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Comment the US. (Score 1) 154

Then how is it that the top-left corner of my iPhone 4s says, “T-Mobile”?

I've had it for over a year. Bought an unlocked phone at an Apple store, stopped at the local T-Mobile store on my way home, oohed and aahed about it with the cute girl while she rummaged in the drawer for a micro-SIM, and made my first call on it in the parking lot before finishing the drive home.

It's with a fantastic pre-paid plan, too. I pay $2 / day on any day that I make even one phone call or transmit even one byte of network data, but everything is completely unlimited for the rest of that day. I telecommute, so I rarely use it for calls and even more rarely for data (thank to ubiquitous WiFi), which means I'm spending about as much over the course of a year as most people do in a single month. And I own the phone outright, with no lease or contract or any other restriction.

All on T-Mobile.



Comment If you think renewables are expensive... (Score 4, Insightful) 473

...just wait until you see how much those non-renewable alternatives like tar sands and coal-to-gas will cost you. And that's before you figure in the cost to clean up the mess they make.

Remember: deepwater horizon had a wellhead as far beneath the waves as Denver is above them, and the oil itself was farther below the seafloor than the peak of Everest is above sea level. Loooooooong gone are the days when you had to be careful with a pickaxe in Texas lest you set off a gusher.

Oh -- and it's petroleum that fertilizes our crops and powers our transportation infrastructure, and we've already burned up half of the planet's total reserves. The easy-to-get-to and high-quality half, of course.

Like it or not, the days of cheap energy are done and gone with. If we're smart, we'll bootstrap ourselves to a solar-based energy system, which won't be cheap, but it will give us more power than any of us can imagine. There's enough insolation just on America's residential rooftops to power the entire planet, for example. If we invest wisely, as Germany is doing, we'll sacrifice a little bit of short-term comfort for a lifetime of luxury. If we invest poorly, as Obama will have us do with his "Drill, baby! Drill!" energy plan... ...well, if we actually follow through with that, we're well and truly fucked.



Comment Re:What type of programmer? (Score 1) 767

As with any other field, there are good SQL programmers and bad ones.

A good SQL programmer would ever even think to mix data types in an output column (does your SQL implementation even allow that?), and well-written SQL runs orders of magnitude faster than anything you can do in an imperative language -- but only for those problems that can be solved with set theory. And a good SQL programmer knows what the limits of set theory are...and knows that you're almost always better off moving to a traditional language when you meet those limits rather than use the procedural kludges built into most SQL implementations. But, again, a good SQL programmer will be able to understand the set theory inherent in the original problem and isn't even going to think of reaching for the procedural kludges -- instead, a simple matter of turning something upside-down or moving it into a sub-select or the like will generally do the trick, and do so very quickly and very clearly.

I can't imagine a stored procedure with 7000 lines of code. Chances are excellent that either those 7000 lines need to be re-written to use set theory in a tenth as many lines that'll run a thousand (no exaggeration) times faster, or that it should have been written in COBOL instead.



Comment What type of programmer? (Score 4, Interesting) 767

I like to think I'm a more-than-competent SQL programmer, and I don't hurt myself too badly at Web and Windows Forms programming.

I work with somebody who does some great stuff in C# who can't warp his head 'round set theory and therefore has real problems with SQL.

I know somebody else who's a real monster with Cisco stuff (a Cisco employee with certifications coming out his ears), and I'd argue that creating networking and firewall rulesets is every bit a form of programming as anything I do...but he'd need some serious handholding just to do a "Hello World" program in Visual Studio.

I know another guy who can make COBOL sing and is not bad at SQL (though he prefers to write his SQL with more procedural code and less set theory than is good), but he wouldn't have much luck doing more than tweaking a Web form.

We're all programmers, all of us good at what we do, some of us great at what we do...and, yet, making any one of us look like rank amateurs at huge swaths of basic programming tasks wouldn't be hard at all.

Could we become good programmers outside our areas of expertise? Probably. But it took me quite a while to figure out how to truly think in set theory, and I'm not sure I'm capable of more than a handful such masteries in any given field in my lifetime.



Comment Re:Don't be a PV efficiency snob (Score 1, Interesting) 129

Don't be a price snob, either.

If we wanted to go 100% solar for electricity generation over the next 50 years, it'd only take about as much as we're currently spending on federal government pensions. No small chunk of change, to be sure, but peanuts compared to the other big projects our society doesn't even bat an eye on.

(Assume $2 / watt installed, not much below the current bottom end but well above what such huge economies of scale would push it to. Assume 1 MWH per year per kW of panels, quite pessimistic -- I'm in Arizona, and I'm getting 2 MWH / year / kW, and Olympia, the dreariest part of the country, gets more than half the sun-hours we do here. Now plug in the Wikipedia figures for annual US electricity consumption, divide by 50, and compare with budget figures.)



Comment Don't be a PV efficiency snob (Score 4, Informative) 129

Developments like this are awesome, because they open up the possibility of doing exactly what the summary describes -- using solar power to recharge things where size / weight / surface area is at a premium.

But those sorts of scenarios are few and far between. Most of the time, cost is the limiting factor, and these high-efficiency designs are always costly.

That's okay, though: PV panels are already plenty efficient for their desired function in most cases.

A typical location within the U.S. gets an annual average of 5 full-sun-equivalent hours per day. This means that the 1000 W/m solar flux reaching the ground when the sun is straight overhead is effectively available for 5 hours each day. Each square meter of panel is therefore exposed to 5 kWh of solar energy per day. At 15% efficiency, our square meter captures and delivers 0.75 kWh of energy to the house. A typical American home uses 30 kWh of electricity per day, so we’d need 40 square meters of panels. This works out to 430 square feet, or about one sixth the typical American house’s roof (the roof area of a two-car garage). What’s the problem?



Comment Re:Where are the FTL comms coming from? (Score 3, Interesting) 256

If you can do faster-than-light travel (or communication), then you can travel backwards in time. That's basic relativistic geometry.

And, if you can travel backwards in time (or communicate with the past), then you can construct a perpetual motion machine. Deplete a battery, recharge it, and send it back in time to before it was depleted. The past now has two batteries, both full, where it previously only had a single full battery. Lather, rinse, repeat. Even if you can only communicate with the past, you can play Maxwell's Daemon: analyze the motions of a random gas, figure out what you would have done to separate the gas into hot and cold sections, send the instructions back in time, and profit! Not to mention, of course, that communication itself requires an exchange of mass / energy...rather than send a message to the past, you could just use the carrier wave to send energy to the past. The past gets the power output from the fusion reactor you're using for your time machine, and it doesn't have to "burn" any of its own water to do so.

I won't state with perfect certainty that perpetual motion machines (and therefore time travel and faster-than-light travel) are impossible, but I will state that there is no other physical phenomenon we can be more confident doesn't exist than a perpetual motion machine (or, by extension, anything that requires a perpetual motion machine or can be used to construct one).

Oh -- and all magic, including all gods and all their miracles (at least, all those I've ever heard described), neatly fall into that latter category. It's the easiest way to separate science fiction from fantasy: do you get more (or less) out of that magic wand / warp drive / mind trick than you put into it? If yes, it's fantasy; if no, it's fiction.



Comment I just block (Score 4, Insightful) 716

I hate advertising in all forms, including that from vendors whom I might otherwise like. I'd much rather live in a world without advertising than one with one. So, for me, that's basically the world I live in.

No, I don't care that your revenue depends on advertising. I don't want your buggy whips, even if they're "free," even if you won't give me stuff for "free" unless I take a buggy whip. Find some other way to pay the bills.

And I don't think my attitude is at all outrageous or selfish. Would you accept "free" cake that came topped with "free" output from the sewage plant because that was the only way they could dispose of the waste? Would you feel guilty about decontaminating the cake before eating it? If you couldn't decontaminate the cake, would you still eat it anyway?



Comment Duh! (Score 4, Informative) 374

Considering our environment is changing at a radical pace, I'd think it obvious that we're still subject to evolutionary pressures. Now more than ever.

No, not just climate change -- that's going at a much slower pace than the change in diet, access to medical care, exercise habits, and the rest.

(What, you thought that a higher proportion of people with genetic diseases surviving to reproductive age somehow doesn't contribute to the change in allele frequency in the human gene pool?)


Comment Makes sense (Score 1) 402

Don't tell me it's not possible. What is possible for pedophiles should be possible for trainee terrorists and their supporters, too.

He's exactly right.

Which is why only production of pedophilia should be illegal, and why it should no more be censored than such terroristic revolutionary documents as the Declaration of Independence and the Federalist Papers. Or even Mein Kampf or the Bible.

Government repression of free expression, on the other that's something that should be considered treasonous.


Comment Solving the worng problem (Score 5, Insightful) 140

Sure, sonic booms are (more than just) annoying, but that's not why we're highly unlikely to ever see supersonic commercial flight again.

The problem is that supersonic flight requires too damned much fuel for too little gain. Airlines are struggling to make a profit with today's already-fast airliners as fuel costs skyrocket. Cutting a six-hour flight (with a hour of "secure" groping before takeoff and another hour each to get to and from the airport) to a four-hour flight (with the same groping and pre- and post-travel times) just isn't that big of a deal. And it's especially not worth more than double the expense.

Figure out a way to move just as many people at a time with existing infrastructure with half the fuel, even if it means adding 50% to the travel time, and then the airline industry might get excited.

But this thing just ain't gonna take off.



Comment Re:A solution in search of a problem (Score 2) 416

What you're missing is that the iPad weighs just over a pound and is the size of a couple dozen sheets of paper...and it can hold a ton of books.

No, literally.

Figure a pound per paper book (they're generally heavier, much heavier in the case of hardcovers) and 10 Mbytes per ebook (generally smaller, unless they're multimedia-rich), and 2,000 paper books would weigh a ton while 2,000 ebooks would use 20 Gbytes. iPads come in 16, 32, and 64 Gbyte models.

Tell me you don't get excited at the thought of carrying around a 5,000+ book library with you everywhere you go, and holding it all literally in the palm of your hand.

Oh -- and the iPad also blows the pants off consumer-level general computing devices of a decade ago, plus it's got a built-in video camera, GPS, and way more.

Now, you might not like Apple's business practices, and I certainly couldn't blame you for it. And an iPad is useless when the battery runs out, isn't the best of the lot in direct sunlight, and so on.

But there's just no way I can take seriously anybody who doesn't see the advantages an iPad (or a similar tablet from another manufacturer) has over dead trees. Or anybody who doesn't see the writing on the wall that dead tree books will, in a very short time, be preferred only by the nostalgic or those with very specific fringe-case use requirements.



Comment AdWords, not search! (Score 2) 315

I can't believe all y'all're missing the point so spectacularly.

Yes, searching on Google is free. So what? Over-the-air TV is free. That doesn't mean a broadcaster can't have a monopoly.

Google's not a searching company any more than they're a Webmail company or a YouTube company or whatever.

They're an advertising company. Their customers are those who pay them to run ads, and the product they sell to their customers is the eyeballs of those who see the ads.

And they are very much a monopoly in that arena.

Sheesh. It's like everybody else who's posting on this thread needs to turn in their Geek cards. I thought y'all knew this already...?



Comment Re:Public Transit (Score 3, Interesting) 938

Feel free to check all my figures.

$30,000 is reported multiple places as the average new car purchase price, and ten years is the typical lifetime of a car. That's $3,000 / year.

The average car loan is 70 months -- call it 6 years. A six-year $30,000 loan at 6% will cost you almost $6,000 in interest; that's $600 / year over the life of the car ($1000 / year during the loan, nothing after it's paid off).

10,000 miles / year @ 30 mpg @ $3 / gallon = $1,000 / year.

Insurance varies, but it's about $1,000 / year.

We're at $5,600 already and I haven't added in maintenance, registration, emissions testing -- or, for that matter, the cost of real estate to park the thing.

If anything, my $6,000 / car / year figure is probably conservative.

Yes, it's possible to spend less -- much less. I drive a '68 VW Camper that's been paid for since before I was old enough to drive and only put a few thousand miles on it per year. I doubt I spend $1,000 / year. But if we're going to consider el cheapo anomalies like you and me, we also need to consider all those driving around in BMWs that they trade out every year -- and the carless are equally offset by those with Lamborghinis. And those who only buy used vehicles are offset by those who only buy new ones.



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