Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1803068 times)

Offline deltaMass

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Inverted. Spot the difference

I can't.

Offline Dortex

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Inverted. Spot the difference

I can't.

These torsion tests are disappointing. Spinning articles and duplicate drives seem to be the best option for spotting thrust, artifact or otherwise.

Online Rodal

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Inverted. Spot the difference

I can't.

Looks like NULL results.  But we don't know whether the cavity was in resonance and what is the Q.

Why don't they use a Network Analyzer in transmission (S21) or reflection (S11) measurement to find out what is the quality factor of resonance (Q) of the Baby EM Drive under this excitation frequency instead of "flying blind" now for so many tests without knowing (or reporting) whether they are in resonance and what is the quality factor of resonance (Q) ?

There must be a Network Analyzer somewhere in Aachen...
« Last Edit: 06/20/2015 01:03 PM by Rodal »

Offline graybeardsyseng

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Future considerations:
Should the emdrive become a reality, I can envision a next-generation of high-power, miniaturized frustums (from my old filter days - when these were the newest disruptive innovation/technology introduced)

Speaking of disruptive technologies; this was from back in April, hard to tell if this was discussed or not as an option but:

http://www.nasa.gov/marshall/news/nasa-3-D-prints-first-full-scale-copper-rocket-engine-part.html

small frustum models should be easier and faster to 'print' than a whole engine part.

Hello - first time poster - long time reader - trying to refresh my 40 year ago physics and math heh heh. 

I have been looking into 3d printing with some of the new filament types (filled filament ceramics, conductives) with the intent of seeing if printing frustums for testing is starting to be both practical and affordable and where variations in geometry and operating point can be tested more easily.

Ceramics can be worked to desired smoothness and accuracy at the bisque stage and then fired, followed by deposition plating of desired material - all within some DIY capabilities.  Conductive filaments may not quite be there yet but we are getting close. 

  In terms of size, printing something like the Baby EMDrive wouldn't be hard but larger (Yang et al) would likely require printing in parts and assembling, with associated mechanical challenges.    I am particularly looking at how to do this and maintain the interior qualitative and quantitative requirements,  in particular as I want to do some experiments at lower frequencies - perhaps as low as ham radio 30cm band - spectrally pure rf sources with significant power are fairly common - although the frustum gets pretty big.


I think there is a real need for more data points (positive and/or negative results - they are all meaningful as long as experimental setup is well documented) in effects of frequency and geometry.   This seems to be to be an area where DIYers can add valuable data.

BTW - Has anyone looked at filtering the output of wideband sources (Magnetron) before injecting to the frustum?  Don't recall seeing in the thread(s) but I haven't read all yet.

EMdrive - finally - microwaves are good for something other than heating ramen noodles and leftover pizza ;-)

Online Rodal

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BTW - Has anyone looked at filtering the output of wideband sources (Magnetron) before injecting to the frustum?  Don't recall seeing in the thread(s) but I haven't read all yet.
Welcome to the thread.

Filtering wideband RF sources (Magnetron) may be counter-productive as:

1) The highest reported thrust/InputPower by far has been obtained by Prof. Yang in China using Magnetrons.  Her reported thrust/InputPower is much larger than Shawyer's and way more than NASA's.  NASA had the lowest thrust/InputPower and they did not use a Magnetron.

2) Due to induction heating from the magnetic field the EM Drive heats up, and therefore it expands due to thermal expansion.  Filtering the wideband source would be counterproductive, as it would be even more difficult to stay within resonance, particularly at high Q.

3) There are indications that the frequency, phase and amplitude modulation from the Magnetron may also be beneficial.  NASA was planning to conduct tests this summer to test this.

4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.
« Last Edit: 06/20/2015 03:18 PM by Rodal »

Offline rfmwguy

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Future considerations:
Should the emdrive become a reality, I can envision a next-generation of high-power, miniaturized frustums (from my old filter days - when these were the newest disruptive innovation/technology introduced)

Speaking of disruptive technologies; this was from back in April, hard to tell if this was discussed or not as an option but:

http://www.nasa.gov/marshall/news/nasa-3-D-prints-first-full-scale-copper-rocket-engine-part.html

small frustum models should be easier and faster to 'print' than a whole engine part.

Hello - first time poster - long time reader - trying to refresh my 40 year ago physics and math heh heh. 

I have been looking into 3d printing with some of the new filament types (filled filament ceramics, conductives) with the intent of seeing if printing frustums for testing is starting to be both practical and affordable and where variations in geometry and operating point can be tested more easily.

Ceramics can be worked to desired smoothness and accuracy at the bisque stage and then fired, followed by deposition plating of desired material - all within some DIY capabilities.  Conductive filaments may not quite be there yet but we are getting close. 

  In terms of size, printing something like the Baby EMDrive wouldn't be hard but larger (Yang et al) would likely require printing in parts and assembling, with associated mechanical challenges.    I am particularly looking at how to do this and maintain the interior qualitative and quantitative requirements,  in particular as I want to do some experiments at lower frequencies - perhaps as low as ham radio 30cm band - spectrally pure rf sources with significant power are fairly common - although the frustum gets pretty big.


I think there is a real need for more data points (positive and/or negative results - they are all meaningful as long as experimental setup is well documented) in effects of frequency and geometry.   This seems to be to be an area where DIYers can add valuable data.

BTW - Has anyone looked at filtering the output of wideband sources (Magnetron) before injecting to the frustum?  Don't recall seeing in the thread(s) but I haven't read all yet.

Hello...must say, your first post was light-years ahead of mine many pages ago ;). I'm putting together a DUT using Yang dimensions and copper mesh w/8W to try and obtain some lower Q, lower power data points. Think its about 1 month away.

Doc Rodal is right, the "spray" from the magnetron may indeed yield better results. I'm going CW for initial testing then may have to pulse mod it. I don't have a lab to back me up, so there are limits.

You sound like an RF guy, so one of the things of interest down the road is taking what is effectively an air cavity and reduce size with ceramic dielectric...just futurethought at this point.

I will have trouble measing Q at home without a network analyzer at my fingertips. I'll use the Q=F0/3db BW

Online Rodal

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...Hello...must say, your first post was light-years ahead of mine many pages ago ;). I'm putting together a DUT using Yang dimensions and copper mesh w/8W to try and obtain some lower Q, lower power data points. Think its about 1 month away...
A reminder to all that the only EM Drive researchers that have provided all dimensions of a tested truncated cone EM Drive have been Paul March at NASA, Iulian Berca and @Movax (Baby EM Drive).  Everybody else has failed to provide all required dimensions, hence the dimensions for Shawyer's and Yang's EM Drive's are best estimates based on their data.  Prof. Yang only provided the length of the truncated cone.  The other dimensions had to be estimated (interpolated) from her geometrical ratio charts and frequency.
« Last Edit: 06/20/2015 02:49 PM by Rodal »

Offline rfmwguy

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...Hello...must say, your first post was light-years ahead of mine many pages ago ;). I'm putting together a DUT using Yang dimensions and copper mesh w/8W to try and obtain some lower Q, lower power data points. Think its about 1 month away...
A reminder to all that the only EM Drive researchers that have provided all dimensions of a tested truncated cone EM Drive have been Paul March at NASA, Iulian Berca and @Movax (Baby EM Drive).  Everybody else has failed to provide all required dimensions, hence the dimensions for Shawyer's and Yang's EM Drive's are best estimates based on their data.  Prof. Yang only provided the length of the truncated cone.  The other dimensions had to be estimated (interpolated) from her geometrical ratio charts and frequency.

OK, you've got mine at 11.01 x 6.25 x 9.91"L as discussed with you and Traveller.

Online Rodal

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...OK, you've got mine at 11.01 x 6.25 x 9.91"L as discussed with you and Traveller.

OK, those dimensions are actually closer to NASA's and Iulian Berca's truncated cone geometry, and significantly different from Prof. Yang's dimensions (when taking into consideration the cone angle and the distance to the vertex of the cone).  The big and the small diameters are same as NASA's, the length is closest to Yang's.


(NASA has the following internal copper surface dimensions.Large OD : 11.00 " (0.2794m), Small OD: 6.25" (0.1588 m) & Length : 9.00 " (0.2286m) )




rfmwguy Dimensions

axial length = 0.252 meters = 9.91 inches
big diameter = 0.280 meters = 11.01 inches   [same as NASA]
small diameter = 0.159 meters =  6.25 inches  [same as NASA]

gives

r1= 0.340 meters

r2=0.599 meters

half cone angle = 13.5 degrees

See the dimensions of the other EM Drives here:  http://emdrive.wiki/Experimental_Results
« Last Edit: 06/20/2015 08:23 PM by Rodal »

Online WarpTech

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4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.

I'll tell you, I spent the past few days trying to find a solution using AC, GHz resonance. I've tried Maxwell's equations, Lorentz transformations, treating photons like massive particles per that paper I found the other day, and even a case where conservation of energy was blatantly violated. Every calculation results in 0-NET Momentum transfer to the frustum. I've done so much number crunching, my notebook is running low on paper!

I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

1. Remove the big end cover and it would thrust like an antenna.
2. Add losses that take away some of the energy reaching the big end, or let some leak out and then there will be thrust.
3. Add exponentially increasing or decreasing (DC) currents and allow DC fields to escape through the big end, then there will be thrust.

None of which result in thrust greater than a photon rocket, though if we have a 1000's of Amps DC stored when AC is at highest Q, then a photon rocket is in the ball park, just not continuously.
Todd



 

Online Rodal

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4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.

I'll tell you, I spent the past few days trying to find a solution using AC, GHz resonance. I've tried Maxwell's equations, Lorentz transformations, treating photons like massive particles per that paper I found the other day, and even a case where conservation of energy was blatantly violated. Every calculation results in 0-NET Momentum transfer to the frustum. I've done so much number crunching, my notebook is running low on paper!

I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

1. Remove the big end cover and it would thrust like an antenna.
2. Add losses that take away some of the energy reaching the big end, or let some leak out and then there will be thrust.
3. Add exponentially increasing or decreasing (DC) currents and allow DC fields to escape through the big end, then there will be thrust.

None of which result in thrust greater than a photon rocket, though if we have a 1000's of Amps DC stored when AC is at highest Q, then a photon rocket is in the ball park, just not continuously.
Todd
Mass/Energy needs to escape and amplification is needed as well.

The amplification factor reported over a photon rocket is

80 to 6,000 times for NASA's experiments
850 times for Iulian Berca's experiments


5,000 to 100,000 times for Shawyer's experiments
300,000 times for Prof.  Yang's experiments
« Last Edit: 06/20/2015 06:06 PM by Rodal »

Online RonM

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I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

While the details are interesting, there is nothing surprising about your final results. The forces cancelling out is what conventional wisdom expects.

I'm impressed by the mathematical skills and scientific knowledge shown by the people in this thread. Your research is way above my pay grade. Keep up the good work, but don't be surprised if you don't find anything. There are firm scientific reasons why many outright dismiss EM drives.

If these devices are producing thrust and the results are not experimental error, there must be new physics at work. Taught by experimentalists, I believe the data, but it has to be good and irrefutable data for a claim of this magnitude. Once we reach that state, then let the theorists sort it out.

Online Rodal

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4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.

I'll tell you, I spent the past few days trying to find a solution using AC, GHz resonance. I've tried Maxwell's equations, Lorentz transformations, treating photons like massive particles per that paper I found the other day, and even a case where conservation of energy was blatantly violated. Every calculation results in 0-NET Momentum transfer to the frustum. I've done so much number crunching, my notebook is running low on paper!

I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

1. Remove the big end cover and it would thrust like an antenna.
2. Add losses that take away some of the energy reaching the big end, or let some leak out and then there will be thrust.
3. Add exponentially increasing or decreasing (DC) currents and allow DC fields to escape through the big end, then there will be thrust.

None of which result in thrust greater than a photon rocket, though if we have a 1000's of Amps DC stored when AC is at highest Q, then a photon rocket is in the ball park, just not continuously.
Todd

What you find is useful in showing once again that neither Shawyer's or Yang's explanations make scientific sense (that a completely enclosed microwave cavity, without mass/energy escaping from it,  can outperform a perfectly collimated photon rocket by a factor of 10^5, and that, according to Shawyer, nothing outside Classical Physics is needed to explain it). 
« Last Edit: 06/20/2015 06:43 PM by Rodal »

Online SeeShells

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4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.

I'll tell you, I spent the past few days trying to find a solution using AC, GHz resonance. I've tried Maxwell's equations, Lorentz transformations, treating photons like massive particles per that paper I found the other day, and even a case where conservation of energy was blatantly violated. Every calculation results in 0-NET Momentum transfer to the frustum. I've done so much number crunching, my notebook is running low on paper!

I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

1. Remove the big end cover and it would thrust like an antenna.
2. Add losses that take away some of the energy reaching the big end, or let some leak out and then there will be thrust.
3. Add exponentially increasing or decreasing (DC) currents and allow DC fields to escape through the big end, then there will be thrust.

None of which result in thrust greater than a photon rocket, though if we have a 1000's of Amps DC stored when AC is at highest Q, then a photon rocket is in the ball park, just not continuously.
Todd
Mass/Energy needs to escape and amplification is needed as well.

The amplification factor reported over a photon rocket is

80 to 6,000 times for NASA's experiments
850 times for Iulian Berca's experiments


5,000 to 100,000 times for Shawyer's experiments
300,000 times for Prof.  Yang's experiments
When you hit a Frustum with a spewing magnetron @2.45Ghz radiating across the harmonics of four modes, TE011, TE012, TE111 and coupled with a heavy DC component popping on and off at 6ohz how can you calculate anything with that small slice of action in your calculations?   
Anyone take those three TE modes and digitally combine them into 1?

Shell

Offline dustinthewind

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https://hal.archives-ouvertes.fr/jpa-00246781/document
On the other hand, the 60 mm length of this region corresponds to a delay time of 0.2 nsec of light in vacuum, this is clearly longer than the measured delay in the first 5 nsec duration of the pulse superluminal conditions are present both for the center of gravity and the maximum value of the electromagnetic packet. Furthermore this confirmes the correctness of the frequency domain data and the corresponding Fourier evaluation [2, 3]. The zerc-time traversal described in references [2] and [3] proves to be correct, I-e- there is no additional time delay caused by an additional length of the evanescent region.
<end quote>

I know group velocities can appear greater than the speed of light but because the wave form information was previously propagated at light speed.  I suspect that may be what is happening and maybe this is what this paper is also suggesting. 

https://scholar.google.com/scholar?cluster=3707515693059191286&hl=en&as_sdt=5,48&sciodt=0,48

It is an interesting question. 

hmm on a second maybe they are implying that group velocity can't explain the results? "Finally, we discussed a pos-sible interpretation of the results, favoring the argument that the group velocity cannot be interpreted as a tunneling ve-locity."  Fascinating. 
« Last Edit: 06/20/2015 07:09 PM by dustinthewind »

Online Rodal

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4) Todd "WarpTech" has posted that magnetrons give a DC component that may be crucial to the EM Drive providing any significant thrust.

I'll tell you, I spent the past few days trying to find a solution using AC, GHz resonance. I've tried Maxwell's equations, Lorentz transformations, treating photons like massive particles per that paper I found the other day, and even a case where conservation of energy was blatantly violated. Every calculation results in 0-NET Momentum transfer to the frustum. I've done so much number crunching, my notebook is running low on paper!

I've even re-wrtitten SPR's Relativistic derivation correctly. The result was surprising, that regardless if waves are traveling forward or backward inside the frustum, the frustum always feels a push "forward" toward the small end. However, what reaches the big end ALWAYS cancels what was gained.  Attenuation (velocity), cone angle, Q, make no difference at all to these results.

1. Remove the big end cover and it would thrust like an antenna.
2. Add losses that take away some of the energy reaching the big end, or let some leak out and then there will be thrust.
3. Add exponentially increasing or decreasing (DC) currents and allow DC fields to escape through the big end, then there will be thrust.

None of which result in thrust greater than a photon rocket, though if we have a 1000's of Amps DC stored when AC is at highest Q, then a photon rocket is in the ball park, just not continuously.
Todd
Mass/Energy needs to escape and amplification is needed as well.

The amplification factor reported over a photon rocket is

80 to 6,000 times for NASA's experiments
850 times for Iulian Berca's experiments


5,000 to 100,000 times for Shawyer's experiments
300,000 times for Prof.  Yang's experiments
When you hit a Frustum with a spewing magnetron @2.45Ghz radiating across the harmonics of four modes, TE011, TE012, TE111 and coupled with a heavy DC component popping on and off at 6ohz how can you calculate anything with that small slice of action in your calculations?   
Anyone take those three TE modes and digitally combine them into 1?

Shell
The amplification could be due to a nonlinear effect that Todd has not taken into account.  Masers (and Lasers) involve amplification.  A solid state room-temperature Maser was invented during the last two decades but it is one meter long and it involves a special material to help amplification through emmission.

I have not calculated the combined effects of TE011, TE012 and TE111, and/or the effects of coupling with a DC component.

I can't calculate any thrust without mass/energy escaping the frustum somehow.  That's what bothers me the most.  I can't see how can the center of mass of an object be accelerated purely from the inside without expelling mass/energy to produce the thrust.
« Last Edit: 06/20/2015 07:07 PM by Rodal »

Online SeeShells

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https://hal.archives-ouvertes.fr/jpa-00246781/document
On the other hand, the 60 mm length of this region corresponds to a delay time of 0.2 nsec of light in vacuum, this is clearly longer than the measured delay in the first 5 nsec duration of the pulse superluminal conditions are present both for the center of gravity and the maximum value of the electromagnetic packet. Furthermore this confirmes the correctness of the frequency domain data and the corresponding Fourier evaluation [2, 3]. The zerc-time traversal described in references [2] and [3] proves to be correct, I-e- there is no additional time delay caused by an additional length of the evanescent region.
<end quote>

I know group velocities can appear greater than the speed of light but because the wave form information was previously propagated at light speed.  I suspect that may be what is happening and maybe this is what this paper is also suggesting. 

https://scholar.google.com/scholar?cluster=3707515693059191286&hl=en&as_sdt=5,48&sciodt=0,48

It is an interesting question.
It is a very interesting question. I've been mulling over this the last few days.
Shell

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I can't calculate any thrust without mass/energy escaping the frustum somehow.  That's what bothers me the most.  I can't see how can the center of mass of an object be accelerated purely from the inside without expelling mass/energy to produce the thrust.

Evanescent waves can escape using the DC component of the magnetron to "ride" on through the copper. We know they will appear upto a 1/3 wavelength from an antenna.

Also what has bothered me how can a evanescent wave that travels in a superluminal fashion even see normal vectors in matter and other waveforms? Where is the coupling mechanism that can effect a 2 vectored superluminal wave?

Whether these questions point you into another direction is unknown but these are the ones I'm puzzling over right now.   

Out to a steak cookout and a effervescent beverage. Have a good one all!!!

Shell

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Same guy who designed the EagleWorks Warp Ship...
Told me he was commissioned to do this work by same source that commissioned him to do the Warp Ship work.

My understanding is that the warp ship images were commissioned to illustrate a vision for FLT travel, in concert with a conference presentation by Dr. White on recent research. Note that the title of this image contains "Q-Thruster," a term used almost exclusively by White/March/EW to describe EMDrives and related experimental propulsion devices.

https://farm9.staticflickr.com/8851/17954163076_6d42a50f22_k.jpg

Perhaps EW is preparing to present their latest findings? Here's hoping!

Offline aero

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...OK, you've got mine at 11.01 x 6.25 x 9.91"L as discussed with you and Traveller.

OK, those dimensions are actually closer to NASA's and Iulian Berca's truncated cone geometry, and significantly different from Prof. Yang's dimensions (when taking into consideration the cone angle and the distance to the vertex of the cone).  The big and the small diameters are same as NASA's, the length is closest to Yang's.


(NASA has the following internal copper surface dimensions.Large OD : 11.00 " (0.2794m), Small OD: 6.25" (0.1588 m) & Length : 9.00 " (0.2286m) )




rfmwguy Dimensions

axial length = 0.251714 meters = 9.91 inches
big diameter = 0.279654 meters = 11.01 inches   [same as NASA]
small diameter = 0.15875 meters =  6.25 inches  [same as NASA]

gives

r1= 0.339905 meters

r2=0.598776 meters

half cone angle = 13.5045 degrees

See the dimensions of the other EM Drives here:  http://emdrive.wiki/Experimental_Results
Re. NASA dimensions. I am confused. You state that the measurements are internal dimensions then in the same breath say that they are OD. OD normally stands for Outer Diameter. I know that the dielectric disks used are 6.25 inches, OD, which makes the small diameter of the cavity >= 6.25 inches, ID. The others, I'm not sure as I'm not sure where you are coming up with the numbers, but I think it is the origonal Brady cavity. The dimensions of the NASA copper kettle cavity are a little different, given in the attached, as provided by Paul March.
Retired, working interesting problems

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