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For some reason, the brighter the still image presented to the viewer ... the shorter the persistence of vision. So, bright pictures require more frequent repetition. If the space between pictures is longer than the period of persistence of vision -- then the image flickers. Large bright theater projectors avoid this problem by placing rotating shutters in front of the image in order to increase the repetition rate by a factor of 2 (to 48) or three (to 72) without changing the actual images.

I think you are referring to the Virtual Retinal Displays (VRDs) that were being developed at the Univ of Washington's Human Interface Technology Lab.

A company called Microvision has been making these sorts of displays for military applications, but they are now trying to bring the technology to more "mainstream" applications.

I think you are referring to the Virtual Retinal Displays (VRDs) that were being developed at the Univ of Washington's Human Interface Technology Lab.

A company called Microvision has been making these sorts of displays for military applications, but they are now trying to bring the technology to more "mainstream" applications.

I was one of the main developers of a portal here at the University of Washington, MyUW. We did it all ourselves, although at the time we did look at companies like Campus Pipeline and another product called Blackboard, at least to see what they included. Even if we would have wanted to use these products, it's dubious we could easily do so, due to the wide dispersal of the interesting data here at the UW: one group has the main Student database, with grades, schedules, etc. The Housing and Food Services department has a separate database with dorm info. Financial Aid is elsewhere, etc. I got the feeling that many of the campuses that use services such as this are small enough so that one small group of people is in charge of nearly all the data (as well as probably running the e-mail system and web servers), and thus it's pretty easy for Campus Pipeline or whoever to come in and take over.

After we were pretty much done with version 1.0 of MyUW, another group of schools started a project dedicated to producing a collaborative University Portal Framework. It's called the JA-SIG Portal Framework Project (the J means it's being done in Java), and it's about the closest thing to an open-source portal project I've seen. The license is hard to find, and I think they're still working on it, but the last time I looked, it bore an uncanny resemblance to the Mozilla Public License.

One area where these things are really taking off is Alumni Associations. Companies basically come in, wave some money, offer 'lifetime e-mail' for members, and then set up a 'portal' that directs the members to cool shopping, travel, credit card, and other (for the company) lucrative offers. Now, it's not as if Alumni Associations were ever adverse to such marketing deals, but this is a whole other level, with essentially a 'lifetime' commitment on the part of the Alumni Association, as opposed to the once-a-year 'buy our life insurance' type of offers that were standard in the '80s.

This is the same as my cue cat. And here I thought I was going to do well by the play by play of the circuit!!
I got delayed because from the description it became apparent that we are talking about two different cuecat internals.
Post #43 talks about it being a toshiba CPU. Specifically, this cpu belongs to TLCS 870 family of microcontrollers. It is register rich and C code compiles to it very easily. You use this kind of core if you want to do a lot of math on your data (so yeah, you could do a linux port!)

My Cuecat, like the one pictured in the above link, has a Hyundai 90c54 which is an 8051 knock off. Everybody and their dogs makes a souped up 8051 which this probably is. The memory is 8k byte wide (64k) which is a lot for a little microntroller. So, they must write their code in C, and do alot of processing on what it reads. My guess is that they switched to the 8051 core for cost reasons, as there is a bit of loss lead taking place. While the first response of some would be "I would have used a pic" I have found that in a manufacturing enviroment that 8051 can be more cost effective, just because there are so many of them available. Pics are good for small scale manufacturing.

Notice that the inside of the cuecat is black, and the top part of the housing has some black carboard material, black plastic piece cover, and the sensor had black tape around it. That's alot of effort to keep out extraneous light. They probably don't want _any_ extraneous reads (work first time). Nice touch to improve product acceptance.

The chip next to the photodiode is probably an OTA, (i.e. transconductance current amplifier), and the opamp next to it probably is used as an amplifier/comparator combination that feeds into the microcontroller.

From the description, it looks like that optics have been simplified also to remove the IR module and replace it with a photodiode/led light pipe combination. Again, cheaper to make. Notice that the photodiode sits an inch hehind a lens, and the diode has a pinhole covering. I think that achieves a camera obscura effect that probably means that it is very sensitive, can read at different angles and no miss reads. So it can probably read other barcodes where other readers might fail. Very cost effective design. I think that this optical systen is probably covered by patent "4,816,659 Bar code reader head".

Metrologic has three patents on barcode input going to browsers and the World Wide Web. So I would worry about them before I would worry about Cuecat.

On the serial id number, there has to be a way to program the device once it is assembled, so that means that it is probably done with a special sequence through the connector. Maybe even by typing in a special code!. So you 31337 types can get busy. Myself, I'd rather think about a more cost effective/easier to manufacture design. It is easier to design something anyway than to reverse engineer the whole thing. A great place to start is h ere, thanks to Mr. 1010011010 and his post #52 below :-)). I would use a pic in this, because it would be quick and easy. I also looked through the expired patents and got some good ideas how this design could be simplified.

The Cuecat does reflect alot of engineering that results in a robust design to achieve high performance. This is probably necessary to ensure consumer acceptance. I do not think it is the most efficient design though. For somebody who wants to make a cheap barcode reader for their own CD/book inventory, there are cheaper and easier ways to make their own, and achieve the same result (outside of obtaining more Cuecats/other bar code readers).

The website h ere describes how to make your own RS232-output barcode scanner.



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more info can be found here.

DeCSS can be obtained, for example, here, but there is a list of mirrors here.

I don't mind if what I have written is illegal. I have freedom of speech.

A request, if someone is thinking of writing their own. The old catalog system at the University of Washington Libraries allowed searching on multiple fields. For example, you could combine author "clark" with keyword "trail" to find Lewis & Clark related materials without scrolling past A. Clark's Acrylic Plastic Spherical Pressure Hull For Continental Shelf Depths.

Unfortunately, this functionality is disabled in their new catalog (html or telnet). This is a simple task for any database, but I can't remember a library I've visited in years that allows it.

The idea of a nitrogen powered car is hardly new, the University of Washington has been developing the CryoCar for a the past 3+ years.

From the LN 2000 car page.

The process to manufacture liquid nitrogen in large quantities can be environmentally very friendly, even if fossil fuels are used to generate the electric power required. The exhaust gases produced by burning fossil fuels in a power plant contain not only carbon dioxide and gaseous pollutants, but also all the nitrogen from the air used in the combustion. By feeding these exhaust gases to the nitrogen liquefaction plant, the carbon dioxide and other undesirable products of combustion can be condensed and separated in the process of chilling the nitrogen, and thus no pollutants need be released to the atmosphere by the power plant. The sequestered carbon dioxide and pollutants could be injected into depleted gas and oil wells, deep mine shafts, deep ocean subduction zones, and other repositories from which they will not diffuse back into the atmosphere, or they could be chemically processed into useful or inert substances. Consequently, the implementation of a large fleet of liquid nitrogen vehicles could have much greater environmental benefits than just reducing urban air pollution as desired by current zero-emission vehicle mandates.

When can we start?

There is another project at the University of Washington called LN2000, and after a quick glance at the website it appears to be even further along than the UNT project. Their test vehicle is a converted 1984 Grumman-Olson Kubvan mail delivery van and they also have a website.

This isn't exactly anything new... The University of Washington has been researching this for a while and has a working (albeit inefficient) model of a LN-powered car...

Here's a link: LN 2000

One of John Cramer's Alternate View columns is about this topic both generally (what are the problems, who makes the lists and what is the public perception of science's unsolved problems) and specifically (seven unsolved problems that he thinks are important). It is interesting to note that there are overlaps between many of these lists.

One problem that Cramer mentions that no one else seems to, however, is the causality problem. I often wonder if science as a paradigm can even deal with this sort of problem as causality is implicit in experimentation.

One of John Cramer's Alternate View columns is about this topic both generally (what are the problems, who makes the lists and what is the public perception of science's unsolved problems) and specifically (seven unsolved problems that he thinks are important). It is interesting to note that there are overlaps between many of these lists.

One problem that Cramer mentions that no one else seems to, however, is the causality problem. I often wonder if science as a paradigm can even deal with this sort of problem as causality is implicit in experimentation.

I know its extremely off topic, but why are two copies of this story appearing for me every time I log in?

Now, for the on-topic: there had better be a Thief III, and it had better NOT have anything remotely in common with that black void of crap called Diakatana!!!

I'm sorry to see looking glass go. . .didn't they also do Flight Unlimited? Pretty impressive engine when it first came out!

http://students.washington.edu/steve0/

yeah, I bet the Artist Formerly Known as Prince did it all himself too--he sure can "C the Future".

I know its 'artsy' typing, but someone ought to do him a favor and teach him the keyboard shortcut for spellcheck in Word with a big stick.



http://students.washington.edu/steve0/

Heidi Moeller: [...] Is the MS-DOS prompt still in Millennium, or has it been deleted?

Alan Sohn: That's a good question. As you might or might not have heard,
Windows Millennium will not include the ability to be able to boot up to a MS-DOS prompt from the hard disk . We've included some of the real-mode functionality from within Windows Millennium, to allow for better stability and performance , and even eliminate a lot of the troubleshooting aspects . However, you still will be able to go out to a MS-DOS virtual machine, or a virtual MS-DOS prompt within Windows, just like you could in previous versions. Basically the limitation here will be the fact that you can't boot to a Start menu, and then choose command prompt as one of the options.

If you need to boot to a command prompt, you can still do so through the emergency startup disk. That will still be an option, to be able to create one within Control Panel Add/Remove Programs, or during setup. We'll also give you the option to create a startup disk at that time as well.

. . .is Carmack's EXCELLENT point on how the X-box--if it IS the 'future of gaming'--will force games to be written around propietary NVidia chips. Does this disturb anyone else? I have nothing against Nvidia (other than the usual), but I think that in the extremely limited graphics card-technology marketplace, this will slowly stamp out 3dfx (who're half dead already) and any startups.

'Course, from a programmer's perspective, maybe its good news--no more diverging standards, huh? But I'll miss debating which is the hotter card during class!

-s

http://students.washington.edu/steve0/

Steve Jobs is a showman first, CEO second. Nothing makes him happier than suspense. Someone robbed his thunder, and as a result he went out for blood.

People copy images all the time in 'sneak peeks.' The whole thing reminded me of the fake 'code' names that movies sometimes give themselves while in production to protect themselves from leaks (for any fellow star wars geeks here, "Blue Harvest" was the codename for Return of the Jedi while it was being made), or car disguises when test vehicles are being driven. Its all about drama.

'Course, once Jobs went on the warpath, his lawyers could probably find something suable with everyone. Bah.

-s

http://students.washington.edu/steve0/

Very true, but you can do a LOT with lines, text, and area fills. And the files they make are SMALL. Look at Flash--if you're careful, you can make a complete website or fairly complex web app costing about 60k max. (example here, ~68K for a LOT of drawn stuff) It sure as heck will be nice to have scalable vector graphics without having to rely on a plugin.

On an off-topic note, this having been in the works for a while, I can understand Macromedia's moving towards increased interactability with Flash 5.

-s

http://students.washington.edu/steve0/

Very true, but you can do a LOT with lines, text, and area fills. And the files they make are SMALL. Look at Flash--if you're careful, you can make a complete website or fairly complex web app costing about 60k max. (example here, ~68K for a LOT of drawn stuff) It sure as heck will be nice to have scalable vector graphics without having to rely on a plugin.

On an off-topic note, this having been in the works for a while, I can understand Macromedia's moving towards increased interactability with Flash 5.

-s

http://students.washington.edu/steve0/

Well hey, this is kinda like the law against telemarketers calling you after tell them exactly to "take me off your list." I read somewhere that if they call again you can sue them. (more info on this pertaining to telemarketing/junk email here. . .interesting read if you havent seen it already)

The hairy line between advertising and harrassment keeps getting tugged from one side to the other by the courts, regardless of the tangled mess of precedent. Meanwhile, we still get spam and probably always will, 'specially with more people checking their email and letting the voice mail be.

-S

http://students.washington.edu/steve0/

Alright,...the coolest page from the whole damn thing, from the Escherization project.

Alright,...the coolest page from the whole damn thing, from the Escherization project.

You all might be interested to know that during the paper session for the project Escherization, an image of the penguin came up and the graphics audience of more than a thousand people went up in applause. The results of his research would make a great desktop background for a penguin head.

The defensive posture of many of the respondents to Jon's article is quite instructive. Indeed, his point "...to be ignorant of the past is to be defenseless against the future..." is bolstered by the feverish reactions of a very priviledged sector of the world's population (I myself am among them).

One respondent asserted how hard we geeks have worked to gain our technical expertise. "Tough Noogies" he says to those who lack an understanding such as his, because they are obviously lazy or stupid if they don't understand email encryption programs.

Most of my tech friends are white, male, middle-class 20-somethings, who benefitted from access to a CS department in some university, parents who paid for their first Commodore, and life in an advanced capitalist economy which values their tech skills. All too often they are unaware of the blood and sweat from which they directly benefit. Arrogantly, they talk of how hard they worked to get where they are.

I don't agree with Jon's praise of individualism, as it ignores the weight carried by those who toiled in some sweatshop to assemble everything from the boards in your PC to the shirt on your back to the coffee your drinking. There is an egregious arrogance in the tech community about the historical role of colonial subjugation, military brutality, and fierce labor exploitation in bringing us to our current state of technical comfort.

What is needed in the opensource community is not a focus on more individualism, but rather an emphasis on how our feelings about freedom of speech and information are directly related to realities of the global economy. What Jon described as a handful of protestors in Seattle was estimated by some to be almost 50,000 mostly peaceful demostrators who were taking to the streets in protest of what the corporations are doing to the planet.

Those of you concerned about freedom and democracy have a lot in common with the people protesting in Seattle, DC and now Philadelphia.

My appologies for the previous empty post...

The University of Washington CSE department worked on a distributed memory system. The idea was to efficiently use all the excess fragments of ram across a cluster of high performance machines on a high performance network. Called GMS
http://www.cs.washington.edu/homes/lev y/gms/

but what does Ethereal do that would astound network troubleshooters?

Provides a GUI packet capture and analysis program for UNIX? GUI sniffers are something Windows and Mac folk have been used to for a while, but if the network administrators had only seen tty-oriented tools such as tcpdump or snoop, Ethereal might've been a surprise.

Ethereal isn't the only GUI packet capture and analysis program for UNIX; there's also Knetdump (given the first letter, nobody gets a prize for guessing which GUI toolkit and desktop environment it uses :-)), and there's also tcpview, a Motif application based on an old version of tcpdump.

FYI, wavlet compression is a method that uses fractals to compress an image.

No: Wavelet image compression uses wavelets -- not fractals -- to compress images. They both look at data at multiple scales, however. Most "fractal" hype comes from the fact that they're "cool" and not from any real application outside of synthetic textures.

If you want to learn about wavelets, I'd advise looking up the Haar basis (the simplest wavelet basis to use) on a 1D scanline of an image. Better yet, check out Stollnitz's excellent and understandable Wavelets For Ccomputer Graphics: A Primer.

No, I meant Nick Diamos.

try a search for Fletcher Pratt's books

And this is supposed to indicate what? Even if Pratt wrote about the quote in one of his fictions, it's doubtful that the actual text would be found online. The only reference I could find attributing this to Napoleon was on Jerry Pournelle's page, where a fan incorrectly referred to Nick Daimos as Nick Dalius. Jerry was unable to give a definitive source for attributing the quote to Napoleon, although he insisted it was correct, and suggested it was the kind of incident favored by Fletcher Pratt. The coincidence of confusing Nick Diamos name and references to Pratt suggest that this was your source as well. Perhaps you should do a bit more research, Private Wrong-fact.

How does this compare with the other ideas for traceback, one of which is at http://www.cs.washington.e du/homes/savage/traceback.html?

This paper has some good ideas...

It does raise the bar, so the next steps in the cat&mouse game include ever-more-diffuse distributed attacks to avoid more ever-more-watchful intrusion detection and traceback mechanisms. Is that a bad thing? No -- it is a good thing to make successull attacks more challenging.

A little more background reading:

Stefan Savage, Practical Network Support for IP Traceback a technique for tracing, but requires a little packet marking/mangling which makes it unlikely to be adopted. Clever, though, I'm sure some of the ideas will fold into itrace.

Robert Stone, CenterTrack: An IP Overlay Network for Tracking DoS Floods A tool for ISPs to build monitoring networks without making every component cooperate. Hmmm... I wonder if Carnivore has remote tunnels built in?

Other efforts in traceback involve perturbing the source of floods (e.g. by hop-by-hop reverse flooding) and watching the statistical properties of the flood at each step.

When the occassional neutrino interacts with a water molecule, they use calorimetry to measure its energy and thus deduce its mass. Now if this sounds like a very imprecise measurement method, it is.

That would be pretty imprecise, given that you're dealing with abandoned mines filled with water or the Pacific ocean. Is that really how they do it, though? I know neutrino detection is typically done by light sensor arrays picking up Cerenkov radiation from neutrinos hitting the water (example). Maybe the mass is calculated differently, though.

It wasn't quite twice as many, but there were definitely more. See more info at http://faculty.washington.edu/chudler/ ein.html

Oh for chrissakes, what is this tripe?

Oh yeah, I remember: it's called Propaganda!

I spot Name-Calling, Glittering Generalities, Transfer, Plain Folks appeals (if the Plain Folks are geeks), Bandwagon and a bit of the old Unwarranted Extrapolation.

I can stretch and call Testimonial and Fear as well. There are few solid conclusions to be had but I can argue for Bad Logic in a couple spots.

I don't spot Euphemisms, but then again there are no negatives presented about Jon's point of view so I'm not surprised.

Do we really *need* propaganda on Slashdot?

I also work with Win 98/NT/2000, linux, and mac OS boxes, and here's my .02 on the matter: they all are GREAT for different things.

At work (I work for the Univ. of Wash), I do a lot of digital video production--i.e. capture, compressing, editing, yadda yadda. For this, the Mac is unbeaten in my mind. Hell, the other day I was mocking a friend of mine for wanting a DV iMac. How stupid, I thought then, was a machine like that? Then we got one to check out. It a)ran out of the box, b)had firewire, and c)within the first hour of its operating life allowed me to capture, edit, and compress a short movie. Meanwhile, the G4's haul ass on all of the above. Final Cut Pro 1.2 is a DV suite dream package.

Meanwhile, at home I have my win98 box. I do a lot of gaming, web browsing, and general messing around. Its stable (gasp!), I know it in and out, and everything in it, no matter how exotic, has drivers. 2000 just ain't there yet.

Finally, I do have a linux box as well. I use this primarily for perl coding, openGL hacking, and general experimentation. I'm no *nix genius, but I can move around just fine and have really grown to like it as a dev box. No more AIX UNIX telnet windows for me--Linux (I run SuSE) works great as a dev environment.

There ya have it. Apple machines look sleek, and can make sleek-looking things. The closed system works great (usually) when allowing Apple to release non-conflicting hardware. . . Hence the DV iMac being so impressive (despite being purple. . .UGH). Win98 is the workhorse family OS that everyone loves to hate, but it gets the job done--and has tons of support. And Linux is a nice alternative for development. I'd buy one of each.

S

http://students.washington.edu/steve0/
steve0@u.washington.edu

disks, tape, cds... they all have a relatively short lifespan. picture storing data in mice, just feed them and keep them warm. ev en if th e parents die the children will have the artificial chromosomes... (that is unless they recombine, in which case all of your documents or whatever are worthless....)

It's not like splicing is anything new - hell we've been making corn that poisons butterflys for a while now - it's not new. Why is this news? What is the nature of the chromosome, is that what makes it so special? What does it do? Anything?

1. With the "Plasma bottle", how big and how efficient is this magnetic sail? I thought the whole point of a physical sail is that you didn't have to drag along a power supply. Needing to sustain plasma seems to defeat the purpose.

   I'm not an expert on this. It's called Mini-Magnetospheric Plasma Propulsion (M2P2) and they claim solar panels and about 3kW are enough to sustain it.

2. How much solar wind makes it out past Mars?

   Well...all of it. There isn't anything that "absorbs" the solar wind (except obvious things like planets). The solar wind ends at the heliopause where is where the interstellar medium takes over. The heliopause doesn't happen until well past Pluto, the Voyager and Pioneer probes will pass through it soon, and scientists are eager to see if they send back any interesting data about it.

3. Hitting even a large sail with a ground based laser from thousands or millions of miles away seems like a hell of a shot. Would the atmosphere throw off the aim? Can it be compensated for like the new telescopes do?

   I haven't run this calculation, but yes, atmospheric distortion would be a problem, as would diffraction (at millions of miles, diffraction effects from the opening end of the laser can be large!) Compensating for atmospheric distortion may be possible. Extremely precise aiming devices would be required. It would also be a given that a large portion of your laser would miss the craft entirely. But even if 1% of the laser's power hits the craft, I'd guess that it's still cheaper than launching an equivalent power source.

--Bob

It did some things well, but overall I think it was about twice as long as it needed to be. Still, for a couple of guys with a camera and a lot of free time, I certainly can't claim to have done any better. . .Cut the whole pond/duck/narration sequence.

Neo singing '99 bottles of beer on the wall' was hilarious!

-S

http://students.washington.edu/steve0/
steve0@u.washington.edu

And how many other people here programmed a 4004? I found one in a music-tone guitar, ripped it out, and played with it. It was obsolete then, so they kept making them for quite awhile.

Oh, and as to the fact that the Commie 64 didn't have a Z80 - oops. I mentally thought to myself as I was typing: "It had a 6502 (like my trusty Apple ][+), and a Z80, and people are going to complain that it didn't have a Z80 because it had two CPUs".

It was the Commodore 128 that had a Z80 for CP/M mode. Both the 64 and 128 had 6502s as their main processor.

--
Evan

x86 gets a big boost because of register allocation. All that ugly spill code produced because of the register-limited architecture gets translated into register moves (or eliminated entirely). Unless code for a PPC, MIPS etc. was compiled assuming a lot more than 32 register (which it can't, due to the instruction format), there won't be much gain here.

Unless Transmeta adds partial evaluation/specialization a la DyC or Tempo, I don't think the benefit of code morphing on, say, a PPC will overcome the cost. I suppose they could do something like Dynamo and implement a software trace cache.

One interesting avenue of research would be to compile to a virtual ISA that included lots of registers and other fancy hardware structures the compiler could use. Taking advantage of new compiler innovations would then be a matter of designing a new ISA and writing the code morpher. Not having to re-do the silicon would be a big savings.

--

Schridonger's cat will be mightily relieved to hear that information does not require an observer. However, quantum physics (up to this point) would seem to differ.

That makes 3 observers, by my count. The reader, the protein processor, and the blue hair generator.

The Mandelbrot Set, for example, does not depend on who looks at it, to be a fractal. THAT information is truly independent.

One thing that Ars fails to mention is that Dynamo only achieves performance at or below todays very advanced profiling compilers. Look at the graphs in the short form of the Dynamo paper: Dynamo Paper(short)

Dynamo also ignores a very important aspect of dynamic optimization/translation; the values of variables through each execution of the trace cache (i.e. exploiting common values of loop counters, function parameters, etc). A lot of researchers feel that this is the future of dynamic recompilation/optimization.

For a look at something more atune to value specific optimizations look at DyC

There are some links there to other dynamic compilation/translation sites too.

Don't forget that the research in this field is very new. There are countless possibilities to use runtime information to make a program go faster. People are trying to discover quick techniques for capturing this info and cheap, beneficial optimizations/transformations to apply.

I really don't care for their choices at all. A lot of them are more like general approaches than algorthms, and I'm not at all sure they are the most influential. I think they are supposed to be "the cleverest of the common fancy methods"

Simple algorithms for common problems are much more widely used, and have far more impact and influence, but try telling *them* that!

I hope these links help. (Warning: many are technical) If anyone has personal favorites that are less dry than many of these, please post!.

10. 1987: Fast Multipole Method. A breakthrough in dealing with the complexity of n-body calculations, applied in problems ranging from celestial mechanics to protein folding. [Overview] [A math/visual approach]

9. 1977: Integer Relation Detection. A fast method for spotting simple equations satisfied by collections of seemingly unrelated numbers. [Nice article with links]

8. 1965: Fast Fourier Transform. Perhaps the most ubiquitous algorithm in use today, it breaks down waveforms (like sound) into periodic components. Everyone knows this one (or should) [Part II of my personal favorite FFT and wavelet tutorial]

7. 1962: Quicksort Algorithms for Sorting. For the efficient handling of large databases. [Definition][Basic Method][Mathworld][More technical explanation][A lecture with animations and simulations]

6. 1959: QR Algorithm for Computing Eigenvalues. Another crucial matrix operation made swift and practical. [Math] [Algorithm

5. 1957: The Fortran Optimizing Compiler. Turns high-level code into efficient computer-readable code. (pretty much self-explanatory) [History and lots of info]

4. 1951: The Decompositional Approach to Matrix Computations. A suite of techniques for numerical linear algebra. [matrix decomposition theorem] [Strategies]

3. 1950: Krylov Subspace Iteration Method. A technique for rapidly solving the linear equations that abound in scientific computation. [History] [various Krylov subspace iterative methods]

2. 1947: Simplex Method for Linear Programming. An elegant solution to a common problem in planning and decision-making. [English} [Explanation with Java simulator] [An interactive teaching tool

1. 1946: The Metropolis Algorithm for Monte Carlo. Through the use of random processes, this algorithm offers an efficient way to stumble toward answers to problems that are too complicated to solve exactly. [English] [Code and Math] [Math explained]

Yup, as a not-so-proud player of the demo, John Romero can spend the rest of my life washing my car. I might even tip him a quarter if he waxes.

Here's a hilarious and well-written review of the game that hits it right on the nose: Mo' Diakatana!

-S

http://students.washington.edu/steve0/
steve0@u.washington.edu

My apologies to Stephen Hawking for stealing the title (as best I remember it) of a chapter of "A Brief History of Time".

IAAPS (I Am A Physics Student, though somewhat rusty at the moment ;-)

Black holes can shrink (this is not to say they must shrink). While it may seem impossible, since matter and energy can not escape the event horizon of a black hole, black holes do radiate energy. Some other law of physics (pertaining to black body radiation, IIRC) requires that black holes radiate a certain minimum amount of energy, causing Hawking (and others) to ponder how this could be. Quantum mechanics provides a solution.

Space, even a perfect vacuum, is not devoid of matter. Although a perfect vacuum has an average energy of zero, this is only an average. Quantum mechanics allows for the spontaneous creation of "virtual" particle-antiparticle pairs, which quickly annihilate each other (virtual because they are annihilated before they ever interact with other matter). I forget the details, but the more energy such a pair has, the shorter the amount of time it can exist for--there's a Planck constant in there somewhere :-)

The trick is that near a black hole, sometimes these particle pairs sap energy from the black hole, and at least one of the particles becomes "real". You could imagine the other particle falls into the hole or something...

As for the article about Yilmaz's version of General Relativity (which predicts the non-existance of black holes), I don't yet know enough to criticize his General Relativity on the basis of the mathematics or theoretical physics. AFAIK, most of the "observations" of black holes have simply been of the motion of stars perturbed by massive, relatively dark objects, or of radiation thrown from the disk of material spiraling into a massive black hole candidate. I don't see why a small, massive (non-black hole) object as predicted by Yilmaz couldn't have been responsible for all these effects.

Do I think Yilmaz is right? Probably not, but it would be pretty damn cool if he is. I admire the guts of physicists who do "monkey wrench physics", and dare to challenge the established theories.

Please don't flame me if I've blown some of the details; I haven't done a physics course for over a year (I've been working on the comp sci half of my degree). I would appreciate any corrections or additions, though. I hope there are lots of other physics geeks on /. who appreciate the occasional change of pace from computer topics.

Many of you mentioned a recent case about Julia Roberts vs. a 'cybersquatter'. . . This is yet isn't related. The 'squatter' really seemed to have no plans for his site--if you go to http://juliaroberts.com (beware of the bad javascript), you can see that he tried to make a bulletin board out of it. In essence, he just occupied the space, and who knows what his eventual plans were. I can see someone getting upset over this. Read the details here.

Meanwhile, the case we have here is nothing like that at all. Its about a corporation protecting a trademark, and further more there seems to be no malicious intent at all from these people to infringe on that trademark. The name 'barbie' in the clan DOES refer to a Mattell toy as an icon applied to women gamers, but if the site was about bbqing, would Mattell still care?

The domain name was simply a bad choice. I think it sucks, but it'll probably have to go.

-S

http://students.washington.edu/steve0/
steve0@u.washington.edu

GREAT links, moderate that one up! Thank you!!!! Ignorance cured.

How many languages that do relatively the same thing do we need???

-S

http://students.washington.edu/steve0/
steve0@u.washington.edu