Blame it on my ignorance of alcohol-related processes. Though of course, I go to CU, where that's supposedly a cardinal sin...
If by CU you mean Clemson University, then yes it is. You will be required to demonstrate alcohol proficiency as a prerequisite for your undergraduate degree.
I still have my lecture notes somewhere around here... or is that around here somewhere...
The patient feels, smells, tastes, and sees nothing whatsoever during the entire process.
If you have metal amalgam fillings in your teeth, you'll taste those.
Some people feel dizzy when they move into a 3 Tesla magnetic field. It's certainly noticeable.
The real magic behind MRI technology is that we humans were ever able to discover superconductivity, let alone get it to work to the point where we could store 27 MJ of energy in a magnet. The rest is just some minor piddling details of quantum mechanics and RF resonance.
GE's old platform was IRIX on SGI machines. The Octane was the last workstation before the new stuff came out. I've been playing around with the GEHC dist at work (I work where the magnets are built and tested) and was surprised to find a copy of the Gimp included. I imagine you could have some good hijinks on a slow scanning day (cooking up an MRI scan of Homer Simpson's brain comes to mind). There is also a full copy of xscreensaver and all the included screen hacks, which make it easier to burn up that free time.
A lot of goodies are missing from the distro though. I haven't found any of the games I usually expect to see (not even fortune!)
GE's Advantage Workstation (a dervish of a dual Xeon box) runs a variant of Linux. But before anyone starts anything about GNOME or KDE, it uses the ugly Motif widget set.
The humour of having imaging software use such an ugly environment is not lost on the developers either, it seems.
Actually, this is something we've discussed at work a lot. There is no easy answer AFAWK, as the magnetic field and/or the RF emissions would do nasty things to the chip, the patient, or both.
The magnetic field isn't the only problem here. Ever put an rfid (like the larger ones embedded in newer college id cards) in the microwave? Imagine something like that from the imaging coils. (A 3.0T RF amplifier can produce as much as 35kW ERP if you bypass the safety controls).
Now, if worldwide production is something like 25GW and the pulse lasts 10us, we have 25GW * 4 * 10us = 1MJ, a balievable finite quantity.
Your average hospital will have Atlas beat. A common 1.5 Tesla MRI magnet has a little over 6 MJ of electromotive energy stored in its main superconducting coil.
One of the newer 3.0 Tesla MRI units has over 27 MJ stored on its coil.
You can discharge this energy in less than 1 millisecond, but the resulting event (called a "quench") will mean having to replace most of the liquid helium and parts of the gas pressure relief system (which is destroyed by the rapid boiloff of LHe), an expensive proposition.
Note: These energy potentials were obtained via the E = I^2 * L method.
If you can flow liquid helium up your arm at room temperature, it's time to talk to your landlord ASAP.
The poster is probably just mistaking the instantly condensed nitrogen from the atmosphere for liquid helium. Liquid nitrogen (and oxygen the other gases in our atmosphere) runs down the plumbing of your helium container as the liquid boils off and escapes.
Having LN2 run down your arm is not very pleasant either, however. Stings like electric shock at first, and if it stops stinging you know you're in BIG trouble.
IANAP, but I am an MRI technician.
A side note: Liquid helium is very expensive to produce. The bulk of the cost of production is in harvesting the gas to compress down to liquid form. All the helium that exists on Earth is the product of eons of radioactive decay. When the liquid boils off, the escaping gas rises far above our reach. That's ironic, given that He is the second most abundant element in the universe... yet we have to pay more for it than for oil (around $10 per liter).
I work for a company that produces the superconducting magnets for MRI systems. -269.15 C is a common temperature inside the helium vessel. If the atmosphere (mostly N2, but some other stuff) gets into the vessel and freezes (contaminating it), then we might warm it up (with helium gas) to -90C to thaw and blow that other junk out.
I guess it would have been better to say "Chinese Team Heading for Coldest Natural Spot on Earth"
Note: Because of the low temperatures, we use Kelvin for temperatures at work. I've converted these to Celsius for your convenience.
Indeed, at work we have to use a cycle of LN2 first to precool the superconducting coil reservoir before we can actually begin pumping the LH in. (Otherwise it would simply boil off).
Liquid helium may be fairly inexpensive in small quantities, but at work we use around $4,000 worth per unit (plus all of the transportation and other costs -- our helium comes in on tanker trucks which are parked and drawn from until empty). These cores use lots of helium, and if something goes wrong they will vent the whole lot to the atmosphere in a matter of minutes. Of course, when that happens we may have up to 7600A of current to dissipate (which is a rather special consideration since that kind of current would melt the coil at normal resistance).
From what I understand, we have been using "small" amounts of our LH and LN2 for some of the classic cryogenic demonstrations around local schools. But, oddly enough, while we have a variety of SGI and PC-Linux based imaging workstations, no one around here seems to be into cryo-overclocking...
Imagine having to keep a vat of liquid nitrogen at your desk in order to use your computer! Notice the Fluke thermometer showing -105C (-157F). Now that is damned cold....
I've just put in for a job working with superconducting magnets, using LHe.
That's around 4K (-269C or -453F). Now that is damned damned damned damned cold....
If only liquid helium were as inexpensive as LN2.... We'd see some a quantumn leap in overclocking I'd bet... (pun intended!)
All that will mean is that ppl will have even less reason to purchase the crapfest that Hollywood produces than they do already
I wonder if you're giving the average consumer too much credit. Seems to me the average South Carolina resident will be only too happy to keep buying their crap. I imagine this is the same in many places. It's not the loss of a few former consumers, or even a lot of them. It's not even about selling movies and music. It's about control.
Who knows, people might even get out of their lounge rooms and go and do stuff for a change!
That's the best case scenario. But you know the average American... and you know how willing they are going to be to get off their couches.
It would be madness if Hollywood et al got their way, if only because as the article stated, Hollywood benefitted enourmously from sales of VCR.
Yes, it would be madness. But Hollywood doesn't care.
Now it is possible for them to sell read-only playback devices (such as the DVD) and if they ban all DVD-R, CD-R (+/-RW etc etc) then it won't affect their bottom line in the least. They can still profit from home videos that people can still play, but no one can record anything, except the organized criminals with their shops full of equipment... and people with legacy equipment. And once NTSC and PAL have been replaced by newer digital formats, that legacy equipment will become mostly useless. Hollywood would like nothing better.
You better stand up for your rights, or they're gonna kick you in the scrote.
Closed mine too today. I left them a nice comment in the "Reasons for Closing" section of the process.
Vote with your dollars if you don't like the policy, people! Griping on/. accomplishes nothing if you just go back to PayPal tomorrow because you must have those collectible Star Wars action figures!...even if you do fall for the Lucasian lure, make sure that the Princess Leia you bid on is fully clothed, or you may find yourself paying $500 more than you expected!
(In case you didn't RTFA: The new fines apply to BUYERS too!!!)
It's not your fault, blame the politicians, and those people who don't vote.
I do blame them, as well as blaming those who vote without being informed.
If I seem mad about all of this, it's because I am. I'll calm down and do something about it shortly.
*("Politicians" also includes those who are appointed rather than elected, like our current FCC Commissioners. End my shortwave listening will you? Grrr...)
First Fritz Hollings, and now Lindsey Graham! All the dumbest assholes seem to come from my state.
Hollings was pressured into retirement, but we need to get ready to vote that SOB Graham out now. (Only he isn't up for re-election this year.. too bad!)
It is my impression that the gap in the states is quite a bit larger.
Yes, quite a bit larger. Here in the states, they call it a "Tip Credit" and it is close to half of the minimum wage (which brings it down to around $3.50/hr for "tippable" employees, IIRC -- otherwise it's $5.15/hr). There are supposed to be some protections for cases where the employee does not make the difference in tips (which would reduce the tip credit), but you can guess how enforceable something like that is...
Slashdot Mirror
By Lenz's Law, the only way that you can get a magnetic field from electric current is to have a current input varying in the time domain (AC).
It's the other way around. The only way you can get electric current from a magnetic field is to have the field input varying in the time domain.
Otherwise how would my MRI magnets produce a magnetic field? (DC current is "stored" on the superconducting coil inside them)
Blame it on my ignorance of alcohol-related processes. Though of course, I go to CU, where that's supposedly a cardinal sin...
If by CU you mean Clemson University, then yes it is. You will be required to demonstrate alcohol proficiency as a prerequisite for your undergraduate degree.
I still have my lecture notes somewhere around here... or is that around here somewhere...
You're looking for this.
AFAIK Philips and Siemens both use Windows based platforms. Yuck.
The patient feels, smells, tastes, and sees nothing whatsoever during the entire process.
If you have metal amalgam fillings in your teeth, you'll taste those.
Some people feel dizzy when they move into a 3 Tesla magnetic field. It's certainly noticeable.
The real magic behind MRI technology is that we humans were ever able to discover superconductivity, let alone get it to work to the point where we could store 27 MJ of energy in a magnet. The rest is just some minor piddling details of quantum mechanics and RF resonance.
GE's old platform was IRIX on SGI machines. The Octane was the last workstation before the new stuff came out. I've been playing around with the GEHC dist at work (I work where the magnets are built and tested) and was surprised to find a copy of the Gimp included. I imagine you could have some good hijinks on a slow scanning day (cooking up an MRI scan of Homer Simpson's brain comes to mind). There is also a full copy of xscreensaver and all the included screen hacks, which make it easier to burn up that free time.
A lot of goodies are missing from the distro though. I haven't found any of the games I usually expect to see (not even fortune!)
GE's Advantage Workstation (a dervish of a dual Xeon box) runs a variant of Linux. But before anyone starts anything about GNOME or KDE, it uses the ugly Motif widget set.
The humour of having imaging software use such an ugly environment is not lost on the developers either, it seems.
Sure.. MRI should be able to scare away diabetes with the ridiculous sounds it makes..Gosh why did no one think of this before?
Tell me about it. I work in a factory testing the things. I hear those ridiculous sounds in my sleep, you insensitive clod!
Seriously though, the cryocoolers sound so much like chirping birds that wild birds keep coming inside and getting disoriented...
But if it does something about diagnosing diabetes, then I'll feel even more like I'm doing something worthwhile with my life.
They'll ban MRIs, thus putting me out of a job.
Actually, this is something we've discussed at work a lot. There is no easy answer AFAWK, as the magnetic field and/or the RF emissions would do nasty things to the chip, the patient, or both.
The magnetic field isn't the only problem here. Ever put an rfid (like the larger ones embedded in newer college id cards) in the microwave? Imagine something like that from the imaging coils. (A 3.0T RF amplifier can produce as much as 35kW ERP if you bypass the safety controls).
And all airline fatalaties occur not in the air but on the ground.
Payne Stewart, the golfer in that Learjet a few years back, and his crew died in the air of asphyxiation when the cabin depressurized.
I'm sure that has happened on a commercial airline sometime in the past as well.
So no, not all airline fatalities occur on the ground.
Now, if worldwide production is something like 25GW and the pulse lasts 10us, we have 25GW * 4 * 10us = 1MJ, a balievable finite quantity.
Your average hospital will have Atlas beat. A common 1.5 Tesla MRI magnet has a little over 6 MJ of electromotive energy stored in its main superconducting coil.
One of the newer 3.0 Tesla MRI units has over 27 MJ stored on its coil.
You can discharge this energy in less than 1 millisecond, but the resulting event (called a "quench") will mean having to replace most of the liquid helium and parts of the gas pressure relief system (which is destroyed by the rapid boiloff of LHe), an expensive proposition.
Note: These energy potentials were obtained via the E = I^2 * L method.
If you can flow liquid helium up your arm at room temperature, it's time to talk to your landlord ASAP.
The poster is probably just mistaking the instantly condensed nitrogen from the atmosphere for liquid helium. Liquid nitrogen (and oxygen the other gases in our atmosphere) runs down the plumbing of your helium container as the liquid boils off and escapes.
Having LN2 run down your arm is not very pleasant either, however. Stings like electric shock at first, and if it stops stinging you know you're in BIG trouble.
IANAP, but I am an MRI technician.
A side note: Liquid helium is very expensive to produce. The bulk of the cost of production is in harvesting the gas to compress down to liquid form. All the helium that exists on Earth is the product of eons of radioactive decay. When the liquid boils off, the escaping gas rises far above our reach. That's ironic, given that He is the second most abundant element in the universe... yet we have to pay more for it than for oil (around $10 per liter).
I was wondering if a test of loading OpenOffice.org writer would be usefull?
;)
Yes, but compiling the OpenOffice.org suite is the real time-trial challenge...
With BlueGene/L, I would hope that the compilation time would be measured in seconds, not hours like with my poor little (by comparison) Athlon.
It's not all that much, provided each line begins with a and ends with a .
I work for a company that produces the superconducting magnets for MRI systems. -269.15 C is a common temperature inside the helium vessel. If the atmosphere (mostly N2, but some other stuff) gets into the vessel and freezes (contaminating it), then we might warm it up (with helium gas) to -90C to thaw and blow that other junk out.
I guess it would have been better to say "Chinese Team Heading for Coldest Natural Spot on Earth"
Note: Because of the low temperatures, we use Kelvin for temperatures at work. I've converted these to Celsius for your convenience.
Indeed, at work we have to use a cycle of LN2 first to precool the superconducting coil reservoir before we can actually begin pumping the LH in. (Otherwise it would simply boil off).
Liquid helium may be fairly inexpensive in small quantities, but at work we use around $4,000 worth per unit (plus all of the transportation and other costs -- our helium comes in on tanker trucks which are parked and drawn from until empty). These cores use lots of helium, and if something goes wrong they will vent the whole lot to the atmosphere in a matter of minutes. Of course, when that happens we may have up to 7600A of current to dissipate (which is a rather special consideration since that kind of current would melt the coil at normal resistance).
From what I understand, we have been using "small" amounts of our LH and LN2 for some of the classic cryogenic demonstrations around local schools. But, oddly enough, while we have a variety of SGI and PC-Linux based imaging workstations, no one around here seems to be into cryo-overclocking...
Imagine having to keep a vat of liquid nitrogen at your desk in order to use your computer! Notice the Fluke thermometer showing -105C (-157F). Now that is damned cold....
I've just put in for a job working with superconducting magnets, using LHe.
That's around 4K (-269C or -453F). Now that is damned damned damned damned cold....
If only liquid helium were as inexpensive as LN2.... We'd see some a quantumn leap in overclocking I'd bet... (pun intended!)
No, this is capitalism for you.
That inspired me enough to have a little fun with the Gimp.
Capitalism Own4g3
ClearChannel also has a large ownership of XM. So even then, you're supporting the evil Republicans.
Want to hear more liberal commentary without supporting the evil right-winged controllers of distribution at the same time?
Buy a shortwave radio and listen to Radio Canada International and the BBC. (Or listen to their online streams for FREE).
Air America is just another sham, I've heard it. Even NPR is more interesting than AA.
All that will mean is that ppl will have even less reason to purchase the crapfest that Hollywood produces than they do already
I wonder if you're giving the average consumer too much credit. Seems to me the average South Carolina resident will be only too happy to keep buying their crap. I imagine this is the same in many places. It's not the loss of a few former consumers, or even a lot of them. It's not even about selling movies and music. It's about control.
Who knows, people might even get out of their lounge rooms and go and do stuff for a change!
That's the best case scenario. But you know the average American... and you know how willing they are going to be to get off their couches.
It would be madness if Hollywood et al got their way, if only because as the article stated, Hollywood benefitted enourmously from sales of VCR.
Yes, it would be madness. But Hollywood doesn't care.
Now it is possible for them to sell read-only playback devices (such as the DVD) and if they ban all DVD-R, CD-R (+/-RW etc etc) then it won't affect their bottom line in the least. They can still profit from home videos that people can still play, but no one can record anything, except the organized criminals with their shops full of equipment... and people with legacy equipment. And once NTSC and PAL have been replaced by newer digital formats, that legacy equipment will become mostly useless. Hollywood would like nothing better.
You better stand up for your rights, or they're gonna kick you in the scrote.
Buford "Mad Dog" Tannen
Closed mine too today. I left them a nice comment in the "Reasons for Closing" section of the process.
/. accomplishes nothing if you just go back to PayPal tomorrow because you must have those collectible Star Wars action figures! ...even if you do fall for the Lucasian lure, make sure that the Princess Leia you bid on is fully clothed, or you may find yourself paying $500 more than you expected!
Vote with your dollars if you don't like the policy, people! Griping on
(In case you didn't RTFA: The new fines apply to BUYERS too!!!)
An *empty* string certainly qualifies as "not to be" :-)
I failed "Fundamentals of Computer Science" the first time, you insensitive clod!
Oh wait... this isn't a poll. Carry on then.
It's not your fault, blame the politicians, and those people who don't vote.
I do blame them, as well as blaming those who vote without being informed.
If I seem mad about all of this, it's because I am. I'll calm down and do something about it shortly.
*("Politicians" also includes those who are appointed rather than elected, like our current FCC Commissioners. End my shortwave listening will you? Grrr...)
First Fritz Hollings, and now Lindsey Graham! All the dumbest assholes seem to come from my state.
Hollings was pressured into retirement, but we need to get ready to vote that SOB Graham out now. (Only he isn't up for re-election this year.. too bad!)
In closing, South Carolina sucks.
It is my impression that the gap in the states is quite a bit larger.
Yes, quite a bit larger. Here in the states, they call it a "Tip Credit" and it is close to half of the minimum wage (which brings it down to around $3.50/hr for "tippable" employees, IIRC -- otherwise it's $5.15/hr). There are supposed to be some protections for cases where the employee does not make the difference in tips (which would reduce the tip credit), but you can guess how enforceable something like that is...