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You're missing the point. Distributed computing is not about only running on machines that aren't yours, but also efficiently utilizing the machines that are yours (or at least have easy access to).

Consider that a University of Wisconsin study showed that, on average, computers on desktops are idle at least 60% of the time. And that doesn't count the cycles burned lost between keystrokes --- I'm talking about extended periods of time. For example, almost all desktop machines are idle during nights. That's 50% already. Now add lunch time. Meetings, etc.

That's when systems like Condor come in. Researchers at Wisconsin got hundreds of years of CPU time on machines they already had without impacting others.

Coming back to your argument, the counter argument is that you may not even need to buy additional boxes --- just use the ones you already have more efficiently by utilizing distributed computing systems.

As far as "freeness" of processor cycles, let me tell you that the optimization researchers can soak up as much cpu as you can possibly throw at them. Also, if you look up Particle Physics Data Grid (PPDG) and GriPhyn, you'll find out that many distributed computing problems are I/O driven.

++Rajesh

Condor is a very good Grid system that is freely available for Linux (binaries only).

This is a little surprising that it got posted and all because it's not all that earth shatterning news, but I'll provides some additional information about grids in General.

There are a wide variety of systems like this that are either currently available or are being developed. Among them are Particle Physics Data Grid, NEESGrid and various European and Asian counterparts.

The basic premise is to allow access to various resources you don't have at your desktop. This is not to be confused to with putting all these computers together an forking a process a billion times and having it run it run all over the globe. It's more like saying I have a process that requires 128 processors and 4GB of ram, go find it an run it for me.

Most of the systems use Globus which is pretty much the defacto standard. There are other systems out there such as Legion and Condor which serve slightly different purposes.

I've also seen some issues about security raised, so I'll mention them quickly. Globus is built upon an API called GSS (Generic Security System), I believe it will soon (if not already) have an RFC published. This is a layer on top of various other security systems that may be local to the server running it. It can use Kerberos or PKI to do encryption across the network (don't flame me if it's wrong, I'm not security expert).

When I wish to start using the grid, I start up my proxy that takes care of all authentication for me. Then my proxy connects to the gatekeeper on the remote machine which authenticates me based on my private key and then authorizes me via a mapping (usually just a text file). The task is then executed by the gatekeeper via the mapping on the remote machine. Input and output can be redirected over a secure layer if you so desire.

My certificate is issued by an authority. In this case the Globus CA. The nice thing if that if you want to set up a grid of your own computers, you can get a cert from them too. Install Globus and it will tell you how.

Certificates also allow you to get access to data. This allows me as a user A to run program B at site C providing results to user D at site E for a period of time F.

It's all terribly neat and remarkably easy to install on your favorite Linux or Solaris box. It's also fairly easy to write programs to utilize the Grid thanks to the various CogKits for Python, Java and Perl.

If you read the "Bell Curve"

Reactionary stuff

An entire website, of course

And finally a sample of the peer review that was avoided. A small quote:

We conclude that The Bell Curve is driven by advocacy for Herrnstein and Murray's vision, not by serious empirical analysis. America may or may not be on the way toward a custodial state. Policy interventions may or may not be effective. We know no more after studying The Bell Curve than we did before.

Can one person have pulled of this crack, certainly . Did they work in a vacuum? Probably not, there is a cracking community and one would be a fool not to call the community knowledge in it. The idea of a corp. breaking a system that has had collectively hundreds of millions of dollars of R&D, and many many years invested into security for $5 million dollars (probably less) and 6 months is no less scary then a lone hacker, and to a security engineer probably more so. A lone cracker solves the problem almost randomly, and any particular cracker can not be relied upon to quickly crack a system. The idea that an org could fund this, and perhaps reliably crack the protection methods has far reaching consequences, and makes information warfare a realistic posibility.

Microsoft recently donated some winxp machines to a computer club I'm in. Naturally, we gave them names which evoked our feelings about Microsoft: war.upl.cs.wisc.edu, famine.upl.cs.wisc.edu, death.upl.cs.wisc.edu, and pestilence.upl.cs.wic.edu. : ) Incidentally, the unix and linux machines are named after Star Trek characters. Typical geek stuff.

Oh, and at my job, a research project called Condor, all the machines are named after birds or bird components. We have blackbird.cs.wisc.edu, firebird.cs.wisc.edu, perdita.cs.wisc.edu, robin.cs.wisc.edu, beak.cs.wisc.edu, vulture.cs.wisc.edu, and bunch of others.

Microsoft recently donated some winxp machines to a computer club I'm in. Naturally, we gave them names which evoked our feelings about Microsoft: war.upl.cs.wisc.edu, famine.upl.cs.wisc.edu, death.upl.cs.wisc.edu, and pestilence.upl.cs.wic.edu. : ) Incidentally, the unix and linux machines are named after Star Trek characters. Typical geek stuff.

Oh, and at my job, a research project called Condor, all the machines are named after birds or bird components. We have blackbird.cs.wisc.edu, firebird.cs.wisc.edu, perdita.cs.wisc.edu, robin.cs.wisc.edu, beak.cs.wisc.edu, vulture.cs.wisc.edu, and bunch of others.

All I can say is, check again. Diatomic oxygen (02 - a standard oxygen molecule) absorbs UV, but only up to 240nm wavelength. When it does this, it breaks down into free oxygen atoms, and frequently re-combines with another oxygen molecule to form ozone (O3).

Ozone absorbs UV radiation between 240 and 320 nm. Without the ozone in the upper atmosphere, this UV radiation would make it through to the surface of the earth.

For details on the chemistry of ozone, check here. More information can be found here, here, here, and many other places on the web.

Please, before popping off on a scientific issue, check the facts and not the politics.

No. Their half-lives are far too long. For an RTG, you need a radioactive isotope with a relatively short half-life, such as Pu238 or Sr90. See here.

Based on the press release, the slime is a modified polyacryamide. This page has a good primer on polymers and some of their chemical properties. It looks like this slime will be most useful in the desert, since rioters can wash it off with *lots* of water. Apparently, salt water woud works even better. I knew that there was some reason for taking chemistry in high school. Along with the second amendment, a widely educated electroate is the best defense of democracy.

I guess I should consider myself lucky. I attend the University of Wisconsin, where Unix/Linux servers outnumber windows servers more than 5 to 1. There is a similar statistic for lab computers. All CS students are obligated to learn Unix by the time they get to CS 352, with hundreds of Unix tutorial classes along the way. It doesn't stop there, most CS professors have written "handin" bash scripts to allow students to hand in assignments by ssh'ing in to 1 of the 50 available tux (Red Hat 7.2) servers or 1 of the over 100 available nova servers set aside just for CS students to use to do assignments. It's quite humorous to me to hear that the prognosis isn't very good, because on this campus of over 40,000 students, you can walk around all day and not see one start menu. If M$ was trying to buy our CS department, I think I can safely say they have long since given up, because the only progression this campus is making is from Sun to Red Hat. Life is good...

As other psoters have mentioned, Uranium does not have medical uses.

However, Plutonium-238 was (is?) used as a power source in some pacemakers. It's not the bomb isotope, so I guess this detector will be able to tell the difference.

You could view this post script file online here, or you could use the Windows, OS/2 or Linux viewers available here.

Rich Media, Poor Democracy: Communication Politics in Dubious Times, is an (as I said) excellent book by Robert W. McChesney, is a comprehensive story of how giant corporations are taking control of the mass media. It's not quite the same as having to be to get an ad-free slashdot, but it seems quite related to me. Here's a description:

"Rich Media, Poor Democracy addresses the corporate media explosion and the corresponding implosion of public life that characterizes our times. Challenging the assumption that a society drenched in commercial information "choices" is ipso facto a democratic one, McChesney argues that the major beneficiaries of the so-called Information Age are wealthy investors, advertisers, and a handful of enormous media, computer, and telecommunications corporations. This concentrated corporate control, McChesney maintains, is disastrous for any notion of participatory democracy."

(That was from bn.com.)

It lays bare, among other things, the myth of the "free" (NOT as in beer, or speech) market, and an analysis of the Internet and its potential direction (McChesney doesn't think it will set us free). And so on. It's damn good.

Let me put it this way: I attended a workshop with McChesney and John Nichols (editor at John Nichols (The Nation, The Capital Times) at RadFest 2001. Nothing at that conference got me more riled up than listening to their discussion about media megaconglomerates. Ohhhh...

Media, and media ownership, is rapidly becoming what Linux was to me two years ago. It affects more people more directly than free software does -- although I have not abandoned free software. Just wait... I've got somethin' up my sleeves for that. :-)

-- haaz.

If you are interested in MIPS you can get an assembler here. I used this assembler in my intro to computer architecture class.

Dont forget about spim,

Spim homepage

Spim is a MIPS assembly simulator for windows and linux. I am currently using it for a programming class at my University.

To let people know the costs of some of these journals, here are a couple of sites to look at.

First, a general overview of costs in the mid-90s (done in 2000, so just imagine how expensive they are now!) can be found here.

A more recent review of chemistry journals can be found here. It is amazing to think that some of these journals cost ~$4.50 a page (neuroscience journals are even more expensive!).

Simple sanity-checking should have pointed out to him that The Altair(tm) was invented before the Star Wars franchise ever got under steam. Just a bit of googling around would have found him the story he was looking for...

Not for a character from Star Wars, but a planet, from Forbidden Planet.

The planet, too, was named for the star, Alpha Aquilae. but is outside the scope of the movie, the book, and apparently the author's skull.

There's also a persistent rumor (through Google, that may be part of the souce of his confusion) that the computer was named after a character or a planet from a Star Trek episode, but no such episode apparently exists.

It's a strange day indeed, when Slashdot editors find themselves in better stead, for typos and fact-checking than the subjects of their articles, but these be strange days surely.

Condor is general-purpose, scalable, freely available (binaries-only), and runs on Linux.

I think this is it: http://www.mudlib.org/~rassilon/p2c/

we just had this happen in my high school chemistry class

I too had a recent revelation.

Given the local density of the universe, there should be around 100 star systems within 20 lightyears of the Earth. In fact, we've already identified 76 such star systems. For those that are interested this site lists the closest 26 stars (as opposed to star systems, which might be binary, trinary, etc.). There is also a more technical listing of the 100 closest known star systems (out to 24 lightyears).

Expanding away geometrically there would be about 1,700 star systems within 50 lightyears, and 13,000 within 100 lightyears. Fact of the matter is we don't even know which stars most of these are, since the majority of stars are relatively small and small stars rarely have their distance calculated.

If we ever do figure out how to get up close to light speed, then there is plenty of real estate to explore. Hell, if it turns out that life really is quite common, then maybe little green men actually can afford to come visit us.

here

1. Build it into the application. Numerical methods developers have been known to do this.
   Many people in the parallel discrete event simulation community do this, sometimes using
   compiler assisted tools.
   
2. Build it into a middleware layer --- this is the approach typically taken by many database management systems, in parallel discrete event simulation toolkits , and in distributed process migration toolkits such as Condor and BSP
   
3. Build it into the kernel --- this was done by keykos and the eros group. If the kernel has support for persistent objects and the application uses this support, process restart is well defined. I've seen limited forms of suspend and wakeup for mobile devices as well, but this requires an explicit suspend/restart rather than fast crash recovery like eros has.
   

A good place to start is the technical report from the UW's Condor project here

As the poster said, there are plenty of others:

• SGI IRIX and Cray UNICOS provide kernel-level checkpoint-restart.
• Condor provides user-level checkpoint restart and process migration by manipulating libraries at runtime.
• esky provides user-level checkpoint restart under Solaris and Linux via runtime library manipulation.
• crak provides kernel-level checkpoint restart for linux.
• cocheck provides user-level checkpoint-restart.
• libckpt provides user-level checkpoint-restart.

The condor project is still alive and well: http://www.cs.wisc.edu/condor/ and should do what this guy wants to accomplish (but not what he's asking).

UW-Madison (which has the largest fusion studies program in the nation) seems to be rather interested in H-3, so much so that the Fusion Technology Institute here has designed a device for mining H-3 from the moon. Interesting stuff, check out the website.

UW-Madison (which has the largest fusion studies program in the nation) seems to be rather interested in H-3, so much so that the Fusion Technology Institute here has designed a device for mining H-3 from the moon. Interesting stuff, check out the website.

MRI (magnetic resonance imaging) involves no moving parts. I think yon meant "Spiral CT"

Hmm... you're right. The "spiral" in Spiral MRI evidently refers to frequency/amplitude space rather than physical space.

Just use Mr. T's van

It's heluva fast

No...UltraSPARCs are the choice for enterprise applications that are I/O intensive. However our simulation's are CPU-bound are require very little I/O. PC's have a better price/performance ratio for pure CPU performance...much better! Plus we use Condor to run several simulations at the same time on Linux.

Um.. you are wrong, so I'll correct you. "Glow in the dark" stuff glows because a chemical reaction is happening

These guys actually brought light to a hault

Um.. you are wrong, so I'll correct you. Glow in the dark stuff glows because its electrons are easy to bump into higher orbitals (by absorbing photons), then slowly come back down (by emitting other photons).

These guys have a special supercooled substance that -- guess what -- absorbs photons into electron orbitals, then emits other photons! It's the same damn thing, except that in this case the photons coming out are the same color and have the same direction as the ones that went in.

Aren't there open-source apps that can read Word documents and PDF files (Ghostscript and StarOffice)?

And more to the point, why should we expect someone presenting an open-source alternative to a predominantly Windows-based audience to present it in non-Windows formats? Are we really that zealous, that we expect organizations to convert completely to open-source alternatives before they can even mention Linux on their website? And didn't we just cover this subject?

I grew up in the rural South, and I remember folk who considered it acceptable to use racial slurs when in a whites-only group, because it was safe to assume that most everyone would agree, and those that didn't would remain silent. Thankfully, times have changed—now I have to read Slashdot to find that kind of intolerance.

If we're going to act like a bunch of militant fundamentalists, I think I might just sit this year out. Please wake me when the zealots stop screaming in the hallway.

• X for the disabled (scroll down a little bit)
• University of Wisconin Trace Center
• Sun's Accessibility Program (including GNOME)

I found an article which says that this corn doesn't cross-breed anyways. IANAB, as usual. But why is this a risk?

Sounds truly interesting. I suppose you don't have any links yet?

Sorry, no. The only thing that's close to release is a related framework component, STEnterprise (heh, let's see if we get sued for that name :-), which is intended to be a database independent object persistence layer (needed by some of the specialized managers in the MOM) intended to address the fact that Apple has mishandled EOF. That's due out at the end of the month, but it's not a major part of the STMOM framework, which is the core of Mary and MaryTool (the command line version).

Since there is growing interest in an updated user experience, I can provide a few links that I found inspirational in my work on Mary as a MOM.

• The Anti-Mac Interface got it right in 1996, but we didn't have the vast datastore on the desktop to make it worth it, or the processing power to make it happen.
• Liquid File System, insightful enough for me to say "screw it" to my own white paper and just implement the damn thing. :-)
• Placeless Documents, an excellent paper, as you might expect from Xerox PARC.
• SQLite, useful if you need to release software that would benefit from a database on a system that might not have one.
• Shore, which interestingly can have the object store accessible using directory navigation, addressing some migration issues.

filterproxy let's you exactly do that. check it out. it's written in perl, and configurable through a web interface. it has many nice other features: gzip content-transferencoding being one. definitly worth to check out.
http://freshmeat.net/projects/filterproxy/
http://draal.physics.wisc.edu/FilterProxy/

Sleepcat Software's open source Berkeley DB has "been profitable since inception" in 1996

Using multiple licensing models L. Peter Deutsch is able to provide Ghostscript under the GPL and make enough money to retire.

Cygnus Support (now part of Red Hat), was founded in 1989 and was "profitable, increasingly profitable, every single year" before the Red Hat buyout.

It's very unconvential, O'Reilly must be happy enough with sales of books to pay Larry Wall to keep developing Perl.

Open Source works. Maybe not as well as VA Linu... erm... Systems wants it to, but it does.

The race began Oct. 7 at Los Gigantes Harbor in Tenerife, Spain, and ends in Port St. Charles, Barbados.

Is there a good reason they're rowing against the gulf stream and the prevailing winds?

As if rowing across the atlantic isn't hard enough already

• X for the disabled (scroll down a little bit)
  
• University of Wisconin Trace Center
  
• Sun's Accessibility Program (including GNOME)
  

...to the GhostScript open-source PDF reader, right beside the link for Adobe Acrobat. Sadly, though, the link is broken, thanks to an extra space at the end.

Atention to detale is impotent!

Hmm... this is gonna give me brain strain... :)

Borrowing from the PDF doc found at: this location on the public docs site, here's what I could grep out:

(from page 2, par 2): "... We show that this limit is accessible by operating a kilometer-scale neutrino observatory over several years."

(from page 2, par 3): "... Although the flux from a single source may still be small, this conclusion is credible because a neutrino telescope will be operated for a decade."

Basically, I think the intrinsic accuracy in the system lies largely in the fact that it will be operated for a long duration. This temporal note affects multiple portions of the problem, acting as an averaging and error-correction mechanism (at least as far as I can tell).

So, given enough data (ala' Seti@Home), it should be possible to pay attention to the general outstanding trends produced from analysis, even given somewhat of a shift or "settling/sliding" in ice conditions.

Please forgive me awful German; I tried to grok the site you pointed me at, but it just made my brain hurt :(. I need to bone up on more than just my native tongue (comes in handy for playing chess online too).

...I found this line in the original proposal: "These constraints lead to a strawman design consisting of 81 strings 125 m apart, arranged on a square 9×9 grid. Each string holds 60 optical modules separated by 16 m."

There are good graphics showing how they'll be arranged, and explanation of how this design will facilitate ~1 resolution in muon trail reconstructions. Impressive!

I also found elsewhere that faint Cherenkov radiation can travel more than 24 meters through deep Antarctic ice before being completely attenuated. So that question is answered.

• Tech Talk About C++ and C
  
• PGI Workstation User's Guide
  
• Fortran and C/C++ Mixed Programming
  

Ozone is actually a respiratory irritant. Here is a small blurb on it. In short, Ozone at the surface of the Earth is bad, and would probably react with other compounds in the atmosphere before it had a chance to rise up to where it would not be a health risk and would absorb UV light.

Comment 1 RE:Linked directly to Postscript?

Try using ghostscript/GSView which will display the postscript file directly. (A quick search on Google gave the following link which should be useful
GhostScript

Comment 2: I don't think this is ever really likely to be part of 'consumer' system. FPGA's are great for
1) prototyping circuits that will later be implemented as an ASIC where the cost of "respinning" a chip is extremely high or
2) Situations where the system is only produced in very small numbers.

The main problems with FPGAs are that they are
1)Expensive!.
2) Relatively small in terms of the gates they can implement and
3) The clock speed that can be achieved is probably about an order of magnitude lower than an equivalent ASIC.

For many situations a multi-CPU system may be a much better option, and I certainly think that they'd be impractical for a mass produced system.

Simon

Don't forget white phosphorus. It spontaneously combusts at room temperature, like a Spinal Tap drummer.

These pages are currently /.'ed, but they sell 5 CD-ROMs of these videos for $60 each to individuals in the USA, more for multi-user and non-USA.

check this link. It's the first link on the page (which is unreachable by now).

Ferrofluids are colloidal suspensions of nanoscale magnetic particles in a carrier fluid; the particles form magnetic domains separated by coats of dispersant only a molecule thick. These magnetic fluids have been used in many ways--to form airtight seals around rapidly moving parts, to move drugs in the bloodstream and rocket propellants in spacecraft, even to cool and dampen powerful audio speakers. Now steerable ferrofluids may give rise to new tools for subsurface environmental engineering and laboratory safety.

At Berkeley, they use magnetic fluids to control movement of underground fluids without any contact. Interesting stuff. For an introduction to ferrofluids, see University of Wisconsin's excellent article.