And before the internet, 75% of 9-19 year olds have seen print/film pornography. It's not like porn didn't exist before the internet. Oh, and they messing up the results including the 18 and 19 year olds, who are legally allowed to look at porn.
I live in the UK and I'm not sure there is a legal age for viewing porn. It's probably illegal to give porn to children under 16, and might even be illegal to give it to 16 and 17 year olds. But the age of consent in the UK is 16 so it would be a bit perverse to prevent them looking at pictures but allow them to see the real thing.
When I was in my early teens topless pictures of 16 year olds were an every day event in daily newspapers. Sam Fox http://en.wikipedia.org/wiki/Samantha_Fox is the one that I remember.
I think the law has now changed so that such images are now "child pornography". I'm not sure whether these legacy images are now illegal or not. Could be interesting - someone storing an old copy of the Sun http://www.thesun.co.uk/ for some reason could probably end up on the sex offenders register.
Lena (lenna) http://en.wikipedia.org/wiki/Lenna is probably the single most famous image in image processing. It's also from the Miss Novermber 1972 playboy centerfold.
Every once in a blue moon, some poor person dies because he or she didn't get out of the burning car because of the belt. Then someone will stand up and say "See? I don't use them and if they didn't, they'd live as well. I drive carefully, I don't get into accidents, so I don't need them!"
However, if wearing a seat belt (using AV) makes you drive less carefully (run arbitrary untrusted executables) then you may not gain anything.
In the UK front seat belts were made compulsory IIRC in 1983. At the same time evidential breath testing was introduced. If you remove the estimated lives saved by having fewer drunk drivers then it appears that front seatbelts killed something like 200 extra people in 1984. Fewer car drivers did die but this was offset by increased cyclist and pedestrian deaths.
Single vehicle loss of control fatalities remains stubbornly at about 20% of all driving fatalities in the UK over multiple decades despite improvements in tyres, brakes and things like SIPS and airbags.
Likewise we hear that users in a corporate environment are more likely to "just run stuff" because the company IT infrastructure will protect them from their actions.
You failed to notice that he doesn't *return* anything from main, which is declared as 'int main'.
Doesn't have to return anything from main. But it must be defined as int main(void) or int main(int argc, char *argv[]) or equivalent.
5.1.2.2.1 Program startup for the valid definitions of main.
and
5.1.2.2.3 Program termination If the return type of the main function is a type compatible with int, a return from the initial... reaching the } that terminates main function returns a value of 0.
I leave firefox open all week at work and don't see these issues either.
However, I might not see this because I typically don't follow links within a tab but almost always right click "Open link in new tab" and then close that tab when I'm finished reading.
So my left most tab is always the front page of news.bbc.co.uk and other than refreshing the page it (almost) never changes.
All on the front unless there is any risk of the front wheel skidding.
The rear wheel will lift at maximum braking in most conditions before the front skids. (I don't think this is the case with motorbikes which have a heavy engine fairly low down which is why you will see bikers recommend 70/30 front rear split). The wet is more tricky to handle due to the rims starting with a film of water. Initially you can brake hard on the front because the brake blocks will slip. However suddenly the rim will dry and the blocks will stick, catapulting you over the bars (usually) or sliding along the floor if the front slips (typically if you are going over a manhole cover). So in the wet it's probably better to use both brakes initially with maybe a 50/50 split and then increase the front braking once the it bites. (and release the front brake completely as you go over any drain covers).
In an emergency stop from speed you can very lightly feather the rear brake. Blocks should barely touch the rims. You can then modulate the front brake based on the locking point of the rear wheel, as the rear wheel starts to lock you need to back off slightly on the front. (And yes you really can do this, especially when descending, although once was enough for me)
However, like the steer right to turn left inside a car that is going to left hook you (reverse for most countries) this is difficult to practice as you are riding right on the limits, these things have to be done at speed and it hurts if you get it wrong.
Maximum braking of a safety bicycle is around 0.7g. A recumbent is higher at around 0.8g in the dry. I've skidded the front wheels of my windcheetah and I've lifted the rear wheel of my tourer in the wet. I've also lifted the rear wheel of the windcheetah in the dry.
If you go high enough, people don't know very many primes. In fact, there are lists of the largest known primes. I'd wager that there are less than a few thousand known primes greater than 2^720k, probably a lot less.
Depends on whether you want provable primes or probable primes.
It's a five minute job to generate a few thousand probable primes >2^720k. Don't know what you'd do with them though.
And they will be prime, you can make the probability of them not being prime as small as you like - 1 in 2^100 should be enough.
But if you want to prove them prime then that is a different matter.
Every prime used in a real implementation of public key cryptography is a probable prime. The only reason for proving a number prime is to get yourself on the record books.
Although it doesn't say it here the matrix reduction phase usually requires a supercomputer with vast amounts of memory.
If they have cracked this just using Opterons then that is a major breakthrough and would make factoring SSL certificates within the target of zombie networks.
On the other hand, if this is 5 months of opteron + a week of supercomputer then that $1400 electricity bill for the opterons is going to be dwarfed by the costs of the supercomputer time (and probably electricity)
No. They are governed by whoever ICANN thinks ought to govern them. And if ICANN decides the US should administer.fr because the French didn't support the US in the Gulf war there is nothing France can do about it.
If the rest of the world really does decide to go without the US they can. If they decide that they will just copy the zone files from.com,.org,.net and.us from the existing root servers they can. And the US can decide not to support.fr,.de,.uk
But either there is going to be agreement over this eventually or there is going to be two separate DNS databases that _might_ stay in synch.
The rest of the world doesn't even need to tell people to start using different root nameservers. They can just require ISPs to redirect any traffic from the existing root nameservers to new root nameservers.
Many dns servers will automatically fetch a new zone file so this could very quickly propogate around the rest of the world permanently.
Short of having a friend on the "other side" who you can tunnel your traffic to we could well end up with two different views of the same internet.
ISTM that the "obviousness" of an invention is linked to whether I (or a person knowledgable in the field) could implement the idea just from the abstact.
So "prepaid billing" seems completely obvious.
But "1000MPG engine for a car" seems impossible (clearly it's thermodynamically possible) but I wonder if anybody could really get a patent for a "150MPG car by using energy saving and regenerative techniques" and then sit on it until GM/Ford/Toyota or whoever comes up with an implementation.
It would be like holding Ford liable for having a car that can exceed the speedlimit.
It's a fairly trivial (albeit expensive) exercise to design roads 2.0 + cars 2.0 so that speeding isn't possible.
But even if that is let go on "cost" grounds manufacturers would clearly be liable for cars that can exceed even the highest speed limit in a jurisdiction.
"But people might want to use their cars on the race track" I hear you say.
So software companies will sell software "Only for use on isolated networks" and "Not for use on internet connected equipment"
We have a (smallish) problem in the UK at the moment with kids on mini motorbikes. They are not road legal in the UK (apart from things like minimum age for riding a motorbike on the road these bikes apparently do not have brakes good enough to use on the road in any case) but I don't hear people calling for the engineer who designed them to be held liable for their illegal use on the road.
Exactly. The maximum possible thermodynamic (Carnot) efficiency for a car engine cycle is in the 30% range. This does not depend much on engine design or anything else for that matter, just the combustion temperature and the dead state (air) temperature. This is very basic physics.
Lookup Otto cycle in any decent thermodynamic textbook.
It's basically just the compression ratio that matters.
And the 30% is too low.
Marine diesels can achieve >50% thermal efficiency in practice.
My problem is that he claims to go from %35 to %97 efficiency.
I haven't RTFA. But if this is what is being claimed then it's snake oil plain and simple.
Lookup Otto cycle in any decent thermodynamics textbook. The theoretical thermodynamic efficiency of an IC engine is (approximately) limited only by the compression ratio.
About 70-80% is as good as you are going to get (and the higher end will be for diesel)
For comparison, the most efficient (marine) diesels can achieve slightly greater than 50% thermal efficiency in practice.
The 2 party system here in the US produces a majority party. That means they have a mandate and are thus far more accountable to their actions
The three party (four if you count "others") system in the UK also produces a majority party.
A vote for Labour was "worth" 3 times a vote for the Liberal Democrats or one of the other small parties.
A vote for the conservatives was "worth" 2/3 of a vote for Labour or twice a vote for the Liberal Democrats.
It's not that fewer people agree with you but that one third can dictate to the remaining two thirds.
Even when all the representatives of that 2/3 vote against Mr BLiar (e.g. ID cards) and even some of the Labour party do it still gets through parliament.
Cute. Very cute. All the cameras were "off". If true, that makes me suspicious if they were either deliberately turned off to avoid having to deal with pesky evidence, or the data simply erased.
Or maybe, just maybe, that Anonymous Coward is making things up.
I don't know how bittorrent works, and I've read Bram's blog on why he doesn't think ECC will work in practice but here is what I would have (naively) thought would be a possible implementation.
1. Break the file up into N blocks (I think this is what bittorrent does now)
2. Add N ECC blocks such that the entire file can be reconstructed from any N blocks (RS codes appear ideally suited to this - note that in general RS codes are used to detect+correct so N syndromes will only give N/2 corrections but in this case we already know the error locations because the block is missing and we can assume that blocks transmit correctly due to the SHA1 hash)
3. Use the existing bittorrent protocol to distribute the 2N blocks.
Now any client only needs _any_ N of the 2N blocks but, additionally, once the client has N blocks it can immediately generate the remaining N blocks for distribution to its peers.
At this point I would have thought there would be tweaks to the distribution protocol that could help speed up the distribution. But I guess that this "intuition" is probably wrong and all that would really have been achieved is a lot of extra complexity with maybe a performance gain in some odd corner cases that never happen in practice.
Slashdot Mirror
And before the internet, 75% of 9-19 year olds have seen print/film pornography. It's not like porn didn't exist before the internet. Oh, and they messing up the results including the 18 and 19 year olds, who are legally allowed to look at porn.
I live in the UK and I'm not sure there is a legal age for viewing porn. It's probably illegal to give porn to children under 16, and might even be illegal to give it to 16 and 17 year olds. But the age of consent in the UK is 16 so it would be a bit perverse to prevent them looking at pictures but allow them to see the real thing.
When I was in my early teens topless pictures of 16 year olds were an every day event in daily newspapers. Sam Fox http://en.wikipedia.org/wiki/Samantha_Fox is the one that I remember.
I think the law has now changed so that such images are now "child pornography". I'm not sure whether these legacy images are now illegal or not. Could be interesting - someone storing an old copy of the Sun http://www.thesun.co.uk/ for some reason could probably end up on the sex offenders register.
Lena (lenna) http://en.wikipedia.org/wiki/Lenna is probably the single most famous image in image processing. It's also from the Miss Novermber 1972 playboy centerfold.
Tim.
Every once in a blue moon, some poor person dies because he or she didn't get out of the burning car because of the belt. Then someone will stand up and say "See? I don't use them and if they didn't, they'd live as well. I drive carefully, I don't get into accidents, so I don't need them!"
However, if wearing a seat belt (using AV) makes you drive less carefully (run arbitrary untrusted executables) then you may not gain anything.
In the UK front seat belts were made compulsory IIRC in 1983. At the same time evidential breath testing was introduced. If you remove the estimated lives saved by having fewer drunk drivers then it appears that front seatbelts killed something like 200 extra people in 1984. Fewer car drivers did die but this was offset by increased cyclist and pedestrian deaths.
Single vehicle loss of control fatalities remains stubbornly at about 20% of all driving fatalities in the UK over multiple decades despite improvements in tyres, brakes and things like SIPS and airbags.
Likewise we hear that users in a corporate environment are more likely to "just run stuff" because the company IT infrastructure will protect them from their actions.
Tim.
It's K&R but it's not ISO. In ISO C defining your main function as main() or int main() has undefined behaviour.
You failed to notice that he doesn't *return* anything
... reaching the } that terminates main function returns a value of 0.
from main, which is declared as 'int main'.
Doesn't have to return anything from main. But it must be defined as int main(void) or int main(int argc, char *argv[]) or equivalent.
5.1.2.2.1 Program startup for the valid definitions of main.
and
5.1.2.2.3 Program termination
If the return type of the main function is a type compatible with int, a return from the initial
(from n2794.pdf)
On
The Origin of Species
by Means of Natural Selection,
or
The Preservation of Favoured Races in the Struggle for Life
I didn't know that. Thanks!
I leave firefox open all week at work and don't see these issues either.
However, I might not see this because I typically don't follow links within a tab but almost always right click "Open link in new tab" and then close that tab when I'm finished reading.
So my left most tab is always the front page of news.bbc.co.uk and other than refreshing the page it (almost) never changes.
All on the front unless there is any risk of the front wheel skidding.
The rear wheel will lift at maximum braking in most conditions before the front skids. (I don't think this is the case with motorbikes which have a heavy engine fairly low down which is why you will see bikers recommend 70/30 front rear split). The wet is more tricky to handle due to the rims starting with a film of water. Initially you can brake hard on the front because the brake blocks will slip. However suddenly the rim will dry and the blocks will stick, catapulting you over the bars (usually) or sliding along the floor if the front slips (typically if you are going over a manhole cover). So in the wet it's probably better to use both brakes initially with maybe a 50/50 split and then increase the front braking once the it bites. (and release the front brake completely as you go over any drain covers).
In an emergency stop from speed you can very lightly feather the rear brake. Blocks should barely touch the rims. You can then modulate the front brake based on the locking point of the rear wheel, as the rear wheel starts to lock you need to back off slightly on the front. (And yes you really can do this, especially when descending, although once was enough for me)
However, like the steer right to turn left inside a car that is going to left hook you (reverse for most countries) this is difficult to practice as you are riding right on the limits, these things have to be done at speed and it hurts if you get it wrong.
Maximum braking of a safety bicycle is around 0.7g. A recumbent is higher at around 0.8g in the dry. I've skidded the front wheels of my windcheetah and I've lifted the rear wheel of my tourer in the wet. I've also lifted the rear wheel of the windcheetah in the dry.
Fantastic Voyage (the book) was based on Fantastic Voyage (the screenplay) so the plot wasn't Asimov's.
However, Fantastic Voyage II is an Asimov original.
Perpetual Motion Machines
Shop on eBay and Save!
Discount Perpetual Motion Machines
www.eBay.com
If you go high enough, people don't know very many primes. In fact, there are lists of the largest known primes. I'd wager that there are less than a few thousand known primes greater than 2^720k, probably a lot less.
Depends on whether you want provable primes or probable primes.
It's a five minute job to generate a few thousand probable primes >2^720k. Don't know what you'd do with them though.
And they will be prime, you can make the probability of them not being prime as small as you like - 1 in 2^100 should be enough.
But if you want to prove them prime then that is a different matter.
Every prime used in a real implementation of public key cryptography is a probable prime. The only reason for proving a number prime is to get yourself on the record books.
Tim.
Although it doesn't say it here the matrix reduction phase usually requires a supercomputer with vast amounts of memory.
If they have cracked this just using Opterons then that is a major breakthrough and would make factoring SSL certificates within the target of zombie networks.
On the other hand, if this is 5 months of opteron + a week of supercomputer then that $1400 electricity bill for the opterons is going to be dwarfed by the costs of the supercomputer time (and probably electricity)
Tim.
No. They are governed by whoever ICANN thinks ought to govern them. And if ICANN decides the US should administer .fr because the French didn't support the US in the Gulf war there is nothing France can do about it.
.com, .org, .net and .us from the existing root servers they can. And the US can decide not to support .fr, .de, .uk
If the rest of the world really does decide to go without the US they can. If they decide that they will just copy the zone files from
But either there is going to be agreement over this eventually or there is going to be two separate DNS databases that _might_ stay in synch.
The rest of the world doesn't even need to tell people to start using different root nameservers. They can just require ISPs to redirect any traffic from the existing root nameservers to new root nameservers.
Many dns servers will automatically fetch a new zone file so this could very quickly propogate around the rest of the world permanently.
Short of having a friend on the "other side" who you can tunnel your traffic to we could well end up with two different views of the same internet.
Tim.
ISTM that the "obviousness" of an invention is linked to whether I (or a person knowledgable in the field) could implement the idea just from the abstact.
So "prepaid billing" seems completely obvious.
But "1000MPG engine for a car" seems impossible (clearly it's thermodynamically possible) but I wonder if anybody could really get a patent for a "150MPG car by using energy saving and regenerative techniques" and then sit on it until GM/Ford/Toyota or whoever comes up with an implementation.
Tim.
It would be like holding Ford liable for having a car that can exceed the speedlimit.
It's a fairly trivial (albeit expensive) exercise to design roads 2.0 + cars 2.0 so that speeding isn't possible.
But even if that is let go on "cost" grounds manufacturers would clearly be liable for cars that can exceed even the highest speed limit in a jurisdiction.
"But people might want to use their cars on the race track" I hear you say.
So software companies will sell software "Only for use on isolated networks" and "Not for use on internet connected equipment"
We have a (smallish) problem in the UK at the moment with kids on mini motorbikes. They are not road legal in the UK (apart from things like minimum age for riding a motorbike on the road these bikes apparently do not have brakes good enough to use on the road in any case) but I don't hear people calling for the engineer who designed them to be held liable for their illegal use on the road.
Exactly. The maximum possible thermodynamic (Carnot) efficiency for a car engine cycle is in the 30% range. This does not depend much on engine design or anything else for that matter, just the combustion temperature and the dead state (air) temperature. This is very basic physics.
Lookup Otto cycle in any decent thermodynamic textbook.
It's basically just the compression ratio that matters.
And the 30% is too low.
Marine diesels can achieve >50% thermal efficiency in practice.
Tim.
My problem is that he claims to go from %35 to %97 efficiency.
I haven't RTFA. But if this is what is being claimed then it's snake oil plain and simple.
Lookup Otto cycle in any decent thermodynamics textbook. The theoretical thermodynamic efficiency of an IC engine is (approximately) limited only by the compression ratio.
About 70-80% is as good as you are going to get (and the higher end will be for diesel)
For comparison, the most efficient (marine) diesels can achieve slightly greater than 50% thermal efficiency in practice.
Tim.
The 2 party system here in the US produces a majority party. That means they have a mandate and are thus far more accountable to their actions
The three party (four if you count "others") system in the UK also produces a majority party.
A vote for Labour was "worth" 3 times a vote for the Liberal Democrats or one of the other small parties.
A vote for the conservatives was "worth" 2/3 of a vote for Labour or twice a vote for the Liberal Democrats.
It's not that fewer people agree with you but that one third can dictate to the remaining two thirds.
Even when all the representatives of that 2/3 vote against Mr BLiar (e.g. ID cards) and even some of the Labour party do it still gets through parliament.
Erm...
A lot more people _didn't_ vote for Mr BLiar (via their electoral ward) than did.
IIRC Mr BLiar got about 36% of the vote and about 25% of the electorate. (70% turnout)
Cute. Very cute. All the cameras were "off". If true, that makes me suspicious if they were either deliberately turned off to avoid having to deal with pesky evidence, or the data simply erased.
Or maybe, just maybe, that Anonymous Coward is making things up.
http://news.bbc.co.uk/1/hi/uk/4175498.stm
"As the row over the shooting of Jean Charles de Menezes rages, the papers consider new claims from staff at Stockwell Tube station.
The Times says they insist CCTV cameras on the platform were working when police shot the Brazilian electrician.
Police officers are said to have told investigators no footage was available. "
I won't use the Natwest online banking because it requires the use of Java and Javascript (at least it did less than a year ago)
Any bank reasonably worried about security should not require either of these (and would recommend that they be switched off)
Barclays don't require Java or Javascript and their online banking isn't that hard to use so there really isn't any excuse.
Tim.
"The BBC is a unit of the British Government, and its musicians are thus Government employees."
"That's simplified to the point of complete innaccuracy."
Completely inaccurate? To quote Pauli, "It is not even wrong."
Using a (254,127) RS code over GF(2^8) it is possible to recover all 254 symbols from any 127 where each symbol would be a byte.
All 254 symbols are linearly independent
This would then be run in parallel for all bytes in a block.
I don't know how bittorrent works, and I've read Bram's blog on why he doesn't think ECC will work in practice but here is what I would have (naively) thought would be a possible implementation.
1. Break the file up into N blocks (I think this is what bittorrent does now)
2. Add N ECC blocks such that the entire file can be reconstructed from any N blocks (RS codes appear ideally suited to this - note that in general RS codes are used to detect+correct so N syndromes will only give N/2 corrections but in this case we already know the error locations because the block is missing and we can assume that blocks transmit correctly due to the SHA1 hash)
3. Use the existing bittorrent protocol to distribute the 2N blocks.
Now any client only needs _any_ N of the 2N blocks but, additionally, once the client has N blocks it can immediately generate the remaining N blocks for distribution to its peers.
At this point I would have thought there would be tweaks to the distribution protocol that could help speed up the distribution. But I guess that this "intuition" is probably wrong and all that would really have been achieved is a lot of extra complexity with maybe a performance gain in some odd corner cases that never happen in practice.
Not to gmail but to any email client you want to run on the box you have connected to.
AIUI gmail can be accessed via pop3/imap.