The whole concept of pebble bed reactors is that they can't blow. Even a catestophic coolant lose doesn't result in a meltdown because the fuel is "diluted" in pebble form.
That assumes all of the pebbles are manufactured correctly so that the reactor behaves as predicted.
Pebble bed reactors are very intrigiung to me, but I cringe when I hear people describe them as fail safe.
Sometimes, 'fail safe' just means we haven't figured out all the failure modes yet.
Ah yes, intermittant problems that mysteriously go away.
Normal engineers spend months instrumenting and debugging those sort of problems, rather than picking the first correlation they notice and announcing that that was the solution.
Agreed, which is why the study Is A Good Thing. For the most part, all we have right now is anecdotal evidence.Which is why I said - "Proof? No - but enough to keep us all suspicious."
There are so many devices and so many variables it will be hard to ever prove conclusively that all these devices are safe. There is so little margin for error during the last couple hundred feet of a low vis autoland that we don't need proof that a device is harmful - we need proof that it's safe.
No, your eyes are the primary navigation signal for the last few thousand feet. In a Category 1 ILS (the vast majority of ILS installations and approaches), you get 200' MDA, which at 3 degree glidepath is 3800 feet from the touchdown point (well, technically the aim point, but let's not get into minutia about flares and such).
You're correct. I was referring to the last few thousand feet vertically, which, of course, was only clear to me.
If it's CATIII, though, all your eyes do is scare you at the last second. (For those not familiar with it, CATIII is an 'autoland' by redundant autopilots with NO requirement to even see the runway before landing.)
The big picture is that an acceptable deviation near the ground is much smaller than an acceptable deviation at altitude. Most aircraft use ILS for that last few thousand vertically, which is no time to have any uncertified electronics running near your ILS receiver. And in the future, near your GPS receiver, too.
it seems counter-intuitive to me (as aparently it did to your parent poster) that with all the redundant systems on an airplane, a simple recieve-only device could cause a problem
Even a receive-only device generates RF signals - leakage from the tuner section, which generates the frequency it needs to tune. An RF guy could expand on this. An FM radio in airplane may not generate a strong signal, but it's many orders of magnitude closer to the aircraft's antenna than a ground transmitter. You know the 108 on your FM dial? Well, 108-118 is used by VOR's and ILS's (nav signals), and 118 to around 135 for voice communications. IIRC, TV audio is near the FM dial, also. AM radio is just above the band used by ADF navigation (used less and less in air carrier navigation every day.) That's why AM/FM/TV is banned during all phases of flight, not just below 10,000 feet.
I know nothing about RF from digital devices, but have heard that it can be significant.
The entertainment stuff that goes into an aircraft is extensively tested. The stuff people bring on board is essentially an experiment. While RF interference may rare, the consequences at low altitude could be really, really bad. Hence, the ban below 10,000 feet.
I go on a road trip with three phones around me (not all mine) and a Garmin GPS and it works just fine.
So what? A lot of people smoke and don't get lung cancer. Your few hours of sporadically monitored GPS performance don't mean anything statistically.
They want you to use the expensive inflight phone
The inflight phones were removed from our fleet years ago.
It annoys others on the plane
True, but you don't need RF studies to prove that.
In the event of an accident you're phone, laptop, cd player, gameboy, etc is a nice loose projectile.
What does this have to do with RF? That's why your supposed to stow your carry-ons for takeoff and landing, the most likely time for an accident.
GPS is just one of many nav instruments in the airplane, and for all but a handful of airplanes and approaches, is not the primary nav signal used for the last few thousand feet (the ILS is.)
Over the years, we've had several anomalous nav indications that were cleared up after flight attendants had all passengers shut down electronic devices. Proof? No - but enough to keep us all suspicious.
3) Double-click on the resulting file to "open" it...and then for most users, you must also enter your Admin password.
Is it true that if you're running under the admin account, you won't get the admin password prompt? Some in the thread you linked to say so.
Most private (not lab) Macs I've dealt with are running under the admin account most of the time, and getting someone to double-click on what they think is a picture would be a pretty easy - especially since Mac users are fairly confident about the safety of their machines, and consider images 'safe.'
It's not a virus, but if it's true that the admin account won't get a password prompt, I think this could trick quite a few people easily.
Chet Raymo's 365 Starry Nights is a great, easy introduction to the night sky and astronomy. You don't read like a textbook, you just pick it up and read the day's entry. (Amazon link for convenience - I have no sales affiliation with them.)
Some day's entries are visual objects, some are binocular, some are telescope, and some are 'here's what's there if you could see it.'
A great book for the casually curious. You could call it 'astronomy bait.' (Star bait?)
I can't find it on google right now, but the first day that Los Angeles began using automatic plate recognition, they generated a new type of 'stupid criminal' story.
Some guy goes to a meeting with his probation officer, and parks in front of a squad car with the plate recognition equipment in it. The system pings his ride - which was stolen.
Wow. It even has the support of the 'Integrity Research Institute,' and all the resources of erols.com behind their website.
Integrity Research Institute (IRI) is a non-profit corporation dedicated to helping establish integrity in scientific research, primarily regarding the physics of energy, whether it is in the technical, human health, or environmental area.
Too bad NASA's funding funding for him dried up. What do they know about physics, any way?
Slashdot Mirror
I just couldn't figure out where to attach the wires.
Users with data like yours also had the following data...
the cleaning and cooking is done by my Stepford wife.
That assumes all of the pebbles are manufactured correctly so that the reactor behaves as predicted.
Pebble bed reactors are very intrigiung to me, but I cringe when I hear people describe them as fail safe.
Sometimes, 'fail safe' just means we haven't figured out all the failure modes yet.
Plans were announced to build a high volume refinery near Crawford, TX.
Ah yes, intermittant problems that mysteriously go away.
Normal engineers spend months instrumenting and debugging those sort of problems, rather than picking the first correlation they notice and announcing that that was the solution.
Agreed, which is why the study Is A Good Thing. For the most part, all we have right now is anecdotal evidence.Which is why I said - "Proof? No - but enough to keep us all suspicious."
There are so many devices and so many variables it will be hard to ever prove conclusively that all these devices are safe. There is so little margin for error during the last couple hundred feet of a low vis autoland that we don't need proof that a device is harmful - we need proof that it's safe.
No, your eyes are the primary navigation signal for the last few thousand feet. In a Category 1 ILS (the vast majority of ILS installations and approaches), you get 200' MDA, which at 3 degree glidepath is 3800 feet from the touchdown point (well, technically the aim point, but let's not get into minutia about flares and such).
You're correct. I was referring to the last few thousand feet vertically, which, of course, was only clear to me.
If it's CATIII, though, all your eyes do is scare you at the last second. (For those not familiar with it, CATIII is an 'autoland' by redundant autopilots with NO requirement to even see the runway before landing.)
The big picture is that an acceptable deviation near the ground is much smaller than an acceptable deviation at altitude. Most aircraft use ILS for that last few thousand vertically, which is no time to have any uncertified electronics running near your ILS receiver. And in the future, near your GPS receiver, too.
Disclaimer: IANARFE (I am not an RF engineer)
it seems counter-intuitive to me (as aparently it did to your parent poster) that with all the redundant systems on an airplane, a simple recieve-only device could cause a problem
Even a receive-only device generates RF signals - leakage from the tuner section, which generates the frequency it needs to tune. An RF guy could expand on this. An FM radio in airplane may not generate a strong signal, but it's many orders of magnitude closer to the aircraft's antenna than a ground transmitter. You know the 108 on your FM dial? Well, 108-118 is used by VOR's and ILS's (nav signals), and 118 to around 135 for voice communications. IIRC, TV audio is near the FM dial, also. AM radio is just above the band used by ADF navigation (used less and less in air carrier navigation every day.) That's why AM/FM/TV is banned during all phases of flight, not just below 10,000 feet.
I know nothing about RF from digital devices, but have heard that it can be significant.
The entertainment stuff that goes into an aircraft is extensively tested. The stuff people bring on board is essentially an experiment. While RF interference may rare, the consequences at low altitude could be really, really bad. Hence, the ban below 10,000 feet.
So what? A lot of people smoke and don't get lung cancer. Your few hours of sporadically monitored GPS performance don't mean anything statistically.
They want you to use the expensive inflight phone
The inflight phones were removed from our fleet years ago.
It annoys others on the plane
True, but you don't need RF studies to prove that.
In the event of an accident you're phone, laptop, cd player, gameboy, etc is a nice loose projectile.
What does this have to do with RF? That's why your supposed to stow your carry-ons for takeoff and landing, the most likely time for an accident.
GPS is just one of many nav instruments in the airplane, and for all but a handful of airplanes and approaches, is not the primary nav signal used for the last few thousand feet (the ILS is.)
Over the years, we've had several anomalous nav indications that were cleared up after flight attendants had all passengers shut down electronic devices. Proof? No - but enough to keep us all suspicious.
Is it true that if you're running under the admin account, you won't get the admin password prompt? Some in the thread you linked to say so.
Most private (not lab) Macs I've dealt with are running under the admin account most of the time, and getting someone to double-click on what they think is a picture would be a pretty easy - especially since Mac users are fairly confident about the safety of their machines, and consider images 'safe.'
It's not a virus, but if it's true that the admin account won't get a password prompt, I think this could trick quite a few people easily.
Right-click -> 'Open with Preview' from now on?
You misspelled 'bricks of marijuana.'
It's just a global coincidence.
And then the creative juices will get flowing again.
Just not for very long.
Some day's entries are visual objects, some are binocular, some are telescope, and some are 'here's what's there if you could see it.'
A great book for the casually curious. You could call it 'astronomy bait.' (Star bait?)
Maybe somebody can suggest a good anti-spyware program for the Mac.
"I love it when a joke comes together."
Some guy goes to a meeting with his probation officer, and parks in front of a squad car with the plate recognition equipment in it. The system pings his ride - which was stolen.
Pretty convenient for the cops.
He's right. But those applications are usually called 'viruses,' 'trojans,' or 'worms,' and their authors face jail time when they're caught.
I do not think that word means what you think it means.
See if their lips are moving.
Let me guess, that and a few million dollars away. You can get in on the ground floor.
Halliburton now owns the sun.
Too bad NASA's funding funding for him dried up. What do they know about physics, any way?