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In these discussions I never see mention of software produced in academia. Guys, research software was open source decades before the term was first invented. NSF or DOE give us money to do research that involves producing software, and when the software is finished it typically goes on a web site. Ftp archive before the web was invented. If you use it, kindly acknowledge us.

Unfortunately some research software is completely forgettable, but there is plenty that is high quality. Just a few names: Lapack http://www.netlib.org/lapack/ does linear algebra software, has been around forever, and is in fact part of the Intel and IBM scientific libraries. Atlas http://www.netlib.org/atlas/ gives highly optimized kernels. We suspect that vendors take this as a code base for their own optimizations. Petsc http://www-unix.mcs.anl.gov/petsc/petsc-2/ is orders of magnitude better than anything available commercially, is now probably 10 years old, still developed and supported, and used all over by engineers and scientists.

Just thought I'd mention that model. No "kindness of big corporations" needed.

Victor.

Here's a FAQ: http://www-unix.mcs.anl.gov/otc/Guide/faq/linear-p rogramming-faq.html

What is most interesting about LP is not that it is just a method of finding the solution to a problem, but that it extends in range over many diverse fields from (obviously) computer programming to fields such as economics and even business planning.

Here's a FAQ: http://www-unix.mcs.anl.gov/otc/Guide/faq/linear-p rogramming-faq.html

What is most interesting about LP is not that it is just a method of finding the solution to a problem, but that it extends in range over many diverse fields from (obviously) computer programming to fields such as economics and even business planning.

The environmental movement has done a good job at requiring so many frivolous regulations that nuclear power in the US cannot be financially feasible, leading to increased pollution and disease due to other production methods.

However, with mismangement at the level we see at reactors like the Davis Besse reactor, we're lucky that these plants are offline most of the time.

If we really want to do nuclear power right, instead of designing each plan from scratch we should use the (US) design that the French use for all one of their plants. That way, the properties of the reactors would be well understood, and experience gained at one site would be directly transferrable to other sites.

Of course, with our current administration, if we use the design the French are fond of, we'll probably have to call it a "Freedom Reactor."

It might be better to use a more modern design that does not produce long-lasting nuclear waste, and can't melt down, but whatever we do, we should standardize on one reactor design. That would lower the costs of design, construction and operation without sacrificing safety.

Also, what idiot decided these things should be run by for-profit corporations? Has anyone else noticed that the safety of commercially run plants gets worse, not better, over time? (Do we really want Dogbert and the pointy-haired boss having final say over nuclear reactor operations?!?)

Of course, once somebody tosses one into an incinerator then the tritium will be directly released into the environment as radioactive H20, which is highly dangerous and doesn't need to penetrate your skin. Any nuclear battery with enough power to power a laptop (~20W) will contain a significant amount of total radioactivity, which would be a major concern if the battery were incinerated or corroded in a landfill. Therefore, you will never see these on the consumer market. Please try and be a little less ignorant. Really. You ever touched a doornob and seen blue sparks? That just did several times more damage than tritium decay could do to you. The energy leve is too low. http://www.ead.anl.gov/pub/doc/tritium.pdf Moreover, tritium has major WMD issues. All modern nuclear weapons use tritium to boost the fission core; it allows bombs to much more efficiently use their fissile fuel and provides a much more consistent yield. Currently, the world supply of tritium is tiny, and much of it is carefully hoarded by nuclear-capable states to keep the tritum boosters in their warheads replenished as they naturally decay. The powers that be will want to keep this key weapons material hard to obtain; this is another reason that governments are never going to allow significant amounts of tritium to be handled by the general public. Think of the children!!!! Seriously... Tritium is used for fusion, not fission bombs. It has a halflife of 12 years and must be kept "fresh" if you want a really big boom. In all honesty though, it is one of the most common radioactive materials you can come by. All governments really care about are the "sanity" of anybody that has amassed the equipment used to either massively concentrate natural sources of tritium, or those with reactors that make it. I ordered some of it off the net 6 months ago. Very common I promise. Tritium alone is almost worthelss. I imagine you could light it and burn somebody or something, but that is lame.

You'd be much better off reading about MPICH if you're into clustering. MPP is a lot more complicated than just networking a bunch of machines in a cluster configuration.

They don't have Beagle II on their site anywhere.

They do. 20:15 | 2003 Jun 02 17:45:00 | Mars Express. This was rated as a success although Beagle 2 failed, just like several other missions that sent data or images back even if they sent less than planned due to a malfunction in one of the instruments or probes.

For those of you keeping score in the grand game... http://www.bio.aps.anl.gov/~dgore/fun/PSL/index.ht ml

Subs generally utilize light water reactors instead of the more difficult to maintain liquid metal reactors.. Here is a page that gives a quick description of early Liquid Cooled reactors.

More links:

http://www.nuc.berkeley.edu/~gav/almr/01.intro.htm l
http://www.nuc.berkeley.edu/thyd/ne161/shir/projec t5.html
http://www.nucleartourist.com/type/metal.htm

However, it is possible for diamonds to burn.

http://www.newton.dep.anl.gov/askasci/chem00/chem0 0202.htm

I'm sorry if my original post sounded arrogant or accusatory. I'm honestly interested in knowing more about this technology. I'm happy to be corrected when I'm wrong, but it really helps to have sources to check.

With regard to flux, as far as I can tell, no one has reported a Fusor-style setup with a flux higher than 1E8 neutrons/second or perhaps 1E10 neutrons/second (example, example). Assuming an operating distance of 1 m, that's less than 1E5 n/(cm^2 s).

By comparison, modern reactor setups achieve 2E15 n/(cm^2 s) flux, and spallation sources can achieve 1E17 n/(cm^2 s) (see Fig 1 here). This is why I characterized a Fusor as "low flux." The flux of a Fusor is useful for some things, but for most applications of neutron beamlines, it is too weak. (Of course, more than flux matters: energy distribution also matters.)

From what I know, Fusors are great for studying some aspects of fusion reactions and maybe conducting experiments on neutron properties. I've also heard of using it for neutron interrogation (example), where you irradiate a sample and see what happens (for instance for characterizing nuclear samples, material identification, bomb detection). So, yes, it is a neutron source. However, it is not competitive with high-flux sources, and is (I think!) too weak for neutron scattering, diffraction, and imaging experiments. This is why I claimed that a fusor was not a general-purpose neutron source.

This is also why no Fusor sources are listed on any "worldwide neutron source" lists, as far as I can tell:
http://neutron.nrc-cnrc.gc.ca/links.html
http://www.ncnr.nist.gov/nsources.html
http://www.neutron.anl.gov/facilities.html
http://neutron.neutron-eu.net/n_users/n_where_the_ facilities/n_worldwide
http://www.sciner.com/Neutron/neutron_facilities_w orldwide.htm

With regard to the universities you mentioned, it looks like the PULSTAR at North Carolina State is a reactor. The TRIGA at University of Illinois at Urbana-Champaign is also a reactor. If those were not what you were referring to, then I apologize.

To recap: I relent and agree that a Fusor is indeed a viable neutron source. However, I would like to point out that its flux is much lower than other sources, making it unsuitable for many types of neutron beamline experiments. If I'm wrong about any of this, please correct me.

Two other systems are Otter a resolution-based theorem prover and the Boyer-Moore Theorem Prover - the classic Lisp-based inductive reasoning tool. Honestly, I find the inference-based reasoning of Otter to be a lot more straighforward and intuitive.

That is the dumbest thing I have read all week. First, the U.S. is not that far ahead of other nations as far as technology. The reason we are able to do really cool things - like maintain a space program - is because we have an economy (albeit an economy in decline) that can support such programs. The same goes for the military.

Second, the job of a professor depends on the University and their particular relationship with that University. Some professors spend most of their time researching, others teaching. Quite a bit of research is performed by PhD holders who are not professors. Those are the people about to get slammed. Much of our important research is performed at places like Argonne

Or for a graphical interface, try the ldapbrowser. http://www-unix.mcs.anl.gov/~gawor/ldap/

Microwave radiation couples to the dipole moment of water molecules, which makes them vibrate harder, causing a local rise in temperature, much like in a microwave oven. See this wikipedia article

Cells are very sensitive to heat: see this interesting article (in response to a question from a 13 year old, mind you)

"yes, DNA is distroyed if a living thing is heated: the cells of the organism are degraded by the heat, and that liberates enzymes, called DNAses, that eat away the DNA. So the cell destroys its own DNA when it is dying."

Or the increase of heat could directly change the DNA. DNA first melts and afterwards at higher local temperature bonds may break.

I have no idea which of these mechanisms may be stronger, but it is not too surprising to see degradation of DNA under the influence of RF radiation, even though direct breaking of bonds is energetically unlikely, as the parent rightfully points out.

Microwave radiation couples to the dipole moment of water molecules, which makes them vibrate harder, causing a local rise in temperature, much like in a microwave oven. See this wikipedia article

Cells are very sensitive to heat: see this interesting article (in response to a question from a 13 year old, mind you)

"yes, DNA is distroyed if a living thing is heated: the cells of the organism are degraded by the heat, and that liberates enzymes, called DNAses, that eat away the DNA. So the cell destroys its own DNA when it is dying."

Or the increase of heat could directly change the DNA. DNA first melts and afterwards at higher local temperature bonds may break.

I have no idea which of these mechanisms may be stronger, but it is not too surprising to see degradation of DNA under the influence of RF radiation, even though direct breaking of bonds is energetically unlikely, as the parent rightfully points out.

If only SuSE 9.2 came in a nifty boot Live CD version that booted directly into your choice of KDE or Gnome ...

Oh wait - it does, and I'm on it right now.
Get yours here :
FTP site with SuSE 9.2 Live CD/DVD iso files

For the record there are two issues :
1. Changes are not persisted to the hard drive (in fact it doesn't even touch the hard drive) so your favorites, any documents you create in OO, etc are lost if you reboot (but you can save them to a USB thumbdrive if you pop it in after the GUI is running, works nice)
2. It defaults to like 85Hz for display which freaks out LCD's. There is a fix out there, involved hitting ALT F2 to get to the command line, entering runlevel 3, using sax2 to reconfigure the display manually, going back to runlevel 5 (which I did to run on my machine at home, and on a laptop.)

It takes a while to get used to being in the safe environment, I still find myself not clicking on random URLs due to ingrained fear of spyware, drive by installs of crap, etc...

Coal contains radioactive material such as uranium.
http://www.newton.dep.anl.gov/askasci/gen99/gen994 02.HTM

Nuclear Waste can be recylced and refined. Among other ways, we can use a breeder reactor to re-enrich the spent fuel and reuse it in power plants. This would greatly decrease the amount of waste left over and the leftover would be much less radioactive. For some reason, no one seems to talk about this. Partly the reason we haven't done this is that Carter put a ban on them in the US. Overturn the ban, get much safer nuclear power.

Now we need a Linus Torvalds version 2.0 to build a free open-source P2P Beowulf cluster over the Internet.

Imagine playing Doom 3 on a P-II, with the graphics being rendered by an Athlon64 somewhere in the Internet.

Now that many computers are connected to the Internet with fast DSL connections, it would be very beneficial for all if someone could start such a project.

The basic software already exists and it is in the public domain: MPI.

I explain this idea in more detail on my blog.

No Salt water does not freeze, the ICE is mostly Fresh water and rocks and dirt maybe.
check this link for an explaination

There are very low delta-v paths between points in the solar system. These are known as the interplanetary superhighway. You'd throw the baseball at a very specific speed and direction, it would enter a slightly different orbit, and gradually, over the course of very many orbits it would interact harmonically with the moon's orbit, widening it's orbit slightly on each pass. Eventually, it would pass through an unstable Lagrange point, and have a wide variety of paths to choose from, including paths that wound up in Lunar orbit. These paths are very slow, but useful to unmanned probes.

Couldn't let all of Nerull's misinformation stand.

Considering that the Windows platform has never had the ability to parallel compute in the past, it leaves great potential to the company's operating system development. That is not entirely correct. An MPI is working for windows and allow to build really working windows cluster. Me and another person made such a cluster several years ago, it was more difficalt then Linux cluster, but it was working. (Why we did it - we were building cluster for 3d rendering and had to use DirectX API)

'There was a cumulative effect with the canceled flights and trying to get crew assigned that caused the system to be overwhelmed.'

I am only trying to make sense out of the above comment from the official statement above.

Crew assigment is a hard problem, it is usually an MILP (Mixed Interger Linear Programming) .

Such problems may be very hard to solve in reasonable time. Maybe (I'm shooting in the dark here) the first delays made the crew assigment problems grow too large for being solved in reasonable time.This would generate a snow ball effect as the assimgment problems would keep on growing maing the system "crash".

We may never know what really happened but this would be a nice example for my classes :-)

Did you even read the text you quoted? "very, very low". Not zero. We certainly seem to be able to slam them into, say, Mars with uncanny accuracy.

It does makes sense though. A regular mirror only reflects light on one side.

They are often twice as bright as the cars low beams, and when they are on (with the low beams) there is as much or more light coming from the front of the car as with the high beams alone, and are just as blinding to oncoming traffic (or traffic you are following)

If you are refering to fog lights you are greatly mistaken. Legal fog lights are 55 watt bulbs (model H1 infact), equivelent in power to a typical cars low beam. When they are aimed as they should be, they do not shine up at all and will not "blind" anyone. If you are blinded by a factory or aftermarket fog lights that are aimed correctly (much lower then the headlights), you should not be driving at night yourself. Stand about 20 feet in front of a car with the low beams and fog lights on, look at the light patterns on your legs as you walk toward the car. You should clearly see both light beams and where they are aimed. For a better perspective, bend down and look into the lights, you will see the different heights that they are aimed as noted by the extreme brightness change. There is no way the eyes of an oncoming car are that low to the ground.

Here is are two links that debunk your yellow theory also.

I think most folks in the /. world consider IT to be the 'tech' industry. Not surprising due to the backgrounds of the people who read/post here. As for 'tech' jobs, there are quite a few in my region of the technology world:

LLNL has 20 open S&E positions.

INEEL in the middle of transitioning contractors, but will undoubtedly need S&Es to complete missions for DOE and the Navy.

LBL has 95 open S&E positions.

BNL has 7 open S&E positions.

SNL has 20 open S&E positions.

LANL has 107 open S&E positions.

ORNL has 28 open S&E positions.

PNNL has 36 open S&E positions.

ANL has 32 open S&E positions.

There complete list of laboratories is here. All of them have job postings in the S&E categories. These just happen to be the largest insitutions.

I haven't even started searching Monster.com

Actually one of the programs that the DOE and the NRC is working is using depleted uranium mixed with lead and concrete to encase hazardous nuclear waste.

Depleted uranium, while still being slightly toxic, is far more dense than the current lead linings that we use (on the order of no noticable radiation other than the minute levels in the dpu escaping). Plus with a number of years of testing (on the order of 5 to 10 {while not alot, functional to give an estimate of breakdown}) they are finding no leakage from the test "plugs".

The idea is to encase a standard radioactive waste container in this dpu/lead/concrete mixture to form a cube, then stacking them 3-4 high, row after row. Once the facility (like Yucca mountain) is full, use the same mixture to seal the entrance, mark it as possibly hazardous/radioactive and then basically forgetting about it for 5-10 thousand years.

With little or no leakage, the only thing you'd actually have to worry about is erosion.

For more info see Ducrete

it is so funny so here's the clickable link

Ian Foster's definition is here http://www-fp.mcs.anl.gov/~foster/Articles/WhatIsT heGrid.pdf

A book he edited is often considered the an excellent starting point, The Grid: Blueprint for a New Computing Infrastructure. His website http://www-fp.mcs.anl.gov/~foster/

Only reason why I know anything is because I have a 10 page report due before the end of the week for my High Performance Computing module. Yippee.

Ian Foster's definition is here http://www-fp.mcs.anl.gov/~foster/Articles/WhatIsT heGrid.pdf

A book he edited is often considered the an excellent starting point, The Grid: Blueprint for a New Computing Infrastructure. His website http://www-fp.mcs.anl.gov/~foster/

Only reason why I know anything is because I have a 10 page report due before the end of the week for my High Performance Computing module. Yippee.

Not really answering your question, but there is a thing called MPI (Message Passing Interface) which is a cross-platform standard for parallelized programs. You write your program, and it will run on your Beowolf or that massive 24-way Sun, or even locally on you linux box, if written properly. Of course this will always be slower, in the single CPU case, compared code written the old-fashioned way.

Another very important thing to remember is power consumption and cooling. You might be able to get fifty PII's for free, but powering them, cooling them and maintaining them is not free. Our teeny cluster, consisting of 6 PII-350 nodes, one PIII-450 master and a Cisco switch cost my university $200 to run for a month, and that is not counting cooling. Adjust for power costs in your part of the globe, but still damn expensive for, what in effect, was a ~1200 MHz machine.

well then ur a fucktard cuz you can get the iso here, here, and here. And if you'd like, you can even look at this HTML page on Suse's website which shows you the same links.

maybe you should become better informed before you start bitching about something that is clearly the result of your stupidity. loser.

Hmm...aparently the answer is it depends on the medium

Projectile equations of motion, very useful in FPS games.

Biography here and here

I think you mean the speed of electrons. Electrons can't travel the speed of light (in a vacuum)

I know this link has been on /. several times before, but I feel the need to bring it up again. Mars Scorecard

Given the history with our probes, five years does not seem to be a plausible timeline for this goal. However, it may be just the swift kick in the arse that NASA needs.

They've already announced the PSP will have a MemoryStick slot and Sony already sells video recorders that record video onto those. So you can stop hoping and start complaining about Sony's stupid proprietary formats/lock-ins, etc..

Zero-G is a commonly accepted term.

That's because Zero-G is NOT Zero Gravity. Why is that so hard to understand?

http://www.aoe.vt.edu/~cdhall/Space/archives/00074 1.html
http://www.newton.dep.anl.gov/askasci/phy99/phy994 67.htm
http://www.astrodigital.org/space/zgr.html

Sigh, skydiving is ***NOTHING*** like freefall

If you say so. Honestly, you do get complete free fall up until terminal velocity is reached. Not necessarily as long as this ride, but it definitely happens. Same thing with amusement park drop towers. Terminal velocity usually isn't reached by the time they begin the braking procedure.

Yes.

Liquid metal cooling is a popular choice for fast breeders, since molten metals generally have excellent heat conductivity and don't slow down neutrons too much (depending on the metal.) Sodium-cooled designs are more common than lead or lead-bismuth, but sodium reacts violently with water and, if it captures a neutron, becomes a fiercely gamma-active isotope.

... there's this idea, which I've always been rather partial to.

Put the stuff back where it came from. What could be more environmentally conscious?

This is the best I could find.

Someone found a better link for me a few weeks back on slashdot, but I must have lost it. Until then, I'd never heard of it, only knowing about pebble beds. Don't worry let your hippy side worry though, Congress killed IFR a few years back.

Hell, supposedly we wouldn't have to mine more fission fuel for a hundred years, it would be more difficult to use the fuel for weapons than to make your own weapons-grade stuff, and the contrived scenarios where things could go wrong are so absurd that even the fearmongers would have trouble not breaking into a small grin while listening.

Electrons move at about 3cm/s

The speed of the electron is not the speed of the signal. Think of a cardboard tube full of ping pong balls. Stick a ball in one end, it pushes a ball out the opposite end.

10 amps of current in a 1mm copper wire has a drift velocity of about 0.024cm/s. Thats how fast the electrons in the wire are moving. The thermal velocity, however, would be somewhere around 100,000 meters/sec. Thats how fast the signal is moving. And it's really close to c/3 (a third the speed of light).

The bound electron whipping around a hydrogen atom is moving pretty damned close to the speed of light.

Sometimes, electrons can move Even faster than light!

Optical computing may or may not be the future. In theory, quantum teleportation and that kind of crap could propogate even faster than a bunch of photons.

You can find more infomation here and here

Fact is less than 25% of all oil is consumed to fuel our cars and power our homes.

FSVO 'fact.'

In the real world, upwards of 40% of a given barrel of oil ends up as gasoline, and maybe up to 60%. Gasoline. That's used in cars, military vehicles, and small planes. It's not used to power or heat our homes.

The other 75% goes directly to manufacturing, and thus demand will not be significantly reduced by simply adding solar.

Wrong. Plastics and other manufacturing concerns consume the minority of each barrel of crude. Now, granted, if we stop using the lighter fractions of crude to drive our cars, that doesn't mean we can magically turn the whole barrel into heavier stuff suitable for plastics feedstocks, but your numbers are way off.

We have solar panels today nearing the theoretical maximum effeciecy of the substrate used to convert it.

Yeah, and? Next step is to make them cheaper. Or more durable, which basically amounts to the same thing.

Besides, we've already got the technology to move beyond fossil fuels, it's as safe or safer than burning coal, pollutes a helluva lot less, and has enough fuel sitting around to last us practically forever: fission. The only thing lacking is the political will, and the only problem is that people are stupid.

We're pretty good at making twitching metal on the ground. There's actually a place that keeps track of the 'score' if you're interested.

http://www.bio.aps.anl.gov/~dgore/marsscorecard.ht ml

So far we're on the losing team for the earth/mars games. Get used to it. They call this stuff "rocket science" because it's *difficult*.

What we know is that higher income and education reduces number of children.

The question is actually how much people with income approx equal to US or that one in Europe the earth could sustain?

from my memory the estimation was about 10-15 billions people. And estimation of the population we have in hands say that earth population will not exceed 15 billions at least for coming 100 years.

as for sustaining energy for every one of 15 billions. There are alternatives see for example solar power from moon idea.

(Slashdot had an article on solar power energy report to congress last year, later I found the link to report of the author of idea see http://www.worldenergy.org/wec-geis/publications/d efault/tech_papers/17th_congress/4_1_33.asp )

Coupled with possible space elevator http://www.spaceelevator.com/ and new advances in solar panels with higher efficiency such as for example approach here http://www.lbl.gov/Science-Articles/Archive/MSD-fu ll-spectrum-solar-cell.html the paper http://www.lbl.gov/Science-Articles/Archive/assets /images/2004/Mar-24/Multiband%20Semiconductor.pdf it will cost to develop even less than estimated in original suggestion and thus cost of power will be even less.

also even though we are far from fusion power - but nuclear power on fast neutrons ( as we call it here in Russia not sure what is the proper call for the approach in English) ( so not that well known nuclear power stations on slow neutrons but that power stations based on new approaches with greater efficiency) could provide energy for the earth ( with the already known resources of uranium) for 2500 years! ) to reduce nuclear pollution it is possible to use such things as http://www.anlw.anl.gov/htdocs/anlw_history/reacto rs/ifr.html with recycling of nuclear waster.

That is - I think that rather than try to control growth of population it is better to devise and pursue clean ways to get power and provide better living standards for everybody - then there will be less pollution and the growth of population will stop.

Please define "code monkey". I am not a programmer, I am a sysadmin, so I guess I'm already an IT monkey, but what separates a programmer from a code monkey? The ability to generate fractals?

I'll pick this up.
A "code monkey" is a guy who can use the tools, but doesn't know the theory.
It's like the difference between an electrician and an electrical engineer.

If you're in a REAL computer science program there is a LOT of math and theory involved. Take a look at the CS program at my alma mater for example.
LINK


You don't need vector calculus to write an operating system.

Maybe, but you'll need all kinds of discrete math, set theory, etc if you actually want to write a GOOD operating system.

It's kind of like how you don't need to know the simplex method to deliever newpapers, but if you're going to call yourself a "resource allocation exert" you should.

"Google" is based off the word "Googleplex", a very large number.

Googles claim to fame is that they index a large number of pages, although not quite a googleplex (yet). It is not related to the word 'Frugal' in any way I can connect. 'Froogle' seems to be a bastardization of 'Frugal' and 'Google'.

If Google really wanted the domain name gone, couldn't they make a claim of Trademark infringment?