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Comment Erm... (Score 3, Insightful) 102

The 130-page report (PDF) shows that Li-on batteries will drop from $550 per kilowatt hour (kWh) in 2014 to $200 per kWh by 2020

The going rate for residential electricity in the U.S. is about $0.11/kWh. So basically if these batteries charge/discharge once per day (as the case would be for solar), and you want the batteries to only add (say) 20% to the price of the generated electricity in order for it to remain cost-competitive (note: wind is nearly cost-competitive, solar is still about 2x-3x more expensive), then it currently takes $550 per kWh / ($0.11 per kWh * 20% * 365 cycles/yr) = 68.5 years for these batteries to pay for themselves, but by 2020 it will take 27.4 years. Yay progress?

Unless the levelized price for renewable generation drops substantially below that of coal, I don't see how this will "spur renewable energy adoption" except for regions where electricity prices are substantially higher (e.g. Hawaii, $0.30/kWh)

Comment Re:So much for net neutrality (Score 1) 250

1. a data cap that from an "unlimited" that is not unlimited, since the user signed a contract that had some sort of fair use policy allowing redefinition of the word "unlimited" by the ISP,for marketing purposes;

I think most (all?) carriers have dropped unlimited data plans. Sprint is the only one I'm not sure about.

The remaining people with unlimited plans are grandfathered in (I'm one). Legally, the carrier is not required to continue to keep these people on those grandfathered unlimited plans. Once your multi-year contract is up, your service is month to month. You are free to cancel it at any time, but the carrier is also free to cancel it at any time. The carriers have, as a courtesy, just been allowing customers on the old plans to continue month-to-month under the terms of the old plan. There is no legal requirement for them to do so, and they could in theory just force you into a current data capped plan if they wanted.

I agree marketing data plans as "unlimited" in the first place was stupid. But it happened, and it's in the past. Carriers are now doing the right thing by specifying what your bandwidth limit is. The "my contract says unlimited" argument really carries little legal weight (unless a carrier still offers an unlimited data plan).

2. Did I read that right about them targeting torrent and p2p users first? Didn't the US just pass a net neutrality law? Isn't protocol-specific "accusing" a type of discrimination punished by law when it concerns American citizens, because it would automatically assume the content these users were trading was illegal without a serious base for such accusation? I mean, seriously. Who gave these corporate douches the power to decide how their service is to be used. It's about time all service providers understand that a user has a right to privacy that goes well beyond his right to sniff on the user's content.

Understand that the typical Internet service you pay $50/mo for is actually a shared service. If you to try to buy (say) 20 Mbps for your sole, exclusive use, it would cost you around $2000-$5000/mo. The only way the ISP can offer it to you for $50/mo is by having you share it with about 100 other people. And the only way sharing it with about 100 other people works is if on average each of them uses about 65 GB/month.

The easy way is to set a bandwidth limit of about 100 GB/mo (most customers won't come anywhere near 65 GB/mo so you have some extra headroom). But you can't do that with unlimited plans. So you can either let the service go to hell with transmission rates slowing to a crawl due to everyone torrenting and P2Ping 24/7. Or you can selectively slow down services which most people don't care about in order to maintain speed in the services most people do care about (web browsing). If you're going to say they're not allowed to do that because of net neutrality, then that is equivalent to choosing the "go to hell" option.

There's no free lunch here. You can pay for a dedicated line and have no usage restrictions, or you can pay the shared rate and accept some usage restrictions and bandwidth limitations. The idea that you can pay the shared rate but use it as if were a dedicated line is a fantasy sold to you by unscrupulous marketers.

Comment Re:You keep using that word. I don't think it mean (Score 2) 250

I agree - especially if tethering is not allowed.

Tethering and unlimited data are an either/or. Either you can have unlimited data but no tethering, or you can have tethering but with data caps.

Frankly, I think the latter makes a lot more sense. Tethering is a very useful tool built into every wifi-capable Android phone by default (the carriers disable it). If you have it, it eliminates the need to get a separate cellular data plan for your laptop, tablet, etc, and you're no longer limited to using those devices only within earshot of a wifi hotspot. I show people how to tether with their phones, and they're flabbergasted when they realize the possibilities it opens up. e.g. Kids can watch a streamed movie on their tablet during a long road trip. You can navigate using a bigger tablet as your map, instead of the tiny screen on your phone).

Logically, it makes no sense to discriminate based on where the data will end up - your phone or your tablet/computer. That's like a restaurant saying you aren't allowed to share the food you buy with someone else - only you are allowed to eat it. You've paid for the food/data, why should they have any say over what you do with it? On unlimited plans, disallowing tethering is really just a roundabout way to limit bandwidth (like buffet restaurants don't allow you to share food with someone not buying the buffet). Why do that and suffer the collateral damage it causes, when you can just limit bandwidth directly with a cap?

Comment Re:No Teaching Experience? (Score 1) 58

Some people are great at teaching, others are not.

I believe this is a self-perpetuating myth. What the data shows is that new teachers in America improve rapidly over the course of about three years, after which they are about as good as they'll ever be. So it's certainly not the case that some people are just naturally teachers; great teachers have to learn the craft through practice, and that learning comes after they finish their official training.

But maybe what we're seeing is that it takes teachers three years to reach their inborn teaching potential, after which they no longer are able to learn anything more that might help them. My question is, how do we know that? How do we know that American teachers are actually completely incapable of becoming better teachers after three years of in-classroom experience?

We don't know. The remarkable thing is that until very, very recently, very few American school systems have actually attempted to systematically improve the performance of their teachers through observation of what they're doing in the classroom. They may have "professional development" where they get more of the same kind of theoretical training they got in education school, but they usually don't follow up to see how the teacher actually puts that to use, or even to identify bad habits the teacher may have developed over the years, or good habits he hasn't. In my kids' school system kids are sent home early on "professional development days" so that working with actual students won't get in the way of a teacher's skill development. It's like trying to make someone a better baseball hitter by banning bats and balls from training and simply talking to players about the theory of biomechanics.

Imagine you own a factory and your assembly line is turning out too many defective widgets. How would you address that problem? Would you send your engineers to a seminar every year on manufacturing theory and ask them to make design changes when they came back from that seminar? Or would you go over the assembly line with a fine tooth comb? While the seminar idea has it's merits, it's too slow and it'd take sheer luck for the seminar to hit on the particular problem that's affecting the line.

In America we have a simple model for improving the teaching at a bad school: fire the bad teachers and hire better ones. But imagine, just for a moment, it is possible to use empirical methodologies to improve the performance of any teacher. Imagine for a moment some bad teachers could be transformed into mediocre ones; some mediocre teachers into good ones; and some good teachers into great ones. In a world where that was possible there'd still be a place for the hire and fire strategy, but relying on that strategy exclusively leads to two unfortunate and unnecessary results: (1) Poor districts have to make do mostly with inadequate teaching and (2) teaching in rich districts tends to be adequate, but great teaching remains uncommon.

Sound familiar?

Comment Re:Because this will be unlike Biosphere 2 how? (Score 5, Informative) 73

To answer your question, smaller habitat, no experiment at maintaining atmospheric composition, outside excursions in "space suits" etc. Its not very much like Biosphere II.

As for why not under the sea or Antarctica I can give at least three reasons. (1) cost of building, transporting and maintaining the habitat; (2) all the support and research personnel live in Hawaii, above water; (3) the research objectives don't require putting the experiment in a dangerous or inaccessible place.

Now someday when we have an actual habitat design along with all the actual support systems we plan to send to Mars, a trial on top of a super high mountain would make sense as a kind of Mars analog. But we don't have such stuff to test so we don't need the Mars analog with all the expense and complication.

Comment Re:Furthermore, Saudi Arabia must be destroyed (Score 4, Insightful) 380

Not everyone in Saudi Arabia are bedouin; in particular the ruling House of Saud is descended from town dwelling Arabs.

I'll go out on a limb and guess that not everyone in Saudi Arabia is worthless. Even people involved in managing their oil. And as for the elite they don't seem to be worse than anyone else who's inherited oil-based wealth; they've managed that for the long term benefit of themselves and their families. If they're ostentatious with their wealth, well they have a lot of it and it hasn't bankrupted them yet.

So there's no rational reason to want to destroy Saudi Arabia. But there's every reason not to want to be so dependent upon them.

Comment Re:From TFA: bit-exact or not? (Score 1) 172

Given that CPU and memory get less expensive over time, it is no surprise that algorithms work practically today that would not have when various standards groups started meeting.

I remember when the preliminary JPEG standard first showed up in the early 1990s, a 640x480 8-bit GIF would decode and display in about a second on my PC. A 640x480 24-bit JPEG took about 30 seconds. JPEG's strength back then was its much smaller file size. Aforementioned GIF was about 200 kB, while the JPEG was about 35 kB with better colors (if your video card could do 24-bit color). That was a huge deal when most of us were still using 14.4 kbps modems and hard drives were around 500MB - 2GB.

Comment Re:No, obviously (Score 1) 258

unless of course you're terrified of computers and networks, view them as tantamount to witchcraft, don't understand them, and hate and fear anyone who does.

This is the way the world works. The 50+ generation grew up in a world without computers. The 30+ generation grew up during the transition to widespread computer use. And anyone younger grew up when computers were ubiquitous.

As long as those (currently) 50+ people are alive, these laws will probably stay in the books for the reasons you cite. As they grow old and die, people will start talking about getting rid of the "silly" distinction of crimes using a computer. And when only those currently under 30 are alive, they'll see no point to these computer-specific laws and will repeal all of them.

In other words, people's opinions don't really change. They just grow old and die, causing a shift in the prevalent opinion of the electorate.

Comment Re:A simple test is in order (Score 1) 444

Well, this is a bit like parents who take their kids to get vaccinated and a few hours later that kid exhibits the first signs of autism. It's an immensely compelling coincidence. You'd have to (a) know that autism symptoms often have a rapid onset and (b) realize that when they do they can follow any commonplace childhood event. Even if you did it'd still be hard to shake the suspicion if it happened to your kid.

Somebody points a IR remote at your friend; he gets up and has a brief moment of orthostatic hypotension -- also known as a "dizzy spell" brought on by a sudden drop in blood pressure -- just at the moment the guy pushes the button. Orthostatic hypotension can happen to anyone, but if your friend isn't otherwise prone to it that can be a very compelling coincidence; and many of the symptoms of hypotension can be reproduced by psychological stress.

If something like that happens to you people will say, "oh, it's all in your head," but the thing is that all suffering is inside peoples' heads. One of the worst kinds of pain you can have is passing a kidney stone, but if you happen to be in a coma at the time you won't feel a thing. Distress produced within the brain is indistinguishable to the subject from distress produced outside the brain. Having an external explanation for that distress can make someone feel like they have some control over what is a disturbing experience, and shooting holes in that explanation isn't going to help unless you can offer them a better handle on it.

Sometimes I think we'd be better off if we just brought back shamans and witch doctors.

Comment Re:39% without secondary false-positives. (Score 1) 252

Part of the problem is one of incentives: the incentives to do a study which simply replicates a pre-existing study is low, and many journals won't even publish them.

Yeah that's what I noticed too (my minor was in cognitive psychology - like trying to figure out AI from the opposite direction). When Fleischmann and Pons posted their cold fusion paper, every physics lab in every school grabbed it and tried to replicate it, just because of how cool it would be if it actually worked. I never saw the same zeal to replicate interesting results in psychology. In fact you are banned from trying to replicate some of the most notable experiments because of ethical issues. It always felt to me like "this other guy tried it and this is what happened, so it must be true."

Comment Re:Counter measures (Score 1) 123

Chrome plating is only about 70% reflective. A bathroom-variety mirror is only about 75% reflective. The remaining 25%-30% of energy from the laser would be absorbed by the drone as heat. Aluminum coatings used on telescope mirrors can get to about 90% reflectivity, about 98% with good coatings. But that's at a specific wavelength (visual spectrum), and they're very delicate (only about 100 nm thick) and degrade as cruft settles on them. That's why electroplated chrome is more popular for decorative reflectivity - it's much more durable. (Silver actually has better reflectivty, but it quickly tarnishes upon contact with the air. Aluminum does too, but the resulting aluminum oxide is transparent in the visible spectrum and forms an airtight barrier protecting the remaining aluminum.)

So all a mirrored drone would do is increase the amount of time it takes for a laser to shoot it down. If drones did start to go that route, the obvious countermeasure would be to make the laser more powerful. It's a lot easier to make the laser bigger than it is to keep the mirrored surface of a drone pristine.

Unrelated trivia: The best reflective surface is actually a prism, which relies on a phenomenon called total internal reflection - the same property which makes optical fibers work. Their biggest losses are actually at the air-prism interface where the light enters and exits the prism - typically 99.7%-99.8% transmission. They're highly directional though, so (unless someone can come up with an extremely clever design) wouldn't work omnidirectionally.

"We learn from history that we learn nothing from history." -- George Bernard Shaw