hinge.
That is also when the center of mass begins moving straight down. What frame in the video corresponds to the time that the 'hinge' fails? (roughly)
Especially striking was the very short time that a 'hinge' exists. As soon as that 'hinge' fails the upper section would be rotating about its center of mass rather than about the hinge.
That is also when the center of mass begins moving straight down. What frame in the video corresponds to the time that the 'hinge' fails? (roughly)
NTSC frame rate is 29.97 fps (59.94 fields per second) native
Film is 24 fps and indeed frames do get repeated in a conversion (telecine) to video.
//forum.videohelp.com/topic316780.html
not allowed to BB links yet
Film is 24 fps and indeed frames do get repeated in a conversion (telecine) to video.
//forum.videohelp.com/topic316780.html
not allowed to BB links yet
aydeehess --- For WTC 1, the hinge fails around 0.8--1.0 second after collapse sensibly commences.
QUOTE (einsteen+Apr 1 2008, 06:56 AM)
That's great Shagster. This is indeed the classical domino effect but that was not what happened with the top section, the man should still lie in his bed and the core columns (not there) have to buckle in order to get his bed moved downwards as an intact whole.
The collapsing triple-decker bed was an April Fool's video.
The collapsing triple-decker bed was an April Fool's video.
Shagster, you got me with that one!
Neu-Fonze, I was reading at the jref, but I stopped there and I am a man of words and will never post a single dot there. You said something about the 2 degrees leaning that was already there. I disagree very much.
Picture showing no Leaning before collapse
In determining tilt(time) I used the line below as a reference, from this image you see that it is a straight line, of course the camera could rotate a little bit, even if it is one pixel difference I would like to know how you determined the 2 degrees.
And what happens afterwards is in my humble opinion totally consistent with 47 core columns that fail at about the same time, the perimeter columns cannot hold the top section and we will have buckling of perimeter columns, they will snap, it is the end of the story.
Neu-Fonze, I was reading at the jref, but I stopped there and I am a man of words and will never post a single dot there. You said something about the 2 degrees leaning that was already there. I disagree very much.
Picture showing no Leaning before collapse
In determining tilt(time) I used the line below as a reference, from this image you see that it is a straight line, of course the camera could rotate a little bit, even if it is one pixel difference I would like to know how you determined the 2 degrees.
And what happens afterwards is in my humble opinion totally consistent with 47 core columns that fail at about the same time, the perimeter columns cannot hold the top section and we will have buckling of perimeter columns, they will snap, it is the end of the story.
Einsteen:
Well I know how you feel about some of the posters over at JREF, but glad to see you can still post here.... after all YOU were the one who said this thread will never die!
Now all you have to do is keep posting here to prove your point; but that's what's called a self-fulfilling prophecy!
Anyway....
I conclude that the upper section of WTC 2 was tilted by about 2 degrees BEFORE the collapse started by looking at the video you posted in steps of about 1/4 sec. I would claim that there is no significant downward motion for the first 1-2 seconds of that clip. I have estimated the moment the real fast tipping starts to coincide with the upper section being about 0.5 cm from vertical as measured at the top of the image on my TV screen.....
but yes, in the end, I have to admit:
I EYEBALL IT!
(Sorry, this poor guy has no fancy image processing softwear. Right now I can hardly afford new underwear!)
So, my estimable friend Einsteen, that's what I think ..... and it agrees with what I concluded about a year ago looking at another WTC 2 collapse video.
Well I know how you feel about some of the posters over at JREF, but glad to see you can still post here.... after all YOU were the one who said this thread will never die!
Now all you have to do is keep posting here to prove your point; but that's what's called a self-fulfilling prophecy!
Anyway....
I conclude that the upper section of WTC 2 was tilted by about 2 degrees BEFORE the collapse started by looking at the video you posted in steps of about 1/4 sec. I would claim that there is no significant downward motion for the first 1-2 seconds of that clip. I have estimated the moment the real fast tipping starts to coincide with the upper section being about 0.5 cm from vertical as measured at the top of the image on my TV screen.....
but yes, in the end, I have to admit:
I EYEBALL IT!
(Sorry, this poor guy has no fancy image processing softwear. Right now I can hardly afford new underwear!)
So, my estimable friend Einsteen, that's what I think ..... and it agrees with what I concluded about a year ago looking at another WTC 2 collapse video.
I post at JREF and do note that the moderating here seems tighter.
Can someone condense what the video shows as far as determining the mechanism of collapse?
Perimeter columns were damaged along one side, core columns lost strength and the portion of the building above tilted in the direction of that damage. The perimeter columns on the side away from the tilt certainly could remain in tension in the fashion.
Core columns are either in compression or tension, all are being bent.
Once columns begin failing they quickly transfer load to other columns which then also fail and once a critical point is reached the upper section crushs down while still rotating slowly about its center of mass but the CoM is following gravity's accelleration vector, straight down.
Can someone condense what the video shows as far as determining the mechanism of collapse?
Perimeter columns were damaged along one side, core columns lost strength and the portion of the building above tilted in the direction of that damage. The perimeter columns on the side away from the tilt certainly could remain in tension in the fashion.
Core columns are either in compression or tension, all are being bent.
Once columns begin failing they quickly transfer load to other columns which then also fail and once a critical point is reached the upper section crushs down while still rotating slowly about its center of mass but the CoM is following gravity's accelleration vector, straight down.
Dr. Paul LaViolette has added to his web re experimental verification of his theory of subquantum kinetics. I don't think his theory is mathematical enough to impress most physicists, but OTOH he seems to have found too many verifications of his theory for him to be completely wrong. Unfortunately, it is almost impossible for me to find a Ph.D. physicist's writing on his work.
In any event, for whatever it's worth, from http://www.etheric.com/LaViolette/Predict2.html
Verification (2008): The prediction with respect to the force exerted by the gravity potential component of such waves was verified qualitatively. Paul LaViolette contacted Dr. Eugene Podkletnov and inquired about the performance of his gravity impulse beam generator. Previously Drs. Podkletnov and Modanese had reported in a published paper that the impulse beam was able to deflect a test mass up to 14 centimeters when 2 million volts were discharged through the generator's superconducting cathode disc (Podkletnov and Modanese, 2002). Podkletnov had subsequently told LaViolette that the beam was able to punch 4 inch holes through concrete blocks when 10 million volt pulses were discharged through the disk. In January 2008, LaViolette asked Podkletnov if his team used a different electric pulse generator to produce the gravity pulses that punched holes through concrete blocks as compared with the ones that produced the 14 centimeter pendulum deflections and whether the former used a different Marx capacitor bank that was able to create a pulse with a steeper gradient. Dr. Podkletnov concurred that was indeed the case, the concrete smashing pulses were created with an electric discharge that had a much more rapid voltage rise-time.
Verification (2008): The prediction with respect to the superluminal speed of gravity potential component of such waves was verified qualitatively. Previously, Dr. Podkletnov had told LaViolette that he and Dr. Modanese had measured the speed of the pulses to be between 63 and 64 times the speed of light. In January of 2008, LaViolette asked Podkletnov whether the concrete smashing pulses produced by the steeper electric field gradients traveled much faster than the pendulum deflecting pulses. Podkletnov concurred and said that they had determined that these stronger pulses traveled at least several thousand times the speed of light.
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
Unfortunately, I don't know how we could possibly verify any such claims....
I've read through the Podkletnov paper that LaViolette links to, and the pendulum deflecting beam has no (measurable) distance dependence, yet exerts a force proportional to the mass of the pendulum. So, it's gravitation like in one way, and anything but in another.
I've not read anything more about the faster "concrete smashing" pulses than what is in the quotes above.
In any event, for whatever it's worth, from http://www.etheric.com/LaViolette/Predict2.html
QUOTE
Verification (2008): The prediction with respect to the force exerted by the gravity potential component of such waves was verified qualitatively. Paul LaViolette contacted Dr. Eugene Podkletnov and inquired about the performance of his gravity impulse beam generator. Previously Drs. Podkletnov and Modanese had reported in a published paper that the impulse beam was able to deflect a test mass up to 14 centimeters when 2 million volts were discharged through the generator's superconducting cathode disc (Podkletnov and Modanese, 2002). Podkletnov had subsequently told LaViolette that the beam was able to punch 4 inch holes through concrete blocks when 10 million volt pulses were discharged through the disk. In January 2008, LaViolette asked Podkletnov if his team used a different electric pulse generator to produce the gravity pulses that punched holes through concrete blocks as compared with the ones that produced the 14 centimeter pendulum deflections and whether the former used a different Marx capacitor bank that was able to create a pulse with a steeper gradient. Dr. Podkletnov concurred that was indeed the case, the concrete smashing pulses were created with an electric discharge that had a much more rapid voltage rise-time.
Verification (2008): The prediction with respect to the superluminal speed of gravity potential component of such waves was verified qualitatively. Previously, Dr. Podkletnov had told LaViolette that he and Dr. Modanese had measured the speed of the pulses to be between 63 and 64 times the speed of light. In January of 2008, LaViolette asked Podkletnov whether the concrete smashing pulses produced by the steeper electric field gradients traveled much faster than the pendulum deflecting pulses. Podkletnov concurred and said that they had determined that these stronger pulses traveled at least several thousand times the speed of light.
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
Unfortunately, I don't know how we could possibly verify any such claims....
I've read through the Podkletnov paper that LaViolette links to, and the pendulum deflecting beam has no (measurable) distance dependence, yet exerts a force proportional to the mass of the pendulum. So, it's gravitation like in one way, and anything but in another.
I've not read anything more about the faster "concrete smashing" pulses than what is in the quotes above.
Yes Neu, it looks indeed like that. There are so much tools out, in this case even good old mspaint would do the job, but for a good tilt(time) function OneWhiteEye's trickbox is needed, maybe even an effective resolution less than a pixel could be measured. The jref thread seems to be interesting and entertaining...
QUOTE (metamars+Apr 20 2008, 09:56 AM)
I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
QUOTE (metamars+Apr 20 2008, 04:56 PM)
Dr. Paul LaViolette has added to his web re experimental verification of his theory of subquantum kinetics. I don't think his theory is mathematical enough to impress most physicists, but OTOH he seems to have found too many verifications of his theory for him to be completely wrong. Unfortunately, it is almost impossible for me to find a Ph.D. physicist's writing on his work.
In any event, for whatever it's worth, from http://www.etheric.com/LaViolette/Predict2.html
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
Unfortunately, I don't know how we could possibly verify any such claims....
I've read through the Podkletnov paper that LaViolette links to, and the pendulum deflecting beam has no (measurable) distance dependence, yet exerts a force proportional to the mass of the pendulum. So, it's gravitation like in one way, and anything but in another.
I've not read anything more about the faster "concrete smashing" pulses than what is in the quotes above.
I wrote the following to Podkletnov, via email:
I found the report by Dr. LaViolette that you and your team have managed to "smash concrete" ( http://www.etheric.com/LaViolette/Predict2.html ) to be fascinating. I was hoping to get more information, in particular about the granularity of the resulting smashed bits, whether one could distinguish concrete smashed in this manner from, say, concrete smashed via a sledgehammer, and also whether or not there are videos and research reports extant, or "in the pipeline" on this subject.
Finally, I would be curious as to your opinion as to why there is not more research along the lines of your work. Violations of the speed of light limit are Nobel-prize worthy endeavors. One would think that there'd be a stampede of physicists looking to verify your work, all over the world.
He replied:
He replied:
Thank you for your interest to the experimental gravity research. The effect of the gravity impulse on the concrete wall is not similar to the action of a sledge hammer as practically all the molecules of concrete undergo the action of an impulse simultaneously. The structure of the particles (petro graphical analysis) shows nothing peculiar and as compared to the action of a normal explosive and does not demonstrate any strains and stresses inside the material. If the wall is not very thick 4-5 inches without metal ribs inside, it is possible to cut a cement cylinder if the impulse is fast in time and really strong (small erection time of the voltage across the emitter). If the cement is not strong we just obtain small pieces mostly with the size of 0.3 -0.5 inch. We made no videos as our lab is in the restricted area, our tests are not secret ones but our neighbours are classified.
About violations of the laws, first of all we talk about the flow of gravity waves or a flow in the ether where the particles have the size several orders of magnitude smaller than the electron and, therefore, have no mass, so we do not break the law. Also Dr. Einstein was a great practical joker, he got his Nobel Prize for the works with photo effect. The theory of relativity is only a theory. And, by the way, even normal matter can move with the speeds exceeding the speed of light but in that case the motion in the ether will cause the emission of synchrotron radiation. The speed of light is a constant like the speed of sound, earlier it was considered impossible for the planes to fly faster than the sound, now 3-5 mah(sic) is normal. The field of gravity is not studied at all, it is a white spot. Nobody wants to loose his reputation and his job, the example of prof. Eric Laithwait is one more proof. Still my interest is not a gravity gun but a new propulsion system using artificial gravity. If you meet a wise man who is willing to invest 80 mln Euros for 6-7 years, please let me know. I am dead serious and will devote all my knowledge and energy working with a team of scientists and engineers creating this wonder.
I wish you all the best Eugene Podkletnov
I have to admit, my physics profs of days gone by would raise an eyebrow at
"And, by the way, even normal matter can move with the speeds exceeding the speed of light but in that case the motion in the ether will cause the emission of synchrotron radiation. " However, they never shot up concrete with a gravity gun!
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
In any event, for whatever it's worth, from http://www.etheric.com/LaViolette/Predict2.html
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
Unfortunately, I don't know how we could possibly verify any such claims....
I've read through the Podkletnov paper that LaViolette links to, and the pendulum deflecting beam has no (measurable) distance dependence, yet exerts a force proportional to the mass of the pendulum. So, it's gravitation like in one way, and anything but in another.
I've not read anything more about the faster "concrete smashing" pulses than what is in the quotes above.
I wrote the following to Podkletnov, via email:
QUOTE
I found the report by Dr. LaViolette that you and your team have managed to "smash concrete" ( http://www.etheric.com/LaViolette/Predict2.html ) to be fascinating. I was hoping to get more information, in particular about the granularity of the resulting smashed bits, whether one could distinguish concrete smashed in this manner from, say, concrete smashed via a sledgehammer, and also whether or not there are videos and research reports extant, or "in the pipeline" on this subject.
Finally, I would be curious as to your opinion as to why there is not more research along the lines of your work. Violations of the speed of light limit are Nobel-prize worthy endeavors. One would think that there'd be a stampede of physicists looking to verify your work, all over the world.
He replied:
QUOTE (->
| QUOTE |
I found the report by Dr. LaViolette that you and your team have managed to "smash concrete" ( http://www.etheric.com/LaViolette/Predict2.html ) to be fascinating. I was hoping to get more information, in particular about the granularity of the resulting smashed bits, whether one could distinguish concrete smashed in this manner from, say, concrete smashed via a sledgehammer, and also whether or not there are videos and research reports extant, or "in the pipeline" on this subject. Finally, I would be curious as to your opinion as to why there is not more research along the lines of your work. Violations of the speed of light limit are Nobel-prize worthy endeavors. One would think that there'd be a stampede of physicists looking to verify your work, all over the world. |
He replied:
Thank you for your interest to the experimental gravity research. The effect of the gravity impulse on the concrete wall is not similar to the action of a sledge hammer as practically all the molecules of concrete undergo the action of an impulse simultaneously. The structure of the particles (petro graphical analysis) shows nothing peculiar and as compared to the action of a normal explosive and does not demonstrate any strains and stresses inside the material. If the wall is not very thick 4-5 inches without metal ribs inside, it is possible to cut a cement cylinder if the impulse is fast in time and really strong (small erection time of the voltage across the emitter). If the cement is not strong we just obtain small pieces mostly with the size of 0.3 -0.5 inch. We made no videos as our lab is in the restricted area, our tests are not secret ones but our neighbours are classified.
About violations of the laws, first of all we talk about the flow of gravity waves or a flow in the ether where the particles have the size several orders of magnitude smaller than the electron and, therefore, have no mass, so we do not break the law. Also Dr. Einstein was a great practical joker, he got his Nobel Prize for the works with photo effect. The theory of relativity is only a theory. And, by the way, even normal matter can move with the speeds exceeding the speed of light but in that case the motion in the ether will cause the emission of synchrotron radiation. The speed of light is a constant like the speed of sound, earlier it was considered impossible for the planes to fly faster than the sound, now 3-5 mah(sic) is normal. The field of gravity is not studied at all, it is a white spot. Nobody wants to loose his reputation and his job, the example of prof. Eric Laithwait is one more proof. Still my interest is not a gravity gun but a new propulsion system using artificial gravity. If you meet a wise man who is willing to invest 80 mln Euros for 6-7 years, please let me know. I am dead serious and will devote all my knowledge and energy working with a team of scientists and engineers creating this wonder.
I wish you all the best Eugene Podkletnov
I have to admit, my physics profs of days gone by would raise an eyebrow at
"And, by the way, even normal matter can move with the speeds exceeding the speed of light but in that case the motion in the ether will cause the emission of synchrotron radiation. " However, they never shot up concrete with a gravity gun!
QUOTE (metamars+Apr 23 2008, 05:34 AM)
"And, by the way, even normal matter can move with the speeds exceeding the speed of light but in that case the motion in the ether will cause the emission of synchrotron radiation. "
Yes, the speed of light in water, for example. See Čerenkov radiation
Yes, the speed of light in water, for example. See Čerenkov radiation
QUOTE (metamars+Apr 23 2008, 12:34 PM)
I wrote the following to Podkletnov, via email:
I sent another email to Podkletnov, in which I asked about changing the beam's direction similarly to an electron gun in a TV monitor, and also curving it (which I considered very unlikely to be doable). His answer:
Thank you for your support, I really appreciate it. About your questions, it is impossible to curve the beam but if we speak about modification of the local gravity field, you can have a look at my earlier work with rotating SC disk:
http://xxx.lanl.gov/abs/cond-mat/9701074
At present we have the knowledge that allows to reduce the weight of objects up to 30-32% of their weight. In fact you are absolutely right, this technology allows to produce energy in a very efficient and cheap way.
Regards Eugene
Not having studied this paper, I'm not sure what it'll tell me about this issue.
I sent another email to Podkletnov, in which I asked about changing the beam's direction similarly to an electron gun in a TV monitor, and also curving it (which I considered very unlikely to be doable). His answer:
QUOTE
Thank you for your support, I really appreciate it. About your questions, it is impossible to curve the beam but if we speak about modification of the local gravity field, you can have a look at my earlier work with rotating SC disk:
http://xxx.lanl.gov/abs/cond-mat/9701074
At present we have the knowledge that allows to reduce the weight of objects up to 30-32% of their weight. In fact you are absolutely right, this technology allows to produce energy in a very efficient and cheap way.
Regards Eugene
Not having studied this paper, I'm not sure what it'll tell me about this issue.
ahhh metamars, if you are going to post this around the internet then let me reciprocate.
Let me explain why this is a hoax flag for me.
He claims that his experiments are not classified or secret.
Given the enormity of the discovery, if true, and the many applications to which this could be put it is unfathomable how this would not be a well kept secret by his government at least until it is perfected and more fully understood. As a weapon it would be valuable in that there is no way to shield against it, in fact traditional shielding would be counter-productive if the effect is proportional to the mass of the target.
Then there is the claim that he cannot video his experiment due to there being other, classified, work being done in the same lab. There are many ways to mask off nearby equipment from a video camera. Simply tarping over them while the video camera is present will suffice. Posting security in the room would make sure that no one lifts the tarp. They trust him enough to be in the same lab, in close proximity to the classified work so he is not the problem.
Even IF they decided that it just would not do to have a camera in the same building then just dismantle the experiment and move it to a location where camera work is not a problem.
Then there is the funding. Once again it can be pointed out that whoever patented this would be rich, rich, rich. A government that owned the tech would be able to undercut NASA or the European Space Agency in orbital launch costs as all the energy required would no longer have to be stored in rocket fuel on the spacecraft. 80 million Euros, peanuts to any moderately large country wishing to be a world power.
But, no, instead they are lowered to having to beg bucks from many people. They will not be getting 80 million Euros from one investor so they will have to work with a large number of smaller investors. This will mean that money is slower to come in and thus their research will advance at a slower pace. If they got 20 million per year for 4 years they could have a breakthrough and start making that money back for investors at 5 years. However if they can only raise 1 million per year it will take 20-25 years before those small investors would see a return on investment. The long sighted investor then might want to do this given the financial windfall in 25 years.
BUT, if this is a scam then the perpetrators are getting $1million/year and appeasing investors by telling them not to expect a return on investment for 25 years. A scam in which it will be at least a decade before many people start questioning whether or not they've been had,,,,lovely!
All that said, I would love to believe that someone has decoded the mystery of gravity and found a way to manipulate it. It would absolutely change the world, indeed the universe, we live in. Many of our sci-fi fantasies would be possible such as ftl travel.
However the old adage stands, if it sounds too good to be true, it probably isn't true. It still might be true but it bears close scrutiny and so far these guys just don't pass muster.
Let me explain why this is a hoax flag for me.
He claims that his experiments are not classified or secret.
Given the enormity of the discovery, if true, and the many applications to which this could be put it is unfathomable how this would not be a well kept secret by his government at least until it is perfected and more fully understood. As a weapon it would be valuable in that there is no way to shield against it, in fact traditional shielding would be counter-productive if the effect is proportional to the mass of the target.
Then there is the claim that he cannot video his experiment due to there being other, classified, work being done in the same lab. There are many ways to mask off nearby equipment from a video camera. Simply tarping over them while the video camera is present will suffice. Posting security in the room would make sure that no one lifts the tarp. They trust him enough to be in the same lab, in close proximity to the classified work so he is not the problem.
Even IF they decided that it just would not do to have a camera in the same building then just dismantle the experiment and move it to a location where camera work is not a problem.
Then there is the funding. Once again it can be pointed out that whoever patented this would be rich, rich, rich. A government that owned the tech would be able to undercut NASA or the European Space Agency in orbital launch costs as all the energy required would no longer have to be stored in rocket fuel on the spacecraft. 80 million Euros, peanuts to any moderately large country wishing to be a world power.
But, no, instead they are lowered to having to beg bucks from many people. They will not be getting 80 million Euros from one investor so they will have to work with a large number of smaller investors. This will mean that money is slower to come in and thus their research will advance at a slower pace. If they got 20 million per year for 4 years they could have a breakthrough and start making that money back for investors at 5 years. However if they can only raise 1 million per year it will take 20-25 years before those small investors would see a return on investment. The long sighted investor then might want to do this given the financial windfall in 25 years.
BUT, if this is a scam then the perpetrators are getting $1million/year and appeasing investors by telling them not to expect a return on investment for 25 years. A scam in which it will be at least a decade before many people start questioning whether or not they've been had,,,,lovely!
All that said, I would love to believe that someone has decoded the mystery of gravity and found a way to manipulate it. It would absolutely change the world, indeed the universe, we live in. Many of our sci-fi fantasies would be possible such as ftl travel.
However the old adage stands, if it sounds too good to be true, it probably isn't true. It still might be true but it bears close scrutiny and so far these guys just don't pass muster.
jaydeehess --- As I posted earlier,
QUOTE (jaydeehess+Apr 24 2008, 02:24 AM)
All that said, I would love to believe that someone has decoded the mystery of gravity and found a way to manipulate it.
Even if you can harness a hitherto unharnessed, gravity-like force, it in no way means that you understand how it works. While I could be mistaken on this point, I think that for most major discoveries, experiment leads theory, anyways.
Furthermore, if you had bothered to read one of the papers I linked to, you would have seen the claim that others, including NASA, have attempted to create the same effect. You can posture all you want on the internet, but if you make no serious attempt at research, why should I care what you think? I'm not saying you don't raise any good points at all (some were silly, also, but I don't want to spend the time pointing them out), but nothing you've written, here or at JREF, comes close to nailing this down. If you were a journalist, being paid good money to track down this story, is this how you'd proceed to determine whether it's true or whether it's a hoax?
If it's true that NASA tried to reproduce the PM work, isn't it a logical first step to contact them, and get their evaluation? Then, too, government agencies sometimes lie. So, a real journalist wouldn't stop with 1 negative report. Instead, he/she would would make numerous inquiries, of different parties, to find out who else may have attempted to reproduce this, and what their results were.
If I thought you were sincere, I'd give you yet another pointer as to how you could check this out, but I'm not going to bother. Since it's suggested by common sense, as a debunker gifted with stellar logic, you should be able to figure it out on your own, anyway.
Even if you can harness a hitherto unharnessed, gravity-like force, it in no way means that you understand how it works. While I could be mistaken on this point, I think that for most major discoveries, experiment leads theory, anyways.
Furthermore, if you had bothered to read one of the papers I linked to, you would have seen the claim that others, including NASA, have attempted to create the same effect. You can posture all you want on the internet, but if you make no serious attempt at research, why should I care what you think? I'm not saying you don't raise any good points at all (some were silly, also, but I don't want to spend the time pointing them out), but nothing you've written, here or at JREF, comes close to nailing this down. If you were a journalist, being paid good money to track down this story, is this how you'd proceed to determine whether it's true or whether it's a hoax?
If it's true that NASA tried to reproduce the PM work, isn't it a logical first step to contact them, and get their evaluation? Then, too, government agencies sometimes lie. So, a real journalist wouldn't stop with 1 negative report. Instead, he/she would would make numerous inquiries, of different parties, to find out who else may have attempted to reproduce this, and what their results were.
If I thought you were sincere, I'd give you yet another pointer as to how you could check this out, but I'm not going to bother. Since it's suggested by common sense, as a debunker gifted with stellar logic, you should be able to figure it out on your own, anyway.
QUOTE (metamars+Apr 25 2008, 12:48 AM)
Even if you can harness a hitherto unharnessed, gravity-like force, it in no way means that you understand how it works. While I could be mistaken on this point, I think that for most major discoveries, experiment leads theory, anyways.
Furthermore, if you had bothered to read one of the papers I linked to, you would have seen the claim that others, including NASA, have attempted to create the same effect. You can posture all you want on the internet, but if you make no serious attempt at research, why should I care what you think? I'm not saying you don't raise any good points at all (some were silly, also, but I don't want to spend the time pointing them out), but nothing you've written, here or at JREF, comes close to nailing this down. If you were a journalist, being paid good money to track down this story, is this how you'd proceed to determine whether it's true or whether it's a hoax?
If it's true that NASA tried to reproduce the PM work, isn't it a logical first step to contact them, and get their evaluation? Then, too, government agencies sometimes lie. So, a real journalist wouldn't stop with 1 negative report. Instead, he/she would would make numerous inquiries, of different parties, to find out who else may have attempted to reproduce this, and what their results were.
If I thought you were sincere, I'd give you yet another pointer as to how you could check this out, but I'm not going to bother. Since it's suggested by common sense, as a debunker gifted with stellar logic, you should be able to figure it out on your own, anyway.
Sometimes experiment leads theory and sometimes its the other way around. relativity is one example of theory leading experiment, and experiment has shown that the theory is correct in many of the predictions that follow from the theory.
So has NASA done experiments to try and manipulate gravity? Yes, they have done or sponsored such experiments. Have they attempted the same thing that Podkletnov has? No, they did not finish the experiments. What I do know is that if NASA had acheived what Podkletnov claims he has then it would have been front page news in such publications as Scientific American or Discover. Hey, in fact both of those publications have indeed had articles on gravity. Discover actually had an entire issue in which gravity was featured. It was a year or so ago. I might have the issue here somewhere but its probably gone to recycle by now.(the wife hates it when I let those things pile up). Spinning disks or cylinders can in fact display effects that can be attributed to frame dragging and explained by the general theory of relativity. This effect acts perpendicular to the effect Podkletnov says he acheived.
Hey, I'm just warning you that this really smells like a hoax to me metamars. If you want to send Podkletnov money for his research I won't even attempt to slow you down..
I'm not a journalist. So, IF I were a journalist I would want to interview Podkletnov in person or at least on the phone. I would ask for details of how his device works. Obviously he had some reason to create the device the way he did. I'd want that history. I'd take his statements to an actual physicist and get an opinion on it. Then I'd also ask another physicist. Best bet would be to have one of them specilaize in experimental physics and the other a more theoretical physicist. Most articles on controvertial physics contain statements from persons who agree with and those who disagree with said theory and often from someone else who is undecided. Finally I'd read the interviews he has done already. One was in Wired magazine about 10 years ago.
riiight! If they say Podkletnov is out-to-lunch or a huckster, its because they are lieing. Gotta love a logic in which one can simply dismiss any evidence contrary to what one wants to hear. Keep in mind that I WANT to know that gravity is being manipulated.
I am waiting for the earthshattering announcement from Podkletnov et al, because metamars, what he says he has accomplished would indeed be THE most important discovery in science, EVER! His statements concerning why he lanquishes in obscurity just don't wash IMO. He has a Ph.D. and thus is equiped to write a proper paper on his discovery and invite replication by others as did Pons and Fleishman. They too believed in their work but they at least did something about it.
Furthermore, if you had bothered to read one of the papers I linked to, you would have seen the claim that others, including NASA, have attempted to create the same effect. You can posture all you want on the internet, but if you make no serious attempt at research, why should I care what you think? I'm not saying you don't raise any good points at all (some were silly, also, but I don't want to spend the time pointing them out), but nothing you've written, here or at JREF, comes close to nailing this down. If you were a journalist, being paid good money to track down this story, is this how you'd proceed to determine whether it's true or whether it's a hoax?
If it's true that NASA tried to reproduce the PM work, isn't it a logical first step to contact them, and get their evaluation? Then, too, government agencies sometimes lie. So, a real journalist wouldn't stop with 1 negative report. Instead, he/she would would make numerous inquiries, of different parties, to find out who else may have attempted to reproduce this, and what their results were.
If I thought you were sincere, I'd give you yet another pointer as to how you could check this out, but I'm not going to bother. Since it's suggested by common sense, as a debunker gifted with stellar logic, you should be able to figure it out on your own, anyway.
Sometimes experiment leads theory and sometimes its the other way around. relativity is one example of theory leading experiment, and experiment has shown that the theory is correct in many of the predictions that follow from the theory.
So has NASA done experiments to try and manipulate gravity? Yes, they have done or sponsored such experiments. Have they attempted the same thing that Podkletnov has? No, they did not finish the experiments. What I do know is that if NASA had acheived what Podkletnov claims he has then it would have been front page news in such publications as Scientific American or Discover. Hey, in fact both of those publications have indeed had articles on gravity. Discover actually had an entire issue in which gravity was featured. It was a year or so ago. I might have the issue here somewhere but its probably gone to recycle by now.(the wife hates it when I let those things pile up). Spinning disks or cylinders can in fact display effects that can be attributed to frame dragging and explained by the general theory of relativity. This effect acts perpendicular to the effect Podkletnov says he acheived.
Hey, I'm just warning you that this really smells like a hoax to me metamars. If you want to send Podkletnov money for his research I won't even attempt to slow you down..
I'm not a journalist. So, IF I were a journalist I would want to interview Podkletnov in person or at least on the phone. I would ask for details of how his device works. Obviously he had some reason to create the device the way he did. I'd want that history. I'd take his statements to an actual physicist and get an opinion on it. Then I'd also ask another physicist. Best bet would be to have one of them specilaize in experimental physics and the other a more theoretical physicist. Most articles on controvertial physics contain statements from persons who agree with and those who disagree with said theory and often from someone else who is undecided. Finally I'd read the interviews he has done already. One was in Wired magazine about 10 years ago.
QUOTE
Then, too, government agencies sometimes lie.
riiight! If they say Podkletnov is out-to-lunch or a huckster, its because they are lieing. Gotta love a logic in which one can simply dismiss any evidence contrary to what one wants to hear. Keep in mind that I WANT to know that gravity is being manipulated.
I am waiting for the earthshattering announcement from Podkletnov et al, because metamars, what he says he has accomplished would indeed be THE most important discovery in science, EVER! His statements concerning why he lanquishes in obscurity just don't wash IMO. He has a Ph.D. and thus is equiped to write a proper paper on his discovery and invite replication by others as did Pons and Fleishman. They too believed in their work but they at least did something about it.
Hmfff.
Conspiracy theorists.
Sandra
Conspiracy theorists.
Sandra
QUOTE (metamars+Apr 20 2008, 04:56 PM)
LaViolette is coming out with a book on exotic propulsion. I think I can reasonably guess that if the book is mostly true, exotic devices that may have worked similarly to the Podkletnov device, but much more powerful, were already developed on 9/11.
Some inconsistencies in at least one of LaViolette propositions.
This is the basis for the above claim.
Yes, very odd then that anyone would put an over unity efficient propulsion system that only works at superconic speeds when that craft is not capable of reaching mach 1
The max speed of B2 is 470 MPH
'wait for it,,,,,, 3...2...1 metamars posts "yeah, that's what they want you to believe"
We also diverge from the thread topic in that metamars has not been able to show that such beam exists let alone that it exists on the scale required to lay down a smacking on three office buildings.
QUOTE
Excerpt from "The U.S. Antigravity Squadron"
by Paul A. LaViolette, Ph.D.
Electrogravitic (antigravity) technology, under development in U.S. Air Force black R&D programs since late 1954, may now have been put to practical use in the B-2 Advanced Technology Bomber to provide an exotic auxiliary mode of propulsion. This inference is based on the recent disclosure that the B-2 charges both its wing leading edge and jet exhaust stream to a high voltage. Positive ions emitted from its wing leading edge would produce a positively charged parabolic ion sheath ahead of the craft while negative ions injected into it's exhaust stream would set up a trailing negative space charge with a potential difference in excess of 15 million volts. According to electrogravitic research carried out by physicist T. Townsend Brown, such a differential space charge would set up an artificial gravity field that would induce a reactionless force on the aircraft in the direction of the positive pole. An electrogravitic drive of this sort could allow the B-2 to function with over-unity propulsion efficiency when cruising at supersonic velocities.
http://www.etheric.com/LaVioletteBooks/Book-ES.html
The B-2 stealth bomber is designed to fly at subsonic speeds to avoid the shock wave propagation(sonic boom) associated with supersonic flight that would tend to reduce it's stealthiness. by Paul A. LaViolette, Ph.D.
Electrogravitic (antigravity) technology, under development in U.S. Air Force black R&D programs since late 1954, may now have been put to practical use in the B-2 Advanced Technology Bomber to provide an exotic auxiliary mode of propulsion. This inference is based on the recent disclosure that the B-2 charges both its wing leading edge and jet exhaust stream to a high voltage. Positive ions emitted from its wing leading edge would produce a positively charged parabolic ion sheath ahead of the craft while negative ions injected into it's exhaust stream would set up a trailing negative space charge with a potential difference in excess of 15 million volts. According to electrogravitic research carried out by physicist T. Townsend Brown, such a differential space charge would set up an artificial gravity field that would induce a reactionless force on the aircraft in the direction of the positive pole. An electrogravitic drive of this sort could allow the B-2 to function with over-unity propulsion efficiency when cruising at supersonic velocities.
http://www.etheric.com/LaVioletteBooks/Book-ES.html
This is the basis for the above claim.
QUOTE (->
| QUOTE |
| Excerpt from "The U.S. Antigravity Squadron" by Paul A. LaViolette, Ph.D. Electrogravitic (antigravity) technology, under development in U.S. Air Force black R&D programs since late 1954, may now have been put to practical use in the B-2 Advanced Technology Bomber to provide an exotic auxiliary mode of propulsion. This inference is based on the recent disclosure that the B-2 charges both its wing leading edge and jet exhaust stream to a high voltage. Positive ions emitted from its wing leading edge would produce a positively charged parabolic ion sheath ahead of the craft while negative ions injected into it's exhaust stream would set up a trailing negative space charge with a potential difference in excess of 15 million volts. According to electrogravitic research carried out by physicist T. Townsend Brown, such a differential space charge would set up an artificial gravity field that would induce a reactionless force on the aircraft in the direction of the positive pole. An electrogravitic drive of this sort could allow the B-2 to function with over-unity propulsion efficiency when cruising at supersonic velocities. http://www.etheric.com/LaVioletteBooks/Book-ES.html |
The B-2 stealth bomber is designed to fly at subsonic speeds to avoid the shock wave propagation(sonic boom) associated with supersonic flight that would tend to reduce it's stealthiness.
This is the basis for the above claim.On March 9, 1992, Aviation Week and Space Technology magazine made a surprising disclosure that the B-2 electrostatically charges its exhaust stream and the leading edges of its wing-like body
This is the basis for the above claim.On March 9, 1992, Aviation Week and Space Technology magazine made a surprising disclosure that the B-2 electrostatically charges its exhaust stream and the leading edges of its wing-like body
I could not find the article mentioned to verify the claim, but if there is any substance to the claim, it may have to do with the intended stealth characteristics of the bomber, and not exotic propulsion.
QUOTE
Plasma stealth is a proposed process that uses ionized gas (plasma) to reduce the radar cross section (RCS) of an aircraft. Interactions between electromagnetic radiation and ionized gas have been extensively studied for a variety of purposes, including the possible concealment of aircraft from radar that plasma stealth theorizes. While it is theoretically possible to reduce an aircraft's RCS by wrapping the airframe in plasma, it may be very difficult to do so in practice. Various methods might plausibly be able to produce a layer or cloud of plasma around an airframe, from "simple" electrostatic or RF discharges to more exotic possibilities like laser-produced plasmas.
http://en.wikipedia.org/wiki/Plasma_stealth
http://en.wikipedia.org/wiki/Plasma_stealth
QUOTE
An electrogravitic drive of this sort could allow the B-2 to function with over-unity propulsion efficiency when cruising at supersonic velocities.
Yes, very odd then that anyone would put an over unity efficient propulsion system that only works at superconic speeds when that craft is not capable of reaching mach 1
The max speed of B2 is 470 MPH
'wait for it,,,,,, 3...2...1 metamars posts "yeah, that's what they want you to believe"
We also diverge from the thread topic in that metamars has not been able to show that such beam exists let alone that it exists on the scale required to lay down a smacking on three office buildings.
Still going, I see. 
yes indeed 555, but it looks like it hasn't the highest priority at the moment (there is more in life than 911...) but in fact there is so much to do that one even has no idea where to start!
Einsteen:
This thread is never-ending because there will always be just one more question....
This thread is never-ending because there will always be just one more question....
Like the natural numbers, there is no highest one...
I just was reading the Heiwa thread and you asked him the same questions again.
Do you know what the problem is dr Greening, in my opinion the collapses of the two towers
(although very different than wtc7) are related with the collapse of that third building, if that
collapse is a controlled demolition then I don't think it is stupid to question the other buildings
also. Wtc7's collapse is really strange and I really can't believe how nonchalantly people treat that biding, like it is nothing, like a footnote, like it is to be expected, it was a big major event although overshadowed by the twin towers. I also don't think I understand your position, when speaking with CT'ers like Heiwa for example you think they believe in crap, when speaking with JREF'ers you call them NISTians or mention that NIST's work is not scientific, wtc7s report will never be published and you even had a period that you thought rocket fuel was in the towers without a working theory.
I remember that my dad called me on 9/11 (I had a free day) and I turned the TV on saw the silhouette of a plane in the building, I went to my parents house to watch TV there and I heard that the towers collapsed. I thought how is that possible? I always found it very 'unnatural' but I accepted it, but now since I heard about wtc7 and all alternative theories I can't get it out of my mind although I'm absolutely a sceptical individual who is never affected by other people. I even was ashamed in the beginning even to question the official story. If I now watch the collapses I think, how obvious is it that this could never occur.
Why is it impossible to place devices in buildings? You place them one by one. Politically impossible but not physically. Let's assume that they were placed in/at the core columns only. Could those isolated devices survive jet fire? Some JREF'ers even believe that pools of fuel could survive the jet fuel. But the question assumes they did survive, which is not needed.
What is destroyed by the impact is gone already and if core columns survived why couldn't devices survive? And what do you expect to find in two times 300,000 tons of rubble, who is going to look for those devices, that has no priority, you don’t look for it and you want to have your town clean, it is a typical JREF straw man to think that people have to be ‘in on it’,
And you asked about that detonator button... why waiting 56 and 102 minutes... if you put your CT hat on that is easy to answer. First of all you need sufficient time to get camera teams there because only the Naudet Bros were there on scene. The show must be a Hollywood-like big one, everyone must see it and it will be repeated endlessly. And the ratio of 102 and 56 is related with the height of impact, that could easily be measured in that time. And wtc7, the most plausible one that I've heard is that it had to go in the shadow of wtc1's collapse, which didn’t happen. This raises the question why they are at the one hand very competent but on the other hand make such a stupid mistake. That's a good question, but we don't have all answers. If you, for example, can't find a motive for the death of a good, healthy and young person then why would you think it is a natural death?
I just was reading the Heiwa thread and you asked him the same questions again.
Do you know what the problem is dr Greening, in my opinion the collapses of the two towers
(although very different than wtc7) are related with the collapse of that third building, if that
collapse is a controlled demolition then I don't think it is stupid to question the other buildings
also. Wtc7's collapse is really strange and I really can't believe how nonchalantly people treat that biding, like it is nothing, like a footnote, like it is to be expected, it was a big major event although overshadowed by the twin towers. I also don't think I understand your position, when speaking with CT'ers like Heiwa for example you think they believe in crap, when speaking with JREF'ers you call them NISTians or mention that NIST's work is not scientific, wtc7s report will never be published and you even had a period that you thought rocket fuel was in the towers without a working theory.
I remember that my dad called me on 9/11 (I had a free day) and I turned the TV on saw the silhouette of a plane in the building, I went to my parents house to watch TV there and I heard that the towers collapsed. I thought how is that possible? I always found it very 'unnatural' but I accepted it, but now since I heard about wtc7 and all alternative theories I can't get it out of my mind although I'm absolutely a sceptical individual who is never affected by other people. I even was ashamed in the beginning even to question the official story. If I now watch the collapses I think, how obvious is it that this could never occur.
Why is it impossible to place devices in buildings? You place them one by one. Politically impossible but not physically. Let's assume that they were placed in/at the core columns only. Could those isolated devices survive jet fire? Some JREF'ers even believe that pools of fuel could survive the jet fuel. But the question assumes they did survive, which is not needed.
What is destroyed by the impact is gone already and if core columns survived why couldn't devices survive? And what do you expect to find in two times 300,000 tons of rubble, who is going to look for those devices, that has no priority, you don’t look for it and you want to have your town clean, it is a typical JREF straw man to think that people have to be ‘in on it’,
And you asked about that detonator button... why waiting 56 and 102 minutes... if you put your CT hat on that is easy to answer. First of all you need sufficient time to get camera teams there because only the Naudet Bros were there on scene. The show must be a Hollywood-like big one, everyone must see it and it will be repeated endlessly. And the ratio of 102 and 56 is related with the height of impact, that could easily be measured in that time. And wtc7, the most plausible one that I've heard is that it had to go in the shadow of wtc1's collapse, which didn’t happen. This raises the question why they are at the one hand very competent but on the other hand make such a stupid mistake. That's a good question, but we don't have all answers. If you, for example, can't find a motive for the death of a good, healthy and young person then why would you think it is a natural death?
Einsteen:
Well, that's a lot of points to address, but let me try to cover some at least ...... First let me say I do not see that I have been inconsistent in the position I have taken on the issues I have addressed in my posts over the past two years. Sure, I have many problems with some parts of the NIST Report but that does NOT mean I see conspiracies behind the collapse of WTC 1 & 2. Just a lot of things NIST did not address, like the collapse times themselves, chemical effects in the fires, the tipping of the upper sections, etc, etc. And its too bad NIST did not address the pulverization of the concrete and the high temperatures in the rubble piles. So I get a little annoyed at the JREFers who think the NIST Report is somehow flawless and complete - the gospel according to a bunch of fire-safety engineers - hence I call the true believers over at JREF: "NISTIANS". And by the way, I HAVE written to the NIST several times about some concerns I have about its WTC Report and have been ignored every time; c'est la vie!
And Einsteen, I HAVE thought long and hard about the conspiracy theories I have read about on sites like LooseChange, LetsRoll, or 911Blogger, and I have BIG problems with all of them. That's why I came up with my very own conspiracy theory - ammonium perchlorate in the sprayed-on thermal insulation - to emphasize how easy it is to create wild and crazy ideas about what happened to the Twin Towers if you let your imagination run wild. And I circulated that particular theory just to show that ANYONE can PROPOSE a conspiracy theory, but that does not mean it happened that way. You need proof!
So let's talk about pre-planted explosives. I think it is just not on! Not with aircraft slamming into the towers at 500 mph. No one would try a kamikaze attack on the Twin Towers AND a CD. The Japanese knew better than that. They loaded the aircraft with explosives! But let's assume there were pre-planted explosives in WTC 1 & 2 and SOME explosives did miraculously survive the aircraft impacts, then I have to ask you: how did these shock-resistant explosives survive the subsequent fires? Would you throw a stick of dynamite into a fire and expect it not to explode?!?!
Einsteen, did you ever wonder why Heiwa will not discuss HIS theory of how the Towers fell? No, he just says, without proof, that the collapses should have been arrested. (Sounds like he's been talking to Gordon Ross!) But Heiwa offers no real calculations, just arrogant assertions that he knows best and the rest of us are stupid morons! But if Heiwa really believes that a gravity-driven collapse was impossible he needs to explain how it was done by a CD. A CD that starts in the fire-ravaged impact zones of each tower.....
Well, that's a lot of points to address, but let me try to cover some at least ...... First let me say I do not see that I have been inconsistent in the position I have taken on the issues I have addressed in my posts over the past two years. Sure, I have many problems with some parts of the NIST Report but that does NOT mean I see conspiracies behind the collapse of WTC 1 & 2. Just a lot of things NIST did not address, like the collapse times themselves, chemical effects in the fires, the tipping of the upper sections, etc, etc. And its too bad NIST did not address the pulverization of the concrete and the high temperatures in the rubble piles. So I get a little annoyed at the JREFers who think the NIST Report is somehow flawless and complete - the gospel according to a bunch of fire-safety engineers - hence I call the true believers over at JREF: "NISTIANS". And by the way, I HAVE written to the NIST several times about some concerns I have about its WTC Report and have been ignored every time; c'est la vie!
And Einsteen, I HAVE thought long and hard about the conspiracy theories I have read about on sites like LooseChange, LetsRoll, or 911Blogger, and I have BIG problems with all of them. That's why I came up with my very own conspiracy theory - ammonium perchlorate in the sprayed-on thermal insulation - to emphasize how easy it is to create wild and crazy ideas about what happened to the Twin Towers if you let your imagination run wild. And I circulated that particular theory just to show that ANYONE can PROPOSE a conspiracy theory, but that does not mean it happened that way. You need proof!
So let's talk about pre-planted explosives. I think it is just not on! Not with aircraft slamming into the towers at 500 mph. No one would try a kamikaze attack on the Twin Towers AND a CD. The Japanese knew better than that. They loaded the aircraft with explosives! But let's assume there were pre-planted explosives in WTC 1 & 2 and SOME explosives did miraculously survive the aircraft impacts, then I have to ask you: how did these shock-resistant explosives survive the subsequent fires? Would you throw a stick of dynamite into a fire and expect it not to explode?!?!
Einsteen, did you ever wonder why Heiwa will not discuss HIS theory of how the Towers fell? No, he just says, without proof, that the collapses should have been arrested. (Sounds like he's been talking to Gordon Ross!) But Heiwa offers no real calculations, just arrogant assertions that he knows best and the rest of us are stupid morons! But if Heiwa really believes that a gravity-driven collapse was impossible he needs to explain how it was done by a CD. A CD that starts in the fire-ravaged impact zones of each tower.....
einsteen --- Alan (the ex-elevator man) currently does building maintenance in a tall building. He has posted several times of the physical impossibility of placing explosives without being caught.
This is equally true for WTC 7 as for WTC 1 & 2.
This is equally true for WTC 7 as for WTC 1 & 2.
ever heard of "in toto", neu-fonze?
prove that?
better to burn out than fade away, dude.
YOU could make a GOOD historical mark.
we didn't need the spray on rocket fuel "ad absurdum" argument. we already had the nineteen hijackers one.
prove that?
better to burn out than fade away, dude.
YOU could make a GOOD historical mark.
we didn't need the spray on rocket fuel "ad absurdum" argument. we already had the nineteen hijackers one.
newton
Grumpy 
QUOTE
Luke...come to the Dark side...
Grumpy
I agree that Heiwa should use a more mathematical approach. If I look at his resume the man seems really a qualified engineer and no armchairer like a lot of CT'ers (like me...). I've not really read his pages but I can understand some of his problems.
Would you throw a stick of dynamite into a fire and expect it not to explode?!?!
Lol, perhaps a stick with fire-proofing
Would you throw a stick of dynamite into a fire and expect it not to explode?!?!
Lol, perhaps a stick with fire-proofing
QUOTE (metamars+Apr 23 2008, 12:34 PM)
I wrote the following to Podkletnov, via email:
I posted additional correspondence with Podkletnov at JREF.
From my email correspondence with Podkletnov, it appears that he cannot produce, in his current location in Finland, either the weaker pendulum effect or the more dramatic concrete effect. It's beyond me why he wouldn't seek a modest amount of funding, first, to reproduce at least the weaker effect, away from the control of the Russian government (where his experiments that showed these effects took place). I wonder if he understands how venture capitalists think.
Also, I wrote an email to Modanese asking if he had witnessed the pendulum effect, but got no reply.
Finally, via email correspondence with LaViolette, he states that superconductors are not necessary to demonstrate the gravity thrust effects of Coulomb wave shocks, and he furthermore estimates that it could be done with about $300,000.
I posted additional correspondence with Podkletnov at JREF.
From my email correspondence with Podkletnov, it appears that he cannot produce, in his current location in Finland, either the weaker pendulum effect or the more dramatic concrete effect. It's beyond me why he wouldn't seek a modest amount of funding, first, to reproduce at least the weaker effect, away from the control of the Russian government (where his experiments that showed these effects took place). I wonder if he understands how venture capitalists think.
Also, I wrote an email to Modanese asking if he had witnessed the pendulum effect, but got no reply.
Finally, via email correspondence with LaViolette, he states that superconductors are not necessary to demonstrate the gravity thrust effects of Coulomb wave shocks, and he furthermore estimates that it could be done with about $300,000.
Does anybody have any hot scoops re the 2008 Structures Conference? It took place last month, and dealt partly with progressive collapse.
===================================
There will be 3 presentations on Progressive Collapse:
http://www.succeed.ufl.edu/asce08/schedule_day.asp
The competition was described here:
http://www.boston.com/news/science/article...ings_fall_down/
===================================
There will be 3 presentations on Progressive Collapse:
http://www.succeed.ufl.edu/asce08/schedule_day.asp
The competition was described here:
http://www.boston.com/news/science/article...ings_fall_down/
QUOTE (metamars+May 8 2008, 07:07 PM)
There will[were?] be 3 presentations on Progressive Collapse:
Thanks for posting this.
The abstract of 'pushdown analysis' was of particular interest.
Thanks for posting this.
The abstract of 'pushdown analysis' was of particular interest.
QUOTE (David B. Benson+May 9 2008, 05:46 PM)
Thanks for posting this.
The abstract of 'pushdown analysis' was of particular interest.
You're welcome. Please post if you find out where they will publish.
The abstract of 'pushdown analysis' was of particular interest.
You're welcome. Please post if you find out where they will publish.
Sorry for spamming the thread, but I have a problem, I did a test and I'm wondering about these two
questions (which I translate in English and using no words)
1. no A are V - all F are A
A. no F are V
B. some A are no F
C. no V are A
D. no conclusion possible
2. all H are P - some R are H
A. some P are R
B. some R are P
C. geen P are Rs
D. no conclusion possible
The answers seem to be
1A
2B
I got them wrong, I always draw diagrams with collections etc and I would say that
1C is also true and 2B is identical to 2A.
Such an answer is wrong or right, why is the other one more right than the other ?
Thanks in advance...
questions (which I translate in English and using no words)
1. no A are V - all F are A
A. no F are V
B. some A are no F
C. no V are A
D. no conclusion possible
2. all H are P - some R are H
A. some P are R
B. some R are P
C. geen P are Rs
D. no conclusion possible
The answers seem to be
1A
2B
I got them wrong, I always draw diagrams with collections etc and I would say that
1C is also true and 2B is identical to 2A.
Such an answer is wrong or right, why is the other one more right than the other ?
Thanks in advance...
QUOTE (einsteen+May 10 2008, 08:39 PM)
Sorry for spamming the thread, but I have a problem, I did a test and I'm wondering about these two
questions (which I translate in English and using no words)
1. no A are V - all F are A
A. no F are V
B. some A are no F
C. no V are A
D. no conclusion possible
2. all H are P - some R are H
A. some P are R
B. some R are P
C. geen P are Rs
D. no conclusion possible
The answers seem to be
1A
2B
I got them wrong, I always draw diagrams with collections etc and I would say that
1C is also true and 2B is identical to 2A.
Such an answer is wrong or right, why is the other one more right than the other ?
Thanks in advance...
Hiya, einsteen! I'll take a stab using some BS notation I made up with the idea of it reading the same way as the appropriate formalism. Diagrams can lead to trouble!
Part one:
- x elementOf A implies x NOT elementOf V
- x elementOf F implies x elementOf A
A) by transitivity, x elementOf F implies x elementOf A implies x NOT elementOf V. So this is definitely true.
B) thereExists x suchthat x elementOf A implies x NOT elementOf F. Could be false if A isEquivalentTo F.
C) forAll x, x elementOf V implies x NOT elementOf A
This is a good one. I pretty much agree with you, einsteen, except there appears to be one loophole. The fact that no A are V means sets A and V are disjoint UNLESS V is the empty set, which does not seem to violate the second given. So, your diagram is right but V could be null.
I have to make some drinks and I'll be back for part 2.
questions (which I translate in English and using no words)
1. no A are V - all F are A
A. no F are V
B. some A are no F
C. no V are A
D. no conclusion possible
2. all H are P - some R are H
A. some P are R
B. some R are P
C. geen P are Rs
D. no conclusion possible
The answers seem to be
1A
2B
I got them wrong, I always draw diagrams with collections etc and I would say that
1C is also true and 2B is identical to 2A.
Such an answer is wrong or right, why is the other one more right than the other ?
Thanks in advance...
Hiya, einsteen! I'll take a stab using some BS notation I made up with the idea of it reading the same way as the appropriate formalism. Diagrams can lead to trouble!
Part one:
- x elementOf A implies x NOT elementOf V
- x elementOf F implies x elementOf A
A) by transitivity, x elementOf F implies x elementOf A implies x NOT elementOf V. So this is definitely true.
B) thereExists x suchthat x elementOf A implies x NOT elementOf F. Could be false if A isEquivalentTo F.
C) forAll x, x elementOf V implies x NOT elementOf A
This is a good one. I pretty much agree with you, einsteen, except there appears to be one loophole. The fact that no A are V means sets A and V are disjoint UNLESS V is the empty set, which does not seem to violate the second given. So, your diagram is right but V could be null.
I have to make some drinks and I'll be back for part 2.
Set theory is cool, but it's not my bag so I may be on the wrong track. It seems to me that this one also hinges on whether or not any of these sets are empty sets.
A - possible if R non-empty but false if it is
B - always true
C - possible if R empty but false if it isn't
The fact that additional qualifiers are required for A and C would lead me to choose B which can be evaluated to be true with the givens. The problem with the diagram is that you must remember that a circle, in this case, could also be nothing.
A - possible if R non-empty but false if it is
B - always true
C - possible if R empty but false if it isn't
The fact that additional qualifiers are required for A and C would lead me to choose B which can be evaluated to be true with the givens. The problem with the diagram is that you must remember that a circle, in this case, could also be nothing.
QUOTE (einsteen+May 10 2008, 08:39 PM)
Sorry for spamming the thread, . . .
Did you get my PM?
Did you get my PM?
Meta, Replied.
OneWhiteEye, thanks, I'll check it out in detail later, I'm visiting my family now.
In other of those questions it seems that there is a difference between "at least some A or B" or "some A or B" because the first could also mean that "all A are B"
I have a interview for a new job Friday (which means bad sleeping although I've nothing to lose) and it seems that they give those capacity tests, it really is possible to train those tests and I need to do that because my IQ has dropped 30 points compared with 8 years ago... too much conspiracy theories I guess.... most of those insulting tests are easy, those stupid shapes etc, but the only factor is time, by the definition of those tests your intelligence is the question how fast you can answer some simple questions. But that seems a little bit strange because you could program a computer to solve things like 1,3,5,7, the algorithm is always a sum, a difference, sometimes the square etc and sometimes they skip and a computer could solve 10,000 of those things in a second without an error, but are computers smart ? Of course those tests say anything but not much IMHO. Do you have any tips...I know that in the USA it seems to be even more important than here.
OneWhiteEye, thanks, I'll check it out in detail later, I'm visiting my family now.
In other of those questions it seems that there is a difference between "at least some A or B" or "some A or B" because the first could also mean that "all A are B"
I have a interview for a new job Friday (which means bad sleeping although I've nothing to lose) and it seems that they give those capacity tests, it really is possible to train those tests and I need to do that because my IQ has dropped 30 points compared with 8 years ago... too much conspiracy theories I guess.... most of those insulting tests are easy, those stupid shapes etc, but the only factor is time, by the definition of those tests your intelligence is the question how fast you can answer some simple questions. But that seems a little bit strange because you could program a computer to solve things like 1,3,5,7, the algorithm is always a sum, a difference, sometimes the square etc and sometimes they skip and a computer could solve 10,000 of those things in a second without an error, but are computers smart ? Of course those tests say anything but not much IMHO. Do you have any tips...I know that in the USA it seems to be even more important than here.
I don't want to give you the impression that I answered those as quick as I could write the posts. I sat down with paper for 10-15 minutes before answering. What's more, I'm probably wrong. If I were the one doing the test, I'd take a wild-*** guess and move on. And have a better chance of being right than if I'd thought about it.
Smarter than your average bear.
Smarter than your average bear.
Do you have any tips?
Avoid this employer like the plague. Somehow they've come to the conclusion that these tests count for something, and they don't. Reminds me of Mensa. No offense if there are any members here, but I'm utterly unimpressed. I saw one of their 'clever' little quizzes on the back of a cereal box, of all places. That should say it all. The few people I've known in this group can answer questions like this in their sleep but cannot seem to function on any level outside the world of carefully crafted stupid questions. Wouldn't hire one if you put a gun to my head.
Maybe. I think usually these sorts of tests are administered to wannabe hardware store managers and food servers. I did get quite a grilling a few years back on technical minutiae in my field (and found an error in the test! that got me the job), but this was the only pre-employment test I've been given since the days of minimum wage jobs between school sessions.
I needed some relaxing reading so I've just picked up "Denotational Semantics for 'Natural' Language Question-Answering Programs"... something tells me DBB can answer these questions. Funny, I may have read this paper 25 years ago, it would be about the time this sort of thing was of interest to me. Small world.
Well. This is my 500th post. I shouldn't squander it, need to say something important and on-topic. Hmmm. Uhhh.
Overwhelmed as one would be, placed in my position.
Such a heavy burden now to be the One
Born to bear and bring to all the details of our ending,
To write it down for all the world to see.
But I forgot my pen...
QUOTE
...but are computers smart ?
Smarter than your average bear.
QUOTE (->
| QUOTE |
| ...but are computers smart ? |
Smarter than your average bear.
Do you have any tips?
Avoid this employer like the plague. Somehow they've come to the conclusion that these tests count for something, and they don't. Reminds me of Mensa. No offense if there are any members here, but I'm utterly unimpressed. I saw one of their 'clever' little quizzes on the back of a cereal box, of all places. That should say it all. The few people I've known in this group can answer questions like this in their sleep but cannot seem to function on any level outside the world of carefully crafted stupid questions. Wouldn't hire one if you put a gun to my head.
QUOTE
I know that in the USA it seems to be even more important than here.
Maybe. I think usually these sorts of tests are administered to wannabe hardware store managers and food servers. I did get quite a grilling a few years back on technical minutiae in my field (and found an error in the test! that got me the job), but this was the only pre-employment test I've been given since the days of minimum wage jobs between school sessions.
I needed some relaxing reading so I've just picked up "Denotational Semantics for 'Natural' Language Question-Answering Programs"... something tells me DBB can answer these questions. Funny, I may have read this paper 25 years ago, it would be about the time this sort of thing was of interest to me. Small world.
Well. This is my 500th post. I shouldn't squander it, need to say something important and on-topic. Hmmm. Uhhh.
Overwhelmed as one would be, placed in my position.
Such a heavy burden now to be the One
Born to bear and bring to all the details of our ending,
To write it down for all the world to see.
But I forgot my pen...
Probably the tests will not be of this level, when they only ask if it is wrong or right then they are easy to make, if they give me a piece of paper, I had a quick look at your explanation and think the key is indeed in the empty sets. I asked an old friend from university, he said that both 1a and 1c are true, but 1a is the direct simple conclusion from combining the statements. But I think I stop with preparing those tests because it only gives you stress... Avoiding like the plague... I know what you mean, I also was amazed that that manager called me about those tests because they asked me to work for them, I didn't apply. But he also said that if you don't pass the test the whole procedure stops. When I started at a bank (after university) I also had such an assessment BS day, I don't like it., but it seems you can't always avoid it. Enough spam for now...
QUOTE (einsteen+May 10 2008, 01:39 PM)
1. no A are V - all F are A
[A -> -V; F -> A]
A. no F are V
[F -> -V]
B. some A are no F
[A & -F]
C. no V are A
[V -> -A]
D. no conclusion possible
2. all H are P - some R are H
[H -> P; R & H]
A. some P are R
[P & R]
B. some R are P
[R & P]
C. geen P are Rs
??
D. no conclusion possible
Notation: A -> B means 'A implies B'; -A means 'not A; A v B means 'A or B'; A & B means 'A and B'.
1A. Proof: F -> A -> -V
1B. No proof or disproof possible, since we don't know whether or not A -> F.
1C. Proof: V -> -A == -V v -A == A -> -V. [Classical logic only, no proof (that I know of) in intuitionistic (constructivist) logic.]
2A&2B (being the same). Proof: R & H -> R & P
[A -> -V; F -> A]
A. no F are V
[F -> -V]
B. some A are no F
[A & -F]
C. no V are A
[V -> -A]
D. no conclusion possible
2. all H are P - some R are H
[H -> P; R & H]
A. some P are R
[P & R]
B. some R are P
[R & P]
C. geen P are Rs
??
D. no conclusion possible
Notation: A -> B means 'A implies B'; -A means 'not A; A v B means 'A or B'; A & B means 'A and B'.
1A. Proof: F -> A -> -V
1B. No proof or disproof possible, since we don't know whether or not A -> F.
1C. Proof: V -> -A == -V v -A == A -> -V. [Classical logic only, no proof (that I know of) in intuitionistic (constructivist) logic.]
2A&2B (being the same). Proof: R & H -> R & P
thanks David, you say that 2a,b are the same... if I get such a question and I don't pass the test I will refer them to you..
Buildings have tested a stretching, that, usually, is not considered at designing.
David S. Chandler uses a physics toolkit to calculate some ejections etc of the towers,
anyone seen it ?
http://www.youtube.com/watch?v=B9YjireIPCQ
He also uses the kit to measure wtc7's acceleration
http://www.youtube.com/watch?v=POUSJm--tgw
47 views only, the only thing he forgot is the camera angle, but that will
not change much at that position.
anyone seen it ?
http://www.youtube.com/watch?v=B9YjireIPCQ
He also uses the kit to measure wtc7's acceleration
http://www.youtube.com/watch?v=POUSJm--tgw
47 views only, the only thing he forgot is the camera angle, but that will
not change much at that position.
einsteen, you are from Holland aren't you?
Did you see the Delft university building fire/partial collapse?
Video with partial collapse:
http://dumpert.nl/mediabase/105731/46ccb8c...t_stort_in.html
Building afterwards.
User posted image: User posted image
Yet another situation where the crush-down model doesn't apply...
Did you see the Delft university building fire/partial collapse?
Video with partial collapse:
http://dumpert.nl/mediabase/105731/46ccb8c...t_stort_in.html
Building afterwards.
User posted image: User posted image
Yet another situation where the crush-down model doesn't apply...
Yes...
Yeah, the faculty architecture...
Look at the flame-hell
http://www.nufoto.nl/2008/05/13/vlammenhel/
and a bigger resolution from the collapse
http://www.nufoto.nl/2008/05/13/weinig-over-van-bouwkunde/
Yeah, the faculty architecture...
Look at the flame-hell
http://www.nufoto.nl/2008/05/13/vlammenhel/
and a bigger resolution from the collapse
http://www.nufoto.nl/2008/05/13/weinig-over-van-bouwkunde/
Lends a modicum of credence to Gordon Ross's arrested collapse hypothesis.
einsteen: have you seen any of these, "flying" down the boulevard?
From the mind of the Dutch:
http://www.flytheroad.com/
einsteen: have you seen any of these, "flying" down the boulevard?
From the mind of the Dutch:
http://www.flytheroad.com/
einsteen
Are you attempting to say that the Dutch collapse says something about the towers? It sure looks like the steel structure collapsed due to heat to me. The concrete core didn't, but then the towers didn't have any concrete in the core walls. The video actually provides support for the progressive collapse of the towers steel structure.
Grumpy
Are you attempting to say that the Dutch collapse says something about the towers? It sure looks like the steel structure collapsed due to heat to me. The concrete core didn't, but then the towers didn't have any concrete in the core walls. The video actually provides support for the progressive collapse of the towers steel structure.
Grumpy
Hi guys, i have a question for you all. Could someone calculate the forces needed for the plane to penetrate the outer shell of the WTC? I know it has to do with the kinetic energy, but i can't get a grip on the calculation.
QUOTE (Jay38+May 15 2008, 09:25 PM)
Hi guys, i have a question for you all. Could someone calculate the forces needed for the plane to penetrate the outer shell of the WTC? I know it has to do with the kinetic energy, but i can't get a grip on the calculation.
Suss suss..quiet !! Dont think about that.
But here are two men who did some calculation. But they dont tell the whole story. They dont have any floors in the test structure ! And more problem with theirs analysis.
"It was found that about 46% of the initial kinetic energy of the aircraft was used to damage columns. The minimum impact velocity of the aircraft to just penetrate the exterior columns would be 130 m/s. It was also found that a Boeing 767 traveling at top speed would not penetrate exterior columns of the WTC if the columns were thicker than 20 mm."Impact of the Boeing 767 Aircraft into the World Trade Center (click on the pdf)
But I can tell you that it is not possible for B767 to fully penitrate wtc totally intact ! and simply vanish inside the tower... and then suddenly explode ! I repeat: NOT possible. You would see some random damage, maybe the engines would penetrate (maybe) But what would not happen is what the videos of the impact shows. What will happen when a plane crash against massive steel and concrete structure like wtc is... a crash ! You will see the plane crash against the structure.
Suss suss..quiet !! Dont think about that.
But here are two men who did some calculation. But they dont tell the whole story. They dont have any floors in the test structure ! And more problem with theirs analysis.
"It was found that about 46% of the initial kinetic energy of the aircraft was used to damage columns. The minimum impact velocity of the aircraft to just penetrate the exterior columns would be 130 m/s. It was also found that a Boeing 767 traveling at top speed would not penetrate exterior columns of the WTC if the columns were thicker than 20 mm."Impact of the Boeing 767 Aircraft into the World Trade Center (click on the pdf)
But I can tell you that it is not possible for B767 to fully penitrate wtc totally intact ! and simply vanish inside the tower... and then suddenly explode ! I repeat: NOT possible. You would see some random damage, maybe the engines would penetrate (maybe) But what would not happen is what the videos of the impact shows. What will happen when a plane crash against massive steel and concrete structure like wtc is... a crash ! You will see the plane crash against the structure.
Jay38:
If we assume that the entire aircraft was completely stopped by the impact with the tower then the work done by the aircraft in entering a tower will be approximately equal to the kinetic energy of the aircraft.
Work = Force x distance, and in this case the distance would be the length of the aircraft.
Hence,
Force x L = 1/2 M. v^2
where L is the length of the aircraft, M is the mass of the aircraft, v is the velocity of the aircraft.
Substituting some values:
L = 50 meters
M = 125 tonnes
v = 200 m/s
Force x 50 = 1/2 x 125,000 x (200)^2
Force = 50 x 10^6 Newtons or 50 MN
NIST NCSTAR 1-5D gives an estimated value for the force acting on WTC 2 from the aircraft impact as peaking at 75 MN. NIST show the force as declining uniformly to zero over a period of 0.6 seconds. Hence the average force would be 37.5 MN in reasonable agreement with the approximate calculation.
If we assume that the entire aircraft was completely stopped by the impact with the tower then the work done by the aircraft in entering a tower will be approximately equal to the kinetic energy of the aircraft.
Work = Force x distance, and in this case the distance would be the length of the aircraft.
Hence,
Force x L = 1/2 M. v^2
where L is the length of the aircraft, M is the mass of the aircraft, v is the velocity of the aircraft.
Substituting some values:
L = 50 meters
M = 125 tonnes
v = 200 m/s
Force x 50 = 1/2 x 125,000 x (200)^2
Force = 50 x 10^6 Newtons or 50 MN
NIST NCSTAR 1-5D gives an estimated value for the force acting on WTC 2 from the aircraft impact as peaking at 75 MN. NIST show the force as declining uniformly to zero over a period of 0.6 seconds. Hence the average force would be 37.5 MN in reasonable agreement with the approximate calculation.
QUOTE (Daru+May 16 2008, 10:34 AM)
Suss suss..quiet !! Dont think about that.
But here are two men who did some calculation. But they dont tell the whole story. They dont have any floors in the test structure ! And more problem with theirs analysis.
"It was found that about 46% of the initial kinetic energy of the aircraft was used to damage columns. The minimum impact velocity of the aircraft to just penetrate the exterior columns would be 130 m/s. It was also found that a Boeing 767 traveling at top speed would not penetrate exterior columns of the WTC if the columns were thicker than 20 mm."Impact of the Boeing 767 Aircraft into the World Trade Center (click on the pdf)
But I can tell you that it is not possible for B767 to fully penitrate wtc totally intact ! and simply vanish inside the tower... and then suddenly explode ! I repeat: NOT possible. You would see some random damage, maybe the engines would penetrate (maybe) But what would not happen is what the videos of the impact shows. What will happen when a plane crash against massive steel and concrete structure like wtc is... a crash ! You will see the plane crash against the structure.
Actually it is more complex than simple calculations make it seem, your talking about aluminum oxide and the last time I checked that was 9 on the hardness scale.
I believe steel IS 6 on the same scale, also since some of the planes aluminum would ignite on dispersion in the oxygen in the air, it would be more like a hot knife though butter sheer event than a solid impact event and that has to be taken into consideration in any model of the event.
OH how boring this discussion has become, the same old topic and rants, very little new impute, it seems now mostly to be old reruns like a bad comedy sitcom before cancellation.
PS. NIST is wrong about the material in the rubble pile, carbon fuels would be used up, or cooled below ignition point if oxygen deprived, unless continually disturbed or reignited by an outside source.
35 days seems to be the limit for an insulated coal buried in soil or debris.
But here are two men who did some calculation. But they dont tell the whole story. They dont have any floors in the test structure ! And more problem with theirs analysis.
"It was found that about 46% of the initial kinetic energy of the aircraft was used to damage columns. The minimum impact velocity of the aircraft to just penetrate the exterior columns would be 130 m/s. It was also found that a Boeing 767 traveling at top speed would not penetrate exterior columns of the WTC if the columns were thicker than 20 mm."Impact of the Boeing 767 Aircraft into the World Trade Center (click on the pdf)
But I can tell you that it is not possible for B767 to fully penitrate wtc totally intact ! and simply vanish inside the tower... and then suddenly explode ! I repeat: NOT possible. You would see some random damage, maybe the engines would penetrate (maybe) But what would not happen is what the videos of the impact shows. What will happen when a plane crash against massive steel and concrete structure like wtc is... a crash ! You will see the plane crash against the structure.
Actually it is more complex than simple calculations make it seem, your talking about aluminum oxide and the last time I checked that was 9 on the hardness scale.
I believe steel IS 6 on the same scale, also since some of the planes aluminum would ignite on dispersion in the oxygen in the air, it would be more like a hot knife though butter sheer event than a solid impact event and that has to be taken into consideration in any model of the event.
OH how boring this discussion has become, the same old topic and rants, very little new impute, it seems now mostly to be old reruns like a bad comedy sitcom before cancellation.
PS. NIST is wrong about the material in the rubble pile, carbon fuels would be used up, or cooled below ignition point if oxygen deprived, unless continually disturbed or reignited by an outside source.
35 days seems to be the limit for an insulated coal buried in soil or debris.
the video of the collapse in denmark, or austria or wherever...
notice that when the collapse occurs, only the upper half of the building is burnt out.
after the collapse, they let it burn itself out(more that TWICE as much fuel, hence heat), and there was NO further collapse. not even any obvious deformation.
this fire supports the idea that steel buildings don't experience runaway GLOBAL collapse.
also notice that where the debris from the collapse landed(on top of the wider section underneath it), the building WAS NOT crushed, but held up to many stories in near freefall hitting it.
been busy.
love you all.
notice that when the collapse occurs, only the upper half of the building is burnt out.
after the collapse, they let it burn itself out(more that TWICE as much fuel, hence heat), and there was NO further collapse. not even any obvious deformation.
this fire supports the idea that steel buildings don't experience runaway GLOBAL collapse.
also notice that where the debris from the collapse landed(on top of the wider section underneath it), the building WAS NOT crushed, but held up to many stories in near freefall hitting it.
been busy.
love you all.
newton
Especially if they have concrete cores.
It must take real effort to keep posting such stupid crap all the time. No one could be that consistently wrong by chance. Even a stopped clock is right twice a day, but not our newton!!! His score is nearly a perfect 0.00
Grumpy
QUOTE
this fire supports the idea that steel buildings don't experience runaway GLOBAL collapse.
Especially if they have concrete cores.
It must take real effort to keep posting such stupid crap all the time. No one could be that consistently wrong by chance. Even a stopped clock is right twice a day, but not our newton!!! His score is nearly a perfect 0.00
Grumpy
This clearly shows how a totally global collapse of 3 massive steelstructures on 9/11 was outstanding abnormal.
It is better wiev here: www.youtube.com/watch?v=A4aKQXJtBdE
This is not a collapse. More like a very very small part brokes off.
I would like to know or see how this structure exactly was though.
It is better wiev here: www.youtube.com/watch?v=A4aKQXJtBdE
This is not a collapse. More like a very very small part brokes off.
I would like to know or see how this structure exactly was though.
QUOTE (Grumpy+May 25 2008, 01:45 AM)
newton
Especially if they have concrete cores.
It must take real effort to keep posting such stupid crap all the time. No one could be that consistently wrong by chance. Even a stopped clock is right twice a day, but not our newton!!! His score is nearly a perfect 0.00
Grumpy
leslie robertson said that concrete and steel were essentially weakened equally by fire. concrete through spalling, and steel through gradual loss of rigidity.
Especially if they have concrete cores.
It must take real effort to keep posting such stupid crap all the time. No one could be that consistently wrong by chance. Even a stopped clock is right twice a day, but not our newton!!! His score is nearly a perfect 0.00
Grumpy
leslie robertson said that concrete and steel were essentially weakened equally by fire. concrete through spalling, and steel through gradual loss of rigidity.
[sarcasm]But look at those pyroclastic flows, they're way to energetice, there has to be explosives, nukes, or alien death rays involved!!!!!![/sarcasm]
QUOTE (newton+May 27 2008, 06:28 PM)
leslie robertson said that concrete and steel were essentially weakened equally by fire. concrete through spalling, and steel through gradual loss of rigidity.
However steel reinforced concrete is not, spalling will occur in the concrete, releasing heat energy, that safe guards the steel inside allowing it to withstand longer duration fires at higher temperatures.
The concrete also acts as an insulator, when the concrete is spalled and cracked
to where the steel can be compromised, usually the fire has passed leaving the steel inside the concrete untouched.
It is not one of the other but the combination that works.
A car without gas will not get you very far, a car with plenty of gas can take you where ever the road goes.
Unfortunately CTers continue on a road to no where!
However steel reinforced concrete is not, spalling will occur in the concrete, releasing heat energy, that safe guards the steel inside allowing it to withstand longer duration fires at higher temperatures.
The concrete also acts as an insulator, when the concrete is spalled and cracked
to where the steel can be compromised, usually the fire has passed leaving the steel inside the concrete untouched.
It is not one of the other but the combination that works.
A car without gas will not get you very far, a car with plenty of gas can take you where ever the road goes.
Unfortunately CTers continue on a road to no where!
I posted the following at JREF http://forums.randi.org/showthread.php?t=103565 , to 'johnhutchinson' :
Are you "the" John Hutchinson? If so, please tell us what happened to samples sent to the Max Planck Institute. I sent them an email asking for a report, and didn't get an answer. For that matter, where is any scientific lab report on a sample?
Also, not that I know that "the Hutchinson Effect" explains this, but Kevin Ryan has recently reported coming into possession of hitherto unknown (by the public) photographs, regarding "roasted cars" in the the WTC parking garages. These were "nothing but metal"; "tires gone", "seats gone"; "headlights and taillights are gone"; "glass was not broken, but gone"; "covered with white dust which I would assume is fire suppressant"; "vaporized except for the metal".
Regarding fire suppressant, though, wouldn't a fire suppressant system be ruined before a car is done 'roasting'? Unless the system blew, the fires was not just hot but brief, and the fire suppressant chemicals were still suspended in the air when the 'roasting' was done.
He says he doesn't want to speculate as to the cause, but suggests a "very intense fire".
OTOH, he's not 100% sure of his source, so take with a grain of salt.
See the May 27 audio files at http://mp3.wtprn.com/Brouillet08.html , starting 48:57.
Are you "the" John Hutchinson? If so, please tell us what happened to samples sent to the Max Planck Institute. I sent them an email asking for a report, and didn't get an answer. For that matter, where is any scientific lab report on a sample?
Also, not that I know that "the Hutchinson Effect" explains this, but Kevin Ryan has recently reported coming into possession of hitherto unknown (by the public) photographs, regarding "roasted cars" in the the WTC parking garages. These were "nothing but metal"; "tires gone", "seats gone"; "headlights and taillights are gone"; "glass was not broken, but gone"; "covered with white dust which I would assume is fire suppressant"; "vaporized except for the metal".
Regarding fire suppressant, though, wouldn't a fire suppressant system be ruined before a car is done 'roasting'? Unless the system blew, the fires was not just hot but brief, and the fire suppressant chemicals were still suspended in the air when the 'roasting' was done.
He says he doesn't want to speculate as to the cause, but suggests a "very intense fire".
OTOH, he's not 100% sure of his source, so take with a grain of salt.
See the May 27 audio files at http://mp3.wtprn.com/Brouillet08.html , starting 48:57.
Graeme MacQueen seems to plot the acceleration of the north tower's antenna
http://911blogger.com/node/15793
I don't know which value he got but I think at this forum 0.66g is the measured value. Did anyone already have time to correct for the tilt, in other words if you have no hinge effect what would be the acceleration ?
http://911blogger.com/node/15793
I don't know which value he got but I think at this forum 0.66g is the measured value. Did anyone already have time to correct for the tilt, in other words if you have no hinge effect what would be the acceleration ?
Hi Einsteen!
If you take a look over at JREF on the conspiracy thread you will see there is already an on-going discussion of MacQueen's stuff. I give honorable mention to your smear-o-grams of the WTC collapse as the most detailed plots available. It would be very helpful if you could post one of the WTC 1 smear-o-grams over there as an example of how s-m-o-o-t-h the collapse was. I, and others, have tried to offer an explanation of this. Your thoughts would be most welcome!
If you take a look over at JREF on the conspiracy thread you will see there is already an on-going discussion of MacQueen's stuff. I give honorable mention to your smear-o-grams of the WTC collapse as the most detailed plots available. It would be very helpful if you could post one of the WTC 1 smear-o-grams over there as an example of how s-m-o-o-t-h the collapse was. I, and others, have tried to offer an explanation of this. Your thoughts would be most welcome!
Hi Neu,
In my last message at JREF I said that I will never post again and I will never do that...
Here is the post after which you determined the 0.3 seconds difference
http://www.physforum.com/index.php?showtop...80&#entry310749
I ffwd through his presentation, it doesn't look like something new. Yeah do you remember that we even compared the CDs smear-o-grams with the twin towers. They are always smooth because there is a big mass involved.
In my last message at JREF I said that I will never post again and I will never do that...
Here is the post after which you determined the 0.3 seconds difference
http://www.physforum.com/index.php?showtop...80&#entry310749
I ffwd through his presentation, it doesn't look like something new. Yeah do you remember that we even compared the CDs smear-o-grams with the twin towers. They are always smooth because there is a big mass involved.
Einsteen:
Sorry, I forgot about your committment never to post again at JREF. Can't say I blame you! You are indeed a man of your word and I admire and respect your integrity.
MacQueen is going over old ground and offering nothing new. Your smear-o-grams are the way to go and your original work on this should be recognized and published long before smoothy Mack Queen gets his say about anything. He is a NWO plagiarist at best, and certainly not interested in seeking out any scientific truths about 9/11.
I also agree that the apparent smoothness of the WTC 1 collapse is mainly due to the fact that the initial motion was tilting, not dropping.....
Sorry, I forgot about your committment never to post again at JREF. Can't say I blame you! You are indeed a man of your word and I admire and respect your integrity.
MacQueen is going over old ground and offering nothing new. Your smear-o-grams are the way to go and your original work on this should be recognized and published long before smoothy Mack Queen gets his say about anything. He is a NWO plagiarist at best, and certainly not interested in seeking out any scientific truths about 9/11.
I also agree that the apparent smoothness of the WTC 1 collapse is mainly due to the fact that the initial motion was tilting, not dropping.....
QUOTE (metamars+May 28 2008, 12:43 PM)
I posted the following at JREF http://forums.randi.org/showthread.php?t=103565 , to 'johnhutchinson' :
Are you "the" John Hutchinson? If so, please tell us what happened to samples sent to the Max Planck Institute. I sent them an email asking for a report, and didn't get an answer. For that matter, where is any scientific lab report on a sample?
Also, not that I know that "the Hutchinson Effect" explains this, but Kevin Ryan has recently reported coming into possession of hitherto unknown (by the public) photographs, regarding "roasted cars" in the the WTC parking garages. These were "nothing but metal"; "tires gone", "seats gone"; "headlights and taillights are gone"; "glass was not broken, but gone"; "covered with white dust which I would assume is fire suppressant"; "vaporized except for the metal".
Regarding fire suppressant, though, wouldn't a fire suppressant system be ruined before a car is done 'roasting'? Unless the system blew, the fires was not just hot but brief, and the fire suppressant chemicals were still suspended in the air when the 'roasting' was done.
He says he doesn't want to speculate as to the cause, but suggests a "very intense fire".
OTOH, he's not 100% sure of his source, so take with a grain of salt.
See the May 27 audio files at http://mp3.wtprn.com/Brouillet08.html , starting 48:57.
Or it is fire suppressant foam on a car fire, with chemical included in it after it drys.
PS. if the glass is gone there is no way to say if it was broken or not, it could have been sweep away in the pressure wave that followed the collapse and exposed all carbons to hot particulate materials, It also might have melted.
You can not say just by looking at a substance that it is fire suppressant material, you have to analyze it.
Are you "the" John Hutchinson? If so, please tell us what happened to samples sent to the Max Planck Institute. I sent them an email asking for a report, and didn't get an answer. For that matter, where is any scientific lab report on a sample?
Also, not that I know that "the Hutchinson Effect" explains this, but Kevin Ryan has recently reported coming into possession of hitherto unknown (by the public) photographs, regarding "roasted cars" in the the WTC parking garages. These were "nothing but metal"; "tires gone", "seats gone"; "headlights and taillights are gone"; "glass was not broken, but gone"; "covered with white dust which I would assume is fire suppressant"; "vaporized except for the metal".
Regarding fire suppressant, though, wouldn't a fire suppressant system be ruined before a car is done 'roasting'? Unless the system blew, the fires was not just hot but brief, and the fire suppressant chemicals were still suspended in the air when the 'roasting' was done.
He says he doesn't want to speculate as to the cause, but suggests a "very intense fire".
OTOH, he's not 100% sure of his source, so take with a grain of salt.
See the May 27 audio files at http://mp3.wtprn.com/Brouillet08.html , starting 48:57.
Or it is fire suppressant foam on a car fire, with chemical included in it after it drys.
PS. if the glass is gone there is no way to say if it was broken or not, it could have been sweep away in the pressure wave that followed the collapse and exposed all carbons to hot particulate materials, It also might have melted.
You can not say just by looking at a substance that it is fire suppressant material, you have to analyze it.
NEU-FONZE --- NWO?
New World Order!
I watched Dr. MacQueen in action at a truthers meeting here in Hamilton about 2 years ago. I am not convinced he is sincere at all .....
P.S. By the way, David, you should check out the diagrams of the collapse of WTC 1 posted by Gregory Urich on the JREF forum (on the MacQueen discussion thread).
Very interesting ..... and I am sure you would have a lot to say about it!
I watched Dr. MacQueen in action at a truthers meeting here in Hamilton about 2 years ago. I am not convinced he is sincere at all .....
P.S. By the way, David, you should check out the diagrams of the collapse of WTC 1 posted by Gregory Urich on the JREF forum (on the MacQueen discussion thread).
Very interesting ..... and I am sure you would have a lot to say about it!
You mean that you smell a rat...? like you said about Steven E. Jones.
Einsteen:
Throughout history, governments seeking to perpetuate injustice, yet being foresighted enough to channel and contain dissent against their corrupt, repressive policies, use groups of people called "The King’s Men". Such people get money, power, and benefits from "The King" but he denies knowing them since they pretend to oppose him. At the present time, when the term "trutherl" is bandied around, it is important to know who some of the alleged "truthers " really are, and to consider that some of the "9/11 Truth Movement" are "The King’s Men".
Recent American history has shown that many “revolutionaries” and counter-cultural “heroes” such as Abbie Hoffman, Jerry Rubin, Timothy Leary were in fact undercover government operatives.
Throughout history, governments seeking to perpetuate injustice, yet being foresighted enough to channel and contain dissent against their corrupt, repressive policies, use groups of people called "The King’s Men". Such people get money, power, and benefits from "The King" but he denies knowing them since they pretend to oppose him. At the present time, when the term "trutherl" is bandied around, it is important to know who some of the alleged "truthers " really are, and to consider that some of the "9/11 Truth Movement" are "The King’s Men".
Recent American history has shown that many “revolutionaries” and counter-cultural “heroes” such as Abbie Hoffman, Jerry Rubin, Timothy Leary were in fact undercover government operatives.
QUOTE (NEU-FONZE+May 29 2008, 01:20 PM)
Very interesting ..... and I am sure you would have a lot to say about it!
Could you grab them and post here?
I have considerably great technical/visual troubles using JREF.
Could you grab them and post here?
I have considerably great technical/visual troubles using JREF.
DBB,
I have tried to post Gregory Urich's diagrams of the WTC 1 collapse over here, apparently without success!
I have tried to post Gregory Urich's diagrams of the WTC 1 collapse over here, apparently without success!
QUOTE (einsteen+May 14 2008, 03:09 PM)
David S. Chandler uses a physics toolkit to calculate some ejections etc of the towers,
anyone seen it ?
http://www.youtube.com/watch?v=B9YjireIPCQ
He also uses the kit to measure wtc7's acceleration
http://www.youtube.com/watch?v=POUSJm--tgw
47 views only, the only thing he forgot is the camera angle, but that will
not change much at that position.
It seems to me that Mr. Chandler has made two rather simple errors in each of these analyses.
In the first video, he states that the horizontal ejection velocity (70 mph) was greater than the vertical velocity of the upper segment of the building (~35 mph) when the upper segment got to the original location of the ejected beam.
If I am interpreting him correctly, he is implying that this therefore requires some additional energy (bomb?) added to eject that segment.
Errors: First, he's got only one view angle. His calculation is therefore a MINIMUM horizontal velocity of the beam. To the extent that the beam's trajectory is actually towards or away from the observer by some angle Ø, then the actual horizontal velocity would be greater by a factor of (1/cosØ).
This appears to make his point even more strongly. But his second error is more glaring and negates this whole analysis.
The beams are NOT simple static structures that are knocked aside. There are two LARGE sources of stored energy in the beam that could easily give it this horizontal velocity without violating any physical laws.
First, the beam as it sits in the structure is under considerable compressive load. It is, in essence, a compressed spring. With a large amount of stored internal energy. Remove the end constraints suddenly, and this energy can easily contribute to a sizable horizontal shove.
The second source of error is much greater than this one. As a long slender compression member, the beam could (and most likely would) be flexed before snapping free at top & bottom. In this case, a BOATLOAD of internal energy would be stored in the flexing beam, and when the beam finally snaps free, could easily be tossed great distances.
Think of bending a paper clip between two fingers until it snaps free and flies across the room. Your fingers may have been moving together at 1 mph, but the paper clip flies at 10 mph. No physical principle violated.
By selecting the "most extreme" component of the dust cloud, Mr. Chandler has selected the most extreme outlier of several hundred (tragic) experiments in random disassembly of structures.
In his second analysis, his use of a HORIZONTAL calibration to measure VERTICAL speeds & accelerations is ill advised. This assumes a 1:1 aspect ratio. This assumption is usually incorrect for non-scientific imaging systems. He should repeat his experiment using a vertical calibration technique.
Second, if his image direction is not exactly perpendicular to the side of the building, then he will get another (1/cosØ) elongation in his scaling factor, suggesting higher speeds & accelerations that real.
(I will assume that he used several obvious techniques to improve his results, such as a smaller indicating dot and image zooming.)
When he does this, I would expect that he'd get an acceleration that is slightly below 9.8 m/sec. BTW, a calculation of the energy required to decrease the fall acceleration by some trivial amount (say 0.1 m/sec) would be very instructive to Mr. Chandler.
In his final conclusion that the "near free fall acceleration" of the building implies ... what?
It IS true that the failure of the cantilever truss section resulted in a global collapse of the building. It is true of this building, as it is of ALL buildings, that the dynamic loads generated by a moving structure FAR exceed the static carrying capacity of the structure. Ergo, all Controlled Demo buildings descend at "near free fall accelerations". And they all do so with their internal supports 99% intact. (They are blown only at a small segment near the base.)
And finally, in buildings assembled like all the towers, estimating the energy absorbing capacity of the structure by calculating the total energy absorbing capacity of the individual beams is a gross engineering error. It will overstate the energy absorption capacity by many orders of magnitude. As proven by the fact that the vast majority of the beams in the rubble were NOT torqued up pretzels. The failure mode is the snapping of 1" diameter bolts holding the vertical beams together & fracture of bolts and gusset welds of the cross trusses.
Once the cross trusses (alone) are removed, the beams will not be able to stand (i.e., support their own weight) without buckling, much less carry the weight of the building. It took little energy to snap these components on each floor.
It is no surprise in the slightest that a buildings like WTC 1, 2 & 7 came down at near free fall acceleration.
tk
anyone seen it ?
http://www.youtube.com/watch?v=B9YjireIPCQ
He also uses the kit to measure wtc7's acceleration
http://www.youtube.com/watch?v=POUSJm--tgw
47 views only, the only thing he forgot is the camera angle, but that will
not change much at that position.
It seems to me that Mr. Chandler has made two rather simple errors in each of these analyses.
In the first video, he states that the horizontal ejection velocity (70 mph) was greater than the vertical velocity of the upper segment of the building (~35 mph) when the upper segment got to the original location of the ejected beam.
If I am interpreting him correctly, he is implying that this therefore requires some additional energy (bomb?) added to eject that segment.
Errors: First, he's got only one view angle. His calculation is therefore a MINIMUM horizontal velocity of the beam. To the extent that the beam's trajectory is actually towards or away from the observer by some angle Ø, then the actual horizontal velocity would be greater by a factor of (1/cosØ).
This appears to make his point even more strongly. But his second error is more glaring and negates this whole analysis.
The beams are NOT simple static structures that are knocked aside. There are two LARGE sources of stored energy in the beam that could easily give it this horizontal velocity without violating any physical laws.
First, the beam as it sits in the structure is under considerable compressive load. It is, in essence, a compressed spring. With a large amount of stored internal energy. Remove the end constraints suddenly, and this energy can easily contribute to a sizable horizontal shove.
The second source of error is much greater than this one. As a long slender compression member, the beam could (and most likely would) be flexed before snapping free at top & bottom. In this case, a BOATLOAD of internal energy would be stored in the flexing beam, and when the beam finally snaps free, could easily be tossed great distances.
Think of bending a paper clip between two fingers until it snaps free and flies across the room. Your fingers may have been moving together at 1 mph, but the paper clip flies at 10 mph. No physical principle violated.
By selecting the "most extreme" component of the dust cloud, Mr. Chandler has selected the most extreme outlier of several hundred (tragic) experiments in random disassembly of structures.
In his second analysis, his use of a HORIZONTAL calibration to measure VERTICAL speeds & accelerations is ill advised. This assumes a 1:1 aspect ratio. This assumption is usually incorrect for non-scientific imaging systems. He should repeat his experiment using a vertical calibration technique.
Second, if his image direction is not exactly perpendicular to the side of the building, then he will get another (1/cosØ) elongation in his scaling factor, suggesting higher speeds & accelerations that real.
(I will assume that he used several obvious techniques to improve his results, such as a smaller indicating dot and image zooming.)
When he does this, I would expect that he'd get an acceleration that is slightly below 9.8 m/sec. BTW, a calculation of the energy required to decrease the fall acceleration by some trivial amount (say 0.1 m/sec) would be very instructive to Mr. Chandler.
In his final conclusion that the "near free fall acceleration" of the building implies ... what?
It IS true that the failure of the cantilever truss section resulted in a global collapse of the building. It is true of this building, as it is of ALL buildings, that the dynamic loads generated by a moving structure FAR exceed the static carrying capacity of the structure. Ergo, all Controlled Demo buildings descend at "near free fall accelerations". And they all do so with their internal supports 99% intact. (They are blown only at a small segment near the base.)
And finally, in buildings assembled like all the towers, estimating the energy absorbing capacity of the structure by calculating the total energy absorbing capacity of the individual beams is a gross engineering error. It will overstate the energy absorption capacity by many orders of magnitude. As proven by the fact that the vast majority of the beams in the rubble were NOT torqued up pretzels. The failure mode is the snapping of 1" diameter bolts holding the vertical beams together & fracture of bolts and gusset welds of the cross trusses.
Once the cross trusses (alone) are removed, the beams will not be able to stand (i.e., support their own weight) without buckling, much less carry the weight of the building. It took little energy to snap these components on each floor.
It is no surprise in the slightest that a buildings like WTC 1, 2 & 7 came down at near free fall acceleration.
tk
Obviously, both of the quote accelerations in the above post should have been "m/sec^2".
Typing too fast.
tk
Typing too fast.
tk
tomk --- Far slower acceleration than 'near free fall'. For the first few seconds of WTC 1, about (2/3)g.
QUOTE (NEU-FONZE+May 30 2008, 04:09 PM)
Einsteen:
Throughout history, governments seeking to perpetuate injustice, yet being foresighted enough to channel and contain dissent against their corrupt, repressive policies, use groups of people called "The King’s Men". Such people get money, power, and benefits from "The King" but he denies knowing them since they pretend to oppose him. At the present time, when the term "trutherl" is bandied around, it is important to know who some of the alleged "truthers " really are, and to consider that some of the "9/11 Truth Movement" are "The King’s Men".
Recent American history has shown that many “revolutionaries” and counter-cultural “heroes” such as Abbie Hoffman, Jerry Rubin, Timothy Leary were in fact undercover government operatives.
i'm impressed.
i've always considered YOU to be one of those 'king's men' with your gentle soft-soaping of conspiracy theory, LOL! perhaps, steven jones and some others, as well. it's good to keep a governor in every district.
who knows but the king, eh?
Throughout history, governments seeking to perpetuate injustice, yet being foresighted enough to channel and contain dissent against their corrupt, repressive policies, use groups of people called "The King’s Men". Such people get money, power, and benefits from "The King" but he denies knowing them since they pretend to oppose him. At the present time, when the term "trutherl" is bandied around, it is important to know who some of the alleged "truthers " really are, and to consider that some of the "9/11 Truth Movement" are "The King’s Men".
Recent American history has shown that many “revolutionaries” and counter-cultural “heroes” such as Abbie Hoffman, Jerry Rubin, Timothy Leary were in fact undercover government operatives.
i'm impressed.
i've always considered YOU to be one of those 'king's men' with your gentle soft-soaping of conspiracy theory, LOL! perhaps, steven jones and some others, as well. it's good to keep a governor in every district.
who knows but the king, eh?
QUOTE (David B. Benson+May 31 2008, 07:09 PM)
tomk --- Far slower acceleration than 'near free fall'. For the first few seconds of WTC 1, about (2/3)g.
David,
Not surprising at all.
The initial failure mode involved progressive creep and then buckling. While this is going on, the structural elements CAN provide a significant resistance to motion.
Also, initially, the upper segment is almost motionless and the dynamic overloads are small.
Once the upper segment had dropped it's initial 3 stories or so (remember, each vertical beam was about 3 stories high, so once one level is compromised, that is how far the upper segment will fall in response), then the failure mode changes to impact loading.
This loading simply blew apart each floor, requiring very little energy compared to what was available.
tk
David,
Not surprising at all.
The initial failure mode involved progressive creep and then buckling. While this is going on, the structural elements CAN provide a significant resistance to motion.
Also, initially, the upper segment is almost motionless and the dynamic overloads are small.
Once the upper segment had dropped it's initial 3 stories or so (remember, each vertical beam was about 3 stories high, so once one level is compromised, that is how far the upper segment will fall in response), then the failure mode changes to impact loading.
This loading simply blew apart each floor, requiring very little energy compared to what was available.
tk
tomk --- Not exactly like that, partly because of the tilting of the top section. Bazant & Verdure have an ASCE J. Engg. Mechanics paper describing the dynamical equation, called the crush-down equation. Now also Keith Seffen(sp?) has another in the same journal. Either agrees with the measurements taken (first few seconds only). Frank Greening wrote a paper on this earlier. It is hosted on the 911myths site. It also agrees with the measurements.
An appealing analogy appears to be vertical avalanche and it is possible that the collapse of WTC 1 reached terminal speed before the crushed mass reached the bottom basement floor.
An appealing analogy appears to be vertical avalanche and it is possible that the collapse of WTC 1 reached terminal speed before the crushed mass reached the bottom basement floor.
Against my better judgement ( ), I have started a thread at JREF, called NISTian black boxes - Oh, let me count the ways
I will copy the initial post here, but not subsequent ones:
The purpose of this thread is to cast light on what I'll call NISTian black boxes, as well as (what I believe) is the blindness of the NIST fan base regarding these black boxes. A NISTian black box is an insufficiently documented procedure, wherein a 'plan B' was pursued instead of an intial 'plan A', which affects the outcome of NIST's analysis in ways that can't be determined by the reader of the NIST docs. Indeed, I don't even think NIST knows - it's not just a question of documentation. Be that as it may, certainly the NIST apologists should be able to readily explain to us what's inside these black boxes, if their faith is of the scientific rather than religious type.
I should admit, from the beginning, that I haven't done my homework, in that the person to put the questions regarding the NISTian black boxes (NBB hereafter) should be somebody who understands the modeling technology. However, as nobody else has stepped forward to do this (including the now numerous engineering and architect professional members of ae911truth), I guess that I will plunge in where angels fear to tread! I have taken a graduate course in numerical methods, many years ago, but that in no way makes me suitable for the task at hand - even if I actually remembered most of what I had learned, which I don't.
The algorithm for producing the NBB's is pretty simple - load the NIST pdf file, search for the string "converge" (ignoring it in executive summaries), and record in this thread those instances where the plan B workaround for making the hitherto un-converging model converge. This will be followed by two question per incident, viz.,
Q1) what is the physical (as in "inherent physics captured in the software") difference in the two approaches, in general? The preferred form of this answer is in terms of list of various properties/behavior over a domain large enough to encompass the WTC scenario to which it is applied. I will guess that graphs are probably the best way to convey the information, though they'd ideally be accompanied by the equations from which they were derived.
Q2) what was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied? In particular, what was the quantitative effect of using the convergent method on the overall modeling behavior?
Some variation in this routine is expected, depending on the text, which I just happen to come across while using the "converge" string process. I don't recall NIST using the term "workaround", but it should be clear that I am talking about the computational method that was actually used, since the first method(s) contemplated either did not converge, or converged too slowly.
Now, 2) seems like a trick question, even to me. For if the first method, presumably involving the best guess of software widgets/algorithms/approximations that could be made by the NIST engineers, would not converge, how is answering 2) even possible? I don't know, but the answer may well be that it is never possible. OTOH, it may be possible to compute formulas for converging deltas between the two methods, some or all of the time.
It may turn out (I haven't looked at the NIST documents in a long time, I'm about to now) that even 1) is a trick question, of sorts. And the reason is that it may often be the case that even the convergent methods are not adequately documented. If the reader of NIST's 10,000 page report still cannot determine which elements of the toolbox were used at a given step in the modeling process (as well as whatever ancillary info was used), they sure as heck can't tell us what the deltas are with the (presumably) less documented non-converging methods.
I plan on only adding to this thread on weekends. This is not my life's work, even if this has proven to be a huge life diversion....
Also, I will not be going in order through the NCSTAR documents. I start with 5 examples in NCSTAR 1-6C.
OK, NIST apologists, this is your chance to really shine! Otherwise, some "twoofers" may come to the conclusion that proclaiming the NIST documents as an explanation was mostly an exercise of faith in NIST, rather than a fair (and of necessity, knowledgeable) evaluation of their work.
NBB #1: p. 12 / acrobat p.60
=======================
"To improve convergence in analysis, the negative slope in the stress-strain relationship after cracking or crushing in compression was removed, and the concrete was assumed to be plastic after cracking or crushing"
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #2: p. 73 / acrobat p.121
========================
"To improve convergence in analysis, the negative slope in the stress-strain relationship after cracking or crushing in compression was removed, and the concrete was assumed to be plastic after cracking or crushing"
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #3: p 77 / acrobat p. 125
===================
Gravity Plus Thermal Loading: The analysis of the truss model subjected to temperature time history was carried out statically; however, when the solution process did not converge, to overcome the convergence problem, the problem was solved dynamically with a 5 percent Rayleigh damping. The static analysis was then resumed when the acceleration and velocity became small.
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #4: p. 84 / Acrobat p. 132
=========================
Creep in shell was included in the simplified truss model; however, it was not included when the simplified truss model was incorporated in the full floor model, because of convergence problems inherent in BEAM188 elements.
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #5: p. 84 / Acrobat p. 132
========================
The concrete slab was modeled by SHELL181 elements with a temperature-dependent bilinear material model that had the same yield stength in both tension and compression. The yield strength was set to the compressive strength.
Q1) What is the physical difference between these two approaches, in general?
Comment Even a non-engineer like me knows that concrete does much better in compression than tension!
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
), I have started a thread at JREF, called NISTian black boxes - Oh, let me count the ways I will copy the initial post here, but not subsequent ones:
QUOTE
The purpose of this thread is to cast light on what I'll call NISTian black boxes, as well as (what I believe) is the blindness of the NIST fan base regarding these black boxes. A NISTian black box is an insufficiently documented procedure, wherein a 'plan B' was pursued instead of an intial 'plan A', which affects the outcome of NIST's analysis in ways that can't be determined by the reader of the NIST docs. Indeed, I don't even think NIST knows - it's not just a question of documentation. Be that as it may, certainly the NIST apologists should be able to readily explain to us what's inside these black boxes, if their faith is of the scientific rather than religious type.
I should admit, from the beginning, that I haven't done my homework, in that the person to put the questions regarding the NISTian black boxes (NBB hereafter) should be somebody who understands the modeling technology. However, as nobody else has stepped forward to do this (including the now numerous engineering and architect professional members of ae911truth), I guess that I will plunge in where angels fear to tread! I have taken a graduate course in numerical methods, many years ago, but that in no way makes me suitable for the task at hand - even if I actually remembered most of what I had learned, which I don't.
The algorithm for producing the NBB's is pretty simple - load the NIST pdf file, search for the string "converge" (ignoring it in executive summaries), and record in this thread those instances where the plan B workaround for making the hitherto un-converging model converge. This will be followed by two question per incident, viz.,
Q1) what is the physical (as in "inherent physics captured in the software") difference in the two approaches, in general? The preferred form of this answer is in terms of list of various properties/behavior over a domain large enough to encompass the WTC scenario to which it is applied. I will guess that graphs are probably the best way to convey the information, though they'd ideally be accompanied by the equations from which they were derived.
Q2) what was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied? In particular, what was the quantitative effect of using the convergent method on the overall modeling behavior?
Some variation in this routine is expected, depending on the text, which I just happen to come across while using the "converge" string process. I don't recall NIST using the term "workaround", but it should be clear that I am talking about the computational method that was actually used, since the first method(s) contemplated either did not converge, or converged too slowly.
Now, 2) seems like a trick question, even to me. For if the first method, presumably involving the best guess of software widgets/algorithms/approximations that could be made by the NIST engineers, would not converge, how is answering 2) even possible? I don't know, but the answer may well be that it is never possible. OTOH, it may be possible to compute formulas for converging deltas between the two methods, some or all of the time.
It may turn out (I haven't looked at the NIST documents in a long time, I'm about to now) that even 1) is a trick question, of sorts. And the reason is that it may often be the case that even the convergent methods are not adequately documented. If the reader of NIST's 10,000 page report still cannot determine which elements of the toolbox were used at a given step in the modeling process (as well as whatever ancillary info was used), they sure as heck can't tell us what the deltas are with the (presumably) less documented non-converging methods.
I plan on only adding to this thread on weekends. This is not my life's work, even if this has proven to be a huge life diversion....
Also, I will not be going in order through the NCSTAR documents. I start with 5 examples in NCSTAR 1-6C.
OK, NIST apologists, this is your chance to really shine! Otherwise, some "twoofers" may come to the conclusion that proclaiming the NIST documents as an explanation was mostly an exercise of faith in NIST, rather than a fair (and of necessity, knowledgeable) evaluation of their work.
NBB #1: p. 12 / acrobat p.60
=======================
"To improve convergence in analysis, the negative slope in the stress-strain relationship after cracking or crushing in compression was removed, and the concrete was assumed to be plastic after cracking or crushing"
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #2: p. 73 / acrobat p.121
========================
"To improve convergence in analysis, the negative slope in the stress-strain relationship after cracking or crushing in compression was removed, and the concrete was assumed to be plastic after cracking or crushing"
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #3: p 77 / acrobat p. 125
===================
Gravity Plus Thermal Loading: The analysis of the truss model subjected to temperature time history was carried out statically; however, when the solution process did not converge, to overcome the convergence problem, the problem was solved dynamically with a 5 percent Rayleigh damping. The static analysis was then resumed when the acceleration and velocity became small.
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #4: p. 84 / Acrobat p. 132
=========================
Creep in shell was included in the simplified truss model; however, it was not included when the simplified truss model was incorporated in the full floor model, because of convergence problems inherent in BEAM188 elements.
Q1) What is the physical difference between these two approaches, in general?
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
NBB #5: p. 84 / Acrobat p. 132
========================
The concrete slab was modeled by SHELL181 elements with a temperature-dependent bilinear material model that had the same yield stength in both tension and compression. The yield strength was set to the compressive strength.
Q1) What is the physical difference between these two approaches, in general?
Comment Even a non-engineer like me knows that concrete does much better in compression than tension!
Q2) What was the physical, quantitative difference which accrued by using the workaround in the specific WTC scenarios to which this workaround was applied?
QUOTE (NEU-FONZE+May 30 2008, 04:09 PM)
Throughout history...etc.
Statistically there will indeed be a few around I would say...
Statistically there will indeed be a few around I would say...
Quote--NEU-FONZE
"It would be very helpful if you could post one of the WTC 1 smear-o-grams over there as an example of how s-m-o-o-t-h the collapse was. I, and others, have tried to offer an explanation of this."
Quote--einsteen
"They (smear-o-grams) are always smooth because there is a big mass involved."
And yet, without any observable deceleration, especially at the beginning, we see this????
User posted image: User posted image
"It would be very helpful if you could post one of the WTC 1 smear-o-grams over there as an example of how s-m-o-o-t-h the collapse was. I, and others, have tried to offer an explanation of this."
Quote--einsteen
"They (smear-o-grams) are always smooth because there is a big mass involved."
And yet, without any observable deceleration, especially at the beginning, we see this????
User posted image: User posted image
Zoctoberfest:
A picture, is a picture, is a picture .......
I could show you a picture of the famous Hindenburg disaster of May, 1937.
Based on the picture alone, could you tell me what led to the destruction of that great zeppelin?
A picture, is a picture, is a picture .......
I could show you a picture of the famous Hindenburg disaster of May, 1937.
Based on the picture alone, could you tell me what led to the destruction of that great zeppelin?
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