Domain: tu-darmstadt.de
Stories and comments across the archive that link to tu-darmstadt.de.
Comments · 32
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Re:Solution
Has it actually been proven that it is mathematically impossible for a quantum algorithm to exist capable of defeating this system? I'm sure you could prove that any particular known algorithm wouldn't work, but the only system resistant to unknown algorithms that I'm aware of is the one-time pad.
If this has been proven I'm genuinely interested. I will confess I'm not a cryptographer.
I don't know about ring-learning-with-errors, but if it indeed reduces to an integer lattice problem, I suspect it would eventually prove to be vulnerable to some sort of attack that could be executed by a quantum computer.
As a silly example, here's a proposed attack on lattices that employs a quantum computer implementing a partial Grover's algorithm to speed up looking for solutions...
http://www.cdc.informatik.tu-darmstadt.de/reports/TR/TI-03-03.QSamplingPaper.pdf
As with many things, I doubt there is a negative proof. There's much about quantum computability that we do not understand yet (of course there is much about regular computability that we don't understand either, starting with P ?= NP). When people usually say it's resistant to quantum computers, they actually are implying that it's resistant to a quantum computer employing Shor's algorithm (and similar quantum fourier transform techiques) to factor large numbers and compute discrete logarithms (the basis behind the RSA and DH public key cryptosystems). There are other algorithms that quantum computer can run, most of which people have not even discovered yet.
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Too Narrow
I would argue that placing emphasis only on the Turing test itself is a distraction from the broad field of AI. For example, there is a ton of really cool work coming from various labs ( http://www.ias.informatik.tu-darmstadt.de/ , http://www.cs.berkeley.edu/~pabbeel/video_highlights.html).
There are many achievements met and progress made, e.g. Peters group's ping pong robot, just not the ones researchers promised many years ago. -
Prior Art: Dirk Gently's Holistic Detective AgencyWouldn't the book "Dirk Gently's Holistic Detective Agency" by Douglas Adams be prior art?
See Music and Fractal Landscapes (pdf).
It describes generating music from every aspect of nature.
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Nanotech science
From my collection:
* Nanotechnology information [archived] [2002]
* Bibliography of nanotechnology and nanoscience [pdf] [2004]
* Brad Hein's nanotechnology website
* Ned Seeman's DNA nanotech bibliography
* MEMS/nanotech reading list
* Even more publications in nanotechnology
* sci.nano archives
* The open micro/nano-manufacturing project
* Nanotech in scifi
And if anybody has links on nanomechanical synthesis, that'd be much appreciated. IIRC, nanolithography is one of the main areas of development, along with nonlinear optics to get the required precision manufacturing. -
Re: Short answer: Yes.
From what I understand, one of the only effective ways of limiting a 3rd party's access to a common AP without any administration rights would be to use spoofed 802.11 packets with the offender's MAC Address to send disassociation packets that will reset their connection, possibly causing them to have to manually cause a reconnect, and definitely causing all of their connections to dump and go through the process of reassociation and getting a new IP even if their client will automatically reconnect.
http://homepages.tu-darmstadt.de/~p_larbig/wlan/
The above includes a number of programs related to or using aircrack-ng, one of which does this kind of disassociation and other nasty things. Due to driver issues I believe this kind of thing is only possibly in linux (*nix?) right now, and even then only with certain chipsets - the same ones that allow aircrack-ng's arpreplay attack. Out of the box the code will need to be changed to target only specific high usage MAC's - or there is code in the aircrack-ng base that does a disassociation as a "one off"
http://tinyshell.be/aircrackng/forum/index.php?PHP SESSID=62e86b03ba6476a407065a1ffec82800&topic=172. 0
That is a thread on the aircrack forum discussing the tool on an older state to give you an idea of what it does out of the box. Note that running something like this is wholly anti-social, I trust you'll modify it appropriately and consider your actions carefully. I've never actually run this code base but I have every expectation that it would work as advertised - I have definitely disassociated 3rd party MAC's on wlans before and it does have the intended effect.
Discussions about shaping, QOS and traffic control are obviously the appropraite play for administrators, but I think your question was what to do as a user without any other access. This is completely unsuited for a provider. But since you asked about TCP resets - this will be dramatically more effective with no impact on the other users when modified to run in a single MAC targetted mode. Whether it's right to do it, well, you're a left to your own decision. I just thought you might appreciate a substantive reply instead of hand-wringing. -
Webbrowsers affected too
Some common webbrowsers are affected by this attack too. For example, this worked against mozilla firefox and opera in their default configuration. Using this attack, you could do a man in the middle attack against every ssl-connection. Using this attack for digital signatures on emails would have been possible too.
There are some details about the affected browsers:
http://www.cdc.informatik.tu-darmstadt.de/securebr owser/ -
Free music notation software
For simple songs and melodies there are various utilities that use abc music notation.
Here is a page listing them: http://staffweb.cms.gre.ac.uk/~c.walshaw/abc/
This lets you enter music using letters and other utilities will convert it into midi or wav files.
Something similiar and free is the Guido system. It is designed to handle more complicated pieces:
http://www.informatik.tu-darmstadt.de/AFS/GUIDO/
Another free system is Rosegarden:http://www.rosegardenmusic.com/ -
Re:We're doing it
Look here http://www.nu.tu-darmstadt.de/TVremote Ok, it is in German, but the University of Darmstadt has developed something like this 3 years ago (Wi-Fi, Java on PDA, even on a phone). Nice feature: The lesson was filmed and students could watch the recording later via Internet and thereby select "bookmarks" in the stream which they had marked during the lesson.
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Re:How about Keynote?
There is a nice package ppower4 which gives presentation effects to LaTeX, generating PDFs that work well for presentations. Many audience members will not even realize that it's not Powerpoint, which is either an endorsement of ppower4, an indictment of ppower4, or a statement about the preponderance of clueless people, depending upon your agenda. PDF viewers of all sorts have "full screen mode" and aside from needing to set the pagesize to something that works well with that, it is very effective. I usually use ppower4 to make computer projector presentations, and can just save the PDF to a USB keychain drive for the odd circumstance when the host university's projectors have difficulty with my laptop.
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Re:PDF Reader features
For a format thats so highly tied to the printed page, I'm not sure what the fuss is about online readers for PDF's.
I care because I use PPower4 for my presentations, so I need a really good online reader. Given the amount of equations and such and the fact that I'm doing LaTeX all the time for my papers anyway, PPower4 is a perfect fit for my presentation needs.
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Re:Darmstadtium? Ewwww
Darm, if I'm not mistaken, means 'intestine'. Stadt means city. So this element is Intestine-city-um.
Exactly. AFAIK the city is named after the wriggly litte rivulet Darmbach which is not quite visible any more in the city.
Darmstadt, by the way, is about the geekiest place in old Europe. Seemingly ordinary people may actually understand the print on your T-shirt there. Besides GSI, Darmstadt has a Technical University and a University of Applied Sciences. The European Space Operations Center is located there and the Fraunhofer institutes for Secure Telecooperation, Integrated Publication and Information Systems, Computer Graphics, and Structural Durability. Deutsche Telekom is running a research center there and the headquarters of T-Online are about to move to Darmstadt from the nearby town of Weiterstadt. There is a Linux User Group too. Darmstadt officially carries the title Wissenschaftsstadt (city of science). It is located about 30km south of Frankfurt/Main. The bus ride from Frankfurt airport takes 25 minutes.
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Re:Beware the license
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Re:Ten-Tec's RX-320D is a DRM-enabled receiver
"however, you will need to purchase a binary-only, proprietary decoder in order to receive DRM... this is an insidious enticement..."
You don't need to, there are alternatives - Open-Source Software Implementation of a DRM-Receiver -
Re:Software defined radio!
Already done, but not with GNURadio. There's a GNU DRM implementation already available
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Re:Neat... any open source implementations?
You may check the following links:
Software impementation under GPL
Receiver modifications to receive DRM broadcasts
Hope this helps a little -
Re:You will need special gear
Yes, but not too special. A slightly modified Shortwave Receiver and your computer running this software: ww.tu-darmstadt.de It's even available for Linux!
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Its not the first...
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Static typing.Well, someone mentioned ML earlier, but to summarize: Proving your programs correct-- or at least "mostly" correct (it's hard to prove that you have applied a function of type 'int -> int' exactly the right amount of times if you can't specify what that is) has helped a lot. Anyone who has used ML or Haskell for anything serious will probably be able to attest to how hard it is to have bugs in these, when compared to weakly typed or dynamically typed languages like C, C++, Perl, Python, Java. Haskell even typechecks for side effects (and has second-order types, or "type classes", which SML/NJ is lacking), which helps even more.
The advantage of type systems is that it is, in general, easy for programmers to figure out what kinds of things they expect ("This will be a name/int tuple... the next is either a function from int to int to int or nothing..."), and reasonably easy for compilers to infer the rest (so you can annotate your code and the compiler figures out where you're wrong-- and if you don't annotate, it'll still be able to figure out that you're wrong, just not quite as precisely where). I've now arrived at the conclusion that a programming language is worth using (as opposed to investigating) if and only if it does static type checking (with parametric types); that's just my opinion, of course.
Other advances have been in garbage collection (not having to worry about freeing your memory, manually keeping refcounts etc. is a major time-saver, prevents memory leaks, and keeps your code cleaner and more readable) and formal software engineering (e.g. done in VeriFun,
this allows you to formally verify that, given the semantics of your program, a certain statement holds-- while Hoare triples (as used e.g. in Eiffel) are somewhat useful, they're not quite as powerful as this.
So, if you want to write good software:
- Use statically typed systems
- Use garbage collection
- Formally prove your programs correct
You can, of course, do the latter by hand if you don't have verification tools (or don't have them for your language of choice). The big problem with these things is that, while they tend to lead to excellent, readable and reusable code, they're harder to do than quick perl hacks which work 99% of the time and can be done by J. Random Hacker; also, you won't find many good ML or Haskell programmers-- mostly for reasons of legacy and popularism, I guess.
For reference, I rarely do the three things above. Formal correctness proofs are non-trivial, and the problem with statically typed languages is that it's (a) hard to find good libraries for them, because (b) very few other people use them (usual chicken-and-egg problem, I guess) and (c) most of my own legacy code is in those weakly typed languages, so I'd have to re-implement big chunks of code. If we're lucky, we'll one day see C and C++ and Java and Python and Perl die out, and everyone will start using statically typed languages, formally have their programs verified etc. If it happens, it'll be years away, but I believe that it's worth working towards this goal. - Use statically typed systems
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Re:Bayesian? Wow!!! I'm sooo excited. (Irony!)First of all, it's not von Bayes. The guy was named Thomas Bayes.
Secondly, just because something is not state of the art does not mean it should be dismissed out of hand. You are right about Bayes classifiers making false assumptions about the independence of features but it has been suprisingly successful in practice, even when these assumptions have been violated. This paper shows that "...the accuracy of naive Bayes is not directly correlated with the degree of feature dependencies".
While kernel machines tend to be much more accurate (and quite cool theoretically), they are nowhere near as efficient (time and space-wise) to train. You want an intelligent spam filter to go easy on available resources and for this reason I don't think KMs are the way to go.
Another nice technology for text classification is Latent Semantic Analysis but once again, probably not the best tool for this particular job.
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Get the old one here
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TU Darmstadt
The Technical University of Darmstadt had quite a few dual-boot Linux/Windows machines in public labs. This was 3 years ago so I don't know if this is still the case.
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Re:PerspectiveBah! You want a speed comparison? Do you want a speed comparison??!!
Ladies, gentlemen and coders: I give you the Commodore 1541 snaildrive. A joyous piece of design. So elegant, so slim, so quiet, so fast...
Err...well, not quite. This brick of a drive was quite capable of generating localised black holes due to its incredibly weight. Add in the UK power supply, and you could get rid of your house's central heating system.
The speed was so thunderously slow that it was frequently beaten by tape turbo loaders. Yes. Tape beating disk.
You youngsters today, with your ATA this and your UDMA that. You don't know you're born. Why, when I were a lad we had to look on the 1541 as a luxury. Sheer IO heaven.
Bah.
Cheers,
Ian -
Now this is great news :)for the Darmstadt Dribbling Dackels !!!, winners of the Robocup german Open
What else would you expect Germans to teach little Aibo dogs? - Soccer of course!
The World Championship this year is to be in Fukuoka Japan.
Have fun!
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Re:8-bit computing
It did happen for the C64.
It was both expensive and very rare, though. A few other companies made similiar harddisks which did not catch on either.
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DRM Digital Shortwave
Some guys in Germany are working on a software decoder for DRM, this is basically a new digital radio service for SW/LW/MW radio, there's a few test transmitters running in Europe. The transmissions consist of a COFDM modulated channel and a 20-30kbps AAC stream within, doesn't sound like much but when you can get flawless delivery from Finland to Portugal and farther afield it's not bad and makes old SW look very poor indeed.
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Re:XML and Lisp.
You are right that languages from the Lisp family are a good tool to manipulate XML data streams.
But you are wrong when you tell that simple s-expressions are a good way to represent XML data streams in Lisp, due to their untyped nature.
- Simple s-expressions make it hard to cleanly separate elements, attributes, and PCDATA.
- One cannot dispatch methods over parts of simple s-expression, therefore code reusibility is lower.
Take a look at STIL (SGML Transformations In Lisp) (this is a link to a PS document). There you'll find an early experiment in the usage of Lisp for this problem class, an experiment that has influenced other style sheet language creators later on.
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I'm confused...
At first in the writeup it looked as though you were planning on compliling an image, and I thought to my self "Holy crap, self! Can complilers these days make graphics from source code?" Then I realized that you were just compiling the program to make the image. Then I looked at the example, and it looks as though you are (effectively) compiling a graphic. I'm so confused...
:o) -
Re:Shrill tonesAt least not in many countries.
The only countries that used these back when I made my recordings of such messages all over the world (heck, it was free
:-), only the US and Germany used them. OK, it's been a while since I recorded them.
Unluckily most "international" error messages today are from your local phone company :-(
ALeX -
Re:you could do it in latex.
Thanks for the link on Prosper - I may give it a try. Have you tried PPower4? Its a java postprocesor for use with LaTeX that makes snappy pdf presentations.
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I hope we shall crush in its birth the aristocracy of our monied corporations ... -
clients/codecsYou need a standard codec. You probably also want to not use the Real server.
If it is a live event, just multicast it with vic and vat.
Encode your video in MPEG-1, otherwise. You can stream this with Real (with a plugin), QuickTime, JMF (from Sun), and other things, such as the KOM player. You can also make the file available for download for those with slower connections.
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Re:Portable C64
if you want to get stuff from c64 disks (1541 & 1571), take a look her e
you'll also need a copy of star commander or trans64 (can't find a link for trans64, sorry).
it does require that you have a 1541 or 1571 drive, and i don't know about it working on the mac... but it works just great on a pc.
i seem to recall a linux driver for this style of 1541 interface a few years back, but i can't find anything about it now. it would probably work under dosemu or vmware though.
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Why old games are better
In the old days it was just not possible to create something that even remotely looked or felt like reality. Gaming developers were forced to be creative. Also I think that the gaming industry has become way too fascinated with 3d. Monitor and mouse really are somewhat more appropriate for 2d manipulation (I'm still waiting for cheap VR-glasses).
BTW: I've just implemented a nice clone of the classic 'Artillery Duel'. But I'm not sure whether the server can take much load.