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Comment: Re:The internet-of-things is here to stay. (Score 1) 73 73

The internet-of-things is here to stay.

To the contrary, in my experience most things that have a catchy name before they are implemented go nowhere. Multicasting, Named Data Networking, Internet of Things, OLP, Web Ontology, Neural Networks, etc. The project is more focused in sounding trending than in finding reasons why things want to access the internet (presumably so that your toaster can watch youtube videos while you are away?)

Successful projects usually start from the other end. People first create a small iteration of the thing that proves the concept, it starts to catch up (fancy name might be created here but this is entirely optional) and one day you turn around and its taken over the world.

On the other hand, if IoT does take off, then about 3 to 5 years after that I'm going to start a new company and sell products with the exciting label of "Not Internet Connected!", and I'll make billions.

Comment: Re:Drone It (Score 1) 711 711

It - like the military itself - is kind of a Federal jobs program. If you keep your existing jets and don't build new ones, then you lose the employees with the skills and experience needed to do the job. (Kind of like we may not be able to build new nuclear weapons if we wanted them because we haven't made them for so long and everyone with any experience has retired.)

I find it interesting that we have to have the latest and greatest fighters out there, while our AWACS are 50 years old and our bombers are 60 years old. Neither system has been replaced, at least not with anything that lasted more than two decades and then got replaced or shelved.
Heck, the F-16 itself is still in use 40 years later having seen newer fighters come and go. Apparently, the F-16 can hold it's own against an F-35. Imagine what 3 1/2 of them could do against one F-35.

Comment: He's totally wrong. (Score 1) 277 277

When Bill Gates says:

"There's no battery technology that's even close to allowing us to take all of our energy from renewables and be able to use battery storage in order to deal not only with the 24-hour cycle but also with long periods of time where it's cloudy and you don't have sun or you don't have wind."

he's totally wrong.

For starters, there's Vanadium Redox. A flow battery (pumped electrolyte): Power limited by the size of the reaction device's electrode and membrane assembly. Energy storage limited by the size of the tanks. It's mainly used for utility-level energy storage down under (Oz or Nz, I think), because the patents are still fresh and the little startup doesn't want to license it to others. Vanadium is some substantial percentage of the Earth's crust so there's no shortage. Using the same element (in different sets of oxidation states - vanadium has (at least) 6 of 'em) for BOTH electrodes means leakage of small amounts of the element through the dilectric membrane doesn't poison the battery.

Lithum cells are already good enough to run laptops, cars, and houses, and are improving at a Moore's Law like rate. The elements are also not rare and the use of several nanotech techniques on the electrodes have drastically increased the lifetime and other useful properties. (We just had reports of yet another breakthrough within the last day or so, doubling the capacity and extending the life.) The fast-charge/discharge cells are also extremely efficient. (They have to be, because every horsepower is 3/4 kW, so even a few percent of loss would translate to enormous heat in an automotive application.) The main problem is to get companies to "pull the trigger" on deploying them - and risk their new production line being rendered obsolete before the product hits the market by NEXT month's breakthroughs.

Lead-acids need to be replaced once or twice per decade. But they have been the workhorses for off-grid since Edison's and Nikola Tesla's days, and still are today (though not for long, if Elon Musk and the five billion dollars of investments in his lithium battery plant have anything to say about it).

Nickel-Iron wet cells are a technology developed by Edison. They have more loss than lead-acids. But they literally last for centuries. If you have a moderately steady renewable source (like some combination of enough wind and a big enough windmill, enough sun and a big enough solar array, or a stream and a big enough hydro system) you'll have enough more power than you need to keep them topped off. They're just fine for covering days, or even a couple weeks, of bad generation weather, or down-for-maintenance situations. That IS what they were in at least one hydro plant I know of. (The problem is finding them: They last so long you only need to buy them ONCE, so there aren't many plants.)

That's just four FAMILIES of entirely adequate solutions. There ARE more.

So Bill is either uninformed, talking through his hat, or starting on the "embrace" stage of yet another:
  - Embrace
  - Extend
  - Extinguish

Comment: Re:If we're stuck with polls, how 'bout tech polls (Score 1) 131 131

I live in a subdivision with relatively spacious yards, but the fireworks are illegal around here. In fact, they are illegal even in the smaller towns. The only place they aren't illegal is in unincorporated areas which can be found here and there, usually with several large fireworks stands on them. Unfortunately, it is also illegal to transport fireworks through town, so you can't take them from the unincorporated place you bought them to the unincorporated place you live in. Police can and sometimes do just watch people buy them from the booth and then pull them over as soon as they cross the line into town.
Some of the fireworks stands have huge fields behind them so you can light them off there, but they are not open at night, so you don't get the full effect, and they are definitely not open at night on July 4th.
Effectively, you just can't legally fire off fireworks here on the 4th of July night. You had to have done something illegal, unless you happen to live in the same unincorporated area as the fireworks stands. In general, nobody lives in the unincorporated areas around here. They are just trees and fireworks stands.

Comment: Re:New Hampshire (Score 1) 131 131

It's your civic duty as a citizen of New Hampshire to purchase and light my own fireworks which were made in China, hence removing cash value from your own country and send it to China.

Well, since fireworks came from China in the first place, it's not like it is a big loss. Not like IT jobs, cars, electronics, etc.

Comment: Re:I'm not American so why would I care? (Score 1) 131 131

woooooh murkins coz thats the whole world and the entire slashdot audience

oh and the entire independence thing is an illegal act any way

It was an illegal act at the time. However, after lots of people died, the U.K. accepted and legitimized the independence of the United States.

Comment: Second law of thermodynamics. (Score 2) 277 277

we have a way to turn electricity directly into heat. But there is no direct way to turn heat into electricity. It has to go thru a second step of mechanical energy to spin a magnet to create electricity.

You can go from electricity directly to heat because that increases entropy. You can't go from heat to anything useful because that decreases entropy, and entropy of a closed system only increases. The best you can do is a heat engine, working off a temperature DIFFERENCE. (Some of them also work backward as heat pumps, to go from electricity to heat more effectively, by also grabbing some heat from elsewhere to include in the hot end output.)

There ARE at least two major forms of electronic heat engines - direct from temperature differences to electricity, with only charge carriers as the moving parts: Thermoelectrics (thermocouples, peltier junctions, and thermopiles of them) and thermionics (both heat-driven vacuum diode generators and a FET-like semiconductor analog of them). Both are discussed in other responses to the parent post.

Comment: Thermionics (Score 3, Interesting) 277 277

TEs are ridiculously inefficient and aren't looking to be much better anytime soon

Because thermoelectric effect devices leak heat big time.

However there's also thermionics. The vacuum-tube version is currently inefficient - about as inefficient as slightly behind-the-curve solar cells - due to space charge accumulation discouraging current, but I've seen reports of a semiconductor close analog of it (as an FET is a semiconductor close analog of a vacuum triode) that IS efficient, encouraging the space charge to propagate through the drift region by doping tricks (that I don't recall offhand). The semiconductor version beats the problems that plague thermoelectrics because the only charge carriers crossing the temperature gradient are the ones doing so in an efficient manner, so the bulk of the thermal leakage is mechanical rather than electrical, and the drift region can be long enough to keep that fraction down.

Comment: Re:GOOD. (Score 1) 226 226

I thought our national health insurance system was supposed to have solved all problems of this nature by now.

Why the fuck, in 2015, are Americans still relying on private insurance companies for health care? So much sigh.

Because insurance is not healthcare. All Obamacare did is require everybody to pay money to the insurance company. It didn't do anythign at all about healthcare. If anything, healthcare will suffer because now people who previously could at least afford to go to the doctor now have to pay for insurance instead and can't also afford to go to the doctor.

Comment: Re:Next time you complain about "lobbyists"... (Score 1) 226 226

... just remember: sometimes you need lobbyists to protect yourself from government.

This is an example of it: a social app's userbase is trying to protect themselves from the rent-seeking taxi cartels.

They have more lobbyists than Wal-Mart because Wal-Mart obeys the law. Uber is operating illegally and so they must use lobbyists to try to get the laws changed so that Uber will be legal.
They are trying to protect themselves from the government, but only because they started out being on the wrong side of the law. I don't see any social justice here.
Why refer to taxi companies as cartels? It wasn't their idea to institute medallions. It was the governments, due to overpopulation of taxis. The only thing that the taxi companies are trying to protect is that they had to pay cash up front and operate within the law in order to provide services, but Uber is getting away with operating illegally and not paying for the proper authority needed for them to operate.

Comment: Helping out google's algorithm (Score 2, Funny) 70 70

Here is a helpful hint for google's algorithm to determine if the click was accidental:
If I clicked it, it was accidental.
If I did not click it, that was intentional.
The only time I ever click on an ad is when I got suckered in by a deceitful company trying to appear to be a legitimate news article. For example, I got suckered in by "New Law has Insurance Customers Fuming" headline...once. A company that has to fool people into clicking on it's links does not deserve to be in business and should have their IP blacklisted so that no one else will ever accidentally visit their site.

Comment: Then again. (Score 1) 62 62

I got the impression from the (sketchy) article that repeater AMPLIFIERS were still needed but repeater REGENERATORS were not.

Then again - another part of the article makes it look like an additional result was that they could boost this less-subject-to-degradation-by-nonlinear-distortions signal at the start until the fibre itself was acting non-linearly, in order to get a signal strong enough to survive a much longer hop.

So it's not clear to me whether the distance was achieved by:
  - long hops enabled by strong signals, and NO amplifiers
  - longer propagation without regenaration using JUST amplifers
  - a combination of the two: Both getting long total length without regeneration AND being able to use stronger signals and thus use larger space between the amplifier-type repeaters.

Comment: but not amplifiers (Score 1) 62 62

Since the diameter of the earth is 7 926.3352 miles, this could conceivably remove any need for repeaters.

I got the impression from the (sketchy) article that repeater AMPLIFIERS were still needed but repeater REGENERATORS were not.

I.e. you still needed to boost the strength of the signal to make up for the losses. But the progressive degradation of the quality of the signal - with data from different frequency bands bleeding into other bands (especially in the amplifiers themselves) due to nonlinear "mixing" processes - had been headed off, by synchronizing the frequencies of all the carriers to exact multiples of a common basic difference-between-the-carriers frequency.

This apparently sets up a situation where the distortion products of each carrier's interaction with nonlinear processes cancel out with respect to trying to recover the signals on another carrier - much the way the modulation products do in OFDM modulation schemes. In OFDM it allows you to make essentially total use of the bandwidth. In this system it lets you use simple, cheap, amplifiers to get your signal boost, rather than ending the fibre before things get too intertwingled, demodulating all the signals back to data streams and recovered clocking, then generating a fresh set of modulated light streams for the next hop - MUCH more expensive and power hungry.

Comment: Re:Uber != car sharing (Score 2) 177 177

Taxi companies don't want to compete with Uber though, they just want to outlaw them and go back to their monopoly.

They don't want or need to outlaw Uber. Uber is already illegal. All the taxis want is for the competition to have obey the same laws, which legally they do. In practice, Uber chooses not to obey the law.

"There is hopeful symbolism in the fact that flags do not wave in a vacuum." --Arthur C. Clarke