Domain: utk.edu
Stories and comments across the archive that link to utk.edu.
Comments · 333
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Avoid time wasting pedant wannabes
Ummm... firstly, a true pedant wouldn't use the ill-defined term "average."
Secondly. If you have a physicist's training then you should certainly know that the mean value theorem (aka the fundamental theorem of Calculus) says that the speeder must have at equalled their median velocity at some point in the interval, even if we don't know what that point is.
So yes, they measure it - they take measurements and then deduce a minimum value for the car's maximum velocity. That's no different from any other measurement that physicists do in the lab using basic deductive tools. -
Re:Cray is dead end, you're welcome to it, MS
Oh really? Perhaps you should check the latest Top500 list.
From the 11/2005 TOP500 list:
#6 - Cray XT3 - 38TF/s
#10 - Cray XT3 - 20.5TF/s
#14 - Cray XT3 - 17TF/s
#17 - Cray X1E - 15TF/s
Of course Linpack doesn't stress other important aspects of a supercomputer such as memory bandwidth and interconnect latency. The HPCC benchmark is a better measure of performance on real-world applications. Cray systems do very well on HPCC as well. -
Re:This is stupid
evolution has deep scientific background, despite not being a proven fact.
Evolution is not a proven fact in the same way that gravity is not a proven fact. The word "theory" throws people because the scientific definition is different than the plain English.
In plain English, a "theory" is defined as "An assumption based on limited information or knowledge; a conjecture.". Pretty clearly not something you should put any undue trust into.
In Science, a "theory" is "A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.". Note the emphasis on being repeatedly tested, and that it can be used to make predictions of natural phenomena.
In short, the Scientific definition of theory pretty closely matches the English definition for fact: "Knowledge or information based on real occurrences". Since a Scientific theory has been repeatedly tested, we can be pretty sure it's pretty factual.
Or, put another way, a scientific theory can never be proven 100% right because we can never be absolutely sure that all aspects of the theory are correct. Isaac Newton cooked up the first mathematically supported theory of gravity, a theory that works perfectly well on Earth and in simple circumstances. But, in space, with extreme velocities and accellerations, Newtonian gravity theory becomes ambiguous and inaccurate.
It was Albert Einstein's Theory of General Relativity that refined the older Newtonian theory and filled in the missing pieces.
If you ever have to deal with ID nuts, see if you can't get them to state that Evolution is "only a theory". Then, being very, very obvious and very quiet, hold out a pen, and let it drop on the table. Then, with the flattest, most rude, deadpan voice you can muster, say "Gravity is just a theory".
Slowly pick it up, and drop the pen again. And again. Let them blab their way to silence. (it might take a while)
Then, go click the lightswitch on and off again. Explain to them that electro-magnetism is more (gasp!) theory, not proven to be 100% true.
Then, ask them why they trust science when they drive their car, and they trust science when they swallow an aspirin, and why they trust science when they fly, or watch television, or drink floridated water, and why they trust science when they drive their tractors, and why they trust science when they drink homogenized milk, and why they trust science when they don their clothes made with nylon, and why they trust science when they talk on the cordless or cellular phone, and why they trust science when they swallow a vitamin pill, and why they trust science when they mow their lawns, and why they trust science when they watch dishes with their dishwasher, and why they trust science to identify the history of events when solving a crime, and why they trust science to identify the rightful father of a baby using DNA testing.
And then ask them why they don't trust science when to identify their other ancestry.
(PS: definitions come from Dictionary.com) -
Internet Backplane Protocol [IBP]
You might also check out the Internet Backplane Protocol, or "IBP", which was designed to store massive amounts of data in a generic "cloud".For instance, more than 18 months ago, it was already moving 1TB per week on Internet2, and this past week was at 1.896TB.
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Internet Backplane Protocol [IBP]
You might also check out the Internet Backplane Protocol, or "IBP", which was designed to store massive amounts of data in a generic "cloud".For instance, more than 18 months ago, it was already moving 1TB per week on Internet2, and this past week was at 1.896TB.
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Re:What a bunch of FUD
The miss penalty times I googled for review site where they'd benchmarked it. If you look, you can probably get more accurate numbers from Intel. For the disk latency, the manufacturer of a disk will generally report some sort of access latency number, but overall, a "fast" 7200 RPM disk has a latency of about 8 ms.
So far as how malloc() works, well, it is open source. But some discussion on malloc design can be found at http://gee.cs.oswego.edu/dl/html/malloc.html. More simple information can be found linked at http://www.cs.utk.edu/~plank/plank/classes/cs360/l ecture_notes.html (again, just a quick google).
Mostly, it comes down to that my area is systems and architecture. My job is to know all those little details about how things interact. This was just a quickie. No guarantees it is right--I'm using other people's numbers, and just my recollection of how malloc() behaves. If this were more serious than /. then I'd dig through Intel's processor manuals for more exact numbers, figure out which (if any) of those latencies can happen in parallel, measure things myself to verify, etc. I'd also write a small program to do a lot of mallocs and frees and see what addresses are returned to verify the locality properties.
If I were really really serious, I'd come up with a benchmark program that allocates and frees memory, of various sizes with various working sets and object lifetimes, and measure the execution time for both Java and C. I'd use something like VTune (http://www.intel.com/cd/software/products/asmo-na /eng/vtune/index.htm) or SimICS (http://www.virtutech.com/) (with a timing model, say GEMS (http://www.cs.wisc.edu/gems/tutorial.html)) to analyze exactly where the differences are coming from.
And then I'd write it up and submit the results to SIGMETRICS, PLDI, OOPSLA, or some other conference, because I just spent a metric butload of time tracing down shortcomings in the GC implementation of various JVMs as compared to programmer managed memory allocation. If somebody is willing to pay me, I still might, but as it is, back of the envelope is all you'll get. -
Re:Cigar Shaped?A cigar shpaed planetoid, that's awesome!
Is this something new? Isn't that what Mars's satalites are?
http://csep10.phys.utk.edu/astr161/lect/mars/moons .html -
Re:Proof of Big Bang
The grandparent has a point. The assumption that the only, or at the very least major, reason for frequency change is motion, has to be made for today's mainstream cosmological position to work.
If you're going to question that, you'll have to quesion everything from e = mc^2 to f = ma!
*laugh* There's no domino effect involved here! Even the odd people who refuse the validity of evolutionary theory don't, by and large, run off to NASA and scream that they'll never achieve orbit because their physics of gravity is wrong.
Radial velocities do seem to give Doppler shifts, so there's no reason to think that velocities don't give redshift. There are, however, a few odd cases which give very strange results if velocities are the only thing underlying redshift.
If we take galactic clusters, then either no matter which way we look, late-type (I believe this is the right way 'round) spirals group on the far side of the cluster and early-type on the near side. Are we at the center of the universe? Unlikely, but that's a possible implication of what we see if we don't admit the possibility of other causes of redshift.
Other oddities that merit investigation are the "K Effect", which is redshift in hot stars (unless all hot stars are running away from us), and the appearance of concentric "shells" around our galaxy in larger-scale structure.
I personally would hold the cosmological principle in higher regard than any particular current theory. That is to say, the universe is not pointing at us. Which is why I'm willing to say that the aforementioned assumption may not hold. Which could have profound implications.
And so on
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Re:let me second that
What makes a pattern important is that it is widely recognized - it allows not only for reusable code, but more importantly, reusable thinking.
Yes, patterns are important, and it is important that they are widely recognized. That's why many languages have them built in. Hence, the ancestral comment that most of those patterns aren't needed in Lisp. But instead of telling you to use the correct tools for the job, the GoF book amounts to "structured programming in Fortran 77" or "object oriented programming in assembly language".
Similarly, I think it is progress to have GoF broadly understood. This is usually best accomplished by writing a book that people can read about the subject, and GoF did us that courtesy.
I think it is merely symptomatic that the GoF book even had to be written: it shows that the industry is based on the wrong kinds of programmers, the wrong approaches, and the wrong tools. The book may well help improve software development slightly in the short term, but it doesn't represent progress towards solving the fundamental problems with software development.
What is currently cutting edge becomes mundane in 50 years. Calculus was at one time very advanced, and only the most educated understood it
My prediction is that, unlike calculus, design patterns and OOP will not stand the test of time. After an initial blossoming of creativity in the middle of the last century, we are in the dark ages of software engineering right now, complete with the inquisition, crusades, and black death. A century from now, people will look back on OOP and design patterns and think of them as being as ridiculous as Ptolemy's epicycles. -
Re:Why the IAFC is against the change
Just like how everybody laughs at our school systems due to the fact that zero of the American school systems teach any foreign languages until high school On the off chance you're just misinformed and would like to learn, here's some concrete proof that you're very wrong. Here is a listing of all Foreign Language Education programs in the state of Tennessee. I happen to know the professor whose site this comes from, this list is updated regularly as she receives information on changes/additions. From that you can see that we're so backwards here in Tennessee that we even have a few pre-Kindegarten foreign language programs in the state. Some areas have foreign language classes K-12.
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Re:Only got to page 2
Found him... The Escapist is created and published by the Themis Group (http://www.themis-group.com/ which has an office in Durham, NC.
Henry Maxwell Steele ( http://www.lib.utk.edu/refs/tnauthors/authors/stee le-m.html ) lives in Chapel Hill, NC, which is close enough to Durham to be considered "hugging" it. Apparently, 80 year olds speak in the 3rd person. -
Interium solution?Every time I have to deal with a PC problem at work, I just can't help but think that the IT department either gave up on getting users to learn anything about PCs, or they just like having complete power over the great unwashed who just use computers (my opinion changes from day to day). The sad thing is MS just feeds this demand for central contol in the workplace, but in a random way. The best example is the fact that I cannot set my clock, which is usually off by a minute or more, but if IT wants to do an upgrade they have to blast out emails telling users not to turn off their PCs on date X.
This seems to be the best solution for the office of the future, at least for as long as people don't know anything about computers. It's a good thing people don't drive as bad as they use computers... Oh, nevermind.
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List of limitations you've built into your MAN
Fix all those, and you'll have invented IPv6
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Re:Problem in America... BUT
Those English-written articles are of course giving you the standard English pronunciation. I dont see a problem with that -- you're entitled to pronounce foreign names according to the rules of your language, just like you don't call Paris "Pah-hee" like the French do, or Munich "Mewn-shen" like the Germans (man, were those crappy approximations or what).
However, if you are interested in the proper pronunciation of Zeus: the "e" sounds like the "a" in "bay", the "u" sounds like the "oo" in "food".
How to assess this? Look up the Greek spelling in Wikipedia: Zeus article and then this Ancient Greek pronunciation table.
Incidentally, the Ancient Greek pronunciation is exactly the same as we pronounce "Zeus" in my native language (Portuguese), and I assume that's how it is pronounced in German as well (because following strict German rules, Zeus would be pronounced "Tzoyce", as in "Joyce" with a "Tz").
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More obvious linksFor those wanting to know how the figures are calculated, or wanting to calculate them for their own machine, the following links will be helpful:
- High Performance Linpack (Requires MPI and either BLAS or VSIPL)
- High Performance Computing Challenge - the ultimate in stress-testing software
Dependencies:
- LAMPI - MPI from the Government's laboratories at Los Alamos
- MPICH - another version of MPI
- ATLAS - a portable version of BLAS
- VSIPL - a heavy number-crunching image processing package
I doubt many Slashdotter machines will do well against the top 500, but it might be fun to do our own "top 500" (for sheer geek value and bragging rights). - High Performance Linpack (Requires MPI and either BLAS or VSIPL)
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DVORAK and VII tried the switch myself, and found it impossible to use vi. I'm sorry, but no matter it doesn't matter how good your keyboard layout is, it's worthless if I can't use vi. Using the HJKL keys for cursor navigation was horrible!
While I did start programming at an early age, I only really got good at it in college while using a DEC VT 4x0. Man did I love those keyboards. The picture linked is a little different from the one I used, though --- the ESC key was where F11 is. That made vi awesome to use as both hands were very useful. Plus, the fact that the CTRL and SHIFT keys were farther to the left really reduced stress on the left hand.
I bought a VT for $20 at an acution and loved using it for programming. When the monitor ate itself, I held a funeral for my VT. *sniff*.
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Re:minimum mass
The correct formula is Fg = G((m1*m2)/(r^2))
Using Google to come up with necessary constants gives me:
((6.67300 × 10E-11) * (7.5 * 5.97200E24)) / ((2 * 12 756 300)^2)
(I used a theoretical 1 kilogram test mass, at the planet's surface, to simplify things.) ...which Google says is approximately 45.92 N. A one kilogram mass on Earth should exert a downward force due to gravity of 9.8 N if I remember my physics classes correctly.
So, call it about 4.7 times the gravity of Earth. Life? Possibly - but I sure as hell wouldn't want to move there.
--Ender -
The Truth about Mac OS X here
I found this great article here. Read this carefully before you thing about trying OS-X.
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Re:Has the prior digicam hack...
I've gotten feedback from a couple of photography teachers who use it for teaching kids. I have no idea how much this has impacted sales, but I've seen articles in popsci and pc world, so it has gotten out to the public. Next to teaching, my personal favorite use has been the guys who launched one in a balloon to 52,000 feet (previously mentioned on slashdot)
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Re:The school lunch system is broken
Don't you think you're better off with smarter neighbors than dumb ones?
My neighbors are mostly unemployed drug-addicts. I'd wager 90% of them went through the same compulsory education that I did.
I work on computers for a living, because I paid attention when I was taught to use computers in school. My neighbors sell crack for a living, because they're too dumb to understand computers so they instead paid attention to how to make money without being very intelligent.
I can't see how basic education has benefitted them. These people would be better-off had they been taught farming or welding and pointed towards a $25k/yr job instead of grammar and mathematics and driven to give up on participating in the modern economy.
Clearly the educational system in the US has failed us both. Me, because I had to go to school with people who were not motivated or capable of learning what I was. And them, because schooling gave them no other choice but to become the types of people that tax society rather than contribute to it, by wasting their formative years indoctrinating them with knowledge they most likely never will find a use for.
Now I'm going to have to make this anonymous, because it's kind of a rant... -
Re:Let me tell youNAT am wonderful
Sadly not - here's just one brief list of things that NAT break
I can think of other things too, although I do admit that things like Skype have successfully shown that NAT-punching works simply and fairly reliably.
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Re:Does this mean -
Don't worry about being off topic, once the
/. post leaves the front page, nobody else but us cares :-)
The Desktop App example is actually really straightforward: the delays in using Java are immediately visible to the user, and immediately comparable to C/C++ desktop apps. Delays imposed by java on the server side are less visible; as they can only be seen indirectly by a client app (and web browsers are C/C++!), and there aren't many comparable C/C++ apps on the server side.
And, btw, the document you linked to before was all scientific number-crunching. Something that wouldn't run as a server app. And I did read through the source of that, they're reasonably close implementations with each other, in a sec I'll describe why C/C++ is still going to be faster in a production environment (even with the same number-crunching code!). See next paragraph.
As for the intuition claims, what happens when you feed some profiling data back into the compiler (which the better ones accept) ? Any (good) C/C++ app development house will have automated tests running, which provide gobs of good profiling data. And again, a compiler back-end can optimize more aggressively than a JVM can, as it has high-level knowledge of the system (e.g. the source code) vs only the low-level knowledge a JVM has (bytecode only). Not to mention that the low-level implementation of the intermediate representation can be made highly compatible with the target's architecture, vs having one imposed from Sun (which, btw, was made for interpretation, not recompilation, compare with .Net's CLR which was).
And I was being nice about GC, and I'll be nice again. I'll save the debugging arguments for another day -- java programmers tend to fear problems solved in C++ quite easily. Btw, the arguments for JIT are usually similar for GC: in the "big picture" (e.g. a fantasy land where I can claim whatever I want), the overhead is nothing compared to code that we don't actually talk about.
And some more niceness: it's easier to tweak out Java code's performance: the JVM does most of the heavy lifting for you. Java's often easier to develop for (unless you use the libraries too heavily, they're mostly shit), and there are many areas where the dev effort/speed trade off favors java over C/C++. Java has a richer runtime with some nice parts in there (reflection comes to mind).
However, the claim that Java can be faster than C/C++, when good people are put on both side, is false. A C/C++ compiler simply has more knowledge of the system being compiled (the source text vs java bytecode), essentially unlimited time to optimize it (for an extreme case, check out http://www.cs.utk.edu/~rwhaley/papers/icpp05_8.ps ), and full freedom for transformations (a C/C++ compiler, knowing what you originally asked for in the source code, can generate anything it wants that fills your request; a JVM's JIT can only guess at what your source wanted from the bytecode it has to work with, limited to the strict letter of the law given by the bytecode). The paper you listed was an honest attempt at comparison, but GCC isn't optimal on many platforms, most notably intel or ppc.
This is a fair set of tradeoffs; don't let the marketing people and the kool-aide drinkers tell you different. -
In other news
this guy seemed to be a bit skeptical before launch.
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Compared with Google Maps
This was a fun hunt...
Compare:
http://sunsite.utk.edu/~mcoffey/ux-1/ballooncam/20 .jpg
with:
http://maps.google.com/maps?ll=35.621495,-84.73656 2&spn=0.029655,0.029697&t=k&hl=en
Also
http://sunsite.utk.edu/~mcoffey/ux-1/ballooncam/18 .jpg with http://maps.google.com/maps?ll=35.600982,-84.77750 3&spn=0.029655,0.029697&t=k&hl=en -
Compared with Google Maps
This was a fun hunt...
Compare:
http://sunsite.utk.edu/~mcoffey/ux-1/ballooncam/20 .jpg
with:
http://maps.google.com/maps?ll=35.621495,-84.73656 2&spn=0.029655,0.029697&t=k&hl=en
Also
http://sunsite.utk.edu/~mcoffey/ux-1/ballooncam/18 .jpg with http://maps.google.com/maps?ll=35.600982,-84.77750 3&spn=0.029655,0.029697&t=k&hl=en -
Re:Disorganized? Us?
This picture from the balloons payload camera says it all...
confused -
Re:Adaptation vs Evolution
I'm not sure you know exactly what you are speaking about and your argument seems to have contradictions. I mean this in a constructive way and I apologize if it seems to be harsh.
For example, you say that you and your wife are heterozygous for a gene, that is, you express one phenotype, but also carry the gene for the other. If your child has the recessive allele from both you and your wife, by definition, that child will have a phenotype that neither you nor your wife have (imcomplete dominance and other caveats not withstanding).
Second, using the term "information" is vague. I think you mean genetic diversity, but I'm not sure. Evolution is a change in allele frequency, or the realtive proportion of a certain genetic form in a population thus evolution occurs with populations. I think the parent poster was using evolution correctly in that sense. The definintion of adaptation (according to https://notes.utk.edu/bio/greenberg.nsf/0/3ee9cccd 7c64bffd85256cff0061f4d7?OpenDocument/)
requires that "traits persist because they contribute to fitness" and I fail to see how your example of the dogs is adaptation, because there is no gain in fitness, only "look" and I don't understand how genetic information is lost. Only 50% of each parent's genome is passed on, but sometimes there are new combinations of genes. By your definitions, I don't know how to interprit this.
Also, why do you think that evolution requires "information" to be added. There are incredible pressures for efficiency (in the long term and overall, within populations). Vestigal structures and genes are often lost, and this is one example of evolution. For example, bacteria probably used to have introns (non-coding dna within genes), but these were lost. The evidence for this is that both eukaryotes and Archebacteria (spelling?), which are prokaryotes, have introns, but the bulk of prokaryotes (non-Archebacteria and I forget the name... Eubacteria maybe?) do not have introns. By most definitions, this is evolution.
There are numerous theories in evolution as to what is the cause of natural selection, that is whether most mutations are fixed in populations randomly or they actually have measurable fitness differences. I like to think it is determinisitic, but this isn't necessarily true and many intelligent people put forth arguments too complicated for a layman like me to understand, but you should consider both possibilities. Regardless, changing the proportions is evolution, and it can go one way and come back (as the peppercorn moth or peppermoth example shows). Using terms like gain or loss of information is complicated and leads to thought problems like, "well is it gain of information if you lose vestigal or non-functional genes?" What about inheriting 2 recessive genes as you allude to? Ok you lose 2 dominant genes, but now you gain a phenotype that was not present in the parents and perhaps had never been expressed!
I will grant you that loss of function mutations are both more common and, in a certain sense, "easier" than gain of funtion mutations. However, both are evolution. Anyway, I think the parent poster's main point was that evolution did not require isolation. This is a critcal point. Secondly, the parent poster hinted at what evolutionary biologists call "punctuated equilibria." This means that evolution is slow, but goes through rapid phases when the environment changes quickly. This could be resistance to disease or any number of examples. It seems as though the environment is changing more rapidly currently than 2000-5000 years ago, but maybe i'm biased or a timest. If I'm neither, it may suggest that evolution is occuring more rapidly now. -
Re:Doesn't Java fix this?Why does java not do hard core Maths?
You may want to look at the following articles:
http://www.cs.utk.edu/~dongarra/lyon2002/Pozo.ppt
http://www.ukhec.ac.uk/publications/tw/hpcjava.pd
f
From these articles there is a small performance gap, but it doesn't seem that great. -
jgraph
jgraph is quite nice. It does most of the same things as gnuplot, and is (in my opinion) a bit easier to use.
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Re:I saw this on the news.
Tetrachromats are women who have four types of color sensors in their eyes. Apparently the gene for cone development is encoded on the branch of the X chromosome that is missing in the Y chromosome. Thus women (XX) have the potential to be tetrachromatic, whereas men (XY) do not.
Slashdot has had at least one story on it. -
hmmm...
Why not have the camera in/on a pole, moving back and forth continuously at very high speed, and not processing any input that it gets while moving backwards?
http://csep10.phys.utk.edu/astr162/lect/light/spec trum.html has the chart from which I'm making a half-educated guess, with some quick math and fading memories of high school physics, that you would need to move the camera forward about 3/4 the speed of light to make an almost-visible infrared wave appear purplish (almost ultraviolet) to your camera, and >140x the speed of light to make an almost-microwave infrared wave appear reddish.
Off-topic: I love the way this plays on guys' fantasies. Very creepy and disturbing, what with actually putting nipples on and all, and also for those who hide non-body parts (drugs, wires, weapons, etc.) taped to their chest or some other "concealed" part of their body. Maybe IR-blocking clothing will be big business when word gets out... -
Re:Models, shmodels.
By the way, how do you expect magnetic reversals to impact climate? I don't know of any theory that it would matter.
When the magnetic field is in 'mid-phase' or lower than average, we have don't the protection from Sol radiation that we normally enjoy today.
Core samples show that our magnetic field has been reducing for quite a while and has also switched north and south numerous times in the past.
Without shielding from Sol's direct radiation, all sort of 'not so nice' things are likely to happen. Here are some links about our 'flakey' shielding from Sol: (some people see it as the Northern Lights) It's what deflects most dangerous Sol radiation:
Nova
Wikipedia
About the field
More stuff
Changes in that shielding will directly change our climate. After all, if the Earth is unprotected for a few days, things will heat up quite a bit unexpectedly. (Not to mention the damage to life forms without protection from that sort of intense radiation) -
Re:Some Thoughts
First of all I want to say I think it is completly possible to make a processor with 8APUs and so forth.
Check.For starters PowerPC chips already have several seperate execution units on them, and I think they use fewer transitors than intel chips.
Multiple function units on a chip is not the same thing as the 8 APUs of the Cell. First off, there's no indication whatsoever that this is a single-chip architecture. Even if it is a single chip solution, the coupling of a superscalar's function units to the rest of the architecture is extremely strong.The Cell architecture is much more loosely coupled, which could be both it's greatest strength and biggest weakness. It's a very different kind of programming model. If the Cell designers really expect developers to code to the metal, they are in for a surprise. Even the most advanced HPC shops today (i.e. government labs, NSA, etc.) are sick of hand-optimizing code. That's why we have programs like DARPA's HPCS. The software component (compilers, debuggers, perforance analyzers, etc.) is at least as important as the underlying speed of the hardware. Usability is king these days. For the Cell to compete in the HPC market, it must have parallelizing and multithreading compilers.
I find the claim that the Cell will work optimally in all configurations from the PDA to a networked cluster to be dubious at best and patently false at worst. The differences in network latency alone will require radically different software solutions in these two environments. Comparing a cluster of Cell computers using ethernet (even 10G) to a Cray network is ludicrous. GFLOPS ain't the whole story. The Cell may dominate the Top 500 but that's almost universally recognized by HPC experts as next to useless. It's great for marketing and gloating point numbers but I'd like to see how it does on HPC Challenge.
To get a feel for this, look at the HPC Challenge results and compare the Cray Alpha (T3E) to the Dalco Opteron (cluster). Then compare the Dalco to the Cray Opteron (XD1). Then compare the T3E to the Cray X1 and NEC SX-6. Then look at the clock speeds of all the machines.
Moreover, a huge chunk of the transitor budget goes to doing things like cache consistancy or complicated instruction prediction which is probably not used on the much simpler APUs.
Not true. By far the biggest chunk of the transitor budget goes to the cache itself. Predication is relatively cheap compared to full-out dynamic branch prediction. Cell has apparently eliminated the cache which would make room for lots of processing bits. However, I'll note that contrary to what is implied in the article, the newest Cray systems, including the vector machines, all have multiple levels of cache on them. Latency and locality do matter, even in large-scale vector codes.And finally, just because something is vector doesn't mean it's a vector supercomputer. There's a reason NEC and Cray blow SSE/Altivec out of the water and it's not just vector length. It's the whole package of vector ISAs designed for high performance codes (not just pushing polygons), enormous memory and network bandwidth and compilers that know how to make use of it.
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Supernova 1987A
Hubble has been crucial in imaging Supernova 1987A. We have an astonishing volume of data from the Hubble as we follow the sequence as this progresses in the Greater Magellenic Cloud. If Hubble is lost without any replacement, we will lose a rare opportunity to image a supernova this close.
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Re:Dark Fibre (Fiber) defined.
Damn. I was hoping it was fibre made out of dark matter. That sounded much more interesting.
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If torrent is too slow...
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
I originally got the video using BT. I have left my connection open for a couple of hours to continue supplying the video, but my total uploads never get over 2.4 Mbps which is disgraceful on a campus connected at OC-12 (622 Mbps). Using LoDN or LoRS should get I2 users the file at 30-80 Mbps if not higher (on GigE connected machines).
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If torrent is too slow...
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
I originally got the video using BT. I have left my connection open for a couple of hours to continue supplying the video, but my total uploads never get over 2.4 Mbps which is disgraceful on a campus connected at OC-12 (622 Mbps). Using LoDN or LoRS should get I2 users the file at 30-80 Mbps if not higher (on GigE connected machines).
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If torrent is too slow...
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
I originally got the video using BT. I have left my connection open for a couple of hours to continue supplying the video, but my total uploads never get over 2.4 Mbps which is disgraceful on a campus connected at OC-12 (622 Mbps). Using LoDN or LoRS should get I2 users the file at 30-80 Mbps if not higher (on GigE connected machines).
-
If torrent is too slow...
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
I originally got the video using BT. I have left my connection open for a couple of hours to continue supplying the video, but my total uploads never get over 2.4 Mbps which is disgraceful on a campus connected at OC-12 (622 Mbps). Using LoDN or LoRS should get I2 users the file at 30-80 Mbps if not higher (on GigE connected machines).
-
If torrent is too slow...
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
I originally got the video using BT. I have left my connection open for a couple of hours to continue supplying the video, but my total uploads never get over 2.4 Mbps which is disgraceful on a campus connected at OC-12 (622 Mbps). Using LoDN or LoRS should get I2 users the file at 30-80 Mbps if not higher (on GigE connected machines).
-
Gate's demo video for Internet2 users
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
-
Gate's demo video for Internet2 users
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
-
Gate's demo video for Internet2 users
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
-
Gate's demo video for Internet2 users
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
-
Gate's demo video for Internet2 users
If you are on Internet2 (or another fast research network), you can get the video at speeds up to 80 Mbps here which requires Java Web Start to download the LoDN client. If you have a set of LoRS Tools, then you can get the exNode at 2005_0105_ms_ces_300agility.wmv.xnd.
On high-speed networks, set threads to 10 and blocksize to 1 MB. On cable/dsl (you are going to try it even though you are not on Internet2, aren't you), use 3 threads and a blocksize of 512KB. Dial-up users should just click on the link in the above post.
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Re:News Flash: The Sun Emits Radio Waves
Are you sure?
If I recall from college chemistry a few years ago, Microwave radiation was high up on the spectrum scale near Xrays and gamma rays and past UV rays which already can damage DNA.
I think you need to check your facts.
It is you who needs to check the facts. -
Re:Neither of these is that important
What sorry excuse for a college did you go to? I can't imagine any accredited school allowing a program like that.
I took freshman Chem at UTK, and even though it was a pretty standard overcrowded chem class (300 students in a giant lecture hall), with a horribly boring professor who took the slides away before we could finish copying them, we still learned everything we should have in a freshman chem class: atoms, molecules, reactions, electronegativity, nuclear reactions, etc.
Did you even have a lab component to the class? -
Already there
You should see what Micah Beck is doing with IBP. Can anyone say "Distributed PVR?"
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Already there
You should see what Micah Beck is doing with IBP. Can anyone say "Distributed PVR?"
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Re:Missing the problem
The answer is not to 'censor' the 'junk' to 'protect' the unwashed masses by some higher authority (whatever it may be).
Any scientific article in the popular press has to "censor" a lot of material, simply because it would not be understood by the public without hundreds or thousands of pages of background material. Distinguishing between fringe and mainstream theories falls into this category--as a rule it is simply not possible to summarize briefly and comprehensibly the mass of data that lead most scientists to strongly prefer one theory over another. So for most purposes, the best that can be done is to say, "Almost all leading scientists in the field favor theory A" and refer the reader to the scientific literature if they want to understand or critique why this is so.
Concerning the second paragraph, the value of a theory is related to its practicality. How good is it at predicting the future ( future observations of reality)? Futhermore, it is my opinion that theory a) that says the sun orbits earth in an eliptic fashion is equally useless (and wrong) as theory b) that says the earth orbits the sun, describing a circle.
Actually, neither theory used ellipses. Ptolemaic theory used a complicated and arbitrary system of circular orbits running around other circular orbits, with the sun in the middle. It was so complex that it could be made to match virtually any observation. The Copernican system on the other hand, was so simple that the only way for Kepler to bring it into better correspondence with observations was to give up on the circular orbits, even though Kepler hated ellipses, regarding them as imperfect circles. So in that sense, Copernican theory was better, because it was capable of leading scientists to a better understanding, while Ptolemaic theory was a blind alley.