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Comment Boat still hasn't left port (Score 1) 57

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) 140

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: OT Re:legalism is a crap philosophy. (Score 1) 558

It's not just stopping distance. Energy = mass * velocity squared, so getting hit at 35MPH is twice as energetic as getting hit at 25MPH.

Personally, I don't understand why anyone would speed on a residential street unless they haven't thought about it at all. Car doors can open at any time, people can be backing out of their driveway, and of course, kids and pets can run out into the street at any time. I just sort of assume it's going to happen and give every blind spot a wide berth and/or slow down a bit more than 25MPH.

I am the second fastest vehicle you will see on the highway (because the other guy can have that prize in the form of a ticket) but there are just too many potential hazards on a residential street. Even if you, dear reader, believe that a kid deserves to get hit, by you, for running into the street in front of his house just as much as if he ran into a freeway, an accident still takes up hours of time to resolve, and potentially years in jail for killing a pedestrian, if that happens, and you happened to have been speeding. At best, you're spending lots of money for a good lawyer, and many days at criminal trial, not to mention the wrongful death civil trial that's sure to follow. It's just a shitty risk/reward ratio, in purely selfish terms. Make up that time on the freeway, or by making sure you're not staring at your phone the next time the light turns green, or by learning to merge properly so as not to cause traffic jams.

God, I can't wait for autonomous vehicles to be mandated.

Comment Re:Grace? (Score 1) 558

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) 558

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 If you can't spend them... (Score 1) 158

How does EU legislation have any effect on Bitcoin? Just ignore them, same as those who legislate the value of PI.

If you can't spend any BT in EU because BT are not traceable as legally required, what do you think is then the usefulness of BT for merchant ? Zero. For all practical purpose this would make for the crushing majority of people BT worthless in EU, barring doing illegal transactions.

Comment this si the flaw of the US process (Score 1) 634

"Well, d'oh. If you change the electoral process you can get different results"
 
Then your electoral process is deeply flawed. With a direct process like in my country, it does not matter how many time you partition and recount : sum are commutative and associative in the end you get the same final number. But with a represenative process you have shenanigan like gerrymandering and you can "win" election before the vote and recount can change the results. That alone should tell you haw deeply flawed the process is.

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 nice looking graphs != useful graphs (Score 3, Informative) 59

They were glorified scan graphs some other company presented before which I can't recall the name. They used to have a software to which you could feed your firewalls logs and get a similar graphs (reverse lookup on country always showed my home IP as being from half a world away but i digress). The problem is that scanning does not mean threat or attacks, and those graphs means next to nothing beyond marketing. Sure nice looking. But empty of meaning.

Comment Boneheaded and with straightforward solutions (Score 1) 698

This is so boneheaded it beggars belief. The straightforward solution is to require the UEFI variable filesystem (or whatever it is called these days) to be mounted read-only, and require (UNIX anyway, but something analogous ought to work for Windows too) an application to do a "mount -o remount,rw" to do whatever it needs to do, then do a "mount -o remount,ro" when it's finished. Not as nice as having UEFI not be seriously broken, but workable, and there's not much of an excuse for things like systemd, openrc, etc. implementing this where appropriate (and for any UEFI crap that can brick a system, this is appropriate).

Applications don't like it? Tough, patch the damn things. Requireing firmware to be exposed to harm like this on any operating system is unacceptable.

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.

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