Anyone who's done any kind of IOS upgrading on some of the upper-end Cisco routers and Juniper routers knows that the upgraded images aren't always the most stable items around.
So try Redback's Smartedge. It uses a separately-developed code base.
Well, he wrote "Do Androids dream of Electric Sheep", which Blade Runner was based on. Happy now?
Nope.
Blade Runner wasn't based on "Do Androids Dream of Electric Sheep?" The MOVIE CALLED "Blade Runner" was based on ""Do Androids Dream of Electric Sheep?"
This is not a silly quibble. Blade Runner was a completely different book (By Alan E. Nourse, if I recall correctly). It's about a future dystopia where medical care is banned (in a misguided attempt to breed out dangerous recessives), except for people who have been sterilized. A very fatal Flu is circulating. There's a vaccine, but because you can't get it unless you volunteer for sterilization you're about to have a situation where all the surviving humans are sterile. One lead character is a "Blade Runner" - a surgical tool bootlegger for an illegal surgeon.
The makers of the movie version of "Do Androids dream of Electric Sheep" blatantly ripped off the name of the unrelated book - apparently because it sounded cool. Nothing in the movie is in any way related to blades or the book with the same title.
So the media empire strikes again, shafting TWO authors for the price of one.
You are basing your argument on an invalid assumption: That all 5% of Mac users would get this service, if it were made available. This is totally false.
No, I'm not assuming that. In the sole-provider case I'm assuming you get the same percentage of adopters among Mac (or whatever) users as you got among Windoze users.
In the multiple provider case I'm assuming that you end up with the same fraction of Mac users adopting the TYPE OF SERVICE/DEVICE as Windows users.
For instance - if the product is satellite networking I'm assuming the same fraction of Mac users as Windows users would buy it - IF the Mac users could get it at all.
How many times can we go over this same point? It's the same for Linux and Mac, it's just not economically viable to develop software for something used by less than 5% of the computing masses.
Let's phrase this another way:
How much would a company pay for ADVERTISING to get a 5% increase in sales? (And thus a MUCH greater than 5% improvement in profits, since the development is already amortized.)
Now if that same amount bought you the development of an incremental feature (i.e. a Linux or Mac driver) that enables another 5% of the market to use your product, it's the same case. (Actually, if you're currently addressing 90% of the potential market and the new segment is an incremental 5% you're adding 5%/90% or about 5.6%).
But wait, it's better...
Suppose that you're currently splitting the market evenly with one other competitor. If YOU do it and HE doesn't, that 5.55% about doubles to 11.1%. With an even split among three competitors the first mover gets about a 16.7% bump in potential sales (and more in profit), and so on.
With something like networking you have a small number of competitors but MAJOR lock-in. First mover gets the prize and KEEPS it. With something (like a device) with more competitors and less lock-in you may not keep it, but you get a BIG boost until your competition wises up.
But WAIT! You don't HAVE to develop it yourself! Publish enough of the interoperability specs and - at least for Linux - SOMEONE ELSE will do it FOR you! You get the benefits and do only a tiny fraction of the work.
Your work consists mostly editing your internal documents into an externally-releasable one that will enable a developer without giving away your trade-secret farm. But don't get too paranoid: Your competitors are ALREADY reverse-engineering you. You should have your critrical IP already locked up in patent-pending, which will keep your competition at bay if you publish more than you intended. Meanwhile, better specs mean better and sooner community software to enable your sales.
Network operators might have some issues with security - but that's already been addressed elsewhere. (Bottom line is that the black hats will get you anyhow if you're already BADLY broken, regardless of whether you publish, while if you're reasonably secure (i.e. only a little flakey) the exposure will get the white hats on your side and you'll probably increase your lead in the arms race.)
Every time someone calls with a question, it costs the company money. The quicker you can answer their question and get them off the phone, the better. This means minimizing the number of different systems your support folks have to be trained for.
So have the bulk of them trained for the bulk operating system, a few trained for each little one, and TRANSFER THE CALL if you get one for a little opsys. We are talking NETWORK companies, right?
Heck - I bet the little guys would put up with a half-day delay and callback - and be grateful they could buy your stuff at all. YOU get to schedule the calls, rather than fielding them when they arrive - increasing the efficiency of the little-opsys helpers.
Yeah, but water is heavy and would run out and need to be refilled.
So does the fuel for the laser - or the engines. It's just another tank (and a small one) to be filled. (If the laser is chemically-pumped you could include the cooling water in the fuel canister and reload just like you would a machine gun or missile pod.)
Aerospace engineers _hate_ weight more than anything (including enemy aerospace engineers).
Ablative cooling - in the form of boiling water - has one of the highest cooling-to-weight ratios of any cooling system.
Vent the steam. The F-35 is suppose to be stealthy. Leaving a con trail of vented steam does not help the stealth characteristics.
Neither does a hundred killowatts of laser light. When the laser lights up you're not stealthy - unless you count blinding any light-sensitive sensors nearby as "stealth". When the laster ISN'T lit, you're not generating steam - except for a short time right after you turned it off. With the right design, "short" can be a matter of seconds.
Meanwhile you're already venting a BUNCH of steam - the combustion product of the hydrogen in the jet fuel with the oxygen in the air. Dump a little extra water vapor in the exhaust (mixed with an equivalent amount of input air) and all you've done is slightly increase the amount of your exhaust and reduce the proportion of carbon and nitrogen oxides (of which your steam cooler produces zero, unlike your engines).
You're not going to get rid of your "steam contrail" unless you turn off your engines. The flight characteristics of a fighter jet with no power have been compared unfavorably with those of a manhole cover.
A guy demoed this at Hackers' years ago.
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3D LCD Display
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He used a grating that he'd generated by writing a little postscript program for a laser printer (to make lines with the right spacing) then copying it to an overhead-projector foil. Put in front of a standard LCD turned 90 degrees (so the three colors of each pixel are aligned vertically) and you have a stereo display.
All these guys did is substitute a second LCD for the grating so they could turn the grating off to switch between a full-resolution 2-d or a half-resolution stereo display.
I wonder if they could dump it into the engine intake air, for a boost? Or just wrap an extra turbopump around a radiator to get an extra couple hundred horses worth of thrust (and a free fan for the radiator) whenever the laser fires.
Galileo is generally thought not to have dropped cannonballs from the Leaning Tower of Pisa -- instead, his writings describe a thought experiment involving two unequal weights tied together with a rope.
THANK you.
I never saw the writing you describe. But this description brings back a memory of how, as a child, I convinced myself that Galileo was right - by coming up with a thought experiment first comparing the rate of fall of two EQUAL weights (two halves of a dumbell to equalize air friction effects) connected by a tiny whisker versus disconnected - then parleyed that into pairs of UNequal weights by comparing a connected pair with a single piece falling alone.
Whitfield Diffie is Sun's chief security officer, and co-invented public-key cryptography.
Actually, Ralph Merkle invented public-key cryptography (too). Merkle's article was SUBMITTED first, though the Diffie-Hellman article was PUBLISHED first while Merkle's was still going through the review process.
Not to disparage any of 'em. Merkle and Diffie & Hellman both invented it separately.
And for you people who follow Nanotech and/or Cryonics, yes it's THAT Ralph Merkle (who didn't invent either cryonics or nanotech, though he does much great work to advance them).
However, that said I think people who ar turned on by kiddie porn have a problem, and people who DISTRIBUTE kiddie porn are criminals.
Actually (if I understand a recent Supreme Court ruling correctly) it's people who MAKE kiddy porn using ACTUAL KIDDIES, and the people who distribute THAT, who are criminals. People who make or distribute kiddie port that was NOT made using underage models are just publishers of erotica or pornography.
The crime is abusing the child and/or being an accessory to abusing the child - not making publcations depicting the abuse of a child, which (regardless of how revolting it might be) falls under the heading of "free press" and into the whole "community standards" morass.
Of course once the government procecutors established a precedent that kiddie porn (using underage models) COULD be banned (as the product of a criminal act - child abuse), they used it to bust tpeople possessing or distributing ALl forms of kiddie porn - including pictures of young-looking OVERage models (computer-processed or otherwise), drawings, and pure-text stories, none of which actually abused a child as a necessary part of their production. This worked for a while and a lot of people were convicted.
But the supremes recently ruled (if I understand it correctly from the little that hit the media) that the burden of proof to show that a child was actually abused in the process of making the porn is on the government.
(My tastes in erotica don't include underripe people [thank goodness]. So I'm afraid that I didn't pay too much attention to the case - other than to think "It's about time!" that the Supremes stomped this particular abuse of government power before it spread to other subjects - like security technology.)
Of course that won't stop them from TRYING AGAIN, probably with some minor variation. And kiddie porn (thanks to its association with child abuse) has few defenders. So people looking for a lucrative new carreer might want to avoid this one, despite the court decision.
(Obligatory caveat: IANAL. Obligatory contextual clarifiation: That doesn't mean I'm a back-door man. B-) )
Alias: Weeds, manure, inedible parts of animal carcases...
You haven't eaten authentic chinese food eh? I'm pretty sure they'd make indians, er, native americans or what ever the politically correct is now, look wasteful.
Right. Which is why I ALMOST didn't include that.
But Chinese standards of edibility are likely to rise with the amount of food that can be grown with a given amount of labor. B-)
Of course, where is a Chinese farmer going to get a reliable source or Hydrogen??
Biomass.
Alias: Weeds, manure, inedible parts of animal carcases...
Leave it to rot and you get lots of methane. Burn that straight, or reform it into hydrogen (using the energy from burning the carbon) for fuel cells. Use the leftover solids for fertilizer.
(Most of the energy is in burning the hydrogen anyhow, and a fuel cell isn't limited to carnot cycle heat-engine efficiency. So you may even be ahead to throw away some of the energy from the carbon to get the hydrogen into a form suitable for fuel cells.)
Now maybe in the "third world" it makes more sense to use an inefficient animal that makes more animals without the aid of a factory. But China has serious industry now. It's a nuclear/space/manufacturing power, no longer a collection of farms with minimal roads.
China was a major civilization for most of history and is now breaking the ideology-bind that had it melting down its infrastructure and returning to world-class status (in more than brute-force army size) as measured by western standards.
(Not to say that what I'm about to describe is what the referenced "illegal music" songs actually are. But this got me thinking.)
Jay-zus, people, can't you see that sampling without permission, and then selling the copies, is illegal for a reason?
Hmm... Resampling bits of another record and playing them at another speed. Using them as notes on a synthesizer keyboard, short riffs, or wildly off-speed as percussion elements.
How is that different from what rap music does? Sliding somebody else's record around on the turntable, playing sampled notes on a drum box,...
Don't the major labels record rap music and sell it at a profit without giving a cent to the group that recorded the disk that's "weep-weep"ing in the foreground?
How many notes do you have to copy before it stops being fair use and starts being plagarism?
Is it more if the notes are warped beyond human recognition?
Is it more - or less - if your song is a parody of the form of which the original is a member?
Is it plagarism if the individual notes of your composition are sampled from some other song rather than played anew in a studio?
Is a song a "copy" if a stock riff common to many songs of the form happens to be sampled from a commercial recording rather than played anew in a studio - and this can be identified by computer processing but NOT by a human ear (even a well-trained one)?
These are not rhetorical questions. Some of them have already been litigated.
"Intellectual Property" - whether patents, copyrights, or trademarks - is a creation of The State. When combined with a right to free expression it creates a multitude of slippery slopes.
This "squishy DRM" system, which puts a unique identifier in each record ("record" in copyright law refers to a copy of a recording) but doesn't restrict fair uses, allows copyright holders to identify those who break the laws so that prosecution can begin. I find it an appropriate compromise...
I see a problem here:
The Super MP3 will come with a tracking signature -- a digital fingerprint -- that will identify the PC that made it.
And if the user is attempting to put out anonymous speech on an MP3 his anonymity is destroyed. Very handy for identifying, prosecuting, and executing dissidents, along with anyone who encodes a tape of their voice for distribution on the Internet.
I bet every totalitarian regime in the world is already drooling.
Of course if this "user serial number" is installed by software you just need to hack the software to change it - or clone someone else's. Setting an individual serial number on open-source encoders will be on the honor system, right? And pirates will honor the rules, and not subvert the unique-ID generator, right? Or are we going to have no open-source encoders for this flashy new format? Even if we have object-only encoders there are ways to subvert them (which I won't even start to describe here thanks to the DMCA.)
I can't make out that tiny chip on the board. But the peltier circuit cooler seems like overkill. If that puppy turns out not to be a major heat source I'd try just putting the bare module in a NEMA enclosure by clamping the PCIA board to the inside of the enclosure gooped with a layer of heatsink compound. For any environment where the card would work in a laptop (like maybe anywhere but a desert, Antarctica, or inside a diesel-electric locomotive) this stunt should work in a NEMA.
If dissipation on that chip is a problem I'd still try it but with a heatsink on that chip or a block of aluminum and two layers of heatsink compound between it and the enclosure.
Now if there's something dissapative UNDER the card it's another matter. But in that case it would probably have trouble on your desk inside that plastic box.
And some folks questioned his motivation for getting this grandiose project into the kernel - was it just to help out, or was it primarily to establish additional hacker reputation for Eric? I'd be willing to give him the benefit of the doubt on this - he did the work.
What's wrong with being motivated by hacker reputaion points? Isn't that what was supposed to replace money in the open source motivational system?
... was it just to help out,...
So an open source developer is evil unless he's motivated solely by altruism?
(That humming sound you hear is the beat between the spin rates of Ayn Rand and Friedrich Hayek.)
C'mon, Bruce. You know better than that.
Regardless of how much we want to help out humanity and all that, SOME of us aren't the leisure class - with old money, idle time, and an indoctrination in the obligations of nobility to give us internal satisfaction when we do something "just to help out" the benighted masses of the common man. Some of us ARE those commoners, with a family, a mortgage, and (if we haven't been laid off in the latest recession) a paycheck that is all that stands between using a shopping cart for groceries and using it for a mobile home.
If we're to contribute time and effort to the open-source codebase we need a way to keep that paycheck coming. Like "reputation points" to put on a resume, to find work the next time the current project is over or the current company goes belly-up.
Maybe Eric doesn't need any more points. But let's not have a big name flaming him for maybe wanting some - and thus convince thousands of onlookers that working open source is a good way to get a BAD rep, so they'd be better off getting that MCSE instead.
With a SAN (Storage Area Network) a bunch of raw disks is made available over a network. Currently this is normally Fiber Channel; iSCSI will bring standard Ethernet to SANs, making it much cheaper.
Bingo. Cheap stock gig-E cards and a driver hack on top of a classic IP stack and you can build a mainframe-reliable file server / disk farm out of commodity boxes from the local PC store.
But that network better not be connected to anything BUT the disks and the file servers' private disk-interface LAN(s), and the file servers better not have IP forwarding enabled (or have a good filter). Else one carefully corrupted packet destroys one file system. (Maybe two or so for RAID.)
I just read that telecoms have an excess of long haul bandwidth, which means that the issues are the cost of the last mile and consumer uptake.
Yes it's the lack of the "last mile" - and content worth paying for its instalation.
Lots of spare fiber (and empty conduit) was laid when the trenches were open, so most of it is dark. Boxes were bought to light up a few fibers, and even when they're all lit we can bump the speed to get a few more powers of two before stringing more long-haul.
But the network speeds and capacities of the first boxes were calculated using what turned out to be Netcom's overstatement of the rate of growth of the internet's bandwidth. For the last 5 or so years it was only doubling, rather than multiplying by 10.
Doubling every year is no slouch for a growth rate, but it's only about 1/3,125 the traffic the designers of the equipment and networks were planning for at this point. (It was 1/125 at the time of the dotcom bubble burst. Maybe some of those dotcoms WOULD have been profitable if the customer base they'd been told to expect actually existed?)
So there's a bandwidth price war at the wholesale level, telecoms folding up as debts come due without revenue to pay them, and equipment suppliers having a REALLY hard time selling any more stuff.
But with the CLECs pretty much all dead, the ILECs and cable companies (with the pre-installed base) have a virtual duopoly on the last mile. So there's no incentive to push cheap fat pipes into your hands. (Markets need THREE suppliers before competition starts driving costs toward price of production. With only two they'd be cutting their own throats to try to cut each others'.)
So there's no cheap last mile bandwidth. But there's virtually no high-bandwith content available to make it worth peoples' while to buy expensive last-mile bandwidth:
- CARP killed "internet radio".
- The RIAA killed Napster, is killing its clones, and finally going after individuals.
- The RIAA and MPAA are scared spitless of allowing any of their members' digital content on the net, for fear of piracy.
So what does that leave Joe Sixpack that will convince him to pay enough extra for high-speed internet that it's profitable to dig up his street and give him a fiber? Better animated popup ads? Most of the rest of the net is more than adequate at moderate speeds.
High-speed internet will be here as soon as there's a "killer app" requiring high-bandwidth that's popular enough to fund a new last-mile deployment, or a cheap-enough last-mile solution is found to be price-competitive with cable and ILEC-based DSL.
Actually, electrical signals in the neighborhood of 10-100MHz propagate through copper at about 0.1C or (18,600 mi/sec or 30,000 km/sec).
That depends on the geometry. Use thicker copper and/or space it farther apart and the signal goes faster. A less lossy dilectric helps, too.
At low frequencies - i.e. where the stray resistance of the line's copper is small compared to the characteristic impedence - the speed is dominated by the dilectric constant of the space between the conductor - and you get your approximate 70% of lightspeed. At higher frequencies (or longer wire) the line acts progressively more like a series-resistors-parallel-capacitors delay line cum low-pass filter. This slows and attenuates the signal, the higher frequencies more than the lower ones.
Selective slowing (phase shift) of the higher frequencies smears out pulses, while selective attenuation weakens them compared to noise.
This can be compensated for to some extent (by amplifying and phase shifting the higher frequencies before transmission and after reception). But there's a limit to how much of that can be done: Too much at the transmitter and you exceed the allowable signal level for the wire (causing cross-talk into the weaker signals going the other way nearby). Go far enough out and the high-frequency signals get down near the noise level, so amplification at the far end just jacks up the noise, too, and they're lost. That's why DSL will only go so far (without a repeater/regenerator).
Telephone wiring was designed for audio of only a few kilohertz, distances of a medium-sized town (rural wiring is a special case), and MANY wires in a bundle. So it uses very thin copper. Central offices were spaced in urban areas so that everybody they feed would be close enough to get a good audio signal. But DSL uses higher frequencies which peter out closer to the source.
Within the distances and frequencies where a copper structure will act as a transmission line rather than being ruined by this effect you're still talking about 70% of c.
But when the poster said "propagate through copper" he MIGHT have been talking about the "skin effect". Eddy currents in the copper due to changes in magnetic fields produce a compensating field, and the result is the field doesn't enter the copper until the eddy currents die due to the copper's resistance. (That's why magnetic fields won't enter a superconductor - to a first approximation.)
But that confuses "propagating through copper" with "propagating along a copper transmission line". In a transmission line (or any other waveguide) the signal and energy don't propagate through the conductor(s). They propagate through the SPACE BETWEEN the conductor(s). Raise the resistance of the conductors and you increase the speed of penetration of signals into the conductor, but slow its propagation along the line.
That's easy do to. It's commonly known as quarter wave plate. Put it in front of your h and v polarized screen and rotate it to 45 degrees from h/v. It will turn h polarized in to right (or left) and v polarized into left (or right, depending on the rotation of the qw plate). See here [gsu.edu] how it works.
Nope - because you only get right-circular and left-circular when the polarization is 45-degrees to the quarter-wave plate's axis. Other angles produce eliptical polarization. So variable intensity (other than on vs. off) is out if you want security against cheap polaroid sunglasses (or viewing the screen in a glare surface).
Also you'll be stuck with a monochrome screen unless you can come up with three narrow-band incoherent colors and a plate that's a quarter-wave for all three.
Slashdot Mirror
Anyone who's done any kind of IOS upgrading on some of the upper-end Cisco routers and Juniper routers knows that the upgraded images aren't always the most stable items around.
So try Redback's Smartedge. It uses a separately-developed code base.
B-)
Philip K Dick didn't write Blade Runner.
Well, he wrote "Do Androids dream of Electric Sheep", which Blade Runner was based on. Happy now?
Nope.
Blade Runner wasn't based on "Do Androids Dream of Electric Sheep?" The MOVIE CALLED "Blade Runner" was based on ""Do Androids Dream of Electric Sheep?"
This is not a silly quibble. Blade Runner was a completely different book (By Alan E. Nourse, if I recall correctly). It's about a future dystopia where medical care is banned (in a misguided attempt to breed out dangerous recessives), except for people who have been sterilized. A very fatal Flu is circulating. There's a vaccine, but because you can't get it unless you volunteer for sterilization you're about to have a situation where all the surviving humans are sterile. One lead character is a "Blade Runner" - a surgical tool bootlegger for an illegal surgeon.
The makers of the movie version of "Do Androids dream of Electric Sheep" blatantly ripped off the name of the unrelated book - apparently because it sounded cool. Nothing in the movie is in any way related to blades or the book with the same title.
So the media empire strikes again, shafting TWO authors for the price of one.
You are basing your argument on an invalid assumption: That all 5% of Mac users would get this service, if it were made available. This is totally false.
No, I'm not assuming that. In the sole-provider case I'm assuming you get the same percentage of adopters among Mac (or whatever) users as you got among Windoze users.
In the multiple provider case I'm assuming that you end up with the same fraction of Mac users adopting the TYPE OF SERVICE/DEVICE as Windows users.
For instance - if the product is satellite networking I'm assuming the same fraction of Mac users as Windows users would buy it - IF the Mac users could get it at all.
That's a MUCH easer case than your strawman.
How many times can we go over this same point? It's the same for Linux and Mac, it's just not economically viable to develop software for something used by less than 5% of the computing masses.
...
Let's phrase this another way:
How much would a company pay for ADVERTISING to get a 5% increase in sales? (And thus a MUCH greater than 5% improvement in profits, since the development is already amortized.)
Now if that same amount bought you the development of an incremental feature (i.e. a Linux or Mac driver) that enables another 5% of the market to use your product, it's the same case. (Actually, if you're currently addressing 90% of the potential market and the new segment is an incremental 5% you're adding 5%/90% or about 5.6%).
But wait, it's better
Suppose that you're currently splitting the market evenly with one other competitor. If YOU do it and HE doesn't, that 5.55% about doubles to 11.1%. With an even split among three competitors the first mover gets about a 16.7% bump in potential sales (and more in profit), and so on.
With something like networking you have a small number of competitors but MAJOR lock-in. First mover gets the prize and KEEPS it. With something (like a device) with more competitors and less lock-in you may not keep it, but you get a BIG boost until your competition wises up.
But WAIT! You don't HAVE to develop it yourself! Publish enough of the interoperability specs and - at least for Linux - SOMEONE ELSE will do it FOR you! You get the benefits and do only a tiny fraction of the work.
Your work consists mostly editing your internal documents into an externally-releasable one that will enable a developer without giving away your trade-secret farm. But don't get too paranoid: Your competitors are ALREADY reverse-engineering you. You should have your critrical IP already locked up in patent-pending, which will keep your competition at bay if you publish more than you intended. Meanwhile, better specs mean better and sooner community software to enable your sales.
Network operators might have some issues with security - but that's already been addressed elsewhere. (Bottom line is that the black hats will get you anyhow if you're already BADLY broken, regardless of whether you publish, while if you're reasonably secure (i.e. only a little flakey) the exposure will get the white hats on your side and you'll probably increase your lead in the arms race.)
Every time someone calls with a question, it costs the company money. The quicker you can answer their question and get them off the phone, the better. This means minimizing the number of different systems your support folks have to be trained for.
So have the bulk of them trained for the bulk operating system, a few trained for each little one, and TRANSFER THE CALL if you get one for a little opsys. We are talking NETWORK companies, right?
Heck - I bet the little guys would put up with a half-day delay and callback - and be grateful they could buy your stuff at all. YOU get to schedule the calls, rather than fielding them when they arrive - increasing the efficiency of the little-opsys helpers.
Yeah, but water is heavy and would run out and need to be refilled.
So does the fuel for the laser - or the engines. It's just another tank (and a small one) to be filled. (If the laser is chemically-pumped you could include the cooling water in the fuel canister and reload just like you would a machine gun or missile pod.)
Aerospace engineers _hate_ weight more than anything (including enemy aerospace engineers).
Ablative cooling - in the form of boiling water - has one of the highest cooling-to-weight ratios of any cooling system.
Vent the steam. The F-35 is suppose to be stealthy. Leaving a con trail of vented steam does not help the stealth characteristics.
Neither does a hundred killowatts of laser light. When the laser lights up you're not stealthy - unless you count blinding any light-sensitive sensors nearby as "stealth". When the laster ISN'T lit, you're not generating steam - except for a short time right after you turned it off. With the right design, "short" can be a matter of seconds.
Meanwhile you're already venting a BUNCH of steam - the combustion product of the hydrogen in the jet fuel with the oxygen in the air. Dump a little extra water vapor in the exhaust (mixed with an equivalent amount of input air) and all you've done is slightly increase the amount of your exhaust and reduce the proportion of carbon and nitrogen oxides (of which your steam cooler produces zero, unlike your engines).
You're not going to get rid of your "steam contrail" unless you turn off your engines. The flight characteristics of a fighter jet with no power have been compared unfavorably with those of a manhole cover.
He used a grating that he'd generated by writing a little postscript program for a laser printer (to make lines with the right spacing) then copying it to an overhead-projector foil. Put in front of a standard LCD turned 90 degrees (so the three colors of each pixel are aligned vertically) and you have a stereo display.
All these guys did is substitute a second LCD for the grating so they could turn the grating off to switch between a full-resolution 2-d or a half-resolution stereo display.
... Or just boil some water and vent the steam. 900 Kw isn't much when it's not continuous, and boiling water takes a LOT of energy.
Thats a lot of heat!
900 Kw? That's only about 1200 horsepower.
I wonder if they could dump it into the engine intake air, for a boost? Or just wrap an extra turbopump around a radiator to get an extra couple hundred horses worth of thrust (and a free fan for the radiator) whenever the laser fires.
Galileo is generally thought not to have dropped cannonballs from the Leaning Tower of Pisa -- instead, his writings describe a thought experiment involving two unequal weights tied together with a rope.
THANK you.
I never saw the writing you describe. But this description brings back a memory of how, as a child, I convinced myself that Galileo was right - by coming up with a thought experiment first comparing the rate of fall of two EQUAL weights (two halves of a dumbell to equalize air friction effects) connected by a tiny whisker versus disconnected - then parleyed that into pairs of UNequal weights by comparing a connected pair with a single piece falling alone.
Whitfield Diffie is Sun's chief security officer, and co-invented public-key cryptography.
Actually, Ralph Merkle invented public-key cryptography (too). Merkle's article was SUBMITTED first, though the Diffie-Hellman article was PUBLISHED first while Merkle's was still going through the review process.
Not to disparage any of 'em. Merkle and Diffie & Hellman both invented it separately.
And for you people who follow Nanotech and/or Cryonics, yes it's THAT Ralph Merkle (who didn't invent either cryonics or nanotech, though he does much great work to advance them).
However, that said I think people who ar turned on by kiddie porn have a problem, and people who DISTRIBUTE kiddie porn are criminals.
Actually (if I understand a recent Supreme Court ruling correctly) it's people who MAKE kiddy porn using ACTUAL KIDDIES, and the people who distribute THAT, who are criminals. People who make or distribute kiddie port that was NOT made using underage models are just publishers of erotica or pornography.
The crime is abusing the child and/or being an accessory to abusing the child - not making publcations depicting the abuse of a child, which (regardless of how revolting it might be) falls under the heading of "free press" and into the whole "community standards" morass.
Of course once the government procecutors established a precedent that kiddie porn (using underage models) COULD be banned (as the product of a criminal act - child abuse), they used it to bust tpeople possessing or distributing ALl forms of kiddie porn - including pictures of young-looking OVERage models (computer-processed or otherwise), drawings, and pure-text stories, none of which actually abused a child as a necessary part of their production. This worked for a while and a lot of people were convicted.
But the supremes recently ruled (if I understand it correctly from the little that hit the media) that the burden of proof to show that a child was actually abused in the process of making the porn is on the government.
(My tastes in erotica don't include underripe people [thank goodness]. So I'm afraid that I didn't pay too much attention to the case - other than to think "It's about time!" that the Supremes stomped this particular abuse of government power before it spread to other subjects - like security technology.)
Of course that won't stop them from TRYING AGAIN, probably with some minor variation. And kiddie porn (thanks to its association with child abuse) has few defenders. So people looking for a lucrative new carreer might want to avoid this one, despite the court decision.
(Obligatory caveat: IANAL. Obligatory contextual clarifiation: That doesn't mean I'm a back-door man. B-) )
One thing that will get the Supreme Court to grant Cert is when two Federal Circuits come to conflicting decisions on a point of law.
So perhaps in a year or two we'll hear from them on this and settle the matter once and for all.
Alias: Weeds, manure, inedible parts of animal carcases...
You haven't eaten authentic chinese food eh? I'm pretty sure they'd make indians, er, native americans or what ever the politically correct is now, look wasteful.
Right. Which is why I ALMOST didn't include that.
But Chinese standards of edibility are likely to rise with the amount of food that can be grown with a given amount of labor. B-)
Of course, where is a Chinese farmer going to get a reliable source or Hydrogen??
Biomass.
Alias: Weeds, manure, inedible parts of animal carcases...
Leave it to rot and you get lots of methane. Burn that straight, or reform it into hydrogen (using the energy from burning the carbon) for fuel cells. Use the leftover solids for fertilizer.
(Most of the energy is in burning the hydrogen anyhow, and a fuel cell isn't limited to carnot cycle heat-engine efficiency. So you may even be ahead to throw away some of the energy from the carbon to get the hydrogen into a form suitable for fuel cells.)
Now maybe in the "third world" it makes more sense to use an inefficient animal that makes more animals without the aid of a factory. But China has serious industry now. It's a nuclear/space/manufacturing power, no longer a collection of farms with minimal roads.
China was a major civilization for most of history and is now breaking the ideology-bind that had it melting down its infrastructure and returning to world-class status (in more than brute-force army size) as measured by western standards.
(Not to say that what I'm about to describe is what the referenced "illegal music" songs actually are. But this got me thinking.)
...
Jay-zus, people, can't you see that sampling without permission, and then selling the copies, is illegal for a reason?
Hmm... Resampling bits of another record and playing them at another speed. Using them as notes on a synthesizer keyboard, short riffs, or wildly off-speed as percussion elements.
How is that different from what rap music does? Sliding somebody else's record around on the turntable, playing sampled notes on a drum box,
Don't the major labels record rap music and sell it at a profit without giving a cent to the group that recorded the disk that's "weep-weep"ing in the foreground?
How many notes do you have to copy before it stops being fair use and starts being plagarism?
Is it more if the notes are warped beyond human recognition?
Is it more - or less - if your song is a parody of the form of which the original is a member?
Is it plagarism if the individual notes of your composition are sampled from some other song rather than played anew in a studio?
Is a song a "copy" if a stock riff common to many songs of the form happens to be sampled from a commercial recording rather than played anew in a studio - and this can be identified by computer processing but NOT by a human ear (even a well-trained one)?
These are not rhetorical questions. Some of them have already been litigated.
"Intellectual Property" - whether patents, copyrights, or trademarks - is a creation of The State. When combined with a right to free expression it creates a multitude of slippery slopes.
This "squishy DRM" system, which puts a unique identifier in each record ("record" in copyright law refers to a copy of a recording) but doesn't restrict fair uses, allows copyright holders to identify those who break the laws so that prosecution can begin. I find it an appropriate compromise ...
I see a problem here:
The Super MP3 will come with a tracking signature -- a digital fingerprint -- that will identify the PC that made it.
And if the user is attempting to put out anonymous speech on an MP3 his anonymity is destroyed. Very handy for identifying, prosecuting, and executing dissidents, along with anyone who encodes a tape of their voice for distribution on the Internet.
I bet every totalitarian regime in the world is already drooling.
Of course if this "user serial number" is installed by software you just need to hack the software to change it - or clone someone else's. Setting an individual serial number on open-source encoders will be on the honor system, right? And pirates will honor the rules, and not subvert the unique-ID generator, right? Or are we going to have no open-source encoders for this flashy new format? Even if we have object-only encoders there are ways to subvert them (which I won't even start to describe here thanks to the DMCA.)
There have been some cool mods like:
r oo t=dslalt~mode=flatu m/remark,4123612~roo t=dslalt~mode=flat~start=0
http://www.dslreports.com/forum/remark,4220109~
http://www.dslreports.com/for
I can't make out that tiny chip on the board. But the peltier circuit cooler seems like overkill. If that puppy turns out not to be a major heat source I'd try just putting the bare module in a NEMA enclosure by clamping the PCIA board to the inside of the enclosure gooped with a layer of heatsink compound. For any environment where the card would work in a laptop (like maybe anywhere but a desert, Antarctica, or inside a diesel-electric locomotive) this stunt should work in a NEMA.
If dissipation on that chip is a problem I'd still try it but with a heatsink on that chip or a block of aluminum and two layers of heatsink compound between it and the enclosure.
Now if there's something dissapative UNDER the card it's another matter. But in that case it would probably have trouble on your desk inside that plastic box.
And some folks questioned his motivation for getting this grandiose project into the kernel - was it just to help out, or was it primarily to establish additional hacker reputation for Eric? I'd be willing to give him the benefit of the doubt on this - he did the work.
... was it just to help out, ...
What's wrong with being motivated by hacker reputaion points? Isn't that what was supposed to replace money in the open source motivational system?
So an open source developer is evil unless he's motivated solely by altruism?
(That humming sound you hear is the beat between the spin rates of Ayn Rand and Friedrich Hayek.)
C'mon, Bruce. You know better than that.
Regardless of how much we want to help out humanity and all that, SOME of us aren't the leisure class - with old money, idle time, and an indoctrination in the obligations of nobility to give us internal satisfaction when we do something "just to help out" the benighted masses of the common man. Some of us ARE those commoners, with a family, a mortgage, and (if we haven't been laid off in the latest recession) a paycheck that is all that stands between using a shopping cart for groceries and using it for a mobile home.
If we're to contribute time and effort to the open-source codebase we need a way to keep that paycheck coming. Like "reputation points" to put on a resume, to find work the next time the current project is over or the current company goes belly-up.
Maybe Eric doesn't need any more points. But let's not have a big name flaming him for maybe wanting some - and thus convince thousands of onlookers that working open source is a good way to get a BAD rep, so they'd be better off getting that MCSE instead.
With a SAN (Storage Area Network) a bunch of raw disks is made available over a network. Currently this is normally Fiber Channel; iSCSI will bring standard Ethernet to SANs, making it much cheaper.
Bingo. Cheap stock gig-E cards and a driver hack on top of a classic IP stack and you can build a mainframe-reliable file server / disk farm out of commodity boxes from the local PC store.
But that network better not be connected to anything BUT the disks and the file servers' private disk-interface LAN(s), and the file servers better not have IP forwarding enabled (or have a good filter). Else one carefully corrupted packet destroys one file system. (Maybe two or so for RAID.)
I just read that telecoms have an excess of long haul bandwidth, which means that the issues are the cost of the last mile and consumer uptake.
Yes it's the lack of the "last mile" - and content worth paying for its instalation.
Lots of spare fiber (and empty conduit) was laid when the trenches were open, so most of it is dark. Boxes were bought to light up a few fibers, and even when they're all lit we can bump the speed to get a few more powers of two before stringing more long-haul.
But the network speeds and capacities of the first boxes were calculated using what turned out to be Netcom's overstatement of the rate of growth of the internet's bandwidth. For the last 5 or so years it was only doubling, rather than multiplying by 10.
Doubling every year is no slouch for a growth rate, but it's only about 1/3,125 the traffic the designers of the equipment and networks were planning for at this point. (It was 1/125 at the time of the dotcom bubble burst. Maybe some of those dotcoms WOULD have been profitable if the customer base they'd been told to expect actually existed?)
So there's a bandwidth price war at the wholesale level, telecoms folding up as debts come due without revenue to pay them, and equipment suppliers having a REALLY hard time selling any more stuff.
But with the CLECs pretty much all dead, the ILECs and cable companies (with the pre-installed base) have a virtual duopoly on the last mile. So there's no incentive to push cheap fat pipes into your hands. (Markets need THREE suppliers before competition starts driving costs toward price of production. With only two they'd be cutting their own throats to try to cut each others'.)
So there's no cheap last mile bandwidth. But there's virtually no high-bandwith content available to make it worth peoples' while to buy expensive last-mile bandwidth:
- CARP killed "internet radio".
- The RIAA killed Napster, is killing its clones, and finally going after individuals.
- The RIAA and MPAA are scared spitless of allowing any of their members' digital content on the net, for fear of piracy.
So what does that leave Joe Sixpack that will convince him to pay enough extra for high-speed internet that it's profitable to dig up his street and give him a fiber? Better animated popup ads? Most of the rest of the net is more than adequate at moderate speeds.
High-speed internet will be here as soon as there's a "killer app" requiring high-bandwidth that's popular enough to fund a new last-mile deployment, or a cheap-enough last-mile solution is found to be price-competitive with cable and ILEC-based DSL.
Actually, electrical signals in the neighborhood of 10-100MHz propagate through copper at about 0.1C or (18,600 mi/sec or 30,000 km/sec).
That depends on the geometry. Use thicker copper and/or space it farther apart and the signal goes faster. A less lossy dilectric helps, too.
At low frequencies - i.e. where the stray resistance of the line's copper is small compared to the characteristic impedence - the speed is dominated by the dilectric constant of the space between the conductor - and you get your approximate 70% of lightspeed. At higher frequencies (or longer wire) the line acts progressively more like a series-resistors-parallel-capacitors delay line cum low-pass filter. This slows and attenuates the signal, the higher frequencies more than the lower ones.
Selective slowing (phase shift) of the higher frequencies smears out pulses, while selective attenuation weakens them compared to noise.
This can be compensated for to some extent (by amplifying and phase shifting the higher frequencies before transmission and after reception). But there's a limit to how much of that can be done: Too much at the transmitter and you exceed the allowable signal level for the wire (causing cross-talk into the weaker signals going the other way nearby). Go far enough out and the high-frequency signals get down near the noise level, so amplification at the far end just jacks up the noise, too, and they're lost. That's why DSL will only go so far (without a repeater/regenerator).
Telephone wiring was designed for audio of only a few kilohertz, distances of a medium-sized town (rural wiring is a special case), and MANY wires in a bundle. So it uses very thin copper. Central offices were spaced in urban areas so that everybody they feed would be close enough to get a good audio signal. But DSL uses higher frequencies which peter out closer to the source.
Within the distances and frequencies where a copper structure will act as a transmission line rather than being ruined by this effect you're still talking about 70% of c.
But when the poster said "propagate through copper" he MIGHT have been talking about the "skin effect". Eddy currents in the copper due to changes in magnetic fields produce a compensating field, and the result is the field doesn't enter the copper until the eddy currents die due to the copper's resistance. (That's why magnetic fields won't enter a superconductor - to a first approximation.)
But that confuses "propagating through copper" with "propagating along a copper transmission line". In a transmission line (or any other waveguide) the signal and energy don't propagate
through the conductor(s). They propagate through the SPACE BETWEEN the conductor(s). Raise the resistance of the conductors and you increase the speed of penetration of signals into the conductor, but slow its propagation along the line.
every single digital optical cable I've ever seen is plastic.
I can assure you, as someone working in the telecom industry, that the fibers we're working with are glass.
Are you sure you're not confusing the fiber itself with the layers of plastic protective armor around it?
That's easy do to. It's commonly known as quarter wave plate. Put it in front of your h and v polarized screen and rotate it to 45 degrees from h/v. It will turn h polarized in to right (or left) and v polarized into left (or right, depending on the rotation of the qw plate). See here [gsu.edu] how it works.
Nope - because you only get right-circular and left-circular when the polarization is 45-degrees to the quarter-wave plate's axis. Other angles produce eliptical polarization. So variable intensity (other than on vs. off) is out if you want security against cheap polaroid sunglasses (or viewing the screen in a glare surface).
Also you'll be stuck with a monochrome screen unless you can come up with three narrow-band incoherent colors and a plate that's a quarter-wave for all three.