Not knocking this, I promise, just a discussion point: aren't games inadvertently changing things as it is?
Of course they are -- in fact, it's unavoidable. Anything anybody does causes at least some change, and games are no exception to that.
This has two differences: 1) that you've written the game with some specific change(s) in mind, and 2) that the changes you had in mind fit the organizers' idea of social consciousness.
Even if, for example, GTA IV was written with the specific idea of changing people's attitudes, it probably wouldn't qualify for this show. My own experience has been that shows like this are largely self-contradictory: they claim it's about socially conscious games -- but they nearly automatically disqualify anything that's really fun as not being sufficiently socially conscious...
My point is this, Microsoft may be the devil, but the ubiquity of its (sometimes bad) products has resulted in a marketplace with competing products that are better than Microsoft products because they MUST be in order to compete.
Without getting into details of MS products in particular, I think there's a strong possibility of exactly the opposite happening. Specifically, a product that's perceived as free and sufficient reduces or removes the motivation for anybody to compete, even if they could produce something that's a lot better and might even be substantially less expensive when all factors are taken into account.
Where you have entire IT departments which are used to doing 90% of their work (desktop AND server) on Microsoft products, the effort and expense of suddenly discovering that Microsoft products are now verboten for new systems would be rather more than most could realistically bear.
You're absolutely right. This is why Novell Netware and Visicalc...oops I mean Lotus 1-2-3, continue to dominate the market to this day!
Instead of trying to convince everyone on Earth to change all existing software, why doesn't Microsoft just make the next version of Windows have a process handler that can process single threads on multiple cores at once? Actually technically I think Intel could do that internally on their processors too sort of like RAID for cores.
Intel's been doing that (to some degree) since the Pentium, and they increased it a lot in the Pentium Pro/Pentium II. It works reasonably well up to a point (modern chips typically execute an average of two instructions per clock cycle) but definitely has limits.
Compilers to automatically detect when instructions can be executed in parallel have been around for years. Cray had vectorizing compilers by the late 1970's, and within rather specific limits, they worked perfectly well. Just for example, if you wrote a loop like:
for (int i=0; i<256; i++) a[i] = b[i] * c[i];
they'd break the loop down into four actual executions of a loop, each of which worked on 64 items in parallel. It had independent execution units, so at a given time it'd normally be loading one set of 64 items into one set of registers, executing multiplications on a second set of 64 items, and storing results from a third set of 64 registers.
That has a couple of problems though. First of all, if you're not careful, it's pretty easy to create loops with (apparent) dependencies from one iteration to the next, so the compiler can't parallelize the code. Second, this works well for vector processors, but probably not nearly so well for a large number of completely independent processors (which have higher communication overhead, meaning that starting up things to happen in parallel is more expensive).
If you're willing to provide the compiler with a little help, it can do quite a bit more, such as with MPI. The standard MPI interface is pretty low-level, but if you want to do the job in C++, Boost.MPI helps out quite a bit (cheap plug: if you want to know more, consider attending Boostcon '08).
Although VHDL is a hardware description language, couldn't similar concepts be used to make a parallel centric computer programming language?
Sure. In fact, VHDL is based (closely) on Ada, which allows pretty similar things. The relevant differences are less between the languages than how they're used. Ada that was written in the same style as most VHDL would have a high level of parallelism as well.
That's rarely done though, because designing hardware in VHDL (or Verilog, etc.) is expensive, largely because designing things this way is difficult. Virtually nobody's willing to put up with the long lead times and extremely high initial expense of such a design for software, unless it's doing something that really gains a tremendous amount from doing so.
Of course, that hasn't stopped people from trying. The Transputer was one early attempt. The Ambric is on the market now, and apparently sells pretty decently into a few specialized markets (e.g. video encoding/decoding) but I've never heard of anybody even advocating that it was a practical tool for a typical desktop computer.
You might as well acquiesce to the fact that it ain't gonna happen. Unless a company comes along that is influential enough to "get things done."
There is no such company.
Microsoft originally designed Windows NT to be portable, and ported it to most of the popular architectures, including MIPS, PowerPC and the DEC Alpha (and probably SPARC, though it never made it to market). All of those have died, because they didn't sell well enough to stay on the market. Right now, Windows is available for the Itanium, but I certainly don't know anybody who's running it on one.
Intel has tried as well -- the Itanium is only the latest attempt at superseding the x86. In fact, the 8086 was originally designed specifically to be clumsy to program, in the hope that it would leave room for the iAPX432 to take over the market when it became available. Intel failed on both counts: the 432 as buggy as sin, and by the time it was available at all, the IBM PC had already taken the market so completely that Intel never produced a 432 that worked worth anything.
Of course, quite a few others have tried as well -- at one time, Sun pushed the SPARC as the architecture that would kill the x86. Sun still sells SPARC boxes, but they sell x86 servers as well.
From a slightly different viewpoint, the masses have already moved onto something else -- but gained very little from doing so. None of the current game consoles uses an x86. While the PS3 and Xbox 360 both have a lot of computing power, the Wii (with substantially less than either one) is what really gets a lot of people excited. The excitement isn't over the CPU though -- it's over the controllers.
The masses also buy a lot of CPUs in cell/portable phones. For this market, the ARM is the dominant architecture. It has excellent power consumption characteristics and such, which is nice, but in the end nobody really cares all that much that it's an ARM.
If, for example, Motorola 680x0 had dominated the market instead of the x86, life would be a bit nicer for those of us who still hack out a bit of assembly language now and then, but the reality is that most people would hardly notice or care. Apple has switched from the 680x0 to the PowerPC to the x86, and most users hardly batted an eye as they did so. To the typical user, CPU architecture is about as relevant as the brand of pipes used to bring water into their house.
However, there is a minor weakness that should be pointed out, and could be corrected in the next edition. In most of the sections' examples, Stubblebine wisely formats the code so that every left brace ("{") is on the same line as the beginning of the statement that uses that brace, and each closing brace ("}") is lined up directly underneath the first character of the statement. This format saves space and makes it easier to match up the statement with its corresponding close brace. However, in the.NET / C# and PCRE library sections, the open braces consume their own lines, and also are indented inconsistently, as are the close braces, which makes the code less readable, as well as less consistent among the sections.
A minor correction:
However, there is a minor weakness that should be pointed out, and could be corrected in the next edition. Specifically, the book includes a section on.NET/C# and PCRE. By the time the next edition is needed, Microsoft will undoubtedly have moved on to new languages running in a new environment, as well as "enhanced" regular expressions "to provide better security and a syntax that is more approachable by beginners."
They seem to have departed from standard practice in two ways. First, they use an on-chip DC-DC converter to dynamically scale the voltage down to the minimum required to meet whatever performance metric is specified.
That's not really new by itself. Just for an obvious example, most Flash ROM chips need a relatively high voltage for writing. Early Flash ROM chips used dual power supplies to support that, but most current Flash ROM chips use a single external power supply and an on-board DC-DC converter to produce the write voltage.
It's also not clear (at least to me) whether they're really scaling the supply voltage down to the point needed, or possibly scaling it up as needed. As noted above, scaling up has been common (at least for some kinds of chips) for quite a while. Scaling down isn't nearly as common, but I'm pretty sure some kinds of chips (for some reason, A->D converters come to mind) have done that as well.
Second, they intend to power it using some kind of energy-harvesting technique (namely human body heat). I agree the reduction of power is just first-order physics, but how they do it is quite interesting.
Energy harvesting is mostly a matter of reducing the power usage to the point that it becomes practical. RFID tags (for one obvious example) are powered entirely by the transmitter that reads them. That is, to read one, you put the reader close to the tag. The tag has an antenna that picks up the radio signal from the reader, and uses it to charge a capacitor. The power from the capacitor is used to transmit a signal back to the reader.
Simply using heat to generate electricity is well known as well. Thermocouples, which generate electricity directly from a temperature difference have been known for a long time. Most electrical power plants start by producing heat, use that to boil water, then use the steam to run a turbine.
This seems to be a complete other kind of advancement than regular chip evolution we've seen so far.
There's not enough in TFA to say for sure, but I'd guess rather the opposite. The main thing they mention is a lower power supply voltage. Power supply voltages have been dropping steadily for a long time. Once upon a time, the most common logic family was the 7400 series, which all used 5 volt power supplies. Somewhat later 3.3 volt CMOS logic was introduced. Most CPUs, memory, etc., now use somewhere between 1 and 2 volts.
For the most part, you get a trade-off between voltage and speed -- with a higher voltage, you can charge up a more reactive load more quickly, giving faster rise and fall times. That translates directly to higher bus speed.
At the same time, the power you use is the product of the voltage and the current, so as you raise the voltage you raise the power usage. Worse, the current you drive through a given impedance also rises linearly with the voltage -- so the power usage is proportional to the square of the voltage.
That (probably) explains to a large degree how/why they've reduced the power usage by a ration of 10:1 by reducing the voltage by a ratio of something like 4:1 (in theory, a 10:1 power reduction should imply a voltage reduction by the square root of 10, roughly 3.16).
In any case, however, nothing in the article really suggests that they've departed a great deal from the path everybody's been following for quite a while. Of course, they may have done something truly radical here -- but based on what they've said, that isn't necessarily the case.
The protest against the visit was spearheaded by physicist Marcello Cini who wrote the rector complaining of an 'incredible violation" of the university's autonomy. Cini said of Benedict's cancellation: 'By canceling, he is playing the victim, which is very intelligent. It will be a pretext for accusing us of refusing dialogue.'"
Let's see. He asks that the visit be canceled. The visit gets canceled. Then he complains about the visit having been canceled.
This sounds like the guy's ready to complain no matter what happens.
If you read through the brief, you get the sense that the EFF couldn't possibly care less about this particular defendant, and is much more worried about the (possibly far reaching) precedent that will be set as a result of this case - especially since the defendant is appearing before the court pro se.
That's more or less the natural result of this being an amicus curiae brief rather than a brief directly on behalf of the defendant.
It may not make sense to some people, but in the eyes of the record industry, a ripped MP3 file goes from "authorized" to "unauthorized" when it's placed into your P2P share directory... even though it's the same file.
That's certainly one way to interpret what they've filed, but it's far from the only one. In any case, the position does not seem to be supported by the law, which specifically says that such an infringement requires an actual copy to an unauthorized individual, such as somebody else downloading the file from the shared directory, not just putting the file into the shared directory in the first place.
To make a long story short, you may be right about what the industry believes (or wants to believe), but even if you are it makes no real difference. This position does not appear to be in accord with the plain meaning of the law, or the positions taken by the courts in the past.
The guy took CDs he bought. He ripped them to mp3. He then loaded those mp3s into some file-sharing program.
There's your fundamental mistake -- at least as far as I can see, he did not load the MP3s into a file sharing program. Rather, he:
1) loaded the MP3s onto his computer
2) completely separately installed a file sharing program
There seems to be no evidence at all that he really took any action to connect the two -- rather, the file sharing program, by default, shares the directory where he happened to put the files. He probably didn't even explicitly select that directory for the files -- it was probably selected by default as well.
I ask this question every time I see a "patents/copyrights/etc should be limited to X years" debate. The question is, what right do you have to limit me benefitting from my work?
It would be equally valid to ask what makes you think you have any right to benefit from your work at all?
There doesn't seem to be anything in the Bible, Koran, etc., granting a divine right to benefit from your work. The US constitution does grant such a right. In doing so, it states that the reason for doing so is to promote progress, and specifically states that such rights shall be granted for only a limited time.
In other words, the exact document that gives the right (in the US) in the first place also places an explicit limit upon that right. As such, there seems to be far more reason to question why you think you can/could/should have an unlimited version of that right at all.
I am under no obligation to give away my work just because the public finds it useful.
You are under no obligation to publish your work at all, whether the public finds it useful or not. The public has granted you a limited right to control over your work, and it's up to you to decide whether that right provides you with sufficient incentive to publish your work or not. If not, feel free to never publish the work at all. If so, feel free to do so. What's happened in the case of copyright, however, is that people published their work, and then get congress to change the law so they continued to benefit long after the original terms expired.
What right does any/.er, any government, anybody at all, have to steal my work?
If you sell your work to somebody, what gives you a right to control how they use it at all? If I buy a table, or chair, or bed, etc., I pay for the object itself. If I decide to go into the business of selling tables, chairs, beds, etc., and sell ones just like the one I bought, I'm perfectly within my rights to do so. That's not theft by any stretch of the imagination. When I bought the original, I gained the right to use it as I saw fit -- including making copies of it if I saw fit to do so.
When something is truly stolen, that deprives the owner of their actual property. Making (for example) a copy of a song doesn't deprive the original owner of their copies of that song, therefore it is simply not theft at all.
Lawmakers, however, have long recognized that by providing you with rights beyond protection from actual theft they are likely to provide you with incentive to publish your work that would almost certainly otherwise be absent. In doing so, there has been a clear (and reasonably consistent) recognition of the fact that they're doing so for a specific reason, and therefore should limit those extra rights to only what's needed to achieve that specific purpose.
To make a long story short, the rights were granted by law only to achieve a specific purpose, and specifically for the benefit of the public. They are limited for precisely the same reasons, because doing so benefits the public. It's also worth noting that in reality, it is primarily the creators of original works that benefit from the limitations on copyright. For example, many of Disney's classic movies are based on existing stories such as Snow White and the Seven Dwarves, Cinderella, The Little Mermaid, Beauty and the Beast, and so on.
With all this improvement, why haven't we gotten to the point where I can buy a 20 GB hard for $20?
Two basic reasons. First of all, the basic overhead costs like packaging and shipping are basically fixed, regardless of the capacity of the hard drive. While they have little effect on the cost of a $200 item, they'd eat you alive trying to sell hard drives for $20.
The second reason is closely related: the cost of building a hard drive depends relatively little on its capacity. You can predict the cost of the drive fairly accurately based only on its form factor. Yes, as the capacity goes up things like the heads and the coatings on the platters change, but they don't change the cost all that much. Obviously when you put more platters in a drive, the cost goes up, but within the typical 1/3 ht. form factor, you don't have room for enough platters to cause anything like an order of magnitude difference in cost.
The rule is really very simple: standard hard drives (i.e. excluding things like micro-drives) really have a nearly constant price of roughly $250/pound. Most of what's changed over time has been the amount of data you can store per pound.
It takes Days- as in two or three- to cool down a steam plant, even one attached to a nuclear power plant.
I guess I should have been a bit more clear. When the plant is still operating normally, so you can continue to run steam through it, it's absolutely true that cooling down only takes a few days. As you run steam through, it pulls out a lot of heat relatively quickly.
I was talking about a situation where you have a problem sufficient that you can't run steam through any more. In a case like this, cooling down takes drastically longer -- for normal use you (of course) have the hot parts of the plant heavily insulated to retain the heat as well as possible. I just spent a bit of time re-reading accounts of the incidents at Three Mile Island and Chernobyl, but I haven't been able to find any that say exactly how long it took to cool down the steam plant to the point that human entry was possible. The Three Mile Island accident took place in late March of 1979, and it was July of 1980 when the first person re-entered the reactor chamber (everybody reports on that!) but my recollection from the time is that it was around May or so before the steam area was reentered -- though I'll openly admit I'm going from memory, and it's obviously been quite a long time. Of course, it's also possible that reentry into some parts of the plant were delayed longer than strictly necessary, simply due to the other concerns at the time.
Actually, the most obvious way to get past petroleum is not dirty, insecure, expensive nukes, but clean, safe, cheap wind turbines.
Taking a look at some actual facts doesn't seem to support your contention, at least as to expense. I suspect the danger level (especially if you count birds and such) is much higher for wind generation as well.
Don't get me wrong: I'm not against wind turbines -- but I think you're overstating what are really rather modest advantages, at least at the present time.
All I can say though is I hope we can easily convert fission nuke plants to fusion when we perfect it cuz fission isn't going to last much longer.
As several posts (including one of mine) have pointed out, fission can be used for quite a while (even if you don't take breeder reactors into account). Converting a fission plant to a fusion plant would be interesting. Basically, the reactor itself would almost certainly be scrapped entirely. The turbines and generators, OTOH, wouldn't generally care whether the steam was produced by fusion or fission, so they could probably remain more or less intact.
Interestingly, when/if you actually look carefully at the history of accidents (and near-accidents) in nuclear power plants, most of the problems are surprisingly mundane. In fact, it looks like a lot of the problems are basically mechanical -- things like building a steam valve that simply opens and closes dependably for years at a time, even though the steam involved is at high pressure and temperature (e.g. ~300 degrees C and 2000+ PSI). Quite a bit of research has been done into temperatures and pressures of primary coolants (near the bottom of the page).
Even if a repair is strictly in the steam part of the plant (where nuclear radiation isn't a problem) it can take months to cool hundreds of tons of steel, concrete, etc., down from its normal operating temperature to the point that a person can enter and work on something. This makes the cost of repairs so high that the system must be engineered to run for years (preferably decades) at a time without them.
As closely as I can figure it, there are about 11_515_262_616_000 metric tons of Uranium-235 in the earth's crust.
The numbers work out as follows: The mass of the earth is about 5.98e24 kilograms. The crust is about.099% of that. Uranium occurs at a rate of about
2.7 milligrams per kilogram in the crust, and about 0.7204% of that is Uranium-235.
Some of that would undoubtedly take more energy to mine, purify and enrich to usable levels than it would produce as output -- but even if only one percent is usable, it still works out to quite a large energy supply. Enrichment isn't necessarily needed -- but if you don't enrich the Uranium, you typically also have to moderate your reactor with deuterium, and it takes a fair amount of energy to purify deuterium from normal water as well. In any case, once you've purified the Uranium, enrichment is roughly a fixed cost regardless of the original source.
There's also Uranium in sea water, though the rate is quite low (3.2 micrograms per liter). That might be a practical supply as well, but I don't know enough about how difficult it is to purify from sea water to be certain. My immediate guess is that if the only alternatives were things like solar or wind power, somebody could figure out a practical way to do it.
A mere 200 lines probably constitutes "fair use", which is built into copyright law.
I doubt it. Fair use means convincing a court that the use you're making of the material is really fair. In many cases, that means writing something that's sufficiently different that the court believes you're not really competing directly with the original author -- for example, a book review that quotes a few lines from a book isn't likely to be used as a substitute for buying the original story. Quoting a few particularly telling lines can give a good idea of the book's topic and style, so doing so will generally be considered fair use. This case seems to be almost entirely different however -- it's not writing something new or original about that code, but simply using it as it was originally intended. Even when courts do look at the amount copied, they rarely look exclusively at just the raw amount involved -- they frequently look at both the percentage of the original that was copied, and the percentage that the copied material constitutes of the final work in which it is copied. If I copy 200 lines from War and Peace, it would generally be easier to justify than if the 200 lines being copied were virtually 100% of the original (which sounds like it might easily be the case here). Likewise, if I write a long book and copy one-liners from here and there as titles to chapters and such, it's easier to justify than if all I've done is paste in a single large quote from somewhere, and that's all I'm publishing.
Even though I doubt this would qualify as fair use, publishing exactly the same code under other circumstances might well be fair use. For example, if I was writing a book on coding style, and included all 200 lines of this snippet as an example, and wrote a line-by-line analysis of how it was written, that would almost certainly improve the chances of its being justified as fair use.
If there is no copyright claim by the original author then I don't see what the problem is./
Then you have no clue of what you're talking about. Many of the other posts in the thread have bad information as well though, so don't feel too badly about it.
For those in the United States, the definitive source would be the Library of Congress copyright web site. Since you're talking about code, you probably also want to read Circular 61, devoted to "Copyright Registration for Computer Programs".
For those outside the United States, the details change, but in most countries the basics remain the same. Specifically, the copyright laws in most countries follow the rules of the Berne convention. Of course, that's only the law itself -- enforcement varies much more widely. In some countries, it's hardly enforced at all, while in others (e.g. the US) there's almost no question the other laws are routinely broken to help enforcement even when there's little or no real evidence of copyright infringement having taken place at all (e.g. tens of thousands of RIAA cases).
He may have a mild point (certainly not worth +5) but really blows it on the second item. Completely wrong. Down you go.
Sorry, but you're simply wrong. It's true that DC tends to lock up the muscles, so it's more difficult (and sometimes impossible) to let go of the conductor. It's still considerably less dangerous though -- in particular, even though you can't let go of the DC line, there's still very little chance of it doing any real damage. In particular, AC carries a substantial risk of causing fibrillation, which DC doesn't.
In reality, however, your biggest risk is generally of burns. With DC, the rated voltage IS the voltage. With AC, you're normally looking at the RMS voltage of a sine wave, which means the peak voltage is approximately 1.414 (i.e. the square root of two) times a great. An arc (for example) can cause a burn quite easily within the time-frame at which the AC is close to it's peak, so the potential for such burning is roughly 1.414 times as great with AC as with DC.
Of course, this isn't truly a characteristic of AC vs. DC, but of sine waves -- in theory, with a perfect square wave, AC would be identical to DC in this regard. The most obvious problem with that, of course, is that a perfect square wave isn't even theoretically possible (it requires overtones going up to an infinite frequency) and the capacitance of a normal transmission line will tend to filter out higher frequency components, so even if you tried to transmit a square wave from the power station, you'd quickly end up with something extremely similar to a sine wave anyway (because a pure sine wave contains only the fundamental frequency, with no overtones at all). At that point, you're back to the peak being the square root of two times the RMS voltage.
For those looking on, the RMS voltage is the voltage necessary for AC power to have the same total amount of power as a DC voltage. With AC, the voltage swings from some peak, down to zero, to the peak in the other direction, back to zero and repeats. Since the voltage is less than the peak part of the time, you need to raise the voltage at its peak to make up for the amount of time it's less than the peak. With the perfect square wave mentioned above, there would be no such period of time -- the voltage would swing directly from one peak to the other, so the peak and RMS voltages are identical. With any real wave, however, the peak is always higher than the RMS -- and as mentioned earlier, with a sine wave factor by which it's higher is the square root of two.
A few, but not very many. The main one is that many power uses require DC in the end, so AC has to be rectified and filtered before it's used -- and in doing so, some power is lost. When/where you're using a lot of power in a relatively restricted area, that can make a meaningful difference. Automobiles, for one obvious example, mostly use 12V DC systems (nominally 12V -- really around 14V). Aircraft, for another example, mostly run on 48V DC (IIRC). Some data centers have also gone to having a single big power supply, and then piping DC around to the individual computers. I haven't measured it personally, but they claim this can cut power usage by around 30% in some cases.
Another difference is that getting shocked by DC tends to be slightly less dangerous than the same shock from AC. A 110V DC shock to bare (unbroken) skin is is quite mild feeling, where most people in the US have found (sometime or other) than 110V AC is fairly uncomfortable, though usually not particularly dangerous (i.e. for every person who dies of electrocution, an unknown but certainly large number of others are shocked with no real consequence beyond surprise and discomfort).
Slashdot Mirror
Of course they are -- in fact, it's unavoidable. Anything anybody does causes at least some change, and games are no exception to that.
This has two differences: 1) that you've written the game with some specific change(s) in mind, and 2) that the changes you had in mind fit the organizers' idea of social consciousness.
Even if, for example, GTA IV was written with the specific idea of changing people's attitudes, it probably wouldn't qualify for this show. My own experience has been that shows like this are largely self-contradictory: they claim it's about socially conscious games -- but they nearly automatically disqualify anything that's really fun as not being sufficiently socially conscious...
Without getting into details of MS products in particular, I think there's a strong possibility of exactly the opposite happening. Specifically, a product that's perceived as free and sufficient reduces or removes the motivation for anybody to compete, even if they could produce something that's a lot better and might even be substantially less expensive when all factors are taken into account.
You're absolutely right. This is why Novell Netware and Visicalc...oops I mean Lotus 1-2-3, continue to dominate the market to this day!
Intel's been doing that (to some degree) since the Pentium, and they increased it a lot in the Pentium Pro/Pentium II. It works reasonably well up to a point (modern chips typically execute an average of two instructions per clock cycle) but definitely has limits.
Compilers to automatically detect when instructions can be executed in parallel have been around for years. Cray had vectorizing compilers by the late 1970's, and within rather specific limits, they worked perfectly well. Just for example, if you wrote a loop like:
they'd break the loop down into four actual executions of a loop, each of which worked on 64 items in parallel. It had independent execution units, so at a given time it'd normally be loading one set of 64 items into one set of registers, executing multiplications on a second set of 64 items, and storing results from a third set of 64 registers.
That has a couple of problems though. First of all, if you're not careful, it's pretty easy to create loops with (apparent) dependencies from one iteration to the next, so the compiler can't parallelize the code. Second, this works well for vector processors, but probably not nearly so well for a large number of completely independent processors (which have higher communication overhead, meaning that starting up things to happen in parallel is more expensive).
If you're willing to provide the compiler with a little help, it can do quite a bit more, such as with MPI. The standard MPI interface is pretty low-level, but if you want to do the job in C++, Boost.MPI helps out quite a bit (cheap plug: if you want to know more, consider attending Boostcon '08).
Sure. In fact, VHDL is based (closely) on Ada, which allows pretty similar things. The relevant differences are less between the languages than how they're used. Ada that was written in the same style as most VHDL would have a high level of parallelism as well.
That's rarely done though, because designing hardware in VHDL (or Verilog, etc.) is expensive, largely because designing things this way is difficult. Virtually nobody's willing to put up with the long lead times and extremely high initial expense of such a design for software, unless it's doing something that really gains a tremendous amount from doing so.
Of course, that hasn't stopped people from trying. The Transputer was one early attempt. The Ambric is on the market now, and apparently sells pretty decently into a few specialized markets (e.g. video encoding/decoding) but I've never heard of anybody even advocating that it was a practical tool for a typical desktop computer.
There is no such company.
Microsoft originally designed Windows NT to be portable, and ported it to most of the popular architectures, including MIPS, PowerPC and the DEC Alpha (and probably SPARC, though it never made it to market). All of those have died, because they didn't sell well enough to stay on the market. Right now, Windows is available for the Itanium, but I certainly don't know anybody who's running it on one.
Intel has tried as well -- the Itanium is only the latest attempt at superseding the x86. In fact, the 8086 was originally designed specifically to be clumsy to program, in the hope that it would leave room for the iAPX432 to take over the market when it became available. Intel failed on both counts: the 432 as buggy as sin, and by the time it was available at all, the IBM PC had already taken the market so completely that Intel never produced a 432 that worked worth anything.
Of course, quite a few others have tried as well -- at one time, Sun pushed the SPARC as the architecture that would kill the x86. Sun still sells SPARC boxes, but they sell x86 servers as well.
From a slightly different viewpoint, the masses have already moved onto something else -- but gained very little from doing so. None of the current game consoles uses an x86. While the PS3 and Xbox 360 both have a lot of computing power, the Wii (with substantially less than either one) is what really gets a lot of people excited. The excitement isn't over the CPU though -- it's over the controllers.
The masses also buy a lot of CPUs in cell/portable phones. For this market, the ARM is the dominant architecture. It has excellent power consumption characteristics and such, which is nice, but in the end nobody really cares all that much that it's an ARM.
If, for example, Motorola 680x0 had dominated the market instead of the x86, life would be a bit nicer for those of us who still hack out a bit of assembly language now and then, but the reality is that most people would hardly notice or care. Apple has switched from the 680x0 to the PowerPC to the x86, and most users hardly batted an eye as they did so. To the typical user, CPU architecture is about as relevant as the brand of pipes used to bring water into their house.
A minor correction:
However, there is a minor weakness that should be pointed out, and could be corrected in the next edition. Specifically, the book includes a section on
That's not really new by itself. Just for an obvious example, most Flash ROM chips need a relatively high voltage for writing. Early Flash ROM chips used dual power supplies to support that, but most current Flash ROM chips use a single external power supply and an on-board DC-DC converter to produce the write voltage.
It's also not clear (at least to me) whether they're really scaling the supply voltage down to the point needed, or possibly scaling it up as needed. As noted above, scaling up has been common (at least for some kinds of chips) for quite a while. Scaling down isn't nearly as common, but I'm pretty sure some kinds of chips (for some reason, A->D converters come to mind) have done that as well.
Energy harvesting is mostly a matter of reducing the power usage to the point that it becomes practical. RFID tags (for one obvious example) are powered entirely by the transmitter that reads them. That is, to read one, you put the reader close to the tag. The tag has an antenna that picks up the radio signal from the reader, and uses it to charge a capacitor. The power from the capacitor is used to transmit a signal back to the reader.
Simply using heat to generate electricity is well known as well. Thermocouples, which generate electricity directly from a temperature difference have been known for a long time. Most electrical power plants start by producing heat, use that to boil water, then use the steam to run a turbine.
There's not enough in TFA to say for sure, but I'd guess rather the opposite. The main thing they mention is a lower power supply voltage. Power supply voltages have been dropping steadily for a long time. Once upon a time, the most common logic family was the 7400 series, which all used 5 volt power supplies. Somewhat later 3.3 volt CMOS logic was introduced. Most CPUs, memory, etc., now use somewhere between 1 and 2 volts.
For the most part, you get a trade-off between voltage and speed -- with a higher voltage, you can charge up a more reactive load more quickly, giving faster rise and fall times. That translates directly to higher bus speed.
At the same time, the power you use is the product of the voltage and the current, so as you raise the voltage you raise the power usage. Worse, the current you drive through a given impedance also rises linearly with the voltage -- so the power usage is proportional to the square of the voltage.
That (probably) explains to a large degree how/why they've reduced the power usage by a ration of 10:1 by reducing the voltage by a ratio of something like 4:1 (in theory, a 10:1 power reduction should imply a voltage reduction by the square root of 10, roughly 3.16).
In any case, however, nothing in the article really suggests that they've departed a great deal from the path everybody's been following for quite a while. Of course, they may have done something truly radical here -- but based on what they've said, that isn't necessarily the case.
Let's see. He asks that the visit be canceled. The visit gets canceled. Then he complains about the visit having been canceled.
This sounds like the guy's ready to complain no matter what happens.
Use the source Luke!
That's more or less the natural result of this being an amicus curiae brief rather than a brief directly on behalf of the defendant.
That's certainly one way to interpret what they've filed, but it's far from the only one. In any case, the position does not seem to be supported by the law, which specifically says that such an infringement requires an actual copy to an unauthorized individual, such as somebody else downloading the file from the shared directory, not just putting the file into the shared directory in the first place.
To make a long story short, you may be right about what the industry believes (or wants to believe), but even if you are it makes no real difference. This position does not appear to be in accord with the plain meaning of the law, or the positions taken by the courts in the past.
There's your fundamental mistake -- at least as far as I can see, he did not load the MP3s into a file sharing program. Rather, he:
1) loaded the MP3s onto his computer
2) completely separately installed a file sharing program
There seems to be no evidence at all that he really took any action to connect the two -- rather, the file sharing program, by default, shares the directory where he happened to put the files. He probably didn't even explicitly select that directory for the files -- it was probably selected by default as well.
He sounds to me a lot more careless than evil.
It would be equally valid to ask what makes you think you have any right to benefit from your work at all?
There doesn't seem to be anything in the Bible, Koran, etc., granting a divine right to benefit from your work. The US constitution does grant such a right. In doing so, it states that the reason for doing so is to promote progress, and specifically states that such rights shall be granted for only a limited time.
In other words, the exact document that gives the right (in the US) in the first place also places an explicit limit upon that right. As such, there seems to be far more reason to question why you think you can/could/should have an unlimited version of that right at all.
You are under no obligation to publish your work at all, whether the public finds it useful or not. The public has granted you a limited right to control over your work, and it's up to you to decide whether that right provides you with sufficient incentive to publish your work or not. If not, feel free to never publish the work at all. If so, feel free to do so. What's happened in the case of copyright, however, is that people published their work, and then get congress to change the law so they continued to benefit long after the original terms expired.
If you sell your work to somebody, what gives you a right to control how they use it at all? If I buy a table, or chair, or bed, etc., I pay for the object itself. If I decide to go into the business of selling tables, chairs, beds, etc., and sell ones just like the one I bought, I'm perfectly within my rights to do so. That's not theft by any stretch of the imagination. When I bought the original, I gained the right to use it as I saw fit -- including making copies of it if I saw fit to do so.
When something is truly stolen, that deprives the owner of their actual property. Making (for example) a copy of a song doesn't deprive the original owner of their copies of that song, therefore it is simply not theft at all.
Lawmakers, however, have long recognized that by providing you with rights beyond protection from actual theft they are likely to provide you with incentive to publish your work that would almost certainly otherwise be absent. In doing so, there has been a clear (and reasonably consistent) recognition of the fact that they're doing so for a specific reason, and therefore should limit those extra rights to only what's needed to achieve that specific purpose.
To make a long story short, the rights were granted by law only to achieve a specific purpose, and specifically for the benefit of the public. They are limited for precisely the same reasons, because doing so benefits the public. It's also worth noting that in reality, it is primarily the creators of original works that benefit from the limitations on copyright. For example, many of Disney's classic movies are based on existing stories such as Snow White and the Seven Dwarves, Cinderella, The Little Mermaid, Beauty and the Beast, and so on.
Two basic reasons. First of all, the basic overhead costs like packaging and shipping are basically fixed, regardless of the capacity of the hard drive. While they have little effect on the cost of a $200 item, they'd eat you alive trying to sell hard drives for $20.
The second reason is closely related: the cost of building a hard drive depends relatively little on its capacity. You can predict the cost of the drive fairly accurately based only on its form factor. Yes, as the capacity goes up things like the heads and the coatings on the platters change, but they don't change the cost all that much. Obviously when you put more platters in a drive, the cost goes up, but within the typical 1/3 ht. form factor, you don't have room for enough platters to cause anything like an order of magnitude difference in cost.
The rule is really very simple: standard hard drives (i.e. excluding things like micro-drives) really have a nearly constant price of roughly $250/pound. Most of what's changed over time has been the amount of data you can store per pound.
I guess I should have been a bit more clear. When the plant is still operating normally, so you can continue to run steam through it, it's absolutely true that cooling down only takes a few days. As you run steam through, it pulls out a lot of heat relatively quickly.
I was talking about a situation where you have a problem sufficient that you can't run steam through any more. In a case like this, cooling down takes drastically longer -- for normal use you (of course) have the hot parts of the plant heavily insulated to retain the heat as well as possible. I just spent a bit of time re-reading accounts of the incidents at Three Mile Island and Chernobyl, but I haven't been able to find any that say exactly how long it took to cool down the steam plant to the point that human entry was possible. The Three Mile Island accident took place in late March of 1979, and it was July of 1980 when the first person re-entered the reactor chamber (everybody reports on that!) but my recollection from the time is that it was around May or so before the steam area was reentered -- though I'll openly admit I'm going from memory, and it's obviously been quite a long time. Of course, it's also possible that reentry into some parts of the plant were delayed longer than strictly necessary, simply due to the other concerns at the time.
Taking a look at some actual facts doesn't seem to support your contention, at least as to expense. I suspect the danger level (especially if you count birds and such) is much higher for wind generation as well.
Don't get me wrong: I'm not against wind turbines -- but I think you're overstating what are really rather modest advantages, at least at the present time.
As several posts (including one of mine) have pointed out, fission can be used for quite a while (even if you don't take breeder reactors into account). Converting a fission plant to a fusion plant would be interesting. Basically, the reactor itself would almost certainly be scrapped entirely. The turbines and generators, OTOH, wouldn't generally care whether the steam was produced by fusion or fission, so they could probably remain more or less intact.
Interestingly, when/if you actually look carefully at the history of accidents (and near-accidents) in nuclear power plants, most of the problems are surprisingly mundane. In fact, it looks like a lot of the problems are basically mechanical -- things like building a steam valve that simply opens and closes dependably for years at a time, even though the steam involved is at high pressure and temperature (e.g. ~300 degrees C and 2000+ PSI). Quite a bit of research has been done into temperatures and pressures of primary coolants (near the bottom of the page).
Even if a repair is strictly in the steam part of the plant (where nuclear radiation isn't a problem) it can take months to cool hundreds of tons of steel, concrete, etc., down from its normal operating temperature to the point that a person can enter and work on something. This makes the cost of repairs so high that the system must be engineered to run for years (preferably decades) at a time without them.
As closely as I can figure it, there are about 11_515_262_616_000 metric tons of Uranium-235 in the earth's crust.
.099% of that. Uranium occurs at a rate of about
2.7 milligrams per kilogram in the crust, and about 0.7204% of that is Uranium-235.
The numbers work out as follows: The mass of the earth is about 5.98e24 kilograms. The crust is about
Some of that would undoubtedly take more energy to mine, purify and enrich to usable levels than it would produce as output -- but even if only one percent is usable, it still works out to quite a large energy supply. Enrichment isn't necessarily needed -- but if you don't enrich the Uranium, you typically also have to moderate your reactor with deuterium, and it takes a fair amount of energy to purify deuterium from normal water as well. In any case, once you've purified the Uranium, enrichment is roughly a fixed cost regardless of the original source.
There's also Uranium in sea water, though the rate is quite low (3.2 micrograms per liter). That might be a practical supply as well, but I don't know enough about how difficult it is to purify from sea water to be certain. My immediate guess is that if the only alternatives were things like solar or wind power, somebody could figure out a practical way to do it.
I doubt it. Fair use means convincing a court that the use you're making of the material is really fair. In many cases, that means writing something that's sufficiently different that the court believes you're not really competing directly with the original author -- for example, a book review that quotes a few lines from a book isn't likely to be used as a substitute for buying the original story. Quoting a few particularly telling lines can give a good idea of the book's topic and style, so doing so will generally be considered fair use. This case seems to be almost entirely different however -- it's not writing something new or original about that code, but simply using it as it was originally intended. Even when courts do look at the amount copied, they rarely look exclusively at just the raw amount involved -- they frequently look at both the percentage of the original that was copied, and the percentage that the copied material constitutes of the final work in which it is copied. If I copy 200 lines from War and Peace, it would generally be easier to justify than if the 200 lines being copied were virtually 100% of the original (which sounds like it might easily be the case here). Likewise, if I write a long book and copy one-liners from here and there as titles to chapters and such, it's easier to justify than if all I've done is paste in a single large quote from somewhere, and that's all I'm publishing.
Even though I doubt this would qualify as fair use, publishing exactly the same code under other circumstances might well be fair use. For example, if I was writing a book on coding style, and included all 200 lines of this snippet as an example, and wrote a line-by-line analysis of how it was written, that would almost certainly improve the chances of its being justified as fair use.
Then you have no clue of what you're talking about. Many of the other posts in the thread have bad information as well though, so don't feel too badly about it.
For those in the United States, the definitive source would be the Library of Congress copyright web site. Since you're talking about code, you probably also want to read Circular 61, devoted to "Copyright Registration for Computer Programs".
For those outside the United States, the details change, but in most countries the basics remain the same. Specifically, the copyright laws in most countries follow the rules of the Berne convention. Of course, that's only the law itself -- enforcement varies much more widely. In some countries, it's hardly enforced at all, while in others (e.g. the US) there's almost no question the other laws are routinely broken to help enforcement even when there's little or no real evidence of copyright infringement having taken place at all (e.g. tens of thousands of RIAA cases).
Sorry, but you're simply wrong. It's true that DC tends to lock up the muscles, so it's more difficult (and sometimes impossible) to let go of the conductor. It's still considerably less dangerous though -- in particular, even though you can't let go of the DC line, there's still very little chance of it doing any real damage. In particular, AC carries a substantial risk of causing fibrillation, which DC doesn't.
In reality, however, your biggest risk is generally of burns. With DC, the rated voltage IS the voltage. With AC, you're normally looking at the RMS voltage of a sine wave, which means the peak voltage is approximately 1.414 (i.e. the square root of two) times a great. An arc (for example) can cause a burn quite easily within the time-frame at which the AC is close to it's peak, so the potential for such burning is roughly 1.414 times as great with AC as with DC.
Of course, this isn't truly a characteristic of AC vs. DC, but of sine waves -- in theory, with a perfect square wave, AC would be identical to DC in this regard. The most obvious problem with that, of course, is that a perfect square wave isn't even theoretically possible (it requires overtones going up to an infinite frequency) and the capacitance of a normal transmission line will tend to filter out higher frequency components, so even if you tried to transmit a square wave from the power station, you'd quickly end up with something extremely similar to a sine wave anyway (because a pure sine wave contains only the fundamental frequency, with no overtones at all). At that point, you're back to the peak being the square root of two times the RMS voltage.
For those looking on, the RMS voltage is the voltage necessary for AC power to have the same total amount of power as a DC voltage. With AC, the voltage swings from some peak, down to zero, to the peak in the other direction, back to zero and repeats. Since the voltage is less than the peak part of the time, you need to raise the voltage at its peak to make up for the amount of time it's less than the peak. With the perfect square wave mentioned above, there would be no such period of time -- the voltage would swing directly from one peak to the other, so the peak and RMS voltages are identical. With any real wave, however, the peak is always higher than the RMS -- and as mentioned earlier, with a sine wave factor by which it's higher is the square root of two.
A few, but not very many. The main one is that many power uses require DC in the end, so AC has to be rectified and filtered before it's used -- and in doing so, some power is lost. When/where you're using a lot of power in a relatively restricted area, that can make a meaningful difference. Automobiles, for one obvious example, mostly use 12V DC systems (nominally 12V -- really around 14V). Aircraft, for another example, mostly run on 48V DC (IIRC). Some data centers have also gone to having a single big power supply, and then piping DC around to the individual computers. I haven't measured it personally, but they claim this can cut power usage by around 30% in some cases.
Another difference is that getting shocked by DC tends to be slightly less dangerous than the same shock from AC. A 110V DC shock to bare (unbroken) skin is is quite mild feeling, where most people in the US have found (sometime or other) than 110V AC is fairly uncomfortable, though usually not particularly dangerous (i.e. for every person who dies of electrocution, an unknown but certainly large number of others are shocked with no real consequence beyond surprise and discomfort).