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Comment Re: I am not a physicist but... (Score 1) 281

I wouldn't be so sure. Japan was the first country to travel that route. In the 1950s Japanese products were considered garbage. By the 1980s, it was considered some of the best stuff in the world. But it's GDP per capita (nominal) has stagnated around $35k/yr vs about $55k/yr for the U.S. and $45k/yr for most of the Western Europe.

South Korea and Taiwan are the two more recent countries to advance that way (products considered to be cheap trash in the 1970s, desirable by the 1990s). But their GDP has stagnated at around $25k/yr per capita. (Yes Taiwan - nearly all laptops are designed in Taiwan). Singapore would seem to be an exception at about $55k/yr, but it's a city-state and achieves that high GDP by not having any low-income rural residents.

There is just something about these East Asian countries which is preventing them from reaching the level of productivity that the U.S. and Western Europe have reached. My theory is it's corruption (bribery is a fact of life there) and ingrained rules of society which impede free market forces from helping remove inefficiencies. If I'm right, then China, currently at about $8k/yr, is probably going to stagnate before it reaches $15k/yr due to its Communist government trying to micro-manage everything its people do. That would be enough to supplant the U.S. as world's largest economy, but it will hardly be world-leading when it comes to technologies. I mean it will have a few world-leading breakthroughs due to the sheer size of its economy and population, but the amount of technological advancements per $GDP and per citizen will be far below what we see from the U.S., Western Europe, Japan, South Korea, and Taiwan. You could even argue China has already reached its peak - $8k/yr GDP per capita is where Russia stopped at when it was the Soviet Union (inflation adjusted), and where it is right now.

Technological progress doesn't just come from dumping money into R&D. You also have to give your researchers and engineers freedom to try out all the crazy ideas they can think of. And have a free market which can sort out the good ideas from the bad (instead of some government official designating that one idea is good while another is bad).

Comment Re:Price Is Still Just One of Two Sticking Points (Score 2, Informative) 170

Oh, while we are at it, SSD tend to fail spectacularly: i.e. usually when they perish you cannot extract any information at all vs. spinning platters which usually fail gradually.

Most newer SSDs are designed to fail gracefully. When they die, they become a read-only device. All your data is still accessible. Many USB flash drives are designed to fail the same way - if you've ever had a USB flash drive mysteriously become "write-protected", it probably died and set itself to read-only mode. Unfortunately, Samsung seems to be one of the SSD manufacturers which hasn't yet adopted this philosophy for failure. But I can understand their reasoning because...

P.S. If you wanna counter my first argument, fill your SSD up to 99% and then try to work with it continuously for quite some time. That 1% will get overwritten multiple times and your whole SSD will be prone to a failure.

That problem was solved in the 2000s with wear-leveling algorithms. Basically, the "sectors" the SSD presents to the computer aren't actual physical locations. They're virtual locations stored in a table. If the SSD senses certain blocks being used too much or other blocks sitting unused, it moves the data around behind the scenes so that writes hit all flash memory cells about equally. It updates the virtual table every time it does this, to fool the computer into thinking the drive is physically the same as it has always been.

The rated endurance on most consumer SSDs is around 2000-3000 cycles. For a 250 GB SSD, that means you can write 625 terabytes to it before expecting a failure. If you write 100 GB of data to the drive every day, you can expect it to last nearly 20 years. In torture tests, most SSDs have lasted about 2-3x longer than their rating. And no, the first cell failure is not catastrophic. Pretty much all SSDs have a number of reserve cells sitting on the sidelines to take over for cells which fail early.

If your duty cycle is higher than 100 GB/day, they make special enterprise SSDs rated for 10k-100k writes per cell. The price is correspondingly higher of course, primarily due to using SLC (one bit stored per cell) instead of MLC (2 bits) or TLC (3 bits).

Limited number of writes were more of a problem in the early days of SSDs when they were like 32 GB in size. In that case, the exact same characteristics as the above 250 GB SSD would yield only 2.2 years of longevity. But the problem has pretty much become a non-factor as capacities have increased.

Comment Re:so what? (Score 1) 273

What about the US' ability to attack everyone? How about those pricks disarm and reduce their military to 1/10th the size, stop toppling governments because they don't like them etc?

You're mixing up capability with likelihood. Total risk is the product of the two. The U.S. has had nuclear-capable ICBMs for over 50 years now, but has never used them. So while it has had the capability for a long time, the proven likelihood that it'll use them is very low, even when it's been provoked. The reason people (not just the U.S.) is concerned about North Korea's capability is because its leadership is extremely erratic and unpredictable, so the likelihood it would actually use ICBMs is a lot higher than existing nuclear powers'.

Also, U.S. military spending is huge only if you look at it in raw dollars. That's like looking at the raw dollars a large wealthy household spends on food, and comparing it to what a homeless individual spends. If you insist on looking at it in raw dollars, we could divide U.S. military spending across all 50 states (many of them are larger than most countries) and *poof* - the individual states no longer have the world's largest military spending.

The proper normalized metric is spending (any type, not just military) as a percent of GDP. That eliminates the effect of wealth and population. Basically, what percentage of your citizens' productivity do you direct to your military? By that measure, U.S. military spending is about 3.5% of its GDP. That's only about 1.5x the world average of ~2.3% of GDP. By that measure, the U.S. doesn't even make the top 25 in military spending. And that's not even factoring in Japan, which the U.S. is contractually obligated to defend by the terms of peace treaties signed ending WWII. Include Japan's GDP and U.S. military spending drops to about 2.7% of aggregate GDP. If you cut U.S. military spending to 1/10th what it is now, it would have just about the lowest military spending of any nation on earth.

Incidentally, guess which country spends the most on its military as a percentage of GDP.

Comment Boat still hasn't left port (Score 5, Interesting) 266

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) 147

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) 110

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) 579

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) 579

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.

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