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From the blog post: "Instead, they [children] are conscious from the get-go".

God, not so fast! Could you define this "get-go", please? Is it when a sperm cell fertilizes an egg cell? Or some time later? And if some time later then when exactly? At 2 weeks? 3? 4? 5? 20? 40?

Personally I'm open to nuclear power, where it makes sense - and there are certainly sites where it makes the most sense. However I disagree that it's always the best alternative, and especially that any other option is "suicide".

For one, nuclear isn't as cheap as you seem to think. According to the EIA, (onshore) wind and solar PV both have significantly lower LCOE than nuclear, at $58.5 and $74.2 per MWh, vs $99.7 for nuclear. That's after accounting for their lower capacity factors, and before any tax credits. Wind and solar are cheaper to build, generally cheaper to maintain, and have zero ongoing fuel costs.

And while I agree that modern nuclear has a very low chance of dangerous failure, it's still non-zero, and you have to multiply that chance by the economic costs of consequences, which can be very high. Failure costs aren't factored in to the above numbers, but they can't be dismissed either. Despite that, I think nuclear should still be considered, particularly for more northern sites where solar is less effective and available wind may not be enough.

I'm guessing your objection to solar & wind is the "baseload" concern, where low capacity factors require alternate sources. This isn't a new issue for the energy industry (nothing has a 100% capacity factor), and is traditionally solved by distributing the load over multiple plants. A number of studies show that reliable power is certainly feasible with renewables too. For example, with widely-distributed wind farms, local variations can be spread out over the larger grid, and excess solar can be stored with pumped hydro (where available) or any of a number of commercially-available grid storage technologies, including reflow batteries (which can be easily scaled to almost any desired storage capacity). During the transition (which would likely take decades), existing gas turbines can help cover any shortfalls. I also note that geothermal plants are particularly interesting here, as not only do they have a capacity factor even better than nuclear's, they also have the cheapest LCOE of all.

http://www.engineering.unsw.ed... http://www.cqc2t.org/research And the patent docs https://register.epo.org/appli...

And did you seriously just reference John Lott, and then use the phrase "well researched" in the same sentence? You dumbass: That's like citing Senator Inhofe as your source for global warming data.

If you would reference Lott, you should a bit about him first:

From ( http://www.armedwithreason.com... ):

Lott’s work is filled with bizarre results that are inconsistent with established facts in criminology.

According to Lott’s data, for example, rural areas are more dangerous than cities. FBI data clearly shows this is not the case. Lott’s model finds that both increasing unemployment and decreasing the number of middle-aged and elderly black women would produce substantial decreases in the homicide rate, conclusions that are so bizarre that they should cast doubt on the entire study.

From ( http://www.cse.unsw.edu.au/~la... , basically 47 pages of why "correlation is not causation"):

Only 20% of permits were issued to women, but the male and female homi-
cides rate went down by the same amount and the reduction in the rape rate
was similar to the decrease in assaults. Lott speculates that guns are four
times as effective for females. While this is not impossible it seems more
likely that the decreases were caused by some other factor that applied to
males and females equally.

Or from my favorite:

The empirical studies of right-to-carry laws preceding Lott and Mustard’s study may be flawed,2" but if these studies have any value, they suggest that right-to-carry laws and high gun ownership levels either have no significant effect on crime or else increase it Both Ludwig and Black and Nagin conclude that no credible empirical evidence supports the judgment that right-to-carry laws deter crime. At this point, there is essentially no reason for an intelligent consumer of social science research to accept the Lott and Mustard findings.

Of course the right-to-carry cure for violence worked for the Hatfields and McCoys. It worked for Bernhard Goetz. It worked on the American frontier. It is being copied in Rwanda today. According to John Lott and David Mustard, right-to-carry can work for us too.

http://scholar.valpo.edu/cgi/v...

Although let's be honest, you didn't look into shit, and you never actually read Lott's research either. (Helpful link: http://www.johnlott.org/ )

You just picked up the name from the NRA or some other group of idiots.

http://theconversation.com/baseload-power-is-a-myth-even-intermittent-renewables-will-work-13210

http://www.ceem.unsw.edu.au/sites/default/files/uploads/publications/MarkBaseloadFallacyANZSEE.pdf

http://www.skepticalscience.com/print.php?r=374

http://bze.org.au/media/newswire/living-green-power-renewables-131007 (and that's from the energy market!)

http://cleantechnica.com/2014/08/08/rmi-blows-lid-baseload-power-myth-video/

slashdot today!? ... difference between North and South

There is a distinction between the two, of course, but it is without difference to the topic of this thread. Both ice-caps were supposed to shrink (with dire consequences for the rest of the world, of course).

One expedition set out to measure the loss of the ice, found itself stuck in it — not that it changed the leading professor's opinion about the global warming...

The Antarctic sea ice extent was not and is not projected to shrink in the near term. It was expected to expand as a result of the influx of fresh water from increasing land ice melt. As the planet continues to warm it will reach a point where the ice extent will start shrinking again (as the 0C starts pushing further south), but that isn't projected to happen until later this century.

slashdot today!? ... difference between North and South

There is a distinction between the two, of course, but it is without difference to the topic of this thread. Both ice-caps were supposed to shrink (with dire consequences for the rest of the world, of course).

One expedition set out to measure the loss of the ice, found itself stuck in it — not that it changed the leading professor's opinion about the global warming...

Particles can't really be two places at once.

And here you are completely wrong. Finiteness of the universe disagrees.

The double slit experiment mentioned by another poster shows this is the correct interpretation too. As you can see from the photos on Wikipedia, when single particles are allowed thru, we see only single points on the detector. It is only when a flood of electrons are allowed that we see an interference pattern similar to that of a wave

You are wrong again. Stop. Double slit experiment has been duplicated using *individual photons*. Yes, one photon fired at detector at a time. ONE. No more, just ONE. After waiting sufficiently long, interference pattern was produced on the detector. The photon appears to have interfered with itself.

http://www.animations.physics....

Because artificial limitations are useless? What if we find that space isn't continuous, will you call for abolishing real numbers or something?

If you read some of N. J. Wildberger's writings, which go from personal views up to entire alternative Mathematical foundations, you will find an enthusiastic and competent supporter of the constructivist / computational / anti-infinity viewpoint.

His book on Rational Trigonometry is particularly interesting, as well as his papers and random writings. His position against real numbers, in the preface to the book and also in one of his online PDFs, is very convincing. His rational trigonometry and universal geometry formulas and theorems are solid (not no mention quite useful in my programming job.)

Overall he has changed the way I think about infinity and uncomputable mathematical entities. I would say he definitely has a point. He has a wealth of Youtube sessions too, where he teaches a great part of Maths, including calculus, without touching infinite sets, "real" numbers and other troublesome fabrications.

So, in general, through all the high school programs that UNSW has available, I'd say it attracts the best students. It just so happens that I know a decent proportion of the students that participated in this competition and I know that they had a keen interest in computer science; so these are the better, more experienced, more enthusiastic students we're talking about here.

Also, UNSW's main security course, COMP9447, is cited as being a good course by people I know who've done it and is very popular amongst the students: They extended the enrollment in the course for this semester at least once (not sure by how much) and there are still many students who missed out.

I take it you think these requirements are really unreasonable, but to me they seem reasonable.

Really? 16 years of experience? And note that's experience working under a P.E. who will sign off on it, not just any old experience. Plus references from 9 people including 5 P.E.? I don't think I even know 5 P.E.s. And I have almost 20 years of experience.

Know how many Professional Software Engineers there are in all of Texas? 78, of whom 63 are active. That's how onerous the process is.

Note that the ACM and the IEEE once had a joint project to develop professional standards for engineers. The ACM pulled out when it became clear the IEEE was going down the P.E. path.

First you must measure how many decibel of attenuation you need. For this you need a sound level meter: If you don't have one at hand, a microphone + PC sound card + Audacity can be used as well (many apps for Android/Ipad are also available for this). Measure two sound spectra at your location: the first one with traffic noise present, the second one when you feel that background noise level is comfortable for you. The difference between the two spectra will tell you how much attenuation you need, and which frequencies need to be attenuated more.

Next compare the attenuation offered by each possible solutions (noise attenuationg windows, wall insulation, etc.) against the attenuation you need to achieve. If it isn't enough, move away, otherwise try installing the best solution you can afford.

Noise should be stopped before it enters the walls of your home: Once it is there, it can follow unsuspected paths to reach your ears (pipes, wall joints, etc.). The best way to stop it is to increase the acoustic impedance of external walls and windows.

Attenuation could be increased using viscoelastic materials like rubber: however they are best for attenuating high frequencies.

Not sure where you got that price from.

USGS Minerals Industry Summary - Pumice. That's the bulk price.

There are "Trash Hunter boats that could pick up pumice, but they're not intended for remote open-ocean operations. To collect this stuff, it would take booms and ocean-going tugs or fishing boats to concentrate the floating pumice, a collection vessel to pull it out of the water and screen it, and a bulk freighter to haul it to some customer. It's like cleaning up an oil spill, except that it's a solid. It might be desirable to do this if the mess drifts to a populated area.

Over time, wave action breaks the stuff up, opens the gas pockets that make it float, and it sinks. This takes about a year, so it's not a long term problem. It happens now and then. Known events off Tonga in 1964 and 2002 have been studied. Long-term impact is low; it's hard to tell, a few years later, that it ever happened.

Seeing this article immediately made me think of the Essential Reality P5 Data Glove sitting on my desk. Seems to me that sign-language reading gloves have been around since the early 1990's. Here are a few related links. I'm not sure what is new here that hasn't already been done.

Possibly, but possibly not. For one thing, the attack being shown here is far, far from news. And there are actually tons of ways to build a GPS receiver with the native ability to detect spoofing, and those features are standard for high-risk equipment (like classified stealth drones). But on the other hand, all of the details are classified in some way or another, so it's really hard to know for sure...but I doubt that it was all that simple as the attack shown here.

One simple way of detecting spoofing is by frequency strength. The most basic attack is to impersonate the satellites, and to be strong enough in output that the receiver is sure to pick up your "sats" instead of the real ones. But that typically means you're putting out a WAY stronger signal than you'd normally get from a GPS, and that ends up being a dead giveaway.

For military uses, the open and unencrypted C/A code GPS signal isn't even used; they use the more secure (and originally supposedly more accurate...but not really more accurate) P code signal (which now has a W code overlaid onto it as well). So there are inherent features involved in military GPS that act as anti-spoofing as well.

You should check out Universal Geometry and Rational Trigonometry. By redefining length and angle you can greatly simplify geometry where all problems are solvable by algebra without trig functions. Very cool.

http://web.maths.unsw.edu.au/~norman/YouTube.htm#WildTrig

Can a wind cart travel faster than the wind?

If boats can go faster than the wind, why not a wind cart?

So it should have been made much more clear that this is about down wind. OK. mentioned later, but who reads that far in a summery.

Reminds me of the philosophy department at the University of Sydney which, during the heyday of the student movement split into two departments - General Philosophy (which was run as a little Communist collective, trying to live by the various French poststructuralist and postmodern theorists) and Traditional and Modern Philosophy (which taught mainstream Anglo-American philosophy in a normal way). From an article on the topic:

The Department was fully democratic, with all staff and students having the right to speak and vote on matters of course content, assessment and appointments. Meetings of up to 500 were known, though student apathy kept most down to some 20. Formal exams were eliminated, and in some subjects students assessed themselves.

IIRC, they also ended up assessing political philosophy modules by counting attendance at various political protests. The 'Traditional and Modern' department eventually 'won' in the 90s after poaching various other top professors over, and Sydney has gone back to being a pretty good department.

(When I see people trying to take what works on the Internet and apply it back to offline society, I sort of want to shake them and say "yeah, there's a reason we started doing it this way online - because it's online, duh. The mechanics and economics of it might not really work out in the same way if you are doing it in real life.")

I guess that Sun were just too nice a company to prosper

Well that and they were way over priced ...

Well that and the Open Source Community caught up with them ...

That must be why the Linux kernel has to put an artificial 2 GB limit on the allowable size for a single IO request...

The Linux kernel even today isn't fully 64-bit safe. Solaris was fully 64-bit safe 15 years ago or so.

Yeah, but the big problem is that it doesn't correlate to that analogy- you can't go faster than the wind you're tacking against with a sail

Huh? That's news to all the sailors out there who do routinely sail faster than the wind.

Physics explained here in the "How can boats sail faster than the wind?" section:
http://www.animations.physics.unsw.edu.au/jw/sailing.html

You don't need input energy to maintain your momentum--you only need enough input energy to overcome friction/drag, anything beyond that can accelerate you.

classes such as this one? [university of nsw]

I have a friend who was a tutor for the class, sounded pretty cool and a fun way to burn through some gen-ed requirements.

there are some lecture slides listed here[unsw] if anyone is interested

classes such as this one? [university of nsw]

I have a friend who was a tutor for the class, sounded pretty cool and a fun way to burn through some gen-ed requirements.

there are some lecture slides listed here[unsw] if anyone is interested

I find it striking how much Figure 8 in the PDF, showing the location of single-bit faults, resembles the acoustic power spectrum of something behaving like a closed tube. I see clear odd numbered partials and weak even numbered partials, with a missing fundamental. I would not be surprised if this distribution turns out to be connected to the exact timing of the attacks. Sweeping the timing of the attacks may cause other bits to be affected.

Mal-2

If so if there is enough heat to keep water in its liquid state, there might be enough power to at least energize simple singe cell-type organisms

Don't confuse water that is liquid due to pressure and water that is liquid due to temperature. Not saying that it's too cold for life, I think you can get water to around -20 celcius without freezing if you put enough pressure on it (after that it forms ice-trhee, five etc.

You can get some more info on this here and here.

It's 89 km from Plato - a Chinese-Australian robotic observatory at "Dome A".

That's at 80 deg 22' S 77 deg 21' E and 4093 meters above sea level.

I have to wonder if it's that much better than PLATO that there is a need for 2 observatories 89 km apart.

...Also why do they have to make roads out of them.. where did that come from? Just put them out on land somewhere, you don't have to drive all over them.

This was my first thought too. Making the solar panels into roads (or vice versa) is compounding the problem. Just put the 25,000 mi^2 of solar panels in the middle of the desert and call it even. Adding a layer of glass or some sort of protective surface is going to lessen the efficiency and raise the cost of production and maintenance. I'm all about green energy, but there are better places we could be spending our money and energy.

Back at uni, I did a mini-course on the the Solar Car challenge, because my University made some of the solar panels for the top cars, and we also had a car that entered and did fairly well (for a low budget). One of the things we learned was that solar cells lose efficiency very quickly from a variety of things. The two that most researchers ignored in the lab but mattered in the field was heat and dirt. The cars in the race are washed with cold water thoroughly at every opportunity because colder, cleaner cells are substantially more efficient. Think CPU overclocking - lower temperatures improves things a lot.

Now lets compare this situation to a typical road which is:
a) Blistering hot most days.
b) Really, truly, thoroughly dirty.

Sounds like the perfect place to put an expensive solar cell panel!

Another thing we learned is that a single "test" panel in a lab operates very differently to a bunch of real panels in the field. What a lot of naive researchers miss is that the amount of sunlight over the entire collecting surface in the real-world is not constant. For a one-square-foot panel, it is, but for any significant surface (the size of a car, road, whatever), it won't be. The surface will be curved or partially shadowed. This matters a lot because if you just connect a bunch of cells together, they perform roughly the same as the worst of the lot. If there's a few cells under a shadow, that's drags down the efficiency of the panels receiving sunlight. To efficiently extract energy from a bunch of panels receiving differing amounts of light takes a bunch of expensive power management electronics that can combine the different cell outputs in the right way.

In practice, cells are so expensive that the best place to put them is on huge, flat, orientable panels out in the desert where there's no clouds, no rainfall to cake dirt onto the panels, and they can be oriented to face the sun at all time, like this array in southern California.

Anna Liu, Associate Professor in services engineering at the UNSW School of Computer Science told iTnews she was excited by Cloud Computing as it could potentially enable organisations to "outsource a certain amount of their risks and costs and tap into new economies of scale."

Sounds more like she has a degree in buzzword engineering.

From her homepage at UNSW, it seems to be the creation and study of services but her focus seems to be on cloud computing with the "services" being concentrated on these subjects. While a lot of her about page seems to be buzzwords and journal writing, I really wish they would release their "interoperable service software" and would be interested in seeing their final report for more specific metrics. Her blog doesn't say much about it. I'd give her the benefit of the doubt, she says in the article, "We saw a lot of hype and confusion, and decided to lead a team of researchers and actually get our hands dirty with this stuff." She also said:

Using Google AppEngine, none of your data processing tasks can last any longer than thirty seconds, or it throws an exception back at you. This is very consistent with the Google business model - they want to enable simple web applications to thrive on the Internet. AppEngine is there to enable the rapid development of simple web applications that don't include intense compute at the back end. - Anna Liu

Which I found interesting. Again, kind of hard to judge the merits behind this research without even a brief description of what the services were ... a singular value decomposition service? A return huge data sets from a database table service? A prime factorization service? A file intensive I/O service? I'm also curious as to what hoops one has to jump through to get those interoperable across all three systems ... after all Microsoft is just .NET, right? Is this rewriting something 3 times or making shared objects or what?

Anna Liu, Associate Professor in services engineering at the UNSW School of Computer Science told iTnews she was excited by Cloud Computing as it could potentially enable organisations to "outsource a certain amount of their risks and costs and tap into new economies of scale."

Sounds more like she has a degree in buzzword engineering.

From her homepage at UNSW, it seems to be the creation and study of services but her focus seems to be on cloud computing with the "services" being concentrated on these subjects. While a lot of her about page seems to be buzzwords and journal writing, I really wish they would release their "interoperable service software" and would be interested in seeing their final report for more specific metrics. Her blog doesn't say much about it. I'd give her the benefit of the doubt, she says in the article, "We saw a lot of hype and confusion, and decided to lead a team of researchers and actually get our hands dirty with this stuff." She also said:

Using Google AppEngine, none of your data processing tasks can last any longer than thirty seconds, or it throws an exception back at you. This is very consistent with the Google business model - they want to enable simple web applications to thrive on the Internet. AppEngine is there to enable the rapid development of simple web applications that don't include intense compute at the back end. - Anna Liu

Which I found interesting. Again, kind of hard to judge the merits behind this research without even a brief description of what the services were ... a singular value decomposition service? A return huge data sets from a database table service? A prime factorization service? A file intensive I/O service? I'm also curious as to what hoops one has to jump through to get those interoperable across all three systems ... after all Microsoft is just .NET, right? Is this rewriting something 3 times or making shared objects or what?

Conspiracy theory websites? They're skeptic websites, where they've actually done their research. I suppose that James Randi is now the king of conspiracy theorists? You'll notice with the first one that the website looks skeptically at things like alternative medicines, such as homeopathy, acupuncture, chiropractic, organic, etc... The second one is by this guy http://www.cse.unsw.edu.au/~lambert/ whom is also not a conspiracy theorist, if you actually read what he had said on that page you'd see that he was the one laughing at the conspiracy theorists.

Sails generate lift when sailing close to the wind(i.e. upwind) but that lift isn't going to be directly forwards, so you are right that the keel has to balance that to make the boat go forwards, but you are wrong that the sails don't produce lift. Obviously, sailing downwind is different and you can just have the wind push you.

See http://www.physclips.unsw.edu.au/jw/sailing.html for more.

UltraSparc T2 + Cell SPUs...

All they need now is a language suitable for such a sick practical joke. I suggest this.

Here is a project where Australian design students from College of Fine Arts, University New South Wales and New Zealand pharmacy students researched the Kenyan cultural ways of life and designed soccer uniforms for HIV awareness.

Green apparently is a colour for witches, so green was not used.

More information on the project is here Creative Waves

Disclaimer - I'm a web sys admin for Omnium, the design arm of the endevour.

Like other posters pointed out: you likely don't know what thermodynamics even is. Hint: thermo has something to do with temperature. Thermodynamcs is about entropy and heat not about magnetic fields or electric fields.

Do you? Try googling the next time... some random examples:
http://www.phys.unsw.edu.au/~gary/SM3_7.pdf
http://www.ifw-dresden.de/institutes/iff/research/TMO/Magnetism

Classically thermodynamics was all about heat and temperature and as been developed to accurately describe steam engines. Since then this has evolved and been applied to many other situations. Thermodynamics is about describing macroscopic properties of a large ensemble of particles (this includes photons and such) by their microscopic behaviour. This is not limited to simple mechanical effects like gas molecules bouncing off of each other.

See also: Indian Ocean Dipole.

It's been stuck in the "positive" phase for 3 seasons, which is unprecedented in recent history (past ~100y). The positive phase seems to correspond with warmer western Indian Ocean water. Effects of this phase are stronger monsoons on the Indian subcontinent and deeper droughts in the east.

Here is the site maintained by the team who first described the phenomenon in 1999. It has since been evidenced by historical observations this century and examination of fossil coral. BBC article seems to suggest that there are skeptics in climatology, but I think it's misleading; its existence is non-controversial, only its influence when compared to the ENSO is questioned.

Here is news from UNSW, and here is the abstract of the paper that the popular press is referring to.

Ask Richard Buckland. If you're able to get through to him I think he'd have some great ideas for you, because this very subject is one of his greatest passions.

No thread on teaching programming to kids would be complete without a shout out to him. He has a freakish ability to make the most dry, technical, theoretical computer science topics highly entertaining, engaging and educational. I've been fortunate enough to see him in action a few times, the guy is a brilliantly talented teacher. There's a reason he's been given award after award for the quality of his teaching - he cares, and he's unbelievably good at it.

you use a more than 1 sail to catch the deflected wind. I just googled it and came across this page.

http://www.physclips.unsw.edu.au/jw/sailing.html

Here's another photo minus the huge goggles.

Google, please.

http://www.phys.unsw.edu.au/~jw/superheating.html

That's simply H20 by itself. Pressure + water can also be explosive to the container of the water.

sorry to reply to my own post. I accidentally didn't format the linux MD RAID 10 driver page correctly :

driver page.

Also, it may not have been evident from my post, but this is all through software RAID. It is also my understanding that this RAID 10 mode is less CPU intensive than RAID 5, but this isn't much of an issue with today's fast, multi-core processors.

Just to add a bit of information to this post. I believe the RAID mode this poster is talking about is indeed RAID 10 and not RAID 1+0 or 0+1 -- stripped mirrors or mirrored stripes. This new RAID mode is supported by the linux md driver.

Linux MD RAID 10 driver page.

This RAID mode does not require an even number of discs. My understanding is that writes are much faster with RAID 10 than RAID 5 because parity checks are not necessary. However, this RAID10 mode gives you only half of your total RAID size, and RAID 5 gives you your total RAID size minus one drive in capacity.

Some useful, more detailed (and likely more accurate) information

Some performance comparison results to RAID 5. It would appear that the read performance is close to RAID 0, and the write performance is close to RAID 0 divided by two -- because every write has to be done twice. Furthermore, RAID10 can be more robust for drive failure.

Most of the time, we study real musical instruments, real musicians, the voice and the ear. Some of this is sponsored by companies (instrument makers, a medical device company, a museum), but much of it is curiosity research.

For us, the robot project complements one of our areas in which we study real musicians and how they play. We want to know, in some detail, why a real musician plays better and makes a better sound than a beginner. (Curiosity research, but with an obvious application in music teaching and sometimes instrument design.)

The robot is a tool for testing our understanding of the clarinet-player system. The current version is very primitive: it was put together in a hurry for the competition. But in the next year or so we shall use it to understand a range of questions:
* Why does a clarinet reed squeak? How can you stop it?
* What are the important parameters in a good sound?
* How important are tongue position, soft palate, glottis? What are the best combinations?
* How important is lip damping, and how does it depend on the reed?
* What are the important parameters in fine pitch control?
* What are the important parameters in expressive performance?
* What is necessary to convey warmth?
* What is necessary to follow a conductor?

To some of these, of course, we already have answers from our previous research. But we want to have more confidence in those answers.

So for the Music Acoustics Lab, this robot is a very useful tool. It was also a good project for two undergraduate students (Paul and Jean) in physics: a project that required a range of experimental and analytical techniques. The other groups in the robot team have different motivations.

For Mechanical Engineering, this robot was an interesting challenge. It was a good undergraduate student project for Kim: a range of questions to answer and difficulties to overcome. - It was also an interesting challenge for Mark, a Computer Engineering student Mark. In fact all of the students involved were highly motivated, worked well, learned a lot -- and had a good time. For university staff, this alone would justify the project.

For NICTA (a national research centre in ICT), the contest was a formal challenge. A good way of displaying expertise and applications in embedded systems, and a good way of inspiring students. (John Judge is from NICTA).

The team details and some more discussion is at Music Acoustics.

Most of the time, we study real musical instruments, real musicians, the voice and the ear. Some of this is sponsored by companies (instrument makers, a medical device company, a museum), but much of it is curiosity research.

For us, the robot project complements one of our areas in which we study real musicians and how they play. We want to know, in some detail, why a real musician plays better and makes a better sound than a beginner. (Curiosity research, but with an obvious application in music teaching and sometimes instrument design.)

The robot is a tool for testing our understanding of the clarinet-player system. The current version is very primitive: it was put together in a hurry for the competition. But in the next year or so we shall use it to understand a range of questions:
* Why does a clarinet reed squeak? How can you stop it?
* What are the important parameters in a good sound?
* How important are tongue position, soft palate, glottis? What are the best combinations?
* How important is lip damping, and how does it depend on the reed?
* What are the important parameters in fine pitch control?
* What are the important parameters in expressive performance?
* What is necessary to convey warmth?
* What is necessary to follow a conductor?

To some of these, of course, we already have answers from our previous research. But we want to have more confidence in those answers.

So for the Music Acoustics Lab, this robot is a very useful tool. It was also a good project for two undergraduate students (Paul and Jean) in physics: a project that required a range of experimental and analytical techniques. The other groups in the robot team have different motivations.

For Mechanical Engineering, this robot was an interesting challenge. It was a good undergraduate student project for Kim: a range of questions to answer and difficulties to overcome. - It was also an interesting challenge for Mark, a Computer Engineering student Mark. In fact all of the students involved were highly motivated, worked well, learned a lot -- and had a good time. For university staff, this alone would justify the project.

For NICTA (a national research centre in ICT), the contest was a formal challenge. A good way of displaying expertise and applications in embedded systems, and a good way of inspiring students. (John Judge is from NICTA).

The team details and some more discussion is at Music Acoustics.

A colleague told me of this discussion and suggested that I give a brief explanation of the motivation for this project. I'm from the Music Acoustics Group at UNSW. We maintain a large web site http://www.phys.unsw.edu.au/music/ for the benefit of musicians, students and interested others. It has more details on the robot. The introduction on our site is aimed at a good high school student, but if you go deep enough it leads to our technical research papers. - Most of the time, we study real musical instruments, real musicians, the voice and the ear. Some of this is sponsored by companies (instrument makers, a medical device company, a museum), but much of it is curiosity research. - For us, the robot project complements one of our areas in which we study real musicians and how they play. We want to know, in some detail, why a real musician plays better and makes a better sound than a beginner. (Curiosity research, but with an obvious application in music teaching and sometimes instrument design.) - The robot is a tool for testing our understanding of the clarinet-player system. The current version is very primitive: it was put together in a hurry for the competition. But in the next year or so we shall use it to understand a range of questions: * Why does a clarinet reed squeak? How can you stop it? * What are the important parameters in a good sound? * How important are tongue position, soft palate, glottis? What are the best combinations? * How important is lip damping, and how does it depend on the reed? * What are the important parameters in fine pitch control? * What are the important parameters in expressive performance? * What is necessary to convey warmth? * What is necessary to follow a conductor? - To some of these, of course, we already have answers from our previous research. But we want to have more confidence in those answers. - So for the Music Acoustics Lab, this robot is a very useful tool. It was also a good project for two undergraduate students (Paul and Jean) in physics: a project that required a range of experimental and analytical techniques. The other groups in the robot team have different motivations. - For Mechanical Engineering, this robot was an interesting challenge. It was a good undergraduate student project for Kim: a range of questions to answer and difficulties to overcome. - It was also an interesting challenge for Mark, a Computer Engineering student Mark. In fact all of the students involved were highly motivated, worked well, learned a lot -- and had a good time. For university staff, this alone would justify the project. - For NICTA (a national research centre in ICT), the contest was a formal challenge. A good way of displaying expertise and applications in embedded systems, and a good way of inspiring students. (John Judge is from NICTA). - The team details and some more discussion is at http://www.phys.unsw.edu.au/jw/clarinetrobot.html Music Acoustics.

A colleague told me of this discussion and suggested that I give a brief explanation of the motivation for this project. I'm from the Music Acoustics Group at UNSW. We maintain a large web site http://www.phys.unsw.edu.au/music/ for the benefit of musicians, students and interested others. It has more details on the robot. The introduction on our site is aimed at a good high school student, but if you go deep enough it leads to our technical research papers. - Most of the time, we study real musical instruments, real musicians, the voice and the ear. Some of this is sponsored by companies (instrument makers, a medical device company, a museum), but much of it is curiosity research. - For us, the robot project complements one of our areas in which we study real musicians and how they play. We want to know, in some detail, why a real musician plays better and makes a better sound than a beginner. (Curiosity research, but with an obvious application in music teaching and sometimes instrument design.) - The robot is a tool for testing our understanding of the clarinet-player system. The current version is very primitive: it was put together in a hurry for the competition. But in the next year or so we shall use it to understand a range of questions: * Why does a clarinet reed squeak? How can you stop it? * What are the important parameters in a good sound? * How important are tongue position, soft palate, glottis? What are the best combinations? * How important is lip damping, and how does it depend on the reed? * What are the important parameters in fine pitch control? * What are the important parameters in expressive performance? * What is necessary to convey warmth? * What is necessary to follow a conductor? - To some of these, of course, we already have answers from our previous research. But we want to have more confidence in those answers. - So for the Music Acoustics Lab, this robot is a very useful tool. It was also a good project for two undergraduate students (Paul and Jean) in physics: a project that required a range of experimental and analytical techniques. The other groups in the robot team have different motivations. - For Mechanical Engineering, this robot was an interesting challenge. It was a good undergraduate student project for Kim: a range of questions to answer and difficulties to overcome. - It was also an interesting challenge for Mark, a Computer Engineering student Mark. In fact all of the students involved were highly motivated, worked well, learned a lot -- and had a good time. For university staff, this alone would justify the project. - For NICTA (a national research centre in ICT), the contest was a formal challenge. A good way of displaying expertise and applications in embedded systems, and a good way of inspiring students. (John Judge is from NICTA). - The team details and some more discussion is at http://www.phys.unsw.edu.au/jw/clarinetrobot.html Music Acoustics.

Though coming from very different directions, both LQG pioneer Lee Smolin and Stephen Wolfram, who needs no introduction here, have opined that the best candidate as the fundamental level of a discrete physics (i.e. where the appearance of being continuous is emergent) is a graph theoretic network of nodes and links where it ceases to make sense to ask what they are made of. (This is also explored in Greg Egan's Schild's Ladder .) The basic idea is that there is some simple enough but cosmologically consistent transformation rule which produces the next local state of the graph from the current local state, supposedly at the Planck scale (of order 10^43 times per second).

A likely scenario is that "somewhere" long unreachable beyond our event horizons, there was a region of network sustaining chaotic inflationary expansion in which a bubble of more conservative physics emerged. Our conservative bubble only exhibits polynomial (near cubic) growth but that was enough to separate it from the exponentially growing seed graph.

My current betting is that Type 1a Supernovae, or at least some more precise analogue thereof in our parent cosmos, seed new outbreaks of chaotic inflation in which a new generation of more conservative bubble cosmoses arise, the whole process being susceptible to selection for fecundity and constrained only by the need for a viable history to some initial conditions simple enough to have just happened, presumably for no better reason than because nothing is unstable.

Haskell has parMap for that sort of situation. I've been using parMap to speed up a raytracer I'm writing. I'm getting less than linear speedups for some unknown reason, but it does help and it's easy to use. (I switched from ocaml to haskell partly because I wanted the parallelism, and partly because I wanted to learn haskell.)

They're about 20,000 km up, and orbit about twice per day, according to http://www.gmat.unsw.edu.au/snap/gps/gps_survey/chap2/222sats.htm

/frank

For your interest, here is some information on how PLATO got to Dome A.

The PLATO modules were built at the University of New South Wales in Sydney, Australia. Instruments were provided by our collaborators at a number of universities in China, the US, and the UK.

In late November 2007 PLATO was trucked 3912 km to Perth, where it joined a Chinese icebreaker for a two week trip to Zhongshan station on the edge of Antarctica. A helicopter then lifted the modules off the ship and about 100km inland where they joined a traverse for the ~1200 km journey to Dome A.

The traverse was an amazing feat. 17 people, 5 tractors. PLATO itself weighted about 10 tonnes. The traverse moves at speeds of 5-10 km per hour each day for 10 hours, and then rested for 14 hours. After three weeks of this, they arrive at Dome A. I am told that the undulating motion of the tractors over the ice can give you "sled sickness", an unpleasant variety of seasickness.

The team spent 10 days at Dome A, and did a fantastic job of installing the experiments and getting everything working. The temperatures were around -30C, which isn't much of an issue at low wind speeds. The altitude (4090m) is more of a problem, as it makes physical work exhausting, and there are difficulties with sleeping, mental acuity, etc.

Much more information, and a diary of the trip by the Chinese team members, is at http://mcba11.phys.unsw.edu.au/~mcba/plato.

As one of the University of New South Wales people involved, I thought slashdot might like some information on the computer systems that PLATO uses.

PLATO uses two redundant PC/104 form factor computers running Debian Etch. The computers boot from a 4GB flash disk (we tested 5 different models in the lab, and found one that worked reliably to -60C, despite only being spec'ed to -25C; all the other models worked to -40C, but had problems below that).

We use a readonly filesystem, with /home, /etc, and /var being created on boot in a ramdisk. This works really well, and it is nice to be able to turn off the power at any time without being concerned about filesystem corruption. Needless to say, with no possibility of any human being on-site for the rest of the year, we have thought very carefully about reliability.

Bulk data storage is provided by terabytes of conventional disks, with the most precious data being backed up on ~64GB of USB flash disks. Conventional disks don't handle the altitude very well, so we don't like to rely on them.

Communication is via two Iridium satellite modems, running at 2400 baud. We can push software updates by sending a set of "Short Burst Data" messages of up to 2000 bytes at a time. We can also login to PLATO using ssh, and I'm logged in as I'm typing this and running experiments.

There is a CAN (Controller Area Network) bus running throughout PLATO and linking the two modules: the Instrument Module, and the Engine Module, 45m apart. Each of 11 nodes on the bus has a small Atmel board that can turn power on/off to experiments, digital and analog I/O, etc.

More info, photos, and links to the health and status data are at http://mcba11.phys.unsw.edu.au/~mcba/plato

Einstein's theory of relativity features time dilation. Maybe that can help.