So, would a mirror coating on a missle be an effective counter measure to this laser?
That shouldn't be too difficult to do... heck, I was silvering mirrors in highschool chemistry class.
Well this laser is probably a COIL (chemical oxygen iodine laser), the military's favorite for laser weapons systems these days... COILs operate at a frequency of 1.315 micrometers... which is in the mid infrared band, for those that don't know... most mirrors (and substances) are opaque at this frequency; most of the light on this band is from blackbody radiation... here's an excellent primer on infrared transparency and absorbency...
You can make a dichroic mirror that reflects that wavelength, but the expense of coating a missle with it may be a couple orders of magnitude greater than the cost of the missle itself.
Here is a study of cutting different aerospace materials with a COIL. With a 6kW laser, they acheived a cut rate of.23 meters per minute through inch thick highly polished stainless steel.
So if you added a mirror to a missile, and this laser is 1MW with comparable focusing capabilities as that used in the above study, assume that it's pulse duration is somewhere in the neighborhood of a tenth of a second, and that the missile is covered with quarter-inch thick stainless steel (unlikely due to weight), and that you have to cut through 10 centimeters of the missile before you affect it's circuitry enough to guarantee non-operation, your mirror would have to be 96.5% efficient in order to work. Mirrors in the near infrared band are typically 80% - 90% efficient using exotic glass chemistries and aluminum front surfaces... this mirror in the mid infrared band would have to be significantly more efficient with far more difficult manufacturing techniques...
Let's see... 2.5 inch... less than 1cm tall... I've got a drive in my laptop that's 30 GB that size. 100GB is impressive, but is it really worth $1000? I mean if I've got portable storage requirements (video, maybe?) that big, I'd probably be better off with a USB 2.0 external... higher transfer rates and a third the cost...
Actually, the process I described is exactly what you are describing. Most 3D mesh programs have the ability to reduce a model to an arbitrary number of polygons; like JPEG compression, this feature turned up to high results in a blocky and angular image.
While I agree with you that most 3D data out there never had an original matrix, that doesn't change the fact that such a matrix would be analguous to uncompressed image or sound storage, and that the 3D formats we use are similar to lossy compressed versions of the same.
To give an example, I am a digital DJ. When I'm doing multitracking, my multitracker uses a high fidelity lossy compression algorithm; there is no point at which the sound data is represented digitally in a complete uncompressed manner. Simply because my first stage does not contain all the (mind numbingly insignificant) detail of the original, does not mean that this detail wasn't there...
If they come up with a convenient way of storing 3D information that is "lossy" but doesn't lose anything that will be missed, then more power to them.
Umm... we already do that.
Consider, a true 3D model would be a set of points and colors. The fineness of the points would be determined by the fineness of the capture device, all the way down to the atomic scale.
This is the equivalent of a bit-for-bit pixel-by-pixel BMP or WAV files.
But we don't represent 3D models that way... there's too much. So instead we take out all the interior data, data that could never be rendered if the model is non-transparent. Then we take points that are coplanar or nearly coplanar and make them into contiguous triangles that require far less geometry data to represent, and far less computational power to render. Then we take the surface data such as color, reflectivity, courseness, etc. and divorce it from the geometry, storing it in its own graphic files (usually JPEG or GIF)
This is analguous to the process of going through a WAV or BMP and finding features that are close enough to each other that we can remove details from them and those details will likely never be missed...
Anything which gives out lots of neutrons is going to have many of the problems of fission - any plant big enough tobe useful will need shielding and will produce nasty waste makeing decomissioning expensive.
They have yet to get a Tokamac to break even for more than a single run; the complexities are too much. They say that as they scale up this will be less and less of a problem...
As far as neutrons; the main problem isn't the waste material, it's transmutation of the reactor itself. They choose the elements used in building a tokamac very carefully to support the magnetic and physical forces. But in a few years of running, all those elements will be transmuted by neutron bombardment...
The problem being that bubble fusion depends on water. Basic physics here; Tin is the most stable element. Everything with an atomic level less than Tin is capable of fusing and releasing energy. Everything with an atomic level greater than Tin is capable of fissioning and releasing energy.
Titanium, tungsten, uranium, none of them would support fusion.
You know what the best element to fuse is? Hydrogen. The best isotope? Hydrogen-2. The liquid they are using? Deuterium ("heavy water"), which has one atom of Hydrogen-2, one of H, and one of O. And in the future they are looking at using Tritium, which is even heavier with 2 Hydrogen-2 atoms.
Yeah I thought about that... but it just didn't click. Why not have a generic email about anything anonymous email account. Having an email address for a particular story doesn't make sense... if it's a spam avoidance issue, why leave it unobfuscated on the front page of slashdot?
OK, you know that some guys private webspace on his dsl connected linux server is going to be slashdotted within seconds.
So why not actually put SOMETHING in the submission that describes, in some way, WHAT THE SITE IS ABOUT?
Ironically, "Anonymous Coward" who posted this story left as his e-mail address "hddassaultcannon@hotmail.com"... So even though the submission is in the third person, it was obviously written by the guy that did this.
I mean come on, he had to have some kind of idea what would happen, right?
Now, I'm not a rocketscientist, and I dont research fuelscells and batteries - but would it not been just as efficient, or even more efficient, to just store the electricity in a batterybank? Unlike in a car, weight and to a certain degree volume isn't a limiting factor in a house.
It's all about cost and energy density. The energy density in hydrogen is far greater than that of a similarly sized battery bank. And while a fuel cell is expensive, so are batteries. The difference being that this house can add extra energy storage just by installing an extra tank. To do that with batteries you've gotta buy a whole bunch more batteries.
That and batteries are cranky, require special circuitry, can vent harmful and corrosive substances (unignited hydrogen is neither harmful nor corrosive), and require replacing every 5-7 years in an application like this. And battery electrolyte can't directly power heaters, stoves, or air conditioners...
And I've played Crystal Chronicles; in Crystal Chronicles multiplayer, you use the GBA as your controller. Stats, items, spells, even radar are displayed directly on the GBA. When you first turn it on and between FMVs, it has a long please wait pause; I'm assuming it's transferring program code down the link. There is NO ROM in the GBA for this to occur. I wish they would reverse engineer this protocol.
Among other things, you could use your GBA for HUD in an FPS, create your own code without having to burn or print anything.
Couple that with the fact that Nintendo is re-releasing some of the e-Reader NES games on GBA cartridges this summer and I don't think they'll give a damn that someone reverse engineered code that anyone can see.
I'll be interested when someone releases a utility to directly translate and print NES ROMS... then I'll be a VERY happy man.
Hell, Nintendo could make some money at it just by offering a hardware device; you hook up an original NES ROM and the thermal printer prints a little sticker that you put on an e-Reader card blank...
Since we have no proof of anything beyond the Universe, this is just a chasing of a simple definition. Without the Universe in a 3D viewable environment and being just IT, then we can't define the shape meaningfully.
Contrarily, there are simple experiments we can do (and have done) to determine the shape of the universe. For instance, let's assume that you and I are two dimensional creatures living on the surface of a sphere. The sphere is very large, and you and I believe it to be infinite in all directions, and flat. We are in the profession of being surveyors, and we survey a few small triangles. A little known fact is that on the surface of a sphere all triangles have angles that add up to greater than 180 degrees; in fact if you measure a triangle that is proscribed orthogonally, it's angles are 270 degrees; to understand what I mean by orthogonal, I mean a triangle that has as its sides, if we were on the earth, the equator, the prime meridian, and 90 degrees longitude.
As we start measuring larger and larger triangles we find that our error increases more and more until we must assume that something is strange with the shape of our space; this is analguous to what our scientists have done. For more details, I highly recommend Sphereland...
Knowing the shape of the universe can be useful as we search for the Grand Unified Theory - the Theory that unifies gravity with the other fundamental forces, and reconciles macroscopic general relativity with microscopic quantum mechanics, and is therefore able to predict very precisely the outcome of any event at any scale.
By knowing the multi-dimensional topology of the universe, we can determine what the GUT may look like, and we can positively rule out GUT's that don't predict that the universe will have a specific topology that we have measured it to have.
please explain how a drive based on tiny fluctuations in a magnetic field can operate next to such a powerful magnet?
That's exactly it; the drive is based on fluctuations in the magnetic field. That's why things like vacuum cleaners are bad. However, permanent magnets, as long as they don't change position from the time that you write data to the time that you read it, are perfectly harmless; the field isn't changing, it's constant.
I wouldn't want to put a small permanent magent near it though. The falloff on a magnet is related to it's size; the smaller a magnet, the more rapid the falloff, which means the disc will see more variation as it spins...
This specification maintains the same usage and architecture as wired USB
Well unless they've been reading a ton of Tesla, I would call it the same usage or architecture as wired USB. Because USB is not only data but power, and AFAIK, wireless power distribution is neither a commodity technology nor tested to be safe in close quarters with humans...
The impact is that now I will have to turn devices on and off, worry about batteries, and power cords. Best case is everything gets (expensive) AAAs. Worst case is everything gets a power cord. If I'm using wireless USB, why would I want a power cord? I mean I'm not too keen on trading plugging in one thing for plugging in another.
And I've used wireless mice. They become erratic way before the batteries die. I like my HIDs to be precise and reliable, thank you very much...
If the laptop itself is still functional, you may want to consider a CF-2.5IDE converter, and burn a Live Linux distribution onto a compactflash card, and using VideoLan. Then you just have a server that is fundamentally a media controller, streaming video to the laptop...
This article is not advocating slowing down the security patch cycle; the slashdot title is misleading... the author is advocating slowing down the security patch distribution method.
He makes the point that as soon as a patch is available, it is reverse engineered and exploited. He is advocating sending out encrypted versions of a patch, get everyone who is always-connected to the internet to automatically download the encrypted version, and once the downloads per second curve decreases by a certain amount (say 95% or so), then you send out the decryption key. Everyone installs the patch simultaneously; and zero-day exploits have as targets only those systems that do not subscribe to the patch service, and use traditional methods to procure patches.
This is based on the assumption that zero-day exploits reverse engineer patches. I have found this not to be the case; they usually just exploit the vendor description of the vulnerability; in many cases, this description is posted to a security mailing list a few days (or weeks depending on the vendor) before a patch is available; usually this is the method by which a vendor finds a vulnerability.
This process is right and proper as it gives the vendor a huge incentive to correct flaws quickly; many people who discover a vulnerability report it to the vendor, wait for it to be fixed, and then when a fix is not apparent, report it to the community to give the vendor a sense of urgency. Unfortunately, it is a necessary part of the security patch cycle; without it, we would have a priviledged few individuals who could write truly devastating worms and virii, for which the vendor may not even be working on a patch.
SQL Slammer was bad. But imagine it if Microsoft had no intention of correcting the vulnerability at the time it hit. How many more people would it have hit, considering that a significant portion of Microsoft's customers had already patched at that point? How long would it take Microsoft to issue a patch? How would they distribute it with so much of the internet simply unavailable? How long until our infrastructure approached something like normalcy?
That's what could happen in a world where public forums don't hold vendors accountable for fixing vulnerabilities. And that's exactly the kind of world necessary for it to make sense to slow down your patch distribution.
Oh and BTW, Superconductors don't expel field lines exactly; they precisely resist all changes in magnetic fields; they are an infinite inductor. If a magnet is sitting on a superconductor when it goes critical, as the super conductor approaches critical it will become extremely diamagnetic, expelling field lines. When it goes critical, however, all field lines are trapped in place. This is where the standard magnet hovering over a superconductor spinning on its poles demo comes from; the poles are held in place by the trapped field lines.
Nature hates infinites, right? So how can a superconductor have infinite inductance? It does, up to a point. Once the magnetic flux through the superconductor reaches a certain level, depending on the particular type of superconductor, it either a) becomes non-superconducting due to peculiarities in the magnetic orientation of the superconducting components or b) the magnetic flux is greater than the material strength and it undergoes structural failure.
Just FYI, Bismuth and water are both diamagnetic; but their diamagnetic force is 10-13 orders of magnitude weaker than a standard lodestone...
And tonight I get my first up close and personal look at a really big superconductor. From the inside. I'd be excited if it weren't for the excruciating pain in my knee...
The best advice for anyone moving from Windows to a Linux GUI; mice with 3 buttons. A lot of the software such as gimp, blender, and audacity (used for 2-D images, 3-D images, and audio respectively) require a third button to function properly...
Finally -- and this is only because I'm tired of debunking this nonsense, not because he is done spouting it here -- materials don't "focus" magnetic fields as he describes. He makes it sounds like metals suck in field likes so that they pass through them. Field lines stay tied to whatever electically charged material they run through, but that's about it. You can superimpose fields, to be sure, but you can't just alter a field like without affecting the source.
Look up FEMM and play around with it a little... it shows that materials do indeed focus magnetic fields, and is generally accepted in the field as an accurate simulation tool. I just googled for the link: http://femm.foster-miller.com/
Also you might want to look at hall sensor designs; most of them involve using an iron nail or similar device in front of or behind the hall sensor, in order to focus the magnetic fields through the sensor.
As an experiment, take a soft iron cylinder, and put a strong magnet inside it. Don't let the magnet actually touch the walls of the cylinder, because that would magnetize the walls... wrap it with newspaper or something... screw the endcaps on... now if the field lines are passing through the metal, then you will be able to measure them from outside. However, if field lines tend to go through magnetically permeable materials, then they will go entirely through the cylinder and not be measurable from the outside.
It's called magnetic shielding, and it requires the very property you say doesn't exist.
Guess what? When I order magnets from forcefield.com, they ship in exactly that sort of container.
Actually, I used 72 letters (numbers 0-9 and 10 special characters... might be off a little, but should be good for ballpark).
72^8 = 722204136308736 No, I didn't add in the other possible lengths (speaking of which, you estimated 1 more combination than is possible with a 52 character set. 0-length passwords are not allowed)
The sample rate for CDs is absolutely fixed at 44.1 KHz as part of the spec. Now the rate that the CD producer uses for everything up to his digital master is completely up to him; for instance, in my all-digital recording studio, I sample at 96 KHz and then downsample when it comes time to burn a disc.
While it is true that the human mind is very well tuned to pick out speech in a low signal-to-noise ratio source, this may or may not be true of the ultrasonic range. Keep in mind that the ear is tuned by evolution to pick up and focus sounds that are audible; inaudible sounds are much more difficult for the physical mechanisms to pick up; in this case, high fidelity might help.
Slashdot Mirror
So, would a mirror coating on a missle be an effective counter measure to this laser?
.23 meters per minute through inch thick highly polished stainless steel.
That shouldn't be too difficult to do... heck, I was silvering mirrors in highschool chemistry class.
Well this laser is probably a COIL (chemical oxygen iodine laser), the military's favorite for laser weapons systems these days... COILs operate at a frequency of 1.315 micrometers... which is in the mid infrared band, for those that don't know... most mirrors (and substances) are opaque at this frequency; most of the light on this band is from blackbody radiation... here's an excellent primer on infrared transparency and absorbency...
You can make a dichroic mirror that reflects that wavelength, but the expense of coating a missle with it may be a couple orders of magnitude greater than the cost of the missle itself.
Here is a study of cutting different aerospace materials with a COIL. With a 6kW laser, they acheived a cut rate of
So if you added a mirror to a missile, and this laser is 1MW with comparable focusing capabilities as that used in the above study, assume that it's pulse duration is somewhere in the neighborhood of a tenth of a second, and that the missile is covered with quarter-inch thick stainless steel (unlikely due to weight), and that you have to cut through 10 centimeters of the missile before you affect it's circuitry enough to guarantee non-operation, your mirror would have to be 96.5% efficient in order to work. Mirrors in the near infrared band are typically 80% - 90% efficient using exotic glass chemistries and aluminum front surfaces... this mirror in the mid infrared band would have to be significantly more efficient with far more difficult manufacturing techniques...
Let's see... 2.5 inch... less than 1cm tall... I've got a drive in my laptop that's 30 GB that size. 100GB is impressive, but is it really worth $1000? I mean if I've got portable storage requirements (video, maybe?) that big, I'd probably be better off with a USB 2.0 external... higher transfer rates and a third the cost...
Actually, the process I described is exactly what you are describing. Most 3D mesh programs have the ability to reduce a model to an arbitrary number of polygons; like JPEG compression, this feature turned up to high results in a blocky and angular image.
While I agree with you that most 3D data out there never had an original matrix, that doesn't change the fact that such a matrix would be analguous to uncompressed image or sound storage, and that the 3D formats we use are similar to lossy compressed versions of the same.
To give an example, I am a digital DJ. When I'm doing multitracking, my multitracker uses a high fidelity lossy compression algorithm; there is no point at which the sound data is represented digitally in a complete uncompressed manner. Simply because my first stage does not contain all the (mind numbingly insignificant) detail of the original, does not mean that this detail wasn't there...
If they come up with a convenient way of storing 3D information that is "lossy" but doesn't lose anything that will be missed, then more power to them.
Umm... we already do that.
Consider, a true 3D model would be a set of points and colors. The fineness of the points would be determined by the fineness of the capture device, all the way down to the atomic scale.
This is the equivalent of a bit-for-bit pixel-by-pixel BMP or WAV files.
But we don't represent 3D models that way... there's too much. So instead we take out all the interior data, data that could never be rendered if the model is non-transparent. Then we take points that are coplanar or nearly coplanar and make them into contiguous triangles that require far less geometry data to represent, and far less computational power to render. Then we take the surface data such as color, reflectivity, courseness, etc. and divorce it from the geometry, storing it in its own graphic files (usually JPEG or GIF)
This is analguous to the process of going through a WAV or BMP and finding features that are close enough to each other that we can remove details from them and those details will likely never be missed...
Anything which gives out lots of neutrons is going to have many of the problems of fission - any plant big enough tobe useful will need shielding and will produce nasty waste makeing decomissioning expensive.
They have yet to get a Tokamac to break even for more than a single run; the complexities are too much. They say that as they scale up this will be less and less of a problem...
As far as neutrons; the main problem isn't the waste material, it's transmutation of the reactor itself. They choose the elements used in building a tokamac very carefully to support the magnetic and physical forces. But in a few years of running, all those elements will be transmuted by neutron bombardment...
Or they might try a liquid other than water
The problem being that bubble fusion depends on water. Basic physics here; Tin is the most stable element. Everything with an atomic level less than Tin is capable of fusing and releasing energy. Everything with an atomic level greater than Tin is capable of fissioning and releasing energy.
Titanium, tungsten, uranium, none of them would support fusion.
You know what the best element to fuse is? Hydrogen. The best isotope? Hydrogen-2. The liquid they are using? Deuterium ("heavy water"), which has one atom of Hydrogen-2, one of H, and one of O. And in the future they are looking at using Tritium, which is even heavier with 2 Hydrogen-2 atoms.
Yeah I thought about that... but it just didn't click. Why not have a generic email about anything anonymous email account. Having an email address for a particular story doesn't make sense... if it's a spam avoidance issue, why leave it unobfuscated on the front page of slashdot?
OK, you know that some guys private webspace on his dsl connected linux server is going to be slashdotted within seconds.
So why not actually put SOMETHING in the submission that describes, in some way, WHAT THE SITE IS ABOUT?
Ironically, "Anonymous Coward" who posted this story left as his e-mail address "hddassaultcannon@hotmail.com"... So even though the submission is in the third person, it was obviously written by the guy that did this.
I mean come on, he had to have some kind of idea what would happen, right?
Now, I'm not a rocketscientist, and I dont research fuelscells and batteries - but would it not been just as efficient, or even more efficient, to just store the electricity in a batterybank? Unlike in a car, weight and to a certain degree volume isn't a limiting factor in a house.
It's all about cost and energy density. The energy density in hydrogen is far greater than that of a similarly sized battery bank. And while a fuel cell is expensive, so are batteries. The difference being that this house can add extra energy storage just by installing an extra tank. To do that with batteries you've gotta buy a whole bunch more batteries.
That and batteries are cranky, require special circuitry, can vent harmful and corrosive substances (unignited hydrogen is neither harmful nor corrosive), and require replacing every 5-7 years in an application like this. And battery electrolyte can't directly power heaters, stoves, or air conditioners...
I've seen USB to GBA cables.
And I've played Crystal Chronicles; in Crystal Chronicles multiplayer, you use the GBA as your controller. Stats, items, spells, even radar are displayed directly on the GBA. When you first turn it on and between FMVs, it has a long please wait pause; I'm assuming it's transferring program code down the link. There is NO ROM in the GBA for this to occur. I wish they would reverse engineer this protocol.
Among other things, you could use your GBA for HUD in an FPS, create your own code without having to burn or print anything.
Geek heaven.
Of course, personally, I just built my own development environment by downloading and building my compiler and related tools by hand.
Got some linkage to a howto?
Couple that with the fact that Nintendo is re-releasing some of the e-Reader NES games on GBA cartridges this summer and I don't think they'll give a damn that someone reverse engineered code that anyone can see.
I'll be interested when someone releases a utility to directly translate and print NES ROMS... then I'll be a VERY happy man.
Hell, Nintendo could make some money at it just by offering a hardware device; you hook up an original NES ROM and the thermal printer prints a little sticker that you put on an e-Reader card blank...
By The Gathering I'm assuming you don't mean "The Gathering of the Juggalos"... what other The Gathering do you mean?
Since we have no proof of anything beyond the Universe, this is just a chasing of a simple definition. Without the Universe in a 3D viewable environment and being just IT, then we can't define the shape meaningfully.
Contrarily, there are simple experiments we can do (and have done) to determine the shape of the universe. For instance, let's assume that you and I are two dimensional creatures living on the surface of a sphere. The sphere is very large, and you and I believe it to be infinite in all directions, and flat. We are in the profession of being surveyors, and we survey a few small triangles. A little known fact is that on the surface of a sphere all triangles have angles that add up to greater than 180 degrees; in fact if you measure a triangle that is proscribed orthogonally, it's angles are 270 degrees; to understand what I mean by orthogonal, I mean a triangle that has as its sides, if we were on the earth, the equator, the prime meridian, and 90 degrees longitude.
As we start measuring larger and larger triangles we find that our error increases more and more until we must assume that something is strange with the shape of our space; this is analguous to what our scientists have done. For more details, I highly recommend Sphereland...
Knowing the shape of the universe can be useful as we search for the Grand Unified Theory - the Theory that unifies gravity with the other fundamental forces, and reconciles macroscopic general relativity with microscopic quantum mechanics, and is therefore able to predict very precisely the outcome of any event at any scale.
By knowing the multi-dimensional topology of the universe, we can determine what the GUT may look like, and we can positively rule out GUT's that don't predict that the universe will have a specific topology that we have measured it to have.
please explain how a drive based on tiny fluctuations in a magnetic field can operate next to such a powerful magnet?
That's exactly it; the drive is based on fluctuations in the magnetic field. That's why things like vacuum cleaners are bad. However, permanent magnets, as long as they don't change position from the time that you write data to the time that you read it, are perfectly harmless; the field isn't changing, it's constant.
I wouldn't want to put a small permanent magent near it though. The falloff on a magnet is related to it's size; the smaller a magnet, the more rapid the falloff, which means the disc will see more variation as it spins...
This specification maintains the same usage and architecture as wired USB
Well unless they've been reading a ton of Tesla, I would call it the same usage or architecture as wired USB. Because USB is not only data but power, and AFAIK, wireless power distribution is neither a commodity technology nor tested to be safe in close quarters with humans...
The impact is that now I will have to turn devices on and off, worry about batteries, and power cords. Best case is everything gets (expensive) AAAs. Worst case is everything gets a power cord. If I'm using wireless USB, why would I want a power cord? I mean I'm not too keen on trading plugging in one thing for plugging in another.
And I've used wireless mice. They become erratic way before the batteries die. I like my HIDs to be precise and reliable, thank you very much...
If the laptop itself is still functional, you may want to consider a CF-2.5IDE converter, and burn a Live Linux distribution onto a compactflash card, and using VideoLan. Then you just have a server that is fundamentally a media controller, streaming video to the laptop...
Because fitting a 2.5in disk inside a 1cm cartridge has to involve some sort of space folding technology...
I'm assuming the poster misplaced some decimal points on the cartridge size...
This article is not advocating slowing down the security patch cycle; the slashdot title is misleading... the author is advocating slowing down the security patch distribution method.
He makes the point that as soon as a patch is available, it is reverse engineered and exploited. He is advocating sending out encrypted versions of a patch, get everyone who is always-connected to the internet to automatically download the encrypted version, and once the downloads per second curve decreases by a certain amount (say 95% or so), then you send out the decryption key. Everyone installs the patch simultaneously; and zero-day exploits have as targets only those systems that do not subscribe to the patch service, and use traditional methods to procure patches.
This is based on the assumption that zero-day exploits reverse engineer patches. I have found this not to be the case; they usually just exploit the vendor description of the vulnerability; in many cases, this description is posted to a security mailing list a few days (or weeks depending on the vendor) before a patch is available; usually this is the method by which a vendor finds a vulnerability.
This process is right and proper as it gives the vendor a huge incentive to correct flaws quickly; many people who discover a vulnerability report it to the vendor, wait for it to be fixed, and then when a fix is not apparent, report it to the community to give the vendor a sense of urgency. Unfortunately, it is a necessary part of the security patch cycle; without it, we would have a priviledged few individuals who could write truly devastating worms and virii, for which the vendor may not even be working on a patch.
SQL Slammer was bad. But imagine it if Microsoft had no intention of correcting the vulnerability at the time it hit. How many more people would it have hit, considering that a significant portion of Microsoft's customers had already patched at that point? How long would it take Microsoft to issue a patch? How would they distribute it with so much of the internet simply unavailable? How long until our infrastructure approached something like normalcy?
That's what could happen in a world where public forums don't hold vendors accountable for fixing vulnerabilities. And that's exactly the kind of world necessary for it to make sense to slow down your patch distribution.
Sorry I obviously didn't RTFA.
Oh and BTW, Superconductors don't expel field lines exactly; they precisely resist all changes in magnetic fields; they are an infinite inductor. If a magnet is sitting on a superconductor when it goes critical, as the super conductor approaches critical it will become extremely diamagnetic, expelling field lines. When it goes critical, however, all field lines are trapped in place. This is where the standard magnet hovering over a superconductor spinning on its poles demo comes from; the poles are held in place by the trapped field lines.
Nature hates infinites, right? So how can a superconductor have infinite inductance? It does, up to a point. Once the magnetic flux through the superconductor reaches a certain level, depending on the particular type of superconductor, it either a) becomes non-superconducting due to peculiarities in the magnetic orientation of the superconducting components or b) the magnetic flux is greater than the material strength and it undergoes structural failure.
Just FYI, Bismuth and water are both diamagnetic; but their diamagnetic force is 10-13 orders of magnitude weaker than a standard lodestone...
And tonight I get my first up close and personal look at a really big superconductor. From the inside. I'd be excited if it weren't for the excruciating pain in my knee...
The best advice for anyone moving from Windows to a Linux GUI; mice with 3 buttons. A lot of the software such as gimp, blender, and audacity (used for 2-D images, 3-D images, and audio respectively) require a third button to function properly...
Finally -- and this is only because I'm tired of debunking this nonsense, not because he is done spouting it here -- materials don't "focus" magnetic fields as he describes. He makes it sounds like metals suck in field likes so that they pass through them. Field lines stay tied to whatever electically charged material they run through, but that's about it. You can superimpose fields, to be sure, but you can't just alter a field like without affecting the source.
Look up FEMM and play around with it a little... it shows that materials do indeed focus magnetic fields, and is generally accepted in the field as an accurate simulation tool. I just googled for the link: http://femm.foster-miller.com/
Also you might want to look at hall sensor designs; most of them involve using an iron nail or similar device in front of or behind the hall sensor, in order to focus the magnetic fields through the sensor.
As an experiment, take a soft iron cylinder, and put a strong magnet inside it. Don't let the magnet actually touch the walls of the cylinder, because that would magnetize the walls... wrap it with newspaper or something... screw the endcaps on... now if the field lines are passing through the metal, then you will be able to measure them from outside. However, if field lines tend to go through magnetically permeable materials, then they will go entirely through the cylinder and not be measurable from the outside.
It's called magnetic shielding, and it requires the very property you say doesn't exist.
Guess what? When I order magnets from forcefield.com, they ship in exactly that sort of container.
Eh... .NET is natively compiled when it's run for the first time. It also optimizes for the platform (even CPU) it runs on.
Actually, most programs native compile it during the install. Only if the assembly is not natively compiled does it get so on load time...
Actually, I used 72 letters (numbers 0-9 and 10 special characters... might be off a little, but should be good for ballpark).
72^8 = 722204136308736 No, I didn't add in the other possible lengths (speaking of which, you estimated 1 more combination than is possible with a 52 character set. 0-length passwords are not allowed)
722204136308736 attempts / (45000000 attempts / second) / (86400 seconds / day) = 185 days
The sample rate for CDs is absolutely fixed at 44.1 KHz as part of the spec. Now the rate that the CD producer uses for everything up to his digital master is completely up to him; for instance, in my all-digital recording studio, I sample at 96 KHz and then downsample when it comes time to burn a disc.
While it is true that the human mind is very well tuned to pick out speech in a low signal-to-noise ratio source, this may or may not be true of the ultrasonic range. Keep in mind that the ear is tuned by evolution to pick up and focus sounds that are audible; inaudible sounds are much more difficult for the physical mechanisms to pick up; in this case, high fidelity might help.