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Comment Re:Probably 15.0 kW, not 150 (Score 1) 106

No. Typical usage in Europe is MAYBE 4kWh/year. Notice the difference between kW and kWh, please. They are very different - kW is power, kWh is energy. See: http://www.energylens.com/arti... for an explanation. You can find energy use for several countries at http://shrinkthatfootprint.com... Having said that, there is no way that 150kW powers only 10 houses. Louisiana uses more energy per household than any other state in the US (probably due to air conditioning): 15270 kWh per year (the average in the US is 10908 kWh). So, in Louisiana, a home is using (15270kWh/year)/(8765.81 hours/year) = 1.74 kW of power at any given time, on average. That means that a 150kW heliostat should power about 86 homes in Louisiana - during the time when the array is functioning (daytime, with some lag for heating up and cooling off). So, the article is not very useful, because it's not telling us how many kWh/day this heliostat produces. My guess is that they either got a decimal point wrong, or that 150kW measures the amount of solar power being CAPTURED, not the amount of power being GENERATED as electricity.

Comment Article is very poorly written (Score 1) 204

Let me dust of the old astronomy degree here...

Major problems:

  • White dwarf matter is nothing like normal matter. It is electron degenerate matter. The atomic number of the original atoms no longer mean much, if anything, so calling this a "diamond" is as far beyond stupid as degenerate matter is beyond the densities that you and I are familiar with in every day life. The core of a white dwarf is compressed so far, that the electrons and nuclei are crammed together much closer than their charges would like them to be. But, gravity has won this contest and pushed the electrons and nuclei VERY close together. There are no more "atoms" in a white dwarf, so calling it "carbon" is a stretch. This stuff would make a block of pure uranium look less substantial than a wispy puff of hydrogen. Normal rules for chemistry no longer apply.
  • A white dwarf would typically have about the mass of our sun, with the approximate volume of earth. There is no way that there is a white dwarf the "size of Jupiter" anywhere. Anything that large made of white dwarf matter would collapse into a black hole. So, it might be the "mass of Jupiter". But, that means it must have started out much more massive, and been whittled down by some process. I'm not certain that close proximity to a pulsar could do that. This stuff is held together VERY strongly by gravity. Pulling it apart might be possible, but... given the lousy writing in the rest of the article, I'm not convinced that they got this part correct, either.
  • This stuff is not any kind of "crystal". A crystal has to be a regular lattice of some sort. Electron degenerate matter doesn't do lattices. I suppose if it were cooled enough, it might settle down into something vaguely like a crystal. But the universe isn't old enough (by MANY orders of magnitude) for a white dwarf to have cooled off enough to be anything but a horrifyingly dense seething mass of gooey hellfire. Even when it does cool off, calling it a "crystal" would be like saying I'm hot like Natalie Portman, because we both have nice eyes - there's more bullshit than truth in that statement.
  • The science that "inspired" this article is probably fine. But, the article is crap.

Comment Re:We always knew that ipv6 adoption would be mess (Score 1) 376

Well, if it's going to cost your organization a lot to move to IP6, then I guess it sucks to be you. Anyone even remotely involved in IT has known, for a decade or so, that this was coming sooner or later, and if you're so far behind that it's going to cost you a ton of money to make the switch, then CLEARLY, your organization has had it's head in the sand, and has been willfully ignoring what everyone else knew was coming. If the expense of switching is going to ruin your business, then good riddance, I say. That's not "survival of the fittest", it's just "survival of the not completely brain dead".

In addition, your figure of trillions is ridiculous. You're off by many orders of magnitude. There is absolutely no way in hell it's going to cost everyone on the planet $1000 or more to switch to IP6. I don't know where you're getting that figure, but please put it back wherever it came from.

Everyone needs to decide on an IP6 go live date, and an IP4 shutoff date, that's VERY soon afterward. If we let people get by with IP4 for too long, they'll just bitch and whine, and insist there's no money to make the switch, etc., and drag their feet, and complain about not being able to get to IP6 only addresses. Bite the bullet and switchover, please. Let's get this done and get back to work.

Comment Re:DP, Algorithms, OOP A&D, Threading, etc (Score 1) 396

Sorry. I have to disagree with you completely. No user defined libraries... only rudimentary argument passing between scripts, needing to use the API to access list elements, no arrays. Come on! It's a horribly-designed language, even for animating link sets. You can't even smootly animate prims with it, without making them physical. And the main problem is, that there's nothing else you can use to automate anything in SL EXCEPT for LSL. Yes, people try to write complex things that LSL wasn't designed for, but it's not because they don't understand it's limitations, it's because it's the only option. So, if anything, you've just proven my point. They developed an in-house language, and it miserably failed to meet the needs of it's users. How is that a well-designed language, exactly?

The issue is, that the problem domain was NOT well-understood by the designers. They thought they understood what people would need to automate in SL, and they were VERY wrong. Had they used lua, python, perl, scheme.. hell, ANYTHING else, they'd have done a better job. This is a case where the designers thought they could write a language from scratch, and they failed miserably. Anyone who's designed a DSL from scratch knows that people will push the boundary of the original intention. It's the designer's job to anticipate what the users want and need. I still call this an epic fail at Linden Labs.

And, yeah, I've done a lot work with microcontrollers, and cut my programming baby teeth on 6502 assembly. I know about "programming in the small".

Comment Re:DP, Algorithms, OOP A&D, Threading, etc (Score 2, Interesting) 396

This is an excellent list. I was self-taught from the age of about 12, and thought I was an excellent programmer until I was about 25. Having earned BS and MS degrees in Astronomy and Mathematics, I'd written a fair number of programs, and had a decent command of about 7 languages. Then I went to graduate school for Computer Science. And I found out that my knowledge was SEVERELY lacking, both in breadth and in depth. How much of my missing knowledge was relevant to day-to-day programming tasks? Well, perhaps not surprisingly, not much. However, when I come across some issue where my CS education is useful, it's HUGELY useful, and enables me to tackle a problem in far less time, and most importantly, implement a correct solution. It also lets me know when I need to turn over a portion of a project to a specialist. In other words, I'm now more aware of the things that will become a time sink, and increase uncertainty if I attempt them. This ability to do "project triage" is one of the benefits of a well-rounded CS education.

I think that this is the main reason that you'll hear a lot of people say that a university CS education isn't very useful. For about 98% of the things you work on, it really doesn't make you any better than someone who's self-taught. But that remaining 2%... it can mean the difference between blowing months of time on a crappy solution to a problem, or knowing how to put a good one together in a few days time. So, on the whole, a Uni education can make you a far better programmer, even though you won't necessarily find yourself pulling tricks out of your Uni bag every day.

As an example I'll add my 2 cents about only one of the topics mentioned above: Programming Languages. There are many cases where programmers try to develop a "simple" scripting language for embedding in an application. This is one thing that very few people (even uni-educated) should attempt. Proper language design and parsing is VERY difficult, and there are at least a half-dozen well-designed scripting languages that can be literally dropped in to an application with almost no effort when compared to the complexity of rolling your own. And yet, we see time and time again, people attempting to write one from scratch. One of the worst examples I can think of off the top of my head is LSL (Linden Scripting Language), used in Second Life. It's an absolute nightmare of a language. And yet, it made it into a large-scale product like Second Life.

There ARE many cases where a domain-specific language (DSL) can be incredibly useful, especially when the language does not need to be a general-purpose one. In my experience, it's rare for a programmer (no matter how their skills were gained), to create a good DSL without a strong grasp of at least a dozen programming languages or so. University-educated programmers tend to be a better judge of whether they are up to the task of designing and/or implementing a language(at least, after they've tried their hand at it once or twice).

Comment OUCH! (Score 1) 293

If a sheet of glass 15 to 30 atoms thick breaks, I'd expect it to be extremely hazardous to clean up. The pieces would be incredibly sharp.


Music By Natural Selection 164

maccallr writes "The DarwinTunes experiment needs you! Using an evolutionary algorithm and the ears of you the general public, we've been evolving a four bar loop that started out as pretty dismal primordial auditory soup and now after >27k ratings and 200 generations is sounding pretty good. Given that the only ingredients are sine waves, we're impressed. We got some coverage in the New Scientist CultureLab blog but now things have gone quiet and we'd really appreciate some Slashdotter idle time. We recently upped the maximum 'genome size' and we think that the music is already benefiting from the change."

ASCAP Seeks Licensing Fees For Guitar Hero Arcade 146

Self Bias Resistor writes "According to a post on the Arcade-Museum forums, ASCAP is demanding an annual $800 licensing fee from at least one operator of a Guitar Hero Arcade machine, citing ASCAP licensing regulations regarding jukeboxes. An ASCAP representative allegedly told the operator that she viewed the Guitar Hero machine as a jukebox of sorts. The operator told ASCAP to contact Raw Thrills, the company that sells the arcade units. The case is ongoing and GamePolitics is currently seeking clarification of the story from ASCAP."

Hand Written Clock 86

a3buster writes "This clock does not actually have a man inside, but a flatscreen that plays a 24-hour loop of this video by the artist watching his own clock somewhere and painstakingly erasing and re-writing each minute. This video was taken at Design Miami during Art Basel Miami Beach 2009."

The Struggle For Private Game Servers 125

A story at the BBC takes a look at the use of private game servers for games that tend not to allow them. While most gamers are happy to let companies like Blizzard and NCSoft administer the servers that host their MMORPGs, others want different rules, a cheaper way to play, or the technical challenge of setting up their own. A South African player called Hendrick put up his own WoW server because the game "wasn't available in the country at the time." A 21-year-old Swede created a server called Epilogue, which "had strict codes of conduct and rules, as well as a high degree of customized content (such as new currency, methods of earning experience, the ability to construct buildings and hire non-player characters, plus 'permanent' player death) unavailable in the retail version of the game." The game companies make an effort to quash these servers when they can, though it's frequently more trouble that it's worth. An NCSoft representative referenced the "growing menace" of IP theft, and a Blizzard spokesperson said,"We also have a responsibility to our players to ensure the integrity and reliability of their World of Warcraft gaming experience and that responsibility compels us to protect our rights."

Black Screen of Death Not Microsoft's Fault 583

Barence follows up to the ongoing Black Screen of Death Saga by saying "Microsoft says reports of 'Black Screen of Death' errors aren't caused by Windows Updates, as claimed by a British security firm. The software giant claims November's Windows Updates didn't alter registry keys in the way described by Prevx, which said that the Microsoft Patches caused PCs to boot with just a black screen and a Windows Explorer window. Microsoft is now blaming the problem on malware. Prevx has issued a grovelling apology on its own blog."

Comment Flatland "sequel" (sort of) (Score 1) 630

Others have mentioned "Flatland" by Edwin Abbott, which I also strongly recommend.

"Geometry, Relativity, and the Fourth Dimension" by Rudolf Rucker should be accessible to a high school student. It revisits Flatland, so that's probably a good book to read first.

"The Drunkard's Walk: How Randomness Rules Our Lives" by Leonard Mlodinow is an easy and entertaining read, and talks about how human intuition is often wrong when making probability estimates.

"Knotted Doughnuts" by Martin Gardner is a compilation of brain-teasers from Scientific American. Gardner has published several of these collections, but this is my favorite.

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