Domain: ucla.edu
Stories and comments across the archive that link to ucla.edu.
Comments · 1,051
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right tool for the right job...it all depends no what you're doing. For a lot of applied math (read as: PDE, linear algebra intensive, etc.) there's a lot of optimizations that are best done in code.
At UCLA's math department, the applied people have a QUIST related research program that uses Fortran77 and shell scripts, and C++ for various parts of their code to implement the Level-Set method to simulate the growth of thin films (atom by atom construction of electronic devices). The language choice seems to be due to legacy reasons: the grad student that started it so long ago used it, and the code has continued to grow ever since(ie. legacy reasons).
Although I wouldn't call it *math* research, here at MBI, bioinformatics programs run on the cluster *seem* to be written in C or C++ for the most part. I thinks it's more of the former because that's the interface for a number of bioinformatics libraries that we have licenced. Also, these things tend to be mixed heavily with shell and perl scripts; so the language is only for ease of integration with support libraries.
For most all of my undergrad work, I saw everyone use matlab, mathimatica, and their relatives for their work. In grad school, it seems to depend more on the class and the religious leanings of the mathematician involved.
There's a class on scientific computing that uses VC++ with fortran libraries from netlib (leveraged by f2c) solve some math implementation problem (tends to vary from year to year). Prof Anderson tends to by a junkyard warrior when it comes to math code generation. But then he's the mathematician's MacGuyver. (side note: Prof Anderson is a wonderful teacher and researcher - check out his page for some handy software tools and papers. Also, look at 270B for tidbits of linear algebra optimizations).
The benifit of matlab-ish programs is that you can usually implement your math structure quickly. The down side is that if you want to use any advance optimization then it near impossible. On the other hand, if you don't have a numerical analysis background, then many of the things you try to do to optimize your code in more mundane languages are probably going to be *much* slower then matlab, et al.
All of this is assuming you'r doing numerical analysis. If you're interested in abstract algebra , then I think you're stuck with maple. good program, but I don't have a review on it since I did most of my work by pencil and paper. I did use it for one of my crypto classes and found its implementation of Z_n groups very nice... although I ended up just coding it in C++ anyway
:)Also, check out the R project as it is GNU matlab.
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right tool for the right job...it all depends no what you're doing. For a lot of applied math (read as: PDE, linear algebra intensive, etc.) there's a lot of optimizations that are best done in code.
At UCLA's math department, the applied people have a QUIST related research program that uses Fortran77 and shell scripts, and C++ for various parts of their code to implement the Level-Set method to simulate the growth of thin films (atom by atom construction of electronic devices). The language choice seems to be due to legacy reasons: the grad student that started it so long ago used it, and the code has continued to grow ever since(ie. legacy reasons).
Although I wouldn't call it *math* research, here at MBI, bioinformatics programs run on the cluster *seem* to be written in C or C++ for the most part. I thinks it's more of the former because that's the interface for a number of bioinformatics libraries that we have licenced. Also, these things tend to be mixed heavily with shell and perl scripts; so the language is only for ease of integration with support libraries.
For most all of my undergrad work, I saw everyone use matlab, mathimatica, and their relatives for their work. In grad school, it seems to depend more on the class and the religious leanings of the mathematician involved.
There's a class on scientific computing that uses VC++ with fortran libraries from netlib (leveraged by f2c) solve some math implementation problem (tends to vary from year to year). Prof Anderson tends to by a junkyard warrior when it comes to math code generation. But then he's the mathematician's MacGuyver. (side note: Prof Anderson is a wonderful teacher and researcher - check out his page for some handy software tools and papers. Also, look at 270B for tidbits of linear algebra optimizations).
The benifit of matlab-ish programs is that you can usually implement your math structure quickly. The down side is that if you want to use any advance optimization then it near impossible. On the other hand, if you don't have a numerical analysis background, then many of the things you try to do to optimize your code in more mundane languages are probably going to be *much* slower then matlab, et al.
All of this is assuming you'r doing numerical analysis. If you're interested in abstract algebra , then I think you're stuck with maple. good program, but I don't have a review on it since I did most of my work by pencil and paper. I did use it for one of my crypto classes and found its implementation of Z_n groups very nice... although I ended up just coding it in C++ anyway
:)Also, check out the R project as it is GNU matlab.
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right tool for the right job...it all depends no what you're doing. For a lot of applied math (read as: PDE, linear algebra intensive, etc.) there's a lot of optimizations that are best done in code.
At UCLA's math department, the applied people have a QUIST related research program that uses Fortran77 and shell scripts, and C++ for various parts of their code to implement the Level-Set method to simulate the growth of thin films (atom by atom construction of electronic devices). The language choice seems to be due to legacy reasons: the grad student that started it so long ago used it, and the code has continued to grow ever since(ie. legacy reasons).
Although I wouldn't call it *math* research, here at MBI, bioinformatics programs run on the cluster *seem* to be written in C or C++ for the most part. I thinks it's more of the former because that's the interface for a number of bioinformatics libraries that we have licenced. Also, these things tend to be mixed heavily with shell and perl scripts; so the language is only for ease of integration with support libraries.
For most all of my undergrad work, I saw everyone use matlab, mathimatica, and their relatives for their work. In grad school, it seems to depend more on the class and the religious leanings of the mathematician involved.
There's a class on scientific computing that uses VC++ with fortran libraries from netlib (leveraged by f2c) solve some math implementation problem (tends to vary from year to year). Prof Anderson tends to by a junkyard warrior when it comes to math code generation. But then he's the mathematician's MacGuyver. (side note: Prof Anderson is a wonderful teacher and researcher - check out his page for some handy software tools and papers. Also, look at 270B for tidbits of linear algebra optimizations).
The benifit of matlab-ish programs is that you can usually implement your math structure quickly. The down side is that if you want to use any advance optimization then it near impossible. On the other hand, if you don't have a numerical analysis background, then many of the things you try to do to optimize your code in more mundane languages are probably going to be *much* slower then matlab, et al.
All of this is assuming you'r doing numerical analysis. If you're interested in abstract algebra , then I think you're stuck with maple. good program, but I don't have a review on it since I did most of my work by pencil and paper. I did use it for one of my crypto classes and found its implementation of Z_n groups very nice... although I ended up just coding it in C++ anyway
:)Also, check out the R project as it is GNU matlab.
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Re:Good sign, I hope it makes a differenceAnd what chance would a small biotech firm have against Merkh after they brought their drug to market?
The small company could also sell Merkh's drugs.
Prior to patents companies just kept thier innovations secret or tied them up in very onerous license agreements.
They still do.
The big win for patents is that they force disclosure in return for the monopoly right.
Nowadays it isn't required to fully explain the inner workings of the invention in the patent, and that's a trick very used in software patents.
Also, since we have the rather amazing correlation
Correlation doesn't imply causation.
how techology and quality of life have advanced far more in the 300 years since the development of IP rights than it did in the 5000 years between the invention of agriculture and the development of the concept of the patent.
What about education, church-state separation, *free commerce*, etc. By the way, check this writing of the same authors that expains James Watt could actually have delayed industrial revolution 30 years because of his mighty patent power. Don't miss the bit about Hornblower's better engine.
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Kiss and say goodbye to Java language!!
No Java, no JSP man. Simply use PHP for web development.
Forget Java man and go to PHP!
PHP is 4 times faster than Java technology 'JSP' (Java server pages).
This tallies because compiled "C" program is 4 times faster than Java.
Moreover, PHP is getting the object oriented features of Java language.
The real usefulness of Java is 'Java applets' which run on client browsers but on the server side you simply use PHP.
PHP is a very lightening fast object oriented scripting language. PHP is 100% written in "C" and there is no virtual machine as in Java. Nothing can beat "C" language ("C" is a language which never dies!!)
(Java is just another language. The PHP project needs millions of Java programmers who can add the Java's language features like inner classes, static, private, protected and others to PHP. PHP already has some of java' features).
Java programmers will really "LOVE" PHP as PHP class is identical to Java's class keyword.
Read the benchmars of Java JSP and PHP. PHP tops in the speed!!
Read the doc here and mirrors at [1], [2], [3], [4]. -
Re:How can you see so close to the big bang?There is no "universal point of origin". The Big Bang was not a concentrated lump of stuff somewhere out in the middle of empty space, which subsequently exploded (with a spherical wavefront marking the "outer edge of the explosion"). Rather, all of space was compressed into a point, and space expanded (instead of matter exploding), like the surface of an inflating balloon. Think of an ants crawling randomly all over across the surface of such a balloon. At any given time, ants which were crawling on the surface when the balloon was small are still crawling past any given point --- that's like why we still see photons.
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More information
More information can be found at (including a cosmology tutorial):
http://www.astro.ucla.edu/~wright/cosmolog.htm#New s
This press release was mentioned in a post in the previous slashdot story yesterday. -
Schedule of Press Release
It is my understanding that the NASA press release will take place tomorrow (Tuesday 2/11) at 2pm EST. The initial press release was scheduled for Thursday 2/6, but was postponed due to the shuttle disaster. You may find more information at the following URL after the press release:
http://www.astro.ucla.edu/~wright/cosmolog.htm#New s -
Kiss and say goodbye to Java language!!
No Java, no JSP man. Simply use PHP for web development.
Forget Java man and go to PHP!
PHP is 4 times faster than Java technology 'JSP' (Java server pages).
This tallies because compiled "C" program is 4 times faster than Java.
Moreover, PHP is getting the object oriented features of Java language.
The real usefulness of Java is 'Java applets' which run on client browsers but on the server side you simply use PHP.
PHP is a very lightening fast object oriented scripting language. PHP is 100% written in "C" and there is no virtual machine as in Java. Nothing can beat "C" language ("C" is a language which never dies!!)
(Java is just another language. The PHP project needs millions of Java programmers who can add the Java's language features like inner classes, static, private, protected and others to PHP. PHP already has some of java' features).
Java programmers will really "LOVE" PHP as PHP class is identical to Java's class keyword.
Read the benchmars of Java JSP and PHP. PHP tops in the speed!!
Read the doc here and mirrors at [1], [2], [3], [4]. -
The System is Down (almost forgot!)
One more System is Down link!!!!
Hooray for cache =)
-Berj -
The System is Down
What could better commemorate the slashdotting of homestarrunner than watching sbemail43? =)
Here's a mirror of sbemail43 - "The System is Down"> =) Enjoy!
-Berj -
Cute, but no.
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Re:HOW THIS WORKS-Links.
Microwave Phase Conjugation using Discrete Superconducting Elements for Retrodirective Antenna Applications
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 46, NO. 11, NOVEMBER 1998 Microwave Phase Conjugation Using Antenna Arrays
Microwave Phase Conjugation Using Artificial Nonlinear Microwave Surfaces
A Retrodirective Array Using Balanced Quasi-optical FET Mixers with Conversion Gain
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Re:HOW THIS WORKS-Links.
Microwave Phase Conjugation using Discrete Superconducting Elements for Retrodirective Antenna Applications
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 46, NO. 11, NOVEMBER 1998 Microwave Phase Conjugation Using Antenna Arrays
Microwave Phase Conjugation Using Artificial Nonlinear Microwave Surfaces
A Retrodirective Array Using Balanced Quasi-optical FET Mixers with Conversion Gain
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Hindenburg Myth applying to GMClick here to read the new belief on the Hindenburg tragedy. Essentially, "material used to coat the 'skin' of the airship, not hydrogen, was the cause of the disaster" - my father told me about this after watching a special on Discovery Channel a while back, which prompted my quick google search (I'm sure you can find more info online than just this one link - I just took one of the top results of "Hindenburg + hydrogen"). Of course, knowing the populace of this "1st" world country, it'll still take a lot of convincing before we advance towards these savior autos. Viva hybrid!... ity?...
-e
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Simlar
Those who are just interested in learning japanese check out jwpce (text editor for typing japanese), Kanji gold (flash card program), Pera Pera Penguin(PDF files covering different japanese phrases)
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Re:What if.....
I've often wondered lately if perhaps gravity is both a repulsive and an attractive force. For local (i.e. interstellar) distances, the attractive force prevails. But for really vast (intergalactic) distances, it might act as a repulsive force. This could partly explain why the galaxies are accelerating away from each other.
Actually, that is exactly correct. We used to believe that the galaxies were receding from each other, but at a decelerating rate. Now that we have evidence that they're actually accelerating away from each other, the simplest way to account for that is to return to a part of Einstein's original theory of general relativity that he discarded, the "cosmological term". This term makes gravity act repulsively on large scales. Read this FAQ.
Physicists don't have much of an idea what dark energy is... maybe it's just gravity, and Newton's law needs an amendment.
Indeed! The presence of a cosmological term in the laws of gravity (amending Einstein's laws, not Newton's) would amount to "dark energy". (However, the cosmological term alone may not be sufficient to account for the observed properties of dark energy.) -
Re:Dark Matter?Could you provide some sort of support for that claim?
Aside: Really, it's not about the egos of scientists, or the perfection of our telescopes and instruments. Goodness knows, if they were so perfect, we wouldn't be begging for money to build new and better ones!
:)The link that pyrrho mentioned describes the basic reasons why baryons can't be all of the hypothesized dark matter. And since 1996 (when the article was written), the evidence has become vastly more convincing. I'll attempt to summarize.
Sure, we could hypothesize that the Universe is filled with "dim, normal stuff" like brown dwarfs, white dwarfs, lost airline luggage, missing socks, dryer lint... but we're just not able to see them. Fair enough. But there is a limit to this argument for numerous reasons.
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There are not enough baryons in the Universe. The Big Bang only made so many baryons, and this is something we can measure. The limits on the number of baryons in the Universe are quite tight -- only, say, 5% of the mass needed to give the Universe an uncurved geometry.
Okay, so maybe we just live in an empty, open Universe! But numerous measurements of the curvature of the Universe, in particular recent observations of the cosmic microwave background itself suggest that the curvature is not open but uncurved. So we live in a Universe with plenty of gravitational matter of some form or another. Aside: we are gathering a huge amount of information by looking at the angular sizes of the bumps and dips in the cosmic microwave background, which is fossil radiation from the Big Bang and a few percent of the static you see on your TV when tuned to a blank UHF channel. This page shows what the CMB power spectra (that is, how many inhomogeneities occur at a given angular size) look like, and how changing various cosmological parameters has an effect on the spectrum you'd expect to see. Try out changing the baryon density -- the effect is quite pronounced. It also says that the Universe has the number of baryons that Big Bang theory says it should have.
- Even if we can't see brown dwarfs (or basketballs, for that matter) by their reflected light, we CAN infer their existence by their gravitational interactions with light, i.e. gravitational (micro)lensing. It's not that we "haven't looked hard enough" -- but rather that "if the Universe was full of brown dwarfs, there'd be tons of observable microlensing events". But microlensing events are exceedingly rare. In this case, the null result is interesting, because it highlights that baryonic matter is not as prolific as we want/need!
So this makes us all feel a bit uncomfortable, because either some of the fundamental tenets of cosmology are flawed (even though they explain nearly all of the observable Universe, right down to the abundances of the elements and the large scale structure of galaxies and the cosmic microwave background, the recession of galaxies etc.)
... OR ... the Universe is mostly filled with matter what is unlike anything we yet know how to explain.It's going to be a fun ride!
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There are not enough baryons in the Universe. The Big Bang only made so many baryons, and this is something we can measure. The limits on the number of baryons in the Universe are quite tight -- only, say, 5% of the mass needed to give the Universe an uncurved geometry.
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Re:new estimates?!!No, it's how the error estimates are reported. The HST key project that estimates an age around 13 billion years also stipulates +/- 10%, corresponding at most to ONE standard deviation, i.e. the 68% confidence level. This study is reporting their error bars at the 95% confidence level, which corresponds to two standard deviations, so the errors appear twice as large. The "13-14 billion year" age you report would have uncertainties of almost 3 billion years in either direction at the 95% confidence level. We have to compare apples to apples here!
There is another very important point to recognize here. The HST Key project results (based upon Cepheid variable stars) is independent of the measurement/modeling of the ages of the oldest stars of Milky Way halo stars and clusters. Sure, both measurements each have significant systematic errors, but their uncertainties come from entirely different things! So the fact that they agree is quite reassuring. It also means that the measurements can be combined, at least to some degree.
With the newest generation of instruments and telescopes observing the Universe from radio waves to gamma rays, there will be new, independent methods of measuring the age and fate of the Universe. Already measurements from Type 1a supernovae are narrowing the uncertainties in some cosmological parameters. Other methods that currently yield very large error bars, but will be pivotal in the next few years are gravitational lensing (a detailed description here) and the Senyaev-Zeldovich effect (some details here).
When and if we get to the point where all methods yield the same result, we'll have our answer. In the meantime, if you just quote the formal results from just a single group, from a single type of argument/measurement, the systematic errors are going to be large, particularly when you're dealing with anything on cosmological scales!
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About that syllogism...
I'll try to wrap up one tiny detail....
The syllogism and its little brother the enthymeme date back to ancient Greece and are styles of argument. The reason the syllogism gets criticized to the point of being deprecatory is that it is easily abused.
Here:
Major premise: The universe is older than 6,000 years if some of its components took longer than 6,000 years to form.
Minor premise: The gas giants took less than 6,000 years to form.
Conclusion: The universe probably (more so than yesterday) took less than 6,000 years to form.
To me, there are several logical flaws there, and this has not a thing to do with religion. The main one is that the major premise is false; the theories concerning the age of the universe are not based on the sum of series of events. You may be making this false assumption because (to my understanding) the 6,000-year version of creationism is derived from how long various individuals lived, added to their descendants, and so on.
So the gas giants might never have formed, the estimates for the age of the universe would not change because they are indifferent to gas giants. Really, the formation of the planets is a bit trivia in the view of the universe, and the difference in formation time proposed here, mere millions of years, are the 0.01% insignificant blink of an eye to a universe thought to be over 10 thousand million (billion) years of age, and a solar system of a sprightly 4.5 billion (again with a "b").
Another trivial bit of semantics is that you misuse the word "hypothesis." Science really doesn't use hypothesis in this way, and when scientists speak of theories they don't mean educated guess, but a framework to explain a fact. So the age of the universe is a fact to a very high degree of certainty; it is older than 6,000 years by billions; and various theories strive to explain the nature of or refine the fact. But whether a theory of good or bad does not alter the fact, and the age of the universe is something so well established that it is inconceivable it will someday turn out to be 6,000 years. Besides the huge difference between the estimates, there's enough evidence on earth -- even the weathering of a mountain takes millions of years -- the pyramids haven't weathered much in that time -- and I won't even bring up the fossil record.
But again, even if these events happened faster than we can imagine, the age of the universe is judged by independent data.
The only remaining hope for a doctrinaire 6,000-year view would be that the universe and earth were created pre-aged, but I doubt the Bible supports that view. I don't care how many people believe it, the majority has erred often enough before, is the name of many causes. You acknowledge that truth isn't determined democratically anyway -- then turn around and say "I am being persecuted for what are mainstream beliefs in much of the US." No, you are being criticized (persecuted? that's a little much) not for relating "popular" beliefs but for your faulty logic concerning astrophysics, and science generally. Don't take refuge in "mainstream." And I am not claiming that God lies, just that falliable humans don't get the message right sometimes.
I would think it obvious that the Bible makes heavy use of metaphor, and that things like the 6 days of creation may not be at all literal. Of course I'm not the first to wonder about this. But I think more and more people will eventually accept that the Earth is old and move on to that evolution debate, or something else. The truth of the Bible is hardly imperiled. -
Law Professor on 2nd Amendment
Professor Eugene Volokh provides the individual rights view of the 2nd amendment.
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Re:Not that impressive
I sincerely hope that soon small-to-medium enterprises can own supercomputers. With all the low budget physics stuff going on at Universities around the world, cheap supercomputing can only be a good thing.
Actually they can with software like that from Dauger Research, Project Appleseed and Wolfram Research with gridMathematica
The cool thing here is that this code can be run on all of the desktop computers that already occupy companies and universities world wide allowing for easy access to supercomputer level computational speed (for those problems that can be attacked using parallel computation of course) using the same computers normally used for productivity.
Very cool.
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Re:Stupid assumptions
And the endless arguments between Picard and Q about the humans having "evolved" past violence and aggressive behaviour.
Exactly right. And it is not the only place where I have seen this thought growing (college history courses, popular media, etc.). It is this line of reasoning that I find very troubling. As I stated in reply to another post in this thread, I do not believe that people have changed much at all throughout history, though some people try to read in evolutionary changes in the "progress" they see in society. I am not attempting in this arguments to confront macro-evolution (history does not necessarily serve as a good avenue for this, as you have pointed out), but merely to point out potential flaws in our view of the past 10,000 - 25,000 years of human culture. Even the methods at which we have placed dates for the human development may be considerably wrong. On the same token, the commonly held belief (among creationists) in a 6500 year old earth may prove to be wrong as well.
While I believe the 7-day creation of the earth, there still remain many questions as to exactly how everything progressed from there. There are many question marks even within the Bible, especially in regards to giants, the Nephiim, the "Sons of God", etc., that I believe are worth looking into. We may find that there is much knowledge to share on both sides of the camp, and the truth may very well lie between what both sides how as their absolute truths. Afterall, even the interpretation of Genesis 1:1 is believed to be quite different than what was originally thought -> "In the beginning, God created the spaces and the matter" (instead of "heavens" and "earth") gives a more interesting and enlightening meaning, especially combined with what we know about science today (it is believed that outer space is not actually empty as has been supposed: Outer Space in a Bottle).
There are also frequent references throughout the Bible to "God spread out the heavens" which one could tie into a concept of a "Big Bang" as the stars where spread out across the universe.
I am not trying to make a conversion here or anything. I am merely trying to point out that there are some interesting things that might be gained from the Bible if it is not catagorically dismissed, and likewise, all of the scientific discoveries, evolutionary or otherwise, should not be thrown out either. I believe there is a lot of common ground that can be researched if we keep a somewhat open mind. This is where, getting back to the article, it would be nice to actually see all of the evidence. While the current theory may be vastly flawed, the actual evidence could help develop the next, more accurate theory.
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Re:later on the nature channel
Laugh at sensors hopping...
It's very funny that you link to the DARPA SHM program. The Forbes "Sensors Gone Wild" article that Slashdot linked to today is talking about work done at the Center for Embedded Network Sensing at UCLA (and the closely associated UCLA LECS lab, also run by Deborah Estrin). Now, a few of us lowly graduate students working at the UCLA lab/center also work for Sensoria Corp, which was one of the main contractors for the SHM project. A lot of the research was very complementary. I'll plug my own research here -- the fine grained network time synchronization that we developed at UCLA/LECS is public domain and also made its way into the SHM project. There's other crossover as well (e.g. some of the acoustic ranging work); check out Sensoria's publications page.
I was at the SHM demo on an army base this past March and again this past August, and let me tell you, seeing those things actually hop is quite exciting. Especially when you're the one with your finger on the "ARM ALL" button :-).
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Re:later on the nature channel
Laugh at sensors hopping...
It's very funny that you link to the DARPA SHM program. The Forbes "Sensors Gone Wild" article that Slashdot linked to today is talking about work done at the Center for Embedded Network Sensing at UCLA (and the closely associated UCLA LECS lab, also run by Deborah Estrin). Now, a few of us lowly graduate students working at the UCLA lab/center also work for Sensoria Corp, which was one of the main contractors for the SHM project. A lot of the research was very complementary. I'll plug my own research here -- the fine grained network time synchronization that we developed at UCLA/LECS is public domain and also made its way into the SHM project. There's other crossover as well (e.g. some of the acoustic ranging work); check out Sensoria's publications page.
I was at the SHM demo on an army base this past March and again this past August, and let me tell you, seeing those things actually hop is quite exciting. Especially when you're the one with your finger on the "ARM ALL" button :-).
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Re:later on the nature channel
Laugh at sensors hopping...
It's very funny that you link to the DARPA SHM program. The Forbes "Sensors Gone Wild" article that Slashdot linked to today is talking about work done at the Center for Embedded Network Sensing at UCLA (and the closely associated UCLA LECS lab, also run by Deborah Estrin). Now, a few of us lowly graduate students working at the UCLA lab/center also work for Sensoria Corp, which was one of the main contractors for the SHM project. A lot of the research was very complementary. I'll plug my own research here -- the fine grained network time synchronization that we developed at UCLA/LECS is public domain and also made its way into the SHM project. There's other crossover as well (e.g. some of the acoustic ranging work); check out Sensoria's publications page.
I was at the SHM demo on an army base this past March and again this past August, and let me tell you, seeing those things actually hop is quite exciting. Especially when you're the one with your finger on the "ARM ALL" button :-).
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Re:later on the nature channel
Laugh at sensors hopping...
It's very funny that you link to the DARPA SHM program. The Forbes "Sensors Gone Wild" article that Slashdot linked to today is talking about work done at the Center for Embedded Network Sensing at UCLA (and the closely associated UCLA LECS lab, also run by Deborah Estrin). Now, a few of us lowly graduate students working at the UCLA lab/center also work for Sensoria Corp, which was one of the main contractors for the SHM project. A lot of the research was very complementary. I'll plug my own research here -- the fine grained network time synchronization that we developed at UCLA/LECS is public domain and also made its way into the SHM project. There's other crossover as well (e.g. some of the acoustic ranging work); check out Sensoria's publications page.
I was at the SHM demo on an army base this past March and again this past August, and let me tell you, seeing those things actually hop is quite exciting. Especially when you're the one with your finger on the "ARM ALL" button :-).
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Re:Better for the enviroment?When hydrocarbons are burned throroughly, the only waste products are hydrogen and carbon.
Combustion produces CO2 and H2O, according to a UCLA hydrocarbon combustion study and my chemistry textbook, the latest edition of Zumdahl Chemisty. (Zumdahl is a professor at U of I: Urbana Champaigne.)
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This is old news at UCLA
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Re:Benchmarks?
Are there any benchmarks to prove this claim? It would be interesting to see a comparison - especially if made by an independent party.
Clock for clock, proving that MHz is not an absolute comparable measure, here you can see both G4's and G3's of lower MHz beating Intel Pentium III's which are clocked 50% higher than the G3 beating them!
In fact, when the code is RISC optimized, a 450MHz G3 manages to run 74% faster than a 450MHz PII.
Now imagine a program optimized for SMP and AltiVec on Dual 1.25GHz G4's. I know the cheapest Dell can most likely beat the most expensive Apple, but the current situation leaves Apple with little it can do.
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Re:Apple Chips
"Mhz doesn't matter"
The MHz Myth that Apple talks about is not about trying to say that "Mhz doesn't matter", it's about the fact that MHz cannot be used as a direct comparison between architectures.
Of course MHz (brute force) matters. But what also matters is smart design.
I think showing a 333MHz G3 running faster than a 500MHz Pentium III, kinda proves the MHz Myth is just that. Bear in mind, that the G3 is not AltiVec equiped! So not getting a huge vectorized benefit here.
If you think that's impressive, look at the G4! I can't wait to see what CPU Apple actually unleashes next.
I'm astonished that there are actually people who think MHz is THE sole number to go by.
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Re:It hasn't been said,
Actually, in this case, it would be an Appleseed cluster.
Imagine clustering for anybody. -
Re:Everyone will still see it as slow
This "megahertz myth" crap was around when I had a 33 MHz 68040 Performa 640, and my 486/DX2 66 blew the shit out of it.
Therefore, with my minimum sample size of 2 machines, I can deduce that all processors can be compared with MHz alone. Further, all architectures perform exactly the same, MHz for MHz across the board for similar instructions and they all scale in a linear fashion regardless of the ratio of core speed to main memory speed or other similar limitations. There is also no such thing as this "bottleneck" crap. Bottlenecks r what yer get when your old Chev brakes down on tha intastate and bloks a lane.
PS, this is sarcasm.
NASA did a study to find the best cost/performance for their Fortran number crunching.
AltiVec is a beast. A 500MHz G4 using AltiVec ran 6.9 times faster than a P3 800 and 3.7 times faster than a 500MHz Alpha 21264. The G4 worked out to be 5.3 times cheaper per FLOP than the P3 and 8.4 times cheaper than the Alpha. Although there is no mention of Intels SIMD within this documents and the FORTRAN compilers at the time of the documents writing were very limited in their abilities to vectorize FORTRAN code to make better use of the AltiVec.
Here is a 1GHz G4 performing up to 10 times faster than a 2GHz P4 while querying a DNA database and 2 times faster at their fastest measured rates.
Saying that the MHz Myth is a Myth, based on a single experience is really idiotic. Anyone who has at least failed the first semester of a CS course would know that different architectures cannot be judged on MHz alone. Hell, even comparing different revisions of the same architecture family cannot be judged on MHz alone (a 33MHz 486DX is much faster than a 33MHz 386 for example, ignoring floating point of course). Wanna talk about CISC vs RISC vs CISC-wrapped-around-RISC?
Here are some G3's (as low as 333MHz) and a 450MHz G4 running faster than a P3 500MHz. There are plenty of graphs and numbers here which might put a fright into you Hrothgar.
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UCLA
apparently ucla's school of engineering and applied science has received a lot of... sponsorhip, from microsoft, through microsoft's msdn academic alliance, which provides hardware and software to schools at no cost.
the school's computing facilities just recently opened a new computer lab, stocked with new-ish hardware and loaded with windows xp. (the four other labs have windows nt, but dual boot into linux. haven't checked whether the new winxp lab includes linux.) furthermore, they offer downloads of visual studio.NET and windows xp at no charge for students.
at least the CS department's upper division course on operating systems is still based on linux. and various unix flavors power most of the campus' central systems.
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UCLA
apparently ucla's school of engineering and applied science has received a lot of... sponsorhip, from microsoft, through microsoft's msdn academic alliance, which provides hardware and software to schools at no cost.
the school's computing facilities just recently opened a new computer lab, stocked with new-ish hardware and loaded with windows xp. (the four other labs have windows nt, but dual boot into linux. haven't checked whether the new winxp lab includes linux.) furthermore, they offer downloads of visual studio.NET and windows xp at no charge for students.
at least the CS department's upper division course on operating systems is still based on linux. and various unix flavors power most of the campus' central systems.
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UCLA
apparently ucla's school of engineering and applied science has received a lot of... sponsorhip, from microsoft, through microsoft's msdn academic alliance, which provides hardware and software to schools at no cost.
the school's computing facilities just recently opened a new computer lab, stocked with new-ish hardware and loaded with windows xp. (the four other labs have windows nt, but dual boot into linux. haven't checked whether the new winxp lab includes linux.) furthermore, they offer downloads of visual studio.NET and windows xp at no charge for students.
at least the CS department's upper division course on operating systems is still based on linux. and various unix flavors power most of the campus' central systems.
-
UCLA
apparently ucla's school of engineering and applied science has received a lot of... sponsorhip, from microsoft, through microsoft's msdn academic alliance, which provides hardware and software to schools at no cost.
the school's computing facilities just recently opened a new computer lab, stocked with new-ish hardware and loaded with windows xp. (the four other labs have windows nt, but dual boot into linux. haven't checked whether the new winxp lab includes linux.) furthermore, they offer downloads of visual studio.NET and windows xp at no charge for students.
at least the CS department's upper division course on operating systems is still based on linux. and various unix flavors power most of the campus' central systems.
-
UCLA
apparently ucla's school of engineering and applied science has received a lot of... sponsorhip, from microsoft, through microsoft's msdn academic alliance, which provides hardware and software to schools at no cost.
the school's computing facilities just recently opened a new computer lab, stocked with new-ish hardware and loaded with windows xp. (the four other labs have windows nt, but dual boot into linux. haven't checked whether the new winxp lab includes linux.) furthermore, they offer downloads of visual studio.NET and windows xp at no charge for students.
at least the CS department's upper division course on operating systems is still based on linux. and various unix flavors power most of the campus' central systems.
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Re:Why this isn't a joke...
After all, how many handicapped parking places does the mall need?
Given the number of people abusing handicapped parking places, either by getting a handicapped placard (without actually having a handicap), stealing a placard, or just parking there and not giving a shit, the actual number of spaces needed is going to get inflated, just so that a REAL handicapped driver has a chance of getting a spot when they need it.
Anyone recall the UCLA scandal where university football players were using placards to get prime parking spots? Yes, some of those placards were gotten under false pretenses. -
Re:You are WAY off base.I never obey laws that I don't like unless I'm coerced by being frightened of the consequences of disobeying those laws. If an idiotic law is passed that doesn't make any sense is passed then the State must do two things to get me to obey it:
1. They have to actually enforce it.
2. They have to attach scary penalties to it.
I don't disobey very many laws, if any (far be it from me to admit to illegal activities in a public forum). However, when I do, it is because they are laws that any thinking person knows are either nonsense or evil.
We used to have some really wonderful laws in this country like The Fugitive Slave Act or the Executive order which required the Internment of Japanese Americans. These laws were evil. People who didn't help enforce them and actively disobeyed them were brave and noble.
You seem to have substituted a sense of right and wrong for blind State-worship.
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Re:OFFTOPIC!!Bull-puckey. The agenda pushed by the USA PATRIOT act is indistinguishable from the agendas of the people who were responsible for such crimes against free speech as the Palmer Raids of 1919, Executive Order 9066 of 1942 which interned all Japanese-Americans, the House-Unamerican Activities Committee, the McCarthy hearings, and COINTELPRO.
I see us traveling down the same dark path now. I know this Santayana quote is almost cliche now but it bears repeating: "Those who forget the past are condemned to repeat it."
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Re:Best way to stop Palladium
I'd like to bring back an old analogy I once heard with Clipper Ships and Galleons. Both were shipping and both had piracy problems on the high seas. The Galleons had armaments and even more heavily armed escorts, perpared to fight off any pirates. The Clipper Ships were simply FAST, and couldn't be attacked or boarded by pirates. Both were viable shipping models, and both got the cargo there. But the armed escort of the Galleon did *nothing* beyond make sure the cargo got there. The speed of the Clipper made sure the cargo got there, plus it got there faster, delighting the customer.
I don't know what your analogy has to do with fighting Palladium. Should we dismiss your analogy if it is built on bogus information?
First, I suspect you will find that the period of the galleon didn't overlap with the period of the clipper ship.
So the two different kinds of saliing ships never competed with one another. You say the clipper, "couldn't be attacked or boarded by pirates"? Umm. Can I tell you a feature of sailing ships? They depend on the wind. No wind, the sailing ship just sit there, drifting. It is called being becalmed. A becalmed ship is extremely vulnerable to being boarded.
Now maybe by "galleon" you merely meant, big old slow merchant ship that is not a clipper. Maybe you think I am being really pedantic. But picking the wrong metaphors can really wound a good cause. Consider the story of Ken Keyes Jr.book "The 100th Monkey" . The intent behind Keyes book was to work toward disarmament and world peace. But, rather than think this was a worthwhile cause, in and of itself, he hitched his fight to a crazy analogy based on a bogus account of a psychic phenomenon that he took seriously. It made him look ridiculous and considerably undermined his argument...
The fraud is a particularly interesting one, but it is off-topic.
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Re:Good old slashdot.Uh, I remember a few things from history class, like:
- The Sedition Act of 1798
- The Espionage Act of 1917
- Executive Order 9066
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Re:Leonard Kleinrock
Offtopic, but....
Okay, "LK" may be a respectable and contributing member of the community, but this picture is just way too funny for me to take him seriously.... -
Kleinrock *DID* Invent The Internet
A reply on the same thread: For geeks, you slashdot kids display an embarrassing lack of knowledge about a principal subject of geekdom. Kleinrock is indeed considered one of a handful of people who literally and truly invented the Internet. Others were Vint Cerf, Jon Postel, Bob Kahn, and Lawrence Roberts. The Internet didn't come from a vacuum: buy a book, take an hour, and learn about its history.
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Re:KleinrockWhat happened to the "I'm feeling lucky" button on Google ?
...anyway
At age 6 he was stealing hardware
"In addition, he needed an earphone which he promptly appropriated
from a public telephone booth."
to listen to free music
""free" music came through the earphones - no batteries, no power,
all free! An engineer was born. "
Nice story if you haven't seen it before, a little overblown though -
Don't You Know Kleinrock?
He's known as "the Father of Modern Data Networking." Says so right here on his site.
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Leonard KlienrockBTW does anybody knows of 'Leonard Kleinrock' described as "one of the original founders of the Internet" in the article and an expert witness ?"
Yeah, he used to beat the crap out of me . Of course I was a lowly green belt in Shotokan Karate, and he was a mightly black belt.
Seriously, he is a professor at UCLA and describes himself as "the Inventor of the Internet Technology". Not the inventor of the Internet itself mind you. Maybe think of him as the Heinrich Hertz of the Internet, not the Marconi.
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Leonard Kleinrock
Here's his home page where he does claim to have invented the Internet.
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Kleinrock
Leonard Kleinrock.
Unfortunately the RIAA page is /.'ed. Great way to use that Berman-Coble DOS self-help!