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Comment Boat still hasn't left port (Score 5, Interesting) 239

Bitcoin made a lot of progress on the technological front, but its economics is flawed because it limits the number of bitcoins which can be mined, and makes them progressively harder to mine as more are found. This is the same flaw behind using gold as your currency standard, and will cause the same problem - economic instability via repeated bouts of deflation. Basically, because the amount of gold (bitcoins) doesn't grow as quickly as the size of the economy, prices for things in that currency start to go down.

Vastly simplifying the economy into one currency and one product, today there are x bitcoins and you make y widgets. The price for a widget is thus proportional to x/y. Tomorrow, the number of bitcoins hasn't increased as quickly as your economic activity is increasing. There are 1.2x bitcoins, but you make 1.5 widgets. The price for a widget becomes proportional to 1.2x/1.5y = 0.8x/y. In other words, deflation - a widget is only worth 80% what it was yesterday.

Now apply the same principle to all goods and services, and the price of everything is going down (actually the price of bitcoins is going up). Once people start to understand what's happening, they stop buying things. They want to wait until the last possible minute, until they absolutely need an item, to buy it because the longer they wait (the longer they hold onto their bitcoins), the less it will cost. This slowdown in economic activity causes a recession, which decreases the number of widgets that are made until once again their price goes up (because not enough are being made to meet demand), which starts the same process over again. Economic instability.

That's why every major economy has abandoned the gold standard for a fiat currency. Yes a fiat currency can be abused if the people in charge of it are corrupt. But used properly with the money meted out at about the rate the economy is growing, prices remain stable and so is the economy. Just look at the list of recessions in the U.S. pre-1933 and post-1933 when the U.S. went off the gold standard. The economy has been much more stable with a fiat currency. That's what needs to happen with a cryptocurrency for the "boat to leave port." If someone can come up with a cryptocurrency which is independent of central control, yet its supply increases at roughly the same rate the economy expands, that is the boat you want to get on. It just won't be as lucrative for early adopters as bitcoin because it won't be a ponzi scheme.

Comment It's an e-reader, not paper (Score 1) 145

The whole point of a LCD or e-ink display made of pixels is that you can display whatever you want. There's no requirement like paper where you have to pick a font and your'e stuck with it. Manufacturers need to let the device's owner load up and use whatever fonts they want. I mean sure the publisher and device manufacturer can recommend a font, but they have no business dictating what font is used on your device. Forcing you to use one particular font is like making a radio with a tuning knob, but only allowing you to listen to one station.

Comment Re:You Live In The Wrong Time Zone. (Score 1) 109

Changing time zones is only a temporary fix. My body's internal clock seems to be set for a 25 hour day. The early riser's internal clock seems to be set for a 23 hour day. I'm slow to get up but can work well into the night. They get up early, but crash sometimes before it's even dark outside.

Comment Re:Grace? (Score 1) 562

To get a ticket for going 34 mph in a 25 mph zone usually means you angered a cop,

Doesn't really work like that. You're assuming there are two variables - how fast you were going, and the speed limit.

There are actually three variables. How fast you're going, the speed limit, and how fast the cop says you were going. I was going about 45 mph in a 40 mph zone (used to be a 55 mph zone when I lived there a decade ago so I thought I was far under the limit). On the ticket, the cop wrote that I was going 55 mph just to get around that pesky 10 mph grace. Best I can tell, he was upset that I did a jackrabbit start from a red light, which I did to pass a slow car I'd been stuck behind (the road split into two lanes for a short span at the light). I'm a pretty safe driver and very aware of what I'm doing - that's my only ticket in over 30 years driving.

Comment Re:legalism is a crap philosophy. (Score 4, Informative) 562

All of this should make the UK a very dangerous place for pedestrians if speed limits alone were a primary driver of road fatalities, but they aren't. The UK averages 3.6 fatalities per billion kilometres driven. The US average (where limits are on average lower) is 7.1, which is effectively double. It seems much more likely that issues like car quality, driver certification, road design, car design etc are far more influential.

I don't disagree with your point, but you're conflating a bunch of numbers which aren't really comparable.

1) Motor vehicle fatality rate doesn't tell you much about pedestrian fatality rate.

2) Driving distances area greater n the U.S. so those billion kilometers driven are not comparable. Dividing the fatalities per 100,000 inhabitants by fatalities per billion km yields 8100 km/inhabitant per year in the UK, versus 14,900 km/inhabitant per year in the U.S. So the average American travels 84% further each year than the average UK citizen. Most likely, a greater percentage of those U.S. miles are at higher speeds on highways where accidents are more likely to be fatal.

The problem at speeds higher than about 50 mph is physics. Given how bodies strapped inside a car react in a crash, 50 mph is about the point where internal organs and blood vessels start tearing apart from their own momentum in a crash. At 100 mph, accidents are almost always fatal for the same reason (energy that goes into tearing up your internal organs is 4x more than at 50 mph). So a disproportionate number of traffic fatalities come from these higher speed accidents. In other words, a single stat like fatalities per billion passenger km doesn't give you the complete picture. You need to control for traffic speed distribution within those billion km first just determine if there's any blame left over to be assigned to other factors like car quality, driver certification, road design, car design, etc.

Comment Re:Physics puts enormous limits on using 30-300GHz (Score 1) 33

It's worth pointing out that the frequencies with problematic RF transmission (high attenuation) are precisely the ones the FCC likes to open up for unregulated use. Nobody wants to use those frequencies commercially or for safety because of their unreliability. And the high attenuation means any broadcasts which exceed the unregulated power cap (typically 1 Watt) only affect a small area. 2.4 GHz was opened up because of its high absorption by water molecules, which is why microwave ovens (2.45 GHz) completely screw up your wifi signal.

Comment Re:All for free!!!! (Score 4, Interesting) 150

For the rest of the 99.9999% of the flight this is dead weight that the plane has to burn fuel in order to carry it around.

If I remember right, if a stewardess loses a sugar packet in some crevice of an airliner, the extra weight (4 grams) will cause an additional half liter of fuel burn in a year.

It would probably make more sense to assign a tractor to drag each aircraft from the gate to the start of the runway rather than use the planes fuel to taxi around.

That actually brings up another problem with the idea. The point of moving around under your own power while on the ground is so that any immediate problem with the engines or fuel reveals itself during taxi when you are nice and safe on the ground. Not when you are 10,000 ft in the air hurtling at 400 mph.

I'll also add that the energy from combining hydrogen and oxygen to form 1 liter of water releases 237.14 kJ/mole (Gibbs free energy). 1 mole of water is about 18 grams, so 1 liter of water is formed for every 13.15 MJ released this way. An A320 has a maximum landing weight of 66 tons, so figure it's about 60 tons in regular service with a full load. Stopping from a landing speed of 135 knots, that's 252.5 MJ of kinetic energy. Enough to convert just 19 liters of water into hydrogen and oxygen at 100% efficiency. However, some of that kinetic energy is shed by the spoilers and thrust reversers, not the brakes. Frankly I'm not even sure that's worth the extra weight of machinery to recover.

Summing all this up, the maximum energy you can recover from braking an A320 at landing is equivalent to 5.5 kg of aviation fuel (46 MJ/kg). At a (realistic) 25% conversion efficiency for the fuel, and (optimistic) 60% conversion efficiency for the electrolysis and 70% efficiency for the hydrogen fuel cell (42% overall), this device will basically be reducing your fuel requirement by about 9.24 kg (11.5 liters). Every 8 grams the device weighs more than that will result in an extra liter of fuel burn per year than just carrying around the extra fuel.

Comment Re: What's the deal... (Score 4, Informative) 262

A pro competitor at Tour de France averages 450 watts. Casual fit rider averages 220. That means having a mere half a horse power would let the casual rider win the Tour de France

For those weak at the unit conversion, there's a nice rhyme for remembering it.

In fourteen-hundred and ninety-two,
Columbus sailed the ocean blue,
Divide the year of his voyage by two,
And you get the number of Watts in a horsepower.

Comment Re:Let's be fair (Score 1) 158

I bought one of these for my dad for Christmas. It's not going to win any benchmarks, and you'll feel it lagging on any processor-intensive tasks. But for office tasks, email, and web browsing it's fine. The biggest annoyances are a mini-HDMI port instead of a regular HDMI port - not that bad in itself, except Asus does not include an adapter. And the beautiful 13.3" 1080p screen is made blurry by Windows 10's (still) inadequate scaling in most apps.

Comment Re:Any VGA? (Score 1) 158

There are a lot more HDMI laptops out there than VGA projectors. So it's really the venues which still have VGA projectors who should have HDMI to VGA adapters on hand, than to expect every laptop owner out there to buy one or buy a VGA laptop, just in case.

The better venues use projectors configured to allow you to remote desktop/VNC into your laptop over the network (ethernet or wifi). So a lot of times you don't even need to be physically connected to the projector.

Comment Re:Article paid by Apple to boo over it. (Score 1) 455

Microsoft used to have 2-3rd place in North America at best, back before the iPhone and Android came out (#1 was BlackberryOS, #2 was PalmOS). Microsoft *could* have taken advantage of a decent position back then, but they, like Nokia, Palm, and BB, were blindsided by the advent of first the iPhone, then Android.

Microsoft used to be 1st. Back in the PDA days, PalmOS was 1st, Windows Mobile (or WinCE or a slew of other names they used for it) was 2nd. Microsoft gradually chipped away at it and eventually supplanted PalmOS as #1 for the simple reason that Palm wouldn't allow PalmOS on other hardware. Anyone else who wanted to make their own PDA had to invest in making their own OS (Nokia) or use Microsoft's offering. (This is the same mistake Apple made in the PC market, thus relegating them to a 5% market share today.)

Where Microsoft screwed up was the PDA and cell phone convergence. Everyone knew it was going to happen - two handheld electronic devices which you carry on your person all the time? Hell yeah they're going to converge. The only question was if PDAs were going to pick up cell phone capability, or if cell phones were going to gain PDA (organizer) features.

For whatever reason, Microsoft didn't see this and were content to sit on their laurels after having conquered the PDA market. HP (a major Windows Mobile vendor) tried to make a PDA which was also a phone, but without built-in OS support it was an exercise in futility and died in the market. Then Blackberry came out with a cell phone which also had PDA features and took over the market in almost one fell swoop. Palm responded quickly (but not quickly enough) and eventually died. Nokia, which had started off in phones, already had what was a combination phone + organizer, so did better than Palm and eventually owned the biggest market share when Blackberry failed to improve. Windows Mobile entered the cell phone game late and was relegated to a distant 3rd/4th.

There it remained as Blackberry and PalmOS were supplanted by iOS and Android. The former two were really just PDA features grafted onto a cell phone, while the latter two were generic OSes which basically make the smartphone a mini personal computer. In that respect Microsoft was already ahead of the game - Windows Mobile was also a generic OS for cell phones. But in an idiotic move, Microsoft insisted on tying it together with their desktop OS monopoly by forcing it to use the Win32 API and UI paradigm. (A Start button on a phone? Really?) Nobody wants to use the Windows desktop UI on a 4-inch screen. That allowed iOS and eventually Android to slip in and take over the market. By the time Microsoft got with the program, bought Nokia to try to salvage some market share, and came up with the excellent tiles interface for Windows Phone, it was too late.

IMHO that will go down in history as Ballmer's biggest blunder - missing the PDA and cell phone convergence. All Microsoft had to do was add cell phone support to Windows Mobile around the time Blackberry showed up, and allow Windows Mobile to grow as an OS for 4-inch screens instead of forcing it to be a mini-desktop Windows.

Comment Re:subsidies (Score 1) 298

Getting rid of all subsidies would have little to no impact on fossil fuel costs, while it would be devastating for renewables. Fossil fuel subsidies are large only because a huge amount of fossil fuels are burned compared to other sources. On a per kWh basis, the subsidy for renewables is 25x that for fossil fuels. The subsidy for solar is 1600x that for fossil fuels.

Comment Re:Plan B (Score 1) 298

If utilities don't do retail metering, consumers can get similar results by pooling their loads.

If you are using the electricity at the same place the solar panels are generating it, you are by definition unaffected by this decision. You are not selling the electricity back to the grid, you are using it before it even hits the grid, and thus you are unaffected by decisions which affect how much you get for selling electricity back to the grid.

If you are selling the electricity through the grid, then you should be getting the wholesale rate. Don't think of the power utility as one company, think of it as two - one which generates electricity, and one which distributes electricity.

  • The wholesale price is what the company which generates electricity gets paid to compensate for the cost to generate electricity.
  • The distribution company gets a distribution price, which pays for building and maintaining the power grid.
  • The retail price is wholesale + distribution (+ profit, but that's regulated in most states via a public utilities commission to a fixed percent).

If you generate your own electricity and sell it through the grid, someone still has to pay for distribution. The person who uses your electricity pays retail price. The distribution company subtracts their distribution fee. So you end up getting (retail price) - (distribution price). Which is the wholesale price. There's also the profit margin which needs to be resolved, but as I stated it's regulated in most states to a small fixed percent of the total so won't affect things much.

Expecting to get retail price for the electricity you generate is like a farmer expecting to get all the money a supermarket charges for his produce they sell. That leaves nothing to pay for transportation, distribution, and preservation costs for the food as it makes its way from the farmer to the final buyer. The only reason it ever happened with electricity is because the utilities weren't initially equipped to deal with it, and so as quick and dirty fix they just they made the meter run backwards if you were sending electricity back to the grid. Now that they have smart meters in place which can accurately tabulate electricity flowing in and out separately, it's possible to accurately pay you the wholesale rate.

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