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Comment Re:Wrong figure of merit. (Score 1) 131

The important figure of merit here is price per kWh of storage.

I agree. I asked about density because I assume that, if the energy density is low, that it will be prohibitively expensive. If a battery that can provide power to a city needs a city-sized tank of liquid, that would be expensive (in real estate cost if nothing else). But you are right, I don't actually care about the density, I care about whether this "pencils out" economically.

As long as it can provide grid-level power at a reasonable cost, it's interesting.

Comment I recommend Sonicare (Score 1) 102

I use and recommend a Sonicare electric toothbrush.

They aren't paying me to shill so if you prefer a different brand, buy that. (The Sweethome recommends this Oral-B toothbrush.) But Sonicare is working for me.

My teeth tend to accumulate tartar buildup quickly. (I'm not complaining; better that issue than having acidic mouth chemistry that erodes teeth.) It used to take a long and unpleasant time for my teeth to be cleaned.

I got my first Sonicare and started using it, and as it happened I had a dentist appointment about a month later. The dental hygienist took one look at my teeth and said "I can already tell you are doing something different, and whatever it is, I like it." I was stunned... this was after just one month! How much better would it be after six months!

That was years ago. I have been using the Sonicare and my teeth cleanings go more quickly and are less unpleasant.

A few tips.

The main one: let the Sonicare do the brushing... don't apply a lot of force with your hand. I have sometimes been guilty of this and it can have a negative effect on the gums, making them "recede" which you don't want. Just use light pressure and let the moving bristles do their thing.

Also, make an effort to let the bristles brush the gum line (where the teeth meet the gums). I used to have an issue with deep "pockets" in my gums, and the Sonicare seems to have stimulated my gums to grow and fill in the pockets. After I used it for a while, I only had the deep pockets in the corners of my mouth; and then I made an effort to brush all my gums, including in the corners, and I don't have any of the deep pockets anymore.

Sonicare has a deluxe edition that includes a USB-powered travel charger. I lust after that USB travel charger, but I can't bring myself to spend that much money on a toothbrush. http://www.slashgear.com/philips-sonicare-diamondclean-review-09201165/

This is what I have. For half the price of the deluxe edition I got two Sonicares, a charger, and a travel charger. The charger has a UV feature to sterilize the brush heads; it makes an annoying high-pitched whine that I can hear, so I never use it. Instead I use the travel charger, which works fine.

http://www.costco.com/Philips-Sonicare-Flexcare-Rechargeable-Sonic-Toothbrush-Premium-Edition-2-pk.product.100071852.html

Also, floss your teeth every night, seriously. It make a big difference.

Comment What's the storage density? (Score 4, Interesting) 131

The summary implies that this technology could be used for large-scale power, but I wonder what the storage density is.

Specifically I wonder how this compares to liquid metal batteries. If everything Professor Sadoway says about the liquid metal batteries is true, those really will provide grid-level storage of power.

Comment Fictional treatment in _David's Sling_ (Score 2) 514

David's Sling, a novel by Marc Stiegler, is about the first "information age" weapons systems. These are autonomous robotic weapons that use algorithms to decide which targets to hit, and the algorithms are designed to take out enemy communications and decision-making. The weapons would try to identify important comm relays and take them out, and would analyze comm traffic to decide who is giving orders and take them out.

The book was written before the fall of the Soviet Union, and the big finale of the book involves a massive Soviet invasion of Europe and the automated weapons save the day.

Unlike some portrayals of technology, this book covers project planning, testing, and plausible software development. It contains tense scenes of QA testing, where the team makes sure their hardware designs are adequate and that their software mostly works. (They can remote-update the software but of course not the hardware.)

Mostly they left the weapons autonomous, but there was a memorable scene where a robot was having trouble whether to kill someone, and the humans overrode the robot and had it leave the guy alone. (The guy was injured, and lying there but moving a little bit, and the robot was not sure whether the guy was already killed or should be killed again. Hmm, now that I think about it, this seems rather implausible, but it was a nifty scene in the book.)

http://www.goodreads.com/book/show/3064877-david-s-sling

P.S. I bought the book when it first came out, and there was an ad for a forthcoming hypertext edition that never came out. I think it was never actually made, but I wish it had been.

Comment The experts have spoken (Score 3, Interesting) 264

In other news, experts pointed out that rubber sheets provide a two-dimensional surface, while the real spacetime continuum provides three spatial dimensions and one of time. Experts also pointed out that rubber sheets have nonzero friction with rolling marbles, while empty space has zero friction; and that the rubber sheets do not provide the time dilation effects that gravity provides.

Experts also pointed out that the whole rubber sheet thing is what is known as an "analogy" and pretty much by definition is inexact.

Personally, I found the article interesting, but the tongue-in-cheek "Shame!" of the summary a bit over the top.

P.S. From TFA:

But the truth is that this work cannot diminish the extraordinary utility of this analogy. And so the public love affair with general relativity is safe. Long may it continue!

Comment Re:classroom tools (Score 2) 210

The Marxist utopia never will arrive. Communism doesn't work.

But people do occasionally contribute their time to projects such as Firefox, Linux, or Wikipedia. (All it takes is for their satisfaction to be greater than the perceived costs to them.)

You don't have to tell me to pay for textbooks I want... I've been buying O'Reilly ebooks like a junkie lately. But there are a lot of kids who could use free textbooks if they were available, and mark my words, people will write those textbooks over time.

If even one free textbook of good quality was released per year, it wouldn't take many years before a basic education could be done with only free textbooks. And there are a lot of people in the world who aren't starving but are trapped in crushing poverty. Returning full circle to my original comment, I'd like to see OLPC focus on the education part and stop trying to make their own hardware. They can do more good by making educational software and writing textbooks, and trusting that mass-market mobile devices will be inexpensive enough and work well enough.

Comment Re:classroom tools (Score 4, Informative) 210

Yes, because of course people will do hundreds of hours of work for free.

It would be deliciously ironic if you used a free software web browser such as Firefox to type the above comment.

Graduate students and professors need to "publish or perish". I'm hoping that at least some of them will use at least some of their publishing time to write free textbooks.

And, anyway, people are already writing books and giving them away. Take a look at BookBoon:

http://bookboon.com/en/textbooks-ebooks

Comment Re:classroom tools (Score 5, Insightful) 210

I'm hoping to see a trend where professors or graduate students write new textbooks and just contribute them to the public domain. Inexpensive tablets plus free textbooks means inexpensive education.

http://slashdot.org/comments.pl?sid=4123035&cid=44658533

It's still early days with ebooks, really. The publishers want to keep the prices high, but the barriers to entry into the market are low. Free textbooks will disrupt the pricing model.

Comment Implications for OLPC (Score 1) 210

The One Laptop Per Child project should change its focus from hardware to software. Whether this tablet is suitable for kids, or some other tablet, they can count on inexpensive Android tablets being available.

Could kids use these things for reading textbooks? Yes. Could kids run educational software that drills them on math and other subjects? Yes. Could kids even watch movies, look things up on Wikipedia, learn to touch-type with a USB or Bluetooth keyboard? Yes, yes, yes. Tablets like these are adequate for learning.

Will OLPC ever achieve massive economy of scale by making its own branded devices? Signs point to "no". Wikipedia reports that OLPC has shipped over 2.4 million laptops in its first 6 years; in comparison, Wikipedia reports that the Google Nexus 7 tablet sold over 4.5 million units in its first year, and over 7 million to date (less than 2.5 years).

I understand that OLPC has several goals, and that one of the goals is that OLPC devices be repairable. But a school could literally buy three of these DataWind tablets for the cost of a single XO-4! Suppose someone made a bundle of a DataWind, a protective case and a keyboard; that should all come in for less than half the cost of an XO-4. Never mind repairs, just buy twice as many of the things.

OLPC should make Android software, and lesson plans for teachers, but shouldn't build their own hardware anymore.

Comment Re:4 years later (Score 1) 129

we're tired of the constant promotion of second-rate codecs that put ideology ahead of technical concerns.

You say "ideology" as if it were just a difference of opinion. Free, open-source software under a free license cannot use patent-encumbered technology. It doesn't matter how good the technology is if you can't use it.

it's not even clear (from a legal perspective) whether these codecs really are patent-free

Actually, you are mistaken on this point. MPEG-LA spent over a year trying to put together a patent pool with which to extract royalties on VP8, and didn't find anything. Then Google gave them some money to go away, and Google has a legal document saying that MPEG-LA will not sue over VP8.

Now, I'm not a lawyer and this isn't legal advice, but it sure looks clear to me: if MPEG-LA couldn't find anything in a year of looking, and signed a legal release on top of that, then there's no danger that VP8 infringes on an MPEG-LA patent. And even less danger that there is some third party out there with a mysterious unknown patent that could swoop in out of the blue to cause trouble (likely for both MPEG-LA and VP8 if it did happen).

At the same time the fact that these codecs are being pushed opposite the existing MPEG codecs only fractures the market and slows the adoption of new video technologies. We end up with Mozilla and Google flailing around with alternative codecs rather than buckling down and doing what's necessary to secure the rights to use the MPEG codecs in the first place, only finally doing the right thing after they've exhausted every other option. Web browsers should have fully supported H.264 years ago.

This is an interesting claim. As far as I can tell, H.264 has not had its adoption slowed even a little bit by VP8 or VP9... could you provide a reference, please?

Google owns and runs YouTube. Do you think Google should shackle themselves to a technology that they don't own, such that they would have no recourse if the licensing authority were to jack the rates up? I think that the business justification for Google spending $100 million to buy On2 and then just give away the technology was to give YouTube a way out if H.264 became rapaciously expensive.

Just as Vorbis never displaced MP3 or AAC, VP8/VP9 may never displace H.264, but if the threat they pose keeps the H.264 license fees from skyrocketing, then those projects were worth doing from Google's perspective.

And, while you may not care about the free software projects such as Debian, I personally think it's good if completely free projects have video formats they can use.

For that matter, I think it's good if completely commercial projects have free video formats they can use. Remember the brouhaha a few years ago where someone read the license for a new video camera, and it appeared that MPEG-LA was going to demand royalties on any video shot with that camera? MPEG-LA "clarified" its position and said that the legal language of the license doesn't mean what laymen think it means... but my understanding of patent law is that MPEG-LA could decide to impose any license they want on new cameras using H.264. I want a camera that uses nothing but free software internally so that I just don't need to worry that anyone has any sort of legal claim for royalties on video I shot with it.

Opus is a roaring success

And I'm hoping that Daala will be an equally roaring success.

Comment Re:MPEG LA patents running out (Score 4, Interesting) 129

Most of the remaining MPEG LA patents that matter run out in Q1 2014.

That sounds great, but could you please provide a reference or two to support it?

The sources I have seen suggest that it will be after 2020 before all the patents that affect even MPEG-2 will be gone. For example: this kuro5hin article lists 2023 as the year the last MPEG-2 patent runs out. And this page lists 2027 as the year the last H.264 patents run out.

If I'm understanding you correctly, you are saying that the most essential patents are running out, so it should be possible to make a patent-free coder and decoder that would cover a usable subset of the MPEG standards?

Do you predict that a patent-free MPEG-2 decoder capable of playing DVDs would be possible within a year?

Comment Re:Living on Debian Time (Score 1) 152

I could have been mistaken... maybe he was planning to use Nemo rather than Caja. That would make more sense; Nemo is a fork of the 3.x version of Nautilus and should fit better with a GNOME 3.x desktop.

Last time I tried Cinnamon the basics worked but the whole user experience was very rough. Like, I had to make a string of format codes to get the clock to display what I wanted, drag-and-drop didn't work to put launchers on a panel, that sort of basic thing.

Are you using Cinnamon? Have they improved the polish on the user experience yet?

I wish the Cinnamon guys well. For now, the easiest thing is just to run MATE, but in the long run my computers will probably all end up running Cinnamon.

Comment Re:Living on Debian Time (Score 1) 152

It's my understanding that a lot of stuff had to be sorted out to prevent clashes

I'd like a citation on that, please.

My understanding is that GNOME 2.x clashes with GNOME 3.x, so right at the beginning of the MATE project they worked very hard to rename everything. "libgnome" became "libmate" and so on, specifically so that MATE would not clash with GNOME 3.x. The MATE guys did all this work years ago, so clashing never was a problem for MATE and isn't now.

In further support of this idea, I will remind you that Ubuntu and Debian have had MATE packages available in alternate repositories for about as long as MATE has existed. I personally install MATE on every new Ubuntu system I install, and I never have seen any clashes.

As for "ensure that Debian doesn't end up with a bunch of garbage packages" I think you are getting closer. When MATE was first proposed for Debian, I believe the reaction was approximately "Debian already has GNOME and that is the standard. Go away." This confused me at the time, as Debian has literally tens of thousands of packages (including Xfce and other desktops that compete with GNOME), and I didn't see the harm in a handful of additional packages that filled a need that I personally cared very much about.

P.S. With the release of GNOME 3.0, a relative of mine embraced the GNOME Shell desktop and has been using it ever since. "Once you get used to it you can be pretty productive with it." He told me that he is rethinking that now, as the most recent changes from the GNOME guys rip out useful functionality from Nautilus. So he is either going to run GNOME Shell but install Caja (the MATE file manager), or just run MATE.

Comment Re:It tried to follow the plot (Score 4, Informative) 726

I agree with almost everything you wrote here. I'll just pick one nit.

He got in trouble for not taking his training seriously enough. The formal charges were "taking actions that could have resulted in death in real combat" but what he actually did was:

They were training in "simulated darkness" using infra-red "snooper scopes" which were a bit of a pain. He got frustrated and flipped the cope up and used unaided vision to check to see if anyone was in the area; because there was actually plenty of light he was able to see that it was safe. Indeed, he felt smug for being clever enough to do it that way... for avery brief time. However, the training suits had sensors that recorded the fact that he had flipped the scope up, and that is why he got in trouble.

Comment Not really fascist (Score 5, Interesting) 726

I must strongly disagree with the use of the word "fascist" with respect to the society portrayed in the novel Starship Troopers.

Let's look at how Wikipedia defines fascism:

One common definition of fascism focuses on three groups of ideas:

  • The Fascist Negations of anti-liberalism, anti-communism and anti-conservatism.
  • Nationalist, authoritarian goals for the creation of a regulated economic structure to transform social relations within a modern, self-determined culture.
  • A political aesthetic using romantic symbolism, mass mobilisation, a positive view of violence, promotion of masculinity and youth and charismatic leadership.

http://en.wikipedia.org/wiki/Fascism

None of these apply to the society portrayed in the book.

The first item: the sole means by which the government attempted to impart any point of view on the citizens was a high-school class called "History and Moral Philosophy" that was always taught by a full citizen, but which the student was not required to pass. The examples from when the protagonist took the class did debunk some of the tenets of communism, though. (Labor does not always add value. An unskilled cook can take pie dough and apples and produce a burned mess, where a skilled cook can produce a delicious dessert, so the "labor theory of value" in its simplest form is disproven by example.)

The second item: the government did not run businesses. The society operated in a free market. The amount of regulations imposed by the government was never explicitly spelled out, but my impression is that the amount of regulation was low, as discussions of business did not tend to rants about permits or bureaucratic interference.

The third one at first seems plausible, as the book is (in Heinlein's own words) intended to present lowly soldiers in a good light (as opposed to senior generals, Presidents, etc.). However, the government in the book did not promote such ideas. Instead, the government took steps to scare people off from becoming soldiers. For example, having a maimed military veteran sit outside the recruiting station and warn young people that they could get maimed like he had been. (Later, the protagonist meets this veteran again, and he is off-duty and wearing artificial limbs that look real and work about like the real thing, and the veteran's manner is completely changed; he congratulates the protagonist for choosing to serve in the infantry.)

My opinion could be slanted, as I am politically a minarchist libertarian, but the society in Starship Troopers appears to be a minarchist libertarian government. The government is relatively small and does relatively little, and what it does do seems to be mostly confined to defense and police. The common attitude among most of the population is that they want nothing to do with government, which seems unlikely if government was a major force in peoples' lives. (The protagonist's father has not earned the right to vote, and proudly tells the protagonist at one point that he is a third generation non-voter; why would he want to earn a vote? No profit in that, the time is better spent building the business.)

The described history in Starship Troopers went like this: During a time of wide-spread social upheaval, the old governments disintegrated and new ones formed. One of the new governments, mentioned as an example, used "scientific" techniques to pick who would be in charge; it failed. Eventually a bunch of military veterans banded together and began keeping some sort of peace within the area they were able to patrol, and this expanded to become a new system of government. Voting was limited to people who had served at least one term of service in the government. Service could be military but could also be anything else the government needed to have done, such as scientific research. Also, according to their laws, the government had to accept any volunteer and find some work for them to do. (Someone asked what would happen if a blind and deaf person applied for service; the answer was that even if the job was something silly like counting the fuzz on a caterpillar by touch, some work would be found.) The protagonist only wanted military service and did not apply for non-military service, but the option for non-military service was open to him. Finally, the vote was limited to people who had completed their government service but were no longer employed by the government; this wasn't discussed much, but the brief discussion was approximately that the society wanted to avoid the moral hazard of people using the political process to increase their own salary and/or benefits.

I'm afraid I must disagree with you that Heinlein always pursued the ideas of where a society breaks down. Starship Troopers shows a society not breaking down, but gearing up to fight against the threat of "the Bugs". In real life Heinlein was pro-freedom and anti-communist, and some people opine that the Bugs were intended as an allegory for communists. That's plausible. On the other hand, the book is not an exploration of the morality of war; the Bug War was presented as a simple moral situation, that the Bugs started attacking human colonies because Bugs like the same sort of planets humans like. Heinlein had no doubts as to whether World War II was a "just war" and his fictional Bug War was clearly described as a "just war". Humanity needed to defend itself, and was doing so. Anyway, the Bugs were an implacable enemy who started the war and couldn't be bargained with or reasoned with, making a very simple moral situation.

For a better example of showing the bad points of a society, read Starman Jones. In that novel, a system of guilds divides up the available jobs and jealously guards their own part of the job market; you cannot get a job as an astrogator without joining the Astrogator's Guild, and that guild was unlikely to let you join. (You needed to be invited in by a relative or close friend.) Or, for an even more nuanced look at a society, read Citizen of the Galaxy and see how the Free Traders are simultaneously the most free people in the galaxy, and yet their society chains them into rigid social structures.

In both books our heroes defeat the major dramatic conflict, but also find that society did not become utopia as a result.

On this point I agree with you completely. Heinlein wasn't too much for utopias. At the end of his career he wrote some weaker novels where the main characters lived in a highly advanced society of abundance, with disease and aging pretty much solved problems, but even those characters wound up having problems they needed to solve.

The movie was a shallow satire. The book was a thoughtful morality play.

I agree with these points. The satire in Robocop went over well, and I felt that the satire in the Starship Troopers movie was an attempt to go back to that same well; it fell flat for me. The book had a simple moral: the height of morality is to put yourself at risk to defend others from harm.

I still like the movie though, as was far more annoyed by the lack of jumpsuits than the political fun.

The lack of powered armor really bothered me. In the movie they used something very like an M-16 despite the fact that they were fighting giant bugs with nontrivial amounts of armor; they had hopelessly inadequate equipment and got slaughtered a lot. In the book the soldiers were highly mobile, heavily armed, and well-trained in the use of their weapons, and led by well-trained officers who used effective tactics. (The leaders were not portrayed as flawless, though; the first attack on the Bugs' homeworld, Operation Bughouse, was a horrible bloody disaster that devastated the military forces.)

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