Slashdot Mirror

Any theory that attempts to explain the inverse temperature problem must also grapple with the fact that the solar wind continues to accelerate even as it passes the planets! There is no satisfying explanation for that one to date without consideration of an electric field, and the standard solar model miserably fails in explaining it. And this is no minor matter either because the solar wind, taken as a whole, constitutes the largest structure in our solar system, the heliospheric current sheet. Contemplate the implications of that for a moment: astrophysicists do not understand what is causing the motions of the largest structure in our own immediate neighborhood!

(pln2bz; source: http://slashdot.org/comments.pl?sid=426528&cid=22144600; emphasis in the original).

"the solar wind continues to accelerate even as it passes the planets!" BUSTED http://slashdot.org/comments.pl?sid=426528&cid=22148864, http://slashdot.org/comments.pl?sid=426528&cid=22148128

(APODNereid; source: http://slashdot.org/comments.pl?sid=426528&cid=22208390).

Not quite; see http://slashdot.org/comments.pl?sid=426528&cid=22279668. Admittedly, however, the original statement, if enthusiastic, is also imprecise.

(leokor; source: http://slashdot.org/comments.pl?sid=426528&cid=22279804; emphasis added).

If you know of even one observation that doesn't square with Peratt's model of galaxies, by all means, let us know. For Peratt's model, see:
A. L. Peratt. Evolution of the Plasma Universe I. Double Radio Galaxies, Quasars, and Extragalactic Jets. IEEE Transactions in Plasma Science, PS-14, 6 (1986)
A. L. Peratt. Evolution of the Plasma Universe II. The Formation of Systems of Galaxies. IEEE Transactions on Plasma Science, PS-14, 6 (1986)

(leokor; source: http://slashdot.org/comments.pl?sid=426528&cid=22284506; emphasis added).

How about this: "Bright Spiral Galaxy M81 from Hubble" (http://antwrp.gsfc.nasa.gov/apod/ap070529.html) - note the asymmetric arms, the large central bulge;
or this "One-Armed Spiral Galaxy NGC 4725" (http://antwrp.gsfc.nasa.gov/apod/ap050901.html)?

To this day, Peratt's model remains the only one that explains the shape and stability of galaxies, and does it without recourse to such ad-hoc devices as dark matter.

(source as above; emphasis added).

Even in 1986, and allowing for enthusiasm, this remains ... imprecise.

For starters, the MOND folk (Milgrom, Sanders, McGaugh, etc) would no doubt take strong exception to the "without recourse to [...] dark matter" part (http://www.astro.umd.edu/~ssm/mond/).

Next, even in 1986, the observed "shape" of Double Radio Sources associated with Active Galactic Nuclei (DRAGNs) was inconsistent with the Peratt's model; today, with considerably more, much higher resolution, across many more EM wavebands observations, Peratt's model clearly fails both "shape" and "stability" criteria (an example: http://www.cv.nrao.edu/~abridle/dragnparts.htm).

Finally, we now have independent estimates of the radial distribution of mass in galaxies, from analyses of gravitational lensing, something not available to any sign

Hmmm.. maybe it got something to do with the estimated 5yr orbit of the asteroid.

One has to be sure that it is a unique one and not another one that strayed from its recorded orbit. (by collision with another asteroid)

Hmmm.. maybe it got something to do with the estimated 5yr orbit of the asteroid.

One has to be sure that it is a unique one and not another one that strayed from its recorded orbit. (by collision with another asteroid)

You can't have those particular proprietary programs. But with the exception of iTunes, you will find programs which do the same things exactly as well. The ones you are looking for are:

• Flash player and PDF reader are available direct from Adobe. Additionaly, there are several open source flassh players, and PDF renderers are everywhere. Open source Action Script compiler here. Blender can directly generate Flash movies as good as anything produced anywhere, while lots of other Linux programs can produce some Flash output;
• Open Office; KOffice;
• granted, there's no equivalent to iTunes which will talk to the iTunes store;
• Freewheeling, SooperLooper, Audacity, Rosegarden...;
• Starry nights? Hell! you know the professionals use Linux, don't you? Start here and stop somewhere beyond the horsehead nebula...
• As for GPS software, the list is so long I don't know where to start. Anything you want to do with more or less any GPS - from professional navigation for shipping (although that's proprietary and expensive) to mapping your walks in the woods - is available. What is it you want to do?

There's a growing trend in math (and maybe other disciplines, for all I know) away from non-free publishing.

Prominent mathematicians have been complaining for years (more links here) about overpriced journals, and entire editorial boards of some journals have resigned in protest (see a list of mass resignations and similar changes here). There are now plenty of entirely free journals in combinatorics, topology, and other fields, and pretty much everything that gets published these days is either available on the author's website or on the arXiv.

So modern research tends to be free, but what about all the books you need to read before you understand this research? Sure, a copy of Rudin may be expensive and there's not much we can do about that, but maybe you can learn from the free analysis course notes at MIT's OCW site. You complain that EGA is out of print, but basically everything Grothendieck wrote is available for free, and you can even get them along with tons of other old French publications through NUMDAM. (There's even a project to transcribe SGA into LaTeX.) Lots of other books are free to download legally (and this is by no means a complete list), even though many are commercially published as well.

Finally, you can complain all you want about university tuition, but I really doubt that free tuition is going to open up mathematics to the masses. Ultimately the very top students who can't afford it are getting scholarships and grants to cover their education (and I do know some people who got free rides at Princeton because they couldn't afford it -- that school is definitely more generous than most), and since most other people couldn't get into Princeton anyway the tuition is never even an issue for them. The best way to make mathematics more accessible is to give everyone access to free textbooks and current research, and the "marxist university professors" you deride have been gradually moving in that direction for years now.

By the way, what do you think has been done to damage the Princeton math department's reputation? Whatever you think Shapiro and Tilghman have done to the university, nobody in their right mind would deny that it's one of the top few in the world and I doubt most people would openly proclaim any one department to be the best anyway.

How I temporarily fixed the flickering screen of my Thinkpad.

Yes, that is indeed a pen cap you see sticking out of the laptop. It worked long enough for me to finish the paper.

The one argument I've heard against it is that it can't do animations

pdfanim lets you add animations in. The only downside is that xpdf doesn't currently support them (but it does fail gracefully). I've done several talks using this, both on my own laptop and on random machines at conferences and it always works flawlessly (wish I could say the same about my part of the presentation, but at least when you know the tech will work, you can concentrate on the more important parts).

Albert Einstein's theory of relativity, published 1905-17, challenged well-established principles and concepts of physics, yet was widely accepted by 1930, although doubts about the validity of the general theory persisted for decades.

Map your hard disk with it, just for fun. I am also exploring its utility in detecting trends within my psychological/experimental data.

hence the line about patching asap - preferably with a wire cutter, just for dramatic effect :)
seriously, these computers should never be connected to the a public network. If this must be done, possibly for remote monitoring, it could be done with hardware such as this: Network diode. It's not infallible, but it's an extra layer of security on top of firewalls and such.

Granted, I haven't read the fine print on OIT's position, but based on their ads on the busses and what's been run in the Diamondback (school paper), the University of Maryland will be doing absolutely no assistance for students whatsoever.

This is good for the institution overall because we already don't have any money left over, but OIT has been warning students for quite some time that they're not invincible or invisible, and it's only a matter of time before someone gets upset at them.

Looks like that time has come... Here, have fun with this, too - http://www.oit.umd.edu/PlayFair/index.html

Here is the complete list of canonical smilies:
http://www.astro.umd.edu/~marshall/smileys.html

Wow, bring on the xenophobes!!
</quote>

Eh? I'm not the one defaming a whole nation with some simplistic blather.You are.

<quote>

First off-I was talking about how Indians are culturally not bothered about privacy, let alone online privacy
</quote>

I fail to see why this is a bad thing. The Americans are concerned about privacy because they have the luxury to do so. We do not. There are more important things.

<quote>
no one raises a word of protest
</quote>

Er, to cite the Rushdie case as an example (as you did), if the left-wing/Communist media, intelligentsia and politicians pander to the interests of these fundamentalists as part of the insidious politics of the votebank then this wouldn't happen now would it? "Privacy rights" has nothing to do with it. It's entirely offtopic and qualifies as a rant.

<quote>
What's the use of having these rights in the constitution if no one is going to bother when they are violated??
</quote>


They DO, my dear ignoramus, or did you conveniently forget the public interest litigation filed against that bitch Indira Gandhi and her Congress (I) thugs when she tried to convert our country into a police state?

<quote>
Freedom is binary-you either have it or you don't
</quote>

Wrong again, my dear self-loather. Freedom is a complex and nuanced business, and needs to be implemented with different priorities given to it's many aspects. What are you, Ernesto Guevara? Go live in a jungle with your Naxalite friends.

<quote>
Freedom 'subject to the following terms and conditions' is an oxymoron
</quote>

Absurd. What you're implicitly referring to (absolute freedom) gives rise to absolute anarchy. "Freedom" in the sense of "Democracy" DOES mean 'subject to certain terms', like LAWS. Or would you rather our nation degenerate into riots.

Either you believe everything that NASA interprets in its images as word of God, or there is the possibility that those white-outs are electrical arcs.

We've actually witnessed collisions in space. And found evidence on earth for them. We've never seen any evidence for electrical arcs between heavenly bodies that would cause craters.

Only when an event cannot be explained by any existing model formed from previous observations, will they resort to wild guessing ( see string theory, multiple universe theory, etc).

Single Instruction, Multiple Data (SIMD) processors are also known as short vector processors. They enable a single instruction to process multiple pieces of data simultaneously. They work by allowing multiple pieces of data to be packed into one data word and enabling the instruction to act on each piece of data. This is useful in processing cases where the same operation has to performed on large amounts of data. For example, take image processing. A common operation found in programs such as Photoshop would be to reduce the amount of red in an image by half. Assuming a 32-bit traditional processor that is Single Instruction, Single Data (SISD) and a 24 bit image, the information for one pixel would be put into one 32-bit word for processing. Each pixel would have to be processed individually. In a 128-bit SIMD processor, four 32-bit pixels could be packed into one 128-bit word and all four pixels could be processed simultaneously. Theoretically, this translates to a four fold improvement in processing time.

It'd be cool if something like this was self-powered and could be controlled by EMG (the electric signals given off by contracting muscles), sort of like this prehensile tail that some folks made at the Telluride Neuromorphic Workshop a few years back:

http://www.isr.umd.edu/Labs/CSSL/horiuchilab/proje cts/EMGtail/emg_tail.html

You only need a 10km diameter ice (not even rock or iron) asteroid to wipe out humanity due to aftereffects alone, not to mention quake:

Energy Released: 10 million MT (MegaTons of TNT)
(Shoemaker Levy 9 collision with Jupiter: 5 million MT)

QUAKE!! Magnitude 10.3 (largest recorded Earthquake: 9.5)

Crater Diameter: 67.3 km
Crater Depth: 1.0 km

Ohh! Look at all the dust in Earth's atmosphere! It's going to block the sunlight and make it very very cold there for many years. There will be another wave of mass extinctions. You humans will not survive.

See http://janus.astro.umd.edu/astro/impact/

If problems with pasting, maybe a link would do. And this one seems to cover the first use of plain chars smiley, in 1982. Tho in other system there were tricks to overlay chars and create single "cell" smileys, in the 70s. I also found a huge list of smileys.

Why would you change though? Bioses are only used for booting these days

http://www.missl.cs.umd.edu/winint/index2.html

A few equipment query functions and a lot of INT 13 calls to read sectors off the disk. And INT 13 supports 64 bit LBAs which will last essentially forever - drives of upto 8 Zetabytes ( 8*(2^70) bytes ) are possible.

The original reason for EFI was because Itaniums needed a firmware standard because the Bios is x86 only. Macs use it mostly to stop people booting OSX on normal PC hardware as far as I can see.

There's a good reason for not using EFI too. EFI graphics cards need to have EFI byte code in Flash along with a normal x86 Bios unless they want to only work on EFI systems. That means more flash memory. Or the installation utility could copy the EFI driver into a FAT formatted EFI system partition, but that means if something corrupts it the card will stop working on a legacy free EFI system.

Actually, come to think of it, video bioses are a special case. On Windows XP, the driver can use Int 10 to call the video bios.

Hmm, it seems that this is disabled on Vista -

http://72.14.235.104/search?q=cache:URuKNsrXQDAJ:d ownload.microsoft.com/download/9/c/5/9c5b2167-8017 -4bae-9fde-d599bac8184a/WDDM_BIOS.doc+int+10+windo ws+vista+driver&hl=en&ct=clnk&cd=1&gl=us

So it seems like the Bios is used so little and is so futureproof that it doesn't do any harm to keep it. It's also small and simple and can run purely from Rom, whereas EFI needs a special partition which could be corrupted.

Well Seagate say a maximum drive temperature of 60C

http://www.seagate.com/support/disc/manuals/ata/10 0389997c.pdf page 12

But that might not be the whole story

From here
http://www.calce.umd.edu/whats_new/2003/1203.pdf
"Nakamura (2001) derived an activation energy of 1.27 eV for the fatigue of piggyback PZT actuators, a common wearout mechanism, which resulted in a predicted lifetime of 6.4 years when operating at 3 kHz at 25C."

Googling for the paper I can only get the abstract
http://ieeexplore.ieee.org/Xplore/login.jsp?url=/i el5/20/19818/00917646.pdf?arnumber=917646
"Summary:The experimental lifetime predictive equation for a piggyback PZT actuator was derived. A piggyback actuator is a fine actuator of a dual-stage servo system that is essential to increase the recording density of hard disk drives (HDD's). The obtained equation agrees with Arrhenius' equation."

Arrhenius's equation give a reaction rate which is exponential with temperature

http://www.sas.upenn.edu/~wwalsh/arrhenius.html

So the drive will fail faster at 60C than at 25C. You could actually work out the constants in the equation from the figures in the first link and then work out the fail time at 60C. I can convince myself to spend a few dollars on a big fan from the above graph though. This guy

http://www.silentmods.com/section2/item213/part3

says "At the temperature of 65 C the life time of hard disks is shortened two times if not more.". Looking at the Arrhenius graphs above that might well be the case.

Or if you can't fit a fan to you Mac, try to get a low power drive. Either a 5400rpm one, or even a 2.5" one and an adaptor. Since you need an adaptor anyway, you could even get a 2.5" SATA drive and a mounting kit (ideally one that acts like a big heatsink) and connect it via a PATA to SATA dongle.

Well, some of the rules in language are pretty universal. I hesitate to say hard-wired because I can't cite it, but think about it. Every language consists of syllables that add up to words that add up to a complete thought.
That's how an infant learns it. At first, they just babble as they figure out what sounds they can make - naturally, what sounds human language will have in them. Try and think of a language that doesn't have a soft A vowel as English does.

And deaf babies babble too! It is, however, less complex than a non-hearing impaired infant's. That makes for some interesting theories. If a deaf infant can figure out some consonants, something's probably hard-wired.

Pay attention to it! That babbling is nonsense, but eventually nonsense syllables.

What are some first words you can think of? nana. dada. papi. That indicates that they've gotten far enough in development to know that syllables make up words.

Now here's why I think you are right about the computer not "learning like a baby does". A baby can easily pick up what "dada" and "mama" are quick, what is mama gonna do every time the baby says it? This computer won't learn like an infant will, it will learn language as a blind infant would.

• Medterms.com"The uniform determination of death. The National Conference of Commissioners on Uniform State Laws in 1980 formulated the Uniform Determination of Death Act. It states that: "An individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem is dead. A determination of death must be made in accordance with accepted medical standards." This definition was approved by the American Medical Association in 1980 and by the American Bar Association in 1981."
• Another Link "In 1968 the Harvard Medical School Committee developed a definition of death. According to this definition, a person is brain dead when he or she has suffered irreversible cessation of the functions of the entire brain, including the brain stem. "
• Biology, Consciousness, and the Definition of Death "Two landmark reports helped to generate a movement away from exclusive reliance on the traditional standard: the 1968 report of the Harvard Medical School Ad Hoc Committee and a 1981 presidential commission report, Defining Death. This second document included what became the Uniform Determination of Death Act (UDDA). Today all fifty states and the District of Columbia follow the UDDA in recognizing whole-brain death -- irreversible cessation of all functions of the entire brain -- as a legal standard of death. The UDDA doesn't jettison the cardiopulmonary standard, however. Instead, it holds that death occurs whenever either standard (whichever applies first) is met. One important consequence of this change is that an individual can be legally dead even if her cardiopulmonary system continues to function. If a patient's entire brain is nonfunctioning, so that breathing and heartbeat are maintained only by artificial life-supports, that patient meets the whole-brain standard of death."

If you check out their papers, they really have solved the parallel programming problem. They've shown impressive speedup on such impossible-to-parallelize algorithms as Matrix Multiply and Randomized Quicksort....... oh wait, those are really easy to parallelize. Well, maybe I can still get my desktop supercomputer so long as I want to compute really, really big matrices on my desktop. Now the only trick is finding a way to encode Quake as series of giant matrix multiplies.... http://www.umiacs.umd.edu/users/vishkin/XMT/spaa07 paper.pdf Oh, and feel free to breeze over the part about no floating point support. Everyone knows that the really hard programming problems involve integer-only matrices. :-P And just to throw one more fun fact in there, this thing lives in a PCI slot (not even PCI-x), so getting data in and out of this thing is going to take an obscene amount of time. I don't want to bash it too much, but saying that this thing is a desktop supercomputer capable of a 100x performance boost is pure BS. It's yet another example of a way to decelerate single-threaded applications while leaving the hard part of parallel programming and program partitioning up in the air. PRAM isn't really an answer to that. The only reason this is getting any publicity is the $500 naming game.

The number of cores is expected to double every 18 months for the next decade and
reach 256 in a decade.

Right. Not sure I'm with you there. 256 cores is a lot, and I doubt that the infrastructure of (e.g.) memory bandwidth and power supply would be able to keep up with such demands.

Clock rates of commodity processors have stopped improving since mid-2003. This
followed several decades in which clock rates have doubled every 18 months.

Right. You know, I'm sure the fastest desktop processor you could buy in June 2003 had a clock speed of about 3GHz. Clearly I'm imagining the availability of 4GHz chips on the market today. Yeah, sure, it's slowed down. It hasn't stopped, though. I'm also clearly imagining that Core2 chips achieve more calculations per core-second than Pentium 4 chips running at significantly faster clock speeds.

Basically, the entire thesis here is that improvement in individual processor core performance has been halted for the last 4 years. This blantantly is not the case.

[Vishkin] opined that a mathematical
model, called PRAM for Parallel Random-Access Model (or Machine), would be a
proper framework. The PRAM is a simple extension to the standard RAM (for random access machine)
model used to teach serial algorithms in every standard Computer Science curriculum.

Can somebody help me out here. I've never heard of this "random access machine" model. Are we talking about a von Neumann machine, or something else?

In his PhD thesis, Vishkin proposed a simple "work-depth"
methodology for designing parallel algorithms: Formulate your algorithm in the form of
rounds, where each round can include any number of operations that could all be
performed concurrently had there been enough hardware to execute them. For
performance, the design objective should be to minimize two parameters: (i) work - the
total number of operations over all rounds, and (ii) depth - the number of rounds. A
simple example for such a parallel algorithm follows.

Well, duh. Thanks for enlightening us. To improve performance, minimize the number of steps that must be taken sequentially, and perform as many as possible in parallel, but don't make too many parallel ones either. Clearly revolutionary thinking, there.

PRAM algorithms often allow an "arbitrary concurrent write" resolution, where several
concurrent attempts to write into the same memory location result in one of these writes,
but we don't know in advance which one. Note also that such "semantics" cannot even be
expressed in any of the common serial programming languages.

...

Err, OK. Me, I thought starting several threads and making them all write to the same location would result in an unpredictable choice of the values written being stored in that location in standard languages. But then I don't have a PhD in parallel programming techniques, just ten years of industry experience writing multithreaded software, so what do I know?

All successful general-purpose computers since the 1940s rely on the so-called Von-
Neumann apparatus. Is there a way to upgrade, rather than completely replace, this
successful apparatus to handle parallelism?

Yes. You place multiple von neumann machines with access to the same memory, and provide wtructures for sending control signals between them so that a thread on one processor can start a new thread on another one. This is generally called SMP, and has been used extensively since a long time before this paper was written, so why are you even asking the question? There are of course alternative approaches (e.g. NUMA) that can provide better efficiency in some cases, but the basic question is answered already.

Its very interesting reading the paper linked to the link http://www.umiacs.umd.edu/users/vishkin/XMT/spaa07 paper.pdf. It reminds me of Mercury Computing Programming Toolkit for Cell Processor Programming. They too have a spawn and join method of concurrent programming see: http://www.mc.com/uploadedImages/MCF-FOE-model.jpg at http://www.mc.com/microsites/cell/ProductDetails.a spx?id=2824. Notice the worker/manager similarity to the spawn/join semantic. It would appear that this chip is fundamentally the same, but provides implicit engine allocation. Very interesting....

Well, you should learn to follow links.
It was quite easy from the article to find more information about the project.

Is this "MagneticRam" you're referring to a thing of a future, or of the past?

I agree about the individual bands being important.
However, a great deal of LandSat _is_ available freely through GLCF ESDI (http://glcfapp.umiacs.umd.edu:8080/esdi/index.jsp ), with all its bands, and has been for years. So while most of the posters here aren't quite informed, their basic question is relevant: Why is NASA making this new website? I can imagine a few possible reasons.
1. They want to do GLCF a favor by offloading their servers?
2. Maybe they will offer more complete set of LandSat with different timestamps?
3. Some political reason?
-Ben

Beware: if you search for ice regelation on google, some web sites propagate the error that the mechanism of ice skaing is regelation. As you can calculate in the question sheet, regelation does not give sufficient depression of the melting point over long enough for it to be important for ice skating.

It seems clear from the literature (but disappointing) that regelation is not the cause of the ice being slippery when you ice skate. A paper published in Physics Today in December 2005 and listed in the references for this demonstration, discusses the concept, initially proposed by Faraday, that a microscopic layer of water, found on ice even at very low temperatures, is responsible for ice being slippery. On the other hand, regelation apparently is a primary contributing cause for the motion of glaciers, as discussed in one of the references.

There is a lot of discussion about whether this really demonstrates regelation, but rather simply conduction of heat by the wire to the ice cube so that it will melt, followed by freezing over of the cut due to conduction of heat away from the cut to the surrounding ice.

The problem is that two researchers using the same equipment but better neutron detectors couldn't replicate the results, and these guys were from the same lab (Oak Ridge). Taleyarkhan then moves onto Purdue where the "supporting" paper comes out. The authors of that paper are Taleyarkhan's students, whom are suspected of contributing very little to the work or the paper. This is in fact the situation that you think would make a bad precedent, but it is also the reason that there was a fraud investigation (that Purdue apparently put a halt to when it appeared the investigation was going to uncover fraud).

The whole thing stinks from to to bottom because Taleyarkhan's first paper, which appeared in Science, was recommended to not be published by the to authors whom couldn't reproduce the results on the same instrument. Science ignored that, then passed the paper on to reviewers without informing them that the results couldn't be repeated. It turns out they had to pass it around to about a dozen reviewers, which is usually a bad sign because that usually means they kept hearing the thumbs-down from the reviewers. They finally decided to publish the paper under an embargo (gag order) and did so with much hoop-la and fan-fare. A better summary of events is here. Science basically dumped their scientific integrity for sensationalist headlines.

Purdue has been asked to re-open the case, but as of the writing of the article, has not (but I'm sure Purdue will).

You need to look at the history of this story. It is full of coverups, or at least the appearance of coverups. The university seems to have gone to great lengths to keep this under wraps. Bob Park has done a pretty good job covering the progress of this over the years. 1 2 3 4

Purdue has been asked to re-open the case, but as of the writing of the article, has not (but I'm sure Purdue will).

You need to look at the history of this story. It is full of coverups, or at least the appearance of coverups. The university seems to have gone to great lengths to keep this under wraps. Bob Park has done a pretty good job covering the progress of this over the years. 1 2 3 4

Purdue has been asked to re-open the case, but as of the writing of the article, has not (but I'm sure Purdue will).

You need to look at the history of this story. It is full of coverups, or at least the appearance of coverups. The university seems to have gone to great lengths to keep this under wraps. Bob Park has done a pretty good job covering the progress of this over the years. 1 2 3 4

Purdue has been asked to re-open the case, but as of the writing of the article, has not (but I'm sure Purdue will).

You need to look at the history of this story. It is full of coverups, or at least the appearance of coverups. The university seems to have gone to great lengths to keep this under wraps. Bob Park has done a pretty good job covering the progress of this over the years. 1 2 3 4

Mouse, whatever... Wake me up when computer scientists can model an insect brain!

PDF doesn't always cut it as one often uses animations.

Related see this audio maps project (via C). Fron the former link: "In the case of geo-referenced data where users need to combine demographic, economic or other data in a geographic context for decision-making, we designed iSonic, an interactive sonification tool that allows users to explore in highly coordinated table and choropleth map views of the data. Sounds of various timbres and pitches are tied to map regions and other interface widgets to create a virtual auditory data display."

The interesting feature of this announcement is how little computation and how much intelligence in software development was involved by the standards of other large computational projects. The calculation took three days on SAGE, which is an eight-socket dual-core Opteron system with 64GB of memory; it's perhaps three orders of magnitude less calculation than the factorisation of RSA200, or than IBM's work modelling hafnium silicates for developing 45nm processes. It is very much less work than is routinely done commercially for chip simulation or seismic inversion.

On the other hand, even if some of the tricks they used were fairly routine (you have a reasonable idea how large the coefficients are? The coefficients are obtained only by multiplication and addition? Why not calculate modulo lots of coprime one-byte integers and save a factor eight in storage space?) it's remarkably clever work.

http://atlas.math.umd.edu/kle8.narrative.html

and

http://atlas.math.umd.edu/kle8.html

are a description of the project aimed at reasonable mathematicians, with a lot more in them than the press release; but I think this item is mostly useful to tell mathematicians how to write a press release which gets picked up about what is fairly abstruse work by the standards of computational group theory.

The interesting feature of this announcement is how little computation and how much intelligence in software development was involved by the standards of other large computational projects. The calculation took three days on SAGE, which is an eight-socket dual-core Opteron system with 64GB of memory; it's perhaps three orders of magnitude less calculation than the factorisation of RSA200, or than IBM's work modelling hafnium silicates for developing 45nm processes. It is very much less work than is routinely done commercially for chip simulation or seismic inversion.

On the other hand, even if some of the tricks they used were fairly routine (you have a reasonable idea how large the coefficients are? The coefficients are obtained only by multiplication and addition? Why not calculate modulo lots of coprime one-byte integers and save a factor eight in storage space?) it's remarkably clever work.

http://atlas.math.umd.edu/kle8.narrative.html

and

http://atlas.math.umd.edu/kle8.html

are a description of the project aimed at reasonable mathematicians, with a lot more in them than the press release; but I think this item is mostly useful to tell mathematicians how to write a press release which gets picked up about what is fairly abstruse work by the standards of computational group theory.

There is a very similar OSS research project called Ferret by a prof at UMD. I used to be IT support for an institution he is a member of. (Institute for Systems Research)

http://www.enre.umd.edu/faculty/cukier.htm

http://ferret.sourceforge.net/

A templating language's support for math functions does not get in the way of designers using it. They don't need to know math in order to use it. Your argument that designers don't deserve to be able to use math even when they need it is ridiculous. Maybe your designers are mathematically illiterate, and your templates are extremely simple, but don't try to force your low standards on the rest of the world. There is nothing about supporting math that makes a templating language hard to use.

In fact Smarty does support some math functions, but not all of the functions supported by PHP. So are you actually arguing that Smart goes to far in its support for math?

Since when were you the final authority of which functions view logic should be allowed to call? I often need to round a number to a particular number of decimal places in the view, so why are you arguing that I shouldn't be able to?

As for your guess that I don't know MVC: I've writing user interface toolkits since 1986, when I developed pie menus for the X10 "uwm" window manager, and I've been regularly using OOP and MVC since at 1987 or so. When and how did you learn about object oriented programming and MVC? Do you know enough about MVC to offer any criticism of it, or do you just blindly accept it as a given without questioning it?

The hypermedia formatting and templating language I developed around 1987 was called the "HyperTIES Markup Language" for Sun workstation version of the HyperTIES hypermedia browser, while I was working for Ben Shneiderman at the University of Maryland Human Computer Interaction Lab. I implemented the first version in Forth, and it had full access for Forth expressions, conditionals, loops, etc. We implemented the second version in C, and it had a full set of mathematical and string processing functions, as well as the ability to define macros, conditionals, loops, etc.

Here is a description (including links to the source code) of the HyperTIES Hypermedia Browser and Emacs Authoring Tool for NeWS, and also a paper we published about HyperTIES in the ACM journal "Hypermedia" Volume 3, Issue 2 (1991): Designing to Facilitate Browsing: A Look Back at the Hyperties Workstation Browser [reference].

You should read the paper we published in 1991, because it gives a good explanation of why templating languages should support macros, math and string processing functions. One reason is conditional text. The conditions must be able to evaluate conditional expressions, which need to be able to call math and logic fuctions, as well as many other utility functions that are useful for authoring conditional text.

Have you published or can you reference any peer reviewed papers that support your point that templating languages should not support math? But it seems like you don't know templating languages, anyway.

From Designing to Facilitate Browsing: A Look Back at the Hyperties Workstation Browser:

Generating customizable documents

To achieve effective formatting we created the Hyperties Markup Language (HML) in 1988. It includes standard markup language features and conditional text to easily customize the document based on user actions. Although traditional Generalized Markup Languages, the Interleaf document preparation system, and scripting languages such as Hypertalk enable authors to specify conditional appearance of text, we feel that this feature should appear as a regular part of hypertext systems. Our empirical studies have shown that by limiting the amount of text on the

The contention that "information wants to be free" is a catchy way of saying "the properties of digital goods are such that their natural marginal cost is zero or practically indistinguishable from zero."

The contention that information wants to be free is a catchy way of ignoring that "the properties of digital goods are such that their natural startup cost is non-zero for any information which is concise, categorized, and subject to quality assurance/quality control."

You can argue about marginal costs of reproduction until the end of time, but the information that people want to acquire is scarce, costly (in the sense that finite human labor is a necessary element of its creation and rendering into a useful form), and most importantly, at least in modern economies, rivalrous. Vast stores of old information are discarded in favor of "superior" new information, at least in part because consumption of information still entails an opportunity cost to the consumer.

To those who selectively quote the marginal cost pricing aspect of economics that they learned in their survey course, I suggest that you review the vast body of literature discussing the so-called "hot news doctrine" in law and economics. You could start here.

There is a 70% drop out rate from classes designed to force that drop out rate in both those degrees. Then on the "non weed out" courses my friends over in the teaching programs were doing maybe 10 hours a week per class (at most) while those in the COSC program were doing 35 hours a week for the database class alone. It was not uncommon at all to spend 30 hours a week studying for advanced physics and math courses either.

I stand overwhelmed by the power of your anecdotal evidence. Consider, however, the possibility that the few people you happened to know at your one school may not really provide you with a very clear idea of the situation. I will say, however, that I and most of my friends probably didn't spend much in excess of 10 hours a week on our Physics classes when getting out B.S. degrees. I don't think I spent considerably more time than that on a single class until grad school.

Another point I should have made is that I don't think pay levels generally do (or necessarily should) have much correlation to the difficulty in obtaining a degree. Hell, by that measure people with business degrees shouldn't even be able to earn minimum wage (ok, now that's my prejudice). A lot of it has to do with the danger, unpleasantness, difficulty, etc. of the day to day performance of the job. As I indicated before, I think the day to day difficulty and sometimes unpleasantness of teaching K-12 can be pretty high. Of course, what's largely important is how many people can do the job, and without proper evaluation it's really hard to say who's up to the task.

I agree that money would attract quality- but how do you determine what is quality? You often do not see the real results of good teaching for over a decade. While a good teacher has an enormous impact, there is almost no way to measure that a teacher is instilling a desire to learn into students vs simply ramming material into them for the tests. It's a very difficult to find a reasonable and reliable metric for what a "good teacher" is.

It's certainly not easy to measure the effectiveness of teaching, but there certainly are metrics that will give you some idea. In Physics, there's been a lot of research into this in recent years. For example, to address your point there are attitude surveys that help to measure if a course makes students more enthused about a subject. Testing before and after teaching can tell you something about the effect of the teacher. Together with several different measures of performance on material, this can give you some idea of which teachers are doing well and which ones aren't. Now, one obviously has to first try to train teachers and get them to improve, but in principle long term substandard performance could certainly be grounds for firing and above average performance ground for raises or bonuses.

"The most typical test of hardness is attempting to scratch a material. (To measure a material's hardness on the Mohs scale, essentially a series of scratch tests are performed, and a material's place on the Mohs scale was determined by what it could scratch vs. what would scratch it.)"

In the machining world and other places, where more accuracy is needed, "hardness" is defined as "resistance to penetration" or "resistance to plastic deformation, usually by indentation" (Metals Handbook) as in a diamond or ball bearing is placed upon the material and then a force is applied. The depth into the material or width of the mark is measured and matched to a scale (Rockwell, Brinell, Vickers, Knoop etc).

More than what most people want to know about hardness:

http://www.calce.umd.edu/general/Facilities/Hardne ss_ad_.htm

Testing using Vickers, Knoop, Rockwell, and Brinell is much more accurate than the Mohs scale method, but there are file sets you can buy that will measure hardness in the same way as the Mohs scale, for portability reasons.

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=175861 9&PMT4NO=17662942

--
BMO

Windows RG Edition

Galactic dark matter has a problem called MOND. If we don't agree with MOND on the galactic scale then we need to obtain MOND from our theories of formation of dark matter, because MOND agrees very well with the observed galactic data, even predicting the very low dark matter and the very high dark matter ratios obtained for the different galaxies, which this report calls problematic.
See http://www.astro.umd.edu/~ssm/mond/ for further information on MOND.

All I can find is their list of publications and their 'Homeland Security' website. Apparently UM is very 'prepares' - or they've just made a bunch of lists with staff people's names on them.