"Cold" fusion is when the nuclei fuse at "low" temperature. Not just the outside of the reactor that is cold, but the actual nuclei that fuse are "cold". When you're talking about the temperature of atoms, or nuclei, the temperature is the same as energy. This reactor accelerates the ions to high energy, so it's not "cold fusion".
The original "cold fusion" apparatus (the one that didn't work, or at least no one was ever able to replicate the experiment) used an electrolytic cell with palladium electrodes in an electrolyte. Nowhere in the apparatus were the deuterium nuclei accelerated to high speed. The theory was that the current somehow induces the deuterium to infuse into the palladium electrode, where the deuterium nuclei get close enough to each other to fuse, without you having to clash them together at high energy.
That was the cool thing about it (pardon the pun). You didn't have to put much energy into the system, so you had more energy coming out than you had to put in, making it a feasable power source. If it worked:-).
It took me a while to realize what the heck neutron sources might have to do with homeland security. I think what they have in mind is detection of fissile material (i.e. uranium and plutonium, as in nukes).
You irradiate the baggage/cargo (or whatever) with neutrons, and check the outgoing neutron flux with a geigerzahler or some other neutron detector. If there is fissile material in the baggage, some of it would split, generating detectably more neutrons.
If you want to get cute about it, note that fission neutrons have lower energy than fusion neutrons. Then use a neutron detector that can differentiate neutrons by energy.
Now, you can probably detect neutron flux from spontaneous fission without any irradiation, but depending on type of fissile material and amount of shielding that flux might be too low to detect reliably. And you wouldn't be able to tell an isotopic neutron source from fissile materials. Not that isotopic neutron sources shouldn't raise suspicion if found in cargo/baggage.
The only real problem with a detector based on neutron irradiation is that you have to keep people the hell away from it:-).
Secondly, they haven't discovered fusion, they have invented a new type of fusion-based neutron generator. Several types of neutron generators are commonly known, and some are simple enough that you could build a working one in your garage. All of them use the same principle, more or less - high voltage, on the order of 100kV, accelerates deuterium ions into a deuterium (or tritium) containing target. So does this one.
The novelty is that they used a pyroelectric crystal to generate the high voltage. This makes the device small and self-contained, with no need for high-voltage electric machinery. All you do is heat-cycle the crystal with some 50 degree C temperature span, and you get fusion neutrons.
Note that like all fusion devices to date (other than bombs), this gadget produces a lot less fusion energy than is put in, and brings us no closer to having a fusion-based power source.
But it's a neat idea. And it makes a neat cheap laboratory neutron source.
Holy Crap, no matter how much of a nerd you are you realize there are always bigger ones. Dude ions and erbin-somethin's collide and holy cow they make 900 other-sumpthins that's like 400 times the back-doo-dad!
That whole article could have been written in Esperanto for as much as I could get from it and I have a solid background in Compsci, EE, and sci.
In other words, you're amazed that you're such a dumbass, despite your solid background, and you are proud of it at the same time:-). Man, you need a beer!
Pulse neutron tubes are fusion-based neutron sources, most commonly used in circa 1970 atom bomb trigger mechanisms. They are also used for peaceful purposes, pretty much whenever one needs a 14 MeV neutron source. The vacuum tube uses very high voltage to accelerate deterium ions towards a target. Or something... In other words, achieving fusion at room temperature in a small apparatus is no big deal. The problem is that you always have to input way more energy into the device than you can get out. I don't see how any of these new advances in achieving fusion bring us closer to use of fusion as power source. Not to say that this new fusion neutron source is a wonderful scientific achievment, it is, it's just doesn't seem likely to be a potential power source technology.
From what I remember, properly implemented command mode escape required a "guard time" before and after the +++. The guard time could have been about a second, and you could set it via a register on some modems. According to the initial design, the +++ had to be sent back-to-back, without any delay in between, but that requirement was rarely implemented since it wouldn't be possible to type +++ back-to-back, and the sequence would always have to be scripted, which is inconvinient.
Of course, the +++ escape should obviously only ever work on the sent data, so the NO CARRIER hack could only work with ridiculously stupid modem firmware.
There is simply nothing else that can power a long range mission. Bad as it is, fission power is really the only choice.
1. The mass of reactor is lot higher.
The energy density of that reactor is also a lot higher.
2. The nuclear(fission) reaction is not clean. The radiation (yes no shielding is enough) can be hazardous to equipment
You bet! It's about as bad as it gets. Radiation hardening of equipment is an old science, though, from the 60s. Modern integrated electronics are more delicate than the '60s transistor-based stuff, but still, radiation levels are not a show-stopper. Besides, no matter what you use for propulsion, you have to deal with cosmic rays anyways.
3. There are safety hazards for manned missions.
With a nuke you can go faster, reducing the exposure to cosmic rays, thus balancing out the radiation from the reactor.
4. Failed launches will spread debris of nuclear waste all over the earth.
What if you launch with a cold reactor, and only bring it online in orbit? Then the only radioactive material in the reactor at time of launch would be the fuel itself, i.e. only a few kilos of plutonium, inside a hardened shell that would survive reentry if the launch fails. This could be made safe enough - even safer than running a reactor on Earth.
5. Operation/automation of nuclear reactor is much more complex task than operating the spacecraft itself.
Just send Homer Simpson:-).
Seriously, Do you think the reactors on the submarines are manually controlled? Of course, on an unmanned mission there are no humans around to service it if it fails, but that's a problem with any space equipment.
Fusion technology has a long way to go before it becomes operational in space.
Fusion technology (short of bombs and stars) has a long way to go before it becomes operational. Period. This is one good reason to use a fission nuke. BTW, fusion, even cold fusion, would still create neutron radiation, so all the problems with the shielding remain.
The blurb is talking about protons that need to be reduced to make hydrogen, so it's only natural to assume that the input electricity all goes into reducing the protons to hydrogen, at one electron per hydrogen atom.
What, lousy fucks put all their customer data on one backup tape, and it's not their fault when the tape gets lost?
Hell, of course it's not their fault that the tape got lost
But it is their fault that the data got lost when that one tape got lost. Don't they, like, have anyone in the company who knows the meaning of the word backup?
They probably want to cash in on people buying second-hand hardware. Thing is, if you're buying second-hand hardware, you'd more than likely try and save on the drivers by getting a copy off of somewhere, especially that after buying the hardware you're entitled to the drivers anyways.
They probably also want to cash in on people who loose their driver discs. Which is a really smooth move, one way to make sure that the guy's next camera won't be a Nikon, and the guy's friends' next cameras won't be Nikons. DSLR cameras are one field where vendor lock-in works wonders, what with all the lenses and speelights that you invest in that won't fit the competition's cameras. You have to really work your customers to make them switch over to competition.
He says his files "deteriorate" on the disk, i.e. the computer doesn't hang, he doesn't get disk error messages, but the same file reads differently, with more and more errors every time. Since there is ECC on the drive, it's hardly possible for disk errors to go undetected. Something outside of the drive is garbling the files.
Since the file is already on the drive, a hardware problem (a flakey IDE cable, or a memory bit error) could cause the file to read differently every time, but it would not "deteriorate" with every read. So it must be that some software is writing over your files in between the reads. There have been virus payloads that would flip random bits in files like that. Or, you could have a corrupt filesystem.
Let's just concede they can actually produce a junk file which has the same hash.
KAZAA uses weak hash that only hashes small parts of the file. Just search wikipedia for UUHash for details. Given that, injecting bad data into KAZAA is trivial, and not even worth a patent. All other P2P networks use secure hash algorithms, and are not vulnerable to this nonsense anyways.
Even if the files differ in exactly 1 bit -- the hash would be unrecognizably different. That follows directly from the definition of cryptographically-strong hash.
Private network means registered IPs, and secret keys, which makes it very difficult to hack from the outside. If you run BitTorrent, but only give the.torrent to your friends, you are safe, as long as none of your friends is a narc^H^H^H^HRIAA agent.
"used McDonald's fry vat grease" becomes biodiesel with some processing. Almost any old diesel engine can run on biodiesel. Nothing alternative about it, except that it's still more expensive than diesel, and the exhaust smells like McD's (yucK!).
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I think it was sodium cooled, and a sodium explosion was both part of the disaster, and the "disassembly method".
They use liquid sodium metal in nuclear reactors. you do NOT want this in your computer.
I dunno 'bout computers... I know I definitely don't want this in my toilet.
Is it true that sodium has been used as coolant in the piston engines of circa-WWII aeroplanes? I heard some stories...
But the truth is, 99% of gun use is against people.
C'mon, 99% of gun use is for target practice.
All you have to do is invent a new keyboard!
"Cold" fusion is when the nuclei fuse at "low" temperature. Not just the outside of the reactor that is cold, but the actual nuclei that fuse are "cold". When you're talking about the temperature of atoms, or nuclei, the temperature is the same as energy. This reactor accelerates the ions to high energy, so it's not "cold fusion".
The original "cold fusion" apparatus (the one that didn't work, or at least no one was ever able to replicate the experiment) used an electrolytic cell with palladium electrodes in an electrolyte. Nowhere in the apparatus were the deuterium nuclei accelerated to high speed. The theory was that the current somehow induces the deuterium to infuse into the palladium electrode, where the deuterium nuclei get close enough to each other to fuse, without you having to clash them together at high energy.
That was the cool thing about it (pardon the pun). You didn't have to put much energy into the system, so you had more energy coming out than you had to put in, making it a feasable power source. If it worked:-).
It took me a while to realize what the heck neutron sources might have to do with homeland security. I think what they have in mind is detection of fissile material (i.e. uranium and plutonium, as in nukes).
You irradiate the baggage/cargo (or whatever) with neutrons, and check the outgoing neutron flux with a geigerzahler or some other neutron detector. If there is fissile material in the baggage, some of it would split, generating detectably more neutrons.
If you want to get cute about it, note that fission neutrons have lower energy than fusion neutrons. Then use a neutron detector that can differentiate neutrons by energy.
Now, you can probably detect neutron flux from spontaneous fission without any irradiation, but depending on type of fissile material and amount of shielding that flux might be too low to detect reliably. And you wouldn't be able to tell an isotopic neutron source from fissile materials. Not that isotopic neutron sources shouldn't raise suspicion if found in cargo/baggage.
The only real problem with a detector based on neutron irradiation is that you have to keep people the hell away from it:-).
First of all, this is a dupe
Secondly, they haven't discovered fusion, they have invented a new type of fusion-based neutron generator. Several types of neutron generators are commonly known, and some are simple enough that you could build a working one in your garage. All of them use the same principle, more or less - high voltage, on the order of 100kV, accelerates deuterium ions into a deuterium (or tritium) containing target. So does this one.
The novelty is that they used a pyroelectric crystal to generate the high voltage. This makes the device small and self-contained, with no need for high-voltage electric machinery. All you do is heat-cycle the crystal with some 50 degree C temperature span, and you get fusion neutrons.
Note that like all fusion devices to date (other than bombs), this gadget produces a lot less fusion energy than is put in, and brings us no closer to having a fusion-based power source.
But it's a neat idea. And it makes a neat cheap laboratory neutron source.
Holy Crap, no matter how much of a nerd you are you realize there are always bigger ones. Dude ions and erbin-somethin's collide and holy cow they make 900 other-sumpthins that's like 400 times the back-doo-dad!
That whole article could have been written in Esperanto for as much as I could get from it and I have a solid background in Compsci, EE, and sci.
In other words, you're amazed that you're such a dumbass, despite your solid background, and you are proud of it at the same time:-). Man, you need a beer!
Don't forget the good old pulse neutron tubes.
Pulse neutron tubes are fusion-based neutron sources, most commonly used in circa 1970 atom bomb trigger mechanisms. They are also used for peaceful purposes, pretty much whenever one needs a 14 MeV neutron source. The vacuum tube uses very high voltage to accelerate deterium ions towards a target. Or something... In other words, achieving fusion at room temperature in a small apparatus is no big deal. The problem is that you always have to input way more energy into the device than you can get out. I don't see how any of these new advances in achieving fusion bring us closer to use of fusion as power source. Not to say that this new fusion neutron source is a wonderful scientific achievment, it is, it's just doesn't seem likely to be a potential power source technology.
From what I remember, properly implemented command mode escape required a "guard time" before and after the +++. The guard time could have been about a second, and you could set it via a register on some modems. According to the initial design, the +++ had to be sent back-to-back, without any delay in between, but that requirement was rarely implemented since it wouldn't be possible to type +++ back-to-back, and the sequence would always have to be scripted, which is inconvinient.
Of course, the +++ escape should obviously only ever work on the sent data, so the NO CARRIER hack could only work with ridiculously stupid modem firmware.
There is simply nothing else that can power a long range mission. Bad as it is, fission power is really the only choice.
1. The mass of reactor is lot higher.
The energy density of that reactor is also a lot higher.
2. The nuclear(fission) reaction is not clean. The radiation (yes no shielding is enough) can be hazardous to equipment
You bet! It's about as bad as it gets. Radiation hardening of equipment is an old science, though, from the 60s. Modern integrated electronics are more delicate than the '60s transistor-based stuff, but still, radiation levels are not a show-stopper. Besides, no matter what you use for propulsion, you have to deal with cosmic rays anyways.
3. There are safety hazards for manned missions.
With a nuke you can go faster, reducing the exposure to cosmic rays, thus balancing out the radiation from the reactor.
4. Failed launches will spread debris of nuclear waste all over the earth.
What if you launch with a cold reactor, and only bring it online in orbit? Then the only radioactive material in the reactor at time of launch would be the fuel itself, i.e. only a few kilos of plutonium, inside a hardened shell that would survive reentry if the launch fails. This could be made safe enough - even safer than running a reactor on Earth.
5. Operation/automation of nuclear reactor is much more complex task than operating the spacecraft itself.
Just send Homer Simpson:-).
Seriously, Do you think the reactors on the submarines are manually controlled? Of course, on an unmanned mission there are no humans around to service it if it fails, but that's a problem with any space equipment.
Fusion technology has a long way to go before it becomes operational in space.
Fusion technology (short of bombs and stars) has a long way to go before it becomes operational. Period. This is one good reason to use a fission nuke. BTW, fusion, even cold fusion, would still create neutron radiation, so all the problems with the shielding remain.
The blurb is talking about protons that need to be reduced to make hydrogen, so it's only natural to assume that the input electricity all goes into reducing the protons to hydrogen, at one electron per hydrogen atom.
What, lousy fucks put all their customer data on one backup tape, and it's not their fault when the tape gets lost?
Hell, of course it's not their fault that the tape got lost
But it is their fault that the data got lost when that one tape got lost. Don't they, like, have anyone in the company who knows the meaning of the word backup?
They probably want to cash in on people buying second-hand hardware. Thing is, if you're buying second-hand hardware, you'd more than likely try and save on the drivers by getting a copy off of somewhere, especially that after buying the hardware you're entitled to the drivers anyways.
They probably also want to cash in on people who loose their driver discs. Which is a really smooth move, one way to make sure that the guy's next camera won't be a Nikon, and the guy's friends' next cameras won't be Nikons. DSLR cameras are one field where vendor lock-in works wonders, what with all the lenses and speelights that you invest in that won't fit the competition's cameras. You have to really work your customers to make them switch over to competition.
When you play with the devil... you will get burned.
And if you play with matches... you will go to hell??
You'd be sharing airspace with him:-). And, going 55, you'd be constantly passed by flying semis, honking at you and lighting you up with highbeams.
He says his files "deteriorate" on the disk, i.e. the computer doesn't hang, he doesn't get disk error messages, but the same file reads differently, with more and more errors every time. Since there is ECC on the drive, it's hardly possible for disk errors to go undetected. Something outside of the drive is garbling the files.
Since the file is already on the drive, a hardware problem (a flakey IDE cable, or a memory bit error) could cause the file to read differently every time, but it would not "deteriorate" with every read. So it must be that some software is writing over your files in between the reads. There have been virus payloads that would flip random bits in files like that. Or, you could have a corrupt filesystem.
...the validity of the file can only be checked once the file has been fully downloaded.
Two words:
Tiger-Tree Hash.
Let's just concede they can actually produce a junk file which has the same hash.
KAZAA uses weak hash that only hashes small parts of the file. Just search wikipedia for UUHash for details. Given that, injecting bad data into KAZAA is trivial, and not even worth a patent. All other P2P networks use secure hash algorithms, and are not vulnerable to this nonsense anyways.
Even if the files differ in exactly 1 bit -- the hash would be unrecognizably different. That follows directly from the definition of cryptographically-strong hash.
Private network means registered IPs, and secret keys, which makes it very difficult to hack from the outside. If you run BitTorrent, but only give the .torrent to your friends, you are safe, as long as none of your friends is a narc^H^H^H^HRIAA agent.
Hard drive failure results in "Disk error" messages; not EVER do bits in a file on a modern hard drive just flip on their own without a warning.
Filesystem failures are a different story. Run checkdisk.
"used McDonald's fry vat grease" becomes biodiesel with some processing. Almost any old diesel engine can run on biodiesel. Nothing alternative about it, except that it's still more expensive than diesel, and the exhaust smells like McD's (yucK!).