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Your company should pool resources with the other 30 or so victims and sue to invalidate the patents and for damages.

As for ANYone claiming to have invented anything having to do with the use of text, images and forms on the internet for ANY purpose, I think Tim Berners-Lee and the people at CERN might have a little tiny bit to say about *cough* prior art *cough*.

But there is a C/C++ interpreter.

This is a difficult question to answer, but the answer is full of totally unrelated semi-googlewhacks and curious links.

Usually (but not always) only a problem when you are doing server side work but RWCString uses copy on write (see here). You have to muck around with the mutex pool size to really get this to work though...

Ask and ye shall receive!

This is not a pointless experiment. In both experiments that the article mentions (SNO and SuperKamiokande) neutrinos are produced by a natural process (either nuclear reactions in the Sun or cosmic rays in atmosphere). There is always a possibility that we don't understand these natural processes good enough and that we misinterpret the data.

In these planned terrestrial neutrino oscillation experiments (such as NOMAD, K2K, OPERA, MINOS, etc.) neutrinos will be produced in controlled reactions on Earth, making interpretation and measurements easier, more precise and more model-independent.

This is not a pointless experiment. In both experiments that the article mentions (SNO and SuperKamiokande) neutrinos are produced by a natural process (either nuclear reactions in the Sun or cosmic rays in atmosphere). There is always a possibility that we don't understand these natural processes good enough and that we misinterpret the data.

In these planned terrestrial neutrino oscillation experiments (such as NOMAD, K2K, OPERA, MINOS, etc.) neutrinos will be produced in controlled reactions on Earth, making interpretation and measurements easier, more precise and more model-independent.

Quark stars are a new and interesting idea, but quark matter in general is not a new idea. "Quark matter", more usually "quark plasma" or "quark-gluon plasma", is believed to be the dominant form of matter in the universe just following the big bang. There is also early evidence that it's been witnessed in some of the largest particle accelerators.

In normal matter quarks group together in sets of 3 to form protons and nuetrons. Rare particles, like pions, can be formed from pairs of quarks, but quarks never appear in isolation, for them it's always in groups of 2 or 3. In quark plasmas though there aren't any distinct groups of twos and threes. All the quarks are smushed into a single substance with arbitrarily large numbers of quarks.

One analogy is if atoms are built out of "solid" quarks (in the from of protons and nuetrons), then the quark plasma is like melting them so they all run together. Prior to this announcement the only time that quark plasmas were expected to appear was in the presence of extraordinarily high energies and temperatures.

We could predict that nuetrons stars should exist because the "nuetron degeneracy pressure" which makes them possible was well understood theoretically. The theory that governs quark interaction is known as quantum chromodynamics and is far more complicated. I'm not sure whether anyone knows how to apply it to massive collapsing stars, and it doesn't surprise me if no one ever tried. It will be interesting to see if the existing theory can be made to justify quark stars. If not, well that's when things really start to get exciting.

Only projects that easily comes to my mind for using such a technology is CERN's LHC project. Though it seem that this one is still inadequate for their purposes. Promising development in any case. Some numerical information on LHC computational challence.

Only projects that easily comes to my mind for using such a technology is CERN's LHC project. Though it seem that this one is still inadequate for their purposes. Promising development in any case. Some numerical information on LHC computational challence.

Has anyone been able to download the Carrot tarball? The FTP server gives me "Login incorrect" when I try to login as anonymous user.

Or maybe even a few scientists at CERN...

Cheers,
Ian

http://press.web.cern.ch/livefromcern/antimatter/f actory/AM-factory04-b.html

says that they just let the things anhiliate.

It may be just my opinion (as a former chemist turned physicist), but I think that chemists are rather limited. They're (in general) not very well versed in technological issues and the hard science -- I've found that they're usually an "end-user" of other disciplines' accomplishments.

In actuality, old systems like the CDC6600s used to have very similar constraints, where reordering instructions could give you signifigant performance improvements. Quoting from here

The 6600 CP had an 8-word instruction stack which functioned rather like an instruction cache, but without the flexibility of a modern cache. Program optimization consisted of allocating heavily used variables to registers, loading operands from memory a few instructions before they were needed, writing operands to memory a few instructions before their registers were needed to hold new operands, keeping several functional units busy simultaneously, and trying to get inner loops to fit into the instruction stack. The divide instruction was notorious, because it took about thirty clock cycles and its functional unit was not pipelined. The peak CP instruction rate was one instruction every 100 nanosecond clock cycle.

Of course, you can theoretically do better by doing it in the compiler than you can in the assembler, but you can easily get the first 80%.

Also, the GEANT 4 toolkit from CERN is used for high-energy physics simulations and is OO-C++
Geant 4

With Exchange 2000, you are really looking for the ADSI scripting interface to ActiveDirectory - as the Exchange DS is merged into AD. Check out Microsoft Technet.

replies pointing me to CERN webpages.

Here you go.

Also try the ROOT package. It's also developed at CERN (by the PAW people) but is in C++ (with a built in C++ interpreter) and has much more to it than PAW.

It's aimed at the Particle Physics community but is currently in use in a wide range of fields from Astronomy to banking!

Oh yes, runs on Linux and Windows...

Developed at CERN
Great for graphical representation, and statistics. Released under GPL.

I remember using it about three years ago under Red Hat for reconstruting cosmic ray showers. Can't see any possible problems with Debian...
It was great for what I was doing.

Matt.

let's see. 1 GB in 10 ms works out to 100 GB per second. how recently did GB ethernet come about? and what would the average bandwidth of users be? i would guess much less, but let us assume 100KB per second.

Well 100 GB per second is the raw data rate, as read out (heavily parallel) from the detector, i.e. the data rate the DAQ (Data AQuisition) system has to keep up with. That's pretty difficult really, but done completely in hardware: the readout chips have relatively large on-chip buffers for each read-out channel. NOST OF THIS DATA IS DISCARDED RIGHT AWAY from the so-called Level 1 Trigger, whose purpose is to throw away the most obviously uninteresting collisions.

Since the data rate after L1 is still WAY too large to be all stored, another trigger, unimaginatively called Level 2 Trigger, sorts out even more crap. Since the data rate is lower than for L1, L2 can use more sophisticated algorithms to figure out which event is crap and which is an ever-famous Higgs decay :-)

One more trigger, Level 3 (you guessed it), is used to even further reduce the amount of data, again with more sophisticated means.

Still, the required bandwidth is quite impressive. At CDF II, the data rate after Level 3 will be about 75 events per second, at half a meg each, summing up to 30-40 MB per second (well enough to saturate Gbit ethernet), which are all reconstructed right away.Note that for the LHC experiments (CMS, ATLAS) the amount of data is more than an order of magnitude larger than for CDF and D0 (at Fermilab).

The LHC data will be spread all over the world, using a multi-tier architecture with CERN being Tier 0, and national computing centers as Tier 1 centers, universities being Tier 2, etc. No national computing center will be able to store ALL data, so the idea is that e.g. your Higgs search will be conducted on the U.S. Tier 1 center, B physics on the German Tier 1 center and so on. Obviously not only US scientists will search for the Higgs, so others will also submit analysis jobs on the US Tier 1 and vice versa. To get this working, the GRID is designed. A current implementation is GLOBUS.

Having said this, it is important to note that right now, the GRID is nowhere near this goal. To submit jobs in this "fire and forget" way is not possible yet. There is a shitload of problems to yet solve, the most important ones: trust and horsepower.

Trust: you must allow complete strangers to utilize your multi-million dollar cluster, and they haven't even signed a term-of-use form.

Horsepower: everybody expects to get more CPU cycles out of the GRID than he/she contributes. Obviously, this will not work. (Albeit the load levveling might improve the overall performance.)

let's see. 1 GB in 10 ms works out to 100 GB per second. how recently did GB ethernet come about? and what would the average bandwidth of users be? i would guess much less, but let us assume 100KB per second.

Well 100 GB per second is the raw data rate, as read out (heavily parallel) from the detector, i.e. the data rate the DAQ (Data AQuisition) system has to keep up with. That's pretty difficult really, but done completely in hardware: the readout chips have relatively large on-chip buffers for each read-out channel. NOST OF THIS DATA IS DISCARDED RIGHT AWAY from the so-called Level 1 Trigger, whose purpose is to throw away the most obviously uninteresting collisions.

Since the data rate after L1 is still WAY too large to be all stored, another trigger, unimaginatively called Level 2 Trigger, sorts out even more crap. Since the data rate is lower than for L1, L2 can use more sophisticated algorithms to figure out which event is crap and which is an ever-famous Higgs decay :-)

One more trigger, Level 3 (you guessed it), is used to even further reduce the amount of data, again with more sophisticated means.

Still, the required bandwidth is quite impressive. At CDF II, the data rate after Level 3 will be about 75 events per second, at half a meg each, summing up to 30-40 MB per second (well enough to saturate Gbit ethernet), which are all reconstructed right away.Note that for the LHC experiments (CMS, ATLAS) the amount of data is more than an order of magnitude larger than for CDF and D0 (at Fermilab).

The LHC data will be spread all over the world, using a multi-tier architecture with CERN being Tier 0, and national computing centers as Tier 1 centers, universities being Tier 2, etc. No national computing center will be able to store ALL data, so the idea is that e.g. your Higgs search will be conducted on the U.S. Tier 1 center, B physics on the German Tier 1 center and so on. Obviously not only US scientists will search for the Higgs, so others will also submit analysis jobs on the US Tier 1 and vice versa. To get this working, the GRID is designed. A current implementation is GLOBUS.

Having said this, it is important to note that right now, the GRID is nowhere near this goal. To submit jobs in this "fire and forget" way is not possible yet. There is a shitload of problems to yet solve, the most important ones: trust and horsepower.

Trust: you must allow complete strangers to utilize your multi-million dollar cluster, and they haven't even signed a term-of-use form.

Horsepower: everybody expects to get more CPU cycles out of the GRID than he/she contributes. Obviously, this will not work. (Albeit the load levveling might improve the overall performance.)

Nevertheless, its primary developers are Rene Brun and Fons Rademakers (familiar names from the old days), and at least one crucial bit of code (the MINUIT minimization engine) has been run through f2c and recycled, so it's not fully independent. Seriously, it would be very useful if someone were to rewrite MINUIT in an intelligible style.

Of course, this was probably salescrap. Does anyone know the truth on this?

The BABAR experiment at SLAC is using Objectivity for data storage. Unfortunately, I cannot find a publicly available web page about computing at BABAR right now.

The amount of data BABAR produces is in the order of magnitude of 10's of terabytes per year (maybe a hundered), and even storing this amount in Objectivity is not without problems. The LHC, which is currently under construction, will generate much more data than BABAR, but even if they reach 10 petabytes per year one day, I very much doubt that they will be able to store this in Objectivity.

Now, add another bit, and you have to use a trinary distribution, which I'm sure exists but isn't very common (and not surprisingly, I can't recall that one either).

Well, I don't think that the probability is really much worse. Instead of binomial, we have in general multinomial, and here trinomial: pdf=(n!/(x_i!*x_j!*x_k!))(p_i^{x_i}*p_j^{x_j)*p_k^ {x_k)).
See Berger's Statistical Decision Theory and Bayesian Analysis. Or here or here.

There are some hardware problems; I posted a possible solution . (It's a joke, mostly!)

A more serious problem is mentioned by anohter poster: floating point is where we really, really care about speed and efficiency, and it seems that binary has that sewn up.

... we'll never see large scale use of ternary computing. There's just too much overhead involved in switching over the way of doing things at such a fundamental level.

Quite right. This is the only argument against it which doesn't have an answer, I suspect.

In many present and (not so far) future experiments in HEP we deal with this kind of data rate. A nice overview can be found here here.

On page 14 you can find the data valume. It is at about 100 TB for present experiments (I am with BaBar).

page 25 gives some overview on the hardware we use at BaBar/SLAC (e.g. farms of STK Powderhorn tape silos with 6000 tapes each, etc..).

page 95 gives an overview on data rates. ATLAS records at 100Hz and 1MB per event, i.e. 100MB/s

Page 99 gives overview of the (estimated) costs of hardware and tapes for LHC experiments. They are in the order of 20 MCHF (Mega Swiss Franks ~ 0.8 Mega Dollar) initial + 10 MCHF per year. We use a mixture of large RAID farms and tape silos. Everything is managed by HPSS (High Performance Storage System). From my experience at BaBar I can tell you that these numbers are underestimated by at least a factor of 2.

In many present and (not so far) future experiments in HEP we deal with this kind of data rate. A nice overview can be found here here.

On page 14 you can find the data valume. It is at about 100 TB for present experiments (I am with BaBar).

page 25 gives some overview on the hardware we use at BaBar/SLAC (e.g. farms of STK Powderhorn tape silos with 6000 tapes each, etc..).

page 95 gives an overview on data rates. ATLAS records at 100Hz and 1MB per event, i.e. 100MB/s

Page 99 gives overview of the (estimated) costs of hardware and tapes for LHC experiments. They are in the order of 20 MCHF (Mega Swiss Franks ~ 0.8 Mega Dollar) initial + 10 MCHF per year. We use a mixture of large RAID farms and tape silos. Everything is managed by HPSS (High Performance Storage System). From my experience at BaBar I can tell you that these numbers are underestimated by at least a factor of 2.

a quick search came up with

iCal 3.5
A very dynamic calendar utility that allows you to post dates on your Intra/Internet. November 3rd, 2000 Shareware 1.5MB win32

http://www.brownbearsw.com/ical/icalpage.html

ICal 2.2
ICal is a popular X-based calendar and scheduler application. September 28th, 1998 256.6K

http://wwwinfo.cern.ch/pdp/ose/asis/products/TCL/i cal-2.2/ical.html/

JetSync 1.0
Synchronizes your email, calendar (ical), memos and addresses and enables conduits for other types of data. February 22nd, 2000 GPL 213.3K
(I could not find the webpage but palm links to it)

http://mega.ist.utl.pt/~frias/jetsync/

Syncal 0.5
Syncal reads a current ical calendar file, an archived ical calendar file, and a Palm(TM) device DateBook database. April 12th, 1999 GPL 26.1K

http://hopf.math.nwu.edu/syncal/

lib ICAL 0.23
Lib ICAL is an open source implementation of the IETF's iCAL Calendaring and Scheduling protocols. March 28th, 2001 MPL 567.9K

http://hopf.math.nwu.edu/syncal/

yes I think that there is a lack of servers you can build yourself

companys often want to run servers on their intranet and dont want to far it out to a outside source (palm sells alot of their enterprise servers which do syncing)

personally the only app that runs this well and gets messaging right has been Lotus Notes Domino

frankly it rocks and I am surprised that Ximian have not picked up on this they have a client but no server and the server is where the money is !!

regards

john jones

http://www.ibiblio.org/obp/electricCircuits/

Here is a partial list of books published online, that I happened to like enough to bookmark. I find that reading a book on the computer screen is tedious, I mostly use the online version as a reference.

Handbook of applied cryptography: http://www.cacr.math.uwaterloo.ca/hac/

Underground: (I actually haven't read this yet) http://www.underground-book.com/

Netizens: (only partly read this) http://www.columbia.edu/~hauben/netbook/

http://www.und.nodak.edu/org/crypto/crypto/army.fi eld.manual/

Big Breach: http://www.antioffline.com/bigbreach/

The Prof's Book: http://frode.home.cern.ch/frode/crypto/Turing/inde x.html

I have a lot of other links also, but my bookmarks have become so nested and folderized that many are lost in there, I really need bookmarks for my bookmarks . . . Anyway, I would suggest that if you find yourself looking for interesting reading online, you will find plenty. If you choose you can find scanned in pdf's of various works on newsgroups and in freenet, etc.

However, my advice is to use the 'net primarily as a way to figure out what to read, and become familar with the local public library. Almost all libraries have inter-library loans which give you access to huge amount of stuff. When I can't get a work that way, I fall back upon checking databases of used bookstore inventories -- http://abe.com/ and http://powellsbooks.com/ are the places I generally go to.

There are links to many downloadable simulations here, including an Abwehr Enigma sim for Windows. There even appears to be one written for Palm Pilot.

Java is most certainly used in a number of mathematically-intensive applications. See CERN's Colt library, for example. Quite useful, asshole .

Now let's see...
1. Java is far too slow.--no, it's not. Stupid Java is slow, but you shouldn't be writing Java if you're stupid.

2. All the math libs are already written in Fortran and C, and nobody wants to port.--right, except CERN and a veritable half-ton of other nobodies. Be way of all those "two-dimensional matrix" libraries out there, though. Most suck, like you.

3. Most scientists are not fancy programers and don't care too much about OO, garbage collection, and other frills.--I see. Then I must work with some damn rare, unusual scientists. Or maybe it's just that you don't know what you're talking about.

The End, Hooray!

I've been wondering about this, and I'm not so sure Java will even stay out of the "optimized stuff" for long, either. E.g., COLT JavaNumerics

I think this may be a case where a bit more thinking and literature research about the problem would help a great deal.

We're looking at using MINUIT, a package written by the computing divsion at CERN, as our fitting engine. MINUIT's algorithms are quite advanced, and it's commonly recognized within the physics community as the best general-purpose fitting package out there.

I think you may not realize how complicated the functions we're trying to fit are. Here's the quick and simple version: we study magnetic fields within superconductors and semiconductors on a microscopic level. We do this by using spin-polarized muons or radioactive light ions as a probe, and measuring anisotropy of the emitted decay products. That data then has to be compared against complex models of superconductivity. The computationally expensive part here is calculating the values predicted by the model for a given set of parameters. This has to be done once for each data point to calculate chi-squared, and repeated many times (once in each iteration of the fitting process), each time with different parameters. The models typically contain difficult integrals which must be evaluated numerically thousands of times with very high precision.

Since the function we're trying to fit changes fairly often depending on the sample and measurement techniques used, it's not practical for us to spend huge amounts of time optimizing each individual function to be fitted. The fitting package is already optimized, so the only thing left is to parallelize it.

I think this may be a case where a bit more thinking and literature research about the problem would help a great deal.

We're looking at using MINUIT, a package written by the computing divsion at CERN, as our fitting engine. MINUIT's algorithms are quite advanced, and it's commonly recognized within the physics community as the best general-purpose fitting package out there.

I think you may not realize how complicated the functions we're trying to fit are. Here's the quick and simple version: we study magnetic fields within superconductors and semiconductors on a microscopic level. We do this by using spin-polarized muons or radioactive light ions as a probe, and measuring anisotropy of the emitted decay products. That data then has to be compared against complex models of superconductivity. The computationally expensive part here is calculating the values predicted by the model for a given set of parameters. This has to be done once for each data point to calculate chi-squared, and repeated many times (once in each iteration of the fitting process), each time with different parameters. The models typically contain difficult integrals which must be evaluated numerically thousands of times with very high precision.

Since the function we're trying to fit changes fairly often depending on the sample and measurement techniques used, it's not practical for us to spend huge amounts of time optimizing each individual function to be fitted. The fitting package is already optimized, so the only thing left is to parallelize it.

Linux is a reimplementation of UNIX. The whole GNU tool suite is basically reimplementations of the UNIX Programmer's Workbench from the 1970s. "vi", claimed by some to be innovative, is a reimplementation of an overpriced product called the RAND Editor. X windows is a second system approach to the early UNIX window systems.

During the brief period that Linux companies had money, we didn't see much vision, either. Nobody came out with a desktop system that looked good and was easy to use. Nobody got a top graphic designer and a top interaction designer (yes, there are such people, and you should know who they are) to rework the user interface. The open source industry blew its chance to take on Microsoft.

That's the real problem.

Tully and co-workers have combined the data from the four experiments at LEP and found evidence that the Higgs boson has a mass of 114.9 GeV c-2. 'It is a 2.6 sigma effect,' he told PhysicsWeb, 'so there's still a 6 in 1000 chance that what we are seeing are background events, rather than the Higgs.'

The international physics community gives its golden stamp of approval for the existence of a particle is, I believe, 1 in 10 000, and the LEP at CERN would probably have been able to get that accuracy within a year or two had it not been dismantled for something even bigger.

It will take the detectors on the Tevatron beam, CDF and D0, years with full luminosity to collect the statistics for a five-sigma discovery, and only in a very limited range of the Higgs mass (details). (The Higgs mass is unknown, but the latest limits from the LEP Higgs working group suggest that it's heavier that 110 GeV.)

Chances for LHC aren't really that bad. Their luminosity will be way higher than Tevatron's.

That is of course, if the Higgs exists. If not... well, particle physics will have a very interesting time then :)

It will take the detectors on the Tevatron beam, CDF and D0, years with full luminosity to collect the statistics for a five-sigma discovery, and only in a very limited range of the Higgs mass (details). (The Higgs mass is unknown, but the latest limits from the LEP Higgs working group suggest that it's heavier that 110 GeV.)

Chances for LHC aren't really that bad. Their luminosity will be way higher than Tevatron's.

That is of course, if the Higgs exists. If not... well, particle physics will have a very interesting time then :)

I agree that C/C++ is not the best choice for a scripting language in general, but it does allow one to prototype fast.

This is not the first song about the internet. There has been a song about the web for years.

Just my little rant for the day...

That's why there's a provision for disabling X forwarding. Other things to do to help close down the hole are having your 'ssh' X NOT connect back to your real X server, but to an XNest or mxconns instead.

I don't know exactly how it will compare in price to other solutions, but it was intended to be low-cost. I used it to get a lecture from a prof when he had to head over to CERN once; we were all entirely too distracted by playing with the cameras, but it worked very well. We didn't use the whiteboard, though, just the "point camera at blackboard" method.

Even better- I poked around a bit, and it looks like they might have an installation over at U of M that you could check out, though it's not clear they're still using it. Good luck. Congrats on the position!

....that nobody moderaded up the right answer. The right answer is info.cern.ch which was , at the time, Tim Berners-Lee NeXT Cube machine. It is, at least, the oldest www site ever.

On Tim's book "Weaving the Web" which I believe was featured here on Slashdot, Tim answers that particular question.

(And I just can't believe how many think the web was a NCSA invention)

I know that this isn't terribly helpful, but I actually found this out a few months ago. The bummer is that I can't find it again. It was a page affiliated with Tim Berners-Lee or the W3C. (Or was it on CERN's site?) But it was the #1, very first, no-question-about-it page on the web. It exists. It's out there. Anybody know where?

-Waldo

The first web page was info.cern.ch or nxoc01.cern.ch, this was the page maintained by Tim Berners-Lee and Robert Cailliau, It ran on Tim's Next computer and was served by the first web server also writen by Tim on his Next computer.

Just have a look at this image from the construction of the Superkamiokande Neutrino Detector. The photomultiplier tubes ("mushrooms") used there are very much similar to those used for the AMANDA detector. You can see two of the AMANDA sensors here, together with the glass pressure globes they're put in before deployment.

I know this - have been working for the AMANDA group once, when we were calibrating the first PMT's for AMANDA back in 1995. It's done at Desy Zeuthen near Berlin. And we were using Linux boxes in the lab for data aquisition purposes ;-)

The nifty thing about AMANDA aren't the PMT tubes but the pressure globes they are put in (1500m of solid ice do exert some force ...). I've got one of the predecessors (used for the BAIKAL experiment) at home, it's cool telling people at a party that the salad bowl has once been at 1500m depth in Lake Baikal.

By the way, did someone notice that the AMANDA logo is a Penguin ?

There is another school of thought that believes earth's temperature, and even weather (clouds, to be exact), is affected by Sunspots.

Sunspots increase the Sun's magnetic field which acts as a kind of barrier helping to protect the Earth from cosmic rays. This acts as insulation and increases the Earth's overall temperature. When there are fewer Sunspots on the Sun's surface, it's magnetic field reduces allowing more cosmic rays to reach the Earth which cools the Earth. For example, in the late 17th century, there was hardly any Sunspot activity on the Sun's surface. This period coincided with the "Little Ice Age" when rivers on the Earth remained frozen all year round.

This research is on-going. At CERN, for example, tests are being undertaken with the particle accelerator to see if cosmic rays can affect cloud formation.

What this all means is that our predictions about global warming due to the Greenhouse Effect may have been greatly exaggerated.

----------------------------

> Is this actually true? References? As far as
> I've heard, the rotor configuration was
> parametrable, and indeed changed regularily.

The Enigma did use keys, which was starting position of the n number of rotors. Various Engima models had different numbers of rotors.

Furthermore there is the wiring of the plugboard in the front.

See German Enigma Cipher Machine and Frode's Crypto Page more details about the Engima including simulators.

There's a neutrino beam at CERN (north of the Alps) sending neutrinos which get detected in southern Italy 6km deep inside the Gran Sasso mountain.

ms