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I'm not talking about Python. Python is positioned as a scripting language, and hence doesn't have a powerful compilation infrastructure. Although, Pysco does some very cool dynamic optimizations for Python.

In contrast, there are many high-level languages like Common Lisp, Dylan, Scheme, ML, Ocaml, etc, that have very powerful native compilers. They do optimizations that C/C++ compilers simply cannot do, because of the low-level C memory model. Literally decades of research has gone into making these compilers, and they have optimizations that (while not quite magical) are very impressive.

Variously:

- There are type-inference optimizations that eliminate the overhead of dynamic dispatch.
- There are heap-analysis optimizations that stack-allocate objects whenever possible, to avoid heap allocation.
- There are analysis that avoid heap-allocating closures.
- There are analysis that eliminate type checking and array bounds checking.
- There are analysis that perform large-scale optimization of class heirarchies, to eliminate the over head of OOP.
- There are memory allocation analysis that reduce the overhead of garbage collection (region inference).
- They do method specialization, allowing the C++ template advantage of generic functions optimized for a given type, without actually having to deal with explicit type parameters.

Some useful pointers:

Apple Dylan Wiki
Lisp vs Java vs C/C++ performane
Bigloo Scheme Compiler
Gwydion Dylan compiler
CMU Common Lisp Compiler
UW Vortex Compiler
MLKit ML Compiler
Ocaml Compiler

and, when combined with booze, it's a treatment for stroke!

Interestingly, caffeine also seems to have a neuroprotective effect when it comes to Parkinson's (here's an article even the most java-addled ./er should be able to get through).

Also interesting: nicotine has an even stronger neuroprotective effect against Parkinson's. And what's really weird: smokers metabolize caffeine about twice as fast as nonsmokers (nobody's really sure why). Next time your pretentious smoker buddy starts bragging about how much coffee he cranks, you might mention this. He's got a biochemical advantage.

I don't smoke, and I wouldn't advise doing it as part of your health regimen, but nicotine's interations with caffeine are kind of intriguing.

Some claim caffeine helps for Parkinsons disease too

I read a bit about him a few different sites. Sounds like an interesting guy.

If you're having problems with that, use a different popup blocker

What is this popup you speak of? I still use pine for email (mostly because I'm a command-line curmudgeon). It's fast, robust & virus-proof.

Otherwise, it needs to deal with an explosion of different language feature combinations to do a good job.

...I don't think it was false at all, you answer how it would work in your 'Otherwise,' clause.

JIT certainly has a lot to still to offer, but there are still many applications that could benefit greatly from improved static optimistaion, in my opinion.

Anyway, I am also open to revolution as opposed to evolution, but I don't know what the revolution is that you have in mind. If you can give me an example of some program for which your revolutionary language + optimizer would do a better job than current state-of-the-art static compilation techniques, I would find that most interesting.

Beware, though, that there is a fine line between adding expressiveness to a language versus placing the burden of optimization on the programmer. An example of the former is strong typing, which goes a long way to helping the compiler with alias analysis. An example of the latter is #pragmas that tell the compiler how to do its job.

If you are interested, there is a language called ZPL that tries to help the programmer and optimizer work together more effectively. I think this is quite a good example of a language that does not simply put optimization burden on the programmer, but instead simultaneously eases the job of both programmer and optimizer.

"Those of you present who have lived with this field, and who have lived with and suffered with computing machines of various sorts, and know what kind of regime it is to invest in one, I'm sure have appreciated the fact that it appears that this machine has been completely assembled less than two months ago, has been run on problems less than two weeks ago, and yesterday already ran for four hours without making a mistake! Those of you who have *not* been exposed to computing machines, and who do not have the desolate feeling which goes with living with their mistakes, will appreciate what it means that a computing machine, after about two weeks of breaking in, has really a faultless run of four hours. It is completely fantastic on an object of this size; I doubt it has ever been achieved before, and it is an enormous reassurance regarding the state of the art and regarding the complexities to which one will be able to go in the future, that this has been achieved."

...can be found here (PDF file).

My but you're gullible... That claim is nothing but a myth debunked here That also makes my doubt your claims about volcanoes & decades.

Progress comes from testing new ways of doing things. Experience shows that most new ideas fail. (Consider -- for most problem areas, there are an infinite number of ways to be very wrong than close to correct.)

Yes things fail but so what? As I said, we wouldn't be where we are without trying and failing. Being scared of failure will simply result in no progress at all.

tried. The left non-capitalist methods have repeatedly had the same results as nazism, only worse...

Clearly a right-winger such as yourself (if you are indeed one) considers the so-called Communism worse than Nazism. But I'll bet that most people would consider Nazism to be worse.

(The left-wing people explain this like the christians explain all the horrors of religion, "it is not an error in the religion, only what men do when implementing it! Please ignore that part about eternal torture (/dictatorship by the 'people'), by the way!".)

But the difference is that WE learn from our past mistakes. Religion, on the other hand, doesn't. The difference is that religion is static while left wing thought is not.

I am, of course, willing to happily embrace a better way of doing things -- when a working society has been implemented, worked for a few decades and there are good arguments why it will continue to work. There are none now.

If you don't want to try changing society, that's fine. You'll just lag others. The day will come when others DO succeed. If you are a conservative and want to live in Plato's cave, that's fine.

I think it is difficult for you to see what change is necessary. You live in Sweden and it is one of hte top countries in the world. So the status-quo is very attractive to you. On top of it, it has some socialist ideals so the country isn't as badly off as USA (how many homeless are there in Sweden?). Unfortunately, the same cannot be said of the majority of the world's population. The vast majority of people on earth are simply economic slaves! Visit or read up on South America and see if the status quo there is good enough.

A "fun" fact is that all idealist (religious and political) theories I've seen on how to organize a society make assumptions on human nature and behaviour -- something we don't know enough about to predict(!) and most of which seems to change in a random fashion with the culture in each generation!!

That's not entirely true. In some cases it's true; in others it's not. Some people like to seperate econopolitical systems (like socialism, capitalism, fascism, etc) into two categories. One are UTOPIAN systems. The other is called (I forget the name so let's just call it) "pragmatic" systems. Utopian systems involve coming up with a notion of utopia and then building a system from that. The other systems involve no advanced conceptions but instead involve coming up with ideals on-the-fly. What you are referring to are utopian systems. An example of a utopian system is communism. This system assumes certain things about the world. An example of a non-utopian system is anarchism. Anarchism, for example, does not assume as much as you imagine. I'm not saying one is better than the other. All I'm saying is that not all econopolitical systems have built-in assumptions.

There are minimum levels of education and wealth to have a functioning democracy. I'd put the date for modern democracy somewhere after the first world war (women got the vote here in Sweden about then).

You DO NOT need minimum levels of ANYTHING for democracy!!! If you believe such a thing, you are nothing more than an elitist. Your argument is the same as those used by aristocrats several hundread years ago, and imperialists rul

A critical review of maglev trains and convention wheeled trains was presented in an attempt to identify performance advantages of maglev. Traditionally claimed advantages of maglev were not found to hold up to wheeled train systems incorporating similar non-contacting propulsion; however, performance advantages were identified for velocities greater than 500 mph (805 km/hr). At these high velocities, travel at atmospheric pressure is not practical, and so, an analysis was made for applications in tubes of reduced pressures.

The feasibility of a personal rapid transit (PRT) system designed with maglev suspension and for travel in tubes of reduced pressure was evaluated. The PRT maglev would have superior service capabilities yet no obvious technological barriers. An economic comparison to maglev train systems suggested that the PRT maglev costs about 40% less while providing appeal to a broader audience. Proposed performance advantages of the PRT maglev include reduced energy consumption, reliance on electrical power, and significantly reduced transit times as compared to air or train systems. A practical approach to implementation is presented and consists of initially using lower velocities, higher tube pressures, and PRT vehicles connected as train units. Proposed evolution of the system includes attaining higher velocities and incorporating superconductive elements in the rail embodiments.

The hard part is building and maintaining the integrity of such a huge global network of underground tunnels. That probably means we'll be waiting a couple decades for the nanotech breakthroughs that allows us to easily "eat" through miles of rock and then build-by-numbers bottom-up.

Imagine feeling weightless in your seat as your train approaches orbital velocity.

--

I really hate, I mean I - HATE - those god awful gianormous skyscraper towers that blast out 90dB of concentration breaking whirring and grinding sounds.

Hell, yeah! As I grow older my tolerance for this kind of noise diminishes, for some reason. I'm seriously considering buying one of those noise cancelling headphones for the times I have to work in the server room. Not only are there about 50+ machines plus switches/routers etc, each with multiple fans, but there's a couple of AC vents on the floor that are almost over the AC machine thingy and that thing is *LOUD*.

I might already have some Tinnitus (I have yet to go to the doctor) and I'm not taking any chances.

An M2P2 shield would provide propulsion and protection from radiation. Of course, thats too obvious for NASA to fund.

M2P2

-Mike

The answer is to design the Mars transit vehicle to carry its own magnetic field. Superconductors allow us to create fields of such strength that just about any cosmic ray will be bent to miss the spacecraft. Also, we can inject some local ions into that magnetic field, trapping them, and they in turn act as a partial shield against electromagnetic radiation (charged particles and photons have a nice high interaction probability). For more, and on even using such magnetic fields as a modest propulsion mechanism (interacting with Solar Wind), see this.

In the current incarnation, it is intended as a solar-sail like drive for very low-mass probes. However, attached to a larger mass, like an interplanetary vehicle of the scale suitable for human occupancy, it would barely impart momentum at all, which would make it unsuitable as a drive technology.

Though it would work wonderfully to shield the vehicle from the solar wind and other problematic radiation.

The crazy thing is, though a portable magnetosphere is so obviously a crucial requirement for trans-planetary travel, there isn't a single resource available through my above-average googling skills. The technology is either so far removed from mainstream mission planning circles, or...

I think you'll find that your questions will be answered by a look at this site. It's all about Mini-Magnetospheric Plasma Propulsion (M2P2). They do exactly what you are asking for (create an artificial magnetosphere), and supply some nifty propulsion to boot. And no, it doesn't require megatons of molten iron, as some other posters have suggested...

Pine has threading if you patch it. Mutt also has threading. In Perl programming, Mial::Box supports them.

Mulberry lets you sort by thread and also happens to be the best darn IMAP client I've used (except, perhaps, pine). Yes, it is a 5 MB download with no browser, but you get A LOT in those 5 MB. I still use Opera for my browsing, but I've been reasonably happy with Thunderbird, even if it hasn't hit 1.0 (their 0.4 is better than outlook, outlook express, or eudora). If I'm not the only PINE fan that is still kicking around, there is a fancy thread interface patch that is quite fun: http://www.math.washington.edu/~chappa/pine/info/f ancy.html

If forecasters got paid based on accuracy, they'd owe me money!

From Visual Displays FAQ

Low Vision Enhancement System
Display: B&W CRT
Resolution: 512 x 492 pixels
Field of View: 50 (H) x 37.5 (V)
Pixel Size: 5.9 arc minutes/pixel
Overlap: 100%
Weight: 2.1 lb
Price: $4,995 US (with 3 cameras)
Vendor:
Visionics Corporation
Suite 600
1000 Boone Avenue North
Minneapolis, MN 55427 USA
Tel: 1-612-544-4950/Fax: 1-612-544-4784

This has been done before, here and here.

Quit slashdot today: http://www.cs.washington.edu/homes/klee/misc/slash dot.html

Quoth the poster:

Do they prop open their eyelids and clamp their heads in place?

This very phenomenoa was written about a few thousand years ago.

Yes, this is certainly the case - the UW gliders (the original ones by the way) are doing open ocean work in the labrador sea and alaska right now. One of the gliders got stuck in an eddy for several days, and went around in circles trying to fight the current rather than use the current to go out the side of the eddy and then continue south. Some new code had to be sent to the glider, which then made its way out. Writing algorithms for "figuring out how to get from point a to b without an intimate understanding of ocean current prediction" isn't particularly easy. Want to see gliders tracked in realtime? Look here.

What is fascinating, in my opinion, is that Silbo Gomero is being used to help map the language sections of the brain. I found the abstract of a research paper on the topic, but unfortunately, can't find the paper itself. Can anyone else help me out there?

The gist of the abstract is that when a person knows Silbo and hears it spoken, the language sections of the brain turn on, but these sections do not fire in a person who does not know Silbo when they hear it. This helps separate out the true language sections from the pattern matching areas and the sound recognition parts. I for one think this is fascinating.

Even many experienced OO'ers will tell you that they use less inheritance and sub-typing than they used to, and instead use composition and aggregation, which are "less OO" concepts, and found in IBM's 1964 IMS database.

Even in geometry with its stable rules, we have the ellipse-circle fights and the square-rectangle fights.

Alan Borning proposed a neato object system where relationships among objects (it's prototype based) was handled by "inheritance constraints," a sort of super-flexible inheritance cum delegation scheme. See this page for Classes versus Prototypes in Object-Oriented Languages.

A funny thing happened on the way to building the SSC...

Actually, it's what happens AFTER the SSC is completed in a parallel timeline that's the subject of one physicist's (fictional) novel of how the SSC came not to be in our timeline. The book is called Einstein's Bridge and is by John Cramer. I haven't read it myself, but Cramer's earlier book Twistor is pretty nifty. I suggest it for anyone who might be interested in what happened to our SSC - Cramer takes a lot of the factual happenings from that time period (1987-1997) and folds it into his storyline, giving a flavor of what happens when politics and high-energy physics collide...

Matrix clip in ASCII.

Measurement, Modeling, and Analysis of a Peer-to-Peer File-Sharing Workload at http://www.cs.washington.edu/homes/gribble/papers/ p118-gummadi.pdf

and

An Analysis of Internet Content Delivery Systems at http://www.cs.washington.edu/homes/gribble/papers/ p2p_osdi.pdf

Measurement, Modeling, and Analysis of a Peer-to-Peer File-Sharing Workload at http://www.cs.washington.edu/homes/gribble/papers/ p118-gummadi.pdf

and

An Analysis of Internet Content Delivery Systems at http://www.cs.washington.edu/homes/gribble/papers/ p2p_osdi.pdf

There is error detection/correction code on audio CDs (for details see this page, for example) and PC CD drives are able to access the "raw" data on the CD, ie you can get all the stuff with error detection/correction data and you can compute if there's an error. And while it is possible that an error goes undetected despite all this, it is extremely unlikely.

Maybe not. But, I have an idea of how good it should be, and we're not there. Don't take offense if it seems to me that you have no idea how bad we have it from just a few short years ago.

Until you've seen the face of a person terrified at the idea of meeting any police, or a person shaking after getting a ticket, or a person afraid to talk to anyone in government, then you should talk.

I can guess by your lack of experience that you're without a permanent tan and haven't been pulled out of line by airport security for having one. Not through any fault of yours, as we are all birthed in our skin by chance. I would submit that freedom isn't a state of being, but a continuous struggle against those who hypocritically only value their own rights while disregarding yours. Freedom isn't very anything. It simply is or isn't happening. It can start or it can stop. The freedom to access a lawyer when your arrest has been categorized as a "terrorist action" has stopped.

We are free. We are very free. You can walk up to the White House and picket it. You can drive your truck with a rifle in the back. You can say what you want on the Internet. You can read the books you want.

Anyone can do any of the things you've mentioned and more. It is simply a matter of the consequences that becomes the deterence to those activities. Even expressing yourself on the internet can be a dangerous proposition. To keep this reply short and educational, I'll simply point you to a source you can learn from.

Even if another terrorist attack occurs, do you think they're going to take these liberties away? No. The government won't. In fact, they can't. Because people like myself speak up and let people like you know what is going on.

You're statement has a naivete that is almost charming. On the other hand, it is also a sad indictment of our public schools' failure to teach history in any meaningful manner. This failure is one the reasons why historical events repeat themselves in such tight, short cycles in the U.S., which is reflected so heavily in our foreign policies.

Our founding fathers knew what they were doing a hell of a lot better than you give them credit for.

I give them all the credit. Many of them are my heroes. Unfortunately, they are dead. The dead cannot defend their dreams. Its up to you and me to defend them at home, so that bad things don't happen to other people.

= 9J =

Dick Seymour, the longtime UW Nuclear Physics Labs computer guy, asks that I direct folks to a new URL for the Big Bang sound: http://faculty.washington.edu/jcramer/av/BigBangSo und_2.wav.

Check out the Transactional Interpetation of Quantum Mechanics. Critiques of all the well known interpretations (CI, MWI) and others you may not have heard of.

What is amazing is that Prof. Cramer used only a 16 line Mathematica notebook to produce his simulation of the "sound of the Big Bang. This summary gives you more details on his work and his writings. You also can read his column, "BOOMERanG and the Sound of the Big Bang," It has been published in January 2001 and amended in September 2003.

According to the 1.10 info here, they say you should be ready to 'save and exit' quickly.

I'm betting on all monsters turning into MSLEBs or something. Whatever it is, it will probably piss off their userbase.

I didn't see anything specific to single player, but I wonder if they are butchering SP runewords or limiting certain drops/enhancements to battle.net only. Assuming that I even play D2 again, I think I will stick to the Santuary mod (AKA 3Wave).

On the other hand, this has interesting implications for the physics of star trek weapons technology. No phasers at warp drive, and firing, never mind aiming, photon torpedoes could be a royal pain.

The main web pages, run by Computing & Communications certainly do follow set standards. However, the site from the article is hosted on the Department of Oceanograpy's own server, and they are free to do as they see fit. Surely you agree that web standards are not one-size-fits-all. But hey, I see that your website hasn't been updated in 18 months, so maybe web design isn't so hot these days anyway.

The main web pages, run by Computing & Communications certainly do follow set standards. However, the site from the article is hosted on the Department of Oceanograpy's own server, and they are free to do as they see fit. Surely you agree that web standards are not one-size-fits-all. But hey, I see that your website hasn't been updated in 18 months, so maybe web design isn't so hot these days anyway.

The main web pages, run by Computing & Communications certainly do follow set standards. However, the site from the article is hosted on the Department of Oceanograpy's own server, and they are free to do as they see fit. Surely you agree that web standards are not one-size-fits-all. But hey, I see that your website hasn't been updated in 18 months, so maybe web design isn't so hot these days anyway.

The main web pages, run by Computing & Communications certainly do follow set standards. However, the site from the article is hosted on the Department of Oceanograpy's own server, and they are free to do as they see fit. Surely you agree that web standards are not one-size-fits-all. But hey, I see that your website hasn't been updated in 18 months, so maybe web design isn't so hot these days anyway.

I wish that was the case. I attend the University of Washington, and am in their computer science program. They have just transitioned their entire department to Java. Yes, they do teach general concepts, but most of your time is wasted making "cute little interfaces" in Swing/Java2D. In a perfect computer science class, the implementation language wouldn't matter as long the algorithm you wanted to implement was implementable. I am planning on writing some letters to the UW computer science department telling them that this was a bad idea. Languages like Java, although they show the OOP paradigm, are so high level that they do not lead to a good understanding of things. The TA for my computer science class, wasn't sure if things were passed by value or reference in Java. That is partially her fault, but also her education's fault for choosing a language that lends itself to not understanding what is going on. Another thing I dislike about college computer science is that everything operates under the implicit assumtion that OOP is the paradigm to end all paradigms, and that there is not a better way to solve a problem than with objects. But, back to the point. Most Universities, assuming from my experience at UW, waste a lot of time on the cruft of Java or other high level languages to make GUI's and displays for algorithms that are generally simple and understandable.

So many studies are done about consumer behavior and advertisers' tactics and, yet, consumers behave exactly as they did before. For example, research by Elizabeth Loftus at UCI has shown that advertisers like Disney routinely implant memories into us. In one of her studies, subjects even believes that they had seen Bugs Bunny at Disneyland. Even after this was widely reported by the media, Disney ads have stayed the same and are still as likely to "fall prey" to them.

Obviously, the benefits to advertisers and consumers are quite asymmetrical from all this research. Advertisers can actually refine their techniques and perhaps learn new ones. Consumers, on the other hand, may be a little more educated but they certainly are more easily seduced. While this is not absolutely bad and may even be good in some ways, the fact remains that with increasingly power research tools like fMRI mentioned here, the potential for corporations to absolutely manipulate us increases. I'm sure that things will work out in the future, as they have always done. However, research into "defenses" against memory implantation, et al does need to be conducted.

The Research Channel, University of California, The University of Washington channel, HealthTV, University House, Educating Everyone.

The Research Channel in particular has some great lectures, and is available for free on Galaxy 10 Ku band with a 1 meter dish.

I'd like more, though, and if Cosmos Studios gets behind it, perhaps they will retransmit the Cosmos series for all to see.

> SMT allows one thread to do a bit of processing for a while, until it runs out of data. It requests data from memory and then goes off to lala-land for a little while while the other thread takes over.

I believe that's a bit off. Multiple threads will excute simultaneously, not take turns (hence, the 'S' in SMT). The point of SMT is to keep your pipe stages full, and the reasoning is that a single thread won't have enough instruction level parallelism to do that at all times. If I remember correctly, the now-defunct Alpha EV8 (21464) was supposed to be 4-way SMT. The Pentium 4 (aka HyperThreading) is 2-way. To execute two separate threads concurrently, you'll have to have two program counters.

The one thing to note about the P4's HyperThreading is that (AFAIK) the OS sees two logical processors, not one SMT processor. The significance of that is that you could actually have two separate processes run simultaneously on the CPU (as opposed to two threads of a process). My theory on why some benchmarks perform worse with HyperThreading enabled is because multiple processes will cause TLB thrashing. This is why you're more likely to get better performance from a dual core CPU.

Unfortunately, I haven't done too much reading into SMT. If you want more info, you can go here.

> Memory bandwidth has gone up by a factor of about 64, but latency has only decreased by a factor of about 10 or less.

DRAM vendors have been focusing on capacity and manufacturing costs over speed. DRAM is a commodity part, driven more by yields and manufacturing than design (not saying that design isn't important). One reason latency hasn't improved is because every bit on a DRAM cell is stored in a capacitor. Not only do capacitors leak (so you have to refresh every so often), but capacitance itself means that voltage swings will be slow. The speed gap between DRAMs and processors will get worse unless industry moves to a different storage mechanism.

I went to a U Washington CSE collqium given by a guy from Google. Their clusters have such a heat issue that they can't keep the racks next to each other. Somebody asks why they didn't use Transmeta CPUs. I beleive the guy's response was that, even taking into account the additional space and cooling requirements, Pentium-based systems still cost less than Transmeta-based systems.

This talk may be online...ah yes, here (search for "Google") it is:

Urs Hoelzle (Google)
The Google Linux Cluster
Windows Media Archive
Real Media Archive
November 5, 2002, Colloquium

I went to a U Washington CSE collqium given by a guy from Google. Their clusters have such a heat issue that they can't keep the racks next to each other. Somebody asks why they didn't use Transmeta CPUs. I beleive the guy's response was that, even taking into account the additional space and cooling requirements, Pentium-based systems still cost less than Transmeta-based systems.

This talk may be online...ah yes, here (search for "Google") it is:

Urs Hoelzle (Google)
The Google Linux Cluster
Windows Media Archive
Real Media Archive
November 5, 2002, Colloquium

I went to a U Washington CSE collqium given by a guy from Google. Their clusters have such a heat issue that they can't keep the racks next to each other. Somebody asks why they didn't use Transmeta CPUs. I beleive the guy's response was that, even taking into account the additional space and cooling requirements, Pentium-based systems still cost less than Transmeta-based systems.

This talk may be online...ah yes, here (search for "Google") it is:

Urs Hoelzle (Google)
The Google Linux Cluster
Windows Media Archive
Real Media Archive
November 5, 2002, Colloquium

Is this guy the UberGeek or what? Sahr Bio