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• Monte Davidoff - co-author (along with Gates and Allen) of Microsoft/Altair BASIC
  
  
• Richard Stallman - Pioneer of open software movement/GNU
  
  
• Niklaus Wirth - PARC researcher responsible for Algol, Pascal, Modula-2, Laser Printers, and more
  
  
• Marvin Minsky - Built the first neural net AI in 1951
  
  
• Seymour Papert - Developer of LOGO and another AI pioneer
  
  
• Tommy Flowers - Built one of the earliest electronic computers, with the practical application of codebreaking during WWII
  
  
• Donald Knuth - Regarded by many as the "Father of Computer Science".
  
  
• Edsger Wybe Dijkstra - The guy leading the way to abolish the GOTO statement is surely a hall-of-famer!
  
  
• Konrad Zuse - Another early computer pioneer that due to politics and circumstances beyond his control was never able to be fully-recognized.
  
  
• Jeff Raskin - Creator of the Macintosh and pioneer in computer-human interfaces.
  

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

The University of Texas College of Liberal Arts ITS has been pursuing projects like this for a few years, with their French, Spanish and Texas Politics textbooks.

Just look at the matrix multiplication case. Look at the graph and see that 1000x1000 takes 30 seconds on CPU and 7 seconds on GPU. Let's translate it to Millions of operations per second: CPU -> 33 Mop/s, GPU -> 142 Mop/s Matrix multiplication has cubic complexity so for CPU: 1000 * 1000 * 1000 / 7 seconds / 1000000 = 33 Mop/s

Now think a while: 33 million operations on 1.5 GHz Pentium 4 with SSE (I assume there is no SSE2). Pentium 4 has fuse multiply-add unit which makes it do two ops per clock. So we get 3 billion ops per second peak performance! What they claim is that the CPU is 100 times slower for matrix multiply. That is unlikely. You can get 2/3 of peak on Pentium 4. Just look at ATLAS or FLAME projects. If you use one of these projects you can multiply 1000 matrix in half a second: 14 times faster than the quoted GPU.

Another thing is the floating point arithmetic. GPU uses 32-bit numbers (at most). This is too small for most scientific codes. CPU can do 64-bits. Also, if you use 32-bits on CPU it will be 4 times as fast as 64-bit (SSE extension). So in 32-bit mode, Pentium 4 is 28 times faster than the quoted GPU.

Finally, the length of the program. The reason matrix multiply was chosen is becuase it can be encoded in very short code - three simple loops. This fits well with 128-instruction vertex code length. You don't have to keep reloading the code. For more challenging codes it will exceed allowed vertex code length. The three loop matrix multiply implementation stresses memory bandwidth. And CPU has MB/s and GPU has GB/s. No wonder GPU wins. But I can guess that without making any tests.

Hyperthreading (or simultaneous multithreading - SMT) creates the ability to run 2 virtual threads on a single chip. This can be as simple as running an 'integer' and a 'floating point' thread, as the SIMD/FPU are really still separate units anyways. In a more complicated form, it means multiple threads are split across different pipes/units/stages - making more use of the processor if you like.

Dual Cores are 2 actualy processor 'cores' on the one chip. That's 2 LSU's, 2 FPU', 2 IFU's, etc plus as much L2 cache you can shove on to feed 'em.

It is like having 2 real proc's....it's just more efficient to make dual core chips than 2 separate ones. Ofcourse you still need an OS that is good at handling multiple processors - which windows isn't really (compared to OSX for example). Speaking of Apple - IBM have been making dual core chips for some time now. The POWER4 was dual core, and the POWER5 is dual core and multithreading! Lots of Apple rumor sites are saying that the next Mac chip (G6?) will be IBM's 980 - supposedly based on the POWER5, ie dual cores etc etc.

Here's a link to an IBM presentation with a bit of info on SMT & dual cores (pdf, sorry).

Yes, but ever since the demise of Bongo (the old www.utexas.edu VAX) the only non-departmental computing system on main campus of note is the IBM SP2 node running the administrative database stuff (grades, security, finances, etc... can't remember the name off the top of my head). That pales in comparison to the machines at J.J. Pickle Research Campus at the other end of Austin. Plus Pickle is where we hide the reactor.

Yes, but ever since the demise of Bongo (the old www.utexas.edu VAX) the only non-departmental computing system on main campus of note is the IBM SP2 node running the administrative database stuff (grades, security, finances, etc... can't remember the name off the top of my head). That pales in comparison to the machines at J.J. Pickle Research Campus at the other end of Austin. Plus Pickle is where we hide the reactor.

I go to utexas.edu. I can vouch for the administrative craziness that all too often plagues this school. :)

This is the same place where the suits did everything they could to keep the FOIA and other legal mechanisms from revealing information about the post-9/11 surveillance system. UT even went after our state attorney general over this. A friend of mine said it best: "Never sue someone when they have a law school." ;)

The whole reference to UTWatch in the article creeped me out. UTWatch is a student-run organization which follows up on what the regents and other suits do. Like Ralph Nader in the 70s, its a mere watchdog organization checking if proposed policies will adversely affect the student body at large. Recently they have been very vocal speaking out concerning tuitition deregulation and the involvement of UT managing the Los Alamos laboratories. Not simply fact checkers, UTWatch does get involved when it smells something fishy.

I applaud what Mark Miller did. There is all sorts of cool things under the ground here at UT. Under ENS and RLM you can find a retired tokamak! More than just he are interested in whats buried. Simply put, what UT did (assuming it did something to spur this) simply lacked honor. ;)

For a better analysis of optimization in this specific part of the sort space, I recommend Jon Bentley's classic "Engineering a sort function".

This paper discuss how to implement an optimal sort, after having done real-life measurements. Conclusions include dropping to an O(N^2) sort algorithm when qsort partitions become small enough - insertion sort was choosen. (The selected cut off was secven elements at that point; it may be that it would be sensible to choose a higher cutoff for the generic case now, as the cache locality might help. However, I won't bet on this either way without doing measurements.)

The qsort implemented there is the one still used in at least FreeBSD. I don't know the status for other OSen.

As for big O notation: The discussion in the previous post is so imprecise as to be misleading. It use "cost" and "complexity" where it discuss asymptotic complexity; these are distinctly different, and it is necessary to be quite clear on the distinctions to do correct analyses.

Big-O notation measure asymptotic complexity over an arbitrarily selected set of basic operations assumed to have unit cost. It discard all constants to make the analysis easy to do and easy to work with. This is a useful tool, but it only measure asymptotic complexity, and it only does it based on arbitrary basic operations.

In practice, a mere factor 1000 speed difference (one second to twenty minutes) might be quite noticable. This will be REMOVED from the big-O analysis, which can make it point in a quite different direction from the truth.

In the parent post, sorting 1000 elements is assigned a unit cost, claiming that the time will be similar for a bubble sort and a quick sort, and "low enough not to matter". Further, the conclusion is "never use bubble sort". Assuming a naive implementation of both bubble sort and quick sort, and a set of arrays that is already sorted, the quicksort will be O(N^2) and the bubble sort will be O(N) in the number of items in each bin. This is a quite noticable difference in asymptotic complexity.

A naive programmer is in my opinion the only relevant assumption if we're to give absolute advice on simple sort functions. A non-naive programmer will know how to do complexity evaluation, will know the tradeoffs on startup of the various algorithms, and will only be implementing a sort him- or herself because actual speed measurements or specific knowledge of the sort behaviour show that the system supplied sort is not fast enough for the case in question, and that a custom sort can do better. (S)he will also evaluate whether the data to sort is likely to be almost sorted or highly random, and thus which kind of algorithm is likely to go faster. (And insertion sort/bubble sort is actually faster also for large data sets if they're almost sorted beforehand.)

Eivind, who if he had to give general advice would give "evaluate qsort, mergesort, heapsort, insertion sort, and using a data structure that keeps order before choosing bubble sort."

The only feasible retrieval scenario was determined to be aerial capture, shown in Figure 11. This method was used in the CIA's Corona program, the first successful spy satellite system. The photographs taken by the Corona satellites were deployed from the satellite in film canisters to be retrieved by aerial capture. Aerial capture was used so that no one would have the opportunity to access the spy photographs.

No, the quote is correct. See the original manuscript:

http://www.cs.utexas.edu/users/EWD/ewd04xx/EWD498. PDF

back on topic...
A great resource on this topic is all the work done previously, like:

• The 50-page journal available from the Ford Library: link
• this list of sightings

The last czarina of Russia was purported to have a cross pendant made from a timber from their expedition to see Noah's Ark over a century ago.

Researchers are focusing on the wrong Ark. They should be after the Ark of the Covenant. I can just see the ACLU screaming about that being on display at the Smithsonian, what with their self-fashioned "separation" nonsense (go read the Federalist Papers). If the Jews had that Ark handy, then they could really rule with FUD.

Wow... I didn't know a 1Gig mail tidbit could make a self-proclaimed geek community lash out with such blatant hatred.

But since it's out there...

I'll make it short,

200 years ago, Jews are scattered throughout Europe, banned from all guilds, Jews are forced to practice trade and commerce.

100 years ago, Jews are thriving, strangely enough relentless persecution follows, the sought after euphoric notion of coexistence diminishes. MY ancestors seek sanctuary.

50 years ago, Jews have been slaughtered by the millions, NO MORE!

MY forefathers built me a HOME, Israel.
Putting aside the biblical records of Jewish settlements; legitimately occupying a 470 Kilometers strip of land (Size) is crucial to our survival and sovereignty.
I am 23 years old, I've volunteered 4 years of my life to DEFEND my only HOME, just like my father, and my grandfather before him, have we not done so, Israel would have been bereft of its existence. (Israeli wars)
I spent my first 2 years in the army learning how to dismantle and operate an assault rifle in a heartbeat, walk 50 miles packing 100 pounds of gear, and adhere to the strictest rules of ethical conduct. I spent the rest of my service operating indigenous strategic positioning and command systems (Westwood beware).

I'd much rather have spent my best years partying in college...

But I was left with no choice; we've learned our lesson, Jews must fend for themselves, unwillingly we have to relay a strong message to the world:

You don't FUCK with Israel.

Our survival depends on it. (Green=Foe)

using quantum mirrors, you could possibly split the light stream into two separate streams without altering the quantum state, and get perfect copy of the data real time

On an interesting note, all of my friends that graduated from EE are making ~$50K. (funny thing is half of them are doing coding jobs and I've seen the quality of their code... it ain't a pretty picture :-X )

It seems like to me IMHO that most companies are getting MIS and Computer Science majors confused...

The argument here isn't that the schools on the list only made it because they're small thus making reliable service easier to provide; just speculation about how much of a weighted factor this was.

One must also consider that some schools--such as UT and Harvard--are more likely to host a higher percentage of students and faculty who are interested in wireless access. So maybe Intel ranked Harvard lower because the wireless access there fails to meet student demand? (Building age and construction materials also are callenges, as others have pointed-out.)

UT/Austin is the one of the only schools on the list who's presence didn't surprise me. So the question here is, given the comparitively large student population, why wasn't UT/Austin #1 if the signal saturation is as complete as you claim (assuming that the signal was equally reliable in all buildings, which is a big assumption)?

For one thing, if Intel's methodology was objective, then maybe access in key UT buildings isn't so hot.

Further, Bloomington's population is only about 60,000, so the student population is probably considerably smaller than UT's. University size has to be gauged both in terms of student population and the cumulative campus area. So, while serving a smaller population, Bloomington's campus is very sparse and appears to cover more area than UT's much more condensed main campus.

Jeff Sylvester, in a discussion on the Unofficial Empeg BBS, wrote a program to graph this very phenomenon. With this program, you can clearly see how a truly random distribution will produce exactly these kinds of perceived "patterns".

On universities, 99% of computers run with nearly zero CPU load for most of the time. Now imagine, we install a "cluster server" on all networked computers.

Some universities, such as my own University of Texas at Austin, are doing just that.

Your comments remind me of an old QA maxim: "We can only prove the existance of bugs - not the absense of them."

You invoke the magic buzzwords of "modular design" as if it were a new thing. It isn't. That concept is older - in practice, even - than the median user on /.. Edsger W. Dijkstra was one of the earliest proponents of such coding practices - you can find archives of his papers HERE and see for yourself.

Magic buzzwords can't prevent defects from occurring. QA can't find them all, no matter the budget or amount of time they spend on it. You can only minimize the effects of bugs and put procedures in place to deal with them, programatically and non-programatically.

"Our software contains no known undetected bugs."

True. Any argument is only as good as it's assumptions.

You may find the following project interesting:
It [acl2] is a common lisp programming language and a system for proving properties about code. It has been used to prove correctness properties about microprocessors[microcode], compilers, and application code. Notably, I believe it is currently being used to prove certain properties about the Java Sandbox.

When the FDIV bug was reported, AMD hired it's creators to mechanically verify correctness of it's floating point microcode on a model of the K5 developed on the system. Details

In fact, they were unable to verify it's correctness, as it wasn't correct. Fortunately, the code was able to be changed, prior to chip fabrication, saving AMD a lot of money and a lot of embarassment.

True. Any argument is only as good as it's assumptions.

You may find the following project interesting:
It [acl2] is a common lisp programming language and a system for proving properties about code. It has been used to prove correctness properties about microprocessors[microcode], compilers, and application code. Notably, I believe it is currently being used to prove certain properties about the Java Sandbox.

When the FDIV bug was reported, AMD hired it's creators to mechanically verify correctness of it's floating point microcode on a model of the K5 developed on the system. Details

In fact, they were unable to verify it's correctness, as it wasn't correct. Fortunately, the code was able to be changed, prior to chip fabrication, saving AMD a lot of money and a lot of embarassment.

Xiaolong Wang

"Chow Long Wang" ... brilliant.

There used to be a sysadmin who worked where I now work who used to big on everything2.com. One of his greatest nodes was this one. It discussed in absurdly great length the theoretical "bandwidth" of "a station wagon full of quarter-inch tapes".

It made me laugh picturing this guy writing this. Because this is the guy who would suspend production servers from ropes dangling from ceiling AC ducts. ;)

From here:

Phobos's orbit is slowly decaying, spiraling in towards Mars, so that Martian tidal forces may overcome the satellite's own gravity and break Phobos up into a ring like Saturn's, perhaps within 50 million years. Deimos may, like our Moon, be slowly spiraling outward.

I'd say your news of Phobos' imminent demise is greatly exaggerated. Before that happens we'll have used it as a counterweight for a Martian space elevator anyway.

Your use of parentheses there is amusing and sad. You do know that those parentheses denote serialized lists, right? You've just made a list of a list of a list of a ...

Sheesh, learn a little about the language before you go making fun of it.

• Played Jak & Daxter or any of its sequels
• Played Abuse
• Booked a reservation on Orbitz
• Visited the campaign web sites of Bill Clinton in '96 or Howard Dean in '04
• Used the Mirai facial-animation software or watched Gollum in Two Towers / RoTK
• Used an AMD processor, parts of whose logic is validated via the ACL2 theorem-prover software
• Used GNU/XEmacs
• Used AutoCAD
• Used the lisppaste pastebot on a bunch of channels on Freenode

Not all the world is a desktop application with a GUI. Lisp and the other languages aren't going away in this space anytime soon. It's just too cumbersome to do many of these things in C++, and too slow to do them in Java (Common Lisp is usually native compiled).

This is also why the government keeps up the Interstate highways. In theory, in the state of war on the US mainland, the Army could easily control any stretch of Interstate highway so that vital convoys could have a fast and trafic-free mostly-direct path from one metro area to another.

In theory nothing. This is exactly why the U.S. interstate highway system is so well developed. The intent was speficially to allow military vehicles quick access to any part of the country. Interstate highways were also designed such that the government (military, police, or whoever) could quickly take complete control of any given section simply by closing the on-ramps. Many sections were also built to be easily converted into ad-hoc runways for military aircraft.

You might also hear the highway system referred to as the National Defense Highways, but most likely only in your history books. Dwight D. Eisenhower lobbied and eventually convinced congress to pass the the Federal-Aid Highway Act of 1956, which would provide for 41,000 miles of road (total) by 1975.

This has been another Slashdot history lesson. Thank you.

Its scope is pretty limited, but JParanoia works pretty well for Paranoia games. You could probably shoehorn other games into it, but that might be ugly. And if youre lucky, you might even get to beta test some new Paranoia XP rules.

And that the only good nigger (aside from a dead one) is one that comes with a manual?

Why don't we all meet up in Texas for a nice swim in Dead Nigger Creek?

Doin' my part to help the GNAA!

Disclaimer:Not officially associated with the GNAA.

Werd to ya mutha

There's a similar project at the University of Texas at Austin. It aims to image Mayan pyramids in Belize.

They have a fairly sparse website, but there's a quite good PDF of a slides from a talk that Roy Schwitters (former director of the Superconducting Supercollider) gave.

There's a similar project at the University of Texas at Austin. It aims to image Mayan pyramids in Belize.

They have a fairly sparse website, but there's a quite good PDF of a slides from a talk that Roy Schwitters (former director of the Superconducting Supercollider) gave.

Where's our favourite term, as in "Damn Slashdot trolls! I got goatse d again!" or "space imitates goatse "?

Like this?

Many of the countries with the strictest gun control have the highest rates of violent crime.
Australia and England, which have virtually banned gun ownership, have the highest rates of
robbery, sexual assault, and assault with force of the top 17 industrialized countries.

In America, a gun crime is recorded as a gun crime. In Britain, a crime is only recorded when there
is a final disposition (a conviction). All unsolved gun crimes in Britain are not reported as gun crimes, grossly undercounting the amount of gun crime there. To make matters worse, British law enforcement has been exposed for falsifying criminal reports to create falsely lower crime figures, in part to preserve tourism.

If you're looking for more free online maths / physics texts, there are a great many avaliable.

Some CS people might be interested in the book on Information theory by Dave Mackay (author of Dasher). Unlike most people, he seems to have taken a truly "Open-Source" approach to book publishing.

No, you will have one more reason to understand them: the University of Texas has been giving elvish courses for years!.

And on the first day, the teacher said, "Mankoi lle irma sint, y'all?" And so y'all know, he ain't lyin'! =)

LIN 312 is a linguistics class on the languages of middle earth.

It's a real class for which you get real credit.

course description

Yes, schools and kids are objectively much safer than they used to be. This does not make for exciting news coverage, however, so this fact is rarely mentioned.

Joking aside, I can see these being heartily adopted by the hotel industry. Now they can offer you PPV pornos while you're on the toilet!

You may already know, but there's historical precedent for the concept. When I was 14, my folks and I passed through Wizard Wells, Texas, a declining community once known for its mineral water baths. There was still a small hotel/bathhouse there at the time (mid '80s) -- a very cool place, even to a tired, bored teenager.

But within the wooden bathroom stalls was the sort of surprise every tired, bored teenage boy dreams of -- each stall had a magazine rack filled with Playboy! w00t! (or the '80s equivalent thereof) Alas, it was time to hit the road.

Never have manged to go back that way... hope the place is still in business, Playboy or no.

Not me. It would be interesting to have a rule of thumb for the real economic cost of debugging this way.

We all (except Dijstra, perhaps) take trade-offs, for a reason. Perhaps that reason is only ignorance, but then we wouldn't get anything done.

The U.T. Police Department Web site has an interesting article about skimmers in use in the Austin area. Check out where they put the camera!

Check out this advisory put out by the Univ of Texas, Austin.

Saw this recently on memepool.com:

http://www.utexas.edu/admin/utpd/atm.html

OK, I should have included this the first time, but I only just had time to go find it. It's Edsger Dijkstra's hilarious satire "User-Friendly Mathematics" (links to PDF).

OK, I should have included this the first time, but I only just had time to go find it. It's Edsger Dijkstra's hilarious satire "User-Friendly Mathematics" (links to PDF).