1887 posts • joined Tuesday 24th April 2007 14:31 GMT
My experience with ScaleMP is
not very good. I tested software which ran beautifully on a 24 core (6 quad-core) opterons (18-22 x speed-up) crunching through multi-scale analysis of a 1.2 gigapixel image in 60 seconds. On a 64 core (4x 16 cores if I am right) ScaleMP box performance was DISMAL. As more threads are added, the performance tends to drop severely. On a single thread I would get a timing of say 60 seconds for a smallish data set, on 2 threads it took anything up to 5 minutes. The scheduler NEVER puts two threads of the same program on a single board, but scatters them far and wide. You can only gain speed up on these boxes if you have many light-weight processes which do not need to share much memory. Did we not have clusters for that?
Actually, in most embedded systems
you learn to program with energy efficiency in mind. Talk to guys doing sensor-network coding, they design communication protocols specifically with ULTRA low energy consumption in mind.
Other than that, it is just a case of efficient coding. If I can reduce the number of instructions by an order, I save energy by the same order. Lazy programming and reliance of Moore's law to do YOUR work of getting things running quickly causes these problems.
After all, we now assume you need the computing power of a Cray Y-MP to edit letters or do some spreadsheet work effectively.
A patent on placement of objects on a screen?
only in the US
Self targeting =
shooting yourself in the foot? (if written in C of course)
Ah, the mythology of data mining
"If we have enough data, the problem will be solved"
You want information, not more data. As more data are added, the problems of finding what you need get harder and harder. It's like Pratchett's omniscope: becase it can show you everything, it is practically useless at showing anything in particular.
THINK before you add more sensors and more data.
It depends on humidity
I experienced near 50 degrees C in the Negev desert, but because the humidity was in single figures, your body can get rid of excess heat through sweating. If the humidity is too high, you cannot release the excess heat, your body temperature exceeds 42 deg and you die.
Divers in certain areas carry alarms to tell them the water is above 37 deg C for this reason
Must be a candidate, unless he had kids (for everyone concerned, I sincerely hope not)
Wasn't it rancid
when it was first released?
I remember teaching web design at that time, and reading up on all the vitriol spewed over the product by web designers right then (and on IE5 as I recall). Some students wanting to create really fancy designs had a seriously hard time getting it to render reasonably on a wide range of browsers.
At least MS-Oz is being candid about the product's quality, albeit rather late.
Typical behaviour for adolescents then?
destructive through and through! stars, kids, they are all the same
Patent != innovation
I found one patent on making a blinking cursor by repeatedly XORing the cursor content with current screen content (DUH). In the US this is more than innovative enough to get a patent. The USPTO does a disastrously bad job of checking for prior art, leaving it to courts to find out which patents are innovative, and which not.
The REST mass of the protons was way smaller than the B+ (disappointing grade to some ;-) )
The sum of the masses they had in the lab frame of reference was as high or higher than the B+.
Great fun nonetheless
Ye cannae break the laws of physics capt'n II
No Nokia, you cannot take deep-space photos with your camera phone, and you cannot replace a 400 mm F5.6 APO telephoto with a lens that fits into a thimble.
The guy probably believes the image enhancement effects in CSI.
I get so tired of this sort of idiots (highly paid at that). For those still doubting:
The first issue is all about photon counts. The noise in an image is determined (apart from detector noise) most fundamentally by photon noise. Because emission and detection of photons is a random process, the noise is equal to the square root of the number of photons detected. So if a pixel captures 100 photons, the expected noise is 10. If you capture 10000 photons the noise is 100, but the signal-to-noise ratio (S/N) is 10 in the first case and 100 in the latter. S/N is very important in image quality. This is why astronomers want BIG scopes, because doubling the diameter quadruples the amount of light, and doubles S/N.
No matter of post-processing can alter these facts. I teach computer vision and image processing at the University of Groningen, and have worked quite a bit on developing ways to counter the effects of noise.
The second issue is resolution: the limit of resolution is determined by the ratio of wavelength to aperture. This is why we are building a synthetic aperture telescope HUNDREDS OF MILES ACROSS for long radio wavelength. There used to be al sorts of wild claims on what deconvolution methods could do, but in the field it is now accepted that whilst you can enhance details that are faint (at the risk of increasing noise) you cannot reconstruct information that has simply been lost at the aperture of the lens.
Yes the do have to be large
Diffraction only quits being a problem in the near field (as in NSOM (Near-field Scanning Optical Microscopes)). Otherwise -> big surface area = better S/N + better resolution (if properly corrected by whatever means). Improvements can be made in weight/bulk, but aperture is irreplaceable.
Ye cannae break the laws of physics capt'n
A phased array design you seem to be proposing works fine in radio for three reasons: (i) wavelengths are long so mechanical tolerances are fairly relaxed, (ii) photon counts are HIGH, due to low energy per photon, and (iii) phase can be measured. This allows digital correlation of the signals. All three properties are lost in visual range. Optical heterodyning is very difficult and requires very bulky equipment. Getting solid optics down to the tolerances need is hard, fluid is worse. If the ESO Very Large Telescope in finds it hard to do, I do not think a portable version will be around soon
Ig Nobel prize!!
worthy at least
C++ initially was cross compiled.
Methinks there is a bit of a contradiction in your argument (word used without prejudice)
As a Yurpean
and a developer, I would love to see WebOS take off. I am probably not going to get my hands on a WebOS phone any time soon, more's the pity. If WebOS fails, it is due to business decisions and not technical merit (remember Betamax?), Nokia buying Palm could prevent that happening.
Please do not speak for all Europeans, and if you feel an irresistible urge to do so, please try to sound more sensible
VMs and garbage collection get in the way
of speed, but then speed is not always needed. Very often programs spend most time waiting for user responses. Java is OK then. Just do not start teaching in Java, as the kids never learn how to TIDY UP THEIR MESS!!! Once they can program properly in C (or even Pascal), and know how linked list work from the inside out, they can be allowed to use prefab code available in Java.
When processing gigapixel and terapixel images, I really need to go to C(++) or similar. Java actually is not the worst: scripting languages are the real killers. I have seen some dismal attempts at processing SERIOUS amounts of text in python. What python does in days C does in minutes. Result: a 16 core machine is constantly chugging away with 16 python jobs which could have been finished WEEKS ago, meaning I cannot test my efficient parallel C-code on this machine (BLEH).
Python and the like are great for prototyping and stringing together bits of compiled C code in a flexible way, just do not process ARRAYs of real data.
But I rather like
There have been some remarks about the use of it all
We could equally say: Why should anyone pay millions for a Picasso, Rembrandt or Van Gogh? Why should anyone pay a composer, or musician, or a fiction writer?
Answers: because we are human beings. We just like doing certain things because of curiosity or because we want to move our fellow humans emotionally. Most of all we make music, paintings sculptures and do science because it is fun, or because we could not imagine us being us WITHOUT doing it.
In the very long run, if we are to survive, we will need to travel vast distances in space. Better understanding of physics is essential to this venture. However, in my opinion, we will only be worth saving in the long run if we do not lose our ability to do things out of curiosity, creativity and compassion, and without looking at the bottom line all the time.
No beancounter can ever put a value on the joy of doing science
when will they start
colliding aircraft carriers?
but I would be shocked if someone put stuff like this on my phone. Not because I would be shocked by the pics themselves (necessarily), but by the fact that someone put unwanted stuff on my phone AT ALL. By the same token, they might have enlisted you for all sorts of nasty (costly) subscriptions to unwanted services, or all sorts of spyware.
I am afraid I must resort to the use of the FAIL icon for the first time
The moons of Jupiter spend only a short amount of time in the shadow of the planet. The more distant the orbit, the smaller the fraction of time in the shadow. It would have some effect on th etemperature, but not life-threateningly so
I am removing Ubuntu from my laptop. The last straw was that it froze four times in one evening, only "responding" to me yanking both the power cord and the battery from the machine. It has proven an unstable piece of fetid dingo's kidneys. OpenSUSE 11.2 works fine on my desktop, will now retake my laptop.
Integrating Twitter and facebook with an OS? NO THANK YOU. Never use these things, unlikely to change in the short term. This is application-level stuff, and I assume Canonical will actually integrate between applications rather than at the OS level.
Three, at least actually
It was a three-judge panel after all. The parents too exhibited intelligence in fighting this.
GPL gives you the right to use stuff FREE
provided you return the favour. Your get it FREE, so logically you are not entitled to any refund. You can distribute anything anywhere, provided you release your source code.
With Apple you pay, you invest hundreds of hours of work, you might end up not being able to sell or even distribute ANYTHING at a whim, with no chance of recompense. I would not waste ANY time on that.
Because it's very different from Deimos
Most moons are solid, this one is not. People used to think this tiny moon was a captured asteroid, they were apparently wrong.
Not perhaps the greatest excitement, but still interesting
Or try processing
100 Mpixel to 1Gpixel images on a smartphone. Do that quite regularly now on my desktop
It is simple
They do not visit us because we play cricket!
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