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Friday, December 31, 2004

Another Sisyphus Job



In this entry I was talking about the mechanics of why multitaskers don't do things faster, nor that they seem to do things better. This interesting article seem to be saying the same. On top of the parallel computing idea that in order to multitask you need to constantly switch between different tasks, you also need to reinitialize your RAM everytime (by no means a simple process), it seems that humans are not efficient at constantly switching their RAMs. In other words, the constant RAM loading process seems less efficient as the day go by. Knowing that we seem to learn things after having been exposed to it only if we let six to eight hours to the brain to sleep on it, it would seem that most of us are condemned to relearn the same thing everyday...

It's not 'sixth sense' if it's smell

It looks like most animals were not affected by the Tsunami as evidenced in this story. Is this urban legend or just that our sense of smell is not good enough compared to other species. Remarkably, if birds are also able to sense this phenomena, it maybe a magnetic detection capability rather than smell.

Tuesday, December 28, 2004

Treacherous Solitons

If you think that it is just enough to think you have a warning system then you should probably think twice. In fact, it looks like, we really have no warning system in the Atlantic Ocean where a recent research paper show that a larger Tsunami to the one that hit South Asia could occur
and devastate the U.S. eastern sea shore, part of Europe, South America and Africa.

But be reassured some people tell us that no such mega tsunami can exist, well.... until something like MN4 hit us.
As expected, the internet that was supposed to survive in a nuclear war as a means of communication is doing so as seen in this E-mail sent from one of the worst hit part of Indonesia. It also seems to be a good idea to have a GSM phone when traveling.

Friday, December 24, 2004

Merci la Pologne

Vous pouvez les remercier ici, ma traduction francaise est:

Je sousigne veut exprimer mes plus sinceres remerciements au gouvernement de Pologne pour leur action qui a permit d'enlever la directive sur les brevets se rapportant aux programmes d'ordinateurs (Software Patent Directive) de l'agenda de la reunion du Conseil de l'Agriculture le 21 Decembre 2004. Il aurait ete tres dommageable pour l'Union Europeenne d'adopte ce texte.


Merci

Thursday, December 23, 2004

Metallic Parachutes

No I do not mean to talk about the Golden parachutes at Merck or DoubleClick. Rather, I am refering to this story on CNN about how a small company called BRS is designing parachutes to save crashing planes. Technology Review on the other hand tells us about a company using Nanotechnology to develop rubber tires into having more metalic properties. And while both of them receive funding from the government, you'd think that matching the two technologies might actually do some good to providing parachutes for entire Jumbo jets.

Sunday, December 19, 2004

Thought compression

This week, a code of 15 lines was produced that enables a computer to run a P2P service like Kazaa. It is here. What are the lessons from this ? Well for one, it lowers the barrier to entry so that groups of friends can now set this type of system with each other. You cannot trust anybody on the internet, but at least you could trust your friends. The second point is that I believe it takes about 15 lines of written text to explain to somebody what a P2P service is. In other words, compressing the concept of P2P sharing into a thought is close to the amount of writing needed to implement it. And it takes about 60+ lines to explain in detail to a specialist what it really does. It is what makes Python a high level language.

We don't care about sleeping like babies no more. Part deux.

In a previous entry, I mentionned how bad it would be to build a business around better sleeping facilities since most people were willing to go the chemical route anyway. This article from Forbes (thanks Cable), shows that it will become actually worse that than:

For the first time, the U.S. Food and Drug Administration has approved a sleeping pill without restrictions warning doctors not to prescribe the medicine for long-term use. Lunesta, formerly referred to as Estorra, will be available in pharmacies in January. It will be marketed with a $60 million direct-to-consumer advertising campaign.


A $60 million ad campaign, uh ? What are the chances the average doctor will resist the pressure of his customers to prescribe the medicine for long-term use ? My take is: very few will. Don't worry though, if you have any apnea and your heart stops beating, you just need to have one of these defibrillators from amazon.com next to your bed and expect somebody to use it properly.

The pollution that blinds you

We already knew of the pollution induced smog, a hazy condition produced by particle pollution. We also knew of light pollution due to the atmosphere scattering of city lights and radio FM signals. It used to be that only astronomers were disturbed by this phenomena, but now the RF apectrum is so overwhelmed with new RF sources (cell phones, 802.11...) that it now has an ability to pollute the readings made by meteorology satellites who have intruments that can detect only a few frequency bands.

Friday, December 17, 2004

Thermal Shadowing


Using the Monte Carlo ray tracer of RadCAD (a package in the Thermal Desktop suite), Olivier Godard and Tejas Shah came up with this simulation. What you see is the view of the belly of the Space Shuttle as it rotates around the Earth from the international space station. The Space Shuttle orbiter has its with the payload bay looking Nadir. Above it and traveling at the same speed is the International Space Station (ISS) which shadows the Space Shuttle whenever both of them are lit by the sun. The 1354 number in the legend is the Sun's heat flux -in Watt per meter square (W/m2)- received by the Shuttle from the Sun. The blue color shows most of the ISS blocking the Sun's heat flux. In other words what you see is the shadow of the ISS on the Shuttle. We could have done it with a raytracer used for animated movie rendering but what the nice feature here is that you can obtain a similar result that is directly usable for other thermal related computations.

Thursday, December 16, 2004

The pursuit of matching employees

Google seems to try several ways to hire people they consider very good. So they tried proximity and small challenges like this billboard announcement. But in the end, they also need to refine their needs and the only way to do this efficiently seems to be the use of Adwords with the right keywords or series of keywords. Take for instance a Google search on basis pursuit. As evidenced in the lack of Google Adwords on matching pursuit, they already know one algorithm is doing better than the other.

Wednesday, December 15, 2004

Friday, December 10, 2004

Outrageous behavior

In this entry, one is told that two outsiders have been discredited as shown in a recent peer review publication. The outrageous behavior is not the fact that there is a controversy, nor the fact that mentionning somebody's occupation is clearly irrelevant when it comes to scientific discourse but rather that the authors state the following outrageous comments:

It should be noted that some falsely reported putative errors in the Mann et al.(1998) proxy data claimed by McIntyre and McKitrick (2003) are an artifact of (a) the use by these latter authors of an incorrect version of the Mann et al. (1998) proxy indicator dataset, and (b) their misunderstanding of the methodology used by Mann et al. (1998) to calculate PC series of proxy networks over progressively longer time intervals.


For argument a)

If they are using an incorrect version of the proxy indicator dataset, does it mean that this data is not freely available ? Do these people mean to say that major climate modeling issues decided on a worldwide policy level are dependent on data that are properties of some researchers ?

For argument b)

How can a methodology be misunderstood if it is clearly published in the first place? How come the algorithm used to obtained these data is not freely available ?

If treaties are being negociated with every nation on this earth, one should at least make sure that the data from which these policies are developed follow the principles of reproducible research. As Donoho and Buckheit point out when they developed the Wavelab toolbox:

An article about computational science in a scientific publication is not the scholarship itself, it is merely advertising of the scholarship. The actual scholarship is the complete software development environment and the complete setof instructions which generated the figures


The outrageous behavior is not the criticism of datasets dating back to 1998 but rather the inability for a mining industry specialist and an economist to have access to the initial data and the means of producing the data of the paper.

Now, I will not comment on the fact that neither side of the issue seem to be addressing the fact that none of them can explain HOW components found through the PCA technique are indicative of an actual physical phenomena.

Questions to ask yourself: Wine, Women and Song.

In a previous entry, I mentionned Richard's Hamming quote coming out of his obituary. I was wrong, it was extracted from a colloquium seminar at Bell Communications Research entitled "You and Your Research". The quotes have been summarized by Todd Proebstring in his talk at LL1.

Even though some of what he says seem trivial, it is nonetheless important to have it in writing. Quotes, or entire paragraphs I like include:

Knowledge and productivity are like compound interest.


That's the trouble; drive, misapplied, doesn't get you anywhere.


Darwin writes in his autobiography that he found it necessary to write down every piece of evidence which appeared to contradict his beliefs because otherwise they would disappear from his mind. When you find apparent flaws you've got to be sensitive and keep track of those things, and keep an eye out for how they can be explained or how the theory can be changed to fit them. Those are often the great contributions. Great contributions are rarely done by adding another decimal place.


Over on the other side of the dining hall was a chemistry table. I had worked with one of the fellows, Dave McCall; furthermore he was courting our secretary at the time. I went over and said, "Do you mind if I join you?" They can't say no, so I started eating with them for a while. And I started asking, "What are the important problems of your field?" And after a week or so, "What important problems are you working on?" And after some more time I came in one day and said, "If what you are doing is not important, and if you don't think it is going to lead to something important, why are you at Bell Labs working on it?" I wasn't welcomed after that; I had to find somebody else to eat with! That was in the spring.

In the fall, Dave McCall stopped me in the hall and said, "Hamming, that remark of yours got underneath my skin. I thought about it all summer, i.e. what were the important problems in my field. I haven't changed my research," he says, "but I think it was well worthwhile." And I said, "Thank you Dave," and went on. I noticed a couple of months later he was made the head of the department. I noticed the other day he was a Member of the National Academy of Engineering. I noticed he has succeeded. I have never heard the names of any of the other fellows at that table mentioned in science and scientific circles. They were unable to ask themselves, "What are the important problems in my field?"


We didn't work on (1) time travel, (2) teleportation, and (3) antigravity. They are not important problems because we do not have an attack. It's not the consequence that makes a problem important, it is that you have a reasonable attack. That is what makes a problem important. When I say that most scientists don't work on important problems, I mean it in that sense. The average scientist, so far as I can make out, spends almost all his time working on problems which he believes will not be important and he also doesn't believe that they will lead to important problems.


Most great scientists know many important problems. They have something between 10 and 20 important problems for which they are looking for an attack. And when they see a new idea come up, one hears them say "Well that bears on this problem." They drop all the other things and get after it. Now I can tell you a horror story that was told to me but I can't vouch for the truth of it. I was sitting in an airport talking to a friend of mine from Los Alamos about how it was lucky that the fission experiment occurred over in Europe when it did because that got us working on the atomic bomb here in the US. He said "No; at Berkeley we had gathered a bunch of data; we didn't get around to reducing it because we were building some more equipment, but if we had reduced that data we would have found fission." They had it in their hands and they didn't pursue it. They came in second!


You should do your job in such a fashion that others can build on top of it, so they will indeed say, "Yes, I've stood on so and so's shoulders and I saw further." The essence of science is cumulative. By changing a problem slightly you can often do great work rather than merely good work. Instead of attacking isolated problems, I made the resolution that I would never again solve an isolated problem except as characteristic of a class.


I have now come down to a topic which is very distasteful; it is not sufficient to do a job, you have to sell it. `Selling' to a scientist is an awkward thing to do. It's very ugly; you shouldn't have to do it. The world is supposed to be waiting, and when you do something great, they should rush out and welcome it. But the fact is everyone is busy with their own work. You must present it so well that they will set aside what they are doing, look at what you've done, read it, and come back and say, "Yes, that was good." I suggest that when you open a journal, as you turn the pages, you ask why you read some articles and not others. You had better write your report so when it is published in the Physical Review, or wherever else you want it, as the readers are turning the pages they won't just turn your pages but they will stop and read yours. If they don't stop and read it, you won't get credit.

There are three things you have to do in selling. You have to learn to write clearly and well so that people will read it, you must learn to give reasonably formal talks, and you also must learn to give informal talks.


Well I now come down to the topic, "Is the effort to be a great scientist worth it?" To answer this, you must ask people. When you get beyond their modesty, most people will say, "Yes, doing really first-class work, and knowing it, is as good as wine, women and song put together," or if it's a woman she says, "It is as good as wine, men and song put together." And if you look at the bosses, they tend to come back or ask for reports, trying to participate in those moments of discovery. They're always in the way. So evidently those who have done it, want to do it again. But it is a limited survey. I have never dared to go out and ask those who didn't do great work how they felt about the matter. It's a biased sample, but I still think it is worth the struggle. I think it is very definitely worth the struggle to try and do first-class work because the truth is, the value is in the struggle more than it is in the result. The struggle to make something of yourself seems to be worthwhile in itself. The success and fame are sort of dividends, in my opinion.


In summary, I claim that some of the reasons why so many people who have greatness within their grasp don't succeed are: they don't work on important problems, they don't become emotionally involved, they don't try and change what is difficult to some other situation which is easily done but is still important, and they keep giving themselves alibis why they don't. They keep saying that it is a matter of luck.

Amazing discoveries.

Sometimes you read a series of paper and you know that there is something big behind it. Here are two examples:

The first one is by Emmanuel Candes and Dave Donoho: A Surprisingly Effective Nonadaptive Representation for Objects with Edges. As Bruno Olshausen has shown, most natural images seem to be made of edges and the human eye seem to be good a detecting those. What this article says is that there is no need for our eye system to be adaptive to figure out an image. This is an impressive result because most people think otherwise.

The second series of papers by Emmanuel Candes, Justin Romberg and Terence Tao entitled Robust Uncertainty Principles: Exact Signal Reconstruction from Highly Incomplete Frequency Information and Near Optimal Signal Recovery From Random Projections: Universal Encoding Strategies? show that the right type of signal, decomposed with the right bases, can be reconstructed using an simple linear optimization algorithm. This finding is tied to ubiquitous power laws.

We still need better maps

Here is a way to deal with navigation in towns: Use cell phones as tour guides. With the ubiquity of cell phones, one can definitely think of a cell phone as replacing previous more expensive solutions.

Weather patterns influenced by wind farms

With all the talk about renewable energy not affecting the environment, here is one article that seems to say otherwise. Evidently, it would be easier to go after the real polluters than the ones directly warming the atmosphere, right ?

Wednesday, December 08, 2004

Tuesday, December 07, 2004

Interesting way of teaching

Via Lemonodor, here is a very funny but effective way to learn some LISP through comics.

Sunday, November 28, 2004

Better be deaf than hear this, it seems.

When the first results of the Ukrainian election were announced on TV, the screen was split between the official anchorwoman and a little window was reserved for the person doing the sign language translation of the anchorwoman. Except, it was not translation, while the anchorwoman was saying that the Viktor Yanukovych had won the election, the sign language person was miming "Do not believe them"....

Thursday, November 25, 2004

Much ado about zipping

While the most recent news tells us that one could figure out who the original author of a painting through the quantitative evaluation of paint brushes, the mystery of who wrote Shakespeare's story is still a matter of debate. Maybe applying a technique such as the one mentionned here might help.

Monday, November 22, 2004

Halfway To Being Something

If you are nothing without your Robot car, then we are halfway after this week-end with 4WD Jeep Cherokee. Lot's of driving to find the gem but we are satisfied.

Sunday, November 21, 2004

Repelling SOME cosmic rays with magnetic bubbles

When I see something like this, my eyes roll. Ok so you have superconducting magnets that deflects electrons, ions, and so forth. But what about the deadliest of them all, neutrons, you know the ones with no CHARGE. The ones who by definition cannot be deflected by a magnetic field, arghhhh....

Saturday, November 20, 2004

Scripting in Computational Science

I found this book by searching around. This is very interesting for the scientifically orientied person who wants to switch from Fortran. For instance, he gives examples of Python vs C for GUIs or the things that you cannot do easily in Fortran nor Java can be found here and
here

Thursday, November 11, 2004

Election result maps

We all have seen the red/blue map of the U.S. right after the election. Here is a twist to it, this map changes the shape of all counties to reflect the size of the population that lives in them.

Greed or Complexity ?

When I read a journal entry like this one, I always wonder if this is a display of greed by management or just a display of the misunderstanding of the complexity of a seldomly innovative video game.

Wednesday, October 27, 2004

October surprise


On this day, the Red Sox won the world series after 86 years of unsuccessful attempts, a total Moon eclipse could be seen that night, the Huygens-Cassini probe made the closest ever picture of Titan and Iris was born.

Wednesday, October 20, 2004

Questions you have to ask yourself

At LL2, Todd Proebsting had this very insightful talk on innovation in programming languages. His first slide is about a extract of an orbituary of Hamming

Richard Hamming’s three questions for new hires at Bell Labs:
1- What are you working on?
2- What’s the most important open problem in your area?
3- Why aren’t they the same? (Ouch!)

“You and Your Research” --- Richard Hamming (1986)


The whole video of his entertaining but insightful talk is at : http://web.mit.edu/webcast/ailab/mit-ll2-s2-09nov02-80k.ram What is amazing is that his talk can be applied to so many different problems areas not related to programming languages that it really strikes a chord with me. Some of the gems:
It's Bell Labs, we hired you because of your judgement but you are obviously not using your judgement because you are not working on the most important problems in your field

I am glad to hear you're on it

Undo is hard

(map fn L) vs. while (*d++ = *s++);

It's almost never a regular expression

Parsing is too hard

On disruptive constraint solvers:
You give up, which is what I did

Prolog is fine but it does not solve other problems

Objects are fine, I am giving you a 1000 of them

Monday, October 18, 2004

Solar System Weather Report

While on Earth tornado and hurricane seasons are coming to an end they are still going strong on Mars, Jupiter and Saturn.The sun is calm today.

Thursday, October 14, 2004

Bandelets to bar code

The company LET IT WAVE is developing a technology close to Curvelets and Contourlets called Bandelets. While the JPEG 2000 standard is an improvement over the current JPEG format, the bandelets seem to be an improvement over JPEG 2000. Here is the same photo truncated to 500 bytes so the information could fit into a bar code


Pretty impressive.

Wednesday, October 13, 2004

Entering the DARPA Grand Challenge Race

After much time looking into it, we are ready to make this hobby a more serious hobby. I created a blog for our entry into the DARPA Grand Challenge race. Not much detail can be found there because with a small team, we'd rather concentrate on the most important thing, the vehicle and its autonomous driving system. Why Pegasus Bridge ? Because, on all accounts, we don't think we are building a car....

Tuesday, October 12, 2004

Peak Digit

It looks like as soon as the thriteenth bar will be implemented, we will be already full and looking to have a fourteenth. Yes, it is not justoil anymore, we now have Peak digit.

Monday, October 11, 2004

Have you ever seen a spacecraft being tested ?

Here is one: The ESA Venus Express. The reasons these guys have white gowns and hairnets is because you don't want to contaminate the spacecraft with particulate matters. Since the Venus Express is going to Venus, it is likely to feel very warm since it will be closer to the Sun during its mission. It is therefore imperative that any of the Multi-Layer Insulations cloth and other outside thermal protection materials properties do not degrade because of contamination. Any property changes of the outer layers will directly have an impact on the temperature inside the spacecraft.

A Master Builder Passed Away

Max Faget passed away this week-end. Here is a quote I like from what is being said about him:

Seeing things from a different angle was another strength, and he sometimes made dramatic demonstrations of this.


His designs included the escape pod of the Saturn V rocket (the metal tube at the front of this picture is a rocket with three small nozzles) and the wake shield facility,

Ad astra Max.

Sunday, October 10, 2004

Seven oil platforms were destroyed by Ivan

This is the type of news we've not heard about when hurricane Ivan was hitting the Gulf coast. But it looks like seven platforms were detroyed. I just added this information to wikipedia. At $52 a barril, we are approaching a perfect storm. This is noticeable because the actual effect of the destruction of these platforms on the daily consumption in the U.S. is actually very minimal.

Thursday, October 07, 2004

A-ha moment, part I


Through the course of learning, one always tries to make sense of the learning material through story-telling or through an obvious internal representation. The a-ha moment is when you realize that you now have found this internal representation... and you can't get it out of your mind. It may be triggered through an awesome graph or a simple key sentence that makes the connection between two dissimilar subjects. Recently, when I was reading the literature on on-line parameter estimation using the Unscented Kalman Filter, I was having problems making a comparison between the unscented transform and previous methods such as the Extended Kalman Filter.



Featured sideways is the graph that explained it all. Similarly, one cannot understand the slaughter of Napoleon's army  during the Russian campaign until ones contemplate this map that connects the thickness of the line with the number of surviving troops. Similar very good examples can be found in this gallery of Data Visualization.

Tuesday, October 05, 2004

Intelligent Thermal Vacuum Chambers

In this invitation to bid from ESA, they seem to have a need for a way to accelerate thermal testing. In their words,

Modern spacecraft require lightweight solar arrays capable of withstanding either at least a thousand very deep thermal cycles in Geostationary orbit (GEO), or several tens of thousands medium thermal cycles in low earth orbit, or high range temperature thermal cycles for space missions to the sun vicinities (e.g. Bepi Colombo, SOLO, etc.). Extensive tests on solar array samples have to be performed in order to ensure that mission requirements will be met. The objective of the activity is to procure an accelerated thermal cycling facility with the required characteristics to fully cope with the thermal cycling test conditions defined for LEO, GEO and close to the sun missions, with the additional ability of performing short duration cycles, so the testing time for qualification and evaluation programmes can be considerably reduced.

Maybe a way to do this is through better analysis while the testing is being performed ? Maybe an idea would be to allow for the chamber to be intelligent about the actual thermal cycle the payload has to go through ? Imagine that, Intelligent Thermal Vacuum Chambers ...

How can a 32,000 lb truck be stopped by a bush ?

Just make it driverless. A more accurate analysis can be found in this document relating Terramax's entry into DARPA grand challenge of last year.

Nice little exercise to go from sensor reading to a GUI

The nice thing about python is the quick prototyping capability to do this sort of thing.

NOAA-N-Prime Satellite Mishap Investigation Report Released

The NOAA-N-Prime satellite mishap investigation report has been released. This is a follow-up of this entry. Please note the following in the report:

Errors were made by other team members, who were narrowly focused on their individual tasks and did not notice or consider the state of hardware or the operation outside of those tasks
(Page 9.)


In my view, the conclusion of the report points to one thing, no matter how many "Q/A" people you have on-board, if the organizational structure is not working, then you cannot expect a Quality Band aid program to help in anyway.


Monday, October 04, 2004

The September issue of "La Lettre de la SCM" just came out.

La Lettre de la SCM just came out

In "Eoliennes", there is a mention of wind turbine failures given as a very low probability by experts when, in fact in the course of four months, two have been destroyed (because of the wind!) What is fascinating is that with the increase in power ratings of wind turbines, we are likely to see these probabilities even go up. Indeed, three hundred of these turbines could replace one nuclear power plant. This is not to say that electricity would be cheaper (currently the wind power industry is subsidized by the government) nor that it would help France in fulfilling Kyoto's treaty CO2 levels promises since both energy sources do not produce any.

"La théorie n'est pas au point" mirrors my previous comment on orders of magnitude in the prediction business when it comes to the environment.

In "Identification", there is a mention made of the fiasco in using biometrics issues when it comes to identifying people and that smell may actually be a better classifier than face recognition. This is a good idea, as it stands, dog smell is already looked at to detect some cancers. Smell might actually be a better detector of intent than the currently flawed idea that databases are going to protect us. As a traveler, do I care more about a seating next to

1) a serial killer or,
2) a bomb ridden "peaceful" person ?

The database says 1. I say 2. In a related news, Smell study has netted some researchers the Nobel prize today.


The rest of this september issue of the SCM Letter is a very good and entertaining read (if you read french that is.)

Wednesday, September 29, 2004

The New MacArthur Geniuses are in.

I was intrigued when I first saw this new announcement of the MacArthur fellows winners. So I did some digging and found this article written in 2000 in Slate: The MacArthur Geniuses - How to become one of them. By David Plotz. What is fascinating is that one can see how the winner's prototype description back in 2000 follows nearly word by word the description of some of the 2004 fellows. Tunnel vision anyone ?

Watching a volcano erupt

With the new volcano advisory, one can now watch the Mount St. Helens Volcano erupts from your own living room.

Yes....one more to go

The first attempt by SpaceShipOne was successful. One more to go to win the Ansari X-prize. Our friends at Ecliptic provided a video of the event. Virgin Galactic will provide rides on this bird later at the tune of $200,000. This is about 4 minutes of zero-g for $200 K and the disctintion that you can now be called an astronaut. For about a hundred times less you can spend comparable amount of time in zero-g in a parabolic flight in a plane but no astronaut title.

MREMS: Micro-Radioisotopic-Electro-Mechanical Systems

This feature article of IEEE spectrum does a good job mentionning the issue of radioactive microbatteries that could power future MEMS.

My own preference is for Polonium-210 which has the ability to release about 120 W per grams. This is huge. Unfortunately, as said in the article:

At the diminutive dimensions of MEMS devices, the ratio between an object's surface and its volume gets very high. This relatively large surface makes it difficult to sufficiently reduce heat losses and maintain the temperatures necessary for RTGs to work. So we had to find other ways of converting nuclear into electric energy.


For a sphere, surface area decreases as the square of the radius whereas its volumes decreases as the cube of the radius. Hence, as the size decreases, the surface area become more important for the volume: i.e. major heat loss is expected from this sphere. Realizing this, Tom Blanchard from Wisconsin-Madison decided to look at this through the building a micro heat barrier. Hopefully, we will be able to keep high temperatures in that sphere so that thermoelectric generators can be used. It is also wrong to think that NASA has been looking at only Plutonium as an RTG sources. Back in the 1960's Strontium was looked into as a source of power for autonmous buoy at sea. Even polonium was looked at but the mission scenario requiring this type of sources with a half life of 138 days were non-existent. I recall the preliminary design needing a lot of shielding and being heavy. But then again, if the only issue is about having polonium not surrounded by a thermally conductive material, what about using aerogel instead ?

Tuesday, September 28, 2004

See it from the ground, see it from the sky. Part II

After the moon tracks of the Apollo 17 mission rover, here are the different views from the ground and from the sky of the Mars of the tracks of the MER-A robot (Spirit). If we can see the lander and the chute, does it mean we can better see Beagle-2 or the Mars Polar Lander ?

Local Weather Prediction for the People III

As I mentionned in a previous entry, here is a service that is developing itself in order to provide better weather information: ForecastWatch -- The Weather Forecast Accuracy Authority.

Monday, September 27, 2004

Airport Terminals Collapse

There is an eerie feeling that the Dubai airport terminal collapse looks too familiar to the Paris Terminal collapse. In fact they both have the same architect whose recent project include the following terminals:


Dubaï, Terminal 3

Charles de Gaulle, Terminal 2 E,


The commission that looked into the first collapse in Paris seemed to say that the sudden collapse is linked to the perforation of the concrete roof by the struts (supporting it). The science of concrete is a very difficult one, especially when it comes to computing its performance in an inventive type of architecture. Hopefully these accidents will be studied very carefully so we can have an answer like we did for the sleipner platform collapse which also included concrete walls.

On a related note, I think I understand how people get to be chosen in order to bid on contracts like these and I can see how a certain amount of ego goes into the decision making process. But, I do not understand how little emphasis there is on the functionality of these airports. When I fly out of Charles de Gaulle, I certainly do not expect the nice design of the buildings to give me a more interesting flight experience. I would rather that they put an emphasis on, the following:
  • Is security good ?
  • How cheap is the airfare ?
  • Can I get for free on one of these airlines clubs ?
  • Do I have an internet connection in these clubs ?
  • Can I board first ?
When I land in Paris, I look at the following:
  • Can I get out of the plane first ?
  • Can I get to customs without having to ask people where to go ?
  • Can I get through customs without having to wait for an hour (because they are all at lunch) ?
  • Can I get my luggage fast ?
  • Can I find some ATM machine fast ?
  • Can I quickly find a Taxi or a shuttle bus ?

Most of these items do not need the airport buildings to look good. Most airports including CDG fail at providing a decent solution to these expectations.

Sunday, September 26, 2004

Perfect Storms

One can only wonder if the collision of several seemingly unrelated facts is the precursor to a perfect weather/financial storm. Take for example, the oil price going up because of the, now, fourth hurricane hitting the Gulf of Mexico and Florida and the increase in foreclosures in Houston because of a hot summer (actually not the hottest one in the past five years.) Knowing that the weather is getting drier/warmer in Texas when there is a hurricance in Louisiana/Mississippi like it happened two weeks ago with Frances.....

Friday, September 24, 2004

Local Weather Prediction for the People II

In today's previous entry I mentionned that there seems to be small markets that are pretty much untouched for weather predictions since the brunt of previous and current efforts have been focused on very hard to solve problems such as predicting Jeanne's tortuous path or figuring out why in Europe, August 10-12th is a period of strange weather patterns like in 2002 or 2003 or trying to figure out if one should evacuate New Orleans or Miami. They have such tremendous economic value that the trade-off of investing in tools to predict them is seen as worthy by governments. But aside from these very weird events, minimal variations in the weather patterns over short distances (less than the coarse grid designed for supercomputer input) are now becoming important enough that it affects events with attendant economic value. I will try to mention these in a future entry.

Nuit Blanche Paris 2004

Folks, there is nothing here to see on the subject on this blog. Please go to this "hidden" Nuit Blanche web site instead. It will take place on October 2nd, 2004. Have Fun!

Non, ceci n'est pas le site de la Nuit Blanche de Paris, veuillez plutot aller vers ce site "cache" (il n'y a pas de lien direct avec address http depuis www.paris.fr ) de la Nuit Blanche. Cela le se passe le 2 Octobre 2004. Amusez-vous bien!

Local Weather Prediction for the People

There is a segment of the population that needs to have accurate weather prediction on a specific day or have access to specific historical data and they are willing to pay for it. Case in point, the prediction of wind patterns for wind turbines. In France, one is beginning to see micro-local weather prediction services such as Meteoconsult or Meteopartner that are dedicated to serve micro-markets such as bread makers who need humidity data to see if they should prepare their flour on a specific day. The interesting part of this story is that they can do this because most of the supercomputer time spent on devising the weather for the world is spent here in the U.S. and freely available on the net. Meteo France is screaming that it is unfair competition that a small companies like Meteopartner can have acccess to data like this because they did not really pay for it unlike them. The other interesting part of the story is that the niche market found by these smaller outfits is precisely the type of customer that could not be a customer for large outifts like meteo france. There is a need to dedicate special numerical skills to interpolate weather data from the current and too coarse data coming out of supercomputers (20 kms by 20 kms grids.) If the smaller outfits are capable of finding enough customers, they are very likely to be the big dogs in the future because this is clearly a scenario described many times of Disruptive Technologies. Maybe learning how to solve the Navier-Stokes equation was not such a bad skill after all....

Wednesday, September 22, 2004

If ALICE is not even a teen-ager, how do you expect a robot to drive 150 miles alone in the desert?

According to slashdot, ALICE Wins Loebner Prize 2004. It actually won the Bronze medal only. If Artificial Intelligence is at this stage of the game, how come people expect to win the DARPA Grand Challenge race ? Maybe it's because they don't think it is Artificial Intelligence in the first place ?

Tuesday, September 21, 2004

Weapons plutonium disposition will take place

It looks like after years of thinking about it, part of the U.S. Weapons plutonium stockpile will be initially processed in France. This is good news because it reduces the danger of proliferation of this material in the future. What annoys me in these types of articles is the assymmetry of experts and stories. The anti-nukes side is always overepresented because the pro-nukes are generally the people who are working in that field and they generally work for the government. For instance, in this article, when Tom Clements says that

It is the height of arrogance to carry out a shipment like this while demanding that other nations refrain from proliferating nuclear weapons’ materials and technologies

he basically shows a lack of knowledge of what proliferation means. When you ship special nuclear materials (SNM) from a nuclear weapons state to another nuclear weapons state, you do not proliferate. But then again what would you expect from a spokesperson from Greenpeace international. When Edwin Lyman, from the Union of Concerned Scientists in Washington DC states that
the undertaking is ill-conceived, poorly executed and inadequately secured.

I would like to know if he knows something that everybody else does not. How ill-conceived is a plan that is the final solution to a process that has lasted at least eight years and lived through two different administrations of opposite end on the political spectrum. When he says
It would be safer to choose the “plutonium immobilisation” option

Mr. Lyman does not tell the other side of the story: i.e. that the reason this solution to plutonium disposition is chosen is because it is the mirror process that involves the Russians. See, the Russians have double the amount of weapons plutonium and will not ever think of plutonium as trash. They put a lot of lives/money/effort in producing it, it is a national treasure to them. The response from guys like Mr. Lyman looks like the lessons given by the super rich to the poor, some sort of a nuclear equivalent to "let them eat cake." The Russians always told the U.S. that immobilization amounted to storage. Storage means that plutonium can be retrieved "easily." This situation is unacceptable to both parties eventually because it would mean that it is not disarmament. The situation is even hilarious if it were not for this serious subject. When Mr. Lyman talks about the immobilization option by mixing
manageable plutonium with highly radioactive waste – making it hugely dangerous to anyone attempting to misuse it – before encasing it in glass and disposing of it.

It is the type of thinking of another age; before 9/11 to be exact. Before 9/11, nobody thought that people would hijack a plane and ram it into buildings. The same goes for this "immobilization disposition" solution: to think that nobody would get this glass casing, blow it up, pick up the pieces and try to assemble a weapon out of it is a sure sign that the Union of Concerned Scientists has not evolved since 9/11. The tragedies of 9/11 or Beslan tells us that you will find people who will do this and die doing it (because of radiation exposure) but will eventually get that job done. Matt Bunn, whom I respect, underestimates the French when it comes to nuclear issues. France has 50 nuclear power plants and a mature fuel recycling program, the U.S. has 100 nuclear power plants and stores all their waste at every plant, who is more vulnerable, Matt?

We don't care about sleeping like babies no more

In a previous entry, I was making a mention of an italian study on sleep. This new study from SleepApneaInfo.com shows that Americans downplay sleep as crucial to health

Although they admit that a lack of sleep affects their work and sex lives, the majority of Americans don't believe that sleep is an important factor in maintaining good health, a new poll finds.

The survey of 2,442 Americans, conducted by SleepApneaInfo.Com., which is run by companies that make sleep disorder therapies, said that 62 percent of Americans thought that diet and exercise were more important than sleep in staying healthy and happy. Seven percent said none of the three was important.

According to the survey results, 58 percent of employed American experienced some daytime sleepiness, while 39 percent said that they don't have sex because they're too tired.

About 40 million Americans suffer from sleep disorders, and 18 million of them have obstructive sleep apnea, in which the person stops sleeping many times a night because of a blocked airway.


With this type of results, one wonders how the sleeping industry could awake...

Monday, September 20, 2004

Lessons learned for asteroids and earthquake will eventually converge

Will a 5.5 earthquake in southern california that was 14 days late be considered a success by the Keilis-Borok team ? Please note that the miss of the Assissi earthquake is symmetrical to this southern california miss. The M8 algorithm said the Assissi would be 5.5 and ended up being 6.5 whereas this one was predicted to be 6+ and ended up being late and less than expected. What is seriously missing in these stories is the idea of probability distribution, there is no way the M8 algorithm said there was no chance whatsoever of a quake after September 5th if it had not occured by then. At one point or another, like the controversy that erupted for near earth miss of asteroids, this incident will lead the scientific community to be more behaved when it comes to warning the general public.

Modelling Criminality

Modelling criminality in the urban environment seems to be a new area of scientific investigation; the title "crime mapping as anticipation" reminds me of a recent movie.

How should we evacuate New Orleans ?

You'd think that evacuation of a town like New Orleans is something that is well understood for no other reason that its clear exposure to the elements. Well it seems that it is not really. What I do not understand is how can the federal government invest money in evaluating traffic jams in Dallas or Portland but not in the evacuation of a major city like New Orleans.

Thursday, September 16, 2004

Google's playground

Google Labs is an interesting place where they seem to test their new products. A good way to do rapid prototyping.

Number Theory can even get you a job !

It is a stunning news indeed. Besides putting observatories at the right locations, number theory can also get you a job at Google. The fascinating thing, is that most researchers in Number theory would agree it is not challenging when it can be found easily.

GPU programming VI

While reading GPU Gems, I found the article I really wanted to see: How do you go from a numerical analysis background to programming with a graphics card. How do you map what you already know into something that a chip does well. Well Mark Harris explains how you solve the Navier Stokes equation on a GPU. That's enough for me to do the rest of the mapping I think.

Tuesday, September 14, 2004

Vortices and Spacecrafts

Am I the only one to make a parallel between this movie and this picture.

Spilling your guts for only $3,000

Cable just sent me this MSNBC article on Zero-gravity flights going mainstream. It has been a long time in the making and knowing some of the people involved I can only say it took some stamina. The idea of allowing the plane to be used as cargo was one of the few ways one could make this whole operation work because otherwise the economics is not very good (I checked some years ago.)

In the meantime, checking the survey from the MSNBC site reveals that out of 4200 people only 11 % would not go or are indifferent, 33 % would like to know where to sign up and 56 % thinks it is fun but too pricey. As having done it several times, I can only say that I surely would have paid that much to do it once. One of the very interesting aspect of these flights is that even though you are "having fun" for two hours and half. The experience is so novel to your brain, that it feels like you spent only fifteen minutes in the plane, so you really need to bring your camera.....

Should New Orleans be evacuated ? ( Doit-on evacuer la Nouvelle Orleans ?)


According to most computer models , Ivan
will hit New Orleans. New Orleans has the specificity of being 15 feet beloww sea level. Is this the big ONE ? Check how high the water level will get in the French Quarter.
. A similar question was asked earlier.

Monday, September 13, 2004

11 Empty Quivers

I never realized that there were that many. If no other reasons than making sure they are not going to detonate, it would seem to me that addtional manpower should be put to find them in order to potentially improve dramatically the stockpile stewardship program.

Interesting numerical links of the week

A toolbox to do interval arithmetics: INTLAB - INTerval LABoratory Ver. 5

An interesting approach to algorithm development and start-up funding: Fang Inc. with interpolation schemes

Two books from C.T. Kelley of North Carolina now freely available on the web from SIAM: Iterative Methods for Linear and Nonlinear Equations and Iterative Methods for Optimization

A free non-equispaced fourier transform package at:
http://www.math.mu-luebeck.de/potts/nfft/

Eric Brochu, Nando de Freitas and Kejie Bao just made available this paper: Owed to a Martingale: A Fast Bayesian On-Line EM Algorithm for Multinomial Models . UBC CS Technical Report TR-2004-08.

and finally an MPEG-4 encoding library for the people: Revel

Exoplanet detection using number theory

This approach by Daniel Rouan to nulling interferometry as used for the detection of exoplanets uses number theory to define the location of the spacecraft-observatories. This is fascinating.

Saturday, September 11, 2004

The Davalos-Carron's Law seems to be holding.

The Davalos-Carron's Law states that the size of the text in all of one's Email stack is exactly a thousands times less than the size of the all its related file attachments (jpg, mpg, pdf,......) We currently have in our collaborative project system something like 12 MB of text for the different "E-mail" exchanges we have with each other (threads), but the size of the library associated with this application which hold all the attachments associated with these threads is now 12 GB.

GPU programming Part V

It looks like Google has difficulty making a difference between a good link to programming a GPU and one that only relates specific examples like my blog on the subject. My blog is on the first page of Google for the expression "GPU programming". It shouldn't.

Friday, September 10, 2004

They do lightnings but they don't do tornadoes

Second email of this kind today, after the rabid bats, here is the lightning warning. Now what I want to know is what to do when a tornado hits since it is more likely to hit this region than lightning. It looks like I am not the only one concerned about this issue.

Safety Issues - Take Lightning Hazards Seriously


Lightning is one of nature's leading causes of injuries and deaths each year in the United States. To alert students, faculty and staff of these hazards, lightning warning systems have been installed on the Texas A&M campus and at numerous parks and schools in College Station. When the likelihood of a cloud-to-ground lightning strike is high, these systems will sound one long 15-second blast from the horns. Intermittently flashing lights or strobes will continue for the duration of the hazard. Three 5-second blasts signal that the danger has passed and normal outdoor activities can resume. These systems are used solely to warn of lightning hazards.


If you hear the danger signal, you should find shelter quickly since the storms that produce the lighting typically arrive within minutes of the alarm. Organized outdoor activities should be suspended until the system gives the "all-clear."


When lightning hazards are present, avoid tall trees, flagpoles and high open areas. Golf carts do not offer the same protection as automobiles. Know the signals and protect yourself. ...

Are rabid bats beneficial ?

Just got this in my E-mail stack:

COLLEGE STATION: A reminder to avoid contact with bats is being made by Texas A&M University officials. The annual bat migration may be starting earlier that usual this year, perhaps due to milder than usual temperatures in August and September. Due to the expected increase in the number of bats arriving in this area during the annual fall migration, officials want to caution individuals about handling or approaching bats.

According to Dr. John Patton, a Research Scientist with Wildlife and Fisheries Sciences at Texas A&M University, only a small percentage of bats will have rabies. Although rabies can only be confirmed by a laboratory, any bat that is active during the day, is found in a place where they are not usually seen, or is unable to fly is far more likely to be rabid. These bats are often the most easily approached, and should not be handled.

Bats commonly found on campus are Mexican Free-tailed bats which have been named the Official State Flying Mammal of Texas. For this reason, universities and other entities that have to deal with bats are limited in ways to control them. When bats must be captured and removed from campus, they are transported to a remote area and released. In fact, bats perform a very beneficial service because they devour large numbers of insects.

Anyone on campus encountering a bat that is on the ground or otherwise acting in an unusual manner is requested to call Pest Management at....


So, if you see a rabid bat coming at you, you can't "take care" of it. uh....Only in Texas.

GPU programming IV

While it looked like the speed up was up to ten times, it looks like for solving specific equations, the speed up is only 4 to 5 times as fast. Good enough for me.

Wednesday, September 08, 2004

Why would one jump out of a perfectly working airplane ?

Both the Genesis probe and Beagle 2 did not open their chute properly and crashed. Unlike Beagle 2, Genesis is likely to still be a live ordinance.

Tuesday, September 07, 2004

Hypertaskers don't do things faster

In this article, people seem to say that hypertaskers do things faster but not better. I would not be so sure about that. When you read the convincing argument of Joel on multitasking and parallel processing (which seems to be the process identified in the Harvard study), you realize that for tasks that are supposed to last about equal time, you will not do things faster for any of the two tasks.

Nature: 4, Human Modeling: 0

  • Sharp downgrading of Frances before it hit the Floridian shores.
    Nature 1, Human Modeling: 0

  • Charley's sharp turn
    Nature: 2, Human modeling: 0

  • On Sunday, there was no 6.4 Earthquake in Southern California
    Nature: 3, Human Modeling: 0

  • But it ocurred in Japan instead
    Nature: 4, Human Modeling: 0
  • Monday, September 06, 2004

    The Columbia hit the foam, not the contrary.

    I was watching yesterday a show that looked like it was a NOVA program on the Columbia flight. What stroke me was that everybody was in denial and could not believe a foam piece could have done that much damage. However, a simple back of the envelope calculation using the high speed imagery of the take-off shows that the foam piece is being overtaken by the shuttle at a speed of 924 fps or about 1060 km/hr.

    Sunday, September 05, 2004

    Tex-MEMS VI is on

    The dreadful aspect of organizing a meeting like this is that you eventually seldom enjoy it. By that I mean you don't really get to see the good presentations or at least the ones you want because there is always something for the organizers to do. Case in point, I still don't have a title for my presentation yet, with the meeting on thursday, this is not good. At least being an organizer allows one to have a place holder. Most abstracts can be found here.

    Saturday, September 04, 2004

    Nice toy

    I was at the toy store today and found the following RC car. Not only does it do the RC car thing, but it also has a little camera (a CMOS) in the car that transmits video to the RC console.

    Friday, September 03, 2004

    GPU Programming III

    As a result of using GPU instead of the main CPU, it looks like we can go from 5 Gflops on a CPU to 50 GFlops on a GPU. Time to hone some skills.

    Frances from different altitudes

    From the International Space Station at 300 kms:1, 2, 3.

    From TRMM at 403 kms: 1

    From SeaWifs at 705 kms: 1,, 2, 3, 4.

    From the GOES satellite at 36,000 kms:1

    Wednesday, September 01, 2004

    Online parameter estimation for space related thermal problems

    We are going to present a paper at TFAWS 2004. The abstract is here. The idea is eventually to be able to do model estimation while we do payload qualification in the thermal vacuum environment. In general, the process involves a lot of back and forth estimation and testing to get the model right. The intent is to eventually use Particle Filtering techniques like MCMC.

    You want another type of FUD ?

    This article relates the fact that full-body CT scans pose high cancer risk. Where have these people been hiding ? Yes it is risky to take CT scans but it also absolutely far riskier to have an undetected tumor...

    Tuesday, August 31, 2004

    Alice in Warland


    This graph is very telling. A very common name like Alice shows brutal changes during WW1 and WW2.

    Transit of a transit


    This is a photo by Tomas Maruska taken during the recent Venus transit. The second object is the International Space Station. wow.

    Monday, August 30, 2004

    Reconstructing stars

    When you do interferometry, it is not uncommon to have a set of incomplete fourier component data of the image of the star you are observing. This article seems to provide a good way to do a good reconstruction which is hopefully better than the current ones (paragrah 5.2.)

    Waste is good. Nuclear waste is better.

    This article reminded of the words spoken to me by a person who made it big (professionally that is) in the area of nuclear waste processing. He mentionned to me that initially, within the French public sector, you really needed to come from the best schools in order to get the top spots except when it came to dealing with nuclear waste. Nobody would touch the subject with a ten foot pole. Years later, nuclear waste reprocessing became such a hot button because it was the only bottleneck of the nuclear power policy that he himself became a pretty important person and would have a definitive say on how the country would eventually deal with the issue.

    Desperately seeking primes II.

    So this new algorithm can figure out if a certain number is a prime in O(log(n)^6) as opposed to O(log(n)^12). So that would mean O(log(10^(10^7))^6) = O(10^(6*10^7))= a constant multiplied by a number with 6 million digits of operations instead of a constant multiplied by a number with 12 million digits of operations in order to find a prime that is worth it. Yes, that is quite an improvement.

    Tick Tock, Five more days till a 5.5 earthquake hits Southern California or a model crashes into oblivion.

    In a previous entry, I paralleled the belief that people had in earthquake modeling and spam filtering. Time is running out on this earthquake model....

    Saturday, August 28, 2004

    Like in the movie Brazil, it looks like there is a way to design an algorithm that devises human intent

    How can one determine intent algorithmitically : a profound human feature, when only juries in courts of laws can determine it ?
    Irrespective to the fact that Secure Flight seems to have its days numbered because of its inability to figure out that a Member of Congress like Ted Kennedy is not a terrorist or that there are a bunch of David Nelsons, the real question is : whoever came up with this most impressive capability needs to licence/patent it to the private sector because not even Google can make a difference between different David Nelsons. Are we getting to the point where the uneducated masses of flight attendants (they are not educated in screening people) can have access to defective databases and have a say-so on one's ability to move inside this country and do business ? Have we gotten to the point described in the movie Brazil where a squashed bug changes the life of a person by entering the wrong name of Buttle instead of Tuttle in one of these databases? Only time will tell....

    The road less traveled by an autonomous car

    When you are shopping for a vehicle that would sustain the DARPA Grand Challenge. You are thinking: maybe a pick-up truck is not enough, I need to put additionnal hardware on top of it. And then you watch these two videos. The next step of this endeavor is probably to build a radio-controlled car and try to grab some "good" advice ? I say "good" because the wise word includes a link to a library written in C++ and Java. With this type of help, how can you be expecting to beat the averages and be the best ? I am not sure.

    Damping expectations..

    In this article, Bose founders seem to be inclined to devise a new suspension system that promises to be revolutionary. When you drive with a woman that is expecting, you know that whole body vibration is indeed a concern:

    " The unknown threshold value for adverse effects on pregnancy suggests a limitation on an occupational exposure to the lowest reasonable extent. "

    that has only recently been looked into as a subject of study:

    " Recent studies have indicated that female workers who become pregnant and are exposed to WBV can possibly have added risk factors such as miscarriages and other gynecological disorders. "

    Thursday, August 26, 2004

    Plumbers in Space.

    And you thought being an astronaut was all Buck Rogers. Better be the best plumber there is if you want to get in according to this internal NASA HQ release :

    All electric current readings for the water pump with the newly installed rotor were 'as expected for a normal operating pump', both without and with water flowing through it. No leaks were found. This unprecedented level of on-orbit repair on an EMU, a pioneering feat that finally regained cooling after over a year (!), is an important milestone: Its 'lessons learned' greatly advance engineers' understanding of how these spacesuits operate after being in zero-G over extended periods, and that clearly impacts our preparation for future long duration space missions.

    Saturday, August 21, 2004

    Reduction of D2 dopamine receptors reduce cognitive functions

    it stops the brain from associating reward to visual cues associated with rewards. Hence monkeys work earlier and longer on tasks since they do not know when they are going to get rewarded. Uh....

    Should Miami be evacuated ? (Doit-on evacuer Miami ?)

    What are the chances that the sharp turn of Hurricane Charley turns out to be due to Nonnormality as seen in Generalized Stability Theory ? In a few words, many different climatic models do tend to refer to the largest eigenvalue of the linearized version of these models to make an inference on what they can predict: i.e. if the eigenvalues are all negatives, then the system is subcritical and will wither away. The problem with this assumption is that eigenvalues are only telling you something about an asymptotic behavior not a short term one. The other problem is that if you deal with the linearized version of a nonlinear system of equations (like the Navier stokes equation that governs fluid flows such as the air in a hurricane) and if nonnormality is large (it seems to be an accepted fact when dealing with fluid flow) there is a great chance that you will never have time to "live" close to the initial conditions of the system since transient growth will make your assumption on the linearization totally invalid. This is also a sign that scientists predicting hurricane paths do not seem to have understood a specific strong coupling between two different physical phenomena. What is concerning is that the first paper was published in 1994 and the second one in 1998....

    Thursday, August 19, 2004

    Live Clean -> Die Young

    This study is rather interesting in that it parallels some fo the assumptions that polio developed in the mid-50s in the U.S. because of the access of the general population to sanitation:

    " The belief that the polio virus is spread by contact with the feces of an already infected person has been offered as an explanation for the increased incidence of polio in developed countries such as the United States during the 20th Century. According to this theory, before the advent of modern sewage treatment plants and other improvements in public sanitation, virtually all individuals were exposed to the polio virus early in their lives when they were at least partially protected by maternal antibodies. Thus, they developed mild, non-paralytic infections, probably during infancy, which provided them with lifelong immunity. However, with better sanitation, both these early infections as well as the likelihood of receiving antibody protection decreased, resulting in greater susceptibility to paralytic polio. Thus, in the words of Smith:

    Put simply, paralytic polio was an inadvertent by-product of modern sanitary conditions. When people were no longer in contact with the open sewers and privies that had once exposed them to the polio virus in very early infancy when paralysis rarely occurs, the disease changed from an endemic condition so mild that no one knew of its existence to a seemingly new epidemic threat of mysterious origins and terrifyingly unknown scope (p. 23).
    This central theory regarding the spread of polio is supported, at least to some extent, by experiences in third world countries. During World War II, for instance, U.S. and British troops stationed in undeveloped countries were much more likely to contract polio than native peoples, who apparently had already developed immunity (Paul, 1971). Even in the 1970's, when individuals from developed countries came into contact with those from a country without a modern sanitation system, the incidence of paralytic polio was about twenty times greater for those from the developed country (Nathanson and Martin, 1979).
    The above explanation for the transmission of polio is generally accepted and seems quite logical. However, the incidence of the disease in the United States during the epidemic years was very irregular, not only from year to year, but from area to area, apparently showing no relation to improvements in sewage treatment. The actual reason for this variation remains another of the polio mysteries. However, it has been suggested that this variability was possibly due to increased virulence of certain virus strains or the presence of environmental conditions that enhanced the disease's transmission (Nathanson and Martin, 1979). "


    Grand Challenge Citizenship Issue.

    I was reading the latest rules for the Grand Challenge and found out that only US citizens can be team leaders. The problem I have with this is that it excludes U.S. permanent residents from being team leaders. Not only do they pay taxes and live here, it is also apparent if you know the issues with the INS that it is sometimes beyond their control that they are not citizens as early as the law allows them to be. The law says that once you are a permanent resident, it takes 5 years before you can ask for naturalization. Right now the situation is a little bit better for people who start the process today but three years ago it was a mess. Between the time you submitted your application for a green card and getting it, it would take between two to three years to get it (check the current I-485 waiting list here.) And then you wait the five years required by law and then you have to wait between 6 or seven months to have your application Ok'ed (look up N-400 waiting list.) This is a long time given the fact that most people have lived in the country for years before even being allowed to start this process. ITAR restrictions for instance recognize the fact that if you submitted an application to being a permanent resident, you could be considered a U.S. citizen for all itents and purposes because in effect, you have made the choice to live in this country and be a full part of the economy. The rules of the grand challenge specify that no classified information should be used during the contest. So if the challenge organizers feel that no secret/senstive technology is really being transferred why would they exclude 10% of the population that is legally here and has demonstrated against the odds of a particularly inefficient branch of the government, their choice of staying here. I don't get it....

    Polyharmonic to you maybe

    I don't want to be nitpicking, but to me polyharmonic really means that after the application of the Laplacian a certain number of times, the function is zero. In here it just means that after a certain number of iteration of the laplacian, one is left with a bunch of diracs at every nodes of the spline. That's not nearly enough of a zero to me, but who am I to say this.....not a mathematician apparently.

    Multipass

    Why do I get the feeling that you do not need supercomputer blades to do this job ?

    contourlets or curvelets ?

    What I really want to know is ? are the contourlets better than curvelets ? I cannot stand the suspense....

    Catch IT if you can

    This method of catching payloads from space is not new. I recall they lost some of them, hopefully that won't be the case for this one....

    Tuesday, August 10, 2004

    Is Failure an option ?

    I don't get it, every time I read about the two recent crashes of X prize contestants, I get a sense these failures spell the end of the projects, at least from the journalist's standpoint. But why should they care, it is not governement's money and most importantly, it is because these projects are cheap that they can continue and have failures.

    Monday, August 09, 2004

    Sunday, August 08, 2004

    Saturday, August 07, 2004

    At long last a Fast Multipole Method just for you.

    The first page of this article nails exactly why other people have not looked at using this technique to solve their own equations (in my case the linear boltzman transport equation.) Maybe I can dig into this again now there is a new approach....

    Friday, August 06, 2004

    Look miserable...

    ... not because the terrorists have won in making you looking stupid but rather because, after years of research, the state of the art in identifying faces has still not been really solved (even though there are some promising leads as undertaken by Dave Donoho and Carrie Grimes.)