It seems to me it would be much harder to poison a filter that did Bayes by splitting email into word pairs or triplets and assigning ham and spam probabilities for each. That way the bad grammar and random word lists would be extra-bad. I suspect longer sequences would become harder and harder to foil. They might require extra training of the database, but if you're getting lots of spam that isn't really a problem. Perhaps the word sequence length could be configurable.
I seem to recall that recently the guy who looks after the debian packages for mplayer began building them with arts support because arts no longer depended on Qt. So although it doesn't care much about gtk I don't really think you can say it isn't cross-platform. Or am I missing something?
Absolutely. But most of the pro digital users tend to be photojournalists of one kind or another, whether for newspapers or glossies: digital is great in some cases due to the speed with which the image can get from lens to press and in other cases due to being able to check immediately whether or not the image you have sucks. I imagine for a photojournalist who's been sent halfway round the world on an assignment it must be a real boon to be able to check that you have all the images you need on the screen on your camera and then email them from that country without having to worry about airport X-rays on the return journey. I haven't heard of many artistic pro photographers using digital yet - I may be wrong, that's just the impression I get.
I wouldn't. Given that a reasonable sized office is maybe 6 metres across, at 61 inches and about 1300 by 768 this would be pixel-o-rama. I'll wait for the 4000x6000 version:-)
Frankly I don't care whether it's a millibar or ten. The basic physics of gases doesn't change significantly until you get to much lower pressures than that.
As far as UV goes there is no difference between that striking the Earth and that striking Mars, besides rate of photons. The individual photons are exactly the same (remember you only get one individual photon taking part in a given reaction, it either has sufficient energy or not, so that even at a low rate of UV photons you will get the same reaction occurring). As I'm sure you're aware the ozone layer isn't perfect. It has holes and even where the holes aren't UV still gets through. Like I said, plenty of UV reaches the surface to cause a noticeable reaction if one were going to occur.)
Sorry, this just isn't worth my time continuing. I wasn't trying to start an intellectual pissing contest and I haven't tried to quote out of context. Equally I'm not going to spend the rest of the night explaining chemistry.
where did I say that boiling water causes it to dissociate?
Let me refresh your memory: So, it would boil because there was not enough atmospheric pressure to keep it in liquid form?
Yep. [...]
The molecules simply decouple and turn into individual hydrogen and oxigen atoms
My physics lesson may have been third grade but it seems like you have one or two misconceptions that at the very least need clarifying before you give everyone else the benefit of your wisdom. To say there's "no atmospheric pressure" isn't true either. There's a millibar, which is low compared to sea-level pressure on Earth but nowhere near negligible. Gravity will have an effect on the escape veocity of gases near the top of the atmosphere but otherwise does not significantly affect the small-scale molecular kinetics. I must say I'm curious about your UV theory though. If UV makes water turn into hydrogen and oxygen why don't people ionise on a sunbed? Or on the beach? For that matter, why are there still oceans on Earth? Plenty of UV radiation reaches the Earth's surface. Perhaps you could supply some actual equations and figures to back up your claim? I'm sure I'd love to see them...
I disagree. Mars does not have enough of an atmosphere for this to happen at high altitude. It'll more than likely happen at surface level.
So what do you think is going to happen if ionization does take place? There will be a free OH- ion right next to a free H+ ion: they will recombine almost instantly. A millibar is not "negligible pressure" as you seem to think. Besides which, the main point I was arguing was your description of boiling as dissociation (apparently under any circumstances). You can quite easily dissociate liquid water by electrolysis (though at STP the oxygen and hydrogen given off will indeed be gaseous); however you can equally well boil water without dissociating it. The two phenomena are separate.
you do frequently find optically thin clouds of ice crystals
CO2 crystals, not H2O. You would have heard about it in the news by now if a spectrometer detected a cloud of water in Mars (or anywhere else for that matter).
Wrong again, there are both. How else do you suggest the water ice cap grows and shrinks seasonally? I suggest you try google://water clouds mars before embarassing yourself further.
As for water clouds on other planets, there are plenty. See (for example) Roos-Serote et al: Proximate Humid and Dry Regions in Jupiter's Atmosphere Indicate Complex Local Meteorology, submitted to Nature October 1999, or Irwin, P.G.J., S.B. Calcutt, F.W. Taylor, A. Baugh, S. Webster, C.A. Nixon and R.W. Carlson 2000. Evidence for the existence of a deep water cloud from the Galileo Near Infrared Mapping Spectrometer, Bulletin of the American Astronomical Society, 32, p 1007. We've definitely seen water clouds in the troposphere of Jupiter. Venus or Mercury don't have much if any water vapour in the atmosphere, but Saturn does. Uranus and Neptune also do, although they are very strange.
I've researched planetary atmospheres and subsequently taught physics for a while. Sorry for being rude, but while I'm more than happy to help people out when they don't understand the science and ask for an explanation there is little that enrages me more than people "teaching" others wrong science. It undermines much of the work that science teachers try to do every day. Please stop your misinformation.
Semantically I'm not sure. I tend to use the term "water vapour"; it seems less ambiguous. But when people point to the foggy cloud of water droplets just above a boiling kettle they tend to say "Ooh, look! Steam!"
Not at all. Much of the water is probably locked away in permafrost in the (very much sub-freezing point) crust. Any that does liquefy near the surface may boil off but that doesn't mean it has to form clouds. A tiny amount may see enough high-energy radiation near the top of the atmosphere to dissociate (in which case the hydrogen has a high probability to escape from the atmosphere) but it is far more likely to form tiny airborne ice crystals and be deposited on the surface again. In fact you can observe this happening every Martian year, when ice is deposited at the polar regions. (The question of why it occurs there rather than everywhere is a rather complicated one due to the Martian atmospheric circulation being very different to that of the Earth) You certainly wouldn't expect Earthlike clouds to form at the ~1mb SLP that you get on Mars: however if I remember correctly from my planetary atmospherics MPhys you do frequently find optically thin clouds of ice crystals.
Utter rubbish. Water doesn't dissociate into hydrogrn and oxygen just by being boiled. The interatomic forces holding the molecule together are not broken. You can make it dissociate by electrolysis but it does not happen through boiling. If it did it would be quite inadvisable to light a match anywhere near a kettle, given that a mixture of hydrogen and oxygen is just a bit flammable! Each water molecule is polarised (quite strongly as it happens): although it is overall electrically neutral, one end is rather positive and the other end is rather negative. You get residual interactions between the positive end of one molecule and the negative end of the next one along. When the water molecules are extremely cold they are held in a lattice structure by these residual dipole moments. This is ice. When you add some heat the water molecules jiggle around, and eventually have enough energy to break the lattice and move around freely, though they are still attracted to each other because of the electrical dipoles. This is water. Add some more heat energy and the jiggling water molecules move so fast that they have enough kinetic energy to break out of the energy well of the intermolecular bonds. They can move around at will and each molecule can go where it wants. This is water vapour. The temperature at which these changes occur depends on pressure for reasons that you can go and look up.
What you see as steam when a kettle boils is actually liquid water that cools and recondenses into countless tiny droplets above the kettle's spout.
What does this have to do with quantum mechanics? The uncertainty that causes unpredictability in the NS equations could just as well come from a classical system. Unless you entirely fill your system with sensors you can't know the initial conditions with perfect accuracy: there will be disturbances much bigger than quantum fluctuations that you will miss. It is true that quantum mechanics will turn subsequent system states into probability functions, but from a practical (or even hypothetically practical) point of view that's irrelevant. There isn't much point in predicting the weather if the entire {atmosphere, oceans and ground down to a considerable depth} has been replaced by sensors.
Thanks (and to the other respondents). I've been considering moving away from Virgin (awful service, awful support...) for a while now, it's good to get some positive testimonials for other services.
That could equally well describe a small meteor strike, possibly containing toxic or radioactive substances or landing on an area containing them in the geology, if you have to explain the hair and nails bits. And it doesn't seem to be predicting anything.
I think that's why "SPF" was a link to a site explaining all about it; you could try CTFL. Of course, nobody here ever reads the stories before posting much less clicks the links.
It's just called "The Queen's Speech", which isn't as ambiguous as it sounds because she only makes one speech to parliament per session. I think our Data Protection Act would help prevent outrageous abuses of confidential data like this: it can be a bit draconian[0] but this mess has just made me realise its good points!
[0] It has rather weird consequences, like making it almost impossible to arrange college reunions etc. for people who left before the Act: since personal data may only be used for the purpose for which it was originally collected mere registration data can't be used for that kind of thing, you have to fill out a separate "contact data for organising reunions" form (which is fine for current students, but a PITA for trying to get hold of people who never had to fill in such a form).
You don't even need a competent scripter. I wouldn't call myself a competent scripter and I certainly couldn't just write out the perl off the top of my head, but I could certainly work it out in five minutes using man regexp and a tiny bit of trial-and-error. The script would be a couple of lines.
Douglas Adams said pretty much exactly this in the Hitch-Hiker's Guide books: remember how the main qualification for Galactic President was to be as outrageous and attention-grabbing as possible so that no-one looked past that to see what was really going on?
But, just like the dophins, nobody took any notice.
I do own one. I've had good luck with mine-- even when I was using it in places I shouldn't. (technically, the weather station at Jungfraujoch is too far up to use a microdrive safely.)
No use for me, then. I'll stick with flash when I get my DSLR. It's likely to see conditions far more hostile than that - certainly higher. (OOI, what is it about height that causes problems? Something to do with the pressure I assume, but IANA hard drive engineer).
Oh, yeah. I'm sure the ancient sages 4000 years ago were writing all about implosion-style devices made using man-made unstable heavy elements, fallout, ionising radiation, neutron pulses etc.
If what you intended to say was "ancient Indian mythology talks about wars where lots of people can be killed at once" then I wish you'd stick to that. Unless they're describing the phenomena pretty accurately I suggest it's not the ancient sages that are describing nuclear war at all, but their present-day interpreters.
If you want this type of interface you could probably rig something up with Xnest. Arrange it so that when you run foo it runs an Xnested server with some minimal windowmanager and launches foo-real inside that.[0] Then you'll be able to minimize the Xnest window just like a single "container window" and have all the application windows bound within it. This also has the benefit that everybody else can continue to use foo in a non-MDI fashion.
[0] This would take a bit of work to set up but has the advantage of incredible customisability. I suspect you'd want a window manager like blackbox where the window dressing can be customised to match the rest of your desktop but which is small, fast and light and doesn't insist on littering itself with panels and docks. If you get anywhere with some sufficiently generic scripts I'd be interested to see you post them on freshmeat (not so much because I like this interface myself but because it demonstrates the flexibility [hackability?] of X.
Slashdot Mirror
It seems to me it would be much harder to poison a filter that did Bayes by splitting email into word pairs or triplets and assigning ham and spam probabilities for each. That way the bad grammar and random word lists would be extra-bad. I suspect longer sequences would become harder and harder to foil. They might require extra training of the database, but if you're getting lots of spam that isn't really a problem. Perhaps the word sequence length could be configurable.
I seem to recall that recently the guy who looks after the debian packages for mplayer began building them with arts support because arts no longer depended on Qt. So although it doesn't care much about gtk I don't really think you can say it isn't cross-platform. Or am I missing something?
Absolutely. But most of the pro digital users tend to be photojournalists of one kind or another, whether for newspapers or glossies: digital is great in some cases due to the speed with which the image can get from lens to press and in other cases due to being able to check immediately whether or not the image you have sucks. I imagine for a photojournalist who's been sent halfway round the world on an assignment it must be a real boon to be able to check that you have all the images you need on the screen on your camera and then email them from that country without having to worry about airport X-rays on the return journey.
I haven't heard of many artistic pro photographers using digital yet - I may be wrong, that's just the impression I get.
I wouldn't. Given that a reasonable sized office is maybe 6 metres across, at 61 inches and about 1300 by 768 this would be pixel-o-rama. I'll wait for the 4000x6000 version :-)
Frankly I don't care whether it's a millibar or ten. The basic physics of gases doesn't change significantly until you get to much lower pressures than that.
As far as UV goes there is no difference between that striking the Earth and that striking Mars, besides rate of photons. The individual photons are exactly the same (remember you only get one individual photon taking part in a given reaction, it either has sufficient energy or not, so that even at a low rate of UV photons you will get the same reaction occurring). As I'm sure you're aware the ozone layer isn't perfect. It has holes and even where the holes aren't UV still gets through. Like I said, plenty of UV reaches the surface to cause a noticeable reaction if one were going to occur.)
Sorry, this just isn't worth my time continuing. I wasn't trying to start an intellectual pissing contest and I haven't tried to quote out of context. Equally I'm not going to spend the rest of the night explaining chemistry.
Argh! Spam from the almighty. I'd like to see bogofilter block that!
Yes. They are capable of believing many mutually contradictory things, including ones that are entirely impossible. :-)
<grins, ducks & dodges the thunderbolts>
where did I say that boiling water causes it to dissociate?
Let me refresh your memory:
So, it would boil because there was not enough atmospheric pressure to keep it in liquid form?
Yep. [...]
The molecules simply decouple and turn into individual hydrogen and oxigen atoms
My physics lesson may have been third grade but it seems like you have one or two misconceptions that at the very least need clarifying before you give everyone else the benefit of your wisdom. To say there's "no atmospheric pressure" isn't true either. There's a millibar, which is low compared to sea-level pressure on Earth but nowhere near negligible. Gravity will have an effect on the escape veocity of gases near the top of the atmosphere but otherwise does not significantly affect the small-scale molecular kinetics. I must say I'm curious about your UV theory though. If UV makes water turn into hydrogen and oxygen why don't people ionise on a sunbed? Or on the beach? For that matter, why are there still oceans on Earth? Plenty of UV radiation reaches the Earth's surface. Perhaps you could supply some actual equations and figures to back up your claim? I'm sure I'd love to see them...
I disagree. Mars does not have enough of an atmosphere for this to happen at high altitude. It'll more than likely happen at surface level.
So what do you think is going to happen if ionization does take place? There will be a free OH- ion right next to a free H+ ion: they will recombine almost instantly. A millibar is not "negligible pressure" as you seem to think. Besides which, the main point I was arguing was your description of boiling as dissociation (apparently under any circumstances). You can quite easily dissociate liquid water by electrolysis (though at STP the oxygen and hydrogen given off will indeed be gaseous); however you can equally well boil water without dissociating it. The two phenomena are separate.
you do frequently find optically thin clouds of ice crystals
CO2 crystals, not H2O. You would have heard about it in the news by now if a spectrometer detected a cloud of water in Mars (or anywhere else for that matter).
Wrong again, there are both. How else do you suggest the water ice cap grows and shrinks seasonally? I suggest you try google://water clouds mars before embarassing yourself further.
As for water clouds on other planets, there are plenty. See (for example) Roos-Serote et al: Proximate Humid and Dry Regions in Jupiter's Atmosphere Indicate Complex Local Meteorology, submitted to Nature October 1999, or Irwin, P.G.J., S.B. Calcutt, F.W. Taylor, A. Baugh, S. Webster, C.A. Nixon and R.W. Carlson 2000. Evidence for the existence of a deep water cloud from the Galileo Near Infrared Mapping Spectrometer, Bulletin of the American Astronomical Society, 32, p 1007.
We've definitely seen water clouds in the troposphere of Jupiter. Venus or Mercury don't have much if any water vapour in the atmosphere, but Saturn does. Uranus and Neptune also do, although they are very strange.
I've researched planetary atmospheres and subsequently taught physics for a while. Sorry for being rude, but while I'm more than happy to help people out when they don't understand the science and ask for an explanation there is little that enrages me more than people "teaching" others wrong science. It undermines much of the work that science teachers try to do every day. Please stop your misinformation.
Semantically I'm not sure. I tend to use the term "water vapour"; it seems less ambiguous. But when people point to the foggy cloud of water droplets just above a boiling kettle they tend to say "Ooh, look! Steam!"
Not at all. Much of the water is probably locked away in permafrost in the (very much sub-freezing point) crust. Any that does liquefy near the surface may boil off but that doesn't mean it has to form clouds. A tiny amount may see enough high-energy radiation near the top of the atmosphere to dissociate (in which case the hydrogen has a high probability to escape from the atmosphere) but it is far more likely to form tiny airborne ice crystals and be deposited on the surface again. In fact you can observe this happening every Martian year, when ice is deposited at the polar regions. (The question of why it occurs there rather than everywhere is a rather complicated one due to the Martian atmospheric circulation being very different to that of the Earth) You certainly wouldn't expect Earthlike clouds to form at the ~1mb SLP that you get on Mars: however if I remember correctly from my planetary atmospherics MPhys you do frequently find optically thin clouds of ice crystals.
Utter rubbish. Water doesn't dissociate into hydrogrn and oxygen just by being boiled. The interatomic forces holding the molecule together are not broken. You can make it dissociate by electrolysis but it does not happen through boiling. If it did it would be quite inadvisable to light a match anywhere near a kettle, given that a mixture of hydrogen and oxygen is just a bit flammable!
Each water molecule is polarised (quite strongly as it happens): although it is overall electrically neutral, one end is rather positive and the other end is rather negative. You get residual interactions between the positive end of one molecule and the negative end of the next one along. When the water molecules are extremely cold they are held in a lattice structure by these residual dipole moments. This is ice. When you add some heat the water molecules jiggle around, and eventually have enough energy to break the lattice and move around freely, though they are still attracted to each other because of the electrical dipoles. This is water. Add some more heat energy and the jiggling water molecules move so fast that they have enough kinetic energy to break out of the energy well of the intermolecular bonds. They can move around at will and each molecule can go where it wants. This is water vapour. The temperature at which these changes occur depends on pressure for reasons that you can go and look up.
What you see as steam when a kettle boils is actually liquid water that cools and recondenses into countless tiny droplets above the kettle's spout.
This could be their new slogan:
:-)
grep: it's better than being hit by an earthquake
What does this have to do with quantum mechanics? The uncertainty that causes unpredictability in the NS equations could just as well come from a classical system. Unless you entirely fill your system with sensors you can't know the initial conditions with perfect accuracy: there will be disturbances much bigger than quantum fluctuations that you will miss. It is true that quantum mechanics will turn subsequent system states into probability functions, but from a practical (or even hypothetically practical) point of view that's irrelevant.
There isn't much point in predicting the weather if the entire {atmosphere, oceans and ground down to a considerable depth} has been replaced by sensors.
Good point. I know there's been a techno remix of RMS' "Free Software Song", but what about a trance remix of "I pronounce Linux lee'nux"?
Thanks (and to the other respondents). I've been considering moving away from Virgin (awful service, awful support...) for a while now, it's good to get some positive testimonials for other services.
That could equally well describe a small meteor strike, possibly containing toxic or radioactive substances or landing on an area containing them in the geology, if you have to explain the hair and nails bits. And it doesn't seem to be predicting anything.
Care to clarify which broadband ISPs do this?
I think that's why "SPF" was a link to a site explaining all about it; you could try CTFL. Of course, nobody here ever reads the stories before posting much less clicks the links.
It's just called "The Queen's Speech", which isn't as ambiguous as it sounds because she only makes one speech to parliament per session.
I think our Data Protection Act would help prevent outrageous abuses of confidential data like this: it can be a bit draconian[0] but this mess has just made me realise its good points!
[0] It has rather weird consequences, like making it almost impossible to arrange college reunions etc. for people who left before the Act: since personal data may only be used for the purpose for which it was originally collected mere registration data can't be used for that kind of thing, you have to fill out a separate "contact data for organising reunions" form (which is fine for current students, but a PITA for trying to get hold of people who never had to fill in such a form).
You don't even need a competent scripter. I wouldn't call myself a competent scripter and I certainly couldn't just write out the perl off the top of my head, but I could certainly work it out in five minutes using man regexp and a tiny bit of trial-and-error. The script would be a couple of lines.
Douglas Adams said pretty much exactly this in the Hitch-Hiker's Guide books: remember how the main qualification for Galactic President was to be as outrageous and attention-grabbing as possible so that no-one looked past that to see what was really going on?
But, just like the dophins, nobody took any notice.
I do own one. I've had good luck with mine-- even when I was using it in places I shouldn't. (technically, the weather station at Jungfraujoch is too far up to use a microdrive safely.)
No use for me, then. I'll stick with flash when I get my DSLR. It's likely to see conditions far more hostile than that - certainly higher. (OOI, what is it about height that causes problems? Something to do with the pressure I assume, but IANA hard drive engineer).
Oh, yeah. I'm sure the ancient sages 4000 years ago were writing all about implosion-style devices made using man-made unstable heavy elements, fallout, ionising radiation, neutron pulses etc.
If what you intended to say was "ancient Indian mythology talks about wars where lots of people can be killed at once" then I wish you'd stick to that. Unless they're describing the phenomena pretty accurately I suggest it's not the ancient sages that are describing nuclear war at all, but their present-day interpreters.
If you want this type of interface you could probably rig something up with Xnest. Arrange it so that when you run foo it runs an Xnested server with some minimal windowmanager and launches foo-real inside that.[0] Then you'll be able to minimize the Xnest window just like a single "container window" and have all the application windows bound within it. This also has the benefit that everybody else can continue to use foo in a non-MDI fashion.
[0] This would take a bit of work to set up but has the advantage of incredible customisability. I suspect you'd want a window manager like blackbox where the window dressing can be customised to match the rest of your desktop but which is small, fast and light and doesn't insist on littering itself with panels and docks. If you get anywhere with some sufficiently generic scripts I'd be interested to see you post them on freshmeat (not so much because I like this interface myself but because it demonstrates the flexibility [hackability?] of X.