Slashdot Mirror

Projects are not formats. Projects will win on merits (eventually). Formats can be quashed forever if a monopoly player leverages their power.

Microsoft has done this before, and is in the process of doing it again with e-ink formats. The open InkML format http://www.w3.org/TR/InkML/ and the Jot interchange format http://unipen.nici.kun.nl/jot.html format, which Microsoft even participated in developing, have been abandoned for their own closed, proprietary and patent encumbered format in Tablet PCs.

Remember, this is the binary Ink format which ODF does not support, and which Microsoft states is one of the reasons they won't support ODF. This is all about leverage. Microsoft is leveraging its desktop monopoly to quash Jot. They're leveraging their monopoly to quash InkML. They're leveraging their monopoly to try to quash ODF.

They're doing this so that their customers cannot migrate to better alternatives when they're available, and developers like myself don't even try to compete, because we know those customers we might attract are nailed to Microsoft by those proprietary formats. That's wonderful for Microsoft, but bloody awful for customers and competitors.

It's diamagnetism, not paramagnetism, but yes, the frogs are generally fine, or at least they live as long as average. (If levitated frogs all acquire borderline personality disorders, beleve in Thetans and Zemu, or gain triskaidekaphobia, how would we tell?)

http://www.hfml.sci.kun.nl/froglev.html

This system has since been open sourced under the GPL license and my new research group here at University College Dublin is working on completing, documenting, evaluating, and formally specifying the system.

I led the evaluation of this system's external network security for the Dutch government while at the SoS Group at Radbound University Nijmegen.

I was also the co-author of the vote tally application for the European Elections in Holland. That application was written in less than eight weeks using formal methods to ensure that the software of extremely high quality and indeed every vote was counted. This system was written in Java with JML annotations and was partially statically checked (verified) with ESC/Java2.

See the paper "Electronic and Internet Voting in The Netherlands for more high-level information.

No, going from sequence to structure is a big problem; see e.g. the CASP competition. The fundamental difficulty is that protein folding involves many complex interactions between amino acid side chains and solvent molecules, getting you into a world of nightmarish quantum chemistry where energy landscapes are rugged and rules are made to be broken.

In general there are two ways to approach structure prediction. The most reliable is homology modeling where you basically find a similar protein sequence (i.e. a close evolutionary relative) whose structure is known. Current protein database searches generally rely on probabilistic models borrowed from natural language processing and speech recognition, primarily hidden Markov models. Essentially, these models address the evolutionary process (which describes how different proteins are related), rather than the folding process (which describes how individual proteins fold).

If there aren't any similar proteins with known structure, you're into the domain of novel fold prediction, the second (harder) way to predict structure. The current best novel fold prediction methods begin by breaking the protein sequence into lots of tiny fragments (think words), then doing homology modeling on these fragments... e.g. the ROSETTA program from David Baker's group.

Simulating the full folding kinetics, as folding@home does, is even harder, and involves wading knee-deep into all that nightmarish quantum chemistry (or approximating it). Here you are interested in not only the final folded structure of the protein, but also its intermediate structures (hence the applicability of this approach to study of misfolding diseases, such as those involving prions).

Thank you DeepStream for pointing out the difference between folding@home and this ROSETTA-related project... teach me to respond without rtfa...

Floating Frogs

The descriptions of the tsunamis were incredible (I know it's a fiction book, but still...): 100 ft. high waves travelling at high speeds, one after another. Sure, some buildings may survive one of those, but several?

Good book, but had to give it back to the library before I could finish it.

Random points:

• I'm not sure about your spin directions - I thought that ferromagnets aligned with the field. Could be wrong though.
• Ferromagnetic materials will become paramagnetic above a certain temperature (the Curie temperature) - as the material heats up, the extra kinetic energy of the atoms causes them to wobble out of alignment, and above a certain temperature, there is no intrinsic magnetism unless an external field is applied. It's a nice example of a phase transition.
• Real levitation (including the levitating frog).
• The theorem is called "Earnshaw's Theorem", and note the word "static" - there are some stable dynamic configurations.

The Dutch Government sponsored the development of an Open Source, GPL-ed solution that is probably more appropriate and less costly in manpower than the proposed matter (not to mention the human chain of trust that has to be established). Allow me to refer you to the paper and an article in The Register, although the paper is in Dutch.

You can also have a look at the code . The Dutch text surrounding the link to the ZIP file is mainly explaining the ZIP file and showing an MD5 checksum for the archive.

In conclusion, there is verified code out there for expat/remote voting, open and accessible. I would start asking questions if anything less was used. Consider the amount of people you need to trust to make this system democratically sound, and the privacy you need to give up. Conspiracy theorists would at this point strongly suspect alterior motives, and in this case I'd actually agree with them..

eureka!
thanks sinner you gave me an idea.
maybe this sounds stupid, but wouldn't it be possible to make the base a giant sphere? essentially a hamster ball.
Two spheres really. An external sphere in contact with the moon's surface and a free-floating internal sphere - with the living quarters and such.
how to keep it floating? well, first we need a nuclear power plant (but of course). then we could find good use from our good old friend magnetism...or whatever.
then, drive it the same way a hamster drives his ball; create an magnetic impulse between the internal and external sphere. the internal sphere will try to climb the inner-wall of the external sphere and the external sphere will counter with an equal and opposite reaction which will result in forward movement. Nuclear meltdown aside, it sounds like a relatively simple concept. and it's bound to have less moving parts than some trackless-locomotive or star-wars-power-droid-lookin' hundred legged breakdown-machine.

ESC/Java has been picked up by a group based at the University of Nijmegan. Their new version, cleverly called ESC/Java2, supports the full syntax of JML for writing specifications and is more expressive than the last version from Compaq/SRC. The JML project also provides tools for runtime testing of assertions in Java code (like Java 1.4's assert, but much more expressive), and for automatically generating unit tests from method specifications.

Both the JML tools and ESC/Java2 are open source. ESC/Java2 is based on patches applied to the source available from Compaq/SRC; a combined binary download is available.

If you're interested you can get ESC/Java 2 or the JML tools by following the links.

Full disclosure (or shameless plug): The JML tools are developed primarily by my adviser's research group at Iowa State University. The tools run on top of the MultiJava compiler that I developed as part of my M.S. degree. JML works with pure Java, but you might be interested in the MultiJava language, which adds multiple dispatch and open classes to Java. More info. on Multijava is available from MultiJava.org.

The original painting, and a bit of information on the phrase "et in arcadia ego" can be found here (bigger version of the painting here. Note that you can't really make out the letters in either)

I first heard the phrase while studying Tom Stoppard's Arcadia in school, and our interpretation was close to one of the two on wikipedia:

"I, Death, am also in Arcadia"

This is a memento mori, a reminder that death is certain even if life seems perfect at the moment.

The painting features 4 shepherds in "Arcadia" (a pastoral paradise), puzzling over those words engraved in a small monument.

The artist of the Shugborough version may very well have intended for us to puzzle over his version like the shepherds in the original... and if the act of us puzzling over the carving was the artist's goal, there may well be no solution like there would be in normal puzzles. (Or there might only an arbitrary solution that cannot be attained without further data.)

Perhaps some poets should look at it in addition to code breakers.

Dunno if the energy would be there, but a strong enough magnetic field can affect just about anything.

Meanwhile, the Netherlands has had electronic voting for over 10 years now
Details here

Hell, pretty much anything becomes paramagnetic if you have strong enough fields. Some things have stronger diamagnetic properties than others though.
Aluminum is actually fairly paramagnetic, if I recall.

Back in 1997 a group even levitated a frog in a 16 Tesla field. How fun is that?

Dude,
Here is a picture of a frog levitating in a 16 Tesla (160,000 Gauss) magnet. According to this page, humans have a similar diamagnetic susceptibility to frogs.
Thus, if you could apply 16 Tesla or more over the volume of a human, he/she will levitate.

Cheers,
Johann

See, whereas I must be a different breed of /. geek.

I immediately thought of this from a much older /. article.

If the professor were in a very large levitation tube, the magnetic force would be acting on every part of his body uniformly. It's a real gravity-magnetism balanced environment, as you can see here, where the water forms a spherical bubble from water tension.

I saw something very close to that, about 2 years ago, in a newsletter from the Iowa State University physics department; they had one of the profs sitting on a disc of superconducting material that was levitating above a superconducting magnet. Imagine a larger version of the first photo on the linked page.

Sadly, I never noticed any biological effects, but then we did not climb into the center of the solenoid when it was operating.

What I would like to see is a magnet big enough and strong enough to levitate a person. I'm sure you've seen the levitating frog trick. Now if they could only scale that up because it would be a cool tourist attraction.

frog movies

Now, I may be just stupid, but I'd say the people at the
High Field Magnet Laboratory in Nijmegen have a much stronger claim
to world records... (33T continuous, 60T pulsed).

Where is the world record?

If I See Another Hyperlink I Might Explode

Is this any different from what these guys did? Actually, this link seemed fake to me when I first saw it on slashdot. They claim to use DIAMAGNETIC LEVITATION, not anti-gravity. I'm still waiting for the home model.

Levitation lives!

And yes, this one does work in a vacuum.

One of those assistants told me he's never seen such an enormous amount of public attention for a proposal in the two years that he has worked at the European parliament. He thinks there's actually a very good chance of preventing this proposal from getting approved. Really, it's easy to say "all politicians are alike" and "corporations own the politicians anyway" etc, but that's simply not true (note: I'm not a member of any political party nor politically active, except in cases like this). Yes Virginia, there still are a lot of people with a conscience in politics who want to do the best for society at large, they just need access to the right information. In cases like this, people like us can make the difference.

If a non-programmer or non-ip-lawyer reads a proposal like McCarthy's, I can perfectly imagine that it's not that difficult for that person to be convinced that she's indeed trying to protect the software development community at large. The background text of her proposal is really full of misleading and sometimes outright wrong statements to justify her goals.

For example, she cites one study which shows that software patents are beneficial to small and medium-sized companies. In the same footnote, she states that they also looked at several other studies, however, at least one of those concludes exactly the opposite. Nevertheless, the way it is put forth in her text, it seems as if all those studies show exactly the same results. There really are a lot of things like that...

You are using the term "abstract data type" in a dynamic language, and this doesn't make very much sense. The original idea of a user-defined abstract data type is that one can define a new type that works just like the built-in types "integer", "char" in Pascal. The idea is that the type is abstract in that the implementation is hidden.

Now I agree that your idea of "secure abstract data type" is in effect very similar to the traditional ADT in, for example, CLU. But it bothers me that the "type", which is a key part of the "abstract data type" concept is not explicit. You are not using "type abstraction" to enforce representation hiding. The commonly-accepted analysis of this form of abstraction is with existential types (see ADT1 or ADT2 for example)

Instead, you have created a form of "abstract data value" that can only be operated upon via the associated operations.

Basically I think that you should replace the word "abstract data type" with the word "data abstraction" everywhere. Then things would make much more sense. What you are talking about is various forms of data abstraction. Abstract data types are one very specific kind of data abstraction.

p 470-481

I actually like the basic idea behind this discussion. I hadn't read it when I started critiquing the OOP chapter. However, there are some issues hidden here that are important.

Most of the content in this section should be in the object-oriented chapter if you ask me. Your development of "bundled" data abstractions is basically an explication of objects.

I think the most important one is hinted at in your comment on page 474: "This version is secure, declarative, and bundled. Note that it does not use wrapping, since wrapping is only needed for unbundled ADTs."

This is one of the key difference between objects and ADTs: objects don't need type abstraction or any kind of explicit data hiding. Instead, objects use procedural abstraction alone. This calls into question the orthogonality of your attributes: In particular, bundled+open doesn't make sense.

To me, the difference between unbundled and bundled is the difference between ADTs and Objects. Either ADTs or Objects can be declarative or state-based. The open/secure distinction is not interesting because objects are always secure, and ADTs are only really useful if they are secure.

As a result, I would say that Figure 6.2 incorrectly classifies {Secure, Stateful, Unbundled} as a "unbundled variant of the object-oriented style". Instead, it is simply the normal stateful ADT.

The section "comparing two popular versions" should be better.

• I don't agree that "The implementations of both versions have to do actions when entering and exiting an operation. The calls of Unwrap and Wrap correspond to calls of @ and :=, respectively."
• The interface for the stateful bundled version is not clear. You should not list Push Pop and Empty as operations, since they are methods. The type should be
• fun {NewStack}: < op(push:proc {$ T}, pop:fun {$}: T, isEmpty:fun {$}: Bool)>

This is the clearest illustration that this object version is not an ADT. The type of the return value is completely visible; it is not an abstract type <Stack T>. Note that declarative bundled versions require recursive types.

It is very telling that you completely miss a very important difference between the two versions: this is that anybody can create their own implementation of stack in the object paradigm, and all these dif

Many people have already pointed out that black holes are not going to destroy the earth, but I guess people might be interested in this, which is a simulation of what a black hole event might look like. It shows an end-on view of the the ATLAS detector (picture), with most of the noise and rubbish taken out.

The curved, coloured lines are tracks left by charged particles. The green ring is the electromagnetic calorimeter, whilst the red ring is the hadronic calorimeter. Calorimeters just measure energy - so the histograms radiating out show how much energy was deposited at each point. So by looking at the histograms you can get an idea of how energetic the track was. Hope that makes sense!

Incidentally, the picture is zoomed to show the interesting detail better. The detector is extremely large! Look here for a picture that shows people standing next to it ... it's about 5 storeys high, and is in a cavern 100m underground which is about 13 storeys high. Oh, and I work on it...

I do not know what the language of the year 2000 will look like, but it will be called FORTRAN. -Attributed to many people including Seymour Cray, John Backus

BRING BACK HARMONY

Do you mean QHarmony?

You're talking about dimagnetic levitation.

This group has the flying frogs, strawberries, grasshopper and water:
HFML at University of Nijmegen

The site has movies and pictures.

We could try doing artificial gravity with diamagnetism if the Levitating frog experiment can be scaled up to work for Humans.

This same mechanism could also do star-trek style inertial damping...

The story you are referring to is this one. And an 16 gauss field can make a frog levitate! See here Magnets are really the next frontier of technology, we just spend too much money using them to throw particles around rather than using the actual natural properties of them. --ngoy

Clearly the cost of producing a ceramic hip in space would be prohibitive (ballpark: ~$1 million). Then what technology could possibly produce such a micro-gravity environment at sufficient scale on earth to effect manufacture cost-effectively? I suspect it's not as easy as floating a frog.

But that's still not as cool as when scientists levitated frogs with magnets. Since virtually all organisms have small traces of iron in them...all that's needed is an extremely powerful magnet to levitate 'em.

Heh, it makes me wonder if this magnet is strong enough not to just rip metal objects out of your pockets, but to *attract you* into it. =)

--- "A black hole is just God dividing by zero."

> ... the indigenous population of the Canary Islands. They lived on the string of islands, but never built boats and thus never actually met. They communicated between islands using whistles. In fact, their entire language was built on whistles. They are the only group of humans known to have a language built on whistles. Unfortunately, upon colonization of the Canaries, the Spanish all but wiped them out.

Close, but you got the details all wrong.
"Silbo Gomero", the whistling language of the Canary Islands is a whistled encoding of SPANISH. It would be hard for them to never have left their island and never have met strangers yet still speak a variation of Spanish. It would also be incorrect to say the Spanish colonized and wiped them out... they ARE Spanish.

You are also incorrect on two other points:
The language is spoken (whistled?) on only one of the Canary Islands, so it could not have created it in order to "communicate between islands". Instead it is theorized that it was created to facilitate communicating across the rugged and difficult to navigate terrain of the mountainous interior.
They are also NOT the only group of humans known to communicate using a whistled language. There are many examples in South America and some other locations.

The levitating frog... Here you go:


http://www-hfml.sci.kun.nl/levitate.html

Oh, ofcourse, the sed Turing Machine is on the web as well. :)

Owh, by the way, it's pretty readable sed code... it's had to be for me to finish it. :)

Arthur

The European Society for the Cognitive Sciences of Music introduces the topic of musical machine cognition.

The Music, Mind, Machine project in The Netherlands carries it further.

The Research Project on Cognitive Musicology in Finland is the last word. Enjoy!

Large in this case usually means infinite:) It's all about how the function t(n) behaves where t is the time necessary to compute the value of a certain function f(n) relative to n; it's not about comparing 2^128 to 128^1000 but about comparing 2x to x^2 and 2^x to log(x). Read Herbert S. Wilf's Algorithms and Complexity if you want to know more about it. It's the book we use in school (and it's downloadable for free).

This site has some good "Joe Sixpack" antigravity (specifically, a live frog being levitated inside a solenoid). Nothing to do with neutrinos, though.

Students in their first year CS take part in the programming team, in their second year do a bit of project management, etc. And, BTW, these are full, real-life projects that have to be delivered and meet a deadline. No simulations what so ever.

Even in Holland I believe, this is a rather unique concept that seems to work quite well (although I've never done the course myself; I didn't do CS).

I can't find links for all the parts of the course but a description can be found here (Dutch, Babelfish probably needed; look for a link "colleges", upperleft grey box, then in the small print column on the left look for GIP4)

The American college changed drastically after WWII, when it was flooded by men taking advantage of the G.I. Bill. These men were different from the prior students in that they were older,
and that they did not come from an upper class background. They knew that this was a special opportunity, and they were intent on taking advantage of it. The idea of college was emphatically not to "expand your horizons" for these men.

From the beginning of the 20th century until this time, college was primarily a place for rich young men to play football and join fraternities until they were old enough to take the position their fathers had set up for them. There was no pretense of well-roundedness from either the faculty or students in this environment either, although many of the faculty didn't really care for their students, except for the rare few who were "grinds", that went to class and actually studied.

Before this, college was more about learning Latin and Greek than anything else, on the theory that learning hard languages improved memory. :)

I'm not 100% sure, but I think the origin of the "well-rounded" student was probably from the 1960's or 1970's. In any event, I'm pretty sure the 1950's image you present is wrong. If you're interested you may want to try this link.

How does this differ from those paramagnetic fields, which can levitate frogs?

All objects (not just ferrous) are slightly magnetic. This article about flying frogs explains it well.

direct link to the .mpg of the levitating frog.

If you like Haskell, but want a mission critical ready implementation you will have to try a slightly different functional language called Clean, which has everything Haskell has as far as purity, expressiveness, elegance, rock-solid static type checking (most important feature IMO), lazy evaluation, and Clean has more like Linear (Uniqueness) Types ala Girard's Linear Logic, which allow you to have greater control over system resources, yet still maintaining functional purity and expressiveness.

GUI Spreasheet programs have been written in Clean. Video Games have been written in Clean, and even Clean's GUI integrated development environment and compiler are written in clean. There is only one problem with Clean... it is proprietary, but don't let that detract you for playing around with it for non-profit use.

Check out Clean here. You only have to pay money for the compiler if you want to use it for commercial purposes. I started out learning Functional Programming with Haskell, which is a favorite language of mine, but I ended up seeing the brilliance of Clean as a language that has the beauty of Haskell yet can still "get things done".

If you are referring to some asymptotic time complexity disadvantage of purely functional languages compared to Von Neumann languages ... well, while it might seem like such a thing is true, I have yet to see a proof. And you can use arrays through monads, in Haskell.

Also, you should check out a book titled: "The Optimal Implementation of Functional Programming Languages", which describes a new FP interpretation algorithm that is exponentially faster than the strict LISP interpreters/compilers because it optimally reduces beta-redexes (doesn't duplicate work when it doesn't have to). The nature of strict interpretation/reduction, which LISP uses, implies that function arguements are evaluated in a non-optimal way (arguements that aren't even needed are still evaluated and this can have exponential performance penalties... hell, it can have as bad of a performance hit as you want, depending on your program). While I don't know of any Haskell interpreter or compiler that uses this new theory... its just a matter of time before someone implements it.

The fact that LISP dialects don't use a strongly normalizing reduction is enough to point out several other resulting problems of the language, with regards to functional programming and programming in general.

Now, if you want the fastest full-fledged FP language available, you will want to check out Clean, which uses similar theory as the "Optimal" book mentioned above, except it uses Linear Logic theory to allow for linear types or unique types, which let the programmer destructivly update stuff, all the while keeping the language a purely functional language. Offices apps (spreadsheets and the like), video games, compilers, integrated development environments, and more have been implemented in Clean. Purity doesn't mean lack of efficiency or more difficult programming. In fact, purity means nothing more than easier program analysis... you end up with more correct programs because of it.

Clean is like Haskell with uniqueness/linear types. The only reason that I didn't make a post titled: "Why Lisp when Clean?", is because Clean is a proprietary programming language, and it is my belief that an open language has an advantage by default, over any closed language. Not that the people who maked Clean aren't cool and open, but the language is propreitary... anyway, I am ranting. Sorry bout that. It just starts happening.

I think the NASA project is basically make-work. After all, after all of the users have added their time and energy, the results are thrown away. They're not used to teach computers to recognize craters in the next evolution.

Or you could be stuck in a canister and taught how to fly!

The Divine Creatrix in a Mortal Shell that stays Crunchy in Milk

It's real alright, the physics they describe are legit. And no, you fucking morons who don't even bother to read the site, it's not done with pressurized air. They use a rather strong electromagnet (6 Megawatts), which you couldn't plug into a household outlet. Read here.

First, I think you meant a site about levitation at Nijmegen-Amsterdams University's magnet laboratory. This site has both physics and pictures :)

Second, a Levitron, which you can buy for a couple of bucks. The working principle is rather complicated, though.

Third, Nd-Be-F supermagnets should be rather cheap nowadays, so buy and try yourself :)

Andrei