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If you are interested in neutrinos, there's quite a lot going on. Check:
Fermilab's MINOS;
CERN's NGS;
more in general, a page on Neutrino oscillation

I used to work at Argonne and I remember research being done there with this very same thing about 5 years ago or so. I found a couple of old articles on the Argonne site mentioning it:

3-D Science Scene

VIRTUAL REALITY ENVIRONMENT OFFERS NEW INSIGHTS INTO THE DYNAMICS OF COMPLEX SCIENTIFIC PHENOMENA

I used to work at Argonne and I remember research being done there with this very same thing about 5 years ago or so. I found a couple of old articles on the Argonne site mentioning it:

3-D Science Scene

VIRTUAL REALITY ENVIRONMENT OFFERS NEW INSIGHTS INTO THE DYNAMICS OF COMPLEX SCIENTIFIC PHENOMENA

Projector technology right now sucks for the high end. The CAVE uses CRT projectors (much like the ones in the old big screen TV's) instead of a brighter technology such as LCD, DLP, or Digital Light Valve. Unfortunately, the manufacturers of these brighter products have not pushed the refresh rate limit. In order to use the StereoGraphics shutter glasses, you need at least 100 Hz refresh rate out of your projectors. Currently, the only types of projectors that can handle 100 Hz are CRT's.

These CAVE's are not really multiuser. There are some real problems with perspective in these environments. Only one person can have a corrected view frustrum, and everyone else has to put up with a warping and shearing scene. Of course, this is assuming you are trying to visualize something floating in front of you. This is very hard to describe, but if you think about it, imagine projecting an object floating in front of you, while trying to give your user the ability to walk all around it. Anyhow, this is impossible in any multiuser mode.

CAVE are small. 10'^3 may seem like a lot of space, (as most people's dorm rooms are 12'^3), but oftimes people are limited in movement. This also limits the number of people who can share this experience.

The Electronic Visualization Lab at University of Illinois, Argonne National Labs Futures Lab, and NCSA all have major research going on in CAVE technology.

-Stryemer
We are the music makers,
and we are the dreamers of the dream.

CAVE Quake2.

It may not solve all the problems, but it is a beginning.

In short, the CAVE is a room-sized projection-based VR system. I am fairly certain it was pioneered at Argonne National Labs. (BTW, they have a *very* interesting Linux supercomputing project going on with IBM and VA Linux Systems).

Check out the CAVE Quake2 site for details (technical info, screenshots, movies!), etc.

Hit Related Sites for more info on the CAVE.

Nothing can possiblai go wrong. Er...possibly go wrong.
Strange, that's the first thing that's ever gone wrong.

http://www-unix.mcs.anl.gov/~evard/chibacity/

This looks wonderfull... Send a note of support to info@anl.gov or the lead guy on the IBM side, tfiggatt@us.ibm.com...

These guys are not only doing stuff that is fun to look at, they are willing to let people work on their own projects within their project... Drop them a note...

Sorry. 's where I work, though not with anything as groovy as biochips. : (

Anyway, there's a blurb about this on the Argonne home page, here. Probably not a lot more informative than the above link, but it's got a hokey graphic (oooh! pictures!).

--

http://www-unix.mcs.anl.go v/~michalak/ecmwf98/final.html, Design of a Next-Generation Regional Weather Research and Forecast Model

http://nic.fb4.noaa.gov:800 0/research/wrf.98july17.html, Dynamical framework of a semi-Lagrangian contender for the WRF model

A few other thoughts:

1. Not only are the Alpha 264s unmatched in terms of both floating point performance and memory bandwidth (although the next-generation PPC is very good in that regard also), they are also among the best at dealing with the data-dependencies and access-latencies which occur in real scientific codes.
2. DEC^H^H^HCompaq probably has the best compiler technology of anybody out there commercially (IBM are also very good technically, but as Toon Moene of the Netherlands Met Office put it, "XLF was the first compiler I ever encountered that made you write a short novel on the command line in order to get decent performance."
3. Note for AC # 68 State-of-the-art weather models are not spectral models. Spectral models are appropriate only for very coarse scales at which cloud effects are only crudely parameterized (and to some extent are only appropriate on vector-style machines (and not current microprocessor/parallel) because of the way they generate humongous vector-lengths). At the WRF scales, the flow is not weakly compressible! Note that the global data motion implied by the FFTs in hybrid spectral/explicit models is a way to absolutely kill scalability for massively parallel systems. Finally, spectral models do not support air quality forecasting, such as we are doing (see http://envpro.ncsc.org/projects/NAQP/).
4. Weather modeling is a problem which has exponentially-growing divergence of solutions (two "nearby" initial conditions lead to different solutions that diverge exponentially in time), so as coyote-san suggests, there is a tendency to run multiple "ensemble" forecasts, each of which is itself a computationally-intense problem. So far, I haven't managed to get the funding to develop a stochastic alternative (which will be a fairly massive undertaking -- any volunteers?) This means weather modeling can soak up all avaailable CPU power for the (foreseeable)^2 future. At least the individual runs in ensemble forecasts are embarassingly-parallel.

Hi, Greg! Didn't know you were here!

One thing I find sorely lacking in many books on algorithms is any discussion of why you would select one over another

Do you mean GA versus say a Newton search method? GA is sometimes referred to as a method of last resort. This may be unfair, because many practical problems are not mathematically "nice". I am just getting into GA and I have very complicated simulations underlying my objective functions. We previously computed derivatives for these; it was a huge effort both computationally and for the programmer. One thing that I like about GA is that wrapping the optimizer around an arbitrarily complex objective function is really easy. Also, the parallelism is really good ("embarassing"), especially for distributed computing with message-passing (think beowulf).

For me, the bad thing is that convergence isn't nice and quadratic like some derivative based methods out there. On the other hand, quadratic convergence generally works only near the optimum and derivative based optimizers really only find local minimums (no guarantees about the optimum being globally optimal). Derivative based methods can blow up if you pick a bad guess objective too. Perhaps a good strategy is a combination -- use GA to get into the neighborhood of the global optimum and then use derivative based methods to find it.

I should stress that all this is for my particular application (groundwater). YMMV. Others with different objectives living in differently constrained control spaces will have different experiences. Also, to be fair I should point out that programs like ADIFOR make derivative computations easy to program.

Some helpful optimization links:

Decision Tree for Optimization Software

GA Archives

i quote from the beowulf mailing list faq v2 at: http://www-unix.mcs.anl.gov/~utha yopa/bwfaq2.html

2. Where can I get the Beowulf software? [1999-05-13]

There isn't a software package called "Beowulf". There are, however, several pieces of software many people have found useful for building Beowulfs. None of them are essential. They include MPICH, LAM, PVM, the Linux kernel, the channel-bonding patch to the Linux kernel (which lets you 'bond' multiple Ethernet interfaces into a faster 'virtual' Ethernet interface) and the global pid space patch for the Linux kernel (which, as I understand it, lets you see all the processes on your Beowulf with ps, and maybe kill etc. them), DIPC (which lets you use sysv shared memory and semaphores and message queues transparently across a cluster).

As for the licensing info, presumably the patches to the Kernel will be GPL'ed. Check out: http://www.beowulf.org/software/softw are.html. I couldn't find any specific information on liscensing, although they do refer to the software necessary to implement Beowulf as:

implemented as an add-on to commercially available, royalty-free base Linux distributions

hope this helps
alex

Some of the more interesting pieces, like LSF, are only licensed by Sun, thus will not be included in this `deal.' (For a free improvement over LSF, check out GNU Queue. If it doesn't do something you want, you can support the community and extend it.) If you read the announcement carefully, you'll see that the only new codes to which it applies are the parallel file system (the Sun CTO thinks distributed file systems are dead, anyways), the Prism debugger, and the parallel run-time environment.

Of those, the only with no available substitute is the debugger. The ROMIO library is a good place to start for the MPI file I/O stuff (a good database would be a better place, imho). I already mentioned queue management software. The Ptools Consortium and the Globus Project have links to other HPC cluster tools.

Many of the pieces for debugging are available (combine ddd and gnuplot), but some notable ones are missing. The ability to control multiple GDBs easily from one processes and the visualization of parallel execution are needed, and quite difficult to implement. There seems to be interest in making GDB easier to use from other processes, which is a good start towards solving the larger problem of general, distributed debugging. And both the mpich and LAM MPI implementation have some profiling information, but few tools to dig through it.

To be fair, Sun has contributed (and supported contributions) to the original packages. Why they are releasing the rest under their Exploit the Community license is beyond me.

Jason, ejr@cs.berkeley.edu

Some of the more interesting pieces, like LSF, are only licensed by Sun, thus will not be included in this `deal.' (For a free improvement over LSF, check out GNU Queue. If it doesn't do something you want, you can support the community and extend it.) If you read the announcement carefully, you'll see that the only new codes to which it applies are the parallel file system (the Sun CTO thinks distributed file systems are dead, anyways), the Prism debugger, and the parallel run-time environment.

Of those, the only with no available substitute is the debugger. The ROMIO library is a good place to start for the MPI file I/O stuff (a good database would be a better place, imho). I already mentioned queue management software. The Ptools Consortium and the Globus Project have links to other HPC cluster tools.

Many of the pieces for debugging are available (combine ddd and gnuplot), but some notable ones are missing. The ability to control multiple GDBs easily from one processes and the visualization of parallel execution are needed, and quite difficult to implement. There seems to be interest in making GDB easier to use from other processes, which is a good start towards solving the larger problem of general, distributed debugging. And both the mpich and LAM MPI implementation have some profiling information, but few tools to dig through it.

To be fair, Sun has contributed (and supported contributions) to the original packages. Why they are releasing the rest under their Exploit the Community license is beyond me.

Jason, ejr@cs.berkeley.edu

Some of the more interesting pieces, like LSF, are only licensed by Sun, thus will not be included in this `deal.' (For a free improvement over LSF, check out GNU Queue. If it doesn't do something you want, you can support the community and extend it.) If you read the announcement carefully, you'll see that the only new codes to which it applies are the parallel file system (the Sun CTO thinks distributed file systems are dead, anyways), the Prism debugger, and the parallel run-time environment.

Of those, the only with no available substitute is the debugger. The ROMIO library is a good place to start for the MPI file I/O stuff (a good database would be a better place, imho). I already mentioned queue management software. The Ptools Consortium and the Globus Project have links to other HPC cluster tools.

Many of the pieces for debugging are available (combine ddd and gnuplot), but some notable ones are missing. The ability to control multiple GDBs easily from one processes and the visualization of parallel execution are needed, and quite difficult to implement. There seems to be interest in making GDB easier to use from other processes, which is a good start towards solving the larger problem of general, distributed debugging. And both the mpich and LAM MPI implementation have some profiling information, but few tools to dig through it.

To be fair, Sun has contributed (and supported contributions) to the original packages. Why they are releasing the rest under their Exploit the Community license is beyond me.

Jason, ejr@cs.berkeley.edu