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This was my first exposure to a steganopraphy demo....Written by the author of a bunch of books on Computer Networks and Operating Systems... http://www.cs.vu.nl/~ast/books/mos2/zebras.html

And he moved on from Minix, which is really a pedagogical OS, to produce Amoeba, which is and was pretty cool. And is greatly overlooked by many people.

Names of minerals are a tricky subject, and there are a lot of fallacies- a mineral may have a chemical composition, a common use name, and belong to a general group of closely-related compounds. Because of this, the guidelines do exist. It's not unlike trying to name a species of organisms.A history of the Commission on New Minerals and Mineral Names (CNMMN) demonstrates that this is not a subject touched upon lightly in the scientific world. (this comment is going to have a lot of links, because i'm interested in rocks and minerals. The info may be interesting or, as with the IMA info, useful and particularly relevant, so please bear with me.)

It becomes an issue in the everyday world more than one might expect. For example, i have anAlexandrite ring, a family heirloom. It's gorgeous, it's stunning, and it's a rock rarely seen in the jeweller's.

What's the difference between this and any other cut and polished 'ballistic missile from god'? (thank you, Mr. Watterson, for that beautiful quote.) It's pretty. So people remember it, although most people get it confused with iolite.

Amethyst is just another kind of quartz.

Rocks for which there is no scientific use frequently end up as jewellery, or even bookends, and i guess that's where a lot of the names get dropped. Rhodochrosite becomes 'that pink stone there,' and Calcite becomes (and i do not jest) "Fiberoptic stone," or sometimes "TV stone," or i've even seen it just listed as 'refractive' or 'optical' quartz. (Yeah, i've gotten kicked out of the museum of science gift shop over this one, but they let me back in when i promised to shut up.)

Personally, i think that such uses should involve the chemical composition in the labelling, sonce then people would grow up knowing the difference between nephrite and jadeite, and things labelled 'serpentine' (yes, it also talks about chromium)(see also here)and 'amazonite' would then end up consistently identified. Red ruby would be "ruby- Al2O3" and people would learn to recognise it the way they did the contents of ordinary table salt.

*sigh*

Yeah, i know nobody's going to label Paramelaconite (a tetragonal oxide of copper) for the common consumer... but isn't it a nice thought? For more on the naming of minerals, try and here, and also here, with the International Mineralogical Association.

In terms of pure science and academa, a few have been reasonably covered here already. A few from my personal library:

Anything from Donald Knuth

Andrew Tannenbaum and most of his publications

The greatest fundamental contributor to all great science, however, is inspiration. WRT/scientific inspiration, a few loom large in my mind...

Most things from:Marvin Minsky (Negative Expertise was at one point groundbreaking for me)

Richard Feynman holds a place in my personal history

Douglas R. Hofstadter and his writting, Godel, Escher, Bach

Roger Penrose and his writting, The Emperors New Mind

Carl Sagan, especially his work in The Demon-Haunted World. I read this in more recent years, and found myself launched into a new understanding and exploration of the nature of science and humanity.

...and pick any of the large number of scifi authors, of course.

UA

Nine Men's Morris has been solved by Ralph Gasser in 1996 (Draw).

So has Qubic (4x4x4 Tic-Tac-Toe) by Patashnik O in 1980. (First Player Win)

Connect Four by James Allen in September 1998. (First Player Win)

Let's see John W. Romein and Henri E. Bal from that wonderful games research group in U of Alberta solved Awari in 2002. (Draw)

Read Victor Allis' PhD thesis for a good overview on finding game theoretic results of games. He invented the proof-number search technique that he used to (re)solve Qubic and Connect-Four. http://www.cs.vu.nl/~victor/thesis.html


Nine Men's Morris is not researched actively anymore, but Ralph Gasser's paper is often cited in any paper that deals with artificial intelligence in games.

Of course, even though the game might already be solved, that does not mean that it is not fun to play...

Us Real "Old timers" used FreeBSD - which existed before the Linux kernel was a wet fart that Linus let go.

And Minix before that.

I'll have to get going faster at turning all those spare machines here into an Amoeba cluster, like I was going to eventually anyway. It's all one big machine, in that case, even if the parts are tied together with ethernet cables...

His homepage is here),
Although I could not find it on his homepage, as far as I know, the quote goes:
"The nice thing about standards is that you have so many to choose from; furthermore, if you do not like any of them, you can just wait for next year's model."
Apparently it is from his book, Computer Networks.

... but achieving clean, efficient object-oriented design is another one.

Transforming the buzzwords of "encapsulation", "reusability", "modularity" into workable and efficient solutions requires way more work than strictly learning the language.

Also, a common pitfall is to believe that you can do whatever because some garbage collector is taking care of memory management.

Before even reading whatever about java, I'd strongly recommend :

- of course, Design Patterns, by Erich Gamma et al;

- Principles of Object-Oriented Software Design, by Anton Eliëns (online version here).

As far as portability, the older version of Minix (1.5) runs on 68k (Amiga, Atari, and Macintosh) and SPARC, as well as x86 (32- and 16- bit). However, the 6502 used in the Apple 1/2/3 series is quite a bit more primitive than even a MMU-less x86 or 68k. In particular, fewer and smaller registers means more swapping to memory, which in turn reduces speed and increases code size. The 16-bit version of the 6502 used in the IIgs would be somewhat better than the 8-bit 6502s in the older Apples, but maybe not by enough. Also, Minix uses a microkernel architecture, which is all very nice from a theoretical standpoint, but causes a severe performance hit on really old hardware.

Is Minix on IIgs possible? Theoretically yes, since it's a Universal Turing Machine*. However, it's unlikely to fit within the extremely limited memory and speed constraints. Crafting a new OS from scratch would probably be much easier. But yes, it would be damn cool.

(*Yes, a UTM is assumed to have infinite storage space, so for theoretical purposes I'm assuming that we can hook a 6502 IIgs up to 512MB SDRAM or something.)

Never underestimate the bandwidth of a station wagon filled with backup tapes.

This is a statement by Andrew S. Tanenbaum from his book titled Computer Networks. Though it's supposed to be a text book (with 4.5 stars on Amazon.com), I and most of my friends also regard it as a nice collection of stories related to computer networks and communication ;-)

Back in school we always had a saying, "Never underestimate the bandwidth of a station wagon filled with backup tapes." Seems like that still holds true.

to the one os no one has ever tried to hack

security through... um... obscurity ;-)

Same holds for Awari, an ancient African game. The first computer program being able to play it at all is less than a year old. Try playing it yourself here.

I think this still does not qualify as AI, though.

Scott McNealy said that, but the vision was implemented by others. CMU's Mach (1985), Andrew Tanenbaum's Amoeba (1986), and Plan 9 (1987) were OSes that made a network into a computer.

To be fair, Sun does have ChorusOS , but that seems to have died the death (i.e. gone Sun Public Source) despite Scott's best intentions.

mirrored

njoy (long live university pipes)

btw, it looks kinda..well..dull

A simple search on Google would result your answer, but in the spirit of helping, you could look at Minix.

You are both correct and incorrect. While it's obviously not possible to simply go through changing instructions, operators and operands without consideration as to the effect on the program, it is possible to leverage functionally identical instructions to represent a bit.

If you read the article, a trivial example would be subtracting -5, rather than adding +5. The presence of a subtraction operation, rather than an addition operation can signify a binary digit.

Unfortunately, due to the consistent output from compilers, this is not steganography - you can both tell that the executable has been altered, and read the message! His plans for the future (parameter organisation, etc.) may be more relevant, but at the moment this is a proof of concept implementation, not a usable system.

Anyone interested in other forms of steganography could do worse than to read Andrew Tanenbaum's page on the subject.

Minix is Andy Tanenbaum's OS... the relation was that Tanenbaum has been highly derisive of Linux from the start for having a monolithic kernel... you'll find comp.os.minix posting of "Linux is obsolete" since 01/92 by Tanenbaum. He highly touts his microkernel design, but has done his fair share of spreading FUD against Linux. Minix has its own license and seems largely to have been a reverse-engineering of the UNIX concept into microkernel form. Linux was done in the same style, but with a monolithic form. *shrugs* http://www.cs.vu.nl/~ast/minix.html for more info on Minix.

I would like to take this opportunity to thank Linus for producing it. Before there was Linux there was MINIX, which had a 40,000-person newsgroup, most of whom were sending me email every day. I was going crazy with the endless stream of new features people were sending me. I kept refusing them all because I wanted to keep MINIX small enough for my students to understand in one semester. My consistent refusal to add all these new features is what inspired Linus to write Linux. Both of us are now happy with the results. The only person who is perhaps not so happy is Bill Gates. I think this is a good thing.

Thank you for showing me sanity.

And I'll also kind of ignore that the first few versions of Linux were published on the comp.os.minix newsgroup.

I will give you that MINIX is mispelled.

May I humbly suggest the good Dr Andrew S. Tanembaum ?

As well as being the creator of Minix (which in some senses can be considered the natural predecessor of Linux) he has written some of the best introductory computer science books around.

If you haven't read his pithy tomes on Computer Networks or Modern Operating Systems then you really ought to check them out.

Anyone who might feel inclined to disregard him because of that old spat with Linus should take a look at this entry in his FAQ:

What do you think of Linux?
I would like to take this opportunity to thank Linus for producing it. Before there was Linux there was MINIX, which had a 40,000-person newsgroup, most of whom were sending me email every day. I was going crazy with the endless stream of new features people were sending me. I kept refusing them all because I wanted to keep MINIX small enough for my students to understand in one semester. My consistent refusal to add all these new features is what inspired Linus to write Linux. Both of us are now happy with the results. The only person who is perhaps not so happy is Bill Gates. I think this is a good thing.

Well... Andy Tanenbaum, author of MINIX (on which Linux was based) once wrote a cook book called How to Prepare Your Input! So the Linux-Cooking connection is certainly there!

Well... Andy Tanenbaum, author of MINIX (on which Linux was based) once wrote a cook book called How to Prepare Your Input! So the Linux-Cooking connection is certainly there!

Well... Andy Tanenbaum, author of MINIX (on which Linux was based) once wrote a cook book called How to Prepare Your Input! So the Linux-Cooking connection is certainly there!

I decided to mothball my BeBox until it's worth at least as much as what I paid for it originally, taking into account inflation, etc.. :)

-adnans

Here is one of the sites we used for new ideas in my CS class at cmu

http://www.seanet.com/~brucemo/topics/topics.htm

Here is another one

Enjoy

Funny you mention that. I just heard a local public radio blurb about a Cincinnati company that is applying this to multi-perspon emergency worker and police radio communications and conference calling. Here's an article (not from the same comapny) about using this for cockpit displays. A PDF about NASA research on the subject. (Goes into exactly how we can fool the ears into spatial localization.) A chapter from a book about auditory cueing using spatial localization.

Most of this seems to be geared towards increasing Situational Awareness in the context of aircraft cockpits.

• Linux Kernel 2.2 (with low memory i would recommend 2.2..) or a really stripped-down 2.4 kernel, running a modern distro which is rather slick in itself, like Slackware or Debian. This will help you avoiding numerous security holes in older distros.
• There has been an article which focusses on small yet functional destop programs.
• If you want to go with really stripped-down distros, which are suitable (or optimized) for embedded computers, check this link.
• I have to agree with some of the other posters that one of the *BSD derivates can be and feel a lot smaller than full-featured, KDE3-based Linux distros...
• If security is not much of an issue for you, for whatever reason, you might want to go for an outdated Linux distro. Watch out for a 2.0 or 2.2 kernel, and libc5 instead of glibc2/libc6, or you might not gain much from the old stuff... Or even Minix? VSTa?

I implemented a quite similar feature in VLC one year ago. See this or this.

Since Minix has been put under the BSD license since April 2000, I wonder why nobody has made an effort yet to port it to embedded systems (PalmOS PDAs with Dragonball CPUs, for example, should be an ideal target). Minix should be much better suited for many embedded applications than the much more complex Linux kernel.

Minix is owned by a book publisher, and you needed to deal with them if you wanted to do anything with Minix. If you just wanted to be legal to use Minix you could buy a copy of the book, but anything else (trying to distribute on CD-ROM for example) was pretty much impossible.

Actually Minix was finally relicensed under a BSD-like license recently, albeit 10 years or so too late.

Maybe you guys are too young to remember, but back about 12 years ago, the only way you could get Unix on a PC was shell out thousands of dollars for Interactive Unix or AT&T or $99 for Mark Williams Unix which used the intel small memory model (ram was limited to 64K, yes 64K).

Doesn't Minix count as a way to get UNIX on a PC? It was released in 1987, was/is free, and ran on PC's.

Last year I have cooperated in restyling the course Self-Organizing Systems. The teacher introduced me to this great massively distributed language, and it was an eye-opener. Together we have designed some fun exercises around some of the basic self-organizing properties which can be shown with StarLogo.

The students (freshmen) gave better ratings for the course after our restyling. Also, some more enthusiastic students have helped us with designing some new StarLogo apps. A real great tool for this course!

More information about our course at the Vrije Universiteit, Amsterdam.

Last year I have cooperated in restyling the course Self-Organizing Systems. The teacher introduced me to this great massively distributed language, and it was an eye-opener. Together we have designed some fun exercises around some of the basic self-organizing properties which can be shown with StarLogo.

The students (freshmen) gave better ratings for the course after our restyling. Also, some more enthusiastic students have helped us with designing some new StarLogo apps. A real great tool for this course!

More information about our course at the Vrije Universiteit, Amsterdam.

There's actually a cool Amoeba out there for anybody into experimental OSes.

Except that Linux won't run on a 286. Perhaps you're thinking of Minix?

It's a shame that /. seems to think "Go To Considered Harmful" is Dijkstra's signature achievement. He was profoundly influential in developing the theory of operating systems. He was one of the first proponents of layered design. He also did pioneering work in mutual exclusion (IIRC, he invented semaphores) and deadlock. In short, he is responsible for a lot of the fundamental concepts that we use to build complex systems today.

I have no doubt that if you want to have a more theoretical background on many subjects regarding Computer Science, you have to read (or, at least, take a glance at) Knuth's The Art of Computer Programming.

His books give an excellent introduction to many subjects, including many of the hardest problems in Computer Science. The first volume of his "The Art of Computer Programming" gives a very concise and comprehensive review of Mathematics needed for the remaining volumes. You might even learn about mathematical objects you never heard of (if you don't have higher education in Mathematics).

If you need something ligther on the Mathematics needed for Computer Science, then you might want to read his "Concrete Mathematics". Quite a beatiful book (typographically speaking), with an outstanding expostion of some advanced topics in Mathmematics neede for Computer Science and also quite funny to read.

I should also mention that his books are also a prime example of how someone should write a book. His books, while mostly technical, show a clear style of writing, direct and also entertaining, while discussing deep subjects.

The "problem" with Knuth's books are that they are intended for serious readers. You know if you are serious if you can read the first pages of his first volume. :-)

Another book that I would recommend is Andrew Tanenbaum's "Modern Operating Systems" (which is a bit more practical than Knuth's books) gives an overview of the structure of some common Operating Systems, including DOS and Unix.

I could give you many other recommendations, but you'd have to specify if the other recommendations that you want are more practical or more theoretical.

I hope this helps.

The following two are the only ones relevant:

• Parsing Techniques—A Practical Guide
• Parsing Resources

Stepan Kasal

Parsing Techniques - A Practical Guide
Flexible Parsing
Workshop on The Evaluation of Parsing Systems
Robust Parsing
Parsing Resources

Probably the last one on that list would be the most useful starting place...

I found this on google: Amoeba WWW Home Page

This seems to me to be a unique way of sharing data, since it isn't machine centric. Rather, it focuses on the user and the user's data. I have no experience with Amoeba, but on the face, it seems to answer this person's question.

My question is this: Why has interest for Amoeba dried up? (Or has it?) What with the proliferation of alternative OS'es over the past few years, why hasn't Amoeba caught on?

I'd like to draw your attention to the Globe Distribution Network (GDN), like OCN, a content distribution network for freely redistributable software. Its design specifically addresses the problem of deviants abusing the network to distribute other people's copyrighted works and illicit content. In particular, it requires all content published to be digitally traceable to the publisher. If, after publication, someone finds that this content is not free software the content will be removed and its publisher blocked from the network.

The GDN furthermore offers a scalable solution to the problem of finding the nearest replica (i.e., a scalable URI resolver service in OCN terms), and facilities for dynamically replicating content in areas with many downloaders.

Publications on the GDN, the underlying Globe middleware, and its initial implementation (BSD license) can be found on http://www.cs.vu.nl/globe. The best description of the anti-abuse measures of GDN are found in the paper titled ``A Law-Abiding Peer-to-Peer Network for Free-Software Distribution'' published at the IEEE NCA'01 Conference.

What? Huh? Alright, let's look at this, shall we?

"A full 92% of their employees are under the age of 25."

Where did you get that? I didn't see a link to any meaningful data, so I have no way of believing that one!

"Which means they have all grown up in the geek culture where television, radio, and Internet are all free or subsidized."

I would hardly call that geek culture, more like modern culture.

"What Microsoft has done here is not so different from what Linux Torvalds did to Minux. Just as his actions drove Minux out of business, so too will Microsoft proceed to drive Linux into the ground."

This was my biggest WTF? How can you possible compare the two? Linus developed a kernel based off Minix. Minix still is around, check http://www.cs.vu.nl/~ast/minix.html but I didn't think they sold Minix. Regardless, Linus created Linux to be a better Minix, but not to compete against it. There was no reason then or now to compete. It is a matter of doing something that he likes, and a whole horde of other programmers like, to do. Write code that works!

MS doesn't want to compete, either. But for different reasons. They don't want to compete because that cuts into their profits. Much easier to have it set up so consumer money flows from the paycheck to the MS coffers without having a chance of getting spent elsewhere. And if there is a choice, why, the consumer might not spend money on MS at all!

The beauty of the OSS or GLPed or any "free" software is the consumer doesn't have to spend money on it to make it work for him.

MS can't drive Linux to the ground because there is no company to drive to the ground. Linux can only be stopped by MS buying laws to prevent programmers to work on it and to distribute it. Or by a huge schism of the Linux faithful. But even then, Linux will mutate and survive, simply because there is no one company in charge of it. If Linus kicked the bucket right now, Linux will still go on as long as someone wants to work on it. And as of right now, there are a lot of people that want to do just that.

"In the end, the winners are the users. For us, things just get more free and easier to use, which is what technology is all about. Empowerment to be our best."

Which are the OSS and Free software ideas. Freedom to choose. Freedom to become our best.

MS is trying to stop that. They want one choice, and that is no choice but them. That's that whole point. Choice. MS is doing their best to make sure that the average consumer will never, ever use anything but MS programs. Their whole OS is being inundated with superfluous programs. MSN Messenger. Windows Media Player. IE. None of this has to do with an operating system and everything to do with market lock in.

And MS will do *anything* to make sure they have market dominance. Even steal other people's code.

> And where is that snobby professor now? "Dunno" you say? That's what I frickin thought.

I think it's Andrew Tanenbaum and he is Amsterdam now, as far as I can see on his homepage :-)

Sorry, but Minix is already taken.

MINIX is a free UNIX clone that is available with all the source code. Due to its small size, microkernel-based design, and ample documentation, it is well suited to people who want to run a UNIX-like system on their personal computer and learn about how such systems work inside. It is quite feasible for a person unfamiliar with operating system internals to understand nearly the entire system with a few months of use and study.

MINIX has been written from scratch, and therefore does not contain any AT&T code--not in the kernel, the compiler, the utilities, or the libraries. For this reason the complete source can be made available (by FTP or via the WWW).

This is one of the courses I followed at the university, during my artificial intelligence study.
Lots of examples of this book, came back in our practicums, there are nice links to sites about this subject on the page and also the complete course is online for you to download (not sure if my professor is going to be happy about this, but who cares, I passed the grade:)

This is one of the courses I followed at the university, during my artificial intelligence study.
Lots of examples of this book, came back in our practicums, there are nice links to sites about this subject on the page and also the complete course is online for you to download (not sure if my professor is going to be happy about this, but who cares, I passed the grade:)

In Modern Compiler Design the advantages of compiling your compiler in the language (system) you are developing are summarized as this:

first, basic sanity check because it shows you're compiler and language are at least able to do work together

second, an extended sanity check because typically a compiler is a BIG program. This means not only small test-programs will be compilable, but also a real-world, large-scale application.

They mention as a possible disadvantage that there might be a danger that the language will be a bit biased towards creating a compiler. However, in case of C# (where the language is already defined) this is not the case of course.

As long as Linus keeps multimedia and extraneous "features" out of the kernel. As in Operating Systems Design and Implementation by Tanebaum, the author of Minix, I tend to think that compartmentalization is safer from a system security and integrity POV, but hardware threads are nice. The only things that should reside in kernel-space are drivers and system functionality. I can't even see justifying IP stacks in the kernel since that could run on top of the ethernet or whatever is underneath because a layered approach can install/remove/restart parts of the system w/o killing the whole thing. Btw, MINIX starts in less than 1 sec from a HD on a 486. And pretty darn stable too, except for the lack of preemptable kernel processes. I suggest running it on Bochs.

Multimedia codecs should remain where they should be, in libraries.

Has anyone heard of Plan 9 or Amoeba? Plan 9 is open source and is developed by Bell Labs (i.e., the same people who introduced Unix). Amoeba was developed by Tannenbaum. These have been around for several years and have not caught on yet. I think the reason is because there is nothing to be gained by the home user. Why would someone want people around the world using their computer when they were away? Just thinking about the security risks alone would make me skeptical.