Doesn't it bother you that you have so many faulty products that you have to return to the shop? Sounds to me like they're selling pretty poor quality stuff there.
The described experiment however was about the surface and the interaction with the air flow. How the surface irregularties were made, that was not the subject of study here. After they figure out what those dimples should look like, then the next step is indeed to talk to materials scientists on what material would be suitable and how it could be processed.
You exactly confirm my point. Closed circuits - I didn't say purpose built. And yes Macau is really scary to watch - when they're racing it's even scarier than normal traffic there (but nothing compared to regular traffic on the mainland).
Highways are a special case as they are specifically designed to come without surprises, and to accommodate traffic at high speed. Yet what you say is very interesting - any explanation on why the number of accidents decreased?
But note that it doesn't make my statement "bullshit", I stated "in general" not just because as I know there are situations where it's different, and highways are simply the safest roads out there. The safest time on a highway is when the traffic has come to a standstill, like when you're in a traffic jam (yes yes yes the tail of the jam is a major problem and jams should be prevented but I'm not talking about that, I'm talking about when you actually are in a jam). Very low speed, extremely low risk of accidents (and extremely little damage in case people still manage to have an accident).
My best guess: their equipment could not make it better than that.
This sounds a bit like a professor learned something interesting about how these scorpions are not affected by the sand storms, and out of curiousity tries to find out what causes it. They went for shopping in the local pet shops, got themselves a few scorpions, took samples of the armour, and went to work with that. Put it under a microscope, add UV light (both pretty standard equipment), then made a laser scan of the surface (not so standard equipment, but they likely have it for other purposes or asked another department in the university do do it for them), and then tried to recreate the surface as well as they could with their existing equipment for a sandblasting experiment.
Buying special equipment for a single experiment done out of simple curiousity is usually not worth it. You use what you have, make the best out of it, and now they have some positive, promising results that's the time to maybe find an industry partner to invest in the equipment that can make an exact replica and continue to do experiments.
From police statistics it is proven that people that speed have a higher risk of accidents. It's a simple as that.
Higher than what?
Higher than people that do not speed. And while it may not be a primary cause, many accidents only happen because of a multitude of causes coming together at the wrong place and the wrong time. Speeding is one of them.
lower speed makes roads safer
Yet out here in the real world, motorways are the safest roads in Britain,
That's why I said "in general". I know motorways are the safest roads, that's pretty much all over the world, because they're designed to come without any surprises. So no traffic lights, no slow traffic (there is a minimum speed), no sharp corners, etc.
There is a very good reason for limiting the speed of trucks, and that is vehicle control. Trucks, especially when laden full, are heavy and as such at speed pack a lot of energy. Yes when laden they brake faster than when empty, but those brakes also have to absorb an enormous amount of energy, and there is a limit to what they can absorb before overheating and breaking down. At speed a heavy vehicle is also prone to instability - it's hard to make a vehicle strong/stiff enough to handle the enormous forces that come when a 40-ton trailer is hauled over a bump in the road at high speed. I have talked to many a truck driver, and while many will say the standard 80 km/hr limit is too low, not many are willing to go much over it. The normal 120 km/hr passenger vehicle speed they won't do, unless not hauling a trailer maybe.
Metallurgy still exists as name, it's just part of materials science. Many people studying materials science will specialise in a family of materials such as ceramics, metallurgy or polymers.
This is not material science, this is aerodynamics and fluid dynamics. Material science is about the properties of the material itself: strength, flexibility, conductivity, creep, fatigue, etc, and about the processing of a material. This study is about the surface of the material; the underlying material doesn't matter much, they used metal probably simply because they are familiar with it and have the equipment to make the desired shapes out of it.
That doesn't make this study, or material science, any less interesting - but if you're interested in these surface experiments, materials science is not where you should look first.
In this scorpion-skin situation I wouldn't be surprised if the surface drag is reduced.
Two reasons. The first is that the skin reduces erosion by the sand, which implies to me that the sand is kept away from the skin, again suggesting a thicker boundary layer, and that may decrease drag forces.
The second reason: the shark skin effect. A while ago there were these shark skin swimsuits, purportedly increasing the performance of swimmers by reducing surface drag. The shape of a shark (and most fish) are similar to aircraft in that they are highly streamlined and have little wake, making surface drag again dominant. If that works in water, it could also work in air.
Anyway it sounds like a straightforward experiment to test this: create two identical shapes (ball, wing, whatever), one with a polished surface and one with a dimpled/scratched surface, and put both in a wind tunnel. With or without sand.
From police statistics it is proven that people that speed have a higher risk of accidents. It's a simple as that.
Even if you pay better attention to the road, the higher speed means less reaction time, longer braking distance, and generally higher speed the moment you actually hit something making damage worse. Also if you're doing say 100 km/h on a road with an 80 km/h limit, other traffic may easily misjudge your speed, and try to make a turn in front of you when there is actually not enough time to do so. Or they simply see you coming around the corner too late, and with your too high speed you do not have enough time to stop to prevent an accident.
Generalising: lower speed makes roads safer. Taken to the extreme to make the point: at walking speed not much can happen, and if something happens the damage is minimal.
My current supplier is actually 2G only. With data limited to GPRS options. And it seems they're doing pretty well in their market, not having to maintain a 3G network and paying for the licenses does keep your costs down.
As I don't use mobile data, a year or two back ago I switched from 3G back to 2G. Not only are voice plans much cheaper, I don't notice any quality difference (shops will tell you that 3G has superior call quality - well I had less problems with reception after the switch back to 2G!) and battery life of the phone is far better. Also my phone didn't heat up so badly anymore.
Your MacBook can also do with more modern batteries, which may have double capacity what your old laptop had. Hard to compare. When I bought my iBook about eight years ago I could get 5, and dimming the screen up to 6 hours battery life out of it. Pretty good for the time. I don't think current Apple laptops can do 15 hours now, have yet to see even a netbook that betters 8-9 hours.
It's MS. First see, then believe. Great if it comes true (as it would give a boost to ARM based devices). Wouldn't be the first major rumoured feature/development that doesn't come true. And probably they have a much harder job than Apple has - if it's a port to begin with and not a ground-up rewrite.
ARM is quickly getting more and more powerful. Modern Intel chips are total overkill for by now 99% of common tasks - it makes sense to me that laptop makers would look into less power hungry chips that are powerful enough to build a next-generation laptop.
It won't be a speed monster, but it should be good enough for normal business work: e-mail, documents, web surfing - and many businessmen already do this on their iPads. Having an actual laptop (with the advantage of a real keyboard and the clamshell design that allows you to raise the screen) which supports desktop-type software and the battery life and instant-on of an iPad would be great. Best of both worlds.
Unfortunately we'll only see such a laptop from Apple, or from players that dare to go Linux (Asus would be a candidate for that), as I don't see Windows on ARM any time soon.
And considering an intern could port a complete OS port in a mere 12 weeks, shows how portable it is. This person presumably had never touched the OS-X source before, yet manages to pull it off. And indeed I recall rumours that OS-X was running on Intel from before the time the rumours came that Apple was planning to switch to Intel. I suppose portability is simply part of the demands by management. I don't think Microsoft will have such an easy time if they were ever to switch to another architecture.
And those driver issues: no surprise. That's by nature fairly low-level stuff talking directly to hardware so will need more work. Not counting third-party drivers of course.
A password so long and complex that you can not remember it (say a string of 20 random characters/letters/symbols), which is written on a paper. Destruction of the password can then be done the way you just described yourself.
I think what this case demonstrates, is the need for a duress password. Enter it and bam. Unrecoverably locked. Then it would be for the prosecution to prove that you deliberately destroyed evidence.
Sounds easy to prove.
There was evidence (in the encrypted file - unknown what evidence was there, which is why it had to be inspected it, and it's destroyed now, and that was done deliberately as with the real password the encryption software would never destroy your data).
Of course you will NOT enter the password on your own computer, at least not without having a bit-for-bit image of the hard disk contents - standard forensics. So if you give them such a password, the encrypted file is altered (because of the destruction process), and then it's of course very easy to prove that you deliberately tried to destroy evidence.
And that is exactly why I DON'T change my passwords all the time. My passwords are my secret, and mine alone, and I will use them until I know one is compromised.
Changing them all the time does not prevent a password from being compromised.
I must agree with the general statement that if someone was convicted under a then-valid law, the conviction stands. This is basically the same principle that a law can not be retro-active: if you do something today that is outlawed tomorrow, you can not be prosecuted for it. And punishments generally are to be given according to what was in the law the moment a crime was committed, not what is in the law when the verdict is given - like some time ago when a driver was prosecuted and convicted for drunk driving, he was sentenced according to the law when the crime was committed, and not according to the new law with much harsher sentences (doubled jail times and so) that came into force a week or two later.
But what happens to a criminal record in such a case where a law is abolished? If you are prosecuted and convicted for a crime that is later not a crime anymore: to me it sounds quite reasonable that while the conviction is not overturned (it was a valid conviction at the time), but the person's criminal record may be cleared of that crime.
The same for punishments: say someone commits a crime, gets a 5-year jail sentence for that, but two years into his jail time the laws change and the crime is not a crime anymore. Will they be released or do they have to continue serving the punishment? Again it sounds reasonable to release them the moment the new law comes in force.
More complex is the case for return of taken property, including paid fines. That's often simply impossible to do for practical reasons.
China is a country that is as close to atheist as you can get, and that is as close to banning religions as you can get. Most religions to this day are effectively banned, or highly controlled. People are prosecuted for having the "wrong" religious beliefs there.
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Doesn't it bother you that you have so many faulty products that you have to return to the shop? Sounds to me like they're selling pretty poor quality stuff there.
The described experiment however was about the surface and the interaction with the air flow. How the surface irregularties were made, that was not the subject of study here. After they figure out what those dimples should look like, then the next step is indeed to talk to materials scientists on what material would be suitable and how it could be processed.
You exactly confirm my point. Closed circuits - I didn't say purpose built. And yes Macau is really scary to watch - when they're racing it's even scarier than normal traffic there (but nothing compared to regular traffic on the mainland).
Right. And that's why races are done on public roads, instead of on closed circuits, right?
Highways are a special case as they are specifically designed to come without surprises, and to accommodate traffic at high speed. Yet what you say is very interesting - any explanation on why the number of accidents decreased?
But note that it doesn't make my statement "bullshit", I stated "in general" not just because as I know there are situations where it's different, and highways are simply the safest roads out there. The safest time on a highway is when the traffic has come to a standstill, like when you're in a traffic jam (yes yes yes the tail of the jam is a major problem and jams should be prevented but I'm not talking about that, I'm talking about when you actually are in a jam). Very low speed, extremely low risk of accidents (and extremely little damage in case people still manage to have an accident).
My best guess: their equipment could not make it better than that.
This sounds a bit like a professor learned something interesting about how these scorpions are not affected by the sand storms, and out of curiousity tries to find out what causes it. They went for shopping in the local pet shops, got themselves a few scorpions, took samples of the armour, and went to work with that. Put it under a microscope, add UV light (both pretty standard equipment), then made a laser scan of the surface (not so standard equipment, but they likely have it for other purposes or asked another department in the university do do it for them), and then tried to recreate the surface as well as they could with their existing equipment for a sandblasting experiment.
Buying special equipment for a single experiment done out of simple curiousity is usually not worth it. You use what you have, make the best out of it, and now they have some positive, promising results that's the time to maybe find an industry partner to invest in the equipment that can make an exact replica and continue to do experiments.
From police statistics it is proven that people that speed have a higher risk of accidents. It's a simple as that.
Higher than what?
Higher than people that do not speed. And while it may not be a primary cause, many accidents only happen because of a multitude of causes coming together at the wrong place and the wrong time. Speeding is one of them.
lower speed makes roads safer
Yet out here in the real world, motorways are the safest roads in Britain,
That's why I said "in general". I know motorways are the safest roads, that's pretty much all over the world, because they're designed to come without any surprises. So no traffic lights, no slow traffic (there is a minimum speed), no sharp corners, etc.
There is a very good reason for limiting the speed of trucks, and that is vehicle control. Trucks, especially when laden full, are heavy and as such at speed pack a lot of energy. Yes when laden they brake faster than when empty, but those brakes also have to absorb an enormous amount of energy, and there is a limit to what they can absorb before overheating and breaking down. At speed a heavy vehicle is also prone to instability - it's hard to make a vehicle strong/stiff enough to handle the enormous forces that come when a 40-ton trailer is hauled over a bump in the road at high speed. I have talked to many a truck driver, and while many will say the standard 80 km/hr limit is too low, not many are willing to go much over it. The normal 120 km/hr passenger vehicle speed they won't do, unless not hauling a trailer maybe.
Metallurgy still exists as name, it's just part of materials science. Many people studying materials science will specialise in a family of materials such as ceramics, metallurgy or polymers.
This is not material science, this is aerodynamics and fluid dynamics. Material science is about the properties of the material itself: strength, flexibility, conductivity, creep, fatigue, etc, and about the processing of a material. This study is about the surface of the material; the underlying material doesn't matter much, they used metal probably simply because they are familiar with it and have the equipment to make the desired shapes out of it.
That doesn't make this study, or material science, any less interesting - but if you're interested in these surface experiments, materials science is not where you should look first.
In this scorpion-skin situation I wouldn't be surprised if the surface drag is reduced.
Two reasons. The first is that the skin reduces erosion by the sand, which implies to me that the sand is kept away from the skin, again suggesting a thicker boundary layer, and that may decrease drag forces.
The second reason: the shark skin effect. A while ago there were these shark skin swimsuits, purportedly increasing the performance of swimmers by reducing surface drag. The shape of a shark (and most fish) are similar to aircraft in that they are highly streamlined and have little wake, making surface drag again dominant. If that works in water, it could also work in air.
Anyway it sounds like a straightforward experiment to test this: create two identical shapes (ball, wing, whatever), one with a polished surface and one with a dimpled/scratched surface, and put both in a wind tunnel. With or without sand.
Just keeping their costs down, so their customers can save more on premiums.
From police statistics it is proven that people that speed have a higher risk of accidents. It's a simple as that.
Even if you pay better attention to the road, the higher speed means less reaction time, longer braking distance, and generally higher speed the moment you actually hit something making damage worse. Also if you're doing say 100 km/h on a road with an 80 km/h limit, other traffic may easily misjudge your speed, and try to make a turn in front of you when there is actually not enough time to do so. Or they simply see you coming around the corner too late, and with your too high speed you do not have enough time to stop to prevent an accident.
Generalising: lower speed makes roads safer. Taken to the extreme to make the point: at walking speed not much can happen, and if something happens the damage is minimal.
In US maybe.
My current supplier is actually 2G only. With data limited to GPRS options. And it seems they're doing pretty well in their market, not having to maintain a 3G network and paying for the licenses does keep your costs down.
As I don't use mobile data, a year or two back ago I switched from 3G back to 2G. Not only are voice plans much cheaper, I don't notice any quality difference (shops will tell you that 3G has superior call quality - well I had less problems with reception after the switch back to 2G!) and battery life of the phone is far better. Also my phone didn't heat up so badly anymore.
Your MacBook can also do with more modern batteries, which may have double capacity what your old laptop had. Hard to compare. When I bought my iBook about eight years ago I could get 5, and dimming the screen up to 6 hours battery life out of it. Pretty good for the time. I don't think current Apple laptops can do 15 hours now, have yet to see even a netbook that betters 8-9 hours.
It's MS. First see, then believe. Great if it comes true (as it would give a boost to ARM based devices). Wouldn't be the first major rumoured feature/development that doesn't come true. And probably they have a much harder job than Apple has - if it's a port to begin with and not a ground-up rewrite.
ARM is quickly getting more and more powerful. Modern Intel chips are total overkill for by now 99% of common tasks - it makes sense to me that laptop makers would look into less power hungry chips that are powerful enough to build a next-generation laptop.
It won't be a speed monster, but it should be good enough for normal business work: e-mail, documents, web surfing - and many businessmen already do this on their iPads. Having an actual laptop (with the advantage of a real keyboard and the clamshell design that allows you to raise the screen) which supports desktop-type software and the battery life and instant-on of an iPad would be great. Best of both worlds.
Unfortunately we'll only see such a laptop from Apple, or from players that dare to go Linux (Asus would be a candidate for that), as I don't see Windows on ARM any time soon.
And considering an intern could port a complete OS port in a mere 12 weeks, shows how portable it is. This person presumably had never touched the OS-X source before, yet manages to pull it off. And indeed I recall rumours that OS-X was running on Intel from before the time the rumours came that Apple was planning to switch to Intel. I suppose portability is simply part of the demands by management. I don't think Microsoft will have such an easy time if they were ever to switch to another architecture.
And those driver issues: no surprise. That's by nature fairly low-level stuff talking directly to hardware so will need more work. Not counting third-party drivers of course.
A password so long and complex that you can not remember it (say a string of 20 random characters/letters/symbols), which is written on a paper. Destruction of the password can then be done the way you just described yourself.
I think what this case demonstrates, is the need for a duress password. Enter it and bam. Unrecoverably locked. Then it would be for the prosecution to prove that you deliberately destroyed evidence.
Sounds easy to prove.
There was evidence (in the encrypted file - unknown what evidence was there, which is why it had to be inspected it, and it's destroyed now, and that was done deliberately as with the real password the encryption software would never destroy your data).
Of course you will NOT enter the password on your own computer, at least not without having a bit-for-bit image of the hard disk contents - standard forensics. So if you give them such a password, the encrypted file is altered (because of the destruction process), and then it's of course very easy to prove that you deliberately tried to destroy evidence.
And that is exactly why I DON'T change my passwords all the time. My passwords are my secret, and mine alone, and I will use them until I know one is compromised.
Changing them all the time does not prevent a password from being compromised.
So you'd better never go for a vacation or so. Where you don't go and enter all your passwords every single day.
And it still isn't even clear who "won."
Of course it's clear who won: no-one. There are no winners in war. Just one party that loses even more than the other.
The issue raises a few questions to me.
I must agree with the general statement that if someone was convicted under a then-valid law, the conviction stands. This is basically the same principle that a law can not be retro-active: if you do something today that is outlawed tomorrow, you can not be prosecuted for it. And punishments generally are to be given according to what was in the law the moment a crime was committed, not what is in the law when the verdict is given - like some time ago when a driver was prosecuted and convicted for drunk driving, he was sentenced according to the law when the crime was committed, and not according to the new law with much harsher sentences (doubled jail times and so) that came into force a week or two later.
But what happens to a criminal record in such a case where a law is abolished? If you are prosecuted and convicted for a crime that is later not a crime anymore: to me it sounds quite reasonable that while the conviction is not overturned (it was a valid conviction at the time), but the person's criminal record may be cleared of that crime.
The same for punishments: say someone commits a crime, gets a 5-year jail sentence for that, but two years into his jail time the laws change and the crime is not a crime anymore. Will they be released or do they have to continue serving the punishment? Again it sounds reasonable to release them the moment the new law comes in force.
More complex is the case for return of taken property, including paid fines. That's often simply impossible to do for practical reasons.
China is a country that is as close to atheist as you can get, and that is as close to banning religions as you can get. Most religions to this day are effectively banned, or highly controlled. People are prosecuted for having the "wrong" religious beliefs there.