I've had the good fortune to be cited at Swans on Tea and to be included in the blog roll at Dot Physics. This has been gratifying, we all want to be heard when we step onto our soapbox. However, it's caused me to wonder what's really going on when we blog.
Naturally, I've gone to other blogs on the blog rolls of each of those sites, and on to others from those. This is what "web surfing" was about back when I first got involved with the internet in 1995 (holy crap, by the way). Several times, through circuitous routes, I wound up coming to various blogs from different directions. Thus, one might speculate that I would find myself in general agreement with the editorial viewpoint of such blogs. After all, I got there, in a sense, from my own. Is this true and does it matter?
The answers are "not necessarily" and "I think so." For example, I wound up on a site called Pharyngula, published by a biologist named PZ Myers. It is a stridently atheistic site. Now, at various times in my life I've been militantly atheistic, I've been a Christian believer, and I've been agnostic. I'm currently in "searching" mode and find much of value in the essays of Professor Steven Dutch's "Science, Pseudoscience, and Irrationalism" pages. Dr. Dutch, a professor in the Earth Sciences department at the University of Wisconsin Green Bay, is relentlessly rational and no one that I've read does a better job of demolishing all manner of pseudoscience. And yet, he is a person of faith.
The Pharyngula blog is one of many at a site called ScienceBlogs. Another is the Denialism Blog which discusses a variety of pseudoscientific and crank ideas. Typical targets are Intelligent Design proponents, global warming denialists, Holocaust denialists, 9/11 conspiracy theorists, etc. Sometimes they may point out the logical fallacies present in the arguments of the denialists, other times they may delve into their psychology. I find myself generally aligned with the viewpoints presented. But not always and not completely.
After a comment I added to a post in Pharyngula I found myself characterized as an idiot, an absolute lunatic, a troll, a slimy troll, and a dipshit (though the person who called me the last weakly retracted it), and was told to "fuck off." Then, not surprisingly, when I did so I was accused of "stomping off in a huff." What was my offense? Well, the post topic was a video featuring Bill Donohue being quite belligerent toward a victim of sexual abuse by the Catholic clergy.
Now, I found Donohue's behavior reprehensible and never said otherwise. But I did feel, reading the comments, an air of smug superiority in the commenters with the flavor of "this kind of thing would never happen but for the unenlightened, superstitious, theistic thinking of the Catholic Church." I concede that I chose a confrontational way of making this point, to wit, I wrote:
"The context of this post and of the video is implying something to the effect that 'theistic thinking increases the likelihood of sexual and physical abuse of minors.'
So, then, may I assume, based on Stalin's Soviet Union, that 'atheistic thinking increases the likelihood of mass murder?'"
My point was that evil is evil and those who engage in it will use whatever is their (or the prevailing) ideology to justify such behavior, should such justification be necessary.
I would not have chosen such an incendiary entry into the discussion but the air of self-righteous chest thumping (interspersed with various suggestions of physical abuse and torture to be inflicted upon Mr. Donohue, quoting one of Myers' favorite phrases, "I kid you not") of some (not all) of the participants was quite off-putting. And yet, I undoubtedly have much in common with many of the contributors. The blogosphere, like politics, makes strange bedfellows.
A look at energy use in my life and how it applies to others' lives
“Be kind, for everyone you meet is fighting a hard battle” - Often attributed to Plato but likely from Ian McLaren (pseudonym of Reverend John Watson)
Wednesday, June 10, 2009
Saturday, June 06, 2009
The amazing 110 m.p.g. Mustang
Doug Pelmear of HP2g and something called HorsepowerSales.net has made a lot of claims for his engine development. He claims to have developed a "rod and piston" engine capable of developing 400 horsepower and 500 foot pounds of torque. It's also, per Pelmear, capable of 110 m.p.g. equivalent. It's "equivalent" because the engine uses E85 fuel, 85% ethanol and 15% gasoline.
Pelmear had touted his entry into the Progressive Automotive X Prize competition, whose organizers will distribute a $10M prize pool for teams that produce commercially viable vehicles capable of achieving a sustained fuel economy of 100 MPGe (m.p.g. equivalent). Pelmear's HP2g entry was to have been a 1987 Mustang with his proprietary engine installed. However, a press release dated June 4, 2009 states that the HP2g Mustang has been withdrawn from the competition despite several videos (see here and here for example) showing Pelmear expressing his confidence that he'd win the prize. Various reasons are given for the withdrawal, I have no data regarding the legitimacy of the rationale, so I'll just take it at face value.
There are several articles on the HP2g web site announcing the opening, on June 1, 2009 of an engine R & D and manufacturing plant. There's also news of an agreement between HP2g and "Revenge Designs" to install the engines in the "Revenge Verde," a super car of some sort. I can't find a lot of detail about the Revenge Verde, but a rendering is at left.
Little information about the actual technology being employed is available on HP2g's web site or in any of the recorded interviews at the various media events Pelmear has attended. He's referred to technology originated during World War 2 by his grandfather and to extensive electronics. There are a couple of vague references to "more precise manufacturing techniques" and "tighter tolerances." In all the videos, the hood of the car is closed and in most the Mustang is sitting still. In the ones where it's moving, it's driving in a very normal fashion, no 400 h.p. tire smoking burnouts. Though his site has a "table of fill ups and miles driven", no independent authentication is given or even implied.
Skepticism is rampant on the Ecomodder Blog about the Mustang, as might be inferred from the title of the article ("runs on hot air and cattle manure" for those not wanting to click on or mouse over the link). I actually commented there and didn't find it to be utterly, completely, totally impossible for Pelmear's claims to be true. But his site includes a section entitled "Test Data" that should enable me to get a more precise estimate as to the plausibility of his claims.
The relevant data is as follows (and compliments to Pelmear and HP2g for publishing them, though the pertinent ones are really just stock Mustang numbers):
Pelmear had touted his entry into the Progressive Automotive X Prize competition, whose organizers will distribute a $10M prize pool for teams that produce commercially viable vehicles capable of achieving a sustained fuel economy of 100 MPGe (m.p.g. equivalent). Pelmear's HP2g entry was to have been a 1987 Mustang with his proprietary engine installed. However, a press release dated June 4, 2009 states that the HP2g Mustang has been withdrawn from the competition despite several videos (see here and here for example) showing Pelmear expressing his confidence that he'd win the prize. Various reasons are given for the withdrawal, I have no data regarding the legitimacy of the rationale, so I'll just take it at face value.
There are several articles on the HP2g web site announcing the opening, on June 1, 2009 of an engine R & D and manufacturing plant. There's also news of an agreement between HP2g and "Revenge Designs" to install the engines in the "Revenge Verde," a super car of some sort. I can't find a lot of detail about the Revenge Verde, but a rendering is at left.
Little information about the actual technology being employed is available on HP2g's web site or in any of the recorded interviews at the various media events Pelmear has attended. He's referred to technology originated during World War 2 by his grandfather and to extensive electronics. There are a couple of vague references to "more precise manufacturing techniques" and "tighter tolerances." In all the videos, the hood of the car is closed and in most the Mustang is sitting still. In the ones where it's moving, it's driving in a very normal fashion, no 400 h.p. tire smoking burnouts. Though his site has a "table of fill ups and miles driven", no independent authentication is given or even implied.
Skepticism is rampant on the Ecomodder Blog about the Mustang, as might be inferred from the title of the article ("runs on hot air and cattle manure" for those not wanting to click on or mouse over the link). I actually commented there and didn't find it to be utterly, completely, totally impossible for Pelmear's claims to be true. But his site includes a section entitled "Test Data" that should enable me to get a more precise estimate as to the plausibility of his claims.
The relevant data is as follows (and compliments to Pelmear and HP2g for publishing them, though the pertinent ones are really just stock Mustang numbers):
- Cd (Coefficient of Drag): 0.42
- Frontal Area: 22 ft^2 (2.044 m^2)
- Curb weight: 3250 pounds (curb mass of 1474 kg)
We'll add the following: two 75 kilogram passengers; tires with coefficient of rolling resistance of 0.010 (this is relatively low, but what the heck).
So what does that mean at 55 m.p.h., or 24.59 m/s? Ignoring the energy in the rotating masses and using the methodology I've illustrated many times in the course of this blog, I'd estimate that about 470 newtons would propel this Mustang down the highway at a steady speed on level ground with no wind. As I've frequently mentioned, force times speed is power (assuming that the force is directed parallel to the velocity so that vector calculations aren't required) so 470 newtons at 24.59 m/s requires 11.56 kilowatts or 15.51 horsepower.
Moving on, E85 fuel should have a heat of combustion (that is, energy converted through burning) of 8.653*10^7 j/gal (joules/gallon). I will assume "110 MPGe" means that if E85 had the same specific energy (energy per unit volume) as gasoline, the vehicle would travel 110 miles on a gallon of it. So I'll multiply 110 miles by the ratio of the energy content of E85 to that of gasoline, or 8.653*10^7/1.225*10^8 and speculate that Pelmear is claiming about 77.7 miles out of a gallon of E85. Equivalently, Pelmear would be burning 1/77.7 or 0.01287 gallons of E85 per mile. In that fraction of a gallon, there are 1.1136*10^6 joules of thermal energy available through combustion.
We'll ignore the fuel needed to add the kinetic energy required to get the vehicle to 55 m.p.h. and the various rotating masses in motion and just look at the energy required to maintain 55 m.p.h. with conditions as detailed above. A mile is 1609 meters, so exerting a force of 470 newtons over that distance requires doing work of 756,700 joules. These joules come from burning the E85 so Pelmear is claiming an efficiency of at least (remember we ignored adding kinetic energy, hills, wind, etc.) of 7.567*10^5/1.1136*10^6 or 68%.
This would be above the maximum theoretical thermodynamic efficiency possible with an Otto cycle engine. Even granting that E85 has a significantly higher octane rating than any straight gasoline and thus allows much higher compression ratios to be used and assuming Pelmear has increased his compression ratio to 15:1 (which would require much more massive components than those in a stock gasoline engine), the maximum theoretical efficiency would be about 66%. This assumes no friction in the engine, no throttling or pumping losses, no energy to accessories, etc.
Note that I've given Pelmear the benefit of the doubt at every turn. The most generous assumption I've made is to run the calculations at 55 m.p.h. His site references speeds of 70 m.p.h. where much more energy would be required. And any variance from the idealized conditions hypothesized would reduce the fuel efficiency. I'm sorry, but unless someone points out an error in my calculations or data, I'm calling shenanigans.
Update: I've looked at more of the figures from HP2g's site for fill ups and mileage. They are showing numbers as high as 136.85 m.p.g. (actual miles divided by actual U.S. gallons, MPGe would be much higher). This would mean that the HP2g Mustang was getting significantly more than 100% of the energy available in the E85.
Update 2: A series of email correspondences with HP2g is shown below. Make of them what you will (start at the bottom and work up). Note that the engine "does not necessarily defy the laws of physics" (italics mine).
Update 3: Progressive Insurance Automotive X PRIZE Responds to HP2g Claims
Update 4: In this video the interviewer (from CNN) states that developers think that with a little more tweaking they'll get 500 miles per gallon.
Edison had naysayers too, I'm glad he continued on... Please refrain from contacting us again. First/Last warning.
-----Original Message----- From: Rob
Sent: Monday, June 8, 2009 02:34 PM
To:
Subject: RE: Your claims
Good morning,
No technologies enable more energy to be derived from fuel than is available in the fuel to begin with. Certainly there are thermodynamic cycles other than the Otto cycle, but none of them allow the conversion of more chemical energy to kinetic energy and work than are available in the chemical energy to begin with. Mileage figures such as 136.85 m.p.g. with the drag area of a Mustang and the rolling resistance of any tires currently available would exceed that amount by a considerable margin. There are a variety of reasons why such a claim would be made, but getting more energy out than is in the fuel is not one of them. Pending further information, it's very difficult for me to find such claims plausible. If you can supply such information, fine. If not, I guess time will tell.
Thanks,
Rob
From:
Sent: Monday, June 08, 2009 11:00 AM
To: Rob
Subject: Re: Your claims
Hello, Rob: The HP2g not only has been EPA tested, but its fuel economy has been ested in over 8,000 miles of driving in cities, towns, interstates, desserts, mountains and speed tests. The HP2g’s technologies are not those that you know and are familiar with. The engine does not necessarily defy the laws of physics just our prior understanding of how engines are supposed to work. When we are authorized to release the EPA info we will. It is in our possession. Thank you,
Team HP2g
-----Original Message----- From: Rob
Sent: Monday, June 8, 2009 12:17 AM
To:
Subject: RE: Your claims
Can you provide documentation? It’s very difficult to defy the laws of physics.
Rob
From:
Sent: Sunday, June 07, 2009 9:11 PM
To: Rob
Subject: Re: Your claims
EPA tested.
-----Original Message----- From: Rob
Sent: Sunday, June 7, 2009 10:36 PM
To:
Subject: Your claims
I’m afraid that very straightforward calculations show that your claims, as stated, cannot be correct. I wish that they were.
The calculations are at http://hamiltonianfunction.blogspot.com/2009/06/amazing-110-mpg-mustang_06.html.
If there are errors there, I’m sure you’ll point them out.
Rob
So what does that mean at 55 m.p.h., or 24.59 m/s? Ignoring the energy in the rotating masses and using the methodology I've illustrated many times in the course of this blog, I'd estimate that about 470 newtons would propel this Mustang down the highway at a steady speed on level ground with no wind. As I've frequently mentioned, force times speed is power (assuming that the force is directed parallel to the velocity so that vector calculations aren't required) so 470 newtons at 24.59 m/s requires 11.56 kilowatts or 15.51 horsepower.
Moving on, E85 fuel should have a heat of combustion (that is, energy converted through burning) of 8.653*10^7 j/gal (joules/gallon). I will assume "110 MPGe" means that if E85 had the same specific energy (energy per unit volume) as gasoline, the vehicle would travel 110 miles on a gallon of it. So I'll multiply 110 miles by the ratio of the energy content of E85 to that of gasoline, or 8.653*10^7/1.225*10^8 and speculate that Pelmear is claiming about 77.7 miles out of a gallon of E85. Equivalently, Pelmear would be burning 1/77.7 or 0.01287 gallons of E85 per mile. In that fraction of a gallon, there are 1.1136*10^6 joules of thermal energy available through combustion.
We'll ignore the fuel needed to add the kinetic energy required to get the vehicle to 55 m.p.h. and the various rotating masses in motion and just look at the energy required to maintain 55 m.p.h. with conditions as detailed above. A mile is 1609 meters, so exerting a force of 470 newtons over that distance requires doing work of 756,700 joules. These joules come from burning the E85 so Pelmear is claiming an efficiency of at least (remember we ignored adding kinetic energy, hills, wind, etc.) of 7.567*10^5/1.1136*10^6 or 68%.
This would be above the maximum theoretical thermodynamic efficiency possible with an Otto cycle engine. Even granting that E85 has a significantly higher octane rating than any straight gasoline and thus allows much higher compression ratios to be used and assuming Pelmear has increased his compression ratio to 15:1 (which would require much more massive components than those in a stock gasoline engine), the maximum theoretical efficiency would be about 66%. This assumes no friction in the engine, no throttling or pumping losses, no energy to accessories, etc.
Note that I've given Pelmear the benefit of the doubt at every turn. The most generous assumption I've made is to run the calculations at 55 m.p.h. His site references speeds of 70 m.p.h. where much more energy would be required. And any variance from the idealized conditions hypothesized would reduce the fuel efficiency. I'm sorry, but unless someone points out an error in my calculations or data, I'm calling shenanigans.
Update: I've looked at more of the figures from HP2g's site for fill ups and mileage. They are showing numbers as high as 136.85 m.p.g. (actual miles divided by actual U.S. gallons, MPGe would be much higher). This would mean that the HP2g Mustang was getting significantly more than 100% of the energy available in the E85.
Update 2: A series of email correspondences with HP2g is shown below. Make of them what you will (start at the bottom and work up). Note that the engine "does not necessarily defy the laws of physics" (italics mine).
Update 3: Progressive Insurance Automotive X PRIZE Responds to HP2g Claims
Update 4: In this video the interviewer (from CNN) states that developers think that with a little more tweaking they'll get 500 miles per gallon.
Edison had naysayers too, I'm glad he continued on... Please refrain from contacting us again. First/Last warning.
-----Original Message----- From: Rob
Sent: Monday, June 8, 2009 02:34 PM
To:
Subject: RE: Your claims
Good morning,
No technologies enable more energy to be derived from fuel than is available in the fuel to begin with. Certainly there are thermodynamic cycles other than the Otto cycle, but none of them allow the conversion of more chemical energy to kinetic energy and work than are available in the chemical energy to begin with. Mileage figures such as 136.85 m.p.g. with the drag area of a Mustang and the rolling resistance of any tires currently available would exceed that amount by a considerable margin. There are a variety of reasons why such a claim would be made, but getting more energy out than is in the fuel is not one of them. Pending further information, it's very difficult for me to find such claims plausible. If you can supply such information, fine. If not, I guess time will tell.
Thanks,
Rob
From:
Sent: Monday, June 08, 2009 11:00 AM
To: Rob
Subject: Re: Your claims
Hello, Rob: The HP2g not only has been EPA tested, but its fuel economy has been ested in over 8,000 miles of driving in cities, towns, interstates, desserts, mountains and speed tests. The HP2g’s technologies are not those that you know and are familiar with. The engine does not necessarily defy the laws of physics just our prior understanding of how engines are supposed to work. When we are authorized to release the EPA info we will. It is in our possession. Thank you,
Team HP2g
-----Original Message----- From: Rob
Sent: Monday, June 8, 2009 12:17 AM
To:
Subject: RE: Your claims
Can you provide documentation? It’s very difficult to defy the laws of physics.
Rob
From:
Sent: Sunday, June 07, 2009 9:11 PM
To: Rob
Subject: Re: Your claims
EPA tested.
-----Original Message----- From: Rob
Sent: Sunday, June 7, 2009 10:36 PM
To:
Subject: Your claims
I’m afraid that very straightforward calculations show that your claims, as stated, cannot be correct. I wish that they were.
The calculations are at http://hamiltonianfunction.blogspot.com/2009/06/amazing-110-mpg-mustang_06.html.
If there are errors there, I’m sure you’ll point them out.
Rob
Friday, June 05, 2009
A cornucopia of cluelessness
Not satisfied with the gems I located for A potpourri of cluelessness, my research has revealed more examples of complete misunderstanding of the nature of the physical world. If there's "illiteracy," and "innumeracy" then there should be "ill-physics-acy."
For the first, a hat tip to my friend Michael, the publisher of Only In It For The Gold. He posted this gem. The discussion related to the Zap-X electric car by ZAP, a California Corporation specializing in all types of electric vehicles. I've posted about their Zapino, a small electric scooter.
In any case, the post linked by Michael was to an Ecogeek discussion of the Zap-X, which is apparently a moribund concept. But in the comments, "free energy now" replied to a very rational demolition of the claims for the Zap-X with the following:
"Bruce Your comments in compairing the car to cold fusion means that you're assuming that technology can't change the 746w/hp. Is it at all possible that the cars engines are more efficient then your calculations allow for. There are also ways of using capacitors to increase efficiency in heavy load conditions. Technology is changing my friend, and in a lot of situations the nubers just don't add up. My friend has designed a heater which can run indefinitly after a couple of days of being pluged in. He heats his whole house with them, no they don't use cold fusion, just an ingenious design. So just because you can't figure out the math, doesn't mean it's immposible. Peace out"
Amazing. We're going to change a unit conversion factor using technology. Apparently, such a breakthrough will also enable us to develop overunity devices, overcome the Second Law of Thermodynamics, and achieve perpetual motion. I suggested in my comment on Michael's blog that perhaps we should also be looking into the technological possibility of getting more gallons per liter and more miles per kilometer. In fact, why stop there? I will look into employing technology to change the number of centimeters per inch and make myself taller and lengthen my.... But I digress.
Further, as has been pointed out in the comments to the "In It" post, turning electricity to heat is close to 100% efficient, so it's hardly likely to see dramatic improvements.
Moving on, a "Guest" on the CR4 forum replied to a thread entitled "Overall efficiency of gasoline powered cars" with the following:
"Here is a sample calculation of this... change as you need.. Assume the car travels 1 mile at 30m/sec on a flat road(highway speed... 60mph=88ft/sec about 30m/s) and that it gets 36.7 mpg (conveniently chosen to cancel with your 36.7 kw hour/gal). assume the car is 1000 kg. So energy in for 1 mile is 0.5m*v^2 = 450,000Joules Energy put in for 1 mile in terms of gas is 1gal/36.7miles * 36.7kWhr/gal =1kwhr or 1kJoules/sec*3600Sec = 3.6x10^6 joules... so overall efficiency is 0.45/3.6 = 12.5% for this example... change the parameters to get other results... i.e. mass of car, mpg, average speed etc.. adonaldson@calbaptist.edu engineering prof"
The questioner replied to this answer with "Thanks. That's what I was looking for." It's too bad that he or she found it because it's completely wrong. The "engineering prof" calculated the kinetic energy of the moving vehicle and then somehow decided that that's the energy required to move the vehicle one mile. Of course, the kinetic energy of a given vehicle depends only on its speed and has nothing to do with how far the vehicle travels at that speed. To start from a standstill and accelerate to speed requires turning chemical potential energy into kinetic energy, but so does overcoming aerodynamic drag, rolling resistance, etc., not to mention the kinetic energy of the various rotating masses (flywheel, tires, etc.). All of this was ignored.
If this is truly an engineering prof., I grieve for our future. Of course, even if it isn't I'm not all that sanguine. Anyway, I'm sure I'll find plenty of material for my semi-regular session of poking fun at the published factual ignorance on the 'net.
For the first, a hat tip to my friend Michael, the publisher of Only In It For The Gold. He posted this gem. The discussion related to the Zap-X electric car by ZAP, a California Corporation specializing in all types of electric vehicles. I've posted about their Zapino, a small electric scooter.
In any case, the post linked by Michael was to an Ecogeek discussion of the Zap-X, which is apparently a moribund concept. But in the comments, "free energy now" replied to a very rational demolition of the claims for the Zap-X with the following:
"Bruce Your comments in compairing the car to cold fusion means that you're assuming that technology can't change the 746w/hp. Is it at all possible that the cars engines are more efficient then your calculations allow for. There are also ways of using capacitors to increase efficiency in heavy load conditions. Technology is changing my friend, and in a lot of situations the nubers just don't add up. My friend has designed a heater which can run indefinitly after a couple of days of being pluged in. He heats his whole house with them, no they don't use cold fusion, just an ingenious design. So just because you can't figure out the math, doesn't mean it's immposible. Peace out"
Amazing. We're going to change a unit conversion factor using technology. Apparently, such a breakthrough will also enable us to develop overunity devices, overcome the Second Law of Thermodynamics, and achieve perpetual motion. I suggested in my comment on Michael's blog that perhaps we should also be looking into the technological possibility of getting more gallons per liter and more miles per kilometer. In fact, why stop there? I will look into employing technology to change the number of centimeters per inch and make myself taller and lengthen my.... But I digress.
Further, as has been pointed out in the comments to the "In It" post, turning electricity to heat is close to 100% efficient, so it's hardly likely to see dramatic improvements.
Moving on, a "Guest" on the CR4 forum replied to a thread entitled "Overall efficiency of gasoline powered cars" with the following:
"Here is a sample calculation of this... change as you need.. Assume the car travels 1 mile at 30m/sec on a flat road(highway speed... 60mph=88ft/sec about 30m/s) and that it gets 36.7 mpg (conveniently chosen to cancel with your 36.7 kw hour/gal). assume the car is 1000 kg. So energy in for 1 mile is 0.5m*v^2 = 450,000Joules Energy put in for 1 mile in terms of gas is 1gal/36.7miles * 36.7kWhr/gal =1kwhr or 1kJoules/sec*3600Sec = 3.6x10^6 joules... so overall efficiency is 0.45/3.6 = 12.5% for this example... change the parameters to get other results... i.e. mass of car, mpg, average speed etc.. adonaldson@calbaptist.edu engineering prof"
The questioner replied to this answer with "Thanks. That's what I was looking for." It's too bad that he or she found it because it's completely wrong. The "engineering prof" calculated the kinetic energy of the moving vehicle and then somehow decided that that's the energy required to move the vehicle one mile. Of course, the kinetic energy of a given vehicle depends only on its speed and has nothing to do with how far the vehicle travels at that speed. To start from a standstill and accelerate to speed requires turning chemical potential energy into kinetic energy, but so does overcoming aerodynamic drag, rolling resistance, etc., not to mention the kinetic energy of the various rotating masses (flywheel, tires, etc.). All of this was ignored.
If this is truly an engineering prof., I grieve for our future. Of course, even if it isn't I'm not all that sanguine. Anyway, I'm sure I'll find plenty of material for my semi-regular session of poking fun at the published factual ignorance on the 'net.
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