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Comment Re:Economics? (Score 4, Insightful) 120

Nuclear power has a capacity factor of about 0.9. So a 1 GW plant will generate on average 900 MW throughout the year after taking into account downtime for maintenance and refueling.

8766 hours in a year (taking into account leap years), so that's 7889 GWh per year.

At a U.S. average rate of 12 cents/kWh = $120/MWh = $0.12 million/GWh, that's $947 million worth of power generated per year.

Nuclear plants are licensed to operate for 40 years. So that's $37.9 billion worth of power generated over 40 years.

Most of the older plants have had their license extended to 60 years. Some are requesting an extension to 80 years because everything is working just fine. So the actual power generated over the lifetime of the plant will likely be 1.5x to 2x higher.

So yeah, the $4.7 billion construction cost is tiny compared to the return you'll get. For your example of a 3.2 GW output plant that costs £24.5 billion ($30 billion) including financing, at the UK average rate of US$0.22/kWh, the expected power generated over 40 years would be worth $222 billion.

Comment Re:Guessing the real story here (Score 1) 85

The interesting thing is that they're implying the FBI was the source for these requests. The NSA and CIA have been able to weasel through their requests on the grounds that they're investigating electronic communications with people outside the U.S. who don't have Constitutional protection. i.e. Someone in California emails someone in Virginia, both are protected by the 4th Amendment, and there needs to be a warrant before their communications can be read by the government. But someone in China emails someone in California, and the NSA and CIA's legal argument is that the Chinese sender doesn't have 4th Amendment protection, so they are within their rights to intercept communications en masse without a warrant, then filter out entirely domestic communications which would require a warrant, leaving only international communications.

The FBI does not have jurisdiction outside of the U.S. (that's the CIA's and NSA's job). The only time they're allowed to investigate something outside the U.S. is when a foreign country invites them to do so (e.g. Pan Am bombing over Scotland). So if it was in fact the FBI which made the request, I'm curious what sort of legal argument they used to get this type of widescale monitoring approved by the FISA court.

Comment Re:Numbers (Score 1) 52

China's GDP is about 2/3rds that of the U.S. So yes it is a bit surprising that iOS app store revenue is greater for China than for the U.S. My guess would be the later introduction of the iPhone and iPad into China means people there are still in the "stocking up on apps they want" stage, while Americans left that phase 4-5 years ago.

Comment Re:So it appears . . . (Score 4, Interesting) 169

The burn cut off 19 seconds before loss of signal, so the probe was in freefall for at least 19 seconds. From TFA:

Not only is the chute jettisoned earlier than called for in the predicted timeline, but the retrorockets that were due to switch on immediately afterwards are seen to fire for just three or four seconds. They were expected to fire for a good 30 seconds.

In the downlinked telemetry, Schiaparelli then continues transmitting a radio signal for 19 seconds after the apparent thruster shutoff. The eventual loss of signal occurs 50 seconds before Schiaparelli was supposed to be on the surface.

That last sentence, if you assume loss of signal corresponds to impact with the ground, suggests de-orbit velocity relative to the ground was much higher than expected. The early parachute release may have been the culprit. Or the probe entered the atmosphere at too steep an angle (which could also explain the early parachute release - the probe would've entered higher density atmosphere more quickly thus increasing aerodynamic load on the chute to the point at which it failed). The burn probably began at a higher velocity than it was designed for.

If we're speculating, my guess would be the higher velocity when the retro-rockets were fired caused greater instability - aerodynamic forces caused the probe to rock more than expected. The parachute's purpose isn't just to slow the craft down; it also keeps the craft's orientation stable during this period of higher aerodynamic forces. Without it, drag on tiny asymmetries on the front of the craft can result in large turning moments. With a parachute attached, these moments are countered by the righting moment the parachute imparts on the rear of the craft every time it deviates from the proper orientation. Without the parachute, the craft can experience large oscillations or even flip due to these drag-induced turning moments. The large amplitude and higher frequency of the resulting oscillations could've exceeded what the rocket control software was designed to handle, and it shut off prematurely when it exceeded some threshold programmed into the software.

Comment Re:MagSafe have save me tons of money (Score 1) 300

My sample size is small, but I've had friends/clients come to me with 2 flaky Macbook AC adapters (with magsafe cords), vs 3 failed PC AC adapters and 1 failed laptop power socket.

If you factor in that PC laptop sales are approx 9x Mac laptop sales, the magsafe AC adapters have a 4.5x higher failure rate than the PC AC adapters.

Also, realize that magnetic power cords were used on deep oil fryers (where the cord trip hazard is much more serious) for decades before Apple used it on laptops. The only reason it's not used on PC laptops is because nobody wants to spend the millions it would cost to challenge a patent that was incorrectly granted to Apple for a pre-existing invention.

Comment Why is anyone making a 4GB device in 2016? (Score 1) 82

Here are the spot prices for MLC NAND flash memory. There's been a (probably temporary) spike in the last month, but the long-term average price has been:
less than $10 for 64GB
less than $5 for 32GB
$2.50 for 16GB
about $2 for 8GB
about $1.80 for 4GB.

Why in the world would anybody make a 4GB device in 2016? Bumping up to 16GB only costs about 70 cents more per device. I tried to buy a 2-4 GB microSD card for my Roku because people said it didn't need any more, but there weren't many available anymore and the price difference was so negligible it was easier to just get a 16GB card.

Comment Re:A quote comes to mind (Score 1) 46

An old boss of mine said "If you had time to do it a second time, you had enough time to do it right the first time".

That shows a gross ignorance of the probability tradeoff involved here. Just because recall expenses for one product exceeded the marginal design cost to "get it right the first time" doesn't mean that's the most cost-effective way to design everything. The ideal production point isn't to design and manufacture everything so you never have to do a recall. It's to build stuff so that most of the time you won't need a recall. And the few times you do need to recall a poor design, the cost of that recall is cheaper than having to overdesign everything. If you issue n products and

  • overdesigning each cost $x
  • designing them with a slimmer safety margin would only cost $(x-y)
  • with the slimmer margin you average 1 recall per n products at a cost of $z

Then "doing it right the first time" has a cost of n*$x, while living with the slimmer margin results in a cost n*$(x-y) + $z = n*$x - n*$y + $z.

So as long as n*$y (the total amount of money saved by designing all products to a slimmer safety margin) exceeds $z (the cost of the single recall), then suffering the occasional recall is the more efficient economic strategy. I know everyone would prefer having all their toys be perfect, but that perfection would come at the cost of you being able to afford fewer toys. You are actually able to afford more toys which work as if they were perfect if you're willing to accept that a few toys won't be perfect, than if you demand all your toys be perfect.

The tradeoff gets muddled when lives are at stake, since it's difficult to place a value on a human life. (Well, placing an economic value on one is easy. Social, emotional, and moral value is difficult.) But we're talking about a smartphone. A modern convenience which didn't even exist 20 years ago.

Also, the manufacturers aren't who you need to convince here. The people you need to convince to change are the idiot reviewers in the media who pan any phone which doesn't match their misguided preconception of what a "good" phone is, and the people who buy based on those reviews. Everyone here complains phones are too thin, and most of the people I know just end up putting a case on the phone to make easier to hold. Bendgate disproved the notion that metal was better, with quantitative measurements showing that the plastic phones were equal to or stronger than the metal phones at resisting bending. And most reviewers don't use a review phone long enough to run down the battery multiple times under real-world use conditions (loaded with lots of background apps sucking power throughout the day), so tend to undervalue the importance of long battery life. The manufacturers just build to the unrealistic market expectations created by ignorant and misguided reviewers.

Comment Re:I hope Apple Pay will die (Score 1) 283

It saves the banks money because it drastically reduces the fraud rate. So, no consumers are not paying for this

Banks and credit card companies do not pay for fraud. They've set it up so the merchants pay for fraud. If you spot a fraudulent transaction on your card, request a chargeback, and the bank approves it, the merchant is out the money and the merchandise - they've paid for the fraud. The fees the banks and credit card companies collect pay for transaction costs, and for people who default on paying back their credit card debt.

Also, it's disingenuous to claim the merchant or customer does not pay for these fees. The credit card companies got laws passed making it illegal for merchants to charge an extra fee for credit card transactions. Consequently when you buy something with a credit card, it's the same price as if you paid in cash (a rare exception being stores which use the "cash discount" loophole). So the fee is coming straight out of the merchant's markup on the item sold - the merchant is paying for the fee. If you want to kick it up one more level, the merchant has to raise its prices to compensate for this reduced effective price markup. So the fee is coming out of the customer's wallet, with cash customers subsidizing the fee for credit card customers since their transactions do not incur the fee, yet they still pay the higher price.

Comment Helps prevent spoofing (Score 2) 146

The U.S. government screwed this up royally when it put its site for people to get their free credit report on the domain annualcreditreport.com. The credit agencies all set up similar sites with similar domains, which would give you your credit report but require you to submit a credit card and would try to subscribe you to their credit monitoring services. For years, Google searches would return these spoofing sites instead of the real one as the top result, doubtless due to aggressive SEO. It seems to have stabilized on the real one as the top result now, though I don't know if that's due to Google clamping down on SEO exploits, or if they just hard-coded the government site as the top result. All of this could have been prevented if the government set it up as a .gov TLD, since companies can't set up sites under that domain.

Likewise, a .apple, .ibm, .canon, .samsung TLD would prevent spoofed sites. I tend to side with a strong hierarchical structure to domain names (company.com, organization.org, network.net, etc). But not everyone realized the importance of nabbing a .com domain early on, resulting in headaches which have done nothing but make lawyers rich. Granting an organizations-specific TLD if the organization is large enough may be a solution to this, provided you also prohibit said organization from taking over similarly named .com sites like applesucks.com. Once you own a TLD that only you can make sites on, it's clear whether or not a site is your "real" site, so name confusion and trademark dilution claims should no longer apply.

Comment CO2 didn't cause Venus' hellish conditions (Score 3, Interesting) 123

Although that's certainly how some people will try to spin it. Venus' atmosphere is theorized to have begun much like Earth's. The crucial difference was its proximity to the sun caused its water to mostly turn into vapor, instead of remain as a liquid. This (1) contributed to the greenhouse effect - water vapor is the biggest greenhouse gas contributor on Earth despite only a tiny fraction of our water being in vapor form, and (2) rose above heavier CO2 thus shielding it from being lost into space or being broken apart into its elements by solar radiation (Venus has almost no magnetosphere to protect it).

So Venus' CO2 was allowed to build up instead of being lost to space, eventually leading to the enormous pressures Venus has today. Mars's atmosphere has a similar composition (both are 96% CO2), but due to its weaker gravity and lack of water vapor, most of Mars' CO2 was lost into space giving Mars a surface atmospheric pressure only 0.6% that of Earth's. Venus' surface pressure by contrast is 92 times Earth's atmospheric pressure at sea level. CO2's critical point is at 73.9 bar (atmospheres) and 31 C, above which the difference between the gas and liquid phases disappears. So the CO2 "atmosphere" on Venus' surface is more like a sea of CO2 fluid (the Venera landers didn't even use parachutes for the final descent - they gently floated down using nothing but hull drag). You basically have the greenhouse effect of the CO2 gas, compressed into the higher density of liquid CO2. All made possible by excess water vapor early in Venus' early history.

Earth's early atmosphere was also nearly the same as on Mars and Venus. But Earth retained liquid water, which was able to dissolve most of the CO2, creating the "habitable" conditions for life we have today. So it's actually liquid vs gaseous water which is the key difference, not CO2 levels. In fact Venus' present atmosphere is theorized to actually be much more hospitable. In the past when water vapor was still present, temperatures there were probably twice what they are today.

Comment Re:Resiliency in the face of malicious inputs (Score 1) 365

I don't see why there has to be a single answer to this. There are already laws in place governing traffic flow. Violators of those laws (people running red lights, jaywalkers, etc) should be given lower priority in the "attempt to save" ranking.
  • If the vehicle calculates it has to leave the road to avoid an accident, but its trajectory would make it hit pedestrians on the sidewalk, protect the pedestrians and do not avoid the accident. Basically, accident avoidance in this case requires the vehicle to leave its legal lane of travel, so the pedestrians traveling legally on the sidewalk should get higher priority.
  • If the vehicle is traveling legally on the road and a pedestrian jumps/falls into the vehicle's path, swerve to avoid the pedestrian if possible, but go ahead and hit the pedestrian if swerving would result in hitting another car. I'm thinking of an accident near my workplace where a driver swerved to avoid a cat that ran into the road, hit another car, flipped, and killed himself. He basically gave his live to save a cat (which lived). Multiple accidents of this nature in the same location are an indication that the speed limit is too high, or that the road needs some sort of protective barricade (e.g. prevent kids from the nearby playground from chasing balls out into the street).
  • If both vehicle and pedestrian are traveling legally when the collision occurs, then obviously this is an oversight (a "bug") in the vehicle code. The law needs to be changed, and neither the car nor pedestrian should be liable for the consequences of the accident. The car should be free to respond as it wishes in this case, although there are two major factors which favor protecting the pedestrian:
    • The occupants of the vehicle are strapped into and enclosed in a crash-rated metal safety cage, and can survive much higher accident forces than a pedestrian.
    • The vast majority of the energy of a crash is coming from the car, not the pedestrian. So in the event that an accident is unavoidable, it is just Right that most of that energy be directed at the car's occupants, not the pedestrian. If you feel the need to hurtle yourself at death-defying speeds (pretty much anything over 45 mph) to get somewhere faster, then you should bear the consequences of your choice. Not be allowed to inflict those consequences upon someone taking a casual stroll down the sidewalk.

Comment 2 years seems rather excessive (Score 2) 87

2 years to build a new Soyuz capsule after it's ordered? It takes Boeing and Airbus about 80 days to build a 777 or A380.

Even factoring in number of orders doesn't account for the difference. There are about 15 Soyuz launches per year. Airbus is delivering about 30 A380s per year. So that would only account for a factor of 2, putting expected build time for a Soyuz at 160 days, or less than half a year.

Comment Weird metric (Score 1) 44

That's a really weird metric to use. Since these services charge per month (or per year for Amazon), isn't the relevant metric individual users per month, not individual users per day? In fact, like MMOs, doesn't a service like this want its users per month metric to be high (to maximize revenue) while keeping its users per day metric low (to reduce bandwidth costs)? Though of course GB per user per month would be a more accurate assessment of bandwidth than users per day.

Even advertisers would be more interested in hours viewed per day, or hours viewed per user per day. I can't think of any way users per day is a useful stat. Maybe to someone maintaining the login servers so they know on average how many authentication requests they'll have to handle per day?

Comment FWIW, Android lets you block notifications per app (Score 1) 25

Feature was introduced in Marshmallow I believe. I had to do that when a utility app which had previously been silent got updated to spam me with ads disguised as a notification popup every few hours.

Settings -> Apps -> [app in question] -> Notifications -> Block all

You can also control most app permissions (independent of the app requesting them) in the same place.

Settings -> Apps -> [app in question] -> Permissions

Doesn't let you control an app's network usage (except cellular data use in the background). But if you're rooted you can use AFWall+ to do that.

Comment Re:This doesn't prove what they were hoping to pro (Score 1) 192

""Eighty-four percent of clinicians listed the correct diagnosis in the top three possibilities, compared with 51 percent for the digital symptom-checkers."

I'm surprised that digital diagnosis is that good already.

When comparing percentages, you need to compare them in the manner which has the biggest consequences. A good example is OCR software (optical character recognition). If one has an accuracy of 99.99% and another cheaper one has an accuracy of 99.95%, you might think there's very little difference between the two and you should buy the cheaper one. But the cheaper one has a 5x the failure rate (.05% vs .01%), meaning you'll have to spend 5x as much time fixing errors in the scanned text.

Likewise, a 84% vs 51% success rate is not a mere 33% difference. It's a 3x higher failure rate (16% vs 49%).

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