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Actually, the page an non-equatorial elevators you are looking at is a bit out of date. There is much more recent material in the paper I presented at the 3rd annual space elevator conference. The slides are also available here. The paper should give you a quantitative idea of what the situation is.

To put into perspective what the previous post says. Moving a bit off the equator is possible and costs nearly nothing. On the other hand, if you want to place the Space Elevator in the continental USA, you are going to have to significantly increase the tension at the base of the space elevator, for a given payload.

The reason for this increase in tension is that as you move further away from the equatorial plane, the elevator ribbon starts being inclined at the anchor. The vertical component of the tension needs to be able to lift the desired payload, so the total tension in the ribbon is greater. This gets really bad as the inclination of the ribbon nears 90 degrees (at a latitude of about 48 degrees for the standard Edwards ribbon parameters).

Check this link out. It'll blow your mind how a space elevator not anchored at the equator is possible!!!

Indeed, there have been several incarnations of parallel Matlab. One of them is (Star-P) is almost at the level of commercialization.

...a novel concept.

And now there's Microsoft One Note.

DotNet does not work as advertised (EG: have you seen any commercial apps in it?)

- Dell's Website
- MIT's iLab and ShuttleTrak services
- T-Mobile's customer portal
- Infragistics website and software solutions
- Any one of the items listed in Microsoft's .NET connected directory

Or perhaps you would like to look at the massive amount of work that has gone into emulating the .NET framework with the Mono project? No, .NET is completely unsuccessful (BTW, I wrote and run an ecommerce application for my company of employ on .NET that does over $20k/day in business. Sounds like production quality to me.)

Last week, Dr. Drew Endy from MIT gave a talk to the University of Washington's CSE department on Building Biological Systems (PowerPoint slides are here).

At first glance, building biological systems seems like a pretty daunting task. You have all of these As, Ts, Gs, and Cs, and your task is to figure out how to order them to make your system work as specified. And unlike computers that were engineered by humans, the biological mechanisms that work on DNA aren't completely understood.

However, a promising method of engineering biological systems is to abstract them into systems, devices, and parts. One of the interesting things they're doing is building a repository of biological parts, available at http://parts.mit.edu/. These parts use a standardize way of communicating with each other, allowing you to combine them easily.

Using these parts, college students are able to engineer biological systems in a single quarter. In fact, there's been a few intercollegiate biological engineering competitions, linked to from the MIT Parts site.

Last week, Dr. Drew Endy from MIT gave a talk to the University of Washington's CSE department on Building Biological Systems (PowerPoint slides are here).

At first glance, building biological systems seems like a pretty daunting task. You have all of these As, Ts, Gs, and Cs, and your task is to figure out how to order them to make your system work as specified. And unlike computers that were engineered by humans, the biological mechanisms that work on DNA aren't completely understood.

However, a promising method of engineering biological systems is to abstract them into systems, devices, and parts. One of the interesting things they're doing is building a repository of biological parts, available at http://parts.mit.edu/. These parts use a standardize way of communicating with each other, allowing you to combine them easily.

Using these parts, college students are able to engineer biological systems in a single quarter. In fact, there's been a few intercollegiate biological engineering competitions, linked to from the MIT Parts site.

The frightening thing is, lispms from the 80's enjoy quite some popularity among certain people where I work. They really are amazing machines, and those who use them regularly feel strongly that there hasn't been a more usable environment in all the time since they were created.

Let me tell you, though, as a sysadmin, these things can be a royal PITA. Not because there's anything wrong with them (well, except maybe for their complete lack of security) but they're just so different.

There are still many copies of The Lisp Machine Manual lying around, including an early rant by RMS against the recent trend of software hoarding. It makes for an interesting read...

noah

It is such a shame that C-based languages took over the computer world in the 1980's. If we had followed the Lisp path instead things might be so much better. C++ with all of the template, RTTI, and STL grunge is such a half-assed imitation of powerful Lisp constructs that have been perfected for 15 years. I won't even go into Java, Python, C#, PHP. What a waste. I suggest you non-Lisp programmers grab a copy of SICP and start over.

If On Lisp is the best programming book you have ever read, you have never read SICP .

If you're interested in a completely open-source robotics platform (where everything is open, including schematics, the firmware, the user libraries, *everything*), visit www.orcboard.org. There's no commercial manufacturer, but there's a community group-ordering effort.

The OrcBoard is used in the MASLab robotics competititon at MIT, and in MIT's cornerstone robotics class. Most folks use the OrcBoard with a linux laptop or embedded PC.

The OrcBoard is just the controller for a robot, not a robot itself, and can control a wide range of robot types and sizes, with lots of different sensor configurations. It's sort of a swiss-army knife for robot construction.

While I recognize that the paper represents legitimate research, it does bear an uncanny resemblance to those produced by the automatic paper generator, right down to the axis labels.

will be the first thing reversed.

It's high time the top brass of the environmental movement admit that stopping Nuclear power was a mistake that has lead to greater devastation of the environment by coal plants.

Even the nuclear waste issue pales in comparison to the the ecological damage coal plants have caused and will keep causing until we replace them (finally) with much cleaner nuclear technologies like Pebble Bed. Coal of course has it's own waste issues.

The anti-nuclear power movement has been one of the best examples of the law of unintended consequences in our times.

"Not to single out IT departments in particular, but I think the reason that these spreadsheets start up and grow is specifically that it's often difficult to get someone in another department to understand your needs well enough to make the tool that you really need. "

http://web.media.mit.edu/~lieber/PBE/

"What is Programming by Example?

Often, in computer interfaces, users wind up doing the same or similar sequences of operations over and over again in different situations. But if computers are so good at repetition, why is it that the users are the ones who keep repeating things?

Programming by example [or "programming by demonstration"*] is a technique for teaching the computer new behavior by demonstrating actions on concrete examples. The system records user actions and generalizes a program that can be used in new examples. "

If you mean they all have an algol-like syntax, then you're correct. However I don't know what you mean by "sugar for common control structures".

I mean something that highlights the logical structure of what's going on. The most trivial example is probably picking out sequential vs. iterative vs. conditional logic in algorithms. Of course you can do these things in LISP, via cond and such, but there's no particular emphasis on them; they just look like any other bit of LISP. I realise that this is necessary in a language that prides itself on simple-but-flexible syntax, and indeed that a lot of LISPers would argue that it's an advantage, but experience suggests that most programmers prefer something a bit more explicit.

Consider, for example, the loop example shown here (scroll down a page or so). While the Scheme code shown has power and a certain elegance, the same algorithm could have been written significantly more clearly and concisely in a language that provides syntactic sugar for list manipulation and pattern matching.

Apparently, you haven't really used Lisp, or you'd know that most things that are in standard libraries are handled internally by the language.

I don't know what you think counts as "most things that are in standard libraries", so I'm going to guess that you're talking about the minimalist approach taken by, say, C. I'm talking about the behemoth that is Java's standard library, or a rather more powerful approach like Perl's CPAN. Certainly something like Java's standard library is no demonstration of exemplary design, but the point is that for real tasks, it's often Good Enough(TM).

Also you'd know that you'd know that lisp provides hooks to use foriegn language libraries just like pretty much every other language.

Sure. And I also know that in the real world, you usually want imported libraries from other languages to be the fall-back if you really need it and not the primary means of increasing functionality. It's almost invariably a hassle to set it up compared to using something that fits in with your native language.

Name control structure that doesn't exist in Lisp.

It's hard not to give a loaded answer to that involving loops and side-effects. My point wasn't that you can't do it, my point was that doing it is "nothing special". You might argue that this is an advantage, and for skilled LISPers you may well be right; I'm talking about average programmers working on typical projects.

Flexible-but-underpowered is why almost no-one writes new applications in C any more.

And with that statement, you lost all credibility.

I take it you disagree, then? Obviously I'm only one data point, but I live and work in a very high-tech area, and both I and quite a few of my friends are professional software developers. Lots of us use C++, quite a few use Java, many of us using $SCRIPTING_LANGUAGE_OF_CHOICE either for utiliities or for web work, but I don't know anyone who's working in C any more, aside from a couple of specialist embedded projects.

Can you name a few major development projects that have been started in, say, the last five years, that use C for reasons other than being tied to it by compiler availability on the target platforms? Do you think there are anything like as many as there are in, say, Java, C++, or Visual Basic?

And since Aspect-Oriented programming is a patented technique, basically nobody can legally use it unless you're a personal friend of the inventor.

So, who really cares if its theoretically any good, when legally it is worthless?

Patent here

An MIT prof just released a new book that you can read online called Democratizing Innovation. I haven't read the whole thing yet but it looks like he may be on to something. Also see Pro-Am Revolution .

The MIT student newspaper publish the RIAA complaint today . They listed the IP numbers, dorm address, song titles, but not students names.

Both of these ideas raise interesting issues about what "modular" means, and if this is an important idea. The name and the product are catchy and interesting, so I think it is worth figuring why this concept has arrived now, and what it may lead to. This even has some implications for studies of mind that trying to do some serious empirical science into the nature of the brain/mind by understanding the architecture. This is a pretty hot field of research, so it's nice to see some terms that fit into scholarly papers and fancy academic books being applied and marketed. I just hope this hits it. Judging by the recent attention given to the Mac Mini and recent advances in wearable and implantable computing devices this is at least going to becoming even more interesting discussion in the coming months and years.

I don't really think fabric integration is necessary. I can think of several good reasons to have the electronics seperate from the clothing itself (security checkpoints, not having to replace your entire wardrobe, etc.). I would prefer strategically-placed pockets and conduits, like the Scott e-vest instead. Or better yet, this, except more elegantly packaged. I would also design it so that some pieces could get worn on the legs, instead of having everything on the upper body.

Besides, even with electronic fabric, you're still going to have little boxes; hard drives and larger integrated circuits aren't thin or flexable.

http://www.dspace.org/

"A groundbreaking digital repository system, DSpace captures, stores, indexes, preserves and redistributes an organization's research material in digital formats."

http://helium.knownspace.org/whyknownspace.html

"KnownSpace is a data manager---something that can help users build, organize, reorganize, annotate, search, mine, visualize, and navigate large, heterogeneous, dynamic data spaces. The aim is to provide a uniform platform for researchers around the world to develop and disseminate software to provide better interfaces, more intelligent applications, and more sophisticated and uniform networking---all for free, with source code easily changeable and available to anyone."

A possible front-end.

http://haystack.lcs.mit.edu/index.html

Different Dvorak, dumbass ;) Hope you were joking... Which in that case, I'm the dumbass.

If you don't want it, don't compile it i

Sure, that's the default answer. But, I don't know much about the Linux kernel, so allow me this little speculation:
How is the kernel affected by desktop requirements? How does enterprise use vs. game use shape issues like memory, and threading? Are there any issues vis-à-vis these differences? That's an interesting question, in which case, if there are, would there be an impact, since there is fundamental design interdependece between them? Here's an interesting paper by MIT (and the abstract):

Maintainability of the Linux Kernel
Schach, Jin, Wright, Heller & Offutt

"We have examined 365 versions of Linux. For every version, we counted the number of instances of common (global) coupling between each of the 17 kernel modules and all the other modules in that version of Linux. We found that the number of instances of common coupling grows exponentially with version number. This result is significant at the 99.99% level, and no additional variables are needed to explain this increase. We conclude that, unless Linux is restructured with a bare minimum of common coupling, the dependencies induced by common coupling will, at some future date, make Linux exceedingly hard to maintain without inducing regression faults."

Also:
Categorization of Common Coupling and Its Application to the Maintainability of the Linux Kernel, by Liguo Yu, Stephen R. Schach, Kai Chen, Jeff Offutt, IEEE Computer Society
http://csdl.computer.org/comp/trans/ts/20 04/10/e06 94abs.htm

"Data coupling between modules, especially common coupling, has long been considered a source of concern in software design, but the issue is somewhat more complicated for products that are comprised of kernel modules together with optional nonkernel modules. This paper presents a refined categorization of common coupling based on definitions and uses between kernel and nonkernel modules and applies the categorization to a case study. Common coupling is usually avoided when possible because of the potential for introducing risky dependencies among software modules. The relative risk of these dependencies is strongly related to the specific definition-use relationships. In a previous paper, we presented results from a longitudinal analysis of multiple versions of the open-source operating system Linux. This paper applies the new common coupling categorization to version 2.4.20 of Linux, counting the number of instances of common coupling between each of the 26 kernel modules and all the other nonkernel modules. We also categorize each coupling in terms of the definition-use relationships. Results show that the Linux kernel contains a large number of common couplings of all types, raising a concern about the long-term maintainability of Linux."

MIT Open Courseware is an example.

Compuserve did not "hold the patent", Sperry (by then Unisys) did. Compuserve merely licensed the patent. See, for example, amongst many other web resources, http://www.kyz.uklinux.net/giflzw.php and http://lpf.ai.mit.edu/Patents/Gif/Gif.html Just being pedantic, but the idea of Compuserve ever coming up with something patentable was mind-boggling...

Eric is a great teacher - I took a graduate course with him on Innovation Management (15.356) a few years ago. The course was recently renamed "How to Develop Breakthrough Products and Services" and is available via MIT's OpenCourseWare at http://ocw.mit.edu/OcwWeb/Sloan-School-of-Manageme nt/15-356Spring2004/CourseHome/index.htm. The course home page also gives a very brief overview of Eric's lead user concept. It's one of his pet ideas, and although it isn't the sole focus on the course, it certainly is one of the foundations.

The actual class was wonderful: a mix of working scientists and R&D executives, Sloanies and other MIT grad students, and a couple of undergrads sitting in. Lots of student interaction and learning from your peers. The individual project was a good experience as well - I wrote a paper analyzing why Lockheed's X-33 space plane project failed, and what could have been done so that the the technologies developed (autonomous navigation and landing, composite materials, linear aerospike engines, metallic thermal protection system) didn't die with the project. Eric gave lots of guidance and advise on the analysis.

http://simile.mit.edu/piggy-bank/index.html

"What can I do with this?

You can harvest and save useful metadata about the pages your browse directly from your browser and then browse and search it thru a built-in facetted browser.

Think of bookmarks on steroids."

There have been some very good research projects done on how to build a more secure system, and some of the most amazingly effective ones have been the ones that challenge the basic assumptions of "best practice".

MIT Kerberos takes the view that no machine on the network can be implicitly trusted; access to network services is controlled by tickets, mediated by a ticket distribution service with which each user and service has a pre-shared key. This works even for systems in which the local operating systems have no internal access control mechanisms whatsoever.

Capability-based systems essentially throw out the classic security model of users, roles and permissions, replacing them with a system of nonforgeable references by means of a combination of memory protection and cryptographically strong naming.

Finally, people need to come to terms with the fundamental fact that content-based security schemes are a losing proposition (1, 2). Virus scanners, adware scanners, porn blockers, spam filters, and even national customs departments all face the same problem: they can only inspect what goes by and apply a list of tests to winnow bad items. There is strong economic pressure to find ways to bypass these types of checkpoints, so new tricks are constantly being invented, only to be compensated for by the guardians; thus the guardians are always a step behind.

This is not true. It might work on Kazaa but most other P2P networks use MD5 or better. Okay, they have found collisions but no one has found a way to generate file for a given key.

SHA-256 looks like it's the way to go for now. However, if you are now designing a system which is intended to last a number of years that needs to use hashes to determine if two items are the same, then I would suggest that you use two unrelated hash functions to do the job. This is especially true if anyone else might have an incentive to fool the system.

Being a student currently taking MIT's 6.170: Lab in Software Engineering, I would point people to this page: http://www.mit.edu/~6.170/supplemental-info/docume ntation.html
And to http://web.mit.edu/6.170/ for the general class website.

Being a student currently taking MIT's 6.170: Lab in Software Engineering, I would point people to this page: http://www.mit.edu/~6.170/supplemental-info/docume ntation.html
And to http://web.mit.edu/6.170/ for the general class website.

"The thing is, though, I'm not just saying "needs skilled labor" as in "this is how it is right now"; I'm saying it as in "every attempt for the last 30 years to enable suits to do this kind of thing [creating application logic] unassisted has failed", starting with COBOL."

Programming by Example.

John Underkoffler came from MIT's tangible media group

Zen and the Art of Search, it seems.

Indeed. It's too bad that most of the comments have been cracks about his name or his new title.

Gary Flake's The Computational Beauty of Nature is a classic book that anyone interested or active in engineering or computer science should own and cherish. Not only is it the best introduction and overview to explore and link together a number of popular but often confused concepts, from Fractals and Chaos to Number Theory and Computer Science, it is a beautifully written and presented book itself - perhaps best compared in both subject matter and style to other classics like Douglas R. Hofstadter's Gödel, Escher, Bach: An Eternal Golden Braid, or perhaps A New Kind of Science by Stephen Wolfram - except that it is shorter and much more accessible for even the layperson to read.

I had no idea what he has been up to lately. That he had left NEC to join Overture and become head scientist for Yahoo! Labs and eventually over to MSN Search certainly seems to fit the billing of "News for Nerds. Stuff that Matters." better than most stories I read here. My thanks to the submitter and editor for posting this.

Clocky is a clock for people who have trouble getting out of bed. When the snooze bar is pressed, Clocky rolls off the table and finds a hiding spot, a new one every day.

> How is this different from the RIAA going after its infringers?
> In both cases, they're intellectual property violations.

Not even close, although it will take a bit to explain.

First, "Intellectual Property" is an oxymoron, a term used by those that wish to to make copyright, patent and trademark laws even more restrictive, for the purpose of drawing analogues between ideas and physical property and advocate ownership of ideas that would somehow make thought and expression restrictions palatable.

However, there are fundamental differences between these concepts. I could repeat the common scarcity and exclusivity arguments but instead I'll remind you that when your ancestors sat in their caves around the fire, eating barely cooked wooly mammoth meat - stories, songs and ideas how to make better hunting or farming tools were shared freely but not necessarily the actual tools.

When copyright and patent protection were devised, the purpose was to benefit society, by granting limited monopolies to allow the creators to recoup their investment before releasing the works into the public domain.

Unfortunately, laws can be bought and original intent can be circumvented (does a protection term of >100 years benefit society? how?). Therefore, one should not confuse legality with morality (this is actually not a new concept; read Sophocles for an example).

So here's the beef:

**AA and their ilk purchased legislation that allows them to rob society of what should rightfully belong to the public. Their excercising their rights under that legislation is legal, but not necessarily moral.

The GPL, on the other hand, is an effort to use the only legal means available to keep free things free. The law is imperfect but no other alternative exists.

I'll try to give an example from the physical world but it may not be perfect since, as I said above, the dynamics are different.

Say I am an artist, I paint pretty decent art and I want as many people as possible to appreciate and enjoy it. So I take all my art, put it in the town square and invite people to freely take some. However, what would stop a person from grabbing all of it, locking it in his basement and charging people who want to view it?

Enter the GPL. It says in simple words that, under the present laws, you don't have any right to distribute the work. However, you can have this right, gratis, if you agree not to abuse it.

Clearly a philosphical agrument is lost on the nerds who frequent this page. For some odd reason we require practicle applications of technology, such as a, USB controlled disco dance floor.

Hmm, I have the distinct impression that this author has read yesterday's article and used the Automatic CS Paper Generator to produce this article.

It has the same superficial flow of words, non-statements and not-touching-the-point style as the examples it generated for me.

The MIT Swapfest, aka The Flea at MIT, is a great place for old or junk computer or radio parts. I've heard somebody tagline it as "Yesterday's technology, today!"

Third Sunday of every non-winter month, next flea is the first of the year, this Sunday April 17th.

Well, a bunch of searching leads me to believe the patent is trivial. Having stated that, it's worth mentioning that another patent (search for Stac on the page), 5,016,009, was also involved in the case, but I can't seem to find an actual copy of the judgement (it's probably on Lexis Nexus) to know how much basis it had on the ruling.

So, Microsoft never had a hold on the patent. It just happened to reinvent for a fourth time time (Waterworth, Ross, Gibson/Graybill, and Microsoft) the same idea. That's a pretty good clue that that patent shouldn't exist or be a basis for why Stac won. If you have any more information, I'd be glad to hear it.

Generate one automagically here and see if it is accepted.

Check this tool out.

It will contain songs in the form of programs which can change every time they're played. One idea is to create a real-time life remixer, which takes input from a microphone, and plays it back in 'some mangled form'. So, you're walking down the street with your headphones on. The box is taking in the noises of cars going past and people talking, and it's spitting some kind of remixed interpretation of the sounds into your ears. from Engadget

Any effort, gesture, event, etc is meaningful at some levels of abstraction but not others. Once you accept and wrap your mind around that, and understand that there are levels of abstraction on which our conciousness is not only meaningless but does not exist it becomes easier to move beyond philosophy to practical reality.

I wouldn't use the term "levels of abstraction", as it misleadingly suggests a hierarchical one-dimensional relationship. But yes, there are points of view or perspectives in which consciousness is meaningless or non-existant.

As the Discordians put it, "All statements are true in some sense, false in some sense, meaningless in some sense, true and false in some sense, true and meaningless in some sense, false and meaningless in some sense, and true and false and meaningless in some sense."

This is not a realization to "move beyond", it is the foundation of liberation. Though yes, another part of liberation is not getting stuck there, getting back to "chopping wood and carrying water". (So the Zen master should come hit me with his stick right about now, eh? :-) )

At the levels of abstraction where it is meaningful, focus is not subjective. Focus IS a chemical state.

If focus is not subjective, not an experience that you are having, why do you care about it? Are you just making your brain chemistry fit a certain pattern as a party trick to show your friends?

Somewhere in there is presumably a subjective experience you're trying to alter. Whether you call that "focus" or "recognition of focus" or "recognition of recognition of focus" doesn't much matter. Though when most of us say "I'm focused on this" we're refering to our subjective mental state, not looking at EEG output, so I have to say your semantics are rather odd.

I'm reminded of a Raymond Smullyan piece, An Epistemological Nightmare, where an "experimental epistemologist" is unable to state his own beliefs without checking his brain-reading machine...

Again, it's a funny statement, but they didn't get it into a tough conference. And the point that they might be trying to make (that there is a lot of nonsense in computer science) is hard to prove. That was different for Sokal, because there is or was a lot of gibberish and hiding-behind-big-words in literature on postmodernism. But that's just my humble and certainly not well-verified opinion.

I'd have to say that this WMSCI is definately not run by a collection of academians. If you look at the conference acceptance letter text, the "General Chair" of the conference (or acceptance committee) signs his name Prof. Nagib Callaos. Now if this was a legitimate conference, the "General Chair" would at least have a PhD (not that that implies competence or legitimacy, per se but it is a good start). In any case, as the chair of a real academic conference you would not sign your name "Prof. whatever." "Prof." is a completely useless title. There are many people who can legitimately sign their name as "Prof. someone" but not nearly as many who can say "Dr. someone, PhD."

So really this is not a case of academians not understanding something but rather it is a case of pseudo-academians not caring.

Gore can claim he invented E-Voting. After all, his paper was published by MIT.

It gets worse... they submitted another paper that was rejected, they asked why, and got this in reply (several paragraphs, complete with random statistics, to say "it's too much work for us to tell you.")

or has it already happened?

downtown Holland, Michigan is in flames as a randomly assembled protest practices their own brand of metamoderation.